WorldWideScience

Sample records for water structural arrest

  1. Structural arrest in an ideal gas.

    Science.gov (United States)

    van Ketel, Willem; Das, Chinmay; Frenkel, Daan

    2005-04-08

    We report a molecular dynamics study of a simple model system that has the static properties of an ideal gas, yet exhibits nontrivial "glassy" dynamics behavior at high densities. The constituent molecules of this system are constructs of three infinitely thin hard rods of length L, rigidly joined at their midpoints. The crosses have random but fixed orientation. The static properties of this system are those of an ideal gas, and its collision frequency can be computed analytically. For number densities NL(3)/V>1, the single-particle diffusivity goes to zero. As the system is completely structureless, standard mode-coupling theory cannot describe the observed structural arrest. Nevertheless, the system exhibits many dynamical features that appear to be mode-coupling-like. All high-density incoherent intermediate scattering functions collapse onto master curves that depend only on the wave vector.

  2. The relevance of crack arrest phenomena for pressure vessel structural integrity assessment

    International Nuclear Information System (INIS)

    Connors, D.C.; Dowling, A.R.; Flewitt, P.E.J.

    1996-01-01

    The potential role of a crack arrest argument for the structural integrity assessments of steel pressure vessels and the relationship between crack initiation and crack arrest philosophies are described. A typical structural integrity assessment using crack initiation fracture mechanics is illustrated by means of a case study based on assessment of the steel pressure vessels for Magnox power stations. Evidence of the occurrence of crack arrest in structures is presented and reviewed, and the applications to pressure vessels which are subjected to similar conditions are considered. An outline is given of the material characterisation that would be required to undertake a crack arrest integrity assessment. It is concluded that crack arrest arguments could be significant in the structural integrity assessment of PWR reactor pressure vessels under thermal shock conditions, whereas for Magnox steel pressure vessels it would be limited in its potential to supporting existing arguments. (author)

  3. Investigation of a Water-Pond Arresting of a Dynamic Model of a Jet Transport

    Science.gov (United States)

    Thompson, William C.

    1961-01-01

    Brief dynamic-model tests have been made at the request of the Federal Aviation Agency to investigate the use of a shallow pond of water at the end of a runway as a means of arresting jet-transport aircraft when they are forced to abort on take-off or overrun on landing. Such a scheme is of particular interest for civil aircraft because it requires no modifications or attachments to the airplane and no mechanical devices in the arresting system. A modification of this scheme that uses a flexible plastic cover over the water surface has also been tested. The purpose of this paper is to present the results of a dynamic model investigation which would aid in determining whether the water-pond arresting system could be used as a means of arresting airplane overrun.

  4. Crack arrest toughness of structural steels evaluated by compact test

    International Nuclear Information System (INIS)

    Nakano, Yoshifumi; Tanaka, Michihiro

    1982-01-01

    Crack arrest tests such as compact, ESSO and DCB tests were made on SA533B Cl. 1, HT80 and KD32 steels to evaluate the crack arrest toughness. The main results obtained are as follows: (1) The crack arrest toughness could be evaluated by K sub(Ia) which was obtained by the static analysis of compact test. (2) K sub(ID) determined by the dynamic analysis of compact test was greater than K sub(Ia), though K sub(ID) became close to K sub(Ia)/K sub(Q) became a unity where K sub(Q) is the stress intensity factor at the crack initiation. (3) No significant difference was observed between K sub(Ia) and K sub(ca) obtained by ESSO and DCB tests, though K sub(ca) obtained by DCB test tended to be smaller than K sub(Ia) at lower temperatures. (4) K sub(Ia) was smaller than K sub(Ic) in the transition temperature range, while it was greater than K sub(Id). In the temperature range where K sub(Ic), which was determined from J sub(Ic), decreased with temperature increase, however, it was smaller than K sub(Ia). (5) The fracture appearance transition temperature and the absorbed energy obtained by 2 mm V-notch Charpy test were appropriate parameters for representing the crack arrest toughness, while the NDT temperature was not. (author)

  5. Dynamic Arrest in Charged Colloidal Systems Exhibiting Large-Scale Structural Heterogeneities

    International Nuclear Information System (INIS)

    Haro-Perez, C.; Callejas-Fernandez, J.; Hidalgo-Alvarez, R.; Rojas-Ochoa, L. F.; Castaneda-Priego, R.; Quesada-Perez, M.; Trappe, V.

    2009-01-01

    Suspensions of charged liposomes are found to exhibit typical features of strongly repulsive fluid systems at short length scales, while exhibiting structural heterogeneities at larger length scales that are characteristic of attractive systems. We model the static structure factor of these systems using effective pair interaction potentials composed of a long-range attraction and a shorter range repulsion. Our modeling of the static structure yields conditions for dynamically arrested states at larger volume fractions, which we find to agree with the experimentally observed dynamics

  6. Foam on troubled water: Capillary induced finite-time arrest of sloshing waves

    Science.gov (United States)

    Viola, Francesco; Brun, P.-T.; Dollet, Benjamin; Gallaire, François

    2016-09-01

    Interfacial forces exceed gravitational forces on a scale small relative to the capillary length—two millimeters in the case of an air-water interface—and therefore dominate the physics of sub-millimetric systems. They are of paramount importance for various biological taxa and engineering processes where the motion of a liquid meniscus induces a viscous frictional force that exhibits a sublinear dependence in the meniscus velocity, i.e., a power law with an exponent smaller than one. Interested in the fundamental implications of this dependence, we use a liquid-foam sloshing system as a prototype to exacerbate the effect of sublinear friction on the macroscopic mechanics of multi-phase flows. In contrast to classical theory, we uncover the existence of a finite-time singularity in our system yielding the arrest of the fluid's oscillations. We propose a minimal theoretical framework to capture this effect, thereby amending the paradigmatic damped harmonic oscillator model. Our results suggest that, although often not considered at the macroscale, sublinear capillary forces govern the friction at liquid-solid and liquid-liquid interfaces.

  7. Biofilm Community Dynamics in Bench-Scale Annular Reactors Simulating Arrestment of Chloraminated Drinking Water Nitrification

    Science.gov (United States)

    Annular reactors (ARs) were used to study biofilm community succession and provide an ecological insight during nitrification arrestment through simultaneously increasing monochloramine (NH2Cl) and chlorine to nitrogen mass ratios, resulting in four operational periods (I to IV)....

  8. Crack arrest: some comments on microscopic and macroscopic aspects in relation to the assurance of structural integrity

    Energy Technology Data Exchange (ETDEWEB)

    Lidbury, D.P.G.; Druce, S.G.; Tomkins, B. [AEA Technology, Risley (United Kingdom)

    1996-12-31

    Fracture prevention in high integrity structures in general, and steel nuclear reactor pressure vessels (RPVs) in particular, is based upon the avoidance of crack initiation, with due regard to real or postulated defects, material toughness and anticipated normal and off-normal loading conditions. However, avoidance of crack initiation can never be guaranteed in any absolute sense. Thus, in cases where there is the possibility of an initiated crack propagating by brittle, cleavage fracture, the crack arrest concept may be usefully applied to provide some additional assurance of structural integrity. Within this context, the mechanical processes operative during the initiation and arrest of cleavage cracks are briefly compared and contrasted. The empirical evidence for indexing and onset-of-upper-shelf temperature for initiation (OUST) and the crack arrest temperature (CAT) relative to the Pellini drop-weight nil-ductility transition temperature (NDTT) is examined, and estimates of the parameter (OUST-CAT) are made for a range of steels. In the light of this, correlations between small-scale tests and more structurally relevant, large-scale tests are examined in relation to both initiation- and arrest-based failure avoidance methodologies. (author).

  9. Colchicine promotes a change in chromosome structure without loss of sister chromatid cohesion in prometaphase I-arrested bivalents.

    Science.gov (United States)

    Rodríguez, E M; Parra, M T; Rufas, J S; Suja, J A

    2001-12-01

    In somatic cells colchicine promotes the arrest of cell division at prometaphase, and chromosomes show a sequential loss of sister chromatid arm and centromere cohesion. In this study we used colchicine to analyse possible changes in chromosome structure and sister chromatid cohesion in prometaphase I-arrested bivalents of the katydid Pycnogaster cucullata. After silver staining we observed that in colchicine-arrested prometaphase I bivalents, and in contrast to what was found in control bivalents, sister kinetochores appeared individualised and sister chromatid axes were completely separated all along their length. However, this change in chromosome structure occurred without loss of sister chromatid arm cohesion. We also employed the MPM-2 monoclonal antibody against mitotic phosphoproteins on control and colchicine-treated spermatocytes. In control metaphase I bivalents this antibody labelled the tightly associated sister kinetochores and the interchromatid domain. By contrast, in colchicine-treated prometaphase I bivalents individualised sister kinetochores appeared labelled, but the interchromatid domain did not show labelling. These results support the notion that MPM-2 phosphoproteins, probably DNA topoisomerase IIalpha, located in the interchromatid domain act as "chromosomal staples" associating sister chromatid axes in metaphase I bivalents. The disappearance of these chromosomal staples would induce a change in chromosome structure, as reflected by the separation of sister kinetochores and sister axes, but without a concomitant loss of sister chromatid cohesion.

  10. Strategies for reducing police arrest in the context of an HIV prevention programme for female sex workers: evidence from structural interventions in Karnataka, South India.

    Science.gov (United States)

    Bhattacharjee, Parinita; Isac, Shajy; McClarty, Leigh M; Mohan, Haranahalli L; Maddur, Srinath; Jagannath, Sunitha B; Venkataramaiah, Balasubramanya K; Moses, Stephen; Blanchard, James F; Gurnani, Vandana

    2016-01-01

    Female sex workers (FSWs) frequently experience violence in their work environments, violating their basic rights and increasing their vulnerability to HIV infection. Structural interventions addressing such violence are critical components of comprehensive HIV prevention programmes. We describe structural interventions developed to address violence against FSWs in the form of police arrest, in the context of the Bill and Melinda Gates Foundation's India AIDS Initiative (Avahan) in Karnataka, South India. We examine changes in FSW arrest between two consecutive time points during the intervention and identify characteristics that may increase FSW vulnerability to arrest in Karnataka. Structural interventions with police involved advocacy work with senior police officials, sensitization workshops, and integration of HIV and human rights topics in pre-service curricula. Programmes for FSWs aimed to enhance collectivization, empowerment and awareness about human rights and to introduce crisis response mechanisms. Three rounds of integrated behavioural and biological assessment surveys were conducted among FSWs from 2004 to 2011. We conducted bivariate and multivariate analyses using data from the second (R2) and third (R3) survey rounds to examine changes in arrests among FSWs over time and to assess associations between police arrest, and the sociodemographic and sex work-related characteristics of FSWs. Among 4110 FSWs surveyed, rates of ever being arrested by the police significantly decreased over time, from 9.9% in R2 to 6.1% in R3 (adjusted odds ratio (AOR) [95% CI]=0.63 [0.48 to 0.83]). Arrests in the preceding year significantly decreased, from 5.5% in R2 to 2.8% in R3 (AOR [95% CI]=0.59 [0.41 to 0.86]). FSWs arrested as part of arbitrary police raids also decreased from 49.6 to 19.5% (AOR [95% CI]=0.21 [0.11 to 0.42]). Certain characteristics, including financial dependency on sex work, street- or brothel-based solicitation and high client volumes, were found

  11. Daily Arrests

    Data.gov (United States)

    Montgomery County of Maryland — This dataset provides the public with arrest information from the Montgomery County Central Processing Unit (CPU) systems. The data presented is derived from every...

  12. Cardiac arrest

    Science.gov (United States)

    ... magnesium. These minerals help your heart's electrical system work. Abnormally high or low levels can cause cardiac arrest. Severe physical stress. Anything that causes a severe stress on your ...

  13. Water structure around trehalose

    Energy Technology Data Exchange (ETDEWEB)

    Pagnotta, S.E. [Dipartimento di Fisica ' E. Amaldi' , Universita di Roma Tre, Via della Vasca Navale 84, 00146 Roma (Italy); CNISM-CNR, Unita di Roma Tre, Via della Vasca Navale 84, 00146 Roma (Italy)], E-mail: pagnotta@fis.uniroma3.it; Ricci, M.A.; Bruni, F. [Dipartimento di Fisica ' E. Amaldi' , Universita di Roma Tre, Via della Vasca Navale 84, 00146 Roma (Italy); McLain, S. [ISIS Facility, Rutherford Appleton Laboratories, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Magazu, S. [Dipartimento di Fisica, Universita di Messina, C. da Papardo 31, 98166 Messina (Italy)

    2008-04-18

    A diluted solution of trehalose in water has been investigated by means of neutron diffraction with isotopic H/D substitution of the water hydrogens. Data have been analyzed in terms of site-site radial distribution functions, via the EPSR simulation code. This is the first time that the capabilities of this data refinement method are tested against neutron diffraction data of a complex carbohydrate molecule. A small perturbation of water hydration shell and short hydrogen bonds between trehalose oxygens and water hydrogens has been evidenced.

  14. The structure of liquid water

    International Nuclear Information System (INIS)

    Marin, B.

    1969-01-01

    We have tried to expose a bibliography so complete as possible on structure of liquid water. One synthesis of the different models of water structure is presently impossible, so, we have exposed the main properties of water. We have pointed out the new hypotheses on the electronic structure of water molecule and on the theory of hydrogen bond. After that, we have put together the studies of structure by spectroscopy and given the main deductions of some workers on this subject. We have also exposed the characteristics of processes: relaxation and dielectric constant, influence of temperature on structure. At last, we have considered briefly the partition and thermodynamic functions established from the various models proposed. (author) [fr

  15. Structurally simplified biphenyl combretastatin A4 derivatives retain in vitro anti-cancer activity dependent on mitotic arrest

    Science.gov (United States)

    Tarade, Daniel; Ma, Dennis; Pignanelli, Christopher; Mansour, Fadi; Simard, Daniel; van den Berg, Sean; Gauld, James; McNulty, James; Pandey, Siyaram

    2017-01-01

    The cis-stilbene, combretastatin A4 (CA4), is a potent microtubule targeting and vascular damaging agent. Despite promising results at the pre-clinical level and extensive clinical evaluation, CA4 has yet to be approved for therapeutic use. One impediment to the development of CA4 is an inherent conformational instability about the ethylene linker, which joins two aromatic rings. We have previously published preliminary data regarding structurally simplified biphenyl derivatives of CA4, lacking an ethylene linker, which retain anti-proliferative and pro-apoptotic activity, albeit at higher doses. Our current study provides a more comprehensive evaluation regarding the anti-proliferative and pro-apoptotic properties of biphenyl CA4 derivatives in both 2D and 3D cancerous and non-cancerous cell models. Computational analysis has revealed that cytotoxicity of CA4 and biphenyl analogues correlates with predicted tubulin affinity. Additional mechanistic evaluation of the biphenyl derivatives found that their anti-cancer activity is dependent on prolonged mitotic arrest, in a similar manner to CA4. Lastly, we have shown that cancer cells deficient in the extrinsic pathway of apoptosis experience delayed cell death following treatment with CA4 or analogues. Biphenyl derivatives of CA4 represent structurally simplified analogues of CA4, which retain a similar mechanism of action. The biphenyl analogues warrant in vivo examination to evaluate their potential as vascular damaging agents. PMID:28253265

  16. Structurally simplified biphenyl combretastatin A4 derivatives retain in vitro anti-cancer activity dependent on mitotic arrest.

    Directory of Open Access Journals (Sweden)

    Daniel Tarade

    Full Text Available The cis-stilbene, combretastatin A4 (CA4, is a potent microtubule targeting and vascular damaging agent. Despite promising results at the pre-clinical level and extensive clinical evaluation, CA4 has yet to be approved for therapeutic use. One impediment to the development of CA4 is an inherent conformational instability about the ethylene linker, which joins two aromatic rings. We have previously published preliminary data regarding structurally simplified biphenyl derivatives of CA4, lacking an ethylene linker, which retain anti-proliferative and pro-apoptotic activity, albeit at higher doses. Our current study provides a more comprehensive evaluation regarding the anti-proliferative and pro-apoptotic properties of biphenyl CA4 derivatives in both 2D and 3D cancerous and non-cancerous cell models. Computational analysis has revealed that cytotoxicity of CA4 and biphenyl analogues correlates with predicted tubulin affinity. Additional mechanistic evaluation of the biphenyl derivatives found that their anti-cancer activity is dependent on prolonged mitotic arrest, in a similar manner to CA4. Lastly, we have shown that cancer cells deficient in the extrinsic pathway of apoptosis experience delayed cell death following treatment with CA4 or analogues. Biphenyl derivatives of CA4 represent structurally simplified analogues of CA4, which retain a similar mechanism of action. The biphenyl analogues warrant in vivo examination to evaluate their potential as vascular damaging agents.

  17. Oscillating water column structural model

    Energy Technology Data Exchange (ETDEWEB)

    Copeland, Guild [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bull, Diana L [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jepsen, Richard Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gordon, Margaret Ellen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    An oscillating water column (OWC) wave energy converter is a structure with an opening to the ocean below the free surface, i.e. a structure with a moonpool. Two structural models for a non-axisymmetric terminator design OWC, the Backward Bent Duct Buoy (BBDB) are discussed in this report. The results of this structural model design study are intended to inform experiments and modeling underway in support of the U.S. Department of Energy (DOE) initiated Reference Model Project (RMP). A detailed design developed by Re Vision Consulting used stiffeners and girders to stabilize the structure against the hydrostatic loads experienced by a BBDB device. Additional support plates were added to this structure to account for loads arising from the mooring line attachment points. A simplified structure was designed in a modular fashion. This simplified design allows easy alterations to the buoyancy chambers and uncomplicated analysis of resulting changes in buoyancy.

  18. Nur77 forms novel nuclear structures upon DNA damage that cause transcriptional arrest

    International Nuclear Information System (INIS)

    Leseleuc, Louis de; Denis, Francois

    2006-01-01

    The orphan nuclear receptor Nur77 has been implicated in both growth and apoptosis, and its function and activity can be modulated by cellular redistribution. Green fluorescent protein-tagged Nur77 was used to evaluate the role of Nur77 intracellular redistribution in response to genotoxic stress. Selected DNA damaging agents and transcription inhibition lead to rapid redistribution of Nur77 into nuclear structures distinct from conventional nuclear bodies. These nuclear bodies formed transiently were tightly bound to the nuclear matrix and conditions that lead to their appearance were associated with Nur77 transcriptional inhibition. The formation of Nur77 nuclear bodies might be involved in programmed cell death modulation upon exposure to DNA damaging agents that inhibit transcription by sequestrating this proapoptotic factor in dense nuclear structures

  19. New insights into transcription fidelity: thermal stability of non-canonical structures in template DNA regulates transcriptional arrest, pause, and slippage.

    Science.gov (United States)

    Tateishi-Karimata, Hisae; Isono, Noburu; Sugimoto, Naoki

    2014-01-01

    The thermal stability and topology of non-canonical structures of G-quadruplexes and hairpins in template DNA were investigated, and the effect of non-canonical structures on transcription fidelity was evaluated quantitatively. We designed ten template DNAs: A linear sequence that does not have significant higher-order structure, three sequences that form hairpin structures, and six sequences that form G-quadruplex structures with different stabilities. Templates with non-canonical structures induced the production of an arrested, a slipped, and a full-length transcript, whereas the linear sequence produced only a full-length transcript. The efficiency of production for run-off transcripts (full-length and slipped transcripts) from templates that formed the non-canonical structures was lower than that from the linear. G-quadruplex structures were more effective inhibitors of full-length product formation than were hairpin structure even when the stability of the G-quadruplex in an aqueous solution was the same as that of the hairpin. We considered that intra-polymerase conditions may differentially affect the stability of non-canonical structures. The values of transcription efficiencies of run-off or arrest transcripts were correlated with stabilities of non-canonical structures in the intra-polymerase condition mimicked by 20 wt% polyethylene glycol (PEG). Transcriptional arrest was induced when the stability of the G-quadruplex structure (-ΔG°37) in the presence of 20 wt% PEG was more than 8.2 kcal mol(-1). Thus, values of stability in the presence of 20 wt% PEG are an important indicator of transcription perturbation. Our results further our understanding of the impact of template structure on the transcription process and may guide logical design of transcription-regulating drugs.

  20. Dynamic propagation and cleavage crack arrest in bainitic steel

    International Nuclear Information System (INIS)

    Hajjaj, M.

    2006-06-01

    In complement of the studies of harmfulness of defects, generally realized in term of initiation, the concept of crack arrest could be used as complementary analyses to the studies of safety. The stop occurs when the stress intensity factor becomes lower than crack arrest toughness (KIa) calculated in elasto-statics (KI ≤ KIa). The aim of this thesis is to understand and predict the stop of a crack propagating at high speed in a 18MND5 steel used in the pressure water reactor (PWR). The test chosen to study crack arrest is the disc thermal shock test. The observations under the scanning electron microscope of the fracture surface showed that the crack arrest always occurs in cleavage mode and that the critical microstructural entity with respect to the propagation and crack arrest corresponds to at least the size of the prior austenitic grain. The numerical analyses in elasto-statics confirm the conservatism of the codified curve of the RCC-M with respect to the values of KIa. The dynamic numerical analyses show that the deceleration of the crack measured at the end of the propagation is related to the global dynamic of the structure (vibrations). The transferability to components of crack arrest toughness obtained from tests analysed in static is thus not assured. The disc thermal shock tests were also modelled by considering a criterion of propagation and arrest of the type 'RKR' characterized by a critical stress sc which depends on the temperature. The results obtained account well for the crack jump measured in experiments as well as the shape of the crack arrest front. (author)

  1. Metoclopramide-induced cardiac arrest

    Directory of Open Access Journals (Sweden)

    Martha M. Rumore

    2011-11-01

    Full Text Available The authors report a case of cardiac arrest in a patient receiving intravenous (IV metoclopramide and review the pertinent literature. A 62-year-old morbidly obese female admitted for a gastric sleeve procedure, developed cardiac arrest within one minute of receiving metoclopramide 10 mg via slow intravenous (IV injection. Bradycardia at 4 beats/min immediately appeared, progressing rapidly to asystole. Chest compressions restored vital function. Electrocardiogram (ECG revealed ST depression indicative of myocardial injury. Following intubation, the patient was transferred to the intensive care unit. Various cardiac dysrrhythmias including supraventricular tachycardia (SVT associated with hypertension and atrial fibrillation occurred. Following IV esmolol and metoprolol, the patient reverted to normal sinus rhythm. Repeat ECGs revealed ST depression resolution without pre-admission changes. Metoclopramide is a non-specific dopamine receptor antagonist. Seven cases of cardiac arrest and one of sinus arrest with metoclopramide were found in the literature. The metoclopramide prescribing information does not list precautions or adverse drug reactions (ADRs related to cardiac arrest. The reaction is not dose related but may relate to the IV administration route. Coronary artery disease was the sole risk factor identified. According to Naranjo, the association was possible. Other reports of cardiac arrest, severe bradycardia, and SVT were reviewed. In one case, five separate IV doses of 10 mg metoclopramide were immediately followed by asystole repeatedly. The mechanism(s underlying metoclopramide’s cardiac arrest-inducing effects is unknown. Structural similarities to procainamide may play a role. In view of eight previous cases of cardiac arrest from metoclopramide having been reported, further elucidation of this ADR and patient monitoring is needed. Our report should alert clinicians to monitor patients and remain diligent in surveillance and

  2. Circulatory Arrest, Brain Arrest and Death Determination

    Directory of Open Access Journals (Sweden)

    Sam David Shemie

    2018-03-01

    Full Text Available Technological advances, particularly in the capacity to support, replace or transplant failing organs, continue to challenge and refine our understanding of human death. Given the ability to reanimate organs before and after death, both inside and outside of the body, through reinstitution of oxygenated circulation, concepts related to death of organs (e.g. cardiac death are no longer valid. This paper advances the rationale for a single conceptual determination of death related to permanent brain arrest, resulting from primary brain injury or secondary to circulatory arrest. The clinical characteristics of brain arrest are the permanent loss of capacity for consciousness and loss of all brainstem functions. In the setting of circulatory arrest, death occurs after the arrest of circulation to the brain rather than death of the heart. Correspondingly, any intervention that resumes oxygenated circulation to the brain after circulatory arrest would invalidate the determination of death.

  3. Focused and Corrective Feedback Versus Structured and Supported Debriefing in a Simulation-Based Cardiac Arrest Team Training: A Pilot Randomized Controlled Study.

    Science.gov (United States)

    Kim, Ji-Hoon; Kim, Young-Min; Park, Seong Heui; Ju, Eun A; Choi, Se Min; Hong, Tai Yong

    2017-06-01

    The aim of the study was to compare the educational impact of two postsimulation debriefing methods-focused and corrective feedback (FCF) versus Structured and Supported Debriefing (SSD)-on team dynamics in simulation-based cardiac arrest team training. This was a pilot randomized controlled study conducted at a simulation center. Fourth-year medical students were randomly assigned to the FCF or SSD group, with each team composed of six students and a confederate. Each team participated in two simulations and the assigned debriefing (FCF or SSD) sessions and then underwent a test simulation. Two trained raters blindly assessed all of the recorded simulations using checklists. The primary outcome was the improvement in team dynamics scores between baseline and test simulation. The secondary outcomes were improvements before and after training in team clinical performance scores, self-assessed comprehension of and confidence in cardiac arrest management and team dynamics, as well as evaluations of the postsimulation debriefing intervention. In total, 95 students participated [FCF (8 teams, n = 47) and SSD (8 teams, n = 48)]. The SSD team dynamics score during the test simulation was higher than at baseline [baseline: 74.5 (65.9-80.9), test: 85.0 (71.9-87.6), P = 0.035]. However, there were no differences in the improvement in the team dynamics or team clinical performance scores between the two groups (P = 0.328, respectively). There was no significant difference in improvement in team dynamics scores during the test simulation compared with baseline between the SSD and FCF groups in a simulation-based cardiac arrest team training in fourth-year Korean medical students.

  4. Scoulerine affects microtubule structure, inhibits proliferation, arrests cell cycle and thus culminates in the apoptotic death of cancer cells.

    Science.gov (United States)

    Habartova, Klara; Havelek, Radim; Seifrtova, Martina; Kralovec, Karel; Cahlikova, Lucie; Chlebek, Jakub; Cermakova, Eva; Mazankova, Nadezda; Marikova, Jana; Kunes, Jiri; Novakova, Lucie; Rezacova, Martina

    2018-03-19

    Scoulerine is an isoquinoline alkaloid, which indicated promising suppression of cancer cells growth. However, the mode of action (MOA) remained unclear. Cytotoxic and antiproliferative properties were determined in this study. Scoulerine reduces the mitochondrial dehydrogenases activity of the evaluated leukemic cells with IC 50 values ranging from 2.7 to 6.5 µM. The xCELLigence system revealed that scoulerine exerted potent antiproliferative activity in lung, ovarian and breast carcinoma cell lines. Jurkat and MOLT-4 leukemic cells treated with scoulerine were decreased in proliferation and viability. Scoulerine acted to inhibit proliferation through inducing G2 or M-phase cell cycle arrest, which correlates well with the observed breakdown of the microtubule network, increased Chk1 Ser345, Chk2 Thr68 and mitotic H3 Ser10 phosphorylation. Scoulerine was able to activate apoptosis, as determined by p53 upregulation, increase caspase activity, Annexin V and TUNEL labeling. Results highlight the potent antiproliferative and proapoptotic function of scoulerine in cancer cells caused by its ability to interfere with the microtubule elements of the cytoskeleton, checkpoint kinase signaling and p53 proteins. This is the first study of the mechanism of scoulerine at cellular and molecular level. Scoulerine is a potent antimitotic compound and that it merits further investigation as an anticancer drug.

  5. Water cooling of RF structures

    International Nuclear Information System (INIS)

    Battersby, G.; Zach, M.

    1994-06-01

    We present computer codes for heat transfer in water cooled rf cavities. RF parameters obtained by SUPERFISH or analytically are operated on by a set of codes using PLOTDATA, a command-driven program developed and distributed by TRIUMF [1]. Emphasis is on practical solutions with designer's interactive input during the computations. Results presented in summary printouts and graphs include the temperature, flow, and pressure data. (authors). 4 refs., 4 figs

  6. AFM Structural Characterization of Drinking Water Biofilm ...

    Science.gov (United States)

    Due to the complexity of mixed culture drinking water biofilm, direct visual observation under in situ conditions has been challenging. In this study, atomic force microscopy (AFM) revealed the three dimensional morphology and arrangement of drinking water relevant biofilm in air and aqueous solution. Operating parameters were optimized to improve imaging of structural details for a mature biofilm in liquid. By using a soft cantilever (0.03 N/m) and slow scan rate (0.5 Hz), biofilm and individual bacterial cell’s structural topography were resolved and continuously imaged in liquid without loss of spatial resolution or sample damage. The developed methodology will allow future in situ investigations to temporally monitor mixed culture drinking water biofilm structural changes during disinfection treatments. Due to the complexity of mixed culture drinking water biofilm, direct visual observation under in situ conditions has been challenging. In this study, atomic force microscopy (AFM) revealed the three dimensional morphology and arrangement of drinking water relevant biofilm in air and aqueous solution. Operating parameters were optimized to improve imaging of structural details for a mature biofilm in liquid. By using a soft cantilever (0.03 N/m) and slow scan rate (0.5 Hz), biofilm and individual bacterial cell’s structural topography were resolved and continuously imaged in liquid without loss of spatial resolution or sample damage. The developed methodo

  7. Perspective on the structure of liquid water

    International Nuclear Information System (INIS)

    Nilsson, A.; Pettersson, L.G.M.

    2011-01-01

    Graphical abstract: Liquid water can be described in a fluctuating inhomogeneous picture with two local structural motifs that are spatially separated. At ambient temperatures most molecules favor a closer packing than tetrahedral, with strongly distorted hydrogen bonds giving higher density (yellow), which allows the quantized librational modes to be excited and contribute to the entropy, but with enthalpically favored tetrahedrally bonded water patches appearing as fluctuations (blue), i.e. a competition between entropy and enthalpy. Upon cooling water the amount of molecules participating in tetrahedral structures and the size of the tetrahedral patches increase. Highlights: ► Two components maximizing either enthalpy (tetrahedral, low-density) or entropy (non-specific H-bonding, higher density). ► Interconvert discontinuously and ratio depends on temperature. ► Density fluctuations on 1 nm length scale. ► Increasing size in supercooled region. ► Connection to Widom line and 2nd critical point. - Abstract: We present a picture that combines discussions regarding the thermodynamic anomalies in ambient and supercooled water with recent interpretations of X-ray spectroscopy and scattering data of water in the ambient regime. At ambient temperatures most molecules favor a closer packing than tetrahedral, with strongly distorted hydrogen bonds, which allows the quantized librational modes to be excited and contribute to the entropy, but with enthalpically favored tetrahedrally bonded water patches appearing as fluctuations, i.e. a competition between entropy and enthalpy. Upon cooling water the amount of molecules participating in tetrahedral structures and the size of the tetrahedral patches increase. The two local structures are connected to the liquid–liquid critical point hypothesis in supercooled water corresponding to high density liquid and low density liquid. We will discuss the interpretation of X-ray absorption spectroscopy, X-ray emission

  8. Pittsburgh Police Arrest Data

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Arrest data contains information on people taken into custody by City of Pittsburgh police officers. More serious crimes such as felony offenses are more likely to...

  9. Modeling Equity for Alternative Water Rate Structures

    Science.gov (United States)

    Griffin, R.; Mjelde, J.

    2011-12-01

    The rising popularity of increasing block rates for urban water runs counter to mainstream economic recommendations, yet decision makers in rate design forums are attracted to the notion of higher prices for larger users. Among economists, it is widely appreciated that uniform rates have stronger efficiency properties than increasing block rates, especially when volumetric prices incorporate intrinsic water value. Yet, except for regions where water market purchases have forced urban authorities to include water value in water rates, economic arguments have weakly penetrated policy. In this presentation, recent evidence will be reviewed regarding long term trends in urban rate structures while observing economic principles pertaining to these choices. The main objective is to investigate the equity of increasing block rates as contrasted to uniform rates for a representative city. Using data from four Texas cities, household water demand is established as a function of marginal price, income, weather, number of residents, and property characteristics. Two alternative rate proposals are designed on the basis of recent experiences for both water and wastewater rates. After specifying a reasonable number (~200) of diverse households populating the city and parameterizing each household's characteristics, every household's consumption selections are simulated for twelve months. This procedure is repeated for both rate systems. Monthly water and wastewater bills are also computed for each household. Most importantly, while balancing the budget of the city utility we compute the effect of switching rate structures on the welfares of households of differing types. Some of the empirical findings are as follows. Under conditions of absent water scarcity, households of opposing characters such as low versus high income do not have strong preferences regarding rate structure selection. This changes as water scarcity rises and as water's opportunity costs are allowed to

  10. Appropriate administrative structures in harnessing water resources ...

    African Journals Online (AJOL)

    Appropriate administrative structures in harnessing water resources for sustainable growth in Nigeria. Lekan Oyebande. Abstract. No Abstract. Journal of Mining and Geology Vol. 42(1) 2006: 21-30. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  11. Crisis management during anaesthesia: cardiac arrest.

    Science.gov (United States)

    Runciman, W B; Morris, R W; Watterson, L M; Williamson, J A; Paix, A D

    2005-06-01

    Cardiac arrest attributable to anaesthesia occurs at the rate of between 0.5 and 1 case per 10 000 cases, tends to have a different profile to that of cardiac arrest occurring elsewhere, and has an in-hospital mortality of 20%. However, as individual practitioners encounter cardiac arrest rarely, the rapidity with which the diagnosis is made and the consistency of appropriate management varies considerably. To examine the role of a previously described core algorithm "COVER ABCD-A SWIFT CHECK", supplemented by a sub-algorithm for cardiac arrest, in the management of cardiac arrest occurring in association with anaesthesia. The potential performance of this structured approach for each the relevant incidents among the first 4000 reported to the Australian Incident Monitoring Study (AIMS) was compared with the actual management as reported by the anaesthetists involved. There were 129 reports of cardiac arrest associated with anaesthesia among the first 4000 AIMS incident reports. Identified aetiological factors were grouped into five categories: (1) anaesthetic technique (11 cases with this category alone; 32 with this and one or more of the other categories, representing 25% of all 129 cardiac arrests); (2) drug related (16; 32, 25%); (3) associated with surgical procedure (9; 29, 22%); (4) associated with pre-existing medical or surgical disease (30; 82, 64%); (5) unknown (8; 14, 11%). The "real life" presentation and management of cardiac arrest in association with anaesthesia differs substantially from that detailed in general published guidelines. Cardiac rhythms at the time were sinus bradycardia (23%); asystole (22%); tachycardia/ventricular tachycardia/ventricular fibrillation (14%); and normal (7%), with a further third unknown. Details of treatment were recorded in 110 reports; modalities employed included cardiac compression (72%); adrenaline (61%); 100% oxygen (58%); atropine (38%); intravenous fluids (25%), and electrical defibrillation (17%). There

  12. Analysis of fluid structural instability in water

    International Nuclear Information System (INIS)

    Piccirillo, N.

    1997-02-01

    Recent flow testing of stainless steel hardware in a high pressure/high temperature water environment produced an apparent fluid-structural instability. The source of instability was investigated by studying textbook theory and by performing NASTRAN finite element analyses. The modal analyses identified the mode that was being excited, but the flutter instability analysis showed that the design is stable if minimal structural damping is present. Therefore, it was suspected that the test hardware was the root cause of the instability. Further testing confirmed this suspicion

  13. Runway Arrested Landing Site (RALS)

    Data.gov (United States)

    Federal Laboratory Consortium — The Runway Arrested Landing Site includes an underground complex located on a Mod 2, Mod 3, and Mod 3+ arresting gear and are located under the runway and accurately...

  14. [Crystallographic evaluation of structural changes in water].

    Science.gov (United States)

    Farashchuk, N F; Rakhmanin, Yu A; Savostikova, O N; Telenkova, O G

    2014-01-01

    The study of the structural state of tap water that has been stored for two days in the packaging materials of various type and in different conditions, was performed with the use of crystallographic method for the investigation of liquids based on a special approach for dehydration of the drop, which is a fixed thin "slice" of the examines liquid. Most organized crystallographic pattern was shown to observe in a drop of water after treatment Bioptron lamp (content of liquid-crystal associates (LCA)--6.90 ± 0.23), and stored in a silver vessel (content LCA--6.28 ± 0.17), and the least organized, almost amorphous precipitate is formed in a drop of water stored in plastic containers (content LCA--2.92 ± 0.15%). Basing on the obtained results, it can be concluded that the crystallographic method can be used for the identification of qualitative changes occurring in liquid water under the influence of various physical factors, for the identification of the rationality of the use of hereafter sophisticated quantitative techniques.

  15. Structure of steam water mixture spray

    International Nuclear Information System (INIS)

    Mitsuhashi, Yuki; Mizutani, Hiroya; Sanada, Toshiyuki; Saito, Takayuki

    2008-01-01

    The flow structure of steam and water mixture spray is studied both numerically and experimentally. The velocity and pressure profiles of the single phase flow are calculated using numerical methods. Using calculated flow fields, the droplet behavior is predicted by the one-way interaction model. This numerical analysis clarifies that the droplets are still accelerated after they are sprayed from the nozzle. In the experiments, the spray of the mixture is observed by using ultra high-speed video camera, and the velocity field is measured by using PIV technique. Along with this PIV velocity field measurement, the velocities and diameters of droplets are measured by phase Doppler anemometry. Furthermore, mixing process of steam and water, and atomization process of liquid film are observed through the transparent nozzle. The high-speed photography observation reveals that the flow inside the nozzle forms the annular flow and the most of the liquid film is atomized at the nozzle outlet. Finally, the optimum method of processing mixture of steam and water is proposed. (author)

  16. Arresting relaxation in Pickering Emulsions

    Science.gov (United States)

    Atherton, Tim; Burke, Chris

    2015-03-01

    Pickering emulsions consist of droplets of one fluid dispersed in a host fluid and stabilized by colloidal particles absorbed at the fluid-fluid interface. Everyday materials such as crude oil and food products like salad dressing are examples of these materials. Particles can stabilize non spherical droplet shapes in these emulsions through the following sequence: first, an isolated droplet is deformed, e.g. by an electric field, increasing the surface area above the equilibrium value; additional particles are then adsorbed to the interface reducing the surface tension. The droplet is then allowed to relax toward a sphere. If more particles were adsorbed than can be accommodated by the surface area of the spherical ground state, relaxation of the droplet is arrested at some non-spherical shape. Because the energetic cost of removing adsorbed colloids exceeds the interfacial driving force, these configurations can remain stable over long timescales. In this presentation, we present a computational study of the ordering present in anisotropic droplets produced through the mechanism of arrested relaxation and discuss the interplay between the geometry of the droplet, the dynamical process that produced it, and the structure of the defects observed.

  17. The geometry of empty space is the key to arresting dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Lawlor, Aonghus; De Gregorio, Paolo; Dawson, K A [Department of Chemistry, University College Dublin, Irish Centre for Colloid Science and Biomaterials, Belfield, Dublin 4 (Ireland)

    2004-10-27

    We present the concept of dynamically available volume as a suitable order parameter for dynamical arrest. We show that dynamical arrest can be understood as a de-percolation transition of a vacancy network or available space. Beyond the arrest transition we find that droplets of available space are disconnected and the dynamics is frozen. This connection of the dynamics to the underlying geometrical structure of empty space provides us with a rich framework for studying the arrest transition.

  18. Shock wave focusing in water inside convergent structures

    Directory of Open Access Journals (Sweden)

    C Wang

    2016-09-01

    Full Text Available Experiments on shock focusing in water-filled convergent structures have been performed. A shock wave in water is generated by means of a projectile, launched from a gas gun, which impacts a water-filled convergent structure. Two types of structures have been tested; a bulk material and a thin shell structure. The geometric shape of the convergent structures is given by a logarithmic spiral, and this particular shape is chosen because it maximizes the amount of energy reaching the focal region. High-speed schlieren photography is used to visualize the shock dynamics during the focusing event. Results show that the fluid-structure interaction between the thin shell structure and the shock wave in the water is different from that of a bulk structure; multiple reflections of the shock wave inside the thin shell are reflected back into the water, thus creating a wave train, which is not observed for shock focusing in a bulk material.

  19. Water stale and structure analysis of Konjac irradiation copolymer

    International Nuclear Information System (INIS)

    Geng Shengrong; Xia Hezhou; Chen Xueling; Ye Lixiu; Hua Yuejin

    2011-01-01

    To study the absorption performance of Konjac-AA copolymer prepared by using irradiation, the water absorption capacity, sorbent speed and water keeping ability were determined, DSC and TEM analysis were used to investigate the water content and structure characters. The results showed that the largest water absorption speed was 16 g · -1 · min -1 at room temperature, and the largest water absorption was 400 times within 60 minutes. The water absorption was affected by granularity, temperature, ion content and ion type, especially the ion type. The water keeping ability was affected by temperature and time, which was up to 35% of absorbed water when the fully water absorbed copolymer was kept under room temperature for 15 d. The free and bounder water content which could be assimilated by the plants was 99.617%. The water stale copolymer has a three-dimensional spiral structure. (authors)

  20. Structure of water and the thermodynamics of aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Nemethy, G.

    1970-10-26

    This report represents the summary of a series of lectures held at the Istituto Superiore di Sanita, Laboratori di Fisica, from 18 September to 26 October 1970. The topics discussed were: Intermolecular forces, the individual water molecule and the hydrogen bond, the structures of the solid phases of water, experimental information on the strucuture of liquid water, theoretical models of water structure, experimental properties and theoretical models of aqueous solutions of nonpolar solutes, polar solutes, and electrolytes, the conformational stability of biological macromolecules.

  1. Cardiac arrest – cardiopulmonary resuscitation

    Directory of Open Access Journals (Sweden)

    Basri Lenjani

    2014-01-01

    Conclusions: All survivors from cardiac arrest have received appropriate medical assistance within 10 min from attack, which implies that if cardiac arrest occurs near an institution health care (with an opportunity to provide the emergent health care the rate of survival is higher.

  2. Polyamide membranes with nanoscale Turing structures for water purification

    Science.gov (United States)

    Tan, Zhe; Chen, Shengfu; Peng, Xinsheng; Zhang, Lin; Gao, Congjie

    2018-05-01

    The emergence of Turing structures is of fundamental importance, and designing these structures and developing their applications have practical effects in chemistry and biology. We use a facile route based on interfacial polymerization to generate Turing-type polyamide membranes for water purification. Manipulation of shapes by control of reaction conditions enabled the creation of membranes with bubble or tube structures. These membranes exhibit excellent water-salt separation performance that surpasses the upper-bound line of traditional desalination membranes. Furthermore, we show the existence of high water permeability sites in the Turing structures, where water transport through the membranes is enhanced.

  3. Cardiac Arrest: MedlinePlus Health Topic

    Science.gov (United States)

    ... Handouts Cardiac arrest (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Cardiac Arrest updates ... this? GO MEDICAL ENCYCLOPEDIA Cardiac arrest Related Health Topics Arrhythmia CPR Pacemakers and Implantable Defibrillators National Institutes ...

  4. Post-resuscitation care for survivors of cardiac arrest

    Directory of Open Access Journals (Sweden)

    Ashvarya Mangla

    2014-01-01

    Full Text Available Cardiac arrest can occur following a myriad of clinical conditions. With advancement of medical science and improvements in Emergency Medical Services systems, the rate of return of spontaneous circulation for patients who suffer an out-of-hospital cardiac arrest (OHCA continues to increase. Managing these patients is challenging and requires a structured approach including stabilization of cardiopulmonary status, early consideration of neuroprotective strategies, identifying and managing the etiology of arrest and initiating treatment to prevent recurrence. This requires a closely coordinated multidisciplinary team effort. In this article, we will review the initial management of survivors of OHCA, highlighting advances and ongoing controversies.

  5. Can we describe graphene confined water structures as overlapping of approaching graphene-water interfacial structures?

    Energy Technology Data Exchange (ETDEWEB)

    Chialvo, Ariel A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Vlcek, Lukas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-03-21

    We investigate the microscopic mechanisms of the overlap of interfacial structures in confined fluids and attempt to answer the question whether the confined structures can be predicted from the original density profiles of individual solid-fluid interfaces. For that purpose we perform (globally) isobaricisothermal (locally, grand canonical) molecular dynamics simulations to extract not only the axial distribution functions of the water-sites for the uncoupled graphene-water interfaces, but also those corresponding to the confined aqueous environments over the interplate range 8 ≤ h(Å) ≤ 28 typically at ambient conditions. We have tested two (i.e., an arithmetic and a geometric) superposition approximations for the singlet density of confined water between flat graphene plates, as well as for a combination of flat and corrugated graphene plates. The outcome of this study suggests that the answer to the title’s question is a “yes”, provided that the interplate distance h is large enough to avoid fluid geometric packing frustration.

  6. Structural and functional significance of water permeation through cotransporters

    DEFF Research Database (Denmark)

    Zeuthen, Thomas; Gorraitz, Edurne; Her, Ka

    2016-01-01

    Membrane transporters, in addition to their major role as specific carriers for ions and small molecules, can also behave as water channels. However, neither the location of the water pathway in the protein nor their functional importance is known. Here, we map the pathway for water and urea...... through the intestinal sodium/glucose cotransporter SGLT1. Molecular dynamics simulations using the atomic structure of the bacterial transporter vSGLT suggest that water permeates the same path as Na+ and sugar. On a structural model of SGLT1, based on the homology structure of vSGLT, we identified...... to be due to alterations in steric hindrance to water and urea, and/or changes in protein folding caused by mismatching of side chains in the water pathway. Water permeation through SGLT1 and other transporters bears directly on the structural mechanism for the transport of polar solutes through...

  7. "House Arrest" or "Developmental Arrest"? A Study of Youth Under House Arrest.

    Science.gov (United States)

    Chamiel, Elad; Walsh, Sophie D

    2018-06-01

    Studies have examined the potential benefits and risks of alternative forms of detention, such as house arrest, for adults but, despite its growing use, little research has examined the implications of house arrest for juveniles. The current research examined the experience of 14 adolescents under house arrest. Six main themes were identified in the narratives of the participants: the experience of detention, daily schedule and utilization of time, emotions and self-reflection, relationships with peers, relation to parents and supervisor(s), and contact with professionals. Findings emphasized the potential developmental dangers of house arrest at the critical stage of adolescence. Yet, analysis also showed that the period of house arrest has the potential to be a period of positive changes, and can be used for successful rehabilitation.

  8. Sudden Cardiac Arrest during Participation in Competitive Sports.

    Science.gov (United States)

    Landry, Cameron H; Allan, Katherine S; Connelly, Kim A; Cunningham, Kris; Morrison, Laurie J; Dorian, Paul

    2017-11-16

    arrest during participation in competitive sports was 0.76 cases per 100,000 athlete-years. The occurrence of sudden cardiac arrest due to structural heart disease was uncommon during participation in competitive sports. (Funded by the National Heart, Lung, and Blood Institute and others.).

  9. Water polygons in high-resolution protein crystal structures.

    Science.gov (United States)

    Lee, Jonas; Kim, Sung-Hou

    2009-07-01

    We have analyzed the interstitial water (ISW) structures in 1500 protein crystal structures deposited in the Protein Data Bank that have greater than 1.5 A resolution with less than 90% sequence similarity with each other. We observed varieties of polygonal water structures composed of three to eight water molecules. These polygons may represent the time- and space-averaged structures of "stable" water oligomers present in liquid water, and their presence as well as relative population may be relevant in understanding physical properties of liquid water at a given temperature. On an average, 13% of ISWs are localized enough to be visible by X-ray diffraction. Of those, averages of 78% are water molecules in the first water layer on the protein surface. Of the localized ISWs beyond the first layer, almost half of them form water polygons such as trigons, tetragons, as well as expected pentagons, hexagons, higher polygons, partial dodecahedrons, and disordered networks. Most of the octagons and nanogons are formed by fusion of smaller polygons. The trigons are most commonly observed. We suggest that our observation provides an experimental basis for including these water polygon structures in correlating and predicting various water properties in liquid state.

  10. Structure and stability of spiro-cyclic water clusters

    Indian Academy of Sciences (India)

    Administrator

    Abstract. The structure and stability of spiro-cyclic water clusters containing up to 32 water molecules have been ... due to its importance in various real life systems. 1–8. High level ... It is well-known from the crystal structure data- base that the ...

  11. Structural transition in alcohol–water binary mixtures: A ...

    Indian Academy of Sciences (India)

    WINTEC

    Abstract. The strengthening of the hydrogen bonding (H-bond) network as well as transition from the tetrahedral-like water network to the zigzag chain structure of alcohol upon increasing the alcohol con- centration in ethanol–water and tertiary butanol (TBA) – water mixtures have been studied by using both steady state ...

  12. Enhanced water desalination performance through hierarchically-structured ceramic membranes

    NARCIS (Netherlands)

    Liu, Tong; Lei, Libin; Gu, Jianqiang; Wang, Yao; Winnubst, Louis; Chen, Chusheng; Ye, Chunsong; Chen, Fanglin

    2017-01-01

    Developments of membrane water desalination are impeded by low water vapor flux across the membrane. We present an innovative membrane design to significantly enhance the water vapor flux. A bilayer zirconia-based membrane with a thick hierarchically-structured support and a thin functional layer is

  13. Structure-function relationships in sapwood water transport and storage.

    Science.gov (United States)

    Barbara L. Gartner; Frederick C. Meinzer

    2005-01-01

    Primary production by plants requires the loss of substantial quantities of water when the stomata are open for carbon assimilation. The delivery of that water to the leaves occurs through the xylem. The structure, condition, and quantity of the xylem control not only the transport efficiency but also the release of water from storage. For example, if there is high...

  14. Interfacial crack arrest in sandwich beams subjected to fatigue loading using a novel crack arresting device – Numerical modelling

    DEFF Research Database (Denmark)

    Martakos, G.; Andreasen, J.H.; Berggreen, Christian

    2017-01-01

    A novel crack arresting device is implemented in foam-cored composite sandwich beams and tested using the Sandwich Tear Test (STT) configuration. A finite element model of the setup is developed, and the predictions are correlated with observations and results from a recently conducted experiment...... concept, as well as a design tool that can be used for the implementation of crack arresting devises in engineering applications of sandwich components and structures....

  15. Water's Interfacial Hydrogen Bonding Structure Reveals the Effective Strength of Surface-Water Interactions.

    Science.gov (United States)

    Shin, Sucheol; Willard, Adam P

    2018-06-05

    We combine all-atom molecular dynamics simulations with a mean field model of interfacial hydrogen bonding to analyze the effect of surface-water interactions on the structural and energetic properties of the liquid water interface. We show that the molecular structure of water at a weakly interacting ( i.e., hydrophobic) surface is resistant to change unless the strength of surface-water interactions are above a certain threshold. We find that below this threshold water's interfacial structure is homogeneous and insensitive to the details of the disordered surface, however, above this threshold water's interfacial structure is heterogeneous. Despite this heterogeneity, we demonstrate that the equilibrium distribution of molecular orientations can be used to quantify the energetic component of the surface-water interactions that contribute specifically to modifying the interfacial hydrogen bonding network. We identify this specific energetic component as a new measure of hydrophilicity, which we refer to as the intrinsic hydropathy.

  16. Ground water work breakdown structure dictionary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    This report contains the activities that are necessary to assess in ground water remediation as specified in the UMTRA Project. These activities include the following: site characterization; remedial action compliance and design documentation; environment, health, and safety program; technology assessment; property access and acquisition activities; site remedial actions; long term surveillance and licensing; and technical and management support.

  17. Ground water work breakdown structure dictionary

    International Nuclear Information System (INIS)

    1995-04-01

    This report contains the activities that are necessary to assess in ground water remediation as specified in the UMTRA Project. These activities include the following: site characterization; remedial action compliance and design documentation; environment, health, and safety program; technology assessment; property access and acquisition activities; site remedial actions; long term surveillance and licensing; and technical and management support

  18. Effect of sprinkler structure on water distribution uniformity

    International Nuclear Information System (INIS)

    Xu, M; Li, H; Chen, C; Tu, Q; Liu, J P

    2012-01-01

    Structures of sprinklers play important roles in the uniformity of water distribution. The advances and achievements to improve the distribution uniformity through the innovation in the sprinkler structures at home and abroad were presented in details. Analyses showed that three types of structure can ameliorate the water distribution efficiently. First, novel nozzle structures were applied, including the application of non-circle nozzle and special spread nozzles. Second, new structures of flow channel were used. Third, assistant device was added so as to improve the uneven water distribution, such as an assistant stream interrupter, pressure or flow rate regulator and so on. Compared to domestic sprinklers, sprinklers produced abroad have novel and special structures with better hydraulic performance. Basic theoretical researches should be strengthened and new materials, new manufacturing processes and new technique should be applied. Then new kinds of sprinkler will be produced and the hydraulic performance of sprinklers will be promoted to a higher level.

  19. Structural properties of water around uncharged and charged carbon nanotubes

    International Nuclear Information System (INIS)

    Dezfoli, Amir Reza Ansari; Mehrabian, Mozaffar Ali; Rafsanjani, Hassan Hashemipour

    2013-01-01

    Studying the structural properties of water molecules around the carbon nanotubes is very important in a wide variety of carbon nanotubes applications. We studied the number of hydrogen bonds, oxygen and hydrogen density distributions, and water orientation around carbon nanotubes. The water density distribution for all carbon nanotubes was observed to have the same feature. In water-carbon nanotubes interface, a high-density region of water molecules exists around carbon nanotubes. The results reveal that the water orientation around carbon nanotubes is roughly dependent on carbon nanotubes surface charge. The water molecules in close distances to carbon nanotubes were found to make an HOH plane nearly perpendicular to the water-carbon nanotubes interface for carbon nanotubes with negative surface charge. For uncharged carbon nanotubes and carbon nanotubes with positive surface charge, the HOH plane was in tangential orientation with water-carbon nanotubes interface. There was also a significant reduction in hydrogen bond of water region around carbon nanotubes as compared with hydrogen bond in bulk water. This reduction was very obvious for carbon nanotubes with positive surface charge. In addition, the calculation of dynamic properties of water molecules in water-CNT interface revealed that there is a direct relation between the number of Hbonds and self-diffusion coefficient of water molecules

  20. Modeling of soil-water-structure interaction

    DEFF Research Database (Denmark)

    Tang, Tian

    as the developed nonlinear soil displacements and stresses under monotonic and cyclic loading. With the FVM nonlinear coupled soil models as a basis, multiphysics modeling of wave-seabed-structure interaction is carried out. The computations are done in an open source code environment, OpenFOAM, where FVM models...

  1. Structured ecosystem-scale approach to marine water quality management

    CSIR Research Space (South Africa)

    Taljaard, Susan

    2006-10-01

    Full Text Available and implement environmental management programmes. A structured ecosystem-scale approach for the design and implementation of marine water quality management programmes developed by the CSIR (South Africa) in response to recent advances in policies...

  2. Structures of water molecular nanotube induced by axial tensile strains

    Energy Technology Data Exchange (ETDEWEB)

    Li, H. [Key Laboratory of Liquid Structures and Heredity of Materials, Ministry of Education, School of Materials Science and Engineering, Shandong University (China)], E-mail: lihuilmy@hotmail.com; Zhang, X.Q. [Physics Department, Ocean University of China, Qingdao (China); Liew, K.M. [Department of Building and Constructions, City University of Hong Kong, Kowloon (Hong Kong); Liu, X.F. [Key Laboratory of Liquid Structures and Heredity of Materials, Ministry of Education, School of Materials Science and Engineering, Shandong University (China)

    2008-10-06

    Five well-ordered nano-ice structures embedded in carbon nanotubes are obtained in this study. These five nano-ice phases all exhibit single walled tubular morphologies, including the pentagon, hexagon ice nanotubes whose structures are quite different from bulk ice. Our simulation results indicate that water molecules tend to rearrange into surface ring structures to reduce the number of free OH groups. The structural behavior of these ice nanotubes inside CNTs subject to axial stress is also investigated. The ice nanotubes tend to be drawn to ice nanorings or ice nanospring during the mechanical stretching. The distribution function exhibits typical order-to-disorder transition of the water network confined in carbon nanotube during the stretching. By analysis, we suggest that it is unlikely that additional water molecules will enter the tubes because of the increased volume available if the tubes are stretched at contact with a water reservoir.

  3. Hydrogen/deuterium substitution methods: understanding water structure in solution

    International Nuclear Information System (INIS)

    Soper, A.K.

    1993-01-01

    The hydrogen/deuterium substitution method has been used for different applications, such as the short range order between water molecules in a number of different environments (aqueous solutions of organic molecules), or to study the partial structure factors of water at high pressure and temperature. The absolute accuracy that can be obtained remains uncertain, but important qualitative information can be obtained on the local organization of water in aqueous solution. Some recent results with pure water, methanol and dimethyl sulphoxide (DMSO) solutions are presented. It is shown that the short range water structure is not greatly affected by most solutes except at high concentrations and when the solute species has its own distinctive interaction with water (such as a dissolved small ion). 3 figs., 14 refs

  4. Identification of structural relaxation in the dielectric response of water

    DEFF Research Database (Denmark)

    Hansen, Jesper Schmidt; Kisliuk, Alexander; Solokov, Alexei P.

    2016-01-01

    One century ago pioneering dielectric results obtained for water and n-alcohols triggered the advent of molecular rotation diffusion theory considered by Debye to describe the primary dielectric absorption in these liquids. Comparing dielectric, viscoelastic, and light scattering results, we...... unambiguously demonstrate that the structural relaxation appears only as a high-frequency shoulder in the dielectric spectra of water. In contrast, the main dielectric peak is related to a supramolecular structure, analogous to the Debye-like peak observed in monoalcohols....

  5. Structures of water molecules in carbon nanotubes under electric fields

    International Nuclear Information System (INIS)

    Winarto,; Takaiwa, Daisuke; Yamamoto, Eiji; Yasuoka, Kenji

    2015-01-01

    Carbon nanotubes (CNTs) are promising for water transport through membranes and for use as nano-pumps. The development of CNT-based nanofluidic devices, however, requires a better understanding of the properties of water molecules in CNTs because they can be very different from those in the bulk. Using all-atom molecular dynamics simulations, we investigate the effect of axial electric fields on the structure of water molecules in CNTs having diameters ranging from (7,7) to (10,10). The water dipole moments were aligned parallel to the electric field, which increases the density of water inside the CNTs and forms ordered ice-like structures. The electric field induces the transition from liquid to ice nanotubes in a wide range of CNT diameters. Moreover, we found an increase in the lifetime of hydrogen bonds for water structures in the CNTs. Fast librational motion breaks some hydrogen bonds, but the molecular pairs do not separate and the hydrogen bonds reform. Thus, hydrogen bonds maintain the water structure in the CNTs, and the water molecules move collectively, decreasing the axial diffusion coefficient and permeation rate

  6. Structure and optical properties of water covered Cu(110) surfaces

    International Nuclear Information System (INIS)

    Baghbanpourasl, A.

    2014-01-01

    In this thesis structural and optical properties of the water covered Cu(110) surface is studied using density functional theory within independent particle approximation. Several stable adsorption structures are studied such as water clusters (monomer, dimer, trimer, tetramer and pentamer), different hexagonal monolayers, partially dissociated water monolayers and three different types of chains among them a chain that consists of pentagon rings. For a copper surface in contact with water vapor, the energetically stable H 2 O/OH adsorbed structures are compared thermodynamically using adsorption free energy (change of free energy due to adsorption). Several phase diagrams with respect to temperature and pressure are calculated. It is found that among the large number of energetically stable structures (i.e. structures with positive adsorption energy ) only limited number of them are thermodynamically stable. These thermodynamically stable structures are the class of almost energetically degenerate hexagonal overlayers, one type of partially dissociated water structure that contains Bjerrum defect in the hydrogen bond network and pentagon chain. Since hydrogen atoms are light weight their vibrational effects can be considerable. Zero point vibration decreases the adsorption energy up to 0.1 eV and free energy of adsorbed molecules arising from vibrational degree of freedom can go up to -0.2 eV per adsorbed molecule at 500 Kelvin. However zero point energy and vibrational free energy of adsorbed molecules do not alter relative stability of the adsorbed structures. To account for the long range van der Waals interactions, a semi-empirical scheme is applied. Reflectance Anisotropy Spectroscopy (RAS) is a fast and non destructive optical method that can be used to prob the surface in different conditions such as vacuum and electro-chemical environment. Elasto-optic coeficients of bulk are calculated from first principles and the change of the RA spectrum of the bare Cu

  7. The neighborhood context of racial and ethnic disparities in arrest.

    Science.gov (United States)

    Kirk, David S

    2008-02-01

    This study assesses the role of social context in explaining racial and ethnic disparities in arrest, with afocus on how distinct neighborhood contexts in which different racial and ethnic groups reside explain variations in criminal outcomes. To do so, I utilize a multilevel, longitudinal research design, combining individual-level data with contextual data from the Project on Human Development in Chicago Neighborhoods (PHDCN). Findings reveal that black youths face multiple layers of disadvantage relative to other racial and ethnic groups, and these layers work to create differences in arrest. At the family level, results show that disadvantages in the form of unstable family structures explain much of the disparities in arrest across race and ethnicity. At the neighborhood level, black youths tend to reside in areas with both significantly higher levels of concentrated poverty than other youths as well as lower levels of collective efficacy than white youths. Variations in neighborhood tolerance of deviance across groups explain little of the arrest disparities, yet tolerance of deviance does influence the frequency with which a crime ultimately ends in an arrest. Even after accounting for relevant demographic, family, and neighborhood-level predictors, substantial residual arrest differences remain between black youths and youths of other racial and ethnic groups.

  8. Water relations, thallus structure and photosynthesis in Negev Desert lichens

    Science.gov (United States)

    Palmer, R. J. Jr; Friedmann, E. I.

    1990-01-01

    The role of lichen thallus structure in water relations and photosynthesis was studied in Ramalina maciformis (Del.) Bory and Teloschistes lacunosus (Rupr.) Sav. Water-vapour adsorption and photosynthesis are dependent upon thallus integrity and are significantly lower in crushed thalli. Cultured phycobiont (Trebouxia sp.) cells are capable of photosynthesis over the same relative humidity range (> 80% RH) as are intact lichens. Thus, water-vapour adsorption by the thallus and physiological adaptation of the phycobiont contribute to the ability of these lichens to photosynthesize in an arid environment. Despite differences in their anatomical structure and water-uptake characteristics, their CO2 incorporation is similar. The two lichens use liquid water differently and they occupy different niches.

  9. Structural and mechanical properties of glassy water in nanoscale confinement.

    Science.gov (United States)

    Lombardo, Thomas G; Giovambattista, Nicolás; Debenedetti, Pablo G

    2009-01-01

    We investigate the structure and mechanical properties of glassy water confined between silica-based surfaces with continuously tunable hydrophobicity and hydrophilicity by computing and analyzing minimum energy, mechanically stable configurations (inherent structures). The structured silica substrate imposes long-range order on the first layer of water molecules under hydrophobic confinement at high density (p > or = 1.0 g cm(-3)). This proximal layer is also structured in hydrophilic confinement at very low density (p approximately 0.4 g cm(-3)). The ordering of water next to the hydrophobic surface greatly enhances the mechanical strength of thin films (0.8 nm). This leads to a substantial stress anisotropy; the transverse strength of the film exceeds the normal strength by 500 MPa. The large transverse strength results in a minimum in the equation of state of the energy landscape that does not correspond to a mechanical instability, but represents disruption of the ordered layer of water next to the wall. In addition, we find that the mode of mechanical failure is dependent on the type of confinement. Under large lateral strain, water confined by hydrophilic surfaces preferentially forms voids in the middle of the film and fails cohesively. In contrast, water under hydrophobic confinement tends to form voids near the walls and fails by loss of adhesion.

  10. Sudden Cardiac Arrest (SCA) Risk Assessment

    Science.gov (United States)

    ... HRS Find a Specialist Share Twitter Facebook SCA Risk Assessment Sudden Cardiac Arrest (SCA) occurs abruptly and without ... people of all ages and health conditions. Start Risk Assessment The Sudden Cardiac Arrest (SCA) Risk Assessment Tool ...

  11. Bond-Valence Constraints on Liquid Water Structure

    International Nuclear Information System (INIS)

    Bickmore, Barry R.; Rosso, Kevin M.; Brown, I. David; Kerisit, Sebastien N.

    2009-01-01

    The recent controversy about the structure of liquid water pits a new model involving water molecules in relatively stable rings-and-chains structures against the standard model that posits water molecules in distorted tetrahedral coordination. Molecular dynamics (MD) simulations 'both classical and ab initio' almost uniformly support the standard model, but since none of them can yet reproduce all the anomalous properties of water, they leave room for doubt. We argue that it is possible to evaluate these simulations by testing them against their adherence to the bond-valence model, a well known, and quantitatively accurate, empirical summary of the behavior of atoms in the bonded networks of inorganic solids. Here we use the results of ab initio molecular dynamics simulations of ice, water, and several solvated aqueous species to show that the valence sum rule (the first axiom of the bond-valence model,) is followed in both solid and liquid bond networks. We then test MD simulations of water, employing several popular potential models, against this criterion and the experimental O-O radial distribution function. It appears that most of those tested cannot satisfy both criteria well, except TIP4P and TIP5P. If the valence sum rule really can be applied to simulated liquid structures, then it follows that the bonding behaviors of atoms in liquids are in some ways identical to those in solids. We support this interpretation by showing that the simulations produce O-H-O geometries completely consistent with the range of geometries available in solids, and the distributions of instantaneous valence sums reaching the atoms in both the ice and liquid water simulations are essentially identical. Taken together, this is powerful evidence in favor of the standard distorted tetrahedral model of liquid water structure

  12. The effect of the water tariff structures on the water consumption in Mallorcan hotels

    Science.gov (United States)

    Deyà-Tortella, Bartolomé; Garcia, Celso; Nilsson, William; Tirado, Dolores

    2016-08-01

    Tourism increases water demand, especially in coastal areas and on islands, and can also cause water shortages during the dry season and the degradation of the water supply. The aim of this study is to evaluate the impact of water price structures on hotel water consumption on the island of Mallorca (Spain). All tourist municipalities on the island use different pricing structures, such as flat or block rates, and different tariffs. This exogenous variation is used to evaluate the effect of prices on water consumption for a sample of 134 hotels. The discontinuity of the water tariff structure and the fixed rate, which depends on the number of hotel beds, generate endogeneity problems. We propose an econometric model, an instrumental variable quantile regression for within artificial blocks transformed data, to solve both problems. The coefficients corresponding to the price variables are not found to be significantly different from zero. The sign of the effect is negative, but the magnitude is negligible: a 1% increase in all prices would reduce consumption by an average of only 0.024%. This result is probably due to the small share of water costs with respect to the total hotel operational costs (around 4%). Our regression model concludes that the introduction of water-saving initiatives constitutes an effective way to reduce consumption.

  13. Water-insoluble Silk Films with Silk I Structure

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Q.; Hu, X; Wang, X; Kluge, J; Lu, S; Cebe, P; Kaplan, D

    2010-01-01

    Water-insoluble regenerated silk materials are normally produced by increasing the {beta}-sheet content (silk II). In the present study water-insoluble silk films were prepared by controlling the very slow drying of Bombyx mori silk solutions, resulting in the formation of stable films with a predominant silk I instead of silk II structure. Wide angle X-ray scattering indicated that the silk films stabilized by slow drying were mainly composed of silk I rather than silk II, while water- and methanol-annealed silk films had a higher silk II content. The silk films prepared by slow drying had a globule-like structure at the core surrounded by nano-filaments. The core region was composed of silk I and silk II, surrounded by hydrophilic nano-filaments containing random turns and {alpha}-helix secondary structures. The insoluble silk films prepared by slow drying had unique thermal, mechanical and degradative properties. Differential scanning calorimetry results revealed that silk I crystals had stable thermal properties up to 250 C, without crystallization above the T{sub g}, but degraded at lower temperatures than silk II structure. Compared with water- and methanol-annealed films the films prepared by slow drying had better mechanical ductility and were more rapidly enzymatically degraded, reflecting the differences in secondary structure achieved via differences in post processing of the cast silk films. Importantly, the silk I structure, a key intermediate secondary structure for the formation of mechanically robust natural silk fibers, was successfully generated by the present approach of very slow drying, mimicking the natural process. The results also point to a new mode of generating new types of silk biomaterials with enhanced mechanical properties and increased degradation rates, while maintaining water insolubility, along with a low {beta}-sheet content.

  14. Contact angles of wetting and water stability of soil structure

    Science.gov (United States)

    Kholodov, V. A.; Yaroslavtseva, N. V.; Yashin, M. A.; Frid, A. S.; Lazarev, V. I.; Tyugai, Z. N.; Milanovskiy, E. Yu.

    2015-06-01

    From the soddy-podzolic soils and typical chernozems of different texture and land use, dry 3-1 mm aggregates were isolated and sieved in water. As a result, water-stable aggregates and water-unstable particles composing dry 3-1 mm aggregates were obtained. These preparations were ground, and contact angles of wetting were determined by the static sessile drop method. The angles varied from 11° to 85°. In most cases, the values of the angles for the water-stable aggregates significantly exceeded those for the water-unstable components. In terms of carbon content in structural units, there was no correlation between these parameters. When analyzing the soil varieties separately, the significant positive correlation between the carbon content and contact angle of aggregates was revealed only for the loamy-clayey typical chernozem. Based on the multivariate analysis of variance, the value of contact wetting angle was shown to be determined by the structural units belonging to water-stable or water-unstable components of macroaggregates and by the land use type. In addition, along with these parameters, the texture has an indirect effect.

  15. Structure of liquid water at high pressures and temperatures

    CERN Document Server

    Eggert, J H; Loubeyre, P

    2002-01-01

    We report quantitatively accurate structure-factor and radial-distribution-function measurements of liquid water in a diamond-anvil cell (DAC) using x-ray diffraction. During the analysis of our diffraction data, we found it possible (and necessary) to also determine the density. Thus, we believe we present the first-ever diffraction-based determination of a liquid structure factor and equation of state in a DAC experiment.

  16. Effect of Magnesium Oxide Nanoparticles on Water Glass Structure

    Directory of Open Access Journals (Sweden)

    Bobrowski A.

    2012-09-01

    Full Text Available An attempt has been made to determine the effect of an addition of colloidal suspensions of the nanoparticles of magnesium oxide on the structure of water glass, which is a binder for moulding and core sands. Nanoparticles of magnesium oxide MgO in propanol and ethanol were introduced in the same mass content (5wt.% and structural changes were determined by measurement of the FT-IR absorption spectra.

  17. Freely floating structures trapping time-harmonic water waves (revisited)

    OpenAIRE

    Kuznetsov, Nikolay; Motygin, Oleg

    2014-01-01

    We study the coupled small-amplitude motion of the mechanical system consisting of infinitely deep water and a structure immersed in it. The former is bounded above by a free surface, whereas the latter is formed by an arbitrary finite number of surface-piercing bodies floating freely. The mathematical model of time-harmonic motion is a spectral problem in which the frequency of oscillations serves as the spectral parameter. It is proved that there exist axisymmetric structures consisting of ...

  18. Structure of human insulin monomer in water/acetonitrile solution

    Energy Technology Data Exchange (ETDEWEB)

    Bocian, Wojciech; Sitkowski, Jerzy; Bednarek, Elzbieta [National Medicines Institute (Poland); Tarnowska, Anna; Kawecki, Robert [Institute of Organic Chemistry Polish Academy of Sciences (Poland); Kozerski, Lech [National Medicines Institute (Poland)], E-mail: lkoz@icho.edu.pl

    2008-01-15

    Here we present evidence that in water/acetonitrile solvent detailed structural and dynamic information can be obtained for important proteins that are naturally present as oligomers under native conditions. An NMR-derived human insulin monomer structure in H{sub 2}O/CD{sub 3}CN, 65/35 vol%, pH 3.6 is presented and compared with the available X-ray structure of a monomer that forms part of a hexamer (Acta Crystallogr. 2003 Sec. D59, 474) and with NMR structures in water and organic cosolvent. Detailed analysis using PFGSE NMR, temperature-dependent NMR, dilution experiments and CSI proves that the structure is monomeric in the concentration and temperature ranges 0.1-3 mM and 10-30 deg. C, respectively. The presence of long-range interstrand NOEs, as found in the crystal structure of the monomer, provides the evidence for conservation of the tertiary structure. Starting from structures calculated by the program CYANA, two different molecular dynamics simulated annealing refinement protocols were applied, either using the program AMBER in vacuum (AMBER{sub V}C), or including a generalized Born solvent model (AMBER{sub G}B)

  19. Structure of human insulin monomer in water/acetonitrile solution

    International Nuclear Information System (INIS)

    Bocian, Wojciech; Sitkowski, Jerzy; Bednarek, Elzbieta; Tarnowska, Anna; Kawecki, Robert; Kozerski, Lech

    2008-01-01

    Here we present evidence that in water/acetonitrile solvent detailed structural and dynamic information can be obtained for important proteins that are naturally present as oligomers under native conditions. An NMR-derived human insulin monomer structure in H 2 O/CD 3 CN, 65/35 vol%, pH 3.6 is presented and compared with the available X-ray structure of a monomer that forms part of a hexamer (Acta Crystallogr. 2003 Sec. D59, 474) and with NMR structures in water and organic cosolvent. Detailed analysis using PFGSE NMR, temperature-dependent NMR, dilution experiments and CSI proves that the structure is monomeric in the concentration and temperature ranges 0.1-3 mM and 10-30 deg. C, respectively. The presence of long-range interstrand NOEs, as found in the crystal structure of the monomer, provides the evidence for conservation of the tertiary structure. Starting from structures calculated by the program CYANA, two different molecular dynamics simulated annealing refinement protocols were applied, either using the program AMBER in vacuum (AMBER V C), or including a generalized Born solvent model (AMBER G B)

  20. Skin lipid structure controls water permeability in snake molts.

    Science.gov (United States)

    Torri, Cristian; Mangoni, Alfonso; Teta, Roberta; Fattorusso, Ernesto; Alibardi, Lorenzo; Fermani, Simona; Bonacini, Irene; Gazzano, Massimo; Burghammer, Manfred; Fabbri, Daniele; Falini, Giuseppe

    2014-01-01

    The role of lipids in controlling water exchange is fundamentally a matter of molecular organization. In the present study we have observed that in snake molt the water permeability drastically varies among species living in different climates and habitats. The analysis of molts from four snake species: tiger snake, Notechis scutatus, gabon viper, Bitis gabonica, rattle snake, Crotalus atrox, and grass snake, Natrix natrix, revealed correlations between the molecular composition and the structural organization of the lipid-rich mesos layer with control in water exchange as a function of temperature. It was discovered, merging data from micro-diffraction and micro-spectroscopy with those from thermal, NMR and chromatographic analyses, that this control is generated from a sophisticated structural organization that changes size and phase distribution of crystalline domains of specific lipid molecules as a function of temperature. Thus, the results of this research on four snake species suggest that in snake skins different structured lipid layers have evolved and adapted to different climates. Moreover, these lipid structures can protect, "safety", the snakes from water lost even at temperatures higher than those of their usual habitat. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. A structured ecosystem-scale approach to marine water quality ...

    African Journals Online (AJOL)

    These, in turn, created the need for holistic and integrated frameworks within which to design and implement environmental management programmes. A structured ecosystem-scale approach for the design and implementation of marine water quality management programmes developed by the CSIR (South Africa) in ...

  2. Tempered Water Lower Port Connector Structural Analysis Verification

    International Nuclear Information System (INIS)

    CREA, B.A.

    2000-01-01

    Structural analysis of the lower port connection of the Tempered Water System of the Cold Vacuum Drying Facility was performed. Subsequent detailed design changes to enhance operability resulted in the need to re-evaluate the bases of the original analysis to verify its continued validity. This evaluation is contained in Appendix A of this report. The original evaluation is contained in Appendix B

  3. Influence of ground water on soil-structure interaction

    International Nuclear Information System (INIS)

    Costantino, C.J.; Graves, H.L.

    1987-01-01

    The basic problem consists of a liner flexible structure situated at or near the surface of a soil half-space. In keeping with typical small strain seismic analyses, the soil skeleton is represented as a linear medium in which all potential nonlinearities are at most lumped together into an equivalent hysteretic damping modulus. In addition, the ground water level is located at some depth relatively close to the structure, and in a position to impact on the seismic response of the facility. In order to estimate the response of this oil-water system, the two-phased medium formulation of Biot was used to treat the response of the solids and water as two separate linear media, coupled together through soil permeability and volume effects. (orig./HP)

  4. Structure of bound water and refinement of acid metmyoglobin

    International Nuclear Information System (INIS)

    Raghaven, N.V.; Schoenborn, B.P.

    1982-06-01

    The structure of myoglobin has been determined by x-ray diffraction for the acidmet, deoxy, and the oxy forms. Neutron diffraction work, done in this laboratory, has demonstrated that hydrogen and deuterium positions can be located. In addition to the localization of H and D, neutron diffraction provides a unique method for studying the water structure because of the strong scattering ability of D 2 O. The scattering factor of deuterium is nearly twice as large as that of hydrogen, and it increases the visibility of water molecules in Fourier maps, so that in a neutron map a water molecule appears about three times as strong as in an equivalent electron-density map. (DT)

  5. Structure of the floating water bridge and water in an electric field.

    Science.gov (United States)

    Skinner, Lawrie B; Benmore, Chris J; Shyam, Badri; Weber, J K R; Parise, John B

    2012-10-09

    The floating water bridge phenomenon is a freestanding rope-shaped connection of pure liquid water, formed under the influence of a high potential difference (approximately 15 kV). Several recent spectroscopic, optical, and neutron scattering studies have suggested that the origin of the bridge is associated with the formation of anisotropic chains of water molecules in the liquid. In this work, high energy X-ray diffraction experiments have been performed on a series of floating water bridges as a function of applied voltage, bridge length, and position within the bridge. The two-dimensional X-ray scattering data showed no direction-dependence, indicating that the bulk water molecules do not exhibit any significant preferred orientation along the electric field. The only structural changes observed were those due to heating, and these effects were found to be the same as for bulk water. These X-ray scattering measurements are supported by molecular dynamics (MD) simulations which were performed under electric fields of 10(6) V/m and 10(9) V/m. Directional structure factor calculations were made from these simulations parallel and perpendicular to the E-field. The 10(6) V/m model showed no significant directional-dependence (anisotropy) in the structure factors. The 10(9) V/m model however, contained molecules aligned by the E-field, and had significant structural anisotropy.

  6. Modelling soil-water dynamics in the rootzone of structured and water-repellent soils

    Science.gov (United States)

    Brown, Hamish; Carrick, Sam; Müller, Karin; Thomas, Steve; Sharp, Joanna; Cichota, Rogerio; Holzworth, Dean; Clothier, Brent

    2018-04-01

    In modelling the hydrology of Earth's critical zone, there are two major challenges. The first is to understand and model the processes of infiltration, runoff, redistribution and root-water uptake in structured soils that exhibit preferential flows through macropore networks. The other challenge is to parametrise and model the impact of ephemeral hydrophobicity of water-repellent soils. Here we have developed a soil-water model, which is based on physical principles, yet possesses simple functionality to enable easier parameterisation, so as to predict soil-water dynamics in structured soils displaying time-varying degrees of hydrophobicity. Our model, WEIRDO (Water Evapotranspiration Infiltration Redistribution Drainage runOff), has been developed in the APSIM Next Generation platform (Agricultural Production Systems sIMulation). The model operates on an hourly time-step. The repository for this open-source code is https://github.com/APSIMInitiative/ApsimX. We have carried out sensitivity tests to show how WEIRDO predicts infiltration, drainage, redistribution, transpiration and soil-water evaporation for three distinctly different soil textures displaying differing hydraulic properties. These three soils were drawn from the UNSODA (Unsaturated SOil hydraulic Database) soils database of the United States Department of Agriculture (USDA). We show how preferential flow process and hydrophobicity determine the spatio-temporal pattern of soil-water dynamics. Finally, we have validated WEIRDO by comparing its predictions against three years of soil-water content measurements made under an irrigated alfalfa (Medicago sativa L.) trial. The results provide validation of the model's ability to simulate soil-water dynamics in structured soils.

  7. The real performance of radioactive lightning arrester

    International Nuclear Information System (INIS)

    Leite, D.M.

    1985-01-01

    The study of the performance of radioactive lightning arrester comparing to the performance of conventional one are presented. Measurements of currents between lightning arrester and an energyzed plate with wind simulation were done for radioactive and conventional lightning arresters, separately. The attraction range of radioactive and conventional lightning arresters using atmospheric pulses produced by a generator of 3MV were verified, separately and simultaneously. The influence of ionization produced by radioactive lightning arrester on critical disruptive tension of a spark plate, testing two lightning arresters for differents nominal attraction distances with applications of atmospheric pulses (positive and negative polarity) and tensions of 60 Hz was verified. The radiation emitted by a radioactive lightning had used in a building was retired and handled without special carefullness by a personnel without worthy of credence to evaluate the hazard in handling radioactive lightning arrester was measured. Critical disruptive tensions of radioactive and conventional lightning arrester using a suspensed electrode and external pulse generator of 6MV was measured. The effect of attraction of a radioactive and conventional lightning arresters disposed symmetrically regarding the same suspensed electrode was verified simultaneously. Seven cases on faults of radioactive lightning arrester in external areas are present. (M.C.K.) [pt

  8. The structure of liquid water; La structure de l'eau liquide

    Energy Technology Data Exchange (ETDEWEB)

    Marin, B [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1969-07-01

    We have tried to expose a bibliography so complete as possible on structure of liquid water. One synthesis of the different models of water structure is presently impossible, so, we have exposed the main properties of water. We have pointed out the new hypotheses on the electronic structure of water molecule and on the theory of hydrogen bond. After that, we have put together the studies of structure by spectroscopy and given the main deductions of some workers on this subject. We have also exposed the characteristics of processes: relaxation and dielectric constant, influence of temperature on structure. At last, we have considered briefly the partition and thermodynamic functions established from the various models proposed. (author) [French] Nous nous sommes proposes d'ecrire une bibliographie aussi complete que possible sur la structure de l'eau liquide. Apres avoir rappele les differentes tentatives d'etablissement de modele de structure, et s'etre rendu compte qu'une synthese s'averait impossible, il nous est apparu souhaitable d'exposer les principales proprietes de l'eau. C'est ainsi que nous avons donne les hypotheses les plus recentes sur la structure electronique de la molecule d'eau ainsi que celles concernant la theorie de la liaison hydrogene. Puis nous avons rassemble les etudes de structure par spectroscopie et fourni les deductions auxquelles les divers auteurs sont arrives. Nous avons egalement expose les caracteristiques des processus tels que: relaxation et constante dielectrique, l'influence de la temperature sur la structure et enfin nous avons donne brievement les fonctions de partition et les grandeurs thermodynamiques etablies a partir des divers modeles proposes. (auteur)

  9. Structural Optimization of Triboelectric Nanogenerator for Harvesting Water Wave Energy.

    Science.gov (United States)

    Jiang, Tao; Zhang, Li Min; Chen, Xiangyu; Han, Chang Bao; Tang, Wei; Zhang, Chi; Xu, Liang; Wang, Zhong Lin

    2015-12-22

    Ocean waves are one of the most abundant energy sources on earth, but harvesting such energy is rather challenging due to various limitations of current technologies. Recently, networks formed by triboelectric nanogenerator (TENG) have been proposed as a promising technology for harvesting water wave energy. In this work, a basic unit for the TENG network was studied and optimized, which has a box structure composed of walls made of TENG composed of a wavy-structured Cu-Kapton-Cu film and two FEP thin films, with a metal ball enclosed inside. By combination of the theoretical calculations and experimental studies, the output performances of the TENG unit were investigated for various structural parameters, such as the size, mass, or number of the metal balls. From the viewpoint of theory, the output characteristics of TENG during its collision with the ball were numerically calculated by the finite element method and interpolation method, and there exists an optimum ball size or mass to reach maximized output power and electric energy. Moreover, the theoretical results were well verified by the experimental tests. The present work could provide guidance for structural optimization of wavy-structured TENGs for effectively harvesting water wave energy toward the dream of large-scale blue energy.

  10. Structural conceptual models of water-conducting features at Aespoe

    International Nuclear Information System (INIS)

    Bossart, P.; Mazurek, M.; Hermansson, Jan

    1998-01-01

    Within the framework of the Fracture Classification and Characterization Project (FCC), water conducting features (WCF) in the Aespoe tunnel system and on the surface of Aespoe Island are being characterized over a range of scales. The larger-scale hierarchies of WCF are mostly constituted of fault arrays, i.e. brittle structures that accommodated episodes of shear strain. The smaller-scale WCF (contained within blocks 1 m. Structural evidence indicates that the fractures within the TRUE-1 block constitute an interconnected system with a pronounced anisotropy

  11. An engineering interpretation of pop-in arrest and tearing arrest in terms of static crack arrest, Ksub(Ia)

    International Nuclear Information System (INIS)

    Witt, F.J.

    1983-01-01

    When fracture toughness specimens are tested under displacement controlled conditions, they are often observed to exhibit unstable cleavage fracture followed by arrest of the cleavage mode wherein a significant load remains on the specimen (pop-in arrest). This behavior carries over into the ductile tearing regime wherein tearing may occur rapidly identified by load reduction and then proceeds at a discernible less rate (tearing arrest). Both these behaviors represent an initiation condition followed by an arrest condition. In this paper it is demonstrated that from either of the arrest conditions an arrest value may be determined which, for available experimental data, is shown to be an engineering estimate for the static crack arrest toughness, Ksub(Ia). A data analysis procedure is outlined and Ksub(Ic) and Ksub(Ia) estimates from sixty-eight 1/2, 1 and 2 in. thick compact specimens from two steels (A533 Grade B Class 1 and AISI 1018) tested between -40 deg F and 200 deg F are summarized. The crack arrest estimates are seen to compare favorably with Ksub(Ia) results obtained by other investigators using 2 in. thick specimens. Also it is demonstrated that when failure is by fully ductile tearing, the crack arrest toughness is at least equal to the estimate for Ksub(Ic) for the specimen. (author)

  12. Induced activity in accelerator structures, air and water

    CERN Document Server

    Stevenson, Graham Roger

    2001-01-01

    A summary is given of several 'rules of thumb' which can be used to predict the formation and decay of radionuclides in the structure of accelerators together with the dose rates from the induced radioactivity. Models are also given for the activation of gases (air of the accelerator vault) and liquids (in particular cooling water), together with their transport front the activation region to the release point. (18 refs).

  13. Dropwise chains as the elements of water fog spatial structure

    International Nuclear Information System (INIS)

    Shavlov, A.V.; Sokolov, I.V.; Romanyuk, S.N.; Dzhumandzhi, V.A.

    2013-01-01

    Video images of water fog drops were acquired under standard atmospheric conditions with weak turbulence of the environment. Pair correlation functions of the drops were performed and traces of the spatial arrangement of the drops inside the fog determined. The fog structure carriers are the drop chains with a fixed interdroplet distance. The possible influence of the drop chains on the shear viscosity and fog surface tension has been analysed.

  14. Soil-structure interaction Vol.3. Influence of ground water

    Energy Technology Data Exchange (ETDEWEB)

    Costantino, C J

    1986-04-01

    This study has been performed for the Nuclear Regulatory Commission (NRC) by the Structural Analysis Division of Brookhaven National Laboratory (BNL). The study was conducted during the fiscal year 1965 on the program entitled 'Benchmarking of Structural Engineering Problems' sponsored by NRC. The program considered three separate but complementary problems, each associated with the soil-structure interaction (551) phase of the seismic response analysis of nuclear plant facilities. The reports, all entitled Soil-Structure Interaction, are presented in three separate volumes, namely: Vol. 1 Influence of Layering by AJ Philippacopoulos, Vol. 2 Influence of Lift-Off by C.A. Miller, Vol. 3 Influence of Ground Water by C.J. Costantino. The two problems presented in Volumes 2 and 3 were conducted at the City University of New York (CUNY) under subcontract to BNL. This report, Volume 3 of the report, presents a summary of the first year's effort on the subject of the influence of foundation ground water on the SSI phenomenon. A finite element computer program was developed for the two-phased formulation of the combined soil-water problem. This formulation is based on the Biot dynamic equations of motion for both the solid and fluid phases of a typical soil. Frequency dependent interaction coefficients were generated for the two-dimensional plane problem of a rigid surface footing moving against a saturated linear soil. The results indicate that interaction coefficients are significantly modified as compared to the comparable values for a dry soil, particularly for the rocking mode of response. Calculations were made to study the impact of the modified interaction coefficients on the response of a typical nuclear reactor building. The amplification factors for a stick model placed atop a dry and saturated soil were computed. It was found that pore water caused the rocking response to decrease and translational response to increase over the frequency range of interest, as

  15. Induced activity in accelerator structures, air and water

    International Nuclear Information System (INIS)

    Stevenson, G.R.

    2001-01-01

    A summary is given of several 'rules of thumb' which can be used to predict the formation and decay of radionuclides in the structure of accelerators together with the dose rates from the induced radioactivity. Models are also given for the activation of gases (air of the accelerator vault) and liquids (in particular cooling water), together with their transport from the activation region to the release point. (author)

  16. Thermomechanical finite element analysis of hot water boiler structure

    Directory of Open Access Journals (Sweden)

    Živković Dragoljub S.

    2012-01-01

    Full Text Available The paper presents an application of the Finite Elements Method for stress and strain analysis of the hot water boiler structure. The aim of the research was to investigate the influence of the boiler scale on the thermal stresses and strains of the structure of hot water boilers. Results show that maximum thermal stresses appear in the zone of the pipe carrying wall of the first reversing chamber. This indicates that the most critical part of the boiler are weld spots of the smoke pipes and pipe carrying plate, which in the case of significant scale deposits can lead to cracks in the welds and water leakage from the boiler. The nonlinear effects were taken into account by defining the bilinear isotropic hardening model for all boiler elements. Temperature dependency was defined for all relevant material properties, i. e. isotropic coefficient of thermal expansion, Young’s modulus, and isotropic thermal conductivity. The verification of the FEA model was performed by comparing the measured deformations of the hot water boiler with the simulation results. As a reference object, a Viessmann - Vitomax 200 HW boiler was used, with the installed power of 18.2 MW. CAD modeling was done within the Autodesk Inventor, and stress and strain analysis was performed in the ANSYS Software.

  17. Structure of Mesozooplankton Communities in the Coastal Waters of Morocco

    Science.gov (United States)

    Lidvanov, V. V.; Grabko, O. G.; Kukuev, E. I.; Korolkova, T. G.

    2018-03-01

    Mero- and holoplanktonic organisms from 23 large taxa have been detected in the coastal waters of Morocco. Seven Cladocera species and 164 Copepoda species were identified. Copepod fauna mostly consisted of oceanic epipelagic widely tropical species, but the constant species group (frequency of occurrence over 50%) included neritic and neritic-oceanic widely tropical species. The neritic community that formed a biotopic association with coastal upwelling waters and the distant-neritic community associated with Canary Current waters were the two major communities detected. The former community was characterized by a high abundance and biomass (5700 ind./m3 and 260 mg/m3) and predominance of neritic species. The trophic structure was dominated by thin filter feeders, mixed-food consumers, and small grabbers; the species structure was dominated by Paracalanus indicus, Acartia clausi, and Oncaea curta; the indices of species diversity (3.07 bit/ind.) and evenness (0.63) were relatively low. The latter community was characterized by low abundance and biomass (1150 ind./m3 and 90 mg/m3); variable biotopic, trophic, and species structure; and higher Shannon indices (3.99 bit/ind.) and Pielou (0.75). Seasonal variation of the abundance of organisms was not detected in the communities. Anomalous mesozooplankton states were observed in summer 1998 and winter 1998-1999.

  18. Gas hydrate inhibition by perturbation of liquid water structure

    Science.gov (United States)

    Sa, Jeong-Hoon; Kwak, Gye-Hoon; Han, Kunwoo; Ahn, Docheon; Lee, Kun-Hong

    2015-06-01

    Natural gas hydrates are icy crystalline materials that contain hydrocarbons, which are the primary energy source for this civilization. The abundance of naturally occurring gas hydrates leads to a growing interest in exploitation. Despite their potential as energy resources and in industrial applications, there is insufficient understanding of hydrate kinetics, which hinders the utilization of these invaluable resources. Perturbation of liquid water structure by solutes has been proposed to be a key process in hydrate inhibition, but this hypothesis remains unproven. Here, we report the direct observation of the perturbation of the liquid water structure induced by amino acids using polarized Raman spectroscopy, and its influence on gas hydrate nucleation and growth kinetics. Amino acids with hydrophilic and/or electrically charged side chains disrupted the water structure and thus provided effective hydrate inhibition. The strong correlation between the extent of perturbation by amino acids and their inhibition performance constitutes convincing evidence for the perturbation inhibition mechanism. The present findings bring the practical applications of gas hydrates significantly closer, and provide a new perspective on the freezing and melting phenomena of naturally occurring gas hydrates.

  19. Arresting Strategy Based on Dynamic Criminal Networks Changing over Time

    Directory of Open Access Journals (Sweden)

    Junqing Yuan

    2013-01-01

    Full Text Available We investigate a sequence of dynamic criminal networks on a time series based on the dynamic network analysis (DNA. According to the change of networks’ structure, networks’ variation trend is analyzed to forecast its future structure. Finally, an optimal arresting time and priority list are designed based on our analysis. Better results can be expected than that based on social network analysis (SNA.

  20. Structural arrest in an ideal gas

    NARCIS (Netherlands)

    Ketel, W. van; Das, C.; Frenkel, D.

    2005-01-01

    We report a molecular dynamics study of a simple model system that has the static properties of an ideal gas, yet exhibits nontrivial "glassy" dynamics behavior at high densities. The constituent molecules of this system are constructs of three infinitely thin hard rods of length L, rigidly joined

  1. Influence of ground water on soil-structure interaction

    International Nuclear Information System (INIS)

    Costantino, C.J.; Lung, R.H.; Graves, H.L.

    1987-01-01

    The study of structural response to seismic inputs has been extensively studied and, particularly with the advent of the growth of digital computer capability, has lead to the development of numerical methods of analysis which are used as standard tools for the design of structures. One aspect of the soil-structure interaction (SSI) process which has not been developed to the same degree of sophistication is the impact of ground water (or pure water) on the response of the soil-structure system. There are very good reasons for his state of affairs, however, not the least of which is the difficulty of incorporating the true constitutive behavior of saturated soils into the analysis. At the large strain end of the spectrum, the engineer is concerned with the potential development of failure conditions under the structure, and is typically interested in the onset of liquefaction conditions. The current state of the art in this area is to a great extent based on empirical methods of analysis which were developed from investigations of limited failure data from specific sites around the world. Since it is known that analytic solutions are available for only the simplest of configurations, a numerical finite element solution process was developed. Again, in keeping with typical SSI analyses, in order to make the finite element approach yield resonable results, a comparable transmitting boundary formulation was included in the development. The purpose of the transmitting boundary is, of course, to allow for the treatment of extended soil/water half-space problems. For the calculations presented herein, a simple one dimensional transmitting boundary model was developed and utilized

  2. Dynamic photoelastic investigation of crack arrest

    International Nuclear Information System (INIS)

    Irwin, G.R.; Dally, J.W.; Kobayashi, T.; Fourney, W.L.

    1977-01-01

    Crack arrest and crack arrest toughness are of great interest, particularly for studies pertaining to safety of nuclear reactor pressure vessels. Investigations are needed in which the instantaneous values of stress intensity factor (K) can be observed during crack propagation and arrest. Such observations are possible if the test specimens are made from plates of a transparent photoelastic sensitive material. Values of K as a function of crack speed are shown for Homalite 100 and various epoxy blends. 9 figures

  3. Ventilation and gas exchange management after cardiac arrest.

    Science.gov (United States)

    Sutherasan, Yuda; Raimondo, Pasquale; Pelosi, Paolo

    2015-12-01

    For several decades, physicians had integrated several interventions aiming to improve the outcomes in post-cardiac arrest patients. However, the mortality rate after cardiac arrest is still as high as 50%. Post-cardiac arrest syndrome is associated with high morbidity and mortality due to not only poor neurological outcome and cardiovascular failure but also respiratory dysfunction. To minimize ventilator-associated lung injury, protective mechanical ventilation by using low tidal volume ventilation and driving pressure may decrease pulmonary complications and improve survival. Low level of positive end-expiratory pressure (PEEP) can be initiated and titrated with careful cardiac output and respiratory mechanics monitoring. Furthermore, optimizing gas exchange by avoiding hypoxia and hyperoxia as well as maintaining normocarbia may improve neurological and survival outcome. Early multidisciplinary cardiac rehabilitation intervention is recommended. Minimally invasive monitoring techniques, that is, echocardiography, transpulmonary thermodilution method measuring extravascular lung water, as well as transcranial Doppler ultrasound, might be useful to improve appropriate management of post-cardiac arrest patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Solvation structures of lithium halides in methanol–water mixtures

    International Nuclear Information System (INIS)

    Sarkar, Atanu; Dixit, Mayank Kumar; Tembe, B.L.

    2015-01-01

    Highlights: • Potentials of mean force for Li + -halides are calculated in methanol–water mixtures. • Stable CIP for x methanol = 1.0 becomes unstable at and below x methanol = 0.75. • The Li + ion is preferentially solvated by methanol molecules. • The halide ions are preferentially solvated by water molecules. - Abstract: The potentials of mean force (PMFs) for the ion pairs, Li + −Cl − , Li + −Br − and Li + −I − have been calculated in five methanol–water compositions. The results obtained are verified by trailing the trajectories and calculating the ion pair distance residence times. Local structures around the ions are studied using the radial distribution functions, density profiles, orientational correlation functions, running coordination numbers and excess coordination numbers. The major change in PMF is observed as the methanol mole fraction (x methanol ) is changed from 1.0 to 0.75. The stable contact ion pair occurring for x methanol = 1.0 becomes unstable at and below x methanol = 0.75. The preferential solvation data show that the halide ions are always preferentially solvated by water molecules. Although the lithium ion is preferentially solvated by methanol molecules, there is significant affinity towards water molecules as well

  5. Triple oxygen isotope systematics of structurally bonded water in gypsum

    Science.gov (United States)

    Herwartz, Daniel; Surma, Jakub; Voigt, Claudia; Assonov, Sergey; Staubwasser, Michael

    2017-07-01

    The triple oxygen isotopic composition of gypsum mother water (gmw) is recorded in structurally bonded water in gypsum (gsbw). Respective fractionation factors have been determined experimentally for 18O/16O and 17O/16O. By taking previous experiments into account we suggest using 18αgsbw-gmw = 1.0037; 17αgsbw-gmw = 1.00195 and θgsbw-gmw = 0.5285 as fractionation factors in triple oxygen isotope space. Recent gypsum was sampled from a series of 10 ponds located in the Salar de Llamara in the Atacama Desert, Chile. Total dissolved solids (TDS) in these ponds show a gradual increase from 23 g/l to 182 g/l that is accompanied by an increase in pond water 18O/16O. Gsbw falls on a parallel curve to the ambient water from the saline ponds. The offset is mainly due to the equilibrium fractionation between gsbw and gmw. However, gsbw represents a time integrated signal biased towards times of strong evaporation, hence the estimated gmw comprises elevated 18O/16O compositions when compared to pond water samples taken on site. Gypsum precipitation is associated with algae mats in the ponds with lower salinity. No evidence for respective vital effects on the triple oxygen isotopic composition of gypsum hydration water is observed, nor are such effects expected. In principle, the array of δ18Ogsbw vs. 17Oexcess can be used to: (1) provide information on the degree of evaporation during gypsum formation; (2) estimate pristine meteoric water compositions; and (3) estimate local relative humidity which is the controlling parameter of the slope of the array for simple hydrological situations. In our case study, local mining activities may have decreased deep groundwater recharge, causing a recent change of the local hydrology.

  6. Simulated Cardiopulmonary Arrests in a Hospital Setting.

    Science.gov (United States)

    Mishkin, Barbara H.; And Others

    1982-01-01

    Describes a simulated interdisciplinary role rehearsal for cardiopulmonary arrest to prepare nurses to function effectively. Includes needs analysis, program components, and responses of program participants. (Author)

  7. Water linked 3D coordination polymers: Syntheses, structures and applications

    Science.gov (United States)

    Singh, Suryabhan; Bhim, Anupam

    2016-12-01

    Three new coordination polymers (CPs) based on Cd and Pb, [Cd(OBA)(μ-H2O)(H2O)]n1, [Pb(OBA)(μ-H2O)]n2 [where OBA=4,4'-Oxybis(benzoate)] and [Pb(SDBA)(H2O)]n.1/4DMF 3 (SDBA=4,4'-Sulfonyldibenzoate), have been synthesized and characterized. The single crystal structural studies reveal that CPs 1 and 2 have three dimensional structure. A water molecule bridges two metal centres which appears to the responsible for the dimensionality increase from 2D to 3D. Compound 3 has a supramolecular 3D structure involving water molecule and hydrogen bonds. A structural transformation is observed when 3 was heated at 100 °C or kept in methanol, forming [Pb(SDBA)]n4. Compound 4 is used as supporting matrix for palladium nanoparticles, PdNPs@4. The PdNPs@4 exhibits good catalytic activity toward the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of NaBH4 at room temperature. Luminescence studies revealed that all CPs could be an effective sensor for nitroaromatic explosives.

  8. Urban water infrastructure asset management - a structured approach in four water utilities.

    Science.gov (United States)

    Cardoso, M A; Silva, M Santos; Coelho, S T; Almeida, M C; Covas, D I C

    2012-01-01

    Water services are a strategic sector of large social and economic relevance. It is therefore essential that they are managed rationally and efficiently. Advanced water supply and wastewater infrastructure asset management (IAM) is key in achieving adequate levels of service in the future, particularly with regard to reliable and high quality drinking water supply, prevention of urban flooding, efficient use of natural resources and prevention of pollution. This paper presents a methodology for supporting the development of urban water IAM, developed during the AWARE-P project as well as an appraisal of its implementation in four water utilities. Both water supply and wastewater systems were considered. Due to the different contexts and features of the utilities, the main concerns vary from case to case; some problems essentially are related to performance, others to risk. Cost is a common deciding factor. The paper describes the procedure applied, focusing on the diversity of drivers, constraints, benefits and outcomes. It also points out the main challenges and the results obtained through the implementation of a structured procedure for supporting urban water IAM.

  9. Arrested of coalescence of emulsion droplets of arbitrary size

    Science.gov (United States)

    Mbanga, Badel L.; Burke, Christopher; Blair, Donald W.; Atherton, Timothy J.

    2013-03-01

    With applications ranging from food products to cosmetics via targeted drug delivery systems, structured anisotropic colloids provide an efficient way to control the structure, properties and functions of emulsions. When two fluid emulsion droplets are brought in contact, a reduction of the interfacial tension drives their coalescence into a larger droplet of the same total volume and reduced exposed area. This coalescence can be partially or totally hindered by the presence of nano or micron-size particles that coat the interface as in Pickering emulsions. We investigate numerically the dependance of the mechanical stability of these arrested shapes on the particles size, their shape anisotropy, their polydispersity, their interaction with the solvent, and the particle-particle interactions. We discuss structural shape changes that can be induced by tuning the particles interactions after arrest occurs, and provide design parameters for the relevant experiments.

  10. Coplanar capacitance sensors for detecting water intrusion in composite structures

    International Nuclear Information System (INIS)

    Nassr, Amr A; El-Dakhakhni, Wael W; Ahmed, Wael H

    2008-01-01

    Composite materials are becoming more affordable and widely used for retrofitting, rehabilitating and repairing reinforced concrete structures designed and constructed under older specifications. However, the mechanical properties and long-term durability of composite materials may degrade severely in the presence of water intrusion. This study presents a new non-destructive evaluation (NDE) technique for detecting the water intrusion in composite structures by evaluating the dielectric properties of different composite system constituent materials. The variation in the dielectric signatures was employed to design a coplanar capacitance sensor with high sensitivity to detect such defects. An analytical model was used to study the effect of the sensor geometry on the output signal and to optimize sensor design. A finite element model was developed to validate analytical results and to evaluate other sensor design-related parameters. Experimental testing of a concrete specimen wrapped with composite laminate and containing a series of pre-induced water intrusion defects was conducted in order to validate the concept of the new technique. Experimental data showed excellent agreement with the finite element model predictions and confirmed sensor performance

  11. Investigation of structural responses of breakwaters for green water based on fluid-structure interaction analysis

    Directory of Open Access Journals (Sweden)

    Chi-Seung Lee

    2012-06-01

    Full Text Available In the present study, the structural response of breakwaters installed on container carriers against green water impact loads was numerically investigated on the basis of the fluid-structure interaction analysis. A series of numerical studies is carried out to induce breakwater collapse under such conditions, whereby a widely accepted fluid-structure interaction analysis technique is adopted to realistically consider the phenomenon of green water impact loads. In addition, the structural behaviour of these breakwaters under green water impact loads is investigated simultaneously throughout the transient analysis. A verification study of the numerical results is performed using data from actual collapse incidents of breakwaters on container carriers. On the basis of the results of a series of numerical analyses, the pressure distribution of green water was accurately predicted with respect to wave mass and velocity. It is expected that the proposed analytical methodology and predicted pressure distribution could be used as a practical guideline for the design of breakwaters on container carriers.

  12. Carbamazepine induces mitotic arrest in mammalian Vero cells

    International Nuclear Information System (INIS)

    Perez Martin, J.M.; Fernandez Freire, P.; Labrador, V.; Hazen, M.J.

    2008-01-01

    We reported recently that the anticonvulsant drug carbamazepine, at supratherapeutic concentrations, exerts antiproliferative effects in mammalian Vero cells, but the underlying mechanism has not been elucidated. This motivates us to examine rigorously whether growth arrest was associated with structural changes in cellular organization during mitosis. In the present work, we found that exposure of the cells to carbamazepine led to an increase in mitotic index, mainly due to the sustained block at the metaphase/anaphase boundary, with the consequent inhibition of cell proliferation. Indirect immunofluorescence, using antibodies directed against spindle apparatus proteins, revealed that mitotic arrest was associated with formation of monopolar spindles, caused by impairment of centrosome separation. The final consequence of the spindle defects induced by carbamazepine, depended on the duration of cell cycle arrest. Following the time course of accumulation of metaphase and apoptotic cells during carbamazepine treatments, we observed a causative relationship between mitotic arrest and induction of cell death. Conversely, cells released from the block of metaphase by removal of the drug, continued to progress through mitosis and resume normal proliferation. Our results show that carbamazepine shares a common antiproliferative mechanism with spindle-targeted drugs and contribute to a better understanding of the cytostatic activity previously described in Vero cells. Additional studies are in progress to extend these initial findings that define a novel mode of action of carbamazepine in cultured mammalian cells

  13. Carbamazepine induces mitotic arrest in mammalian Vero cells

    Energy Technology Data Exchange (ETDEWEB)

    Perez Martin, J.M.; Fernandez Freire, P.; Labrador, V. [Departamento de Biologia, Facultad de Ciencias, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Hazen, M.J. [Departamento de Biologia, Facultad de Ciencias, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain)], E-mail: mariajose.hazen@uam.es

    2008-01-01

    We reported recently that the anticonvulsant drug carbamazepine, at supratherapeutic concentrations, exerts antiproliferative effects in mammalian Vero cells, but the underlying mechanism has not been elucidated. This motivates us to examine rigorously whether growth arrest was associated with structural changes in cellular organization during mitosis. In the present work, we found that exposure of the cells to carbamazepine led to an increase in mitotic index, mainly due to the sustained block at the metaphase/anaphase boundary, with the consequent inhibition of cell proliferation. Indirect immunofluorescence, using antibodies directed against spindle apparatus proteins, revealed that mitotic arrest was associated with formation of monopolar spindles, caused by impairment of centrosome separation. The final consequence of the spindle defects induced by carbamazepine, depended on the duration of cell cycle arrest. Following the time course of accumulation of metaphase and apoptotic cells during carbamazepine treatments, we observed a causative relationship between mitotic arrest and induction of cell death. Conversely, cells released from the block of metaphase by removal of the drug, continued to progress through mitosis and resume normal proliferation. Our results show that carbamazepine shares a common antiproliferative mechanism with spindle-targeted drugs and contribute to a better understanding of the cytostatic activity previously described in Vero cells. Additional studies are in progress to extend these initial findings that define a novel mode of action of carbamazepine in cultured mammalian cells.

  14. Water linked 3D coordination polymers: Syntheses, structures and applications

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Suryabhan, E-mail: sbs.bhu@gmail.com; Bhim, Anupam

    2016-12-15

    Three new coordination polymers (CPs) based on Cd and Pb, [Cd(OBA)(μ-H{sub 2}O)(H{sub 2}O)]{sub n}1, [Pb(OBA)(μ-H{sub 2}O)]{sub n}2 [where OBA=4,4’-Oxybis(benzoate)] and [Pb(SDBA)(H{sub 2}O)]{sub n}.1/4DMF 3 (SDBA=4,4’-Sulfonyldibenzoate), have been synthesized and characterized. The single crystal structural studies reveal that CPs 1 and 2 have three dimensional structure. A water molecule bridges two metal centres which appears to the responsible for the dimensionality increase from 2D to 3D. Compound 3 has a supramolecular 3D structure involving water molecule and hydrogen bonds. A structural transformation is observed when 3 was heated at 100 °C or kept in methanol, forming [Pb(SDBA)]{sub n}4. Compound 4 is used as supporting matrix for palladium nanoparticles, PdNPs@4. The PdNPs@4 exhibits good catalytic activity toward the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of NaBH{sub 4} at room temperature. Luminescence studies revealed that all CPs could be an effective sensor for nitroaromatic explosives. - Graphical abstract: Three new CPs based on Cd and Pb, have been synthesized and characterized. A water molecule bridges two metal centres which appears to the responsible for the dimensionality increase from 2D to 3D. One of the CP is used as supporting matrix for palladium nanoparticles, PdNPs@4. The PdNPs@4 exhibits good catalytic activity toward the reduction of 4-nitrophenol. Luminescence studies shown that all CPs could be an effective sensor for nitroaromatic explosives. - Highlights: • Three new CPs based on Cd and Pb, have been synthesized and characterized. • A water molecule bridges two metal centres which appears to the responsible for the dimensionality increase from 2D to 3D. • One of the CP is used as supporting matrix for palladium nanoparticles, PdNPs@4. • Luminescence studies shown that all CPs could be an effective sensor for nitroaromatic explosives.

  15. Studies on melt-water-structure interaction during severe accidents

    International Nuclear Information System (INIS)

    Sehgal, B.R.; Dinh, T.N.; Okkonen, T.J.; Bui, V.A.; Nourgaliev, R.R.; Andersson, J.

    1996-10-01

    Results of a series of studies, on melt-water-structure interactions which occur during the progression of a core melt-down accident, are described. The emphasis is on the in-vessel interactions and the studies are both experimental and analytical. Since, the studies performed resulted in papers published in proceedings of the technical meetings, and in journals, copies of a set of selected papers are attached to provide details. A summary of the results obtained is provided for the reader who does not, or cannot, venture into the perusal of the attached papers. (au)

  16. Studies on melt-water-structure interaction during severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Sehgal, B.R.; Dinh, T.N.; Okkonen, T.J.; Bui, V.A.; Nourgaliev, R.R.; Andersson, J. [Royal Inst. of Technology, Div. of Nucl. Power Safety, Stockholm (Sweden)

    1996-10-01

    Results of a series of studies, on melt-water-structure interactions which occur during the progression of a core melt-down accident, are described. The emphasis is on the in-vessel interactions and the studies are both experimental and analytical. Since, the studies performed resulted in papers published in proceedings of the technical meetings, and in journals, copies of a set of selected papers are attached to provide details. A summary of the results obtained is provided for the reader who does not, or cannot, venture into the perusal of the attached papers. (au).

  17. A One-Dimensional Hydrodynamic and Water Quality Model for a Water Transfer Project with Multihydraulic Structures

    OpenAIRE

    Yujun Yi; Caihong Tang; Zhifeng Yang; Shanghong Zhang; Cheng Zhang

    2017-01-01

    The long Middle Route of the South to North Water Transfer Project is composed of complex hydraulic structures (aqueduct, tunnel, control gate, diversion, culvert, and diverted siphon), which generate complex flow patterns. It is vital to simulate the flow patterns through hydraulic structures, but it is a challenging work to protect water quality and maintain continuous water transfer. A one-dimensional hydrodynamic and water quality model was built to understand the flow and pollutant movem...

  18. Simulating liquid water for determining its structural and transport properties

    International Nuclear Information System (INIS)

    Arismendi-Arrieta, Daniel; Medina, Juan S.; Fanourgakis, George S.; Prosmiti, Rita; Delgado-Barrio, Gerardo

    2014-01-01

    Molecular dynamics simulations are carried out for calculating structural and transport properties of pure liquid water, such as radial distribution functions and self-diffusion and viscosity coefficients, respectively. We employed reparameterized versions of the ab initio water potential by Niesar, Clementi and Corongiu (NCC). In order to investigate the role of the electrostatic contribution, the partial charges of the NCC model are adjusted so that to reproduce the dipole moment values of the SPC/E, SPC/Fw and TIP4P/2005 water models. The single and collective transport coefficients are obtained by employing the Green–Kubo relations at various temperatures. Additionally, in order to overcome convergence difficulties arising from the long correlation times of the stress-tensor autocorrelation functions, a previously reported fitting scheme was employed. The present results indicate that there is a significant relationship between the dipole moment value of the model, and the calculated transport coefficients. We found that by adjusting the molecular dipole moment of the NCC to the value of the TIP4P/2005, the obtained values for the self-diffusion and viscosity coefficients are in better agreement with experiment, compared to the values obtained with the original NCC model. Even though the predictions of the present model exhibits an overall correct behavior, we conclude that further improvements are still required. In order to achieve that, a careful reparameterization of the repulsion–dispersion terms of the potential model is proposed. Also, the effect of the inclusion of many-body effects such as polarizability, should also be investigated. - Highlights: ► Transport properties of liquid water are important in bio-simulations. ► Self-diffusion coefficient, shear and bulk viscosities calculations from NVE molecular dynamics simulations. ► Their comparison with experimental data provides information on intermolecular forces, and serve to develop water

  19. The Structure of Sea Water and Gelatinous Water in the Deep Ocean

    Science.gov (United States)

    Peltzer, E. T.; Walz, P. M.; Wojciechowicz, M.; Brewer, P. G.

    2016-12-01

    Gelatinous life forms are common in the deep sea and are able to maintain a careful combination of body integrity and easy fluidity of motion over a wide range of T and P. They accomplish this in part by modifying the molecular structure of water. Both the transparent body of the organism (the mesoglea) and the structure of the immediate surrounding sea water were investigated by in situ laser Raman spectroscopy at depths from 300m to 2,800m. The structure of water is reasonably well known; the basic unit is a hydrogen bonded pentamer with defined stretching and bending modes. The spectrum of the bending band is separable into two components while the stretching band spectrum is composed of five components representing both intra- and inter-molecular vibrations. The effect of temperature on the various vibrational modes is complex. While the effect of pressure on the bending modes is small, but the effect of temperature and pressure on the stretching modes is significant and can be modeled as a van `t Hoff function. Our in situ experiments were conducted using MBARI's ROV Ventana and ROV Doc Ricketts. We collected cnidarians and ctenophores into a 6 L glass detritus sampler fitted with a metal grid plate. Once the animal was captured, we introduced argon gas through the lid of the sampler displacing the contained sea water and leaving a motionless sea water free specimen for spectroscopy. The laser beam was focused through the glass wall of the container and the focal point adjusted to be inside the gelatinous body. Our results very clearly show that:i) The gelatinous mass effectively excludes salts with zero sulfate ion being detected.ii) The water bending modes are absent from the gelatinous spectra.iii) The water stretching modes are highly modified from the typical 5 band liquid pentamer structure with only 3 vibrational modes observable. These results stand in marked contrast to the familiar household gelatin which is typically derived from bovine sources

  20. Structure and dynamics of interfacial water. Role of hydratation water in the globular proteins dynamics

    International Nuclear Information System (INIS)

    Zanotti, J.M.

    1997-01-01

    This memoir includes five chapters. In the first chapter, are given the elements of the neutrons scattering theory that is used in this study. the second chapter is devoted to a general presentation of the interaction between biological macro molecule and water. The third part is dedicated to the study of the structure and the dynamics of interfacial water in the neighbouring of model systems, the vycor and the amorphous carbon. The results presented in this part are compared with these one relative to water dynamics at the C-phycocyanin surface. This study makes the object of the fourth chapter. Then, in the fifth and last chapter are discussed the results relative to the role of hydratation on the parv-albumin dynamics for which have been combined the neutron quasi elastic incoherent scattering and the nuclear magnetic resonance of the carbon 13 solid in natural abundance

  1. Crack propagation and arrest simulation of X90 gas pipe

    International Nuclear Information System (INIS)

    Yang, Fengping; Huo, Chunyong; Luo, Jinheng; Li, He; Li, Yang

    2017-01-01

    To determine whether X90 steel pipe has enough crack arrest toughness or not, a damage model was suggested as crack arrest criterion with material parameters of plastic uniform percentage elongation and damage strain energy per volume. Fracture characteristic length which characterizes fracture zone size was suggested to be the largest mesh size on expected cracking path. Plastic uniform percentage elongation, damage strain energy per volume and fracture characteristic length of X90 were obtained by five kinds of tensile tests. Based on this criterion, a length of 24 m, Φ1219 × 16.3 mm pipe segment model with 12 MPa internal gas pressure was built and computed with fluid-structure coupling method in ABAQUS. Ideal gas state equation was used to describe lean gas behavior. Euler grid was used to mesh gas zone inside the pipe while Lagrangian shell element was used to mesh pipe. Crack propagation speed and gas decompression speed were got after computation. The result shows that, when plastic uniform percentage elongation is equal to 0.054 and damage strain energy per volume is equal to 0.64 J/mm"3, crack propagation speed is less than gas decompression speed, which means the simulated X90 gas pipe with 12 MPa internal pressure can arrest cracking itself. - Highlights: • A damage model was suggested as crack arrest criterion. • Plastic uniform elongation and damage strain energy density are material parameters. • Fracture characteristic length is suggested to be largest mesh size in cracking path. • Crack propagating simulation with coupling of pipe and gas was realized in ABAQUS. • A Chinese X90 steel pipe with 12 MPa internal pressure can arrest cracking itself.

  2. Structural characterization of the exopolysaccharides from water kefir.

    Science.gov (United States)

    Fels, Lea; Jakob, Frank; Vogel, Rudi F; Wefers, Daniel

    2018-06-01

    Water kefir is a beverage which is produced by initiating fermentation of a fruit extract/sucrose solution with insoluble kefir grains. Exopolysaccharides that are formed from sucrose play a major role in the kefir grain formation, but the exopolysaccharides in the kefir beverage and the detailed structural composition of the whole kefir grains have not been studied yet. Therefore, kefir grains and the corresponding kefir beverage were analyzed for exopolysaccharides by multiple chromatographic approaches and two-dimensional NMR spectroscopy. Furthermore, different fractionation techniques were applied to obtain further information about the exopolysaccharides. The exopolysaccharide-fraction of the investigated kefir beverage was predominantly composed of O3- and O2-branched dextrans as well as lower amounts of levans. The insoluble dextrans from the kefir grains were mostly O3-branched and contained an elevated portion of 1,3-linked glucose units compared to the soluble dextrans. The structurally different exopolysaccharides in water kefir suggest the involvement of multiple bacteria. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Influence of organobentonite structure on toluene adsorption from water solution

    Directory of Open Access Journals (Sweden)

    Nuria Vidal

    2012-12-01

    Full Text Available Due to increase water pollution by organic compound derived from hydrocarbons such as toluene, several alternative technologies for remediation of polluted water have been originated. In this work natural bentonites were modified with cetyltrimethylammonium (CTMA+ for obtaining organophilic bentonites. The obtained CTMA-bentonites would be suitable for use as adsorbents of toluene present in water. The influence of structural characteristics of CTMA-bentonites on their adsorption capacity was studied. It was shown that adsorption of toluene depended on homogeneous interlayer space associated with arrangements of CTMA+ paraffin-monolayer and bilayer models, accompanied by a high degree ordering of the carbon chain of organic cation in both arrangements. However, packing density would not have an evident influence on the retention capacity of these materials. The solids obtained were characterized by chemical analysis, X-ray diffractions and infrared spectroscopy. Toluene adsorption was measured by UV-visible spectrophotometer. Adsorption capacity was studied by determining adsorption isotherms and adsorption coefficient calculation. The adsorption isotherms were straight-line indicating a partition phenomenon of toluene between the aqueous and organic phase present in organophilic bentonites.

  4. Flow structure of steam-water mixed spray

    International Nuclear Information System (INIS)

    Sanada, Toshiyuki; Mitsuhashi, Yuki; Mizutani, Hiroya; Saito, Takayuki

    2010-01-01

    In this study, the flow structure of a steam-water mixed spray is studied both numerically and experimentally. The velocity and pressure profiles of single-phase flow are calculated using numerical methods. On the basis of the calculated flow fields, the droplet behavior is predicted by a one-way interaction model. This numerical analysis reveals that the droplets are accelerated even after they are sprayed from the nozzle. Experimentally, the mixed spray is observed using an ultra-high-speed video camera, and the velocity field is measured by using the oarticle image velocimetry (PIV) technique. Along with this PIV velocity field measurement, the velocities and diameters of droplets are measured by phase Doppler anemometry. Furthermore, the mixing process of steam and water and the atomization process of a liquid film are observed using a transparent nozzle. High-speed photography observations reveal that the flow inside the nozzle is annular flow and that most of the liquid film is atomized at the nozzle throat and nozzle outlet. Finally, the optimum mixing method for steam and water is determined.

  5. Flow structure of steam-water mixed spray

    Energy Technology Data Exchange (ETDEWEB)

    Sanada, Toshiyuki, E-mail: ttsanad@ipc.shizuoka.ac.j [Department of Mechanical Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561, Shizuoka (Japan); Mitsuhashi, Yuki; Mizutani, Hiroya; Saito, Takayuki [Department of Mechanical Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561, Shizuoka (Japan)

    2010-12-15

    In this study, the flow structure of a steam-water mixed spray is studied both numerically and experimentally. The velocity and pressure profiles of single-phase flow are calculated using numerical methods. On the basis of the calculated flow fields, the droplet behavior is predicted by a one-way interaction model. This numerical analysis reveals that the droplets are accelerated even after they are sprayed from the nozzle. Experimentally, the mixed spray is observed using an ultra-high-speed video camera, and the velocity field is measured by using the oarticle image velocimetry (PIV) technique. Along with this PIV velocity field measurement, the velocities and diameters of droplets are measured by phase Doppler anemometry. Furthermore, the mixing process of steam and water and the atomization process of a liquid film are observed using a transparent nozzle. High-speed photography observations reveal that the flow inside the nozzle is annular flow and that most of the liquid film is atomized at the nozzle throat and nozzle outlet. Finally, the optimum mixing method for steam and water is determined.

  6. Structure design of water discharge surge tank of nuclear power plant

    International Nuclear Information System (INIS)

    Wang Fang; Hou Shuqiang

    2015-01-01

    Drainage is an important function of water discharge surge tank in nuclear power plant. There is little wall and beam inside the water discharge surge tank due to the requirement of major work, which is different from the general structure. Taking water discharge surge tank of nuclear power plant for example, concerned problems are expatiated in the structure scheme of water discharge surge tank, and important structural components are analyzed. Structural analysis model is established by ANSYS finite element analysis. A comprehensive and numerical analysis is performed for different combinations of structural model, and the internal force of structure is extracted. Finally, suggestions for design of similar structure are proposed. (authors)

  7. Extracorporeal membrane oxygenation for refractory cardiac arrest

    Directory of Open Access Journals (Sweden)

    Steven A Conrad

    2017-01-01

    Full Text Available Extracorporeal cardiopulmonary resuscitation (ECPR is the use of rapid deployment venoarterial (VA extracorporeal membrane oxygenation to support systemic circulation and vital organ perfusion in patients in refractory cardiac arrest not responding to conventional cardiopulmonary resuscitation (CPR. Although prospective controlled studies are lacking, observational studies suggest improved outcomes compared with conventional CPR when ECPR is instituted within 30-60 min following cardiac arrest. Adult and pediatric patients with witnessed in-hospital and out-of-hospital cardiac arrest and good quality CPR, failure of at least 15 min of conventional resuscitation, and a potentially reversible cause for arrest are candidates. Percutaneous cannulation where feasible is rapid and can be performed by nonsurgeons (emergency physicians, intensivists, cardiologists, and interventional radiologists. Modern extracorporeal systems are easy to prime and manage and are technically easy to manage with proper training and experience. ECPR can be deployed in the emergency department for out-of-hospital arrest or in various inpatient units for in-hospital arrest. ECPR should be considered for patients with refractory cardiac arrest in hospitals with an existing extracorporeal life support program, able to provide rapid deployment of support, and with resources to provide postresuscitation evaluation and management.

  8. Community Structure Of Reef Fish In Eastern Luwu Water Territory

    Directory of Open Access Journals (Sweden)

    Henny Tribuana Cinnawara

    2015-01-01

    Full Text Available Abstract One bio-indicators the condition of coral reefs is a presence of reef fish. The purpose of research is to determine species composition abundance distribution and structure of reef fish communities in these waters. Data collection was conducted in April at six locations in the north and the south eastern Luwu. Mechanical Underwater Visual Cencus UVC and transect method Line intercept Transec LIT with SCUBA equipment used for research data collection. Total reef fish species collected as many as 366 species belonging to 31 families consisting of 150 species of fish target fish consumption 10 species of indicator fish indicator species 206 types of major fissh. The most dominant indicator type of fish is Chaetodon octofasciatus while the major dominant family Pomacentridae Labridae and Apogonidae. Diversity index values ranged from 2.145 to 3.408. Dominance index C is in the range of 0.056 to 0.298. The result is expected to be a reference literature as basic data for the management of reef fish especially in the waters of eastern Luwu.

  9. Comparison of crack arrest methodologies

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    The ASTM Cooperative Test Program Data were used to compare the static (K/sub Ia/) and dynamic (K/sud ID/, K/sub IDm/) approaches to crack arrest. K/sub Ia/ is not dependent on K/sub Q/. This is consistent with the requirements of the static approach, but not the dynamic one which requires that K/sub Ia/ decrease with K/sub Q/ if K/sub ID/ (= K/sub IDm/) is a constant. K/sub ID/ increases systematically with K/sub Q/ at a rate that is consistent with calculations based on the use of a constant value for K/sub Ia/ which is equal to its measured mean value. Only in the limiting case of very short crack jumps (associated with very low average crack speeds) can K/sub ID/ be identified as a minimum value at which K/sub ID/ = K/sub IDm/. In this case K/sub IDm/ approx. K/sub Ia/ approx. K/sub Im/. The latter is the idealized minimum value of K that will support the continued propagation of a running crack

  10. Impressed current cathodic protection of deep water structures

    Digital Repository Service at National Institute of Oceanography (India)

    Venkatesan, R.

    that the cathodic protection design approaches for shallow water may not be adequate for deeper water. This paper discusses on environmental factors encountered in deep water and their effect on cathodic protection behaviour of steel. Further, current CP design...

  11. Dental Calculus Arrest of Dental Caries

    OpenAIRE

    Keyes, Paul H.; Rams, Thomas E.

    2016-01-01

    Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human t...

  12. Promoting inclusive water governance and forecasting the structure of water consumption based on compositional data: A case study of Beijing.

    Science.gov (United States)

    Wei, Yigang; Wang, Zhichao; Wang, Huiwen; Yao, Tang; Li, Yan

    2018-09-01

    Water is centrally important for agricultural security, environment, people's livelihoods, and socio-economic development, particularly in the face of extreme climate changes. Due to water shortages in many cities, the conflicts between various stakeholders and sectors over water use and allocation are becoming more common and intense. Effective inclusive governance of water use is critical for relieving water use conflicts. In addition, reliable forecasting of the structure of water usage among different sectors is a basic need for effective water governance planning. Although a large number of studies have attempted to forecast water use, little is known about the forecasted structure and trends of water use in the future. This paper aims to develop a forecasting model for the structure of water usage based on compositional data. Compositional data analysis is an effective approach for investigating the internal structure of a system. A host of data transformation methods and forecasting models were adopted and compared in order to derive the best-performing model. According to mean absolute percent error for compositional data (CoMAPE), a hyperspherical-transformation-based vector autoregression model for compositional data (VAR-DRHT) is the best-performing model. The proportions of the agricultural, industrial, domestic and environmental water will be 6.11%, 5.01%, 37.48% and 51.4% by 2020. Several recommendations for water inclusive development are provided to give a better account for the optimization of the water use structure, alleviation of water shortages, and improving stake holders' wellbeing. Overall, although we focus on groundwater, this study presents a powerful framework broadly applicable to resource management. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Sex Disparities in Arrest Outcomes for Domestic Violence

    Science.gov (United States)

    Hamilton, Melissa; Worthen, Meredith G. F.

    2011-01-01

    Domestic violence arrests have been historically focused on protecting women and children from abusive men. Arrest patterns continue to reflect this bias with more men arrested for domestic violence compared to women. Such potential gender variations in arrest patterns pave the way to the investigation of disparities by sex of the offender in…

  14. Structural analysis of fuel rod applied to pressurized water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Faria, Danilo P.; Pinheiro, Andre Ricardo M.; Lotto, André A., E-mail: danilo.pinheiro@marinha.mil.br [Centro Tecnológico da Marinha em São Paulo (CTMSP), São Paulo, SP (Brazil)

    2017-07-01

    The design of fuel assemblies applied to Pressurized Water Reactors (PWR) has several requirements and acceptance criteria that must be attended for licensing. In the case of PWR fuel rods, an important mechanical structural requirement is to keep the radial stability when submitted to the coolant external pressure. In the framework of the Accident Tolerant Fuel (ATF) program new materials have been studied to replace zirconium based alloys as cladding, including iron-based alloys. In this sense, efforts have been made to evaluate the behavior of these materials under PWR conditions. The present work aims to evaluate the collapse cold pressure of a stainless steel thin-walled tube similar to that used as cladding material of fuel rods by means of the comparison of numeric data, and experimental results. As a result of the simulations, it was observed that the collapse pressure has a value intermediate value between those found by regulatory requirements and analytical calculations. The experiment was carried out for the validation of the computational model using test specimens of thin-walled tubes considering empty tube. The test specimens were sealed at both ends by means of welding. They were subjected to a high pressure device until the collapse of the tubes. Preliminary results obtained from experiments with the empty test specimens indicate that the computational model can be validated for stainless steel cladding, considering the difference between collapse pressure indicated in the regulatory document and the actual limit pressure concerning to radial instability of tubes with the studied characteristics. (author)

  15. Structural basis for catalysis at the membrane-water interface.

    Science.gov (United States)

    Dufrisne, Meagan Belcher; Petrou, Vasileios I; Clarke, Oliver B; Mancia, Filippo

    2017-11-01

    The membrane-water interface forms a uniquely heterogeneous and geometrically constrained environment for enzymatic catalysis. Integral membrane enzymes sample three environments - the uniformly hydrophobic interior of the membrane, the aqueous extramembrane region, and the fuzzy, amphipathic interfacial region formed by the tightly packed headgroups of the components of the lipid bilayer. Depending on the nature of the substrates and the location of the site of chemical modification, catalysis may occur in each of these environments. The availability of structural information for alpha-helical enzyme families from each of these classes, as well as several beta-barrel enzymes from the bacterial outer membrane, has allowed us to review here the different ways in which each enzyme fold has adapted to the nature of the substrates, products, and the unique environment of the membrane. Our focus here is on enzymes that process lipidic substrates. This article is part of a Special Issue entitled: Bacterial Lipids edited by Russell E. Bishop. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Water permeability evaluation of hollow cylindrical reinforced concrete structure by means of long-term water penetration test with pressure

    International Nuclear Information System (INIS)

    Fujiwara, Ai; Miura, Norihiko; Konishi, Kazuhiro; Tsuji, Yukikazu

    2005-01-01

    In order to evaluate initial permeability of large concrete structure, hollow cylindrical reinforced concrete structure, having 6 m in outer diameter, 6 m in height, 1 m in thickness, had been tested by means of 0.25 MPa of outside water pressure. As the results, although surface cracking and partial separation of joint had been observed at the inner side, no water permeation through concrete could be happened even after 5.5 years. After this test, concrete core specimen showed less water penetration within the depth of concrete cover of reinforcement. Thus it was verified that this concrete structure had very high water-tightness, and that the initial average water permeability was estimated to be about 1.6 x 10 -12 m/s. (author)

  17. SMC1-Mediated Intra-S-Phase Arrest Facilitates Bocavirus DNA Replication

    Science.gov (United States)

    Luo, Yong; Deng, Xuefeng; Cheng, Fang; Li, Yi

    2013-01-01

    Activation of a host DNA damage response (DDR) is essential for DNA replication of minute virus of canines (MVC), a member of the genus Bocavirus of the Parvoviridae family; however, the mechanism by which DDR contributes to viral DNA replication is unknown. In the current study, we demonstrate that MVC infection triggers the intra-S-phase arrest to slow down host cellular DNA replication and to recruit cellular DNA replication factors for viral DNA replication. The intra-S-phase arrest is regulated by ATM (ataxia telangiectasia-mutated kinase) signaling in a p53-independent manner. Moreover, we demonstrate that SMC1 (structural maintenance of chromosomes 1) is the key regulator of the intra-S-phase arrest induced during infection. Either knockdown of SMC1 or complementation with a dominant negative SMC1 mutant blocks both the intra-S-phase arrest and viral DNA replication. Finally, we show that the intra-S-phase arrest induced during MVC infection was caused neither by damaged host cellular DNA nor by viral proteins but by replicating viral genomes physically associated with the DNA damage sensor, the Mre11-Rad50-Nbs1 (MRN) complex. In conclusion, the feedback loop between MVC DNA replication and the intra-S-phase arrest is mediated by ATM-SMC1 signaling and plays a critical role in MVC DNA replication. Thus, our findings unravel the mechanism underlying DDR signaling-facilitated MVC DNA replication and demonstrate a novel strategy of DNA virus-host interaction. PMID:23365434

  18. Genetic mutation in Korean patients of sudden cardiac arrest as a surrogating marker of idiopathic ventricular arrhythmia.

    Science.gov (United States)

    Son, Myoung Kyun; Ki, Chang-Seok; Park, Seung-Jung; Huh, June; Kim, June Soo; On, Young Keun

    2013-07-01

    Mutation or common intronic variants in cardiac ion channel genes have been suggested to be associated with sudden cardiac death caused by idiopathic ventricular tachyarrhythmia. This study aimed to find mutations in cardiac ion channel genes of Korean sudden cardiac arrest patients with structurally normal heart and to verify association between common genetic variation in cardiac ion channel and sudden cardiac arrest by idiopathic ventricular tachyarrhythmia in Koreans. Study participants were Korean survivors of sudden cardiac arrest caused by idiopathic ventricular tachycardia or fibrillation. All coding exons of the SCN5A, KCNQ1, and KCNH2 genes were analyzed by Sanger sequencing. Fifteen survivors of sudden cardiac arrest were included. Three male patients had mutations in SCN5A gene and none in KCNQ1 and KCNH2 genes. Intronic variant (rs2283222) in KCNQ1 gene showed significant association with sudden cardiac arrest (OR 4.05). Four male sudden cardiac arrest survivors had intronic variant (rs11720524) in SCN5A gene. None of female survivors of sudden cardiac arrest had SCN5A gene mutations despite similar frequencies of intronic variants between males and females in 55 normal controls. Common intronic variant in KCNQ1 gene is associated with sudden cardiac arrest caused by idiopathic ventricular tachyarrhythmia in Koreans.

  19. Arrested larval development in cattle nematodes.

    Science.gov (United States)

    Armour, J; Duncan, M

    1987-06-01

    Most economically important cattle nematodes are able to arrest their larval development within the host - entering a period of dormancy or hypobiosis. Arrested larvae have a low death rate, and large numbers can accumulate in infected cattle during the grazing season. Because of this, outbreaks of disease caused by such nematodes can occur at times when recent infection with the parasites could not have occurred, for example during winter in temperature northern climates when cattle are normally housed. The capacity to arrest is a heritable trait. It is seen as an adaptation by the parasite to avoid further development to its free-living stages during times when the climate is unsuitable for free-living survival. But levels of arrestment can vary markedly in different regions, in different cattle, and under different management regimes. Climatic factors, previous conditioning, host immune status, and farm management all seem to affect arrestment levels. In this article, James Armour and Mary Duncan review the biological basis of the phenomenon, and discuss the apparently conflicting views on how it is controlled.

  20. Investigation of the Structures and Energy Landscapes of Thiocyanate-Water Clusters

    Directory of Open Access Journals (Sweden)

    Lewis C. Smeeton

    2017-03-01

    Full Text Available The Basin Hopping search method is used to find the global minima (GM and map the energy landscapes of thiocyanate-water clusters, (SCN−(H2On with 3–50 water molecules, with empirical potentials describing the ion-water and water-water interactions. (It should be noted that beyond n = 23, the lowest energy structures were only found in 1 out of 8 searches so they are unlikely to be the true GM but are indicative low energy structures. As for pure water clusters, the low energy isomers of thiocyanate-water clusters show a preponderance of fused water cubes and pentagonal prisms, with the weakly solvated thiocyanate ion lying on the surface, replacing two water molecules along an edge of a water polyhedron and with the sulfur atom in lower coordinated sites than nitrogen. However, by comparison with Density Functional Theory (DFT calculations, the empirical potential is found to overestimate the strength of the thiocyanate-water interaction, especially O–H⋯S, with low energy DFT structures having lower coordinate N and (especially S atoms than for the empirical potential. In the case of these finite ion-water clusters, the chaotropic (“disorder-making” thiocyanate ion weakens the water cluster structure but the water molecule arrangement is not significantly changed.

  1. Dynamics and structure of water-bitumen mixtures

    DEFF Research Database (Denmark)

    Lemarchand, Claire; Greenfield, Michael L.; Hansen, Jesper Schmidt

    2016-01-01

    Systems of Cooee bitumen and water up to 4% mass are studied by molecular dynamics simulations. The cohesive energy density of the system is shown to decrease with an increasing water content. This decrease is due mainly to an increase in the interaction energy which is not high enough to counter......Systems of Cooee bitumen and water up to 4% mass are studied by molecular dynamics simulations. The cohesive energy density of the system is shown to decrease with an increasing water content. This decrease is due mainly to an increase in the interaction energy which is not high enough...... droplets being more stable at the highest temperature simulated. The droplet is mainly located close to the saturates molecules in bitumen. Finally, it is shown that the water dynamics is much slower in bitumen than in pure water because it is governed by the diffusion of the droplet and not of the single...

  2. Slow Dynamics and Structure of Supercooled Water in Confinement

    Directory of Open Access Journals (Sweden)

    Gaia Camisasca

    2017-04-01

    Full Text Available We review our simulation results on properties of supercooled confined water. We consider two situations: water confined in a hydrophilic pore that mimics an MCM-41 environment and water at interface with a protein. The behavior upon cooling of the α relaxation of water in both environments is well interpreted in terms of the Mode Coupling Theory of glassy dynamics. Moreover, we find a crossover from a fragile to a strong regime. We relate this crossover to the crossing of the Widom line emanating from the liquid-liquid critical point, and in confinement we connect this crossover also to a crossover of the two body excess entropy of water upon cooling. Hydration water exhibits a second, distinctly slower relaxation caused by its dynamical coupling with the protein. The crossover upon cooling of this long relaxation is related to the protein dynamics.

  3. Reactor water spontaneous circulation structure in reactor pressure vessel

    International Nuclear Information System (INIS)

    Takahashi, Kazumi

    1998-01-01

    The gap between the inner wall of a reactor pressure vessel of a BWR type reactor and a reactor core shroud forms a down comer in which reactor water flows downwardly. A feedwater jacket to which feedwater at low temperature is supplied is disposed at the outer circumference of the pressure vessel just below a gas/water separator. The reactor water at the outer circumferential portion just below the air/water separator is cooled by the feedwater jacket, and the feedwater after cooling is supplied to the feedwater entrance disposed below the feedwater jacket by way of a feedwater introduction line to supply the feedwater to the lower portion of the down comer. This can cool the reactor water in the down comer to increase the reactor water density in the down comer thereby forming strong downward flows and promote the recycling of the reactor water as a whole. With such procedures, the reactor water can be recycled stably only by the difference of the specific gravity of the reactor water without using an internal pump. In addition, the increase of the height of the pressure vessel can be suppressed. (I.N.)

  4. A One-Dimensional Hydrodynamic and Water Quality Model for a Water Transfer Project with Multihydraulic Structures

    Directory of Open Access Journals (Sweden)

    Yujun Yi

    2017-01-01

    Full Text Available The long Middle Route of the South to North Water Transfer Project is composed of complex hydraulic structures (aqueduct, tunnel, control gate, diversion, culvert, and diverted siphon, which generate complex flow patterns. It is vital to simulate the flow patterns through hydraulic structures, but it is a challenging work to protect water quality and maintain continuous water transfer. A one-dimensional hydrodynamic and water quality model was built to understand the flow and pollutant movement in this project. Preissmann four-point partial-node implicit scheme was used to solve the governing equations in this study. Water flow and pollutant movement were appropriately simulated and the results indicated that this water quality model was comparable to MIKE 11 and had a good performance and accuracy. Simulation accuracy and model uncertainty were analyzed. Based on the validated water quality model, six pollution scenarios (Q1 = 10 m3/s, Q2 = 30 m3/s, and Q3 = 60 m3/s for volatile phenol (VOP and contaminant mercury (Hg were simulated for the MRP. Emergent pollution accidents were forecasted and changes of water quality were analyzed according to the simulations results, which helped to guarantee continuously transferring water for a large water transfer project.

  5. TAPWAT: Definition structure and applications for modelling drinking water treatment

    NARCIS (Netherlands)

    Versteegh JFM; Gaalen FW van; Rietveld LC; Evers EG; Aldenberg TA; Cleij P; Technische Universiteit Delft; LWD

    2001-01-01

    The 'Tool for the Analysis of the Production of drinking WATer' (TAPWAT) model has been developed for describing drinking-water quality in integral studies in the context of the Environmental Policy Assessment of the RIVM. The model consists of modules that represent individual steps in a treatment

  6. Probing water structure and transport in proton exchange membranes

    NARCIS (Netherlands)

    Ling, X.

    2018-01-01

    Proton exchange membrane fuel cells (PEMFCs) have attracted tremendous attention as alternative energy sources because of their high energy density and practically zero greenhouse gas emission - water is their only direct by-product. Critical to the function of PEMFCs is fast proton and water

  7. Procedure for developing biological input for the design, location, or modification of water-intake structures

    Energy Technology Data Exchange (ETDEWEB)

    Neitzel, D.A.; McKenzie, D.H.

    1981-12-01

    To minimize adverse impact on aquatic ecosystems resulting from the operation of water intake structures, design engineers must have relevant information on the behavior, physiology and ecology of local fish and shellfish. Identification of stimulus/response relationships and the environmental factors that influence them is the first step in incorporating biological information in the design, location or modification of water intake structures. A procedure is presented in this document for providing biological input to engineers who are designing, locating or modifying a water intake structure. The authors discuss sources of stimuli at water intakes, historical approaches in assessing potential/actual impact and review biological information needed for intake design.

  8. IMPROVING STRUCTURAL INTEGRITY MONITORING CAPABILITY FOR WATER MAINS: COLLABORATION EFFORTS AND OPPORTUNITIES

    Science.gov (United States)

    The structural integrity of the approximately 1,000,000 miles of U.S. water mains is important to both immediate and long-term drinking water quality and availability. As pipes wear out, leaks and main breaks increase, as well as the associated occurrences of water loss and low-...

  9. Location of cardiac arrest and impact of pre-arrest chronic disease and medication use on survival

    DEFF Research Database (Denmark)

    Granfeldt, Asger; Wissenberg, Mads; Hansen, Steen Møller

    2017-01-01

    location and a higher mortality can be explained by differences in chronic diseases and medication. METHODS: We identified 27,771 out-of-hospital cardiac arrest patients ≥18 years old from the Danish Cardiac Arrest Registry (2001-2012). Using National Registries, we identified pre-arrest chronic disease......INTRODUCTION: Cardiac arrest in a private location is associated with a higher mortality when compared to public location. Past studies have not accounted for pre-arrest factors such as chronic disease and medication. AIM: To investigate whether the association between cardiac arrest in a private...

  10. The constructional design of cooling water discharge structures on German rivers

    International Nuclear Information System (INIS)

    Geldner, P.; Zimmermann, C.

    1975-11-01

    The present compilation of structures for discharging cooling water from power stations into rivers is an attempt to make evident developments in the constructional design of such structures and to give reasons for special structure shapes. A complete collection of all structures built in Germany, however, is difficult to realize because of the large number of power stations. For conventionally heated power stations therefore only a selection was made, while nuclear power stations in operation or under construction could almost completely be taken into account. For want of sufficient quantities of water for river water cooling, projected power stations are now almost exclusively designed for closed-circuit cooling so that the required discharge structures for elutrition water from the cooling towers as well as for the emergency and secondary cooling circuits have to be designed only for small amounts of water. (orig./HP) [de

  11. Mathematical Model to Predict the Permeability of Water Transport in Concrete Structure

    OpenAIRE

    Solomon Ndubuisi Eluozo

    2013-01-01

    Mathematical model to predict the permeability of water transport in concrete has been established, the model is to monitor the rate of water transport in concrete structure. The process of this water transport is based on the constituent in the mixture of concrete. Permeability established a relation on the influence of the micropores on the constituent that made of concrete, the method of concrete placement determine the rate of permeability deposition in concrete structure, permeability es...

  12. Water-mediated ionic interactions in protein structures

    Indian Academy of Sciences (India)

    ISHWARYA( R SARANI( M KIRTI VAISHNAVI and K SEKAR. Supplementary table 1. List of complete water-mediated ionic interactions formed by different combinations of charged atoms and their corresponding occurrences. S. No. Type.

  13. Rotavirus replication is correlated with S/G2 interphase arrest of the host cell cycle.

    Directory of Open Access Journals (Sweden)

    Selene Glück

    Full Text Available In infected cells rotavirus (RV replicates in viroplasms, cytosolic structures that require a stabilized microtubule (MT network for their assembly, maintenance of the structure and perinuclear localization. Therefore, we hypothesized that RV could interfere with the MT-breakdown that takes place in mitosis during cell division. Using synchronized RV-permissive cells, we show that RV infection arrests the cell cycle in S/G2 phase, thus favoring replication by improving viroplasms formation, viral protein translation, and viral assembly. The arrest in S/G2 phase is independent of the host or viral strain and relies on active RV replication. RV infection causes cyclin B1 down-regulation, consistent with blocking entry into mitosis. With the aid of chemical inhibitors, the cytoskeleton network was linked to specific signaling pathways of the RV-induced cell cycle arrest. We found that upon RV infection Eg5 kinesin was delocalized from the pericentriolar region to the viroplasms. We used a MA104-Fucci system to identify three RV proteins (NSP3, NSP5, and VP2 involved in cell cycle arrest in the S-phase. Our data indicate that there is a strong correlation between the cell cycle arrest and RV replication.

  14. Cell cycle arrest induced by radiation

    International Nuclear Information System (INIS)

    Okaichi, Yasuo; Matsumoto, Hideki; Ohnishi, Takeo

    1994-01-01

    It is known that various chemical reactions, such as cell cycle arrest, DNA repair and cell killing, can occur within the cells when exposed to ionizing radiation and ultraviolet radiation. Thus protein dynamics involved in such chemical reactions has received considerable attention. In this article, cell cycle regulation is first discussed in terms of the G2/M-phase and the G1/S-phase. Then, radiation-induced cell cycle arrest is reviewed. Cell cycle regulation mechanism involved in the G2 arrest, which is well known to occur when exposed to radiation, has recently been investigated using yeasts. In addition, recent study has yielded a noticeable finding that the G1 arrest can occur with intracellular accumulation of p53 product following ionization radiation. p53 is also shown to play an extremely important role in both DNA repair and cell killing due to DNA damage. Studies on the role of genes in protein groups induced by radiation will hold promise for the elucidation of cell cycle mechanism. (N.K.) 57 refs

  15. Exploring the effectiveness of sustainable water management structures in the Upper Pungwe river basin

    Science.gov (United States)

    Nyikadzino, B.; Chibisa, P.; Makurira, H.

    The study endeavoured to assess the effectiveness of stakeholder structures and their participation in sustainable water resources management in the Upper Pungwe river basin shared by Zimbabwe and Mozambique. The study sought to assess the level and effectiveness of stakeholder, gender and the vulnerable groups representation in sustainable water resources management as well as the whole stakeholder participation process. The study employed both qualitative and quantitative methods for data collection and analysis. Sampling data was obtained from 15 stakeholder representatives (councillors) constituting Pungwe Subcatchment Council, 30 water users ranging from small scale to large scale users and professionals in water resources management. Two different questionnaires and three structured interviews were administered during the study. Water permit database, financial reports and other source documents were also analysed. The study established that the sustainability and effectiveness of stakeholder structures and their participation in water resources management is being compromised by lack of stakeholder awareness. Water utilisation is very high in the subcatchment (99%) while women participation is still low (20%). The study therefore recommends the use of quotas for the participation of women in stakeholder structures. Stakeholder structures are encouraged to intensify stakeholder awareness on issues of river protection, efficient water use and pollution control. Further research is recommended to be carried out on the effectiveness of stakeholder structures in combating water pollution and enhancing river protection.

  16. The structure of water quality monitoring in the disaster area

    International Nuclear Information System (INIS)

    Yoshida, Nobuo

    2012-01-01

    Described are monitoring systems of water environment at usual times and after the 2011 Tohoku Earthquake and Tsunami Disaster, and measures taken by the Ministry of the Environment (ME) for radioactive substances in the water environment. At usual times, the monitoring of hazardous substance in water environment is conducted by local governments. At/after the Disaster, ME conducted the monitoring investigation concerning the environmental quality standards and toxicants like dioxins in the river, sea and groundwater from late May to late July, 2011 because undesirable effects on health and life of the residents had been feared due to possible leak of hazardous substances in public water area and underground water of victim prefectures, Aomori, Iwate, Miyagi, Fukushima and Ibaraki. As the results, no high contamination due to the Disaster was found, and a part of regions exhibited the slight chemical contamination, where continuous and additional monitoring was to be kept locally with guidance of drinking the concerned well water. ME measured radioactive iodine and cesium at 29 places of Fukushima rivers to find <65 and <30,000 Bq/kg, respectively, of 4 spots of river bed material alone (late May); then Cs 32 Bq/L in water at 1 spot and <26,000 Bq/kg in bed at all places after rain (early July). In groundwater, no radioactive nuclides above were detected in any of 111 places of Fukushima Prefecture (late June to early August). Cs was not found in sea water of 9 places of concerned prefectures, but was in the sea bottom soil, <1,380 Bq/kg (middle June). As well, local governments measured those two radioactive nuclides in water and ambient dose rate of 551 sea bathing beaches (late May to early Oct.) and found only one beach (Iwaki City, Fukushima) inappropriate for swimming play. Hereafter, ME is still to investigate the bed material of public water area and to continue to monitor the marine environment in cooperation with related authorities. (T.T.)

  17. Trends and Consumption Structures of China’s Blue and Grey Water Footprint

    Directory of Open Access Journals (Sweden)

    Huixiao Wang

    2018-04-01

    Full Text Available Water footprint has become a common method to study the water resources utilization in recent years. By using input–output analysis and dilution theory, the internal water footprint, blue water footprint and grey water footprint of China from 2002 to 2012 were estimated, and the consumption structure of water footprint and virtual water trade were analyzed. The results show: (1 From 2002 to 2012, the average annual internal water footprint was 3.83 trillion m3 in China, of which the blue water footprint was 0.25 trillion m3, and the grey water footprint was 3.58 trillion m3 (with Grade III water standard accounting; both the internal water footprint and grey water footprint experienced decreasing trends from 2002 to 2012, except for a dramatic increase in 2010; (2 Average annual virtual blue water footprint was the greatest in agriculture (39.2%, while tertiary industry (27.5% and food and tobacco processing (23.7% were the top two highest for average annual virtual grey water footprint; (3 Virtual blue water footprint in most sectors showed increasing trends due to the increase of final demand, while virtual grey water footprint in most sectors showed decreasing trends due to the decreases of total return water coefficients and conversion coefficients of virtual grey water footprint; (4 For water resources, China was self-reliant: the water used for producing the products and services to meet domestic consumption was taken domestically; meanwhile, China exported virtual water to other countries, which aggravated the water stress in China.

  18. Structural evaluation report of piping and support structure for design-changed hot-water layer system

    International Nuclear Information System (INIS)

    Ryu, Jeong Soo

    1998-05-01

    After hot-water layer system had been installed, the verification tests to reduce the radiation level at the top of reactor pool were performed many times. The major goal of this report is to assess the structural integrity on the piping and the support structures of design-changed hot-water layer system. The piping stress analysis was performed by using ADLPIPE program for the pump suction line and the pump discharge line subjected to dead weight, pressure, thermal expansion and seismic loadings. The stress analysis of the support structure was carried out using the reaction forces obtained from the piping stress analysis. The results of structural evaluation for the pipings and the support structures showed that the structural acceptance criteria were satisfied, in compliance with ASME, subsection ND for the piping and subsection NF for the support structures. Therefore based on the results of the analysis and the design, the structural integrity on the piping and the support structures of design-changed hot-water system was proved. (author). 9 refs., 9 tabs., 14 figs

  19. 32 CFR 935.125 - Citation in place of arrest.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Citation in place of arrest. 935.125 Section 935... INSULAR REGULATIONS WAKE ISLAND CODE Peace Officers § 935.125 Citation in place of arrest. In any case in which a peace officer may make an arrest without a warrant, he may issue and serve a citation if he...

  20. Transient Central Diabetes Insipidus and Marked Hypernatremia following Cardiorespiratory Arrest

    Directory of Open Access Journals (Sweden)

    Sahar H. Koubar

    2017-01-01

    Full Text Available Central Diabetes Insipidus is often an overlooked complication of cardiopulmonary arrest and anoxic brain injury. We report a case of transient Central Diabetes Insipidus (CDI following cardiopulmonary arrest. It developed 4 days after the arrest resulting in polyuria and marked hypernatremia of 199 mM. The latter was exacerbated by replacing the hypotonic urine by isotonic saline.

  1. An Audit Of Perioperative Cardiac Arrest At Lagos University ...

    African Journals Online (AJOL)

    Objective: Intraoperative cardiac arrests are not uncommon and are related to both surgical and anaesthetic factors. This study aimed to examine the factors which predispose to a periopeartive cardiac arrest, to assess the appropriateness of therapy and the outcome. Materials and Methods: All perioperative cardiac arrests ...

  2. Structural material anomaly detection system using water chemistry data

    International Nuclear Information System (INIS)

    Asakura, Yamato; Nagase, Makoto; Uchida, Shunsuke; Ohsumi, Katsumi.

    1992-01-01

    The concept of an advanced water chemistry diagnosis system for detection of anomalies and preventive maintenance of system components is proposed and put into a concrete form. Using the analogy to a medical inspection system, analyses of water chemistry change will make it possible to detect symptoms of anomalies in system components. Then, correlations between water chemistry change and anomaly occurrence in the components of the BWR primary cooling system are analyzed theoretically. These fragmentary correlations are organized and reduced to an algorithm for the on-line diagnosis system using on-line monitoring data, pH and conductivity. By using actual plant data, the on-line diagnosis model system is verified to be applicable for early and automatic finding of the anomaly cause and for timely supply of much diagnostic information to plant operators. (author)

  3. Structural material anomaly detection system using water chemistry data, (7)

    International Nuclear Information System (INIS)

    Nagase, Makoto; Uchida, Shunsuke; Asakura, Yamato; Ohsumi, Katsumi.

    1993-01-01

    A method to detect small changes in water quality and diagnose their causes by analyzing on-line conductivity and pH data was proposed. Laboratory tests showed that effective noise reduction of measured on-line data could be got by using median filter to detect small changes of conductivity ; a relative change of 0.001 μS/cm was distinguishable. By simulating the changes of pH and conductivity in the reactor water against a small concentration change of sodium ion or sulfate ion in the feedwater, it was found that an adequate elapsed time for the diagnosis was 4 h from the start of the concentration change. A conductivity difference of 0.001 μS/cm in the reactor water made it theoretically possible to distinguish between a sodium ion concentration change of 4.6 ppt and a sulfate ion concentration change of 9.6 ppt in the feedwater. (author)

  4. Witnessed arrest, but not delayed bystander cardiopulmonary resuscitation improves prehospital cardiac arrest survival.

    Science.gov (United States)

    Vukmir, R B

    2004-05-01

    This study correlated the effect of witnessing a cardiac arrest and instituting bystander CPR (ByCPR), as a secondary end point in a study evaluating the effect of bicarbonate on survival. This prospective, randomised, double blinded clinical intervention trial enrolled 874 prehospital cardiopulmonary arrest patients encountered in a prehospital urban, suburban, and rural regional emergency medical service (EMS) area. This group underwent conventional advanced cardiac life support intervention followed by empiric early administration of sodium bicarbonate (1 mEq/l), monitoring conventional resuscitation parameters. Survival was measured as presence of vital signs on emergency department (ED) arrival. Data were analysed using chi(2) with Pearson correlation and odds ratio where appropriate. The overall survival rate was 13.9% (110 of 792) of prehospital cardiac arrest patients. The mean (SD) time until provision of bystander cardiopulmonary resuscitation (ByCPR) by laymen was 2.08 (2.77) minutes, and basic life support (BLS) by emergency medical technicians was 6.62 (5.73) minutes. There was improved survival noted with witnessed cardiac arrest-a 2.2-fold increase in survival, 18.9% (76 of 402) versus 8.6% (27 of 315) compared with unwitnessed arrests (ptwo minutes (p = 0.3752). Survival after prehospital cardiac arrest is more likely when witnessed, but not necessarily when ByCPR was performed by laymen.

  5. Archaeal RNA polymerase arrests transcription at DNA lesions.

    Science.gov (United States)

    Gehring, Alexandra M; Santangelo, Thomas J

    2017-01-01

    Transcription elongation is not uniform and transcription is often hindered by protein-bound factors or DNA lesions that limit translocation and impair catalysis. Despite the high degree of sequence and structural homology of the multi-subunit RNA polymerases (RNAP), substantial differences in response to DNA lesions have been reported. Archaea encode only a single RNAP with striking structural conservation with eukaryotic RNAP II (Pol II). Here, we demonstrate that the archaeal RNAP from Thermococcus kodakarensis is sensitive to a variety of DNA lesions that pause and arrest RNAP at or adjacent to the site of DNA damage. DNA damage only halts elongation when present in the template strand, and the damage often results in RNAP arresting such that the lesion would be encapsulated with the transcription elongation complex. The strand-specific halt to archaeal transcription elongation on modified templates is supportive of RNAP recognizing DNA damage and potentially initiating DNA repair through a process akin to the well-described transcription-coupled DNA repair (TCR) pathways in Bacteria and Eukarya.

  6. Emergence of the Coherent Structure of Liquid Water

    Directory of Open Access Journals (Sweden)

    Ivan Bono

    2012-07-01

    Full Text Available We examine in some detail the interaction of water molecules with the radiative electromagnetic field and find the existence of phase transitions from the vapor phase to a condensed phase where all molecules oscillate in unison, in tune with a self-trapped electromagnetic field within extended mesoscopic space regions (Coherence Domains. The properties of such a condensed phase are examined and found to be compatible with the phenomenological properties of liquid water. In particular, the observed value of critical density is calculated with good accuracy.

  7. Sodium/hydrogen-exchanger inhibition during cardioplegic arrest and cardiopulmonary bypass: an experimental study.

    Science.gov (United States)

    Cox, Charles S; Sauer, Henning; Allen, Steven J; Buja, L Maximilian; Laine, Glen A

    2002-05-01

    We sought to determine whether pretreatment with a sodium/hydrogen-exchange inhibitor (EMD 96 785) improves myocardial performance and reduces myocardial edema after cardioplegic arrest and cardiopulmonary bypass. Anesthetized dogs (n = 13) were instrumented with vascular catheters, myocardial ultrasonic crystals, and left ventricular micromanometers to measure preload recruitable stroke work, maximum rate of pressure rise (positive and negative), and left ventricular end-diastolic volume and pressure. Cardiac output was measured by means of thermodilution. Myocardial tissue water content was determined from sequential biopsy. After baseline measurements, hypothermic (28 degrees C) cardiopulmonary bypass was initiated. Cardioplegic arrest (4 degrees C Bretschneider crystalloid cardioplegic solution) was maintained for 2 hours, followed by reperfusion-rewarming and separation from cardiopulmonary bypass. Preload recruitable stroke work and myocardial tissue water content were measured at 30, 60, and 120 minutes after bypass. EMD 96 785 (3 mg/kg) was given 15 minutes before bypass, and 2 micromol was given in the cardioplegic solution. Control animals received the same volume of saline vehicle. Arterial-coronary sinus lactate difference was similar in both animals receiving EMD 96 785 and control animals, suggesting equivalent myocardial ischemia in each group. Myocardial tissue water content increased from baseline in both animals receiving EMD 96 785 and control animals with cardiopulmonary bypass and cardioplegic arrest but was statistically lower in animals receiving EMD 96 785 compared with control animals (range, 1.0%-1.5% lower in animals receiving EMD 96 785). Preload recruitable stroke work decreased from baseline (97 +/- 2 mm Hg) at 30 (59 +/- 6 mm Hg) and 60 (72 +/- 9 mm Hg) minutes after cardiopulmonary bypass and cardioplegic arrest in control animals; preload recruitable stroke work did not decrease from baseline (98 +/- 2 mm Hg) in animals receiving

  8. Biotechnologies based on simple and structured superlight water for use in biopharmaceutical and biocosmetic field

    International Nuclear Information System (INIS)

    Manzatu, I.; Olariu, L.; Rusu, M.; Zamfir, S.

    2000-01-01

    S.C. Biotehnos S.A. has developed studies to obtain structured aqueous solutions to find biotechnologies that were patented both in this country and abroad. An increasing interest concerning the action of superlight water on biological systems as well as the investigation of possibility of incorporating this type of water in pharmaceutical and cosmetic products encouraged research upon the processes of structuring the deuterium depleted water to establish non-conventional modern biotechnologies. Thus, physico-chemical parameters of interest (pH-value, conductivity, redox potential) were determined for the superlight water systems resulting from structuration process. Also, these studies have dealt with the effects of superlight water and structured aqueous solutions upon cellular breeding, studies of major importance in cell physiology

  9. Dielectric study on hierarchical water structures restricted in cement and wood materials

    International Nuclear Information System (INIS)

    Abe, Fumiya; Nishi, Akihiro; Saito, Hironobu; Asano, Megumi; Watanabe, Seiei; Kita, Rio; Shinyashiki, Naoki; Yagihara, Shin; Fukuzaki, Minoru; Sudo, Seiichi; Suzuki, Youki

    2017-01-01

    Dielectric relaxation processes for mortar observed by broadband dielectric spectroscopy were analyzed in the drying and hydration processes for an aging sample in the frequency region from 1 MHz up to 2 MHz. At least two processes for structured water in the kHz frequency region and another mHz relaxation process affected by ionic behaviors were observed. Comparison of the relaxation parameters obtained for the drying and hydration processes suggests an existence of hierarchical water structures in the exchange of water molecules, which are originally exchanged from free water observed at around 20 GHz. The water molecules reflected in the lower frequency process of the two kHz relaxation processes are more restricted and take more homogeneous structures than the higher kHz relaxation process. These structured water usually hidden in large ionic behaviors for wood samples was observed by electrodes covered by a thin Teflon film, and hierarchical water structures were also suggested for wood samples. Dielectric spectroscopy technique is an effective tool to analyze the new concept of hierarchical water structures in complex materials. (paper)

  10. Radiation-induced G/sub 2/-arrest is reduced by inhibitors of poly(adenosine diphosphoribose) synthetase

    International Nuclear Information System (INIS)

    Rowley, R.

    1985-01-01

    Experiments are in progress to test whether poly(adenosine diphosphoribose) synthesis is required for the induction of G/sub 2/-arrest in growing mammalian cells following X-irradiation. A variety of poly(ADPR) synthetase inhibitors have been tested to determine: 1) whether addition of an inhibitor to X-irradiated CHO cells reduces G/sub 2/-arrest; 2) whether compounds structurally similar to poly-(ADPR) synthetase inhibitors but inactive against this enzyme affect radiation-induced G/sub 2/-arrest and 3) whether the concentration dependence for poly(ADPR) synthetase inhibition matches that for G/sub 2/-arrest reduction. G/sub 2/-arrest was measured in X-irradiated (1.5 Gy) CHO cells using the mitotic cell selection technique. Poly(ADPR) synthetase activity was measured in permeabilized cells by /sup 3/H-NAD incorporation. The synthetase inhibitors used were 3-aminobenzamide, benzamide, nicotinamide, 4-acetyl pyridine, caffeine and theophylline. The inactive compounds used were 3-aminobenzoic acid, benzoic acid, nicotinic acid, adenine, adenosine and 3'-deoxyadenosine. Inhibitors of poly(ADPR) synthetase reduced G/sub 2/-arrest while related compounds which produced no enzyme inhibition did not. The concentration dependencies for G/sub 2/-arrest reduction and enzyme inhibition were similar only for methyl xanthines. Further analysis awaits the determination of intracellular drug concentrations

  11. A study on the water permeability of concrete structures

    International Nuclear Information System (INIS)

    Loadsman, R.V.C.; Acres, D.H.; Stokes, C.J.; Wadeson, L.

    1988-03-01

    This report forms part of the DoE's research programme on the disposal of nuclear waste. The information available on the permeability of concrete and the effects of various factors on this value are reviewed. The effect of defects on the overall permeability of concrete structures is examined and the recorded performance of a range of existing concrete structures is considered with identification of some of the factors that are significant in practice. Deficiencies in the information available on this subject are identified and recommendations for further work are made including a list of structures suitable for future monitoring. (author)

  12. Water structure near single and multi-layer nanoscopic hydrophobic ...

    Indian Academy of Sciences (India)

    Wintec

    We have performed a series of molecular dynamics simulations of water containing two nano- scopic hydrophobic ..... the simulation for l00 ps for equilibration during which ... was further run for a production phase of 100–200 ps depending on ...

  13. TAPWAT: Definition structure and applications for modelling drinking water treatment

    NARCIS (Netherlands)

    Versteegh JFM; van Gaalen FW; Rietveld LC; Evers EG; Aldenberg TA; Cleij P; LWD

    2001-01-01

    Het model TAPWAT (Tool for the Analysis of the Production of drinking WATer), is ontwikkeld om de drinkwaterkwaliteit te beschrijven voor integrale studies in het kader van het planbureau Milieu en Natuur van het RIVM. Het model bestaat uit modules die de individuele zuiveringsstappen van het

  14. Generation of shockwave and vortex structures at the outflow of a boiling water jet

    Science.gov (United States)

    Alekseev, M. V.; Lezhnin, S. I.; Pribaturin, N. A.; Sorokin, A. L.

    2014-12-01

    Results of numerical simulation for shock waves and generation of vortex structures during unsteady outflow of boiling liquid jet are presented. The features of evolution of shock waves and vortex structures formation during unsteady outflow of boiling water are compared with corresponding structures during unsteady gas outflow.

  15. Networked Water Citizen Organisations in Spain: Potential for Transformation of Existing Power Structures in Water Management

    Directory of Open Access Journals (Sweden)

    Nuria Hernández-Mora

    2015-06-01

    Full Text Available The shift from hierarchical-administrative water management toward more transparent, multi-level and participated governance approaches has brought about a shifting geography of players, scales of action, and means of influencing decisions and outcomes. In Spain, where the hydraulic paradigm has dominated since the early 1920s, participation in decisions over water has traditionally been limited to a closed water policy community, made up of economic water users, primarily irrigator associations and hydropower generators, civil engineering corps and large public works companies. The river basin planning process under the Water Framework Directive of the European Union presented a promise of transformation, giving access to non-economic water users, environmental concerns and the wider public to water-related information on planning and decision-making. This process coincided with the consolidation of the use of Information and Communication Technologies (ICTs by the water administration, with the associated potential for information and data generation and dissemination. ICTs are also increasingly used by citizen groups and other interested parties as a way to communicate, network and challenge existing paradigms and official discourses over water, in the broader context of the emergence of 'technopolitics'. This paper investigates if and in what way ICTs may be providing new avenues for participated water resources management and contributing to alter the dominating power balance. We critically analyse several examples where networking possibilities provided by ICTs have enabled the articulation of interest groups and social agents that have, with different degrees of success, questioned the existing hegemonic view over water. The critical review of these cases sheds light on the opportunities and limitations of ICTs, and their relation with traditional modes of social mobilisation in creating new means of societal involvement in water

  16. Thermodynamic and structural signatures of water-driven methane-methane attraction in coarse-grained mW water.

    Science.gov (United States)

    Song, Bin; Molinero, Valeria

    2013-08-07

    Hydrophobic interactions are responsible for water-driven processes such as protein folding and self-assembly of biomolecules. Microscopic theories and molecular simulations have been used to study association of a pair of methanes in water, the paradigmatic example of hydrophobic attraction, and determined that entropy is the driving force for the association of the methane pair, while the enthalpy disfavors it. An open question is to which extent coarse-grained water models can still produce correct thermodynamic and structural signatures of hydrophobic interaction. In this work, we investigate the hydrophobic interaction between a methane pair in water at temperatures from 260 to 340 K through molecular dynamics simulations with the coarse-grained monatomic water model mW. We find that the coarse-grained model correctly represents the free energy of association of the methane pair, the temperature dependence of free energy, and the positive change in entropy and enthalpy upon association. We investigate the relationship between thermodynamic signatures and structural order of water through the analysis of the spatial distribution of the density, energy, and tetrahedral order parameter Qt of water. The simulations reveal an enhancement of tetrahedral order in the region between the first and second hydration shells of the methane molecules. The increase in tetrahedral order, however, is far from what would be expected for a clathrate-like or ice-like shell around the solutes. This work shows that the mW water model reproduces the key signatures of hydrophobic interaction without long ranged electrostatics or the need to be re-parameterized for different thermodynamic states. These characteristics, and its hundred-fold increase in efficiency with respect to atomistic models, make mW a promising water model for studying water-driven hydrophobic processes in more complex systems.

  17. [Ability of typical greenery shrubs of Beijing to adsorb and arrest PM2.5 ].

    Science.gov (United States)

    Liang, Dan; Wang, Bin; Wang, Yun-qi; Zhang, Hui-lan; Yang, Song-nan; Li, Ang

    2014-09-01

    Four typical types of green shrubs of Beijing (Euonymus japonicus, Buxus microphylla, Berberis thunbergii cv. atropurpurea, Taxus cuspidate cv. nana) were selected to study their capacities in adsorbing and arresting PM2.5 using both field observations and air chamber simulations. Concurrently, in order to analyze the pollution characteristics of Beijing in winter and spring, the PM2.5 concentrations of December 2012 to May 2013 were collected. Experimental results showed that: From the gas chamber experiments, the ability to adsorb and arrest PM2.5 was in the order of Berberis thunbergii cv. atropurpurea > Buxus microphylla > Taxus cuspidate cv. nana > Euonymus japonicus, mainly due to the differences in leaf characteristics; Outside measurement results showed that the ability to adsorb and arrest PM2.5 was ranked as Buxus microphylla > Berberis thunbergii cv. atropurpurea > Taxus cuspidate cv. nana > Euonymus japonicus. Chamber simulation and outdoor observation showed that Buxus microphylla and Berberis thunbergii cv. atropurpurea had strong ability to adsorb and arrest PM2.5; Meanwhile, the slight differences between the chamber simulation and outdoor observation results might be related to plant structure. Compared to tree species, the planting condition of shrub species was loose, and it greened quickly; By analyzing the Beijing PM2.5 concentration values in winter and spring, it was found that the PM2.5 concentration was particularly high in the winter of Beijing, and evergreen shrubs maintained the ability to adsorb and arrest PM2.5.

  18. Patterns, structures and regulations of domestic water cycle systems in China

    Science.gov (United States)

    Chu, Junying; Wang, Hao; Wang, Jianhua; Qin, Dayong

    2010-05-01

    Domestic water cycle systems serving as one critical component of artificial water cycle at the catchment's scale, is so closely related to public healthy, human rights and social-economic development, and has gained the highest priority in strategic water resource and municipal infrastructure planning. In this paper, three basic patterns of domestic water cycle systems are identified and analyzed, including rural domestic water system (i.e. primary level), urban domestic water system (i.e. intermediate level) and metropolitan domestic water system (i.e. senior level), with different "abstract-transport-consume-discharge" mechanisms and micro-components of water consumption (such as drinking, cooking, toilet flushing, showering or cleaning). The rural domestic water system is general simple with three basic "abstract-consume-discharge" mechanisms and micro-components of basic water consumption such as drinking, cooking, washing and sanitation. The urban domestic water system has relative complex mechanisms of "abstract-supply-consume-treatment-discharge" and more micro-components of water consumption such as bath, dishwashing or car washing. The metropolitan domestic water system (i.e. senior level) has the most complex mechanisms by considering internal water reuse, external wastewater reclamation, and nutrient recycling processes. The detailed structures for different water cycle pattern are presented from the aspects of water quantity, wastewater quality and nutrients flow. With the speed up of urbanization and development of social-economy in China, those three basic patterns are interacting, transforming and upgrading. According to the past experiences and current situations, urban domestic water system (i.e. intermediate level) is the dominant pattern based on indicator of system number or system scale. The metropolitan domestic water system (i.e. senior level) is the idealized model for the future development and management. Current domestic water system

  19. Prehospital behaviour of patients admitted with acute coronary syndrome or witnessed cardiac arrest

    DEFF Research Database (Denmark)

    Ottesen, Michael Mundt; Dixen, Ulrik; Torp-Pedersen, Christian

    2003-01-01

    OBJECTIVE: To study prehospital behaviour of patients admitted with acute coronary syndrome or witnessed cardiac arrest. DESIGN: Structured interview of 250 consecutive patients with acute coronary syndrome and relatives of 48 patients with witnessed cardiac arrest. The following courses of action...... hundred and thirteen patients (45%) knew of thrombolytic therapy. Twenty-seven of 75 patients with knowledge of the benefit of prompt treatment with thrombolysis, acted in accordance with this awareness. CONCLUSION: Patients misinterpret symptoms of acute coronary syndrome and are misguided when calling...

  20. How Do You Get Your Water? Structural Violence Pedagogy and Women's Access to Water

    Science.gov (United States)

    Keefer, Natalie; Bousalis, Rina

    2015-01-01

    In many parts of the less developed world it is women and girls who are expected to provide water for their family. Frequently, young girls are unable to complete school or get jobs because water scarcity means they are forced to walk miles daily to obtain this most basic need. Since the creation of the United Nations Millennium Goals, progress…

  1. Soft photo structuring of porous silicon in water

    Energy Technology Data Exchange (ETDEWEB)

    Juan, M.; Bouillard, J.S.; Plain, J.; Bachelot, R.; Adam, P.M.; Lerondel, G.; Royer, P. [ICD - Laboratoire de Nanotechnologie et d' Instrumentation Optique, CNRS FRE 2848, Universite de Technologie de Troyes, 12 rue Marie Curie, BP 2060, 10010 Troyes (France)

    2007-05-15

    We report on local photo-induced patterning of porous silicon in water. Scanning probe microscopy images of the sample surface after illumination show that the emission properties as well as the topography are modified according to the interferometric illumination pattern. Local photo-oxidation is believed to be at the origin of these modifications. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Comparison of Novel Carboneous Structures to Treat Nitroaromatic Impacted Water

    Science.gov (United States)

    2015-12-01

    Perfluorinated Compounds from Groundwater using Granular Activated Carbon. University of Colorado. Li, L., Quinlivan, P. A, and Knappe, D. R. U. (2002...and Owens, G. (2009). "Kinetics and thermodynamics of sorption of nitroaromatic compounds to as-grown and oxidized multiwalled carbon nanotubes...used as adsorbents to treat water contaminated by a model nitroaromatic compound , 2,4- dinitrotoluene (DNT). The DNT adsorption capacity of pristine

  3. Structure and Dynamics of Urea/Water Mixtures Investigated by Vibrational Spectroscopy and Molecular Dynamics Simulation

    Science.gov (United States)

    Carr, J. K.; Buchanan, L. E.; Schmidt, J. R.; Zanni, M. T.; Skinner, J. L.

    2013-01-01

    Urea/water is an archetypical “biological” mixture, and is especially well known for its relevance to protein thermodynamics, as urea acts as a protein denaturant at high concentration. This behavior has given rise to an extended debate concerning urea’s influence on water structure. Based on a variety of methods and of definitions of water structure, urea has been variously described as a structure-breaker, a structure-maker, or as remarkably neutral towards water. Because of its sensitivity to microscopic structure and dynamics, vibrational spectroscopy can help resolve these debates. We report experimental and theoretical spectroscopic results for the OD stretch of HOD/H2O/urea mixtures (linear IR, 2DIR, and pump-probe anisotropy decay) and for the CO stretch of urea-D4/D2O mixtures (linear IR only). Theoretical results are obtained using existing approaches for water, and a modification of a frequency map developed for acetamide. All absorption spectra are remarkably insensitive to urea concentration, consistent with the idea that urea only very weakly perturbs water structure. Both this work and experiments by Rezus and Bakker, however, show that water’s rotational dynamics are slowed down by urea. Analysis of the simulations casts doubt on the suggestion that urea immobilizes particular doubly hydrogen bonded water molecules. PMID:23841646

  4. Structure and reactivity in amphiphile-water micelles

    International Nuclear Information System (INIS)

    Chevalier, Yves

    1985-01-01

    Following a review of the general properties of micelles, this report contains two parts: - A structural study of octylphosphate micelles. Important structural changes have been evidenced by mean of small angle neutron scattering as the electrical charge of the interface is varied. The NMR relaxation study of the conformation of the hydrocarbon chains has shown that the micellar core is disordered in contrast with the interface which is rather structured. The diffusion motions in the interface and the segmental motions of the chains are fast. - Studies on the reactivity in micelles have been carried out. A large micellar effect on the complexation of transition ions by amphiphilic ligands is evidenced. The problem of solute localization in micelles is developed with few examples. (author) [fr

  5. Out-of-hospital cardiac arrest

    DEFF Research Database (Denmark)

    Sondergaard, Kathrine B; Hansen, Steen Moller; Pallisgaard, Jannik L

    2018-01-01

    AIMS: Despite wide dissemination of automated external defibrillators (AEDs), bystander defibrillation rates remain low. We aimed to investigate how route distance to the nearest accessible AED was associated with probability of bystander defibrillation in public and residential locations. METHODS......: We used data from the nationwide Danish Cardiac Arrest Registry and the Danish AED Network to identify out-of-hospital cardiac arrests and route distances to nearest accessible registered AED during 2008-2013. The association between route distance and bystander defibrillation was described using...... in public locations, the probability of bystander defibrillation at 0, 100 and 200meters from the nearest AED was 35.7% (95% confidence interval 28.0%-43.5%), 21.3% (95% confidence interval 17.4%-25.2%), and 13.7% (95% confidence interval 10.1%-16.8%), respectively. The corresponding numbers for cardiac...

  6. HSST crack-arrest studies overview

    International Nuclear Information System (INIS)

    Pugh, C.E.; Whitman, G.D.

    1985-01-01

    An overview is given of the efforts underway in the Heavy-Section Steel Technology (HSST) Program to better understand and model crack-arrest behavior in reactor pressure vessel steels. The efforts are both experimental and analytical. The experimental work provides K/sub Ia/ data from laboratory-sized specimens, from thick-wall cylinders which exhibit essentially-full restraint and from nonisothermal wide-plate specimens. These data serve to define toughness-temperature trends and to provide validation data under prototypical reactor conditions. The analytical efforts interpret and correlate the data, plus provide LEFM, elastodynamic and viscoplastic methods for analyzing crack run-arrest behavior in reactor vessels. The analysis methods are incorporated into finite element computer programs which are under development at three separate laboratories. 22 refs., 10 figs

  7. Dental Calculus Arrest of Dental Caries.

    Science.gov (United States)

    Keyes, Paul H; Rams, Thomas E

    An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. These observations further document the potential protective effects of dental calculus mineralization against dental caries.

  8. Dental Calculus Arrest of Dental Caries

    Science.gov (United States)

    Keyes, Paul H.; Rams, Thomas E.

    2016-01-01

    Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. Materials and methods A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Results Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. Conclusions These observations further document the potential protective effects of dental calculus mineralization against dental caries. PMID:27446993

  9. Impact of soda-lime borosilicate glass composition on water penetration and water structure at the first time of alteration

    International Nuclear Information System (INIS)

    Rebiscoul, D.; Bruguier, F.; Gin, S.; Magnin, V.

    2012-01-01

    In this study, the impact of soda-lime borosilicate glass composition and particularly the effect of charge compensators such Ca and Na and, of network formers such Si and Zr, on water penetration and water structure at the first time of alteration were investigated. Two non-destructive techniques were combined: the Fourier transform infrared spectroscopy in attenuated total reflection geometry to precise the predominant alteration mechanisms and assess the water structure in altered zone and the grazing incidence X-ray reflectometry to determine the thickness of the altered glass zone allowing to calculate the water diffusion coefficients through the glasses. The results of glass alteration at pH = 3 and 30 degrees C have shown that hydrolysis was the predominant mechanism after few seconds for glass having a high amount of non-binding oxygen. For the other glasses, which for the diffusion was the limiting reaction, the calculated water diffusion coefficients were comprised between 10 -21 and 10 -19 m 2 .s -1 and vary as a function of glass composition. An activation energy of 76.9 kJ.mol -1 was calculated and appears to be higher than inert gas diffusion through the glass highlighting that water molecules strongly interact with the glass matrix. (authors)

  10. Water balance and topography predict fire and forest structure patterns

    Science.gov (United States)

    Van R. Kane; James A. Lutz; C. Alina Cansler; Nicholas A. Povak; Derek J. Churchill; Douglas F. Smith; Jonathan T. Kane; Malcolm P. North

    2015-01-01

    Mountainous topography creates fine-scale environmental mosaics that vary in precipitation, temperature, insolation, and slope position. This mosaic in turn influences fuel accumulation and moisture and forest structure. We studied these the effects of varying environmental conditions across a 27,104 ha landscape within Yosemite National Park, California, USA, on the...

  11. Electronic structure effects in liquid water studied by photoelectron spectroscopy and density functional theory

    Energy Technology Data Exchange (ETDEWEB)

    Nordlund, Dennis; Odelius, Michael; Bluhm, Hendrik; Ogasawara, Hirohito; Pettersson, Lars G.M.; Nilsson, Anders

    2008-04-29

    We present valence photoelectron emission spectra of liquid water in comparison with gas-phase water, ice close to the melting point, low temperature amorphous and crystalline ice. All aggregation states have major electronic structure changes relative to the free molecule, with rehybridization and development of bonding and anti-bonding states accompanying the hydrogen bond formation. Sensitivity to the local structural order, most prominent in the shape and splitting of the occupied 3a{sub 1} orbital, is understood from the electronic structure averaging over various geometrical structures, and reflects the local nature of the orbital interaction.

  12. Structural integrity of water reactor pressure boundary components

    International Nuclear Information System (INIS)

    Loss, F.J.

    1977-01-01

    The dynamic fracture toughness was determined as a function of temperature for three-point bend specimens of A533-B, A508-2, and A302-B steels. Crack propagation rates at 288 0 C in a water reactor environment were determined for A533-B and A508-2. Radiation-induced degradation of notch toughness of reactor steels and welds was explored. The ''warm prestress'' occurring in a flawed reactor vessel following a LOCA and operation of ECCS was studied. 25 figures

  13. Seismic evaluation of a cooling water reservoir facility including fluid-structure and soil-structure interaction effects

    International Nuclear Information System (INIS)

    Kabir, A.F.; Maryak, M.E.

    1991-01-01

    Seismic analyses and structural evaluations were performed for a cooling water reservoir of a nuclear reactor facility. The horizontal input seismic motion was the NRC Reg. guide 1.60 spectrum shape anchored at 0.20g zero period acceleration. Vertical input was taken as two-thirds of the horizontal input. Soil structure interaction and hydrodynamic effects were addressed in the seismic analyses. Uncertainties in the soil properties were accounted for by considering three soil profiles. Two 2-dimensional SSI models and a 3-dimensional static model. Representing different areas of the reservoir structures were developed and analyzed to obtain seismic forces and moments, and accelerations at various locations. The results included in this paper indicated that both hydrodynamic and soil-structure interaction effects are significant contributors to the seismic responses of the water-retaining walls of the reservoir

  14. Lower Colorado River GRP Dams and Water Retention Structures, Arizona, 2012, Arizona Department of Environmental Quality

    Data.gov (United States)

    U.S. Environmental Protection Agency — Location of dams and water retention structures as compiled from multiple sources by the Arizona Department of Environmental Quality (ADEQ). The data are "sensitive"...

  15. Seasonal and diurnal variability of thermal structure in the coastal waters off Visakhapatnam

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, B.P.; RameshBabu, V.; Chandramohan, P.

    relaxing event helps in the development of a strong layered thermal structure while convective mixing due to winter inversions during November to February causes weak thermal gradients in the water column...

  16. Structure from Dynamics: Vibrational Dynamics of Interfacial Water as a Probe of Aqueous Heterogeneity

    Science.gov (United States)

    2018-01-01

    The structural heterogeneity of water at various interfaces can be revealed by time-resolved sum-frequency generation spectroscopy. The vibrational dynamics of the O–H stretch vibration of interfacial water can reflect structural variations. Specifically, the vibrational lifetime is typically found to increase with increasing frequency of the O–H stretch vibration, which can report on the hydrogen-bonding heterogeneity of water. We compare and contrast vibrational dynamics of water in contact with various surfaces, including vapor, biomolecules, and solid interfaces. The results reveal that variations in the vibrational lifetime with vibrational frequency are very typical, and can frequently be accounted for by the bulk-like heterogeneous response of interfacial water. Specific interfaces exist, however, for which the behavior is less straightforward. These insights into the heterogeneity of interfacial water thus obtained contribute to a better understanding of complex phenomena taking place at aqueous interfaces, such as photocatalytic reactions and protein folding. PMID:29490138

  17. Light Water Reactor Sustainability Program Advanced Seismic Soil Structure Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Bolisetti, Chandrakanth [Idaho National Lab. (INL), Idaho Falls, ID (United States); Coleman, Justin Leigh [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-06-01

    Risk calculations should focus on providing best estimate results, and associated insights, for evaluation and decision-making. Specifically, seismic probabilistic risk assessments (SPRAs) are intended to provide best estimates of the various combinations of structural and equipment failures that can lead to a seismic induced core damage event. However, in some instances the current SPRA approach has large uncertainties, and potentially masks other important events (for instance, it was not the seismic motions that caused the Fukushima core melt events, but the tsunami ingress into the facility). SPRA’s are performed by convolving the seismic hazard (this is the estimate of all likely damaging earthquakes at the site of interest) with the seismic fragility (the conditional probability of failure of a structure, system, or component given the occurrence of earthquake ground motion). In this calculation, there are three main pieces to seismic risk quantification, 1) seismic hazard and nuclear power plants (NPPs) response to the hazard, 2) fragility or capacity of structures, systems and components (SSC), and 3) systems analysis. Two areas where NLSSI effects may be important in SPRA calculations are, 1) when calculating in-structure response at the area of interest, and 2) calculation of seismic fragilities (current fragility calculations assume a lognormal distribution for probability of failure of components). Some important effects when using NLSSI in the SPRA calculation process include, 1) gapping and sliding, 2) inclined seismic waves coupled with gapping and sliding of foundations atop soil, 3) inclined seismic waves coupled with gapping and sliding of deeply embedded structures, 4) soil dilatancy, 5) soil liquefaction, 6) surface waves, 7) buoyancy, 8) concrete cracking and 9) seismic isolation The focus of the research task presented here-in is on implementation of NLSSI into the SPRA calculation process when calculating in-structure response at the area

  18. Method of repairing incore structure and water sealing chamber

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Toshikazu; Sato, Sukenobu (Hitachi Nuclear Engineering Co. Ltd., Ibaraki (Japan)); Wada, Noriaki; Kurosawa, Koichi; Tsujimura, Hiroshi; Enomoto, Kunio.

    1993-11-26

    An incore-chamber main body comprises a guide tube, an insertion guide, an extensible arm, a device fixing mechanism, a gas supply pipe, a guide driving mechanism and an in-core chamber control device. The in-core chamber main body is installed and secured to an upper flange surface of a shroud. Reactor water is raised to a level below a flange of a reactor pressure vessel while supplying a dry gas from a gas supply pipe to make the inside of the shroud as a gas atmosphere. Subsequently, each of the devices is attached to the top end of the extensible arm, and the guide driving mechanism is operated by the in-core chamber control device to an aimed position for preventive maintenance or repair to conduct positioning and fixing by utilizing the guide tube and the insertion guide. This enables to conduct preventive maintenance or repair in a state where reactor water is present to the outside of the in-core reactor chamber while maintaining the in-core equipment in the gas atmosphere, thereby enabling to reduce operator's exposure dose. (I.N.).

  19. Method of repairing incore structure and water sealing chamber

    International Nuclear Information System (INIS)

    Kikuchi, Toshikazu; Sato, Sukenobu; Wada, Noriaki; Kurosawa, Koichi; Tsujimura, Hiroshi; Enomoto, Kunio.

    1993-01-01

    An incore-chamber main body comprises a guide tube, an insertion guide, an extensible arm, a device fixing mechanism, a gas supply pipe, a guide driving mechanism and an in-core chamber control device. The in-core chamber main body is installed and secured to an upper flange surface of a shroud. Reactor water is raised to a level below a flange of a reactor pressure vessel while supplying a dry gas from a gas supply pipe to make the inside of the shroud as a gas atmosphere. Subsequently, each of the devices is attached to the top end of the extensible arm, and the guide driving mechanism is operated by the in-core chamber control device to an aimed position for preventive maintenance or repair to conduct positioning and fixing by utilizing the guide tube and the insertion guide. This enables to conduct preventive maintenance or repair in a state where reactor water is present to the outside of the in-core reactor chamber while maintaining the in-core equipment in the gas atmosphere, thereby enabling to reduce operator's exposure dose. (I.N.)

  20. The Relationship Between Dynamics and Structure in the Far Infrared Absorption Spectrum of Liquid Water

    Energy Technology Data Exchange (ETDEWEB)

    Woods, K.

    2005-01-14

    Using an intense source of far-infrared radiation, the absorption spectrum of liquid water is measured at a temperature ranging from 269 to 323 K. In the infrared spectrum we observe modes that are related to the local structure of liquid water. Here we present a FIR measured spectrum that is sensitive to the low frequency (< 100cm{sup -1}) microscopic details that exist in liquid water.

  1. Utilization threshold of surface water and groundwater based on the system optimization of crop planting structure

    Directory of Open Access Journals (Sweden)

    Qiang FU,Jiahong LI,Tianxiao LI,Dong LIU,Song CUI

    2016-09-01

    Full Text Available Based on the diversity of the agricultural system, this research calculates the planting structures of rice, maize and soybean considering the optimal economic-social-ecological aspects. Then, based on the uncertainty and randomness of the water resources system, the interval two-stage stochastic programming method, which introduces the uncertainty of the interval number, is used to calculate the groundwater exploitation and the use efficiency of surface water. The method considers the minimum cost of water as the objective of the uncertainty model for surface water and groundwater joint scheduling optimization for different planting structures. Finally, by calculating harmonious entropy, the optimal exploitation utilization interval of surface water and groundwater is determined for optimal cultivation in the Sanjiang Plain. The optimal matching of the planting structure under the economic system is suitable when the mining ratio of the surface is in 44.13%—45.45% and the exploitation utilization of groundwater is in 54.82%—66.86%, the optimal planting structure under the social system is suitable when surface water mining ratio is in 47.84%—48.04% and the groundwater exploitation threshold is in 67.07%—72.00%. This article optimizes the economic-social-ecological-water system, which is important for the development of a water- and food-conserving society and providing a more accurate management environment.

  2. Structure and thermal analysis of the water cooling mask at NSRL front end

    International Nuclear Information System (INIS)

    Zhao Feiyun; Xu Chaoyin; Wang Qiuping; Wang Naxiu

    2003-01-01

    A water cooling mask is an important part of the front end, usually used for absorbing high power density synchrotron radiation to protect the apparatus from being destroyed by heat load. This paper presents the structure of the water cooling mask and the thermal analysis results of the mask block at NSRL using Program ANSYS5.5

  3. Structural investigation of water-soluble polysaccharides extracted from the fruit bodies of Coprinus comatus

    NARCIS (Netherlands)

    Li, Bo; Dobruchowska, Justyna M.; Gerwig, Gerrit J.; Dijkhuizen, Lubbert; Kamerling, Johannis P.

    2013-01-01

    Water-soluble polysaccharide material, extracted from the stipes of the fruit bodies of Coprinus comatus by hot water, was fractionated by sequential weak anion-exchange and size-exclusion chromatography. The relevant fractions were subjected to structural analysis, including (D/L)

  4. Structural transition in a lipid-water liquid system

    International Nuclear Information System (INIS)

    Bulavin, L.A.; Solovjov, D.V.; Solovjov, D.V.; Gorshkova, Yu.Je.; Zhigunov, O.M.; Ivan'kov, O.I.; Ivan'kov, O.I.; Gordelij, V.I.; Gordelij, V.I.; Gordelij, V.I.; Gordelij, V.I.; Kuklin, O.I.; Kuklin, O.I.

    2012-01-01

    Small-angle X-ray scattering technique has been used to study multilayer lipid membranes of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and the 3:1-mixture DPPC/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) in excess water. The temperature dependences of the repetition period for lipid bilayers in the temperature range 20-55 o C are obtained. A comparative analysis of the scattering curves obtained for multilayer membranes showed that, below a temperature of 40 o C , there emerges an additional ordering with a repetition period of 66 A in the lipid mixture, which we associate with the lipid phase separation. A disappearance of the so-called ripple (wave-like) phase of DPPC lipid in the mixture is also observed.

  5. Structural and dynamical properties of water confined between two hydrophilic surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Di Napoli, Solange, E-mail: dinapoli@tandar.cnea.gov.a [Depto. de Fisica - CAC, Comision Nacional de Energia Atomica, Av. Gral Paz 1499, (1650) San Martin, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (Argentina); Gamba, Zulema, E-mail: gamba@tandar.cnea.gov.a [Depto. de Fisica - CAC, Comision Nacional de Energia Atomica, Av. Gral Paz 1499, (1650) San Martin, Buenos Aires (Argentina)

    2009-10-01

    The properties of water in the vicinity of surfaces and under confinement have been extensively studied because of the relevance of a quantitative understanding of many processes that not only take place in biological systems, like cells, membranes and microemulsions, but also in many others such as confined water in rocks, ionic channels and interestellar matter. In this work we perform molecular dynamic calculations of the nanoscopic structure of TIP5P model water confined between two hydrophilic surfaces. We calculate the diffusion coefficients and the atomic density profile of water molecules and polar ions in the system as a function of the number of water molecules per amphiphilic (n{sub W}). We also study the dependence of the water layer thickness and the profiles of water dipole orientation with this parameter.

  6. Structural and dynamical properties of water confined between two hydrophilic surfaces

    International Nuclear Information System (INIS)

    Di Napoli, Solange; Gamba, Zulema

    2009-01-01

    The properties of water in the vicinity of surfaces and under confinement have been extensively studied because of the relevance of a quantitative understanding of many processes that not only take place in biological systems, like cells, membranes and microemulsions, but also in many others such as confined water in rocks, ionic channels and interestellar matter. In this work we perform molecular dynamic calculations of the nanoscopic structure of TIP5P model water confined between two hydrophilic surfaces. We calculate the diffusion coefficients and the atomic density profile of water molecules and polar ions in the system as a function of the number of water molecules per amphiphilic (n W ). We also study the dependence of the water layer thickness and the profiles of water dipole orientation with this parameter.

  7. Distinct mechanisms act in concert to mediate cell cycle arrest.

    Science.gov (United States)

    Toettcher, Jared E; Loewer, Alexander; Ostheimer, Gerard J; Yaffe, Michael B; Tidor, Bruce; Lahav, Galit

    2009-01-20

    In response to DNA damage, cells arrest at specific stages in the cell cycle. This arrest must fulfill at least 3 requirements: it must be activated promptly; it must be sustained as long as damage is present to prevent loss of genomic information; and after the arrest, cells must re-enter into the appropriate cell cycle phase to ensure proper ploidy. Multiple molecular mechanisms capable of arresting the cell cycle have been identified in mammalian cells; however, it is unknown whether each mechanism meets all 3 requirements or whether they act together to confer specific functions to the arrest. To address this question, we integrated mathematical models describing the cell cycle and the DNA damage signaling networks and tested the contributions of each mechanism to cell cycle arrest and re-entry. Predictions from this model were then tested with quantitative experiments to identify the combined action of arrest mechanisms in irradiated cells. We find that different arrest mechanisms serve indispensable roles in the proper cellular response to DNA damage over time: p53-independent cyclin inactivation confers immediate arrest, whereas p53-dependent cyclin downregulation allows this arrest to be sustained. Additionally, p21-mediated inhibition of cyclin-dependent kinase activity is indispensable for preventing improper cell cycle re-entry and endoreduplication. This work shows that in a complex signaling network, seemingly redundant mechanisms, acting in a concerted fashion, can achieve a specific cellular outcome.

  8. Novel Structures for the Excess Electron State of the Water Hexamer and the Interaction Forces Governing the Structures

    International Nuclear Information System (INIS)

    Lee, S.; Kim, J.; Lee, S.J.; Kim, K.S.

    1997-01-01

    The geometrical and electronic structures of partially hydrated electron systems, in particular, the water hexamer, which have been controversial for decades, have been clarified by an exhaustive search for possible low-lying energy structures. Several competing interaction forces governing the conformation have been examined for the first time. The low-lying energy structures are hybrid (or partially internal and partially surface) excess electron states. Our prediction is evidenced from excellent agreements with available experimental data. The vertical electron-detachment energies are mainly determined by the number of dangling H atoms (H d ) . copyright 1997 The American Physical Society

  9. Structures of nanoparticles prepared from oil-in-water emulsions.

    Science.gov (United States)

    Sjöström, B; Kaplun, A; Talmon, Y; Cabane, B

    1995-01-01

    Hydrophobic substances were dissolved in an organic solvent and emulsified with an aqueous solution at very high shear. Droplets of very small sizes (50-100 nm) were obtained by using surfactants which were combinations of lecithins and bile salts. After emulsification, the organic solvent was removed by evaporation, yielding stable dispersions of solid particles. The sizes, shapes, and structures of the particles were examined through quasi-elastic light scattering, small-angle neutron scattering and cryotransmission electron microscopy. Cholesterol acetate particles stabilized by lecithin and bile salts were found to be platelets of 10-20 nm thickness and 80 nm diameter. Cholesteryl acetate particles stabilized with POE-(20)-sorbitan monolaurate were dense spherical globules of diameter 100 nm. Particles with a composition similar to the endogenously occurring, lipoprotein, LDL, were large spherical globules studded with small vesicles. The subsequent evolution of the cholesteryl acetate dispersion upon aging was examined. There was no transfer of cholesteryl acetate between particles nor to large crystals. However, some aggregation of the particles was observed when the volume fraction of the particles in the aqueous dispersion exceeded 0.05. Thus, the structure of the nanoparticles obtained through deswelling of emulsion droplets changes according to the nature of the emulsifiers and to the composition of the hydrophobic substances which they contain.

  10. Accurate Energies and Structures for Large Water Clusters Using the X3LYP Hybrid Density Functional

    OpenAIRE

    Su, Julius T.; Xu, Xin; Goddard, William A., III

    2004-01-01

    We predict structures and energies of water clusters containing up to 19 waters with X3LYP, an extended hybrid density functional designed to describe noncovalently bound systems as accurately as covalent systems. Our work establishes X3LYP as the most practical ab initio method today for calculating accurate water cluster structures and energies. We compare X3LYP/aug-cc-pVTZ energies to the most accurate theoretical values available (n = 2−6, 8), MP2 with basis set superposition error (BSSE)...

  11. Integrating Water, Actors, and Structure to Study Socio-Hydro-Ecological Systems

    Science.gov (United States)

    Hale, R. L.; Armstrong, A.; Baker, M. A.; Bedingfield, S.; Betts, D.; Buahin, C. A.; Buchert, M.; Crowl, T.; Dupont, R.; Endter-Wada, J.; Flint, C.; Grant, J.; Hinners, S.; Horns, D.; Horsburgh, J. S.; Jackson-Smith, D.; Jones, A. S.; Licon, C.; Null, S. E.; Odame, A.; Pataki, D. E.; Rosenberg, D. E.; Runburg, M.; Stoker, P.; Strong, C.

    2014-12-01

    Urbanization, climate uncertainty, and ecosystem change represent major challenges for managing water resources. Water systems and the forces acting upon them are complex, and there is a need to understand and generically represent the most important system components and linkages. We developed a framework to facilitate understanding of water systems including potential vulnerabilities and opportunities for sustainability. Our goal was to produce an interdisciplinary framework for water resources research to address water issues across scales (e.g., city to region) and domains (e.g., water supply and quality, urban and transitioning landscapes). An interdisciplinary project (iUTAH - innovative Urban Transitions and Aridregion Hydro-sustainability) with a large (N=~100), diverse team having expertise spanning the hydrologic, biological, ecological, engineering, social, planning, and policy sciences motivated the development of this framework. The framework was developed through review of the literature, meetings with individual researchers, and workshops with participants. The Structure-Water-Actor Framework (SWAF) includes three main components: water (quality and quantity), structure (natural, built, and social), and actors (individual and organizational). Key linkages include: 1) ecological and hydrological processes, 2) ecosystem and geomorphic change, 3) planning, design, and policy, 4) perceptions, information, and experience, 5) resource access, and 6) operational water use and management. Our expansive view of structure includes natural, built, and social components, allowing us to examine a broad set of tools and levers for water managers and decision-makers to affect system sustainability and understand system outcomes. We validate the SWAF and illustrate its flexibility to generate insights for three research and management problems: green stormwater infrastructure in an arid environment, regional water supply and demand, and urban river restoration

  12. An ex vivo study of arrested primary teeth caries with silver diamine fluoride therapy.

    Science.gov (United States)

    Mei, May L; Ito, L; Cao, Y; Lo, Edward C M; Li, Q L; Chu, C H

    2014-04-01

    This ex vivo study compared the physico-chemical structural differences between primary carious teeth biannually treated with silver diamine fluoride (SDF) and carious teeth without such treatment. Twelve carious primary upper-central incisors were collected from 6-year-old children. Six teeth had arrested caries after 24-month biannual SDF applications and 6 had active caries when there was no topical fluoride treatment. The mineral density, elemental contents, surface morphology, and crystal characteristics were assessed by micro-computed tomography (micro-CT), energy-dispersive X-ray spectrometry (EDX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Micro-CT examination revealed a superficial opaque band approximately 150μm on the arrested cavitated dentinal lesion. This band was limited in the active carious lesion. EDX examination detected a higher intensity of calcium and phosphate of 150μm in the surface zone than in the inner zone, but this zone was restricted in the active cavitated dentinal lesion. SEM examination indicated that the collagens were protected from being exposed in the arrested cavitated dentinal lesion, but were exposed in the active cavitated dentinal lesion. TEM examination suggested that remineralised hydroxyapatites were well aligned in the arrested cavitated dentinal lesion, while those in the active cavitated dentinal lesion indicated a random apatite arrangement. A highly remineralised zone rich in calcium and phosphate was found on the arrested cavitated dentinal lesion of primary teeth with an SDF application. The collagens were protected from being exposed in the arrested cavitated dentinal lesion. Clinical SDF application positively influences dentine remineralisation. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Fluid-structure interaction with pipe-wall viscoelasticity during water hammer

    NARCIS (Netherlands)

    Keramat, A.; Tijsseling, A.S.; Hou, Q.; Ahmadi, A.

    2011-01-01

    Fluid-structure interaction (FSI) due to water hammer in a pipeline which has viscoelastic wall behaviour is studied. Appropriate governing equations are derived and numerically solved. In the numerical implementation of the hydraulic and structural equations, viscoelasticity is incorporated using

  14. Fluid-structure interaction with pipe-wall viscoelasticity during water hammer

    NARCIS (Netherlands)

    Keramat, A.; Tijsseling, A.S.; Hou, Q.; Ahmadi, A.

    2012-01-01

    Fluid–structure interaction (FSI) due to water hammer in a pipeline which has viscoelastic wall behaviour is studied. Appropriate governing equations are derived and numerically solved. In the numerical implementation of the hydraulic and structural equations, viscoelasticity is incorporated using

  15. Spectral structure of mesoscale winds over the water

    DEFF Research Database (Denmark)

    Larsén, Xiaoli Guo; Vincent, Claire Louise; Larsen, Søren Ejling

    2013-01-01

    to describe the spectral slope transition as well as the limit for application of the Taylor hypothesis. The stability parameter calculated from point measurements, the bulk Richardson number, is found insufficient to represent the various atmospheric structures that have their own spectral behaviours under...... spectra show universal characteristics, in agreement with the findings in literature, including the energy amplitude and the −5/3 spectral slope in the mesoscale range transitioning to a slope of −3 for synoptic and planetary scales. The integral time-scale of the local weather is found to be useful...... different stability conditions, such as open cells and gravity waves. For stationary conditions, the mesoscale turbulence is found to bear some characteristics of two-dimensional isotropy, including (1) very minor vertical variation of spectra; (2) similar spectral behaviour for the along- and across...

  16. [Mass maritime casualty incidents in German waters: structures and resources].

    Science.gov (United States)

    Castan, J; Paschen, H-R; Wirtz, S; Dörges, V; Wenderoth, S; Peters, J; Blunk, Y; Bielstein, A; Kerner, T

    2012-07-01

    The Central Command for Maritime Emergencies was founded in Germany in 2003 triggered by the fire on board of the cargo ship "Pallas" in 1998. Its mission is to coordinate and direct measures at or above state level in maritime emergency situations in the North Sea and the Baltic Sea. A special task in this case is to provide firefighting and medical care. To face these challenges at sea emergency doctors and firemen have been specially trained. This form of organization provides a concept to counter mass casualty incidents and peril situations at sea. Since the foundation of the Central Command for Maritime Emergencies there have been 5 operations for firefighting units and 4 for medical response teams. Assignments and structure of the Central Command for Maritime Emergencies are unique in Europe.

  17. Mechanics of structures and maintenance of pressurized water reactors

    International Nuclear Information System (INIS)

    Hutin, J.P.

    1992-01-01

    Electricite de France nowadays has in operation 34 units of 900 MW and 17 units of 1300 MW of PWR. Since the first unit was run, this means that more than 350 reactor-years have been performed, to which should be added the experience already gained on fossil fuel or natural uranium plants. This enabled EDF to build its own philosophy and a strategy for maintenance that are best suited for the specific requirements of the hardware with which the actual nuclear boilers are made-up. This philosophy and strategy rest upon an analysis which calls widely for the mechanics of structures, to such an extent that major decisions concerning maintenance depend on the ability that one has for resolving problems within the scope of that discipline

  18. Structure of electron tracks in water. 2. Distribution of primary ionizations and excitations in water radiolysis

    International Nuclear Information System (INIS)

    Pimblott, S.M.; Mozumder, A.

    1991-01-01

    A procedure for the calculation of entity-specific ionization and excitation probabilities for water radiolysis at low linear energy transfer (LET) has been developed. The technique pays due attention to the effects of the ionization threshold and the energy dependence of the ionization efficiency. The numbers of primary ionizations and excitations are not directly proportional to the spur energy. At a given spur energy, ionization follows a binomial distribution subject to an energetically possible maximum. The excitation distribution for a spur of given energy and with a given number of ionizations is given by a geometric series. The occurrence probabilities depend upon the cross sections of ionization, excitation, and other inferior processes. Following the low-LET radiolysis of liquid water the most probable spurs contain one ionization, two ionizations, or one ionization and one excitation, while in water vapor they contain either one ionization or one excitation. In liquid water the most probable outcomes for spurs corresponding to the most probable energy loss (22 eV) and to the mean energy loss (38 eV) are one ionization and one excitation, and two ionizations and one excitation, respectively. In the vapor, the most probable energy loss is 14 eV which results in one ionization or one excitation and the mean energy loss is 34 eV for which the spur of maximum probability contains one ionization and two excitations. The total calculated primary yields for low-LET radiolysis are in approximate agreement with experiment in both phases

  19. Centralized Drinking Water Treatment Operations Shape Bacterial and Fungal Community Structure.

    Science.gov (United States)

    Ma, Xiao; Vikram, Amit; Casson, Leonard; Bibby, Kyle

    2017-07-05

    Drinking water microbial communities impact opportunistic pathogen colonization and corrosion of water distribution systems, and centralized drinking water treatment represents a potential control for microbial community structure in finished drinking water. In this article, we examine bacterial and fungal abundance and diversity, as well as the microbial community taxonomic structure following each unit operation in a conventional surface water treatment plant. Treatment operations drove the microbial composition more strongly than sampling time. Both bacterial and fungal abundance and diversity decreased following sedimentation and filtration; however, only bacterial abundance and diversity was significantly impacted by free chlorine disinfection. Similarly, each treatment step was found to shift bacterial and fungal community beta-diversity, with the exception of disinfection on the fungal community structure. We observed the enrichment of bacterial and fungal taxa commonly found in drinking water distribution systems through the treatment process, for example, Sphingomonas following filtration and Leptospirillium and Penicillium following disinfection. Study results suggest that centralized drinking water treatment processes shape the final drinking water microbial community via selection of community members and that the bacterial community is primarily driven by disinfection while the eukaryotic community is primarily controlled by physical treatment processes.

  20. Effect of Water-Cement Ratio on Pore Structure and Strength of Foam Concrete

    Directory of Open Access Journals (Sweden)

    Zhongwei Liu

    2016-01-01

    Full Text Available Foam concrete with different dry densities (400, 500, 600, 700, and 800 kg/m3 was prepared from ordinary Portland cement (P.O.42.5R and vegetable protein foaming agent by adjusting the water-cement ratio through the physical foaming method. The performance of the cement paste adopted, as well as the structure and distribution of air pores, was characterized by a rheometer, scanning electron microscope, vacuum water saturation instrument, and image analysis software. Effects of the water-cement ratio on the relative viscosity of the cement paste, as well as pore structure and strength of the hardened foam concrete, were discussed. Results showed that water-cement ratio can influence the size, distribution, and connectivity of pores in foam concrete. The compressive strength of the foam concrete showed an inverted V-shaped variation law with the increase in water-cement ratio.

  1. Structure and dynamics in liquid water from x-ray absorption spectroscopy

    International Nuclear Information System (INIS)

    Wernet, Philippe

    2009-01-01

    Oxygen K-edge x-ray absorption spectra of water are discussed. The spectra of gas-phase water, liquid water and ice illustrate the sensitivity of oxygen K-edge x-ray absorption spectroscopy to hydrogen bonding in water. Transmission mode spectra of amorphous and crystalline ice are compared to x-ray Raman spectra of ice. The good agreement consolidates the experimental spectrum of crystalline ice and represents an incentive for theoretical calculations of the oxygen K-edge absorption spectrum of crystalline ice. Time-resolved infrared-pump and x-ray absorption probe results are finally discussed in the light of this structural interpretation.

  2. Probing membrane protein structure using water polarization transfer solid-state NMR.

    Science.gov (United States)

    Williams, Jonathan K; Hong, Mei

    2014-10-01

    Water plays an essential role in the structure and function of proteins, lipid membranes and other biological macromolecules. Solid-state NMR heteronuclear-detected (1)H polarization transfer from water to biomolecules is a versatile approach for studying water-protein, water-membrane, and water-carbohydrate interactions in biology. We review radiofrequency pulse sequences for measuring water polarization transfer to biomolecules, the mechanisms of polarization transfer, and the application of this method to various biological systems. Three polarization transfer mechanisms, chemical exchange, spin diffusion and NOE, manifest themselves at different temperatures, magic-angle-spinning frequencies, and pulse irradiations. Chemical exchange is ubiquitous in all systems examined so far, and spin diffusion plays the key role in polarization transfer within the macromolecule. Tightly bound water molecules with long residence times are rare in proteins at ambient temperature. The water polarization-transfer technique has been used to study the hydration of microcrystalline proteins, lipid membranes, and plant cell wall polysaccharides, and to derive atomic-resolution details of the kinetics and mechanism of ion conduction in channels and pumps. Using this approach, we have measured the water polarization transfer to the transmembrane domain of the influenza M2 protein to obtain information on the structure of this tetrameric proton channel. At short mixing times, the polarization transfer rates are site-specific and depend on the pH, labile protons, sidechain conformation, as well as the radial position of the residues in this four-helix bundle. Despite the multiple dependences, the initial transfer rates reflect the periodic nature of the residue positions from the water-filled pore, thus this technique provides a way of gleaning secondary structure information, helix tilt angle, and the oligomeric structure of membrane proteins. Copyright © 2014 Elsevier Inc. All

  3. Characterisation of fluid-structure interaction for water impact of composite panels

    Directory of Open Access Journals (Sweden)

    M Battley

    2016-09-01

    Full Text Available Hydrodynamic loads can be very significant for high performance marine vessels. Water impact of panels, known as "slamming", typically generates high magnitude short duration pressure pulses that move across the structure. In the case of compliant panels there can be significant coupling between the pressures and the structural responses. While there has been significant development of numerical methods to simulate this type of fluid-structure interaction there is only very limited experimental data available for validation of the simulation approaches. This paper describes an experimental study of sandwich composite panels subjected to water slamming impacts. The results demonstrate that compliant panels subjected to water slamming impacts experience different pressures than rigid panels, and have different structural responses than predicted by traditional uniform pressure based analysis approaches. The study also characterizes the significant effects that the dimensions of pressure transducers and data acquisition sampling rates have on the measured pressures.

  4. Uncommon structure making/breaking behaviour of cholinium taurate in water

    International Nuclear Information System (INIS)

    Gadžurić, Slobodan; Tot, Aleksandar; Armaković, Stevan; Armaković, Sanja; Panić, Jovana; Jović, Branislav; Vraneš, Milan

    2017-01-01

    Highlights: • Structuring of water in cholinium taurate ionic liquids was studied. • Nature of interactions were discussed. • Structure breaking properties were observed below and structure making properties above 300 K. • Molecular dynamics confirmed conclusions derived from experiments. - Abstract: Synthesis, volumetric and transport properties of the new third generation ionic liquid cholinium taurate, [Chol][Tau], are reported. Density, viscosity and electrical conductivity measurements of diluted aqueous solution of [Chol][Tau] were performed, while from the theoretical aspects density functional theory (DFT) calculations and molecular dynamics (MD) simulations have been applied in order to understand the nature of interactions and water structuring in the studied system. DFT approach was used to understand geometry and non-covalent interactions between [Chol] + and [Tau] − ions, while radial distribution functions (RDFs) obtained after MD simulations were applied in order to determine the parts of the ionic liquid that are most responsible for the interaction with water.

  5. Comparison of water degradation of YBaCuO superconducting films made from different structures

    International Nuclear Information System (INIS)

    Chang, C.; Tsai, J.A.

    1988-01-01

    Immersion of YBaCuO superconducting films in water has shown a large difference in degradation between structures with and without silver. For the structures containing silver layers and depositing at a high temperature, superconducting films with zero resistance at 87 K remain superconductive at 77 K after 5 h immersion in water, with an increase in room-temperature film resistance by a factor of 4; the contact resistance remains low after 60 h of immersion, allowing the measurement at low temperatures. For the structures containing no silver and depositing at room temperature, the contact resistance rapidly increases with immersion times, making the measurement at 77 K difficult after 5 min of immersion. Changes in the sharpness of the superconductive transition, and structures of the films due to the water immersion are also compared

  6. New potentional of high-speed water jet technology for renovating concrete structures

    Science.gov (United States)

    Bodnárová, L.; Sitek, L.; Hela, R.; Foldyna, J.

    2011-06-01

    The paper discusses the background and results of research focused on the action of a high-speed water jet on concrete with different qualities. The sufficient and careful removal of degraded concrete layers is very important for the renovation of concrete structures. High-speed water jet technology is one of the most common methods used for removing degraded concrete layers. Different types of high-speed water jets were tested in the experimental part. The classical technology of a single continuous water jet generated with one nozzle was tested as well as the technology of revolving water jets generated by multiple nozzles (used mainly for the renovation of larger areas). A continuous flat water jet and pulsating flat water jet were tested the first time, because the connection of a water jet with the acoustic generator of a pulsating jet offers new possibilities for the use of a water jet (see [1] and [2]). A water jet with such a modification is capable of efficient action and can even be used for cutting solid concrete with a relatively low consumption of energy. A flat pulsating water jet which can be newly used for renovation seems to be a promising technology.

  7. Validating spatial structure in canopy water content using geostatistics

    Science.gov (United States)

    Sanderson, E. W.; Zhang, M. H.; Ustin, S. L.; Rejmankova, E.; Haxo, R. S.

    1995-01-01

    Heterogeneity in ecological phenomena are scale dependent and affect the hierarchical structure of image data. AVIRIS pixels average reflectance produced by complex absorption and scattering interactions between biogeochemical composition, canopy architecture, view and illumination angles, species distributions, and plant cover as well as other factors. These scales affect validation of pixel reflectance, typically performed by relating pixel spectra to ground measurements acquired at scales of 1m(exp 2) or less (e.g., field spectra, foilage and soil samples, etc.). As image analysis becomes more sophisticated, such as those for detection of canopy chemistry, better validation becomes a critical problem. This paper presents a methodology for bridging between point measurements and pixels using geostatistics. Geostatistics have been extensively used in geological or hydrogeolocial studies but have received little application in ecological studies. The key criteria for kriging estimation is that the phenomena varies in space and that an underlying controlling process produces spatial correlation between the measured data points. Ecological variation meets this requirement because communities vary along environmental gradients like soil moisture, nutrient availability, or topography.

  8. A case of thyroid storm with cardiac arrest

    Directory of Open Access Journals (Sweden)

    Nakashima Y

    2014-05-01

    Full Text Available Yutaka Nakashima,1 Tsuneaki Kenzaka,2 Masanobu Okayama,3 Eiji Kajii31Department for Support of Rural Medicine, Yamaguchi Grand Medical Center, 2Division of General Medicine, Center for Community Medicine, Jichi Medical University School of Medicine, Shimotsuke, Japan; 3Division of Community and Family Medicine, Center for Community Medicine, Jichi Medical University School of Medicine, Shimotsuke, JapanAbstract: A 23-year-old man became unconscious while jogging. He immediately received basic life support from a bystander and was transported to our hospital. On arrival, his spontaneous circulation had returned from a state of ventricular fibrillation and pulseless electrical activity. Following admission, hyperthyroidism led to a suspicion of thyroid storm, which was then diagnosed as a possible cause of the cardiac arrest. Although hyperthyroidism-induced cardiac arrest including ventricular fibrillation is rare, it should be considered when diagnosing the cause of treatable cardiac arrest.Keywords: hyperthyroidism, ventricular fibrillation, treatable cardiac arrest, cardiac arrest, cardiopulmonary arrest

  9. Structural analysis and modeling of water reactor fuel rod behavior

    International Nuclear Information System (INIS)

    Roshan Zamir, M.

    2000-01-01

    An important aspect of the design and analysis of nuclear reactor is the ability to predict the behavior of fuel elements in the adverse environment of a reactor system under normal and emergency operating conditions. To achieve these objectives and in order to provide a suitable computer code based on fundamental material properties for design and study of the thermal-mechanical behavior of water reactor fuel rods during their irradiation life and also to demonstrate the fuel rod design and modeling for students, The KIANA-1 computer program has been developed by the writer at Amir-Kabir university of technology with support of Atomic Energy Organization of Iran. KIANA-1 is an integral one-dimensional computer program for the thermal and mechanical analysis in order to predict fuel rods performance and also parameter study of Zircaloy-clad UO 2 fuel rod during steady state conditions. The code has been designed for the following main objectives: To give a solution for the steady state heat conduction equation for fuel as a heat source and clad by using finite difference, control volume and semi-analytical methods in order to predict the temperature profile in the fuel and cladding. To predict the inner gas pressures due to the filling gases and released gaseous fission products. To predict the fission gas production and release by using a simple diffusion model based on the Booth models and an empirical model. To calculate the fuel-clad gap conductance for cracked fuel with partial contact zones to a closed gap with strong contact. To predict the distribution of stress in three principal directions in the fuel and sheet by assuming one-dimensional plane strain and asymmetric idealization. To calculate the strain distribution in three principal directions and the corresponding deformation in the fuel and cladding. For this purpose the permanent strain such as creep or plasticity as well as the thermoelastic deformation and also the swelling, densification, cracking

  10. Hydroxylated PBDEs induce developmental arrest in zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Usenko, Crystal Y., E-mail: Crystal_usenko@baylor.edu; Hopkins, David C.; Trumble, Stephen J., E-mail: Stephen_trumble@baylor.edu; Bruce, Erica D., E-mail: Erica_bruce@baylor.edu

    2012-07-01

    The ubiquitous spread of polybrominated diphenyl ethers (PBDEs) has led to concerns regarding the metabolites of these congeners, in particular hydroxylated PBDEs. There are limited studies regarding the biological interactions of these chemicals, yet there is some concern they may be more toxic than their parent compounds. In this study three hydroxylated PBDEs were assessed for toxicity in embryonic zebrafish: 3-OH-BDE 47, 5-OH-BDE 47, and 6-OH-BDE 47. All three congeners induced developmental arrest in a concentration-dependent manner; however, 6-OH-BDE 47 induced adverse effects at lower concentrations than the other congeners. Furthermore, all three induced cell death; however apoptosis was not observed. In short-term exposures (24–28 hours post fertilization), all hydroxylated PBDEs generated oxidative stress in the region corresponding to the cell death at 5 and 10 ppm. To further investigate the short-term effects that may be responsible for the developmental arrest observed in this study, gene regulation was assessed for embryos exposed to 0.625 ppm 6-OH-BDE 47 from 24 to 28 hpf. Genes involved in stress response, thyroid hormone regulation, and neurodevelopment were significantly upregulated compared to controls; however, genes related to oxidative stress were either unaffected or downregulated. This study suggests that hydroxylated PBDEs disrupt development, and may induce oxidative stress and potentially disrupt the cholinergic system and thyroid hormone homeostasis. -- Highlights: ► OH-PBDEs induce developmental arrest in a concentration-dependent manner. ► Hydroxyl group location influences biological interaction. ► OH-PBDEs induce oxidative stress. ► Thyroid hormone gene regulation was disrupted following exposure. ► To our knowledge, this is the first whole organism study of OH-PBDE toxicity.

  11. Flow and coherent structures around circular cylinders in shallow water

    Science.gov (United States)

    Zeng, Jie; Constantinescu, George

    2017-06-01

    Eddy-resolving numerical simulations are conducted to investigate the dynamics of the large-scale coherent structures around a circular cylinder in an open channel under very shallow flow conditions where the bed friction significantly affects the wake structure. Results are reported for three test cases, for which the ratio between the cylinder diameter, D, and the channel depth, H, is D/H = 10, 25, and 50, respectively. Simulation results show that a horseshoe vortex system forms in all test cases and the dynamics of the necklace vortices is similar to that during the breakaway sub-regime observed for cases when a laminar horseshoe vortex forms around the base of the cylinder. Given the shallow conditions and turbulence in the incoming channel flow, the necklace vortices occupy a large fraction of the flow depth (they penetrate until the free surface in the shallower cases with D/H = 25 and 50). The oscillations of the necklace vortices become less regular with increasing polar angle magnitude and can induce strong amplification of the bed shear stress beneath their cores. Strong interactions are observed between the legs of the necklace vortices and the eddies shed in the separated shear layers in the cases with D/H = 25 and 50. In these two cases, a vortex-street type wake is formed and strong three-dimensional effects are observed in the near-wake flow. A secondary instability in the form of arrays of co-rotating parallel horizontal vortices develops. Once the roller vortices get away from the cylinder, the horizontal vortices in the array orient themselves along the streamwise direction. This instability is not present for moderately shallow conditions (e.g., D/H ≈ 1) nor for very shallow cases when the wake changes to an unsteady bubble type (e.g., D/H = 50). For cases when this secondary instability is present, the horizontal vortices extend vertically over a large fraction of the flow depth and play an important role in the vertical mixing of fluid

  12. Crack arrest concepts for failure prevention and life extension. Proceedings

    International Nuclear Information System (INIS)

    Wiesner, C.S.

    1996-01-01

    These proceedings contain the thirteen papers presented at a seminar on crack arrest concepts for failure prevention and life extension. They provide a picture of the current position of crack arrest testing, models and applications, discussion of the relevance of recent research to industrial problems, and an assessment of whether the application of crack arrest models provides additional safety. Separate abstracts have been prepared for seven papers of relevance to the nuclear industry and, in particular, reactor pressure vessels. (UK)

  13. Spatial organization and drivers of the virtual water trade: a community-structure analysis

    International Nuclear Information System (INIS)

    D’Odorico, Paolo; Carr, Joel; Laio, Francesco; Ridolfi, Luca

    2012-01-01

    The trade of agricultural commodities can be associated with a virtual transfer of the local freshwater resources used for the production of these goods. Thus, trade of food products virtually transfers large amounts of water from areas of food production to far consumption regions, a process termed the ‘globalization of water’. We consider the (time-varying) community structure of the virtual water network for the years 1986–2008. The communities are groups of countries with dense internal connections, while the connections are sparser among different communities. Between 1986 and 2008, the ratio between virtual water flows within communities and the total global trade of virtual water has continuously increased, indicating the existence of well defined clusters of virtual water transfers. In some cases (e.g. Central and North America and Europe in recent years) the virtual water communities correspond to geographically coherent regions, suggesting the occurrence of an ongoing process of regionalization of water resources. However, most communities also include countries located on different ‘sides’ of the world. As such, geographic proximity only partly explains the community structure of virtual water trade. Similarly, the global distribution of people and wealth, whose effect on the virtual water trade is expressed through simple ‘gravity models’, is unable to explain the strength of virtual water communities observed in the past few decades. A gravity model based on the availability of and demand for virtual water in different countries has higher explanatory power, but the drivers of the virtual water fluxes are yet to be adequately identified. (letter)

  14. [Biological testing of water with different structural states in rats and frogs].

    Science.gov (United States)

    Farashchuk, N F; Mikhaylova, R I; Telenkova, O G

    2014-01-01

    The effect of water samples with different structural states on some physiological indices of white laboratory rats, 5 groups of 10 animals (5 females and 5 males) and frogs has been studied. The investigation was performed for 1 month. For the determination of the content of liquid crystal associates (LCA) in water samples there was used the dilatometric method, the performance of experimental animals was studied by the swimming test (up to total fatigue). The performed experiment on growing rats with the use of water with varying degrees of structuredness showed that according to the weight gain there were optimal water "Lekor" and tap water, treated with Bioptron (the content of the structured fraction is 5.06 +/- 0.09% and 6.9 +/- 0.23%, respectively). On physical performance the best indices were in animals consumed water treated with the Bioptron lamp. In performance of experiments on frogs it was found that cardiac function in animals under experimental conditions over time weakens spontaneously: heart rate and cardiac output decline. Therefore, the effect of different water samples on the cardiac function was assessed on the intensity of its decrease for 15 minutes. In the experimental study of the effect of water with different content of LCA on heart rate and cardiac output of the frog it was found that the optimum level of structuredness of water is within the range of 5.06 +/- 0.09% (in water "Lekor") - 6.9 +/- 0.23% (tap water treated with Bioptron). All the other water samples, the content of nanocrystals in which was below or above this range, has a pronounced inhibitory effect on the heart performance of the frog.

  15. The geomorphic legacy of water and erosion control structures in a semiarid rangeland watershed

    Science.gov (United States)

    Nichols, Mary H.; Magirl, Christopher S.; Sayre, N.F.; Shaw, Jeremy R.

    2018-01-01

    Control over water supply and distribution is critical for agriculture in drylands where manipulating surface runoff often serves the dual purpose of erosion control. However, little is known of the geomorphic impacts and legacy effects of rangeland water manipulation infrastructure, especially if not maintained. This study investigated the geomorphic impacts of structures such as earthen berms, water control gates, and stock tanks, in a semiarid rangeland in the southwestern USA that is responding to both regional channel incision that was initiated over a century ago, and a more recent land use change that involved cattle removal and abandonment of structures. The functional condition of remnant structures was inventoried, mapped, and assessed using aerial imagery and lidar data. Headcut initiation, scour, and channel incision associated with compromised lateral channel berms, concrete water control structures, floodplain water spreader berms, and stock tanks were identified as threats to floodplains and associated habitat. Almost half of 27 identified lateral channel berms (48%) have been breached and 15% have experienced lateral scour; 18% of 218 shorter water spreader berms have been breached and 17% have experienced lateral scour. A relatively small number of 117 stock tanks (6%) are identified as structurally compromised based on analysis of aerial imagery, although many currently do not provide consistent water supplies. In some cases, the onset of localized disturbance is recent enough that opportunities for mitigation can be identified to alter the potentially damaging erosion trajectories that are ultimately driven by regional geomorphic instability. Understanding the effects of prior land use and remnant structures on channel and floodplain morphologic condition is critical because both current land management and future land use options are constrained by inherited land use legacy effects.

  16. Structure and Conceptual Design of a Water-Hammering-Type Honsang for Restoration

    Directory of Open Access Journals (Sweden)

    Yong Sam Lee

    2012-06-01

    Full Text Available We analyzed the manufacturing procedure, specifications, repair history, and details of celestial movements of the water-hammering type Honsang (celestial globe. Results from our study on the remaining Honsangs in China and Japan and on the reconstruction models in Korea were applied to our conceptual design of the water-hammering type Honsang. A Honui (armillary sphere and Honsang using the water-hammering method were manufactured in Joseon in 1435 (the 17th year of King Sejong. Jang Yeong-Sil developed the Honsang system based on the water-operation method of Shui yün i hsiang t’ai in China. Water-operation means driving water wheels using a water flow. The most important factor in this type of operation is the precision of the water clock and the control of the water wheel movement. The water-hammering type Honsang in Joseon probably adopted the Cheonhyeong (天衡; oriental escapement device system of Shui yün i hsiang t’ai in China and the overflow mechanism of Jagyeongnu (striking clepsydra in Joseon, etc. In addition to the Cheonryun system, more gear instruments were needed to stage the rotation of the Honsang globe and the sun’s movement. In this study, the water-hammering mechanism is analyzed in the structure of a water clock, a water wheel, the Cheonhyeong system, and the Giryun system, as an organically working operation mechanism. We expect that this study will serve as an essential basis for studies on Heumgyeonggaknu, the water-operating astronomical clock, and other astronomical clocks in the middle and latter parts of the Joseon dynasty.

  17. Molecular Structure and Dynamics in Thin Water Films at the Silica and Graphite Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Argyris, Dr. Dimitrios [University of Oklahoma; Tummala, Dr. Naga Rajesh [University of Oklahoma; StrioloDr., A [Vanderbilt University; Cole, David R [ORNL

    2008-01-01

    The structure and dynamic properties of interfacial water at the graphite and silica solid surfaces were investigated using molecular dynamics simulations. The effect of surface properties on the characteristics of interfacial water was quantified by computing density profiles, radial distribution functions, surface density distributions, orientation order parameters, and residence and reorientation correlation functions. In brief, our results show that the surface roughness, chemical heterogeneity, and surface heterogeneous charge distribution affect the structural and dynamic properties of the interfacial water molecules, as well as their rate of exchange with bulk water. Most importantly, our results indicate the formation of two distinct water layers at the SiO2 surface covered by a large density of hydroxyl groups. Further analysis of the data suggests a highly confined first layer where the water molecules assume preferential hydrogen-down orientation and a second layer whose behavior and characteristics are highly dependent on those of the first layer through a well-organized hydrogen bond network. The results suggest that water-water interactions, in particular hydrogen bonds, may be largely responsible for macroscopic interfacial properties such as adsorption and contact angle.

  18. Pathological links between stroke and cardiac arrest

    Institute of Scientific and Technical Information of China (English)

    Shaila Ghanekar; Sydney Corey; Trenton Lippert; Cesar V.Borlongan

    2017-01-01

    There may be a pathological connection between cardiac failure and ischemic stroke.In this article we describe pertinent research that demonstrates subsequent death of cardiac and neural myocytes in the post ischemic stroke brain.Current stroke therapy overlooks the connection between cardiac and cerebrovascular events and fails to address the shared risk factors.Current pre-clinical stroke investigations have provided evidence that suggests the presence of an indirect cell death pathway in which toxic molecules emanate from the stroke brain and trigger cardiac cell death.On the other hand,other studies highlight the presence of a reverse cell death cascade in which toxic molecules from the heart,following cardiac arrest,travel to the brain and induce ischemic cell death.Further examination of these putative cell death pathways between ischemic stroke and cardiac arrest will prompt the advancement of innovative treatments specifically targeting both diseases,leading to ameliorated clinical results of patients diagnosed with heart failure and ischemic stroke.

  19. Cerebral intolerance during flow arrested carotid angioplasty.

    Science.gov (United States)

    St Louis, Myron; Park, Brian D; Dahn, Michael; Bozeman, Patricia

    2012-01-01

    The use of flow arrest as a means of providing cerebral protection during carotid angioplasty offers the advantages of improved efficiency of debris removal and the ability to provide protection under unfavorable (tortuous) anatomic circumstances. However, in contrast to the filtration methods of cerebral protection, this modality requires complete interruption of antegrade carotid artery flow during balloon angioplasty and stent deployment. We report our experience with 9 patients undergoing carotid angioplasty with the Mo.Ma device, which utilizes common and external carotid artery balloon occlusion during the angioplasty procedure. We assessed the clinical outcomes and intraprocedural hemodynamic data. The average duration of carotid occlusion was 8.3 minutes. Of the 9 patients, 2 patients (22%) experienced cerebral intolerance. No stroke occurred in this patient cohort. There appeared to be a poor relationship between procedure intolerance and the presence of significant contralateral stenosis or low carotid back pressure. Furthermore, the incidence of postangioplasty hypotension was not clearly related to cerebral intolerance. Carotid angioplasty with stenting can be safely conducted with flow arrest as an alternative to filter-type cerebral protection devices. However, because cerebral intolerance is not an infrequent occurrence with this approach, clinicians must be cognizant of management strategies for transient cerebral intolerance.

  20. Hydroxide diffuses slower than hydronium in water because its solvated structure inhibits correlated proton transfer

    Science.gov (United States)

    Chen, Mohan; Zheng, Lixin; Santra, Biswajit; Ko, Hsin-Yu; DiStasio, Robert A., Jr.; Klein, Michael L.; Car, Roberto; Wu, Xifan

    2018-03-01

    Proton transfer via hydronium and hydroxide ions in water is ubiquitous. It underlies acid-base chemistry, certain enzyme reactions, and even infection by the flu. Despite two centuries of investigation, the mechanism underlying why hydroxide diffuses slower than hydronium in water is still not well understood. Herein, we employ state-of-the-art density-functional-theory-based molecular dynamics—with corrections for non-local van der Waals interactions, and self-interaction in the electronic ground state—to model water and hydrated water ions. At this level of theory, we show that structural diffusion of hydronium preserves the previously recognized concerted behaviour. However, by contrast, proton transfer via hydroxide is less temporally correlated, due to a stabilized hypercoordination solvation structure that discourages proton transfer. Specifically, the latter exhibits non-planar geometry, which agrees with neutron-scattering results. Asymmetry in the temporal correlation of proton transfer leads to hydroxide diffusing slower than hydronium.

  1. Irreversible Change of the Pore Structure of ZIF-8 in Carbon Dioxide Capture with Water Coexistence

    DEFF Research Database (Denmark)

    Liu, Huang; Guo, Ping; Regueira Muñiz, Teresa

    2016-01-01

    The performance of zeolitic imidazolate framework 8 (ZIF-8) for CO2 capture under three different conditions (wetted ZIF-8, ZIF-8/water slurry, and ZIF-8/water-glycol slurry) was systemically investigated. This investigation included the study of the pore structure stability of ZIF-8 by using X......-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and Raman detection technologies. Our results show that the CO2 adsorption ability of ZIF-8 could be substantially increased under the existence of liquid water. However, the structure characterization of the recovered ZIF-8...... showed an irreversible change of its framework, which occurs during the CO2 capture process. It was found that there is an irreversible chemical reaction among ZIF-8, water, and CO2, which creates both zinc carbonate (or zinc carbonate hydroxides) and single 2-methylimidazole crystals, and therefore...

  2. Structure and Dynamics of Water on Aqueous Barium Ion and the {001} Barite Surface

    International Nuclear Information System (INIS)

    Stack, Andrew G.; Rustad, James R.

    2007-01-01

    The structure of water and its dynamics affect a number of fundamental properties of an interface. Yet, these properties are often inaccessible experimentally and computational studies including solvent are comparatively few. Here, we estimate the structure and kinetics of water exchange of aqueous barium ions and barium ions within the {001} barite surface using molecular dynamics and the reactive flux method. For the aqueous ion, the Ba-O distance to water in the first hydration shell was found to be 280 pm with a coordination number of 8.3, and the best estimate of the exchange rate constant is 4.8 x 10 9 s -1 , closely matching experimental estimates. For the barite surface, the first shell water distance was 282 pm, with a coordination number of 0.9 and the best estimate of the rate constant for exchange is 1.7 x 10 10 s -1 , 3.5 times faster than that of the aqueous ion.

  3. Experimental Observation of Bulk Liquid Water Structure in ``No Man's Land''

    Science.gov (United States)

    Sellberg, Jonas; McQueen, Trevor; Huang, Congcong; Loh, Duane; Laksmono, Hartawan; Sierra, Raymond; Hampton, Christina; Starodub, Dmitri; Deponte, Daniel; Martin, Andrew; Barty, Anton; Wikfeldt, Thor; Schlesinger, Daniel; Pettersson, Lars; Beye, Martin; Nordlund, Dennis; Weiss, Thomas; Feldkamp, Jan; Caronna, Chiara; Seibert, Marvin; Messerschmidt, Marc; Williams, Garth; Boutet, Sebastien; Bogan, Michael; Nilsson, Anders

    2013-03-01

    Experiments on pure bulk water below about 235 K have so far been difficult: water crystallization occurs very rapidly below the homogeneous nucleation temperature of 232 K and above 160 K, leading to a ``no man's land'' devoid of experimental results regarding the structure. Here, we demonstrate a new, general experimental approach to study the structure of liquid states at supercooled conditions below their limit of homogeneous nucleation. We use femtosecond x-ray pulses generated by the LCLS x-ray laser to probe evaporatively cooled droplets of supercooled bulk water and find experimental evidence for the existence of metastable bulk liquid water down to temperatures of 223 K in the previously largely unexplored ``no man's land''. We acknoweledge NSF (CHE-0809324), Office of Basic Energy Sciences, and the Swedish Research Council for financial support.

  4. Structure/property relationships in polymer membranes for water purification and energy applications

    Science.gov (United States)

    Geise, Geoffrey

    Providing sustainable supplies of purified water and energy is a critical global challenge for the future, and polymer membranes will play a key role in addressing these clear and pressing global needs for water and energy. Polymer membrane-based processes dominate the desalination market, and polymer membranes are crucial components in several rapidly developing power generation and storage applications that rely on membranes to control rates of water and/or ion transport. Much remains unknown about the influence of polymer structure on intrinsic water and ion transport properties, and these relationships must be developed to design next generation polymer membrane materials. For desalination applications, polymers with simultaneously high water permeability and low salt permeability are desirable in order to prepare selective membranes that can efficiently desalinate water, and a tradeoff relationship between water/salt selectivity and water permeability suggests that attempts to prepare such materials should rely on approaches that do more than simply vary polymer free volume. One strategy is to functionalize hydrocarbon polymers with fixed charge groups that can ionize upon exposure to water, and the presence of charged groups in the polymer influences transport properties. Additionally, in many emerging energy applications, charged polymers are exposed to ions that are very different from sodium and chloride. Specific ion effects have been observed in charged polymers, and these effects must be understood to prepare charged polymers that will enable emerging energy technologies. This presentation discusses research aimed at further understanding fundamental structure/property relationships that govern water and ion transport in charged polymer films considered for desalination and electric potential field-driven applications that can help address global needs for clean water and energy.

  5. Molecular Descriptors Family on Structure Activity Relationships 6. Octanol-Water Partition Coefficient of Polychlorinated Biphenyls

    Directory of Open Access Journals (Sweden)

    Lorentz JÄNTSCHI

    2006-01-01

    Full Text Available Octanol-water partition coefficient of two hundred and six polychlorinated biphenyls was model by the use of an original method based on complex information obtained from compounds structure. The regression analysis shows that best results are obtained in four-varied model (r2 = 0.9168. The prediction ability of the model was studied through leave-one-out analysis (r2cv(loo = 0.9093 and in training and test sets analysis. Modeling the octanol-water partition coefficient of polychlorinated biphenyls by integration of complex structural information provide a stable and performing four-varied model, allowing us to make remarks about relationship between structure of polychlorinated biphenyls and associated octanol-water partition coefficients.

  6. Diffusion under water-saturated conditions in PFA/OPC-based structural concrete

    International Nuclear Information System (INIS)

    Harris, A.W.; Nickerson, A.K.

    1990-05-01

    A substantial proportion of the volume of the UK radioactive waste repository is likely to be composed of materials based on hydraulic cements. This includes the structural components, which are likely to be manufactured from concrete. The mass transport characteristics of dissolved species for a typical structural concrete, based on a mixture of pulverised fuel ash and ordinary Portland cement, have been measured in a water-saturated condition. Both the water permeability and the diffusion parameters (for caesium, strontium and iodide ion and tritiated water diffusion) are low compared to values obtained for other structural concretes. The intrinsic diffusion coefficients for iodide and caesium ions are in the range 2-5x10 -14 m 2 s -1 . There is no evidence of significant sorption of any of the diffusants studied. (author)

  7. Model-based leakage localization in drinking water distribution networks using structured residuals

    OpenAIRE

    Puig Cayuela, Vicenç; Rosich, Albert

    2013-01-01

    In this paper, a new model based approach to leakage localization in drinking water networks is proposed based on generating a set of structured residuals. The residual evaluation is based on a numerical method based on an enhanced Newton-Raphson algorithm. The proposed method is suitable for water network systems because the non-linearities of the model make impossible to derive analytical residuals. Furthermore, the computed residuals are designed so that leaks are decoupled, which impro...

  8. Branched ZnO wire structures for water collection inspired by cacti.

    Science.gov (United States)

    Heng, Xin; Xiang, Mingming; Lu, Zhihui; Luo, Cheng

    2014-06-11

    In this work, motivated by an approach used in a cactus to collect fog, we have developed an artificial water-collection structure. This structure includes a large ZnO wire and an array of small ZnO wires that are branched on the large wire. All these wires have conical shapes, whose diameters gradually increase from the tip to the root of a wire. Accordingly, a water drop that is condensed on the tip of each wire is driven to the root by a capillary force induced by this diameter gradient. The lengths of stem and branched wires in the synthesized structures are in the orders of 1 mm and 100 μm, respectively. These dimensions are, respectively, comparable to and larger than their counterparts in the case of a cactus. Two groups of tests were conducted at relative humidity of 100% to compare the amounts of water collected by artificial and cactus structures within specific time durations of 2 and 35 s, respectively. The amount of water collected by either type of structures was in the order of 0.01 μL. However, on average, what has been collected by the artificial structures was 1.4-5.0 times more than that harvested by the cactus ones. We further examined the mechanism that a cactus used to absorb a collected water drop into its stem. On the basis of the gained understanding, we developed a setup to successfully collect about 6 μL of water within 30 min.

  9. Structure and Dynamics in Formamide-(H2O)3: A Water Pentamer Analogue.

    Science.gov (United States)

    Blanco, Susana; Pinacho, Pablo; López, Juan Carlos

    2017-12-21

    Water self-association dominates the formation of microsolvated molecular clusters which may give rise to complex structures resembling those of pure water clusters. We present a rotational study of the complex formamide-(H 2 O) 3 formed in a supersonic jet and several monosubstituted isotopologues. Formamide and water molecules form a four-body sequential cycle through N-H···O, O-H···O, and O-H···O═C hydrogen bonds, resulting in a chiral structure with a nonplanar skeleton that can be overlapped to that of water pentamer. The analysis of the 14 N-nucleus quadrupole coupling effects shows the depletion of the electron density of the N atom lone pair with respect to the bare formamide that affects the amide group C-N and C═O distances. The study of the observed tunneling doublets shows that formamide-(H 2 O) 3 follows a path to invert its structure driven by the flipping of water subunits and passing through successive nonplanar configurations, a motion reminiscent of the pseudorotation of water pentamer.

  10. Polymer Structure and Water States in Salt-Containing Polyampholyte Hydrogels

    Science.gov (United States)

    Li, Xinda; Elliott, Janet A. W.; Lee, Byeongdu; Chung, Hyun-Joong

    The phase behavior of water in hydrogels has broad impact on various applications, such as lubrication, adhesion, and electrical conductivity, as well as the hydrogel's low temperature properties. The status of the water molecules is correlated to the structure of the polymer chains in the hydrogel. In this study, the structure and water status of a model charge-balanced polyampholyte poly(4-vinylbenzenesulfonate-co-[3-(methacryloylamino) propyl] trimethylammonium chloride), were investigated by using differential scanning calorimetry (DSC) and small-angle x-ray scattering (SAXS). A globular network structure suggested by SAXS results dictated the depression of the freezing point of water in the hydrogel, as supported by the DSC results. The polyampholyte chains undergo an irreversible collapse during dialysis in deionized water. Such collapsed hydrogels are not able to prevent freezing of water molecules. The results of both synthesis condition and post-synthesis treatments for polyampholyte hydrogels provide us insights to design optimal polyampholyte hydrogels for low temperature applications.

  11. Numerical simulation and structural optimization of the inclined oil/water separator.

    Directory of Open Access Journals (Sweden)

    Liqiong Chen

    Full Text Available Improving the separation efficiency of the inclined oil/water separator, a new type of gravity separation equipment, is of great importance. In order to obtain a comprehensive understanding of the internal flow field of the separation process of oil and water within this separator, a numerical simulation based on Euler multiphase flow analysis and the realizable k-ε two equation turbulence model was executed using Fluent software. The optimal value ranges of the separator's various structural parameters used in the numerical simulation were selected through orthogonal array experiments. A field experiment on the separator was conducted with optimized structural parameters in order to validate the reliability of the numerical simulation results. The research results indicated that the horizontal position of the dispenser, the hole number, and the diameter had significant effects on the oil/water separation efficiency, and that the longitudinal position of the dispenser and the position of the weir plate had insignificant effects on the oil/water separation efficiency. The optimal structural parameters obtained through the orthogonal array experiments resulted in an oil/water separation efficiency of up to 95%, which was 4.996% greater than that realized by the original structural parameters.

  12. The Structure and Transport of Water and Hydrated Ions Within Hydrophobic, Nanoscale Channels

    International Nuclear Information System (INIS)

    Holt, J.K.; Herberg, J.L.; Wu, Y.; Schwegler, E.; Mehta, A.

    2009-01-01

    The purpose of this project includes an experimental and modeling investigation into water and hydrated ion structure and transport at nanomaterials interfaces. This is a topic relevant to understanding the function of many biological systems such as aquaporins that efficiently shuttle water and ion channels that permit selective transport of specific ions across cell membranes. Carbon nanotubes (CNT) are model nanoscale, hydrophobic channels that can be functionalized, making them artificial analogs for these biological channels. This project investigates the microscopic properties of water such as water density distributions and dynamics within CNTs using Nuclear Magnetic Resonance (NMR) and the structure of hydrated ions at CNT interfaces via X-ray Absorption Spectroscopy (XAS). Another component of this work is molecular simulation, which can predict experimental measurables such as the proton relaxation times, chemical shifts, and can compute the electronic structure of CNTs. Some of the fundamental questions this work is addressing are: (1) what is the length scale below which nanoscale effects such as molecular ordering become important, (2) is there a relationship between molecular ordering and transport?, and (3) how do ions interact with CNT interfaces? These are questions of interest to the scientific community, but they also impact the future generation of sensors, filters, and other devices that operate on the nanometer length scale. To enable some of the proposed applications of CNTs as ion filtration media and electrolytic supercapacitors, a detailed knowledge of water and ion structure at CNT interfaces is critical.

  13. Stomatal structure and physiology do not explain differences in water use among montane eucalypts.

    Science.gov (United States)

    Gharun, Mana; Turnbull, Tarryn L; Pfautsch, Sebastian; Adams, Mark A

    2015-04-01

    Understanding the regulation of water use at the whole-tree scale is critical to advancing the utility of physiological ecology, for example in its role in predictive hydrology of forested catchments. For three eucalypt species that dominate high-elevation catchments in south-eastern Australia, we examined if whole-tree water use could be related to three widely discussed regulators of water use: stomatal anatomy, sensitivity of stomata [i.e. stomatal conductance (g(s))] to environmental influences, and sapwood area. While daily tree water use varied sixfold among species, sap velocity and sapwood area varied in parallel. Combined, stomatal structure and physiology could not explain differences in species-specific water use. Species which exhibited the fastest (Eucalyptus delegatensis) and slowest (Eucalyptus pauciflora) rates of water use both exhibited greater capacity for physiological control of g(s) [indicated by sensitivity to vapour pressure deficit (VPD)] and a reduced capacity to limit g(s) anatomically [indicated by greater potential g(s) (g(max))]. Conversely, g(s) was insensitive to VPD and g(max) was lowest for Eucalyptus radiata, the species showing intermediate rates of water use. Improved knowledge of stomatal anatomy will help us to understand the capacity of species to regulate leaf-level water loss, but seems likely to remain of limited use for explaining rates of whole-tree water use in montane eucalypts at the catchment scale.

  14. Structural Models of Water and Ice Regarding the Energy of Hydrogen Bonding

    OpenAIRE

    Ignat Ignatov; Oleg Mosin

    2015-01-01

    In this review it is reported about the research on the structure of water and ice and intermolecular water cyclic associates (clusters) with general formula (Н2О)n and their charged ionic clusters [(Н2О)n]+ and [(Н2О)n]- by means of computer modelling and spectroscopy methods as 1Н-NMR, IR-spectroscopy, DNES, EXAFS-spectroscopy, X-Ray and neurons diffraction. The computer calculation of polyhedral nanoclusters (Н2О)n, where n = 3–20 are carried out. Based on this data the main structural mat...

  15. Method to study water hammer with fluid-structure interaction in spatial pipe

    International Nuclear Information System (INIS)

    Xi Zhide; Ma Jianzhong; Sun Lei

    2013-01-01

    The theory of coupling 4-function models and its solution approach are first introduced in this paper, and the method of CFD to calculate fluid-structure interaction is also introduced. Finally, the model in related reference is applied with this method to simulate the process of water hammer. By CFD calculation for the classical water hammer, the numerical scheme and grid are selected, and the results of CFD are compared with reference. The results show that the method in this paper can be used in more complex pipe system to simulate the water hammer effect. (authors)

  16. Water-mediated variability in the structure of relaxed-state haemoglobin

    International Nuclear Information System (INIS)

    Kaushal, Prem Singh; Sankaranarayanan, R.; Vijayan, M.

    2008-01-01

    Partial dehydration of high-salt horse methaemoglobin crystals tends to shift the structure from the R state to the R2 state, in agreement with previous observations that movements in the molecule resulting from changes in water content mimic those involved in protein action. The crystal structure of high-salt horse methaemoglobin has been determined at environmental relative humidities (r.h.) of 88, 79, 75 and 66%. The molecule is in the R state in the native and the r.h. 88% crystals. At r.h. 79%, the water content of the crystal is reduced and the molecule appears to move towards the R2 state. The crystals undergo a water-mediated transformation involving a doubling of one of the unit-cell parameters and an increase in water content when the environmental humidity is further reduced to r.h. 75%. The water content is now similar to that in the native crystals and the molecules are in the R state. The crystal structure at r.h. 66% is similar, but not identical, to that at r.h. 75%, but the solvent content is substantially reduced and the molecules have a quaternary structure that is in between those corresponding to the R and R2 states. Thus, variation in hydration leads to variation in the quaternary structure. Furthermore, partial dehydration appears to shift the structure from the R state to the R2 state. This observation is in agreement with the earlier conclusion that the changes in protein structure that accompany partial dehydration are similar to those that occur during protein action

  17. The changes of macroscopic features and microscopic structures of water under influence of magnetic field

    International Nuclear Information System (INIS)

    Pang Xiaofeng; Deng Bo

    2008-01-01

    Influences of magnetic field on microscopic structures and macroscopic properties of water are studied by the spectrum techniques of infrared, Raman, visible, ultraviolet lights and X-ray. From these investigations, we know that the magnetic fields change the distribution of molecules and electrons, cause displacements and polarization of molecules and atoms, result in changes of dipole-moment transition and vibrational states of molecules and variation of transition probability of electrons, but does not alter the constitution of molecules and atoms. These are helpful in seeking the mechanism of magnetization of water. Meanwhile, we also measure the changed rules of the surface tension force, soaking effect or angle of contact, viscosity, rheology features, refraction index, dielectric constant and electric conductivity of magnetized water relative to that of pure water. The results show that the magnetic fields increase the soaking degree and hydrophobicity of water to materials, depress its surface-tension force, diminish the viscosity of war, enhance the feature of plastic flowing of water, and increase the refraction index, dielectric constant and electric conductivity of water after magnetization. These changes are caused by the above changes of microscopic structures under the action of magnetic field. Therefore, our studies are significant in science and has practical value of applications

  18. Prediction of the effects of size and morphology on the structure of water around hematite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Spagnoli, D.; Gilbert, B.; Waychunas, G.A.; Banfield, J. F.

    2009-05-15

    Compared with macroscopic surfaces, the structure of water around nanoparticles is difficult to probe directly. We used molecular dynamics simulations to investigate the effects of particle size and morphology on the time-averaged structure and the dynamics of water molecules around two sizes of hematite ({alpha}-Fe{sub 2}O{sub 3}) nanoparticles. Interrogation of the simulations via atomic density maps, radial distribution functions and bound water residence times provide insight into the relationships between particle size and morphology and the behavior of interfacial water. Both 1.6 and 2.7 nm particles are predicted to cause the formation of ordered water regions close to the nanoparticle surface, but the extent of localization and ordering, the connectivity between regions of bound water, and the rates of molecular exchange between inner and outer regions are all affected by particle size and morphology. These findings are anticipated to be relevant to understanding the rates of interfacial processes involving water exchange and the transport of aqueous ions to surface sites.

  19. Structure of ionic liquid-water mixtures at interfaces: x-ray and neutron reflectometry studies

    International Nuclear Information System (INIS)

    Lauw, Yansen; Rodopoulos, Theo; Horne, Mike; Follink, Bart; Hamilton, Bill; Knott, Robert; Nelson, Andy

    2009-01-01

    Full text: Fundamental studies on the effect of water in ionic liquids are necessary since the overall performance of ionic liquids in many industrial applications is often hampered by the presence of water.[1] Based on this understanding, the surface and interfacial structures of 1-butyl-1methylpyrrolidinium trifluoromethylsulfonylimide [C4mpyr][NTf2] ionic liquid-water mixtures were probed using x-ray and neutron reflectometry techniques. At the gas-liquid surface, a thick cation+water layer was detected next to the phase boundary, followed by an increasing presence of anion towards the bulk. The overall thickness of the surface exhibits non-monotonic trends with an increasing water content, which explains similar phenomenological trends in surface tension reported in the literature.[2] At an electrified interface, the interfacial structure of pure ionic liquids probed by neutron reflectometry shows similar trends to those predicted by a mean-field model.[3] However, the presence of water within the electrical double-layer is less obvious, although it is widely known that water reduces electrochemical window of ionic liquids. To shed light on this issue, further studies are currently in progress.

  20. Molecular Structure and Dynamics of Water on Pristine and Strained Phosphorene: Wetting and Diffusion at Nanoscale.

    Science.gov (United States)

    Zhang, Wei; Ye, Chao; Hong, Linbi; Yang, Zaixing; Zhou, Ruhong

    2016-12-06

    Phosphorene, a newly fabricated two-dimensional (2D) nanomaterial, has emerged as a promising material for biomedical applications with great potential. Nonetheless, understanding the wetting and diffusive properties of bio-fluids on phosphorene which are of fundamental importance to these applications remains elusive. In this work, using molecular dynamics (MD) simulations, we investigated the structural and dynamic properties of water on both pristine and strained phosphorene. Our simulations indicate that the diffusion of water molecules on the phosphorene surface is anisotropic, with strain-enhanced diffusion clearly present, which arises from strain-induced smoothing of the energy landscape. The contact angle of water droplet on phosphorene exhibits a non-monotonic variation with the transverse strain. The structure of water on transverse stretched phosphorene is demonstrated to be different from that on longitudinal stretched phosphorene. Moreover, the contact angle of water on strained phosphorene is proportional to the quotient of the longitudinal and transverse diffusion coefficients of the interfacial water. These findings thereby offer helpful insights into the mechanism of the wetting and transport of water at nanoscale, and provide a better foundation for future biomedical applications of phosphorene.

  1. Hydrate phase equilibrium and structure for (methane + ethane + tetrahydrofuran + water) system

    International Nuclear Information System (INIS)

    Sun Changyu; Chen Guangjin; Zhang Lingwei

    2010-01-01

    The separation of methane and ethane through forming hydrate is a possible choice in natural gas, oil processing, or ethylene producing. The hydrate formation conditions of five groups of (methane + ethane) binary gas mixtures in the presence of 0.06 mole fraction tetrahydrofuran (THF) in water were obtained at temperatures ranging from (277.7 to 288.2) K. In most cases, the presence of THF in water can lower the hydrate formation pressure of (methane + ethane) remarkably. However, when the composition of ethane is as high as 0.832, it is more difficult to form hydrate than without THF system. Phase equilibrium model for hydrates containing THF was developed based on a two-step hydrate formation mechanism. The structure of hydrates formed from (methane + ethane + THF + water) system was also determined by Raman spectroscopy. When THF concentration in initial aqueous solution was only 0.06 mole fraction, the coexistence of structure I hydrate dominated by ethane and structure II hydrate dominated by THF in the hydrate sample was clearly demonstrated by Raman spectroscopic data. On the contrary, only structure II hydrate existed in the hydrate sample formed from (methane + ethane + THF + water) system when THF concentration in initial aqueous solution was increased to 0.10 mole fraction. It indicated that higher THF concentration inhibited the formation of structure I hydrate dominated by ethane and therefore lowered the trapping of ethane in hydrate. It implies a very promising method to increase the separation efficiency of methane and ethane.

  2. Distribution and arrest of vertical through-going joints in a seismic-scale carbonate platform exposure (Sorrento peninsula, Italy): insights from integrating field survey and digital outcrop model

    Science.gov (United States)

    Corradetti, A.; Tavani, S.; Parente, M.; Iannace, A.; Vinci, F.; Pirmez, C.; Torrieri, S.; Giorgioni, M.; Pignalosa, A.; Mazzoli, S.

    2018-03-01

    Through-going joints cutting across beds are often invoked to match large-scale permeability patterns in tight carbonate reservoirs. However, despite the importance of these structures for fluid flow, only few field studies focused on the understanding and estimation of through-going joint dimensional parameters, including spacing and vertical extent in relation to stratigraphy. Recent improvements in the construction of digital models of outcrops can greatly help to overcome many logistic issues, favouring the evaluation of relationships between jointing and stratigraphy at the reservoir scale. In this study, we present the results obtained from integrating field measurements with a digital outcrop model of a carbonate platform reservoir analogue in the Sorrento peninsula (Italy). The outcrop consists of a nearly vertical cliff exposing a monocline of alternating gently-dipping shallow-water limestones and dolostones, crossed by several vertical joints of different size. This study allowed us to define how major through-going joints pass across thick beds (bed thickness > 30 cm), while they arrest against packages made of thinly stratified layers. In essence, through-going joints arrest on "weak" levels, consisting of thinly bedded layers interposed between packages made of thick beds, in the same manner as bed-confined joints arrest on less competent interlayers.

  3. Structural analysis on mutation residues and interfacial water molecules for human TIM disease understanding

    Science.gov (United States)

    2013-01-01

    Background Human triosephosphate isomerase (HsTIM) deficiency is a genetic disease caused often by the pathogenic mutation E104D. This mutation, located at the side of an abnormally large cluster of water in the inter-subunit interface, reduces the thermostability of the enzyme. Why and how these water molecules are directly related to the excessive thermolability of the mutant have not been investigated in structural biology. Results This work compares the structure of the E104D mutant with its wild type counterparts. It is found that the water topology in the dimer interface of HsTIM is atypical, having a "wet-core-dry-rim" distribution with 16 water molecules tightly packed in a small deep region surrounded by 22 residues including GLU104. These water molecules are co-conserved with their surrounding residues in non-archaeal TIMs (dimers) but not conserved across archaeal TIMs (tetramers), indicating their importance in preserving the overall quaternary structure. As the structural permutation induced by the mutation is not significant, we hypothesize that the excessive thermolability of the E104D mutant is attributed to the easy propagation of atoms' flexibility from the surface into the core via the large cluster of water. It is indeed found that the B factor increment in the wet region is higher than other regions, and, more importantly, the B factor increment in the wet region is maintained in the deeply buried core. Molecular dynamics simulations revealed that for the mutant structure at normal temperature, a clear increase of the root-mean-square deviation is observed for the wet region contacting with the large cluster of interfacial water. Such increase is not observed for other interfacial regions or the whole protein. This clearly suggests that, in the E104D mutant, the large water cluster is responsible for the subunit interface flexibility and overall thermolability, and it ultimately leads to the deficiency of this enzyme. Conclusions Our study

  4. Association of National Initiatives to Improve Cardiac Arrest Management With Rates of Bystander Intervention and Patient Survival After Out-of-Hospital Cardiac Arrest

    DEFF Research Database (Denmark)

    Wissenberg, Mads; Lippert, Freddy K; Folke, Fredrik

    2013-01-01

    resuscitation was attempted were identified between 2001 and 2010 in the nationwide Danish Cardiac Arrest Registry. Of 29 111 patients with cardiac arrest, we excluded those with presumed noncardiac cause of arrest (n = 7390) and those with cardiac arrests witnessed by emergency medical services personnel (n...

  5. Shock modon: a new type of coherent structure in rotating shallow water.

    Science.gov (United States)

    Lahaye, Noé; Zeitlin, Vladimir

    2012-01-27

    We show that a new type of coherent structure, a shock modon, exists in a rotating shallow water model at large Rossby numbers. It is a combination of an asymmetric vortex dipole with a stationary hydraulic jump. The structure is long living, despite the energy dissipation by the hydraulic jump, and moving along a circular path. Collisions of shock modons can be elastic, or lead to formation of shock tripoles.

  6. Performance of Surge Arrester Installation to Enhance Protection

    Directory of Open Access Journals (Sweden)

    Mbunwe Muncho Josephine

    2017-01-01

    Full Text Available The effects of abnormal voltages on power system equipment and appliances in the home have raise concern as most of the equipments are very expensive. Each piece of electrical equipment in an electrical system needs to be protected from surges. To prevent damage to electrical equipment, surge protection considerations are paramount to a well designed electrical system. Lightning discharges are able to damage electric and electronic devices that usually have a low protection level and these are influenced by current or voltage pulses with a relatively low energy, which are induced by lightning currents. This calls for proper designed and configuration of surge arresters for protection on the particular appliances. A more efficient non-linear surge arrester, metal oxide varistor (MOV, should be introduced to handle these surges. This paper shows the selection of arresters laying more emphasis on the arresters for residential areas. In addition, application and installation of the arrester will be determined by the selected arrester. This paper selects the lowest rated surge arrester as it provides insulation when the system is under stress. It also selected station class and distribution class of arresters as they act as an open circuit under normal system operation and to bring the system back to its normal operation mode as the transient voltage is suppressed. Thus, reduces the risk of damage, which the protection measures can be characterized, by the reduction value of the economic loss to an acceptable level.

  7. Cardiac arrest during anesthesia at a University Hospital in Nigeria ...

    African Journals Online (AJOL)

    Background: We assessed the incidence and outcomes of cardiac arrest during anesthesia in the operating room at our university hospital. A previous study on intraoperative cardiac arrests covered a period from 1994-1998 and since then; anesthetic personnel, equipment, and workload have increased remarkably.

  8. Efficacy of silver diamine fluoride for Arresting Caries Treatment.

    NARCIS (Netherlands)

    Yee, R.T.F.; Holmgren, C.J.; Mulder, J.; Lama, D.; Walker, D.; Palenstein Helderman, W.H. van

    2009-01-01

    Arresting Caries Treatment (ACT) has been proposed to manage untreated dental caries in children. This prospective randomized clinical trial investigated the caries-arresting effectiveness of a single spot application of: (1) 38% silver diamine fluoride (SDF) with tannic acid as a reducing agent;

  9. Cooling the crisis: Therapeutic hypothermia after sickle cardiac arrest

    NARCIS (Netherlands)

    Metske, Hennie A.; Postema, Pieter G.; Biemond, Bart J.; Bouman, Catherine S. C.

    2012-01-01

    Objective: The management of patients with sickle-cell disease and cardiac arrest presents special challenges. Mild therapeutic hypothermia may improve survival and neurologic outcome after cardiac arrest, however, it may also precipitate sickling in patients with sickle-cell disease. Rigorous

  10. 29 CFR 1915.159 - Personal fall arrest systems (PFAS).

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Personal fall arrest systems (PFAS). 1915.159 Section 1915... Protective Equipment (PPE) § 1915.159 Personal fall arrest systems (PFAS). The criteria of this section apply to PFAS and their use. Effective January 1, 1998, body belts and non-locking snaphooks are not...

  11. Impact of curved shaped energy dissipaters downstream of head structures on both water energy dissipation and irrigation water quality

    Directory of Open Access Journals (Sweden)

    Ashour Mohamed A.

    2015-03-01

    Full Text Available Using energy dissipaters on the soled aprons downstream of head structures is the main technique for accelerating hydraulic jump formation and dissipating a great amount of the residual harmful kinetic energy occurring downstream of head structures. In this paper, an experimental study was conducted to investigate some untested shapes of curved dissipaters with different angles of curvature and arrangements from two points of view. The first is to examine its efficiency in dissipating the kinetic water energy. The second is to examine the most effective shape and arrangement obtained from the aforementioned step in enriching the flow with dissolved oxygen for enhancement of the irrigation water quality. The study was held in the irrigation and hydraulic laboratory of the Civil Department, Faculty of Engineering, Assiut University, using a movable bed tilting channel 20 m long, 30 cm wide, and 50 cm high, using 21 types of curved dissipaters with different arrangements. A total of 660 runs were carried out. Results were analysed, tabulated and graphically presented, and new formulas were introduced to estimate the energy dissipation ratio, as well as the DO concentrations. Results in general showed that the dissipater performance is more tangible in dissipating the residual energy when the curvature is in the opposite direction to that of the flow. Also, the energy loss ratio increases with an increase in curvature angle (θ, until it reaches (θ = 120°, then it decreases again. The study also showed that using three rows of dissipaters give nearly the same effect as using four rows, concerning both the relative energy dissipation and dissolved oxygen content. So, it is recommended to use three rows of the curved dissipater with the angle of curvature (θ = 120° in the opposite direction to that of the flow to obtain the maximum percentage of water energy dissipation downstream of head structures, and maximum dissolved oxygen content too

  12. Maturation arrest of human oocytes at germinal vesicle stage

    Directory of Open Access Journals (Sweden)

    Zhi Qin Chen

    2010-01-01

    Full Text Available Maturation arrest of human oocytes may occur at various stages of the cell cycle. A total failure of human oocytes to complete meiosis is rarely observed during assisted conception cycles. We describe here a case of infertile couples for whom all oocytes repeatedly failed to mature at germinal vesicle (GV stage during in vitro fertilization/Intra cytoplasmic sperm injection (IVF/ICSI. The patient underwent controlled ovarian stimulation followed by oocyte retrieval and IVF/ICSI. The oocytes were stripped off cumulus cells prior to the ICSI procedure and their maturity status was defined. The oocyte maturation was repeatedly arrested at the GV. Oocyte maturation arrest may be the cause of infertility in this couple. The recognition of oocyte maturation arrest as a specific medical condition may contribute to the characterization of the currently known as "oocyte factor." The cellular and genetic mechanisms causing oocyte maturation arrest should be the subject for further investigation.

  13. Water

    Science.gov (United States)

    ... www.girlshealth.gov/ Home Nutrition Nutrition basics Water Water Did you know that water makes up more ... to drink more water Other drinks How much water do you need? top Water is very important, ...

  14. Social and Structural Patterns of Drought-Related Water Conservation and Rebound

    Science.gov (United States)

    Gonzales, Patricia; Ajami, Newsha

    2017-12-01

    Water use practices and conservation are the result of complex sociotechnical interactions of political, economic, hydroclimatic, and social factors. While the drivers of water demand have been extensively studied, they have traditionally been applied to models that assume stationary relationships between these various factors, and usually do not account for potential societal changes in response to increased scarcity awareness. For example, following a period of sustained low demand such as during a drought, communities often increase water use during a hydrologically wet period, a phenomenon known as "rebounding" water use. Previous experiences show the extent of this rebound is not a straightforward function of policy and efficiency improvements, but may also reflect short-term or long-lasting change in community behavior, which are not easily captured by models that assume stationarity. In this work, we develop a system dynamics model to represent water demand as a function of both structural and social factors. We apply this model to the analysis of three diverse water utilities in the San Francisco Bay Area between 1980 and 2017, identifying drought response trends and drivers over time. Our model is consistent with empirical patterns and historical context of water use in California, and provides important insights on the rebound phenomenon that can be extended to other locations. This comparative assessment indicates that policies, public outreach, and better data availability have played a key role in raising public awareness of water scarcity, especially with the raise of the internet era in recent years.

  15. Growth arrest specific protein (GAS) 6

    DEFF Research Database (Denmark)

    Haase, T N; Rasmussen, Morten; Jaksch, C A M

    2013-01-01

    using RNA microarray and quantitative PCR. The role of a differentially expressed gene, growth arrest specific protein 6 (GAS6), was evaluated in vitro using neonatal rat islets. Results The mRNA level of Gas6, known to be mitogenic in other tissues, was reduced in LP offspring. The mRNA content of Mafa...... was increased in LP offspring suggesting an early maturation of beta cells. When applied in vitro, GAS6 increased proliferation of neonatal pancreatic beta cells, while reducing glucose-stimulated insulin secretion without changing the total insulin content of the islets. In addition, GAS6 decreased the m......RNA content of Mafa. Conclusions/interpretation We propose a role for GAS6 in the regulation of pancreatic beta cells in the critical period around the time of birth. Our results support the hypothesis that the reduced beta cell mass seen in LP offspring is caused by a change in the intra-uterine environment...

  16. Ice crystallization in ultrafine water-salt aerosols: nucleation, ice-solution equilibrium, and internal structure.

    Science.gov (United States)

    Hudait, Arpa; Molinero, Valeria

    2014-06-04

    Atmospheric aerosols have a strong influence on Earth's climate. Elucidating the physical state and internal structure of atmospheric aqueous aerosols is essential to predict their gas and water uptake, and the locus and rate of atmospherically important heterogeneous reactions. Ultrafine aerosols with sizes between 3 and 15 nm have been detected in large numbers in the troposphere and tropopause. Nanoscopic aerosols arising from bubble bursting of natural and artificial seawater have been identified in laboratory and field experiments. The internal structure and phase state of these aerosols, however, cannot yet be determined in experiments. Here we use molecular simulations to investigate the phase behavior and internal structure of liquid, vitrified, and crystallized water-salt ultrafine aerosols with radii from 2.5 to 9.5 nm and with up to 10% moles of ions. We find that both ice crystallization and vitrification of the nanodroplets lead to demixing of pure water from the solutions. Vitrification of aqueous nanodroplets yields nanodomains of pure low-density amorphous ice in coexistence with vitrified solute rich aqueous glass. The melting temperature of ice in the aerosols decreases monotonically with an increase of solute fraction and decrease of radius. The simulations reveal that nucleation of ice occurs homogeneously at the subsurface of the water-salt nanoparticles. Subsequent ice growth yields phase-segregated, internally mixed, aerosols with two phases in equilibrium: a concentrated water-salt amorphous mixture and a spherical cap-like ice nanophase. The surface of the crystallized aerosols is heterogeneous, with ice and solution exposed to the vapor. Free energy calculations indicate that as the concentration of salt in the particles, the advance of the crystallization, or the size of the particles increase, the stability of the spherical cap structure increases with respect to the alternative structure in which a core of ice is fully surrounded by

  17. ERC initiatives to reduce the burden of cardiac arrest: the European Cardiac Arrest Awareness Day.

    Science.gov (United States)

    Georgiou, Marios; Lockey, Andrew S

    2013-09-01

    The rate of survival from out-of-hospital cardiac arrest in Europe remains unacceptably low and could be increased by better bystander cardiopulmonary resuscitation (CPR) rates. The European Resuscitation Council has announced that there will be a European Cardiac Arrest Awareness Day every year on the 16th of October. This is to coincide with the goals of the Written Declaration passed by the European Parliament in June 2012 that emphasised the importance of equal access to CPR and automated external defibrillator (AED) training. The topic of this year's Awareness Day is 'Children Saving Lives' and it is hoped that all national resuscitation councils will promote awareness of the benefits of training all children in CPR and AED use and lobby for legislative change to ensure that all children receive this training. Children are not just the adults of tomorrow - they are the lifesavers of today and tomorrow. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Prehospital cardiac arrest survival and neurologic recovery.

    Science.gov (United States)

    Hillis, M; Sinclair, D; Butler, G; Cain, E

    1993-01-01

    Many studies of prehospital defibrillation have been conducted but the effects of airway intervention are unknown and neurologic follow-up has been incomplete. A non-randomized cohort prospective study was conducted to determine the effectiveness of defibrillation in prehospital cardiac arrest. Two ambulance companies in the study area developed a defibrillation protocol and they formed the experimental group. A subgroup of these patients received airway management with an esophageal obturator airway (EOA) or endotracheal intubation (ETT). The control group was composed of patients who suffered a prehospital cardiac arrest and did not receive prehospital defibrillation. All survivors were assessed for residual deficits using the Sickness Impact Profile (SIP) and the Dementia Rating Scale (DRS). A total of 221 patients were studied over a 32-month period. Both the experimental group (N = 161) and the control group (N = 60) were comparable with respect to age, sex distribution, and ambulance response time. Survival to hospital discharge was 2/60 (3.3%) in the control group and 12/161 (6.3%) in the experimental group. This difference is not statistically significant. Survival in the experimental group by airway management technique was basic airway support (3/76 3.9%), EOA (3/67 4.5%), and ETT (6/48 12.5%). The improved effect on survival by ETT management was statistically significant. Survivors had minor differences in memory, work, and recreation as compared to ischemic heart disease patients as measured by the SIP and DRS. No effect of defibrillation was found on survival to hospital discharge. However, endotracheal intubation improved survival in defibrillated patients. Survivors had a good functional outcome.

  19. Characterization of a Novel Water Pocket Inside the Human Cx26 Hemichannel Structure

    Science.gov (United States)

    Araya-Secchi, Raul; Perez-Acle, Tomas; Kang, Seung-gu; Huynh, Tien; Bernardin, Alejandro; Escalona, Yerko; Garate, Jose-Antonio; Martínez, Agustin D.; García, Isaac E.; Sáez, Juan C.; Zhou, Ruhong

    2014-01-01

    Connexins (Cxs) are a family of vertebrate proteins constituents of gap junction channels (GJCs) that connect the cytoplasm of adjacent cells by the end-to-end docking of two Cx hemichannels. The intercellular transfer through GJCs occurs by passive diffusion allowing the exchange of water, ions, and small molecules. Despite the broad interest to understand, at the molecular level, the functional state of Cx-based channels, there are still many unanswered questions regarding structure-function relationships, perm-selectivity, and gating mechanisms. In particular, the ordering, structure, and dynamics of water inside Cx GJCs and hemichannels remains largely unexplored. In this work, we describe the identification and characterization of a believed novel water pocket—termed the IC pocket—located in-between the four transmembrane helices of each human Cx26 (hCx26) monomer at the intracellular (IC) side. Using molecular dynamics (MD) simulations to characterize hCx26 internal water structure and dynamics, six IC pockets were identified per hemichannel. A detailed characterization of the dynamics and ordering of water including conformational variability of residues forming the IC pockets, together with multiple sequence alignments, allowed us to propose a functional role for this cavity. An in vitro assessment of tracer uptake suggests that the IC pocket residue Arg-143 plays an essential role on the modulation of the hCx26 hemichannel permeability. PMID:25099799

  20. Structural integrity investigation for RPV with various cooling water levels under pressurized melting pool

    Directory of Open Access Journals (Sweden)

    J. Mao

    2018-03-01

    Full Text Available The strategy denoted as in-vessel retention (IVR is widely used in severe accident (SA management by most advanced nuclear power plants. The essence of IVR mitigation is to provide long-term external water cooling in maintaining the reactor pressure vessel (RPV integrity. Actually, the traditional IVR concept assumed that RPV was fully submerged into the water flooding, and the melting pool was depressurized during the SA. The above assumptions weren't seriously challenged until the occurrence of Fukushima accident on 2011, suggesting the structural behavior had not been appropriately assessed. Therefore, the paper tries to address the structure-related issue on determining whether RPV safety can be maintained or not with the effect of various water levels and internal pressures created from core meltdown accident. In achieving it, the RPV structural behaviors are numerically investigated in terms of several field parameters, such as temperature, deformation, stress, plastic strain, creep strain, and total damage. Due to the presence of high temperature melt on the inside and water cooling on the outside, the RPV failure is governed by the failure mechanisms of creep, thermal-plasticity and plasticity. The creep and plastic damages are interacted with each other, which further accelerate the failure process. Through detailed investigation, it is found that the internal pressure as well as water levels plays an important role in determining the RPV failure time, mode and site.

  1. The influence of Critical Zone structure on runoff paths, seasonal water storage, and ecosystem composition

    Science.gov (United States)

    Hahm, W. J.; Dietrich, W. E.; Rempe, D.; Dralle, D.; Dawson, T. E.; Lovill, S.; Bryk, A.

    2017-12-01

    Understanding how subsurface water storage mediates water availability to ecosystems is crucial for elucidating linkages between water, energy, and carbon cycles from local to global scales. Earth's Critical Zone (the CZ, which extends from the top of the vegetation canopy downward to fresh bedrock) includes fractured and weathered rock layers that store and release water, thereby contributing to ecosystem water supplies, and yet are not typically represented in land-atmosphere models. To investigate CZ structural controls on water storage dynamics, we intensively studied field sites in a Mediterranean climate where winter rains arrive months before peak solar energy availability, resulting in strong summertime ecosystem reliance on stored subsurface water. Intra-hillslope and catchment-wide observations of CZ water storage capacity across a lithologic boundary in the Franciscan Formation of the Northern California Coast Ranges reveal large differences in the thickness of the CZ and water storage capacity that result in a stark contrast in plant community composition and stream behavior. Where the CZ is thick, rock moisture storage supports forest transpiration and slow groundwater release sustains baseflow and salmon populations. Where the CZ is thin, limited water storage is used by an oak savanna ecosystem, and streams run dry in summer due to negligible hillslope drainage. At both sites, wet season precipitation replenishes the dynamic storage deficit generated during the summer dry season, with excess winter rains exiting the watersheds via storm runoff as perched groundwater fracture flow at the thick-CZ site and saturation overland flow at the thin-CZ site. Annual replenishment of subsurface water storage even in severe drought years may lead to ecosystem resilience to climatic perturbations: during the 2011-2015 drought there was not widespread forest die-off in the study area.

  2. 76 FR 43230 - National Pollutant Discharge Elimination System-Cooling Water Intake Structures at Existing...

    Science.gov (United States)

    2011-07-20

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 122 and 125 [EPA-HQ-OW-2008-0667, FRL-9441-8] RIN 2040-AE95 National Pollutant Discharge Elimination System--Cooling Water Intake Structures at Existing Facilities and Phase I Facilities AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule...

  3. Sonneratiaceae (concluded). Sonneratiaceae and other mangrove-swamp families, anatomical structure and water relations

    NARCIS (Netherlands)

    Reinders-Gouwentak, C.A.

    1948-01-01

    The question whether tidal and non-tidal members of a family have a separate wood anatomical structure would be examined best in such genera as embrace both types. The sequel to this examination, whether any such differences are connected with peculiarities in the water relations of the plants,

  4. Atomic-scale structures of interfaces between phyllosilicate edges and water

    NARCIS (Netherlands)

    Liu, X.; Lu, X.; Meijer, E.J.; Wang, R.; Zhou, H.

    2012-01-01

    We report first-principles molecular dynamics (FPMD) studies on the structures of interfaces between phyllosilicate edges and water. Using FPMD, the substrates and solvents are simulated at the same first-principles level, and the thermal motions are sampled via molecular dynamics. Both the neutral

  5. Institutional and structural barriers for implementing on-farm water saving irrigation systems

    DEFF Research Database (Denmark)

    Pedersen, Søren Marcus; Boesen, Mads Vejlby; Ørum, Jens Erik

    2013-01-01

    institutional and structural barriers for shifting to more water efficient technologies on farms. To deal with the lack of incentives, a holistic and multidisciplinary assessment approach has been taken to cover the various parameters that may influence farmers' choice of technology. A case study analysis has...

  6. Animal Hairs as Water-stimulated Shape Memory Materials: Mechanism and Structural Networks in Molecular Assemblies

    Science.gov (United States)

    Xiao, Xueliang; Hu, Jinlian

    2016-05-01

    Animal hairs consisting of α-keratin biopolymers existing broadly in nature may be responsive to water for recovery to the innate shape from their fixed deformation, thus possess smart behavior, namely shape memory effect (SME). In this article, three typical animal hair fibers were first time investigated for their water-stimulated SME, and therefrom to identify the corresponding net-points and switches in their molecular and morphological structures. Experimentally, the SME manifested a good stability of high shape fixation ratio and reasonable recovery rate after many cycles of deformation programming under water stimulation. The effects of hydration on hair lateral size, recovery kinetics, dynamic mechanical behaviors and structural components (crystal, disulfide and hydrogen bonds) were then systematically studied. SME mechanisms were explored based on the variations of structural components in molecular assemblies of such smart fibers. A hybrid structural network model with single-switch and twin-net-points was thereafter proposed to interpret the water-stimulated shape memory mechanism of animal hairs. This original work is expected to provide inspiration for exploring other natural materials to reveal their smart functions and natural laws in animals including human as well as making more remarkable synthetic smart materials.

  7. Destabilization of the hydrogen-bond structure of water by the osmolyte trimethylamine N-oxide

    NARCIS (Netherlands)

    Rezus, Y.L.A.; Bakker, H.J.

    2009-01-01

    We use femtosecond mid-infrared pump−probe spectroscopy to investigate the effects of the osmolyte trimethylamine N-oxide (TMAO) on the structural dynamics of water. As a comparison, we also investigate the effects of other amphiphilic molecules: tetramethylurea (TMU), urea, proline, and

  8. Water hammer with fluid-structure interaction in thick-walled pipes

    NARCIS (Netherlands)

    Tijsseling, A.S.

    2007-01-01

    A one-dimensional mathematical model is presented which describes the acoustic behaviour of thick-walled liquid-filled pipes. The model is based on conventional water-hammer and beam theories. Fluid–structure interaction (FSI) is taken into account. The equations governing straight pipes are derived

  9. Structure and stability of triglyceride monolayers on water and mica surfaces

    NARCIS (Netherlands)

    Zdravkova, A.N.; van der Eerden, J.P.J.M.

    2007-01-01

    The structure and the stability of tripalmitin (PPP), tristearin (SSS), and triarachidin (AAA) monolayers at the air-water interface are investigated with the Langmuir method. The Langmuir-Blodgett (LB) layers obtained by deposition on mica were investigated with atomic force microscopy (AFM). Our

  10. The effect of water content on the magnetic and structural properties of goethite

    International Nuclear Information System (INIS)

    Betancur, J.D.; Barrero, C.A.; Greneche, J.M.; Goya, G.F.

    2004-01-01

    We have studied the effect of water content on the magnetic and structural properties of goethite. For that purpose, four samples were prepared using two different hydrothermal methods, one of them is derived on the Fe(II) precursors and the other one from Fe(III) precursors. The samples were characterized by X-ray diffraction (XRD), TGA, BET, FTIR, Moessbauer spectrometry at RT, 77 and 4.2 K and ZFC and FC curves. The results suggest that the goethites from the Fe(II) precursors are less crystalline, have higher water contents and do not show magnetic ordered structure at RT in comparison to the goethites from the Fe(III) precursors. The goethites from the last systems exhibit good crystallinity, low water content and magnetic ordering at room temperature. Our results suggest that both structural and adsorbed water contents reduce the magnetic hyperfine field at 4.2 K. A linear correlation with regression coefficient of 0.91 between the saturation hyperfine field and both the structural hydroxyl content and the surface area could be derived

  11. Designing robust alumina nanowires-on-nanopores structures: superhydrophobic surfaces with slippery or sticky water adhesion.

    Science.gov (United States)

    Peng, Shan; Tian, Dong; Miao, Xinrui; Yang, Xiaojun; Deng, Wenli

    2013-11-01

    Hierarchical alumina surfaces with different morphologies were fabricated by a simple one-step anodization method. These alumina films were fabricated by a new raw material: silica gel plate (aluminum foil with a low purity of 97.17%). The modulation of anodizing time enabled the formation of nanowires-on-nanopores hybrid nanostructures having controllable nanowires topographies through a self-assembly process. The resultant structures were demonstrated to be able to achieve superhydrophobicity without any hydrophobic coating layer. More interestingly, it is found that the as-prepared superhydrophobic alumina surfaces exhibited high contrast water adhesion. Hierarchical alumina film with nanowire bunches-on-nanopores (WBOP) morphology presents extremely slippery property which can obtain a sliding angle (SA) as low as 1°, nanowire pyramids-on-nanopores (WPOP) structure shows strongly sticky water adhesion with the adhesive ability to support 15 μL inverted water droplet at most. The obtained superhydrophobic alumina surfaces show remarkable mechanical durability even treated by crimping or pressing without impact on the water-repellent performance. Moreover, the created surfaces also show excellent resistivity to ice water, boiling water, high temperature, organic solvent and oil contamination, which could expand their usefulness and efficacy in harsh conditions. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Growth-arrest-specific protein 2 inhibits cell division in Xenopus embryos.

    Directory of Open Access Journals (Sweden)

    Tong Zhang

    Full Text Available Growth-arrest-specific 2 gene was originally identified in murine fibroblasts under growth arrest conditions. Furthermore, serum stimulation of quiescent, non-dividing cells leads to the down-regulation of gas2 and results in re-entry into the cell cycle. Cytoskeleton rearrangements are critical for cell cycle progression and cell division and the Gas2 protein has been shown to co-localize with actin and microtubules in interphase mammalian cells. Despite these findings, direct evidence supporting a role for Gas2 in the mechanism of cell division has not been reported.To determine whether the Gas2 protein plays a role in cell division, we over-expressed the full-length Gas2 protein and Gas2 truncations containing either the actin-binding CH domain or the tubulin-binding Gas2 domain in Xenopus laevis embryos. We found that both the full-length Gas2 protein and the Gas2 domain, but not the CH domain, inhibited cell division and resulted in multinucleated cells. The observation that Gas2 domain alone can arrest cell division suggests that Gas2 function is mediated by microtubule binding. Gas2 co-localized with microtubules at the cell cortex of Gas2-injected Xenopus embryos using cryo-confocal microscopy and co-sedimented with microtubules in cytoskeleton co-sedimentation assays. To investigate the mechanism of Gas2-induced cell division arrest, we showed, using a wound-induced contractile array assay, that Gas2 stabilized microtubules. Finally, electron microscopy studies demonstrated that Gas2 bundled microtubules into higher-order structures.Our experiments show that Gas2 inhibits cell division in Xenopus embryos. We propose that Gas2 function is mediated by binding and bundling microtubules, leading to cell division arrest.

  13. Encapsulating fly ash and acidic process waste water in brick structure

    International Nuclear Information System (INIS)

    Koseoglu, K.; Polat, M.; Polat, H.

    2010-01-01

    Fly ash contains metals such as cadmium, iron, lead, aluminum and zinc in its structure in appreciable amounts. These metals can leach out into surface and ground waters if fly ash is not properly disposed of. A similar problem also exists for acidic process waste waters discharged by numerous industries. The purpose of this study was to utilize such wastes as additives in the production of construction quality bricks for the purpose of waste elimination. The bricks produced were subjected to flexural strength and water retention capacity tests along with heavy metal leaching experiments in order to determine the applicability of the procedure and the best possible recipes. This paper summarizes the results obtained in these tests along with the possible mechanisms involved in stabilizing the two wastes in the brick structure.

  14. Income, Economic Structure and Trade: Impacts on Recent Water Use Trends in the European Union

    Directory of Open Access Journals (Sweden)

    Rosa Duarte

    2018-01-01

    Full Text Available From the mid-1990s to the recent international economic crisis, the European Union (EU27 experienced a significant economic growth and a flat population increase. During these years, the water resources directly used by the EU countries displayed a growing but smooth trend. However, European activities intensively demanded water resources throughout the whole global supply chain. The growth rate of embodied water use was three times higher than the growth in water directly used by these economies. This was mainly due to the large upsurge of virtual water imports in the EU (e.g., about 25% of the change in water imports in the world was directly linked to the increasing imports in the EU27 countries. In this context, we analyze water use changes in the EU27 from 1995 to 2009, combining the production and consumption perspectives. To that aim, we use the environmentally extended input-output approach to obtain the volume of water embodied in domestic production and in trade flows at the sector and country levels. In the empirical analysis, we utilize multi-regional input-output data from the World Input Output Database. In addition, by means of a structural decomposition analysis we identify and quantify the factors explaining changes in these trends. We focus both on the role of domestic production and trade and estimate the associated intensity, technology and scale effects. This analysis is done for different clusters, identifying singular patterns depending on income criteria. Our results confirm the boost of demand growth in that period, the positive but negligible effect of structural change, and the decline in water intensity which, however, was not enough to compensate the effects on water associated to the economic expansion in the period. These findings also point at a gradual substitution of domestic water use for virtual water imports. More concretely, in most countries the food industry tended to reduce its backward linkages with the

  15. Protonic charge defect structures in floating water bridges observed as Zundel and Eigen solvation arrangements

    Science.gov (United States)

    Teschke, Omar; de Castro, Jose Roberto; Valente Filho, Juracyr Ferraz; Soares, David Mendez

    2017-10-01

    Protonic arrangements were detected in water bridge structures using confocal Raman microscopy, and the spectra show two formed structures. The measured Raman spectra were modified using the voltage applied to the bridge structure, which changed the proportion of these two species. Initially, for a 6.3 kV applied voltage, there was a measurable increase in the bridge current above the Ohmic contribution and the observed Raman spectrum of this new injected specie corresponded to the computed spectrum for the Zundel protonic arrangement. As the voltage further increases a contribution from the Eigen proton solvation specie is added to the measured spectrum.

  16. Effects of cathodic protection potential and stress ratio on fatigue thresholds of structured steels in sea water

    Energy Technology Data Exchange (ETDEWEB)

    Dolphin, A.S.; Tice, D.R.

    1987-09-01

    The results reported here suggest that the very high thresholds found under reducing {Delta}K conditions may be inapplicable under the increasing {Delta}K conditions likely to be more relevant to real structures. This conclusion is based on just two tests at - 0.85V SCE, and so requires confirmation over a range of R ratios and at free corrosion and overprotection potentials. Crack growth thresholds appear to be higher under cathodic over-protection conditions (-1.05V SCE) than at more positive potentials, due to calcareous scale formation. Tests at negative R ratios are required to ensure this calcareous scale would remain intact under compressive loading. Due to the large observed influence of calcareous scale on crack growth, and particularly on the arrest of growing cracks, more detailed microstructural examination is recommended on the specimens tested in this programme. (author).

  17. Microscopic dynamics of water around unfolded structures of barstar at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Somedatta; Chakraborty, Kaushik; Khatua, Prabir; Bandyopadhyay, Sanjoy, E-mail: sanjoy@chem.iitkgp.ernet.in [Molecular Modeling Laboratory, Department of Chemistry, Indian Institute of Technology, Kharagpur 721302 (India)

    2015-02-07

    The breaking of the native structure of a protein and its influences on the dynamic response of the surrounding solvent is an important issue in protein folding. In this work, we have carried out atomistic molecular dynamics simulations to unfold the protein barstar at two different temperatures (400 K and 450 K). The two unfolded forms obtained at such high temperatures are further studied at room temperature to explore the effects of nonuniform unfolding of the protein secondary structures along two different pathways on the microscopic dynamical properties of the surface water molecules. It is demonstrated that though the structural transition of the protein in general results in less restricted water motions around its segments, but there are evidences of formation of new conformational motifs upon unfolding with increasingly confined environment around them, thereby resulting in further restricted water mobility in their hydration layers. Moreover, it is noticed that the effects of nonuniform unfolding of the protein segments on the relaxation times of the protein–water (PW) and the water–water (WW) hydrogen bonds are correlated with hindered hydration water motions. However, the kinetics of breaking and reformation of such hydrogen bonds are found to be influenced differently at the interface. It is observed that while the effects of unfolding on the PW hydrogen bond kinetics seem to be minimum, but the kinetics involving the WW hydrogen bonds around the protein segments exhibit noticeably heterogeneous characteristics. We believe that this is an important observation, which can provide valuable insights on the origin of heterogeneous influence of unfolding of a protein on the microscopic properties of its hydration water.

  18. Structural Modifications of Fructans in Aloe barbadensis Miller (Aloe Vera) Grown under Water Stress.

    Science.gov (United States)

    Salinas, Carlos; Handford, Michael; Pauly, Markus; Dupree, Paul; Cardemil, Liliana

    2016-01-01

    Aloe barbadensis Miller (Aloe vera) has a Crassulaceae acid metabolism which grants the plant great tolerance to water restrictions. Carbohydrates such as acemannans and fructans are among the molecules responsible for tolerating water deficit in other plant species. Nevertheless, fructans, which are prebiotic compounds, have not been described nor studied in Aloe vera, whose leaf gel is known to possess beneficial pharmaceutical, nutritional and cosmetic properties. As Aloe vera is frequently cultivated in semi-arid conditions, like those found in northern Chile, we investigated the effect of water deficit on fructan composition and structure. For this, plants were subjected to different irrigation regimes of 100%, 75%, 50% and 25% field capacity (FC). There was a significant increase in the total sugars, soluble sugars and oligo and polyfructans in plants subjected to water deficit, compared to the control condition (100% FC) in both leaf tips and bases. The amounts of fructans were also greater in the bases compared to the leaf tips in all water treatments. Fructans also increase in degree of polymerization with increasing water deficit. Glycosidic linkage analyses by GC-MS, led to the conclusion that there are structural differences between the fructans present in the leaves of control plants with respect to plants irrigated with 50% and 25% FC. Therefore, in non-stressed plants, the inulin, neo-inulin and neo-levan type of fructans predominate, while in the most stressful conditions for the plant, Aloe vera also synthesizes fructans with a more branched structure, the neofructans. To our knowledge, the synthesis and the protective role of neo-fructans under extreme water deficit has not been previously reported.

  19. Structural and energetic properties of La3+ in water/DMSO mixtures

    Science.gov (United States)

    Montagna, Maria; Spezia, Riccardo; Bodo, Enrico

    2017-11-01

    By using molecular dynamics based on a custom polarizable force field, we have studied the solvation of La3+ in an equimolar mixture of dimethylsulfoxide (DMSO) with water. An extended structural analysis has been performed to provide a complete picture of the physical properties at the basis of the interaction of La3+ with both solvents. Through our simulations we found that, very likely, the first solvation shell in the mixture is not unlike the one found in pure water or pure DMSO and contains 9 solvent molecules. We have also found that the solvation is preferentially due to DMSO molecules with the water initially present in first shell quickly leaving to the bulk. The dehydration process of the first shell has been analyzed by both plain MD simulations and a constrained dynamics approach; the free energy profiles for the extraction of water from first shell have also been computed.

  20. SFG study on potential-dependent structure of water at Pt electrode/electrolyte solution interface

    Energy Technology Data Exchange (ETDEWEB)

    Noguchi, Hidenori; Okada, Tsubasa; Uosaki, Kohei [Physical Chemistry Laboratory, Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo 060-0810 (Japan)

    2008-10-01

    Structure of water at Pt/electrolyte solution interface was investigated by sum frequency generation (SFG) spectroscopy. Two broad peaks were observed in OH stretching region at ca. 3200 cm{sup -1} and ca. 3400 cm{sup -1}, which are known to be due to the symmetric OH stretching (U{sub 1}) of tetrahedrally coordinated, i.e., strongly hydrogen bonded 'ice-like' water, and the asymmetric OH stretching (U{sub 3}) of water molecules in a more random arrangement, i.e., weakly hydrogen bonded 'liquid-like' water, respectively. The SFG intensity strongly depended on electrode potential. Several possibilities are suggested for the potential dependence of the SFG intensity. (author)

  1. Structural Arrangement of Water Molecules around Highly Charged Nanoparticles: Molecular Dynamics Simulation

    International Nuclear Information System (INIS)

    Kim, Eunae; Yeom, Min Sun

    2014-01-01

    Molecular dynamics simulations were performed to understand the structural arrangement of water molecules around highly charged nanoparticles under aqueous conditions. The effect of two highly charged nanoparticles on the solvation charge asymmetry has been examined. We calculated the radial distribution functions of the components of water molecules around nanoparticles which have four charge types at two different salt concentrations. Even though the distributions of water molecules surrounding a sodium ion and a chloride ion are hardly affected by the charges of nanoparticles and the salt concentrations, those around highly charged nanoparticles are strongly influenced by the charges of nanoparticles, but hardly by the charges of nanoparticles and salt concentrations. We find that the distributions of hydrogen atoms in water molecules around one highly charged nanoparticle are dependent on the magnitude of the nanoparticle charge

  2. Structure and crystallinity of water dispersible photoactive nanoparticles for organic solar cells

    DEFF Research Database (Denmark)

    Pedersen, Emil Bøje Lind; Pedersen, M.C.; Simonsen, Søren Bredmose

    2015-01-01

    Water based inks would be a strong advantage for large scale production of organic photovoltaic devices. Formation of water dispersible nanoparticles produced by the Landfester method is a promising route to achieve such inks. We provide new insights into the key ink properties of poly(3-hexylthi......Water based inks would be a strong advantage for large scale production of organic photovoltaic devices. Formation of water dispersible nanoparticles produced by the Landfester method is a promising route to achieve such inks. We provide new insights into the key ink properties of poly(3......-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) nanoparticles such as the internal structure and crystallinity of the dispersed nanoparticles and the previously unreported drastic changes that occur when the inks are cast into a film. We observe through transmission electron...

  3. Multi-frequency complex network from time series for uncovering oil-water flow structure.

    Science.gov (United States)

    Gao, Zhong-Ke; Yang, Yu-Xuan; Fang, Peng-Cheng; Jin, Ning-De; Xia, Cheng-Yi; Hu, Li-Dan

    2015-02-04

    Uncovering complex oil-water flow structure represents a challenge in diverse scientific disciplines. This challenge stimulates us to develop a new distributed conductance sensor for measuring local flow signals at different positions and then propose a novel approach based on multi-frequency complex network to uncover the flow structures from experimental multivariate measurements. In particular, based on the Fast Fourier transform, we demonstrate how to derive multi-frequency complex network from multivariate time series. We construct complex networks at different frequencies and then detect community structures. Our results indicate that the community structures faithfully represent the structural features of oil-water flow patterns. Furthermore, we investigate the network statistic at different frequencies for each derived network and find that the frequency clustering coefficient enables to uncover the evolution of flow patterns and yield deep insights into the formation of flow structures. Current results present a first step towards a network visualization of complex flow patterns from a community structure perspective.

  4. The structure of liquid water by polarized neutron diffraction and reverse Monte Carlo modelling.

    Science.gov (United States)

    Temleitner, László; Pusztai, László; Schweika, Werner

    2007-08-22

    The coherent static structure factor of water has been investigated by polarized neutron diffraction. Polarization analysis allows us to separate the huge incoherent scattering background from hydrogen and to obtain high quality data of the coherent scattering from four different mixtures of liquid H(2)O and D(2)O. The information obtained by the variation of the scattering contrast confines the configurational space of water and is used by the reverse Monte Carlo technique to model the total structure factors. Structural characteristics have been calculated directly from the resulting sets of particle coordinates. Consistency with existing partial pair correlation functions, derived without the application of polarized neutrons, was checked by incorporating them into our reverse Monte Carlo calculations. We also performed Monte Carlo simulations of a hard sphere system, which provides an accurate estimate of the information content of the measured data. It is shown that the present combination of polarized neutron scattering and reverse Monte Carlo structural modelling is a promising approach towards a detailed understanding of the microscopic structure of water.

  5. Influence of cholesterol and ceramide VI on the structure of multilamellar lipid membranes at water exchange

    International Nuclear Information System (INIS)

    Ryabova, N. Yu.; Kiselev, M. A.; Balagurov, A. M.

    2010-01-01

    The structural changes in the multilamellar lipid membranes of dipalmitoylphosphatidylcholine (DPPC)/cholesterol and DPPC/ceramide VI binary systems during hydration and dehydration have been studied by neutron diffraction. The effect of cholesterol and ceramide on the kinetics of water exchange in DPPC membranes is characterized. Compared to pure DPPC, membranes of binary systems swell faster during hydration (with a characteristic time of ∼30 min). Both compounds, ceramide VI and cholesterol, similarly affect the hydration of DPPC membranes, increasing the repeat distance due to the bilayer growth. However, in contrast to cholesterol, ceramide significantly reduces the thickness of the membrane water layer. The introduction of cholesterol into a DPPC membrane slows down the change in the parameters of the bilayer internal structure during dehydration. In the DPPC/ceramide VI/cholesterol ternary system (with a molar cholesterol concentration of 40%), cholesterol is partially released from the lamellar membrane structure into the crystalline phase.

  6. Multistep Cylindrical Structure Analysis at Normal Incidence Based on Water-Substrate Broadband Metamaterial Absorbers

    Science.gov (United States)

    Fang, Chonghua

    2018-01-01

    A new multistep cylindrical structure based on water-substrate broadband metamaterial absorbers is designed to reduce the traditional radar cross-section (RCS) of a rod-shaped object. The proposed configuration consists of two distinct parts. One of these components is formed by a four-step cylindrical metal structure, whereas the other one is formed by a new water-substrate broadband metamaterial absorber. The designed structure can significantly reduce the radar cross section more than 10 dB from 4.58 to 18.42 GHz which is the 86.5 % bandwidth of from C-band to 20 GHz. The results of measurement show reasonably good accordance with the simulated ones, which verifies the ability and effect of the proposed design.

  7. Slowing the Starch Digestion by Structural Modification through Preparing Zein/Pectin Particle Stabilized Water-in-Water Emulsion.

    Science.gov (United States)

    Chen, Jia-Feng; Guo, Jian; Zhang, Tao; Wan, Zhi-Li; Yang, Juan; Yang, Xiao-Quan

    2018-04-25

    Slowing the digestion of starch is one of the dominant concerns in the food industry. A colloidal structural modification strategy for solving this problem was proposed in this work. Due to thermodynamic incompatibility between two biopolymers, water/water emulsion of waxy corn starch (WCS) droplets dispersed in a continuous aqueous guar gum (GG) was prepared, and zein particles (ZPs), obtained by antisolvent precipitation and pectin modification, were used as stabilizer. As the ratio of zein to pectin in the particles was 1:1, their wetting properties in the two polysaccharides were similar, which made them accumulate at the interface and cover the WCS-rich droplets. The analysis of digestibility curves indicated that a rapid (rate constant k 1 : 0.145 min -1 ) and a slow phase ( k 2 : 0.022 min -1 ) existed during WCS digestion. However, only one slow phase ( k 2 : 0.019 min -1 ) was found in the WCS/GG emulsion, suggesting that this structure was effective in slowing starch digestion.

  8. Regulation of Silk Material Structure by Temperature-Controlled Water Vapor Annealing

    Science.gov (United States)

    Hu, Xiao; Shmelev, Karen; Sun, Lin; Gil, Eun-Seok; Park, Sang-Hyug; Cebe, Peggy; Kaplan, David L.

    2011-01-01

    We present a simple and effective method to obtain refined control of the molecular structure of silk biomaterials through physical temperature-controlled water vapor annealing (TCWVA). The silk materials can be prepared with control of crystallinity, from a low content using conditions at 4°C (alpha-helix dominated silk I structure), to highest content of ~60% crystallinity at 100°C (beta-sheet dominated silk II structure). This new physical approach covers the range of structures previously reported to govern crystallization during the fabrication of silk materials, yet offers a simpler, green chemistry, approach with tight control of reproducibility. The transition kinetics, thermal, mechanical, and biodegradation properties of the silk films prepared at different temperatures were investigated and compared by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), uniaxial tensile studies, and enzymatic degradation studies. The results revealed that this new physical processing method accurately controls structure, in turn providing control of mechanical properties, thermal stability, enzyme degradation rate, and human mesenchymal stem cell interactions. The mechanistic basis for the control is through the temperature controlled regulation of water vapor, to control crystallization. Control of silk structure via TCWVA represents a significant improvement in the fabrication of silk-based biomaterials, where control of structure-property relationships is key to regulating material properties. This new approach to control crystallization also provides an entirely new green approach, avoiding common methods which use organic solvents (methanol, ethanol) or organic acids. The method described here for silk proteins would also be universal for many other structural proteins (and likely other biopolymers), where water controls chain interactions related to material properties. PMID:21425769

  9. The structure of the pelagic food web in relation to water column structure in the Skagerrak

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Kaas, H.; Kruse, B.

    1990-01-01

    by a doming of the pycnocline, with a deep mixed layer along the periphery and a very shallow pycnocline in central parts. Average phytoplankton size increased with the depth of the upper mixed layer, and the central stratified area was characterized by small flagellates while large and chain-forming diatoms...... on particle surface area rather than particle volume or chl a, and showed a distributional pattern that was nearly the inverse of the distribution of copepod activity. That is, peak bacterial growth rates occurred in central, stratified parts and lower rates were found along the margin with a deep mixed layer....... Thus a 'microbial loop' type of food web seemed to be evolving in the central, strongly stratified parts of the Skagerrak, while a shorter 'classical' type of food web appeared to dominate along the margin. The relation between food web structure and vertical mixing processes observed on oceanwide...

  10. Design Concept of Dialyzer Biomaterials: How to Find Biocompatible Polymers Based on the Biointerfacial Water Structure.

    Science.gov (United States)

    Tanaka, Masaru

    2017-01-01

    Although various types of materials have been used widely in dialyzers, most biomaterials lack the desired functional properties to interface with blood and have not been engineered for optimum performance. Therefore, there is increasing demand to develop novel materials to address such problems in the dialysis arena. Numerous parameters of polymeric biomaterials can affect biocompatibility in a controlled manner. The mechanisms responsible for the biocompatibility of polymers at the molecular level have not been clearly demonstrated, although many theoretical and experimental efforts have been made to try and understand them. Moreover, water interactions have been recognized as fundamental for the blood response to contact with polymers. We have proposed the 'intermediate water' concept and hypothesized that intermediate water, which prevents the proteins and blood cells from directly contacting the polymer surface, or nonfreezing water on the polymer surface, plays an important role in the biocompatibility of polymers. This chapter provides an overview of the recent experimental progress of biocompatible polymers measured by thermal, spectroscopic, and surface force techniques. Additionally, it highlights recent developments in the use of biocompatible polymeric biomaterials for dialyzers and provides an overview of the progress made in the design of multifunctional biomedical polymers by controlling the biointerfacial water structure through precision polymer synthesis. Key Messages: Intermediate water was found only in hydrated biopolymers (proteins, polysaccharides, and nucleic acids, DNA and RNA) and hydrated biocompatible synthetic polymers. Intermediate water could be one of the main screening factors for the design of appropriate dialyzer materials. © 2017 S. Karger AG, Basel.

  11. Structure of water in mesoporous organosilica by calorimetry and inelastic neutron scattering

    Science.gov (United States)

    Levy, Esthy; Kolesnikov, Alexander I.; Li, Jichen; Mastai, Yitzhak

    2009-01-01

    In this paper, we describe the preparation of mesoporous organosilica samples with hydrophilic or hydrophobic organic functionality inside the silica channel. We synthesized mesoporous organosilica of identical pore sizes based on two different organic surface functionality namely hydrophobic (based on octyltriethoxysilane OTES) and hydrophilic (3-aminopropyltriethoxysilane ATES) and MCM-41 was used as a reference system. The structure of water/ice in those porous silica samples have been investigated over a range temperatures by differential scanning calorimetry (DSC) and inelastic neutron scattering (INS). INS study revealed that water confined in hydrophobic mesoporous organosilica shows vibrational behavior strongly different than bulk water. It consists of two states: water with strong and weak hydrogen bonds (with ratio 1:2.65, respectively), compared to ice-Ih. The corresponding O-O distances in these water states are 2.67 and 2.87 Ǻ, which strongly differ compared to ice-Ih (2.76 Ǻ). INS spectra for water in hydrophilic mesoporous organosilica ATES show behavior similar to bulk water, but with greater degree of disorder.

  12. Bacterial Community Structure Shifted by Geosmin in Granular Activated Carbon System of Water Treatment Plants.

    Science.gov (United States)

    Pham, Ngoc Dung; Lee, Eun-Hee; Chae, Seon-Ha; Cho, Yongdeok; Shin, Hyejin; Son, Ahjeong

    2016-01-01

    We investigated the relation between the presence of geosmin in water and the bacterial community structure within the granular activated carbon (GAC) system of water treatment plants in South Korea. GAC samples were collected in May and August of 2014 at three water treatment plants (Sungnam, Koyang, and Yeoncho in Korea). Dissolved organic carbon and geosmin were analyzed before and after GAC treatment. Geosmin was found in raw water from Sungnam and Koyang water treatment plants but not in that from Yeoncho water treatment plant. Interestingly, but not surprisingly, the 16S rRNA clone library indicated that the bacterial communities from the Sungnam and Koyang GAC systems were closely related to geosmin-degrading bacteria. Based on the phylogenetic tree and multidimensional scaling plot, bacterial clones from GAC under the influence of geosmin were clustered with Variovorax paradoxus strain DB 9b and Comamonas sp. DB mg. In other words, the presence of geosmin in water might have inevitably contributed to the growth of geosmin degraders within the respective GAC system.

  13. Influence of secondary water supply systems on microbial community structure and opportunistic pathogen gene markers.

    Science.gov (United States)

    Li, Huan; Li, Shang; Tang, Wei; Yang, Yang; Zhao, Jianfu; Xia, Siqing; Zhang, Weixian; Wang, Hong

    2018-06-01

    Secondary water supply systems (SWSSs) refer to the in-building infrastructures (e.g., water storage tanks) used to supply water pressure beyond the main distribution systems. The purpose of this study was to investigate the influence of SWSSs on microbial community structure and the occurrence of opportunistic pathogens, the latter of which are an emerging public health concern. Higher numbers of bacterial 16S rRNA genes, Legionella and mycobacterial gene markers were found in public building taps served by SWSSs relative to the mains, regardless of the flushing practice (P water retention time, warm temperature and loss of disinfectant residuals promoted microbial growth and colonization of potential pathogens in SWSSs. Varied levels of microbial community shifts were found in different types of SWSSs during water transportation from the distribution main to taps, highlighting the critical role of SWSSs in shaping the drinking water microbiota. Overall, the results provided insight to factors that might aid in controlling pathogen proliferation in real-world water systems using SWSSs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Geostatistical investigation into the temporal evolution of spatial structure in a shallow water table

    Directory of Open Access Journals (Sweden)

    S. W. Lyon

    2006-01-01

    Full Text Available Shallow water tables near-streams often lead to saturated, overland flow generating areas in catchments in humid climates. While these saturated areas are assumed to be principal biogeochemical hot-spots and important for issues such as non-point pollution sources, the spatial and temporal behavior of shallow water tables, and associated saturated areas, is not completely understood. This study demonstrates how geostatistical methods can be used to characterize the spatial and temporal variation of the shallow water table for the near-stream region. Event-based and seasonal changes in the spatial structure of the shallow water table, which influences the spatial pattern of surface saturation and related runoff generation, can be identified and used in conjunction to characterize the hydrology of an area. This is accomplished through semivariogram analysis and indicator kriging to produce maps combining soft data (i.e., proxy information to the variable of interest representing general shallow water table patterns with hard data (i.e., actual measurements that represent variation in the spatial structure of the shallow water table per rainfall event. The area used was a hillslope in the Catskill Mountains region of New York State. The shallow water table was monitored for a 120 m×180 m near-stream region at 44 sampling locations on 15-min intervals. Outflow of the area was measured at the same time interval. These data were analyzed at a short time interval (15 min and at a long time interval (months to characterize the changes in the hydrologic behavior of the hillslope. Indicator semivariograms based on binary-transformed ground water table data (i.e., 1 if exceeding the time-variable median depth to water table and 0 if not were created for both short and long time intervals. For the short time interval, the indicator semivariograms showed a high degree of spatial structure in the shallow water table for the spring, with increased range

  15. The structural and dynamic characteristics of a water-polimer high-speed jet

    Directory of Open Access Journals (Sweden)

    Андрій Володимирович Погребняк

    2017-07-01

    Full Text Available The aim is to study the structural and dynamic characteristics of the water-polymer jet, what is of decisive importance for understanding the nature of the abnormally high cutting ability. A complex study of the structure and dynamics of a water-polymer high-speed jet has been carried out. Analysis of the photographs of jets of aqueous PEO solution indicates that adding polyethylene oxide (PEO into water results in a significant increase in the initial sections of the water-polymer jet, which characterizes the quality of its formation, and leads to compactness due to a reduction of its diameter. The obtained experimental data made it possible to propose a relationship for determining the dimensionless value of the initial sections of jets of aqueous PEO solutions of different concentration and molecular mass of PEO, taking into account the real parameters of the jet forming head. Investigation of changes in the energy capabilities of water-polymer jets, which were estimated by the force of the jet impact on the steel obstacle, made it possible to establish the features of their dynamics. The obtained experimental data explain the nature of the change in the cutting properties of the water-polymer jet as a function of the distance between the surface of the material that is being cut and the cut of the nozzle. If the distance from the nozzle to the surface of the material is less than the size of the initial sections of the water-polymer jet, an increase in the diameter of the nozzle outlet hole will lead to a reduction in the depth of the cut. If, however, the distance from the nozzle to the surface of the material approaches or exceeds the size of the main part of the water-polymer jet, then the depth of the cut will increase with increasing diameter of the nozzle at a constant pressure. The use of structural and dynamic characteristics of water-polymer jets is substantiated when establishing rational parameters of equipment for water

  16. Interactions between soil texture, water, and nutrients control patterns of biocrusts abundance and structure

    Science.gov (United States)

    Young, Kristina; Bowker, Matthew; Reed, Sasha; Howell, Armin

    2017-04-01

    Heterogeneity in the abiotic environment structures biotic communities by controlling niche space and parameters. This has been widely observed and demonstrated in vascular plant and other aboveground communities. While soil organisms are presumably also strongly influenced by the physical and chemical dimensions of the edaphic environment, there are fewer studies linking the development, structure, productivity or function of surface soil communities to specific edaphic gradients. Here, we use biological soil crusts (biocrusts) as a model system to determine mechanisms regulating community structure of soil organisms. We chose soil texture to serve as an edaphic gradient because of soil texture's influence over biocrust distribution on a landscape level. We experimentally manipulated texture in constructed soil, and simultaneously manipulated two main outcomes of texture, water and nutrient availability, to determine the mechanism underlying texture's influence on biocrust abundance and structure. We grew biocrust communities from a field-sourced inoculum on four different soil textures, sieved from the same parent soil material, manipulating watering levels and nutrient additions across soil textures in a full-factorial design over a 5-month period of time. We measured abundance and structure of biocrusts over time, and measured two metrics of function, N2 fixation rates and soil stabilization, at the conclusion of the experiment. Our results showed finer soil textures resulted in faster biocrust community development and dominance by mosses, whereas coarser textures grew more slowly and had biocrust communities dominated by cyanobacteria and lichen. Additionally, coarser textured soils contained cyanobacterial filaments significantly deeper into the soil profile than fine textured soils. N2-fixation values increased with increasing moss cover and decreased with increasing cyanobacterial cover, however, the rate of change depended on soil texture and water amount

  17. Roles of water in protein structure and function studied by molecular liquid theory.

    Science.gov (United States)

    Imai, Takashi

    2009-01-01

    The roles of water in the structure and function of proteins have not been completely elucidated. Although molecular simulation has been widely used for the investigation of protein structure and function, it is not always useful for elucidating the roles of water because the effect of water ranges from atomic to thermodynamic level. The three-dimensional reference interaction site model (3D-RISM) theory, which is a statistical-mechanical theory of molecular liquids, can yield the solvation structure at the atomic level and calculate the thermodynamic quantities from the intermolecular potentials. In the last few years, the author and coworkers have succeeded in applying the 3D-RISM theory to protein aqueous solution systems and demonstrated that the theory is useful for investigating the roles of water. This article reviews some of the recent applications and findings, which are concerned with molecular recognition by protein, protein folding, and the partial molar volume of protein which is related to the pressure effect on protein.

  18. Light Modulation and Water Splitting Enhancement Using a Composite Porous GaN Structure.

    Science.gov (United States)

    Yang, Chao; Xi, Xin; Yu, Zhiguo; Cao, Haicheng; Li, Jing; Lin, Shan; Ma, Zhanhong; Zhao, Lixia

    2018-02-14

    On the basis of the laterally porous GaN, we designed and fabricated a composite porous GaN structure with both well-ordered lateral and vertical holes. Compared to the plane GaN, the composite porous GaN structure with the combination of the vertical holes can help to reduce UV reflectance and increase the saturation photocurrent during water splitting by a factor of ∼4.5. Furthermore, we investigated the underlying mechanism for the enhancement of the water splitting performance using a finite-difference time-domain method. The results show that the well-ordered vertical holes can not only help to open the embedded pore channels to the electrolyte at both sides and reduce the migration distance of the gas bubbles during the water splitting reactions but also help to modulate the light field. Using this composite porous GaN structure, most of the incident light can be modulated and trapped into the nanoholes, and thus the electric fields localized in the lateral pores can increase dramatically as a result of the strong optical coupling. Our findings pave a new way to develop GaN photoelectrodes for highly efficient solar water splitting.

  19. Fabrication of superhydrophobic polyurethane/organoclay nano-structured composites from cyclomethicone-in-water emulsions

    International Nuclear Information System (INIS)

    Bayer, I.S.; Steele, A.; Martorana, P.J.; Loth, E.

    2010-01-01

    Nano-structured polyurethane/organoclay composite films were fabricated by dispersing moisture-curable polyurethanes and fatty amine/amino-silane surface modified montmorillonite clay (organoclay) in cyclomethicone-in-water emulsions. Cyclomethicone Pickering emulsions were made by emulsifying decamethylcyclopentasiloxane (D 5 ), dodecamethylcyclohexasiloxane (D 6 ) and aminofunctional siloxane polymers with water using montmorillonite particles as emulsion stabilizers. Polyurethane and organoclay dispersed emulsions were spray coated on aluminum surfaces. Upon thermosetting, water repellent self-cleaning coatings were obtained with measured static water contact angles exceeding 155 o and low contact angle hysteresis ( o ). Electron microscopy images of the coating surfaces revealed formation of self-similar hierarchical micro- and nano-scale surface structures. The surface morphology and the coating adhesion strength to aluminum substrates were found to be sensitive to the relative amounts of dispersed polyurethane and organoclay in the emulsions. The degree of superhydrophobicity was analyzed using static water contact angles as well as contact angle hysteresis measurements. Due to biocompatibility of cyclomethicones and polyurethane, developed coatings can be considered for specific bio-medical applications.

  20. Fabrication of superhydrophobic polyurethane/organoclay nano-structured composites from cyclomethicone-in-water emulsions

    Energy Technology Data Exchange (ETDEWEB)

    Bayer, I.S., E-mail: ibayer1@illinois.edu [Department of Aerospace Engineering, University of Illinois at Urbana-Champaign, IL 61801 (United States); Steele, A.; Martorana, P.J. [Department of Aerospace Engineering, University of Illinois at Urbana-Champaign, IL 61801 (United States); Loth, E. [Department of Aerospace Engineering, University of Illinois at Urbana-Champaign, IL 61801 (United States); Department of Mechanical and Aerospace Engineering, University of Virginia, VA 22904 (United States)

    2010-11-15

    Nano-structured polyurethane/organoclay composite films were fabricated by dispersing moisture-curable polyurethanes and fatty amine/amino-silane surface modified montmorillonite clay (organoclay) in cyclomethicone-in-water emulsions. Cyclomethicone Pickering emulsions were made by emulsifying decamethylcyclopentasiloxane (D{sub 5}), dodecamethylcyclohexasiloxane (D{sub 6}) and aminofunctional siloxane polymers with water using montmorillonite particles as emulsion stabilizers. Polyurethane and organoclay dispersed emulsions were spray coated on aluminum surfaces. Upon thermosetting, water repellent self-cleaning coatings were obtained with measured static water contact angles exceeding 155{sup o} and low contact angle hysteresis (<8{sup o}). Electron microscopy images of the coating surfaces revealed formation of self-similar hierarchical micro- and nano-scale surface structures. The surface morphology and the coating adhesion strength to aluminum substrates were found to be sensitive to the relative amounts of dispersed polyurethane and organoclay in the emulsions. The degree of superhydrophobicity was analyzed using static water contact angles as well as contact angle hysteresis measurements. Due to biocompatibility of cyclomethicones and polyurethane, developed coatings can be considered for specific bio-medical applications.

  1. Corrosion of structural materials and electrochemistry in high temperature water of nuclear power systems

    International Nuclear Information System (INIS)

    Uchida, Shunsuke

    2008-01-01

    The latest experiences with corrosion in the cooling systems of nuclear power plants are reviewed. High temperature cooling water causes corrosion of structural materials, which often leads to adverse effects in the plants, e.g., increased shutdown radiation, generation of defects in materials of major components and fuel claddings, and increased volume of radwaste sources. Corrosion behavior is greatly affected by water quality and differs according to the water quality values and the materials themselves. In order to establish reliable operation, each plant requires its own unique optimal water chemistry control based on careful consideration of its system, materials and operational history. Electrochemistry is one of the key issues that determine corrosion-related problems, but it is not the only issue. Most corrosion-related phenomena, e.g., flow accelerated corrosion (FAC), intergranular stress corrosion cracking (IGSCC), primary water stress corrosion cracking (PWSCC) and thinning of fuel cladding materials, can be understood based on an electrochemical index, e.g., the electrochemical corrosion potential (ECP), conductivities and pH. The most important electrochemical index, the ECP, can be measured at elevated temperature and applied to in situ sensors of corrosion conditions to detect anomalous conditions of structural materials at their very early stages. (orig.)

  2. Corrosion of structural materials and electrochemistry in high temperature water of nuclear power systems

    International Nuclear Information System (INIS)

    Uchida, Shunsuke

    2014-01-01

    The latest experiences with corrosion in the cooling systems of nuclear power plants are reviewed. High temperature cooling water causes corrosion of structural materials, which often leads to adverse effects in the plants, e.g., generating defects in materials of major components and fuel claddings, increasing shutdown radiation and increasing the volume of radwaste sources. Corrosion behaviors are much affected by water qualities and differ according to the values of water qualities and the materials themselves. In order to establish reliable operation, each plant requires its own unique optimal water chemistry control based on careful consideration of its system, materials and operational history. Electrochemistry is one of key issues that determine corrosion related problems but it is not the only issue. Most phenomena for corrosion related problems, e.g., flow-accelerated corrosion (FAC), intergranular stress corrosion cracking (IGSCC), primary water stress corrosion cracking (PWSCC) and thinning of fuel cladding materials, can be understood based on an electrochemical index, e.g., electrochemical corrosion potential (ECP), conductivities and pH. The most important electrochemical index, ECP, can be measured at elevated temperature and applied to in situ sensors of corrosion conditions to detect anomalous conditions of structural materials at their very early stages. In the paper, theoretical models based on electrochemistry to estimate wall thinning rate of carbon steel piping due to flow-accelerated corrosion and corrosive conditions determining IGSCC crack initiation and growth rate are introduced. (author)

  3. THE UTILIZATION STRUCTURE OF THERMAL WATER WELLS AND ITS UNEXPLOITED CAPACITIES IN HUNGARY

    Directory of Open Access Journals (Sweden)

    BALÁZS KULCSÁR

    2014-12-01

    Full Text Available In order to mitigate Hungary’s vulnerability in energy supply and accomplish the renewable energy production targets, it is essential to discover exploitable alternative opportunities for energy production and step up the utilization of the available capacities. The purpose of this publication is to map up the utilization structure of the existing Hungarian thermal water wells, describe its changes over the past 16 years, reveal the associated reasons and define the unutilized well capacities that may contribute to increasing the exploitation of geothermal heat by municipalities. The studies have been conducted in view of the Cadaster of Thermal Water Wells of Hungary compiled in 1994, the well cadasters kept by the regional water management directorates, as well as the data of the digital thermal water cadaster of 2010. The calculations performed for the evaluation of data have been based on the ratios and respective utilization areas of the existing wells. In the past 150 years, nearly 1500 thermal water wells have been drilled for use by a broad range of economic operations. The principal goals of constructing thermal water wells encompass the use of water in balneology, water and heat supply to the agriculture, hydrocarbon research and the satisfaction of municipal water demands. In 1994, 26% of the facilities was operated as baths, 21% was used by agriculture, while 13% and 12% served communal and waterworks supply, respectively. Then in 2010, 31% of thermal water wells was continued to be used for the water supply of bathing establishments, followed by 20% for agricultural use, 19% for utilization by waterworks, 11% for observation purposes and 10% for communal use. During the 16 years between 1994 and 2010, the priorities of utilization often changed, new demands emerged in addition to the former utilization goals of thermal water wells. The economic landscape and changes in consumer habits have transformed the group of consumers, which

  4. Probing ion-specific effects on aqueous acetate solutions: Ion pairing versus water structure modifications.

    Science.gov (United States)

    Petit, Tristan; Lange, Kathrin M; Conrad, Gerrit; Yamamoto, Kenji; Schwanke, Christoph; Hodeck, Kai F; Dantz, Marcus; Brandenburg, Tim; Suljoti, Edlira; Aziz, Emad F

    2014-05-01

    The effect of monovalent cations (Li(+), K(+), NH4 (+), Na(+)) on the water structure in aqueous chloride and acetate solutions was characterized by oxygen K-edge X-ray absorption spectroscopy (XAS), X-ray emission spectroscopy, and resonant inelastic X-ray scattering (RIXS) of a liquid microjet. We show ion- and counterion dependent effects on the emission spectra of the oxygen K-edge, which we attribute to modifications of the hydrogen bond network of water. For acetates, ion pairing with carboxylates was also probed selectively by XAS and RIXS. We correlate our experimental results to speciation data and to the salting-out properties of the cations.

  5. Structures, Energetics and Spectroscopic Fingerprints of Water Clusters n=2-24

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Soohaeng; Xantheas, Sotiris S.

    2017-06-08

    This chapter discusses the structures, energetics, and vibrational spectra of the first few (n$24) water clusters obtained from high-level electronic structure calculations. The results are discussed in the perspective of being used to parameterize/assess the accuracy of classical and quantum force fields for water. To this end, a general introduction with the classification of those force fields is presented. Several low-lying families of minima for the medium cluster sizes are considered. The transition from the “all surface” to the “fully coordinated” cluster structures occurring at nD17 and its spectroscopic signature is presented. The various families of minima for nD20 are discussed together with the low energy networks of the pentagonal dodecahedron (H2O)20 water cage. Finally, the low-energy networks of the tetrakaidecahedron (T-cage) (H2O)24 cluster are shown and their significance in the construction of periodic lattices of structure I (sI) of the hydrate lattices is discussed.

  6. Water footprint of crop production for different crop structures in the Hebei southern plain, North China

    Science.gov (United States)

    Chu, Yingmin; Shen, Yanjun; Yuan, Zaijian

    2017-06-01

    The North China Plain (NCP) has a serious shortage of freshwater resources, and crop production consumes approximately 75 % of the region's water. To estimate water consumption of different crops and crop structures in the NCP, the Hebei southern plain (HSP) was selected as a study area, as it is a typical region of groundwater overdraft in the NCP. In this study, the water footprint (WF) of crop production, comprised of green, blue and grey water footprints, and its annual variation were analyzed. The results demonstrated the following: (1) the WF from the production of main crops was 41.8 km3 in 2012. Winter wheat, summer maize and vegetables were the top water-consuming crops in the HSP. The water footprint intensity (WFI) of cotton was the largest, and for vegetables, it was the smallest; (2) the total WF, WFblue, WFgreen and WFgrey for 13 years (2000-2012) of crop production were 604.8, 288.5, 141.3 and 175.0 km3, respectively, with an annual downtrend from 2000 to 2012; (3) winter wheat, summer maize and vegetables consumed the most groundwater, and their blue water footprint (WFblue) accounted for 74.2 % of the total WFblue in the HSP; (4) the crop structure scenarios analysis indicated that, with approximately 20 % of arable land cultivated with winter wheat-summer maize in rotation, 38.99 % spring maize, 10 % vegetables and 10 % fruiters, a sustainable utilization of groundwater resources can be promoted, and a sufficient supply of food, including vegetables and fruits, can be ensured in the HSP.

  7. Water footprint of crop production for different crop structures in the Hebei southern plain, North China

    Directory of Open Access Journals (Sweden)

    Y. Chu

    2017-06-01

    Full Text Available The North China Plain (NCP has a serious shortage of freshwater resources, and crop production consumes approximately 75 % of the region's water. To estimate water consumption of different crops and crop structures in the NCP, the Hebei southern plain (HSP was selected as a study area, as it is a typical region of groundwater overdraft in the NCP. In this study, the water footprint (WF of crop production, comprised of green, blue and grey water footprints, and its annual variation were analyzed. The results demonstrated the following: (1 the WF from the production of main crops was 41.8 km3 in 2012. Winter wheat, summer maize and vegetables were the top water-consuming crops in the HSP. The water footprint intensity (WFI of cotton was the largest, and for vegetables, it was the smallest; (2 the total WF, WFblue, WFgreen and WFgrey for 13 years (2000–2012 of crop production were 604.8, 288.5, 141.3 and 175.0 km3, respectively, with an annual downtrend from 2000 to 2012; (3 winter wheat, summer maize and vegetables consumed the most groundwater, and their blue water footprint (WFblue accounted for 74.2 % of the total WFblue in the HSP; (4 the crop structure scenarios analysis indicated that, with approximately 20 % of arable land cultivated with winter wheat–summer maize in rotation, 38.99 % spring maize, 10 % vegetables and 10 % fruiters, a sustainable utilization of groundwater resources can be promoted, and a sufficient supply of food, including vegetables and fruits, can be ensured in the HSP.

  8. Structure and dynamics of the peptide strand KRFK from the thrombospondin TSP-1 in water.

    Science.gov (United States)

    Taleb Bendiab, W; Benomrane, B; Bounaceur, B; Dauchez, M; Krallafa, A M

    2018-02-14

    Theoretical investigations of a solute in liquid water at normal temperature and pressure can be performed at different levels of theory. Static quantum calculations as well as classical and ab initio molecular dynamics are used to completely explore the conformational space for large solvated molecular systems. In the classical approach, it is essential to describe all of the interactions of the solute and the solvent in detail. Water molecules are very often described as rigid bodies when the most commonly used interaction potentials, such as the SPCE and the TIP4P models, are employed. Recently, a physical model based upon a cluster of rigid water molecules with a tetrahedral architecture (AB 4 ) was proposed that describes liquid water as a mixture of both TIP4P and SPCE molecular species that occur in the proportions implied by the tetrahedral architecture (one central molecule versus four outer molecules; i.e., 20% TIP4P versus 80% SPCE molecules). In this work, theoretical spectroscopic data for a peptide strand were correlated with the structural properties of the peptide strand solvated in water, based on data calculated using different theoretical approaches and physical models. We focused on a particular peptide strand, KRFK (lysine-arginine-phenylalanine-lysine), found in the thrombospondin TSP-1, due to its interesting properties. As the activity and electronic structure of this system is strongly linked to its structure, we correlated its structure with charge-density maps obtained using different semi-empirical charge Q eq equations. The structural and thermodynamic properties obtained from classical simulations were correlated with ab initio molecular dynamics (AIMD) data. Structural changes in the peptide strand were rationalized in terms of the motions of atoms and groups of atoms. To achieve this, conformational changes were investigated using calculated infrared spectra for the peptide in the gas phase and in water solvent. The calculated AIMD

  9. The structural modification of cassava starch using a saline water pretreatment

    Directory of Open Access Journals (Sweden)

    Hanny Frans SANGIAN

    2018-04-01

    Full Text Available Abstract The cassava has been modified successfully by using the saline water, which was abundantly available on the planet. The biomass was submerged in saline waters that salt concentrations were altered at 0, 3.5 percent (seawater and 10 percent (w/w and were kept 5 days. After recovery by washing steps, the treated solids were characterized by using XRD (X-ray diffraction , FTIR (Fourier transform infra-red, and SEM (Scanning electron microscopic. The results showed that the XRD pattern of saline water pretreatment decreased significantly. The biggest decrease of X-ray intensity occurred at around 18o. Meanwhile, the fingerprint of FTIR revealed the transmittance intensity of infra-red ray of saline water treated solid inclined for all wave constant numbers, suggesting that many hydrogen bonds were disconnected. Those findings also were enhanced by SEM pictures that showed the change of surface morphology of treated biomass. It was indicative that cassava structure was modified becoming more textured after employing saline water pretreatment. This work is an innovative finding to gradually substitute commercial ionic liquids that are very expensive with saline water for biomass pretreatment.

  10. Water and the Interior Structure of Terrestrial Planets and Icy Bodies

    Science.gov (United States)

    Monteux, J.; Golabek, G. J.; Rubie, D. C.; Tobie, G.; Young, E. D.

    2018-02-01

    Water content and the internal evolution of terrestrial planets and icy bodies are closely linked. The distribution of water in planetary systems is controlled by the temperature structure in the protoplanetary disk and dynamics and migration of planetesimals and planetary embryos. This results in the formation of planetesimals and planetary embryos with a great variety of compositions, water contents and degrees of oxidation. The internal evolution and especially the formation time of planetesimals relative to the timescale of radiogenic heating by short-lived 26Al decay may govern the amount of hydrous silicates and leftover rock-ice mixtures available in the late stages of their evolution. In turn, water content may affect the early internal evolution of the planetesimals and in particular metal-silicate separation processes. Moreover, water content may contribute to an increase of oxygen fugacity and thus affect the concentrations of siderophile elements within the silicate reservoirs of Solar System objects. Finally, the water content strongly influences the differentiation rate of the icy moons, controls their internal evolution and governs the alteration processes occurring in their deep interiors.

  11. Transcription arrest by a G quadruplex forming-trinucleotide repeat sequence from the human c-myb gene.

    Science.gov (United States)

    Broxson, Christopher; Beckett, Joshua; Tornaletti, Silvia

    2011-05-17

    Non canonical DNA structures correspond to genomic regions particularly susceptible to genetic instability. The transcription process facilitates formation of these structures and plays a major role in generating the instability associated with these genomic sites. However, little is known about how non canonical structures are processed when encountered by an elongating RNA polymerase. Here we have studied the behavior of T7 RNA polymerase (T7RNAP) when encountering a G quadruplex forming-(GGA)(4) repeat located in the human c-myb proto-oncogene. To make direct correlations between formation of the structure and effects on transcription, we have taken advantage of the ability of the T7 polymerase to transcribe single-stranded substrates and of G4 DNA to form in single-stranded G-rich sequences in the presence of potassium ions. Under physiological KCl concentrations, we found that T7 RNAP transcription was arrested at two sites that mapped to the c-myb (GGA)(4) repeat sequence. The extent of arrest did not change with time, indicating that the c-myb repeat represented an absolute block and not a transient pause to T7 RNAP. Consistent with G4 DNA formation, arrest was not observed in the absence of KCl or in the presence of LiCl. Furthermore, mutations in the c-myb (GGA)(4) repeat, expected to prevent transition to G4, also eliminated the transcription block. We show T7 RNAP arrest at the c-myb repeat in double-stranded DNA under conditions mimicking the cellular concentration of biomolecules and potassium ions, suggesting that the G4 structure formed in the c-myb repeat may represent a transcription roadblock in vivo. Our results support a mechanism of transcription-coupled DNA repair initiated by arrest of transcription at G4 structures.

  12. Atomistic structure of cobalt-phosphate nanoparticles for catalytic water oxidation.

    Science.gov (United States)

    Hu, Xiao Liang; Piccinin, Simone; Laio, Alessandro; Fabris, Stefano

    2012-12-21

    Solar-driven water splitting is a key photochemical reaction that underpins the feasible and sustainable production of solar fuels. An amorphous cobalt-phosphate catalyst (Co-Pi) based on earth-abundant elements has been recently reported to efficiently promote water oxidation to protons and dioxygen, a main bottleneck for the overall process. The structure of this material remains largely unknown. We here exploit ab initio and classical atomistic simulations combined with metadynamics to build a realistic and statistically meaningful model of Co-Pi nanoparticles. We demonstrate the emergence and stability of molecular-size ordered crystallites in nanoparticles initially formed by a disordered Co-O network and phosphate groups. The stable crystallites consist of bis-oxo-bridged Co centers that assemble into layered structures (edge-sharing CoO(6) octahedra) as well as in corner- and face-sharing cubane units. These layered and cubane motifs coexist in the crystallites, which always incorporate disordered phosphate groups at the edges. Our computational nanoparticles, although limited in size to ~1 nm, can contain more than one crystallite and incorporate up to 18 Co centers in the cubane/layered structures. The crystallites are structurally stable up to high temperatures. We simulate the extended X-ray absorption fine structure (EXAFS) of our nanoparticles. Those containing several complete and incomplete cubane motifs-which are believed to be essential for the catalytic activity-display a very good agreement with the experimental EXAFS spectra of Co-Pi grains. We propose that the crystallites in our nanoparticles are reliable structural models of the Co-Pi catalyst surface. They will be useful to reveal the origin of the catalytic efficiency of these novel water-oxidation catalysts.

  13. Identifying non-technical skills and barriers for improvement of teamwork in cardiac arrest teams

    DEFF Research Database (Denmark)

    Andersen, P.O.; Jensen, Michael Kammer; Lippert, A.

    2010-01-01

    Background: The application of non-technical skills (NTSs) in health care has previously been described in other health-care educational programmes. NTSs are behavioural principles such as leadership, task distribution and communication. The aim of this study was to identify NTSs suitable...... for improving team performance in multi-professional cardiac arrest teams, and to describe barriers to the use and implementation of such NTSs by using a qualitative method. Methods: Individual semi-structured interviews were conducted with 11 Danish Advanced Life Support instructors during the period April...... 2006 to November 2006. Interviews were focussed on barriers and recommendations for teamwork in the cardiac arrest team, optimal policy for improvement of resuscitation training and clinical practice, use of cognitive aids and adoption of European Resuscitation Council (ERC) Guidelines 2005. Interviews...

  14. Variance in water chemistry parameters in isolated wetlands of Florida, USA, and relationships with macroinvertebrate and diatom community structure

    Science.gov (United States)

    Eighty small isolated wetlands throughout Florida were sampled in 2005 to explore within-site variability of water chemistry parameters and relate water chemistry to macroinvertebrate and diatom community structure. Three samples or measures of water were collected within each si...

  15. Moisture harvesting and water transport through specialized micro-structures on the integument of lizards.

    Science.gov (United States)

    Comanns, Philipp; Effertz, Christian; Hischen, Florian; Staudt, Konrad; Böhme, Wolfgang; Baumgartner, Werner

    2011-01-01

    Several lizard species that live in arid areas have developed special abilities to collect water with their bodies' surfaces and to ingest the so collected moisture. This is called rain- or moisture-harvesting. The water can originate from air humidity, fog, dew, rain or even from humid soil. The integument (i.e., the skin plus skin derivatives such as scales) has developed features so that the water spreads and is soaked into a capillary system in between the reptiles' scales. Within this capillary system the water is transported to the mouth where it is ingested. We have investigated three different lizard species which have developed the ability for moisture harvesting independently, viz. the Australian thorny devil (Moloch horridus), the Arabian toadhead agama (Phrynocephalus arabicus) and the Texas horned lizard (Phrynosoma cornutum). All three lizards have a honeycomb like micro ornamentation on the outer surface of the scales and a complex capillary system in between the scales. By investigation of individual scales and by producing and characterising polymer replicas of the reptiles' integuments, we found that the honeycomb like structures render the surface superhydrophilic, most likely by holding a water film physically stable. Furthermore, the condensation of air humidity is improved on this surface by about 100% in comparison to unstructured surfaces. This allows the animals to collect moisture with their entire body surface. The collected water is transported into the capillary system. For Phrynosoma cornutum we found the interesting effect that, in contrast to the other two investigated species, the water flow in the capillary system is not uniform but directed to the mouth. Taken together we found that the micro ornamentation yields a superhydrophilic surface, and the semi-tubular capillaries allow for an efficient passive - and for Phrynosoma directed - transport of water.

  16. Moisture harvesting and water transport through specialized micro-structures on the integument of lizards

    Directory of Open Access Journals (Sweden)

    Philipp Comanns

    2011-04-01

    Full Text Available Several lizard species that live in arid areas have developed special abilities to collect water with their bodies' surfaces and to ingest the so collected moisture. This is called rain- or moisture-harvesting. The water can originate from air humidity, fog, dew, rain or even from humid soil. The integument (i.e., the skin plus skin derivatives such as scales has developed features so that the water spreads and is soaked into a capillary system in between the reptiles' scales. Within this capillary system the water is transported to the mouth where it is ingested. We have investigated three different lizard species which have developed the ability for moisture harvesting independently, viz. the Australian thorny devil (Moloch horridus, the Arabian toadhead agama (Phrynocephalus arabicus and the Texas horned lizard (Phrynosoma cornutum. All three lizards have a honeycomb like micro ornamentation on the outer surface of the scales and a complex capillary system in between the scales. By investigation of individual scales and by producing and characterising polymer replicas of the reptiles' integuments, we found that the honeycomb like structures render the surface superhydrophilic, most likely by holding a water film physically stable. Furthermore, the condensation of air humidity is improved on this surface by about 100% in comparison to unstructured surfaces. This allows the animals to collect moisture with their entire body surface. The collected water is transported into the capillary system. For Phrynosoma cornutum we found the interesting effect that, in contrast to the other two investigated species, the water flow in the capillary system is not uniform but directed to the mouth. Taken together we found that the micro ornamentation yields a superhydrophilic surface, and the semi-tubular capillaries allow for an efficient passive – and for Phrynosoma directed – transport of water.

  17. Moisture harvesting and water transport through specialized micro-structures on the integument of lizards

    Science.gov (United States)

    Comanns, Philipp; Effertz, Christian; Hischen, Florian; Staudt, Konrad; Böhme, Wolfgang

    2011-01-01

    Summary Several lizard species that live in arid areas have developed special abilities to collect water with their bodies' surfaces and to ingest the so collected moisture. This is called rain- or moisture-harvesting. The water can originate from air humidity, fog, dew, rain or even from humid soil. The integument (i.e., the skin plus skin derivatives such as scales) has developed features so that the water spreads and is soaked into a capillary system in between the reptiles' scales. Within this capillary system the water is transported to the mouth where it is ingested. We have investigated three different lizard species which have developed the ability for moisture harvesting independently, viz. the Australian thorny devil (Moloch horridus), the Arabian toadhead agama (Phrynocephalus arabicus) and the Texas horned lizard (Phrynosoma cornutum). All three lizards have a honeycomb like micro ornamentation on the outer surface of the scales and a complex capillary system in between the scales. By investigation of individual scales and by producing and characterising polymer replicas of the reptiles' integuments, we found that the honeycomb like structures render the surface superhydrophilic, most likely by holding a water film physically stable. Furthermore, the condensation of air humidity is improved on this surface by about 100% in comparison to unstructured surfaces. This allows the animals to collect moisture with their entire body surface. The collected water is transported into the capillary system. For Phrynosoma cornutum we found the interesting effect that, in contrast to the other two investigated species, the water flow in the capillary system is not uniform but directed to the mouth. Taken together we found that the micro ornamentation yields a superhydrophilic surface, and the semi-tubular capillaries allow for an efficient passive – and for Phrynosoma directed – transport of water. PMID:21977432

  18. Effects of clustering structure on volumetric properties of amino acids in (DMSO + water) mixtures

    International Nuclear Information System (INIS)

    Huang Aimin; Liu Chunli; Ma Lin; Tong Zhangfa; Lin Ruisen

    2012-01-01

    Graphical abstract: Together with static light scattering measurement, volumetric properties of glycine, L-alanine and L-serine were determined and utilized to reveal the microscopic solvent structure of (DMSO + water) mixtures and its influence on the interaction between DMSO and amino acids from a clustering point of view. The results demonstrated that the interaction between amino acids and DMSO was greatly related to the clustering structure of the mixed solvent and that amino acids interacted with already established solvent clusters. Hydrophobic aggregating of DMSO lead to a decrease in the hydrophobic effect of DMSO and the hydrophobic–hydrophilic and hydrophobic–hydrophobic interaction with amino acids, which was reflected by the solvation of proteins. Highlights: ► Determine volumetric properties of three amino acids in aqueous DMSO in details. ► Static light scattering measurement for clustering structure of aqueous DMSO. ► Volumetric behaviour of amino acids depends on clustering structure of aqueous DMSO. ► Clustering structure of aqueous DMSO influences solvation of protein and cellulose. - Abstract: For a better understanding on the functions of DMSO in biological systems at a relatively lower concentration, apparent molar volumes of three typical amino acids, glycine, L-alanine and L-serine in (DMSO + water) mixtures were determined and the transfer volumes from water to the mixtures were evaluated. Together with static light scattering measurement, the results were utilised to reveal the microscopic solvent structure of (DMSO + water) mixtures and its influence on the interaction between DMSO and amino acids from a clustering point of view. The results demonstrate that the interaction between amino acids and DMSO is greatly related to the clustering structure of the mixed solvent and that amino acids interacted with already established solvent clusters. The linear dependence of transfer volume of amino acids on DMSO concentration up to 2

  19. Probing the electronic structure of liquid water with many-body perturbation theory

    Science.gov (United States)

    Pham, Tuan Anh; Zhang, Cui; Schwegler, Eric; Galli, Giulia

    2014-03-01

    We present a first-principles investigation of the electronic structure of liquid water based on many-body perturbation theory (MBPT), within the G0W0 approximation. The liquid quasiparticle band gap and the position of its valence band maximum and conduction band minimum with respect to vacuum were computed and it is shown that the use of MBPT is crucial to obtain results that are in good agreement with experiment. We found that the level of theory chosen to generate molecular dynamics trajectories may substantially affect the electronic structure of the liquid, in particular, the relative position of its band edges and redox potentials. Our results represent an essential step in establishing a predictive framework for computing the relative position of water redox potentials and the band edges of semiconductors and insulators. Work supported by DOE/BES (Grant No. DE-SC0008938). Work at LLNL was performed under Contract DE-AC52-07NA27344.

  20. Effect of biochar on soil structural characteristics: water retention and gas transport

    DEFF Research Database (Denmark)

    Sun, Zhencai; Møldrup, Per; Vendelboe, Anders Lindblad

    Biochar addition to agricultural soil has been reported to reduce climate gas emission, as well as improve soil fertility and crop productivity. Little, however, is known about biochar effects on soil structural characteristics. This study investigates if biochar-application changes soil structural...... characteristics, as indicated from water retention and gas transport measurements on intact soil samples. Soil was sampled from a field experiment on a sandy loam with four control plots (C) without biochar and four plots (B) with incorporated biochar at a rate of 20 tons per hectare (plot size, 6 x 8 m). The C......-gas diffusivity on intact 100cm3 soil samples (5 replicates in each plot). We found that biochar application significantly decreased soil bulk density, hereby creating higher porosity. At the same soil-water matric potential, all the soil-gas phase parameters (air-filled porosity, air permeability and gas...

  1. Water vapor weathering of Taurus-Littrow orange soil - A pore-structure analysis

    Science.gov (United States)

    Cadenhead, D. A.; Mikhail, R. S.

    1975-01-01

    A pore-volume analysis was performed on water vapor adsorption data previously obtained on a fresh sample of Taurus-Littrow orange soil, and the analysis was repeated on the same sample after its exposure to moist air for a period of approximately six months. The results indicate that exposure of an outgassed sample to high relative pressures of water vapor can result in the formation of substantial micropore structure, the precise amount being dependent on the sample pretreatment, particularly the outgassing temperature. Micropore formation is explained in terms of water penetration into surface defects. In contrast, long-term exposure to moist air at low relative pressures appears to reverse the process with the elimination of micropores and enlargement of mesopores possibly through surface diffusion of metastable adsorbent material. The results are considered with reference to the storage of lunar samples.

  2. Structure and dynamics of water and lipid molecules in charged anionic DMPG lipid bilayer membranes

    DEFF Research Database (Denmark)

    Rønnest, A. K.; Peters, Günther H.J.; Hansen, Flemming Yssing

    2016-01-01

    Molecular dynamics simulations have been used to investigate the influence of the valency of counter-ions on the structure of freestanding bilayer membranes of the anionic 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) lipid at 310 K and 1 atm. At this temperature, the membrane is in the fluid...... compared to experimental results and used to determine an average diffusion constant for all water molecules in the system. On extrapolating the diffusion constants inferred experimentally to a temperature of 310 K, reasonable agreement with the simulations is obtained. However, the experiments do not have...... the sensitivity to confirm the diffusion of a small component of water bound to the lipids as found in the simulations. In addition, the orientation of the dipole moment of the water molecules has been determined as a function of their depth in the membrane. Previous indirect estimates of the electrostatic...

  3. Analysis of water hammer-structure interaction in piping system for a loss of coolant accident in primary loop of pressurized water reactor

    International Nuclear Information System (INIS)

    Zhang Xiwen; Yang Jinglong; He Feng; Wang Xuefang

    2000-01-01

    The conventional analysis of water hammer and dynamics response of structure in piping system is divided into two parts, and the interaction between them is neglected. The mechanism of fluid-structure interaction under the double-end break pipe in piping system is analyzed. Using the characteristics method, the numerical simulation of water hammer-structure interaction in piping system is completed based on 14 parameters and 14 partial differential equations of fluid-piping cell. The calculated results for a loss of coolant accident (LOCA) in primary loop of pressurized water reactor show that the waveform and values of pressure and force with time in piping system are different from that of non-interaction between water hammer and structure in piping system, and the former is less than the later

  4. Mixing of alcohol and water molecules studied by neutron probe. Structure and dynamics

    International Nuclear Information System (INIS)

    Yoshida, Koji

    2001-01-01

    Structure of water/alcohol mixing solution was studied by three methods such as an isotope-exchanged neutron scattering method, RISM (Reference Interaction Site Model) integral equation and a neutron spin echo method. The principle of methods, experiments and results were reported. The results of experiments of water/tert-butyl alcohol (TBA) solution by the isotope-exchange neutron scattering method showed TBA molecule associated with each other through end methyl group. Especially this effect was the largest at x TBA = 0.06 and decreased with increasing the concentration of TBA. However, hydrogen bonding of TBA was very rare at x TBA = 0.06. By the partial radial distribution function obtained from RISM integral equation, it indicated that the structure of pure TBA became chain structure by hydrogen bond but changed to the structure contacted directly each hydrophobic group with increasing the concentration of water. Water/2-butoxyethanol (BE) mixing solution was measured by a neutron spin echo method. The activation energy of the diffusion coefficients obtained agreed to the energy of hydrogen bonding. The temperature response of diffusion coefficients showed the inverse of the experimental results obtained by the dynamic light scattering method. The difference between two measurement methods was different time scale and space scale. Namely, the object of the neutron scattering method is nano meter and nano second, but one of light scattering method many times over. It was proved from the above results that there was the cluster consisted of the same kind of molecule in the homogeneous two components solution, but the cluster was not stable and constantly exchanged with molecule, where the production and decay of the cluster is repeated at about nano sec. (S.Y.)

  5. Data needs for the track structure of alpha particles and electrons in water

    International Nuclear Information System (INIS)

    Pagnamenta, A.

    1983-01-01

    We have made calculations of the ionization spectra for alpha particle and electron tracks in water. We have also computed the number of ions created per micrometre of track length, the energy distribution of the secondaries, and the energy expended per ion pair created. Our aim is less toward theoretical derivations than to obtain a numerically accurate description of the track structure at all energies in a form suitable for biomedical applications. 13 references

  6. Heavy water effects on the structure, functions and behavior of biological systems

    International Nuclear Information System (INIS)

    Buzgariu, Wanda; Caloianu, Maria; Moldovan, Lucia; Titescu, G.

    2003-01-01

    The H 2 O substitution for D 2 O either in environment or in the culture medium of the living systems generates changes in their main functions and composition. In this paper some of the heavy water effects in biological systems such as structural and functional changes were reviewed: normal cell architecture alterations, cell division and membrane functions disturbance, muscular contractility and the perturbations of biological oscillators such as circadian rhythm, heart rate, respiratory cycle, tidal and ultradian rhythm. (authors)

  7. Physiology and microbial community structure in soil at extreme water content

    Czech Academy of Sciences Publication Activity Database

    Uhlířová, Eva; Elhottová, Dana; Tříska, Jan; Šantrůčková, Hana

    2005-01-01

    Roč. 50, č. 2 (2005), s. 161-166 ISSN 0015-5632 R&D Projects: GA ČR(CZ) GA206/99/1410; GA ČR(CZ) GA526/99/P033 Institutional research plan: CEZ:AV0Z6066911 Keywords : microbial community structure * soils * extreme water content Subject RIV: EH - Ecology, Behaviour Impact factor: 0.918, year: 2005

  8. Yield of reversible colloidal gels during flow start-up: release from kinetic arrest.

    Science.gov (United States)

    Johnson, Lilian C; Landrum, Benjamin J; Zia, Roseanna N

    2018-06-05

    Yield of colloidal gels during start-up of shear flow is characterized by an overshoot in shear stress that accompanies changes in network structure. Prior studies of yield of reversible colloidal gels undergoing strong flow model the overshoot as the point at which network rupture permits fluidization. However, yield under weak flow, which is of interest in many biological and industrial fluids shows no such disintegration. The mechanics of reversible gels are influenced by bond strength and durability, where ongoing rupture and re-formation impart aging that deepens kinetic arrest [Zia et al., J. Rheol., 2014, 58, 1121], suggesting that yield be viewed as release from kinetic arrest. To explore this idea, we study reversible colloidal gels during start-up of shear flow via dynamic simulation, connecting rheological yield to detailed measurements of structure, bond dynamics, and potential energy. We find that pre-yield stress grows temporally with the changing roles of microscopic transport processes: early time behavior is set by Brownian diffusion; later, advective displacements permit relative particle motion that stretches bonds and stores energy. Stress accumulates in stretched, oriented bonds until yield, which is a tipping point to energy release, and is passed with a fully intact network, where the loss of very few bonds enables relaxation of many, easing glassy arrest. This is immediately followed by a reversal to growth in potential energy during bulk plastic deformation and condensation into larger particle domains, supporting the view that yield is an activated release from kinetic arrest. The continued condensation of dense domains and shrinkage of network surfaces, along with a decrease in the potential energy, permit the gel to evolve toward more complete phase separation, supporting our view that yield of weakly sheared gels is a 'non-equilibrium phase transition'. Our findings may be particularly useful for industrial or other coatings, where weak

  9. Design and analysis of the DII-D radiative divertor water-cooled structures

    International Nuclear Information System (INIS)

    Hollerbach, M.A.; Smith, J.P.; Baxi, C.B.; Bozek; Chin, E.; Phelps, R.D.; Redler, K.M.; Reis, E.E.

    1995-10-01

    The Radiative Divertor is a major modification to the divertor of DIII-D and is being designed and fabricated for installation in late 1996. The Radiative Divertor Program (RDP) will enhance the dissipative processes in the edge and divertor plasmas to reduce the heat flux and plasma erosion at the divertor target. This approach will have major implications for the heat removal methods used in future devices. The divertor is of slot-type configuration designed to minimize the flow of sputtered and injected impurities back to the core plasma. The new divertor will be composed of toroidally continuous, Inconel 625 water-cooled rings of sandwich construction with an internal water channel, incorporating seam welding to provide the water-to-vacuum seal as well as structural integrity. The divertor structure is designed to withstand electromagnetic loads as a result of halo currents and induced toroidal currents. It also accommodates the thermal differences experienced during the 400 degrees C bake used on DIII-D. A low Z plasma-facing surface is provided by mechanically attached graphite tiles. Water flow through the rings will inertially cool these tiles which will be subjected to 38 MW, 10 second pulses. Current schedules call for detailed design in 1996 with installation completed in March 1997. A full size prototype, one-quarter of one ring, is being built to validate manufacturing techniques, machining, roll-forming, and seam welding. The experience and knowledge gained through the fabrication of the prototype is discussed. The design of the electrically isolated (5 kV) vacuum-to-air water feedthroughs supplying the water-cooled rings is also discussed

  10. Design and analysis of the DIII-D radiative divertor water-cooled structures

    International Nuclear Information System (INIS)

    Hollerbach, M.A.; Smith, J.P.; Baxi, C.B.; Bozek, A.S.; Chin, E.; Phelps, R.D.; Redler, K.M.; Reis, E.E.

    1995-01-01

    The Radiative Divertor is a major modification to the divertor of DIII-D and is being designed and fabricated for installation in late 1996. The Radiative Divertor Program (RDP) will enhance the dissipative processes in the edge and divertor plasmas to reduce the heat flux and plasma erosion at the divertor target. This approach will have major implications for the heat removal methods used in future devices. The divertor is of slot-type configuration designed to minimize the flow of sputtered and injected impurities back to the core plasma. The new divertor will be composed of toroidally continuous, Inconel 625 water-cooled rings of sandwich construction with an internal water channel, incorporating seam welding to provide the water-to-vacuum seal as well as structural integrity. The divertor structure is designed to withstand electro-magnetic loads as a result of halo currents and induced toroidal currents. It also accommodates the thermal differences experienced during the 400 C bake used on DIII-D. A low Z plasma-facing surface is provided by mechanically attached graphite tiles. Water flow through the rings will inertially cool these tiles which will be subjected to 38 MW, 10 second pulses. Current schedules call for detailed design in 1996 with installation completed in March 1997. A full size prototype, one-quarter of one ring, is being built to validate manufacturing techniques, machining, roll-forming, and seam welding. The experience and knowledge gained through the fabrication of the prototype is discussed. The design of the electrically isolated (5 kV) vacuum-to-air water feedthroughs supplying the water-cooled rings is also discussed

  11. Molecular simulation of the water-triolein-oleic acid mixture: Local structure and thermodynamic properties

    Science.gov (United States)

    Couallier, E.; Riaublanc, A.; David Briand, E.; Rousseau, B.

    2018-05-01

    An artificial oil-in-water emulsion analogous to those found in bioresources or food matrices is simulated and studied experimentally. It is composed of one of the major natural free fatty acids (the oleic acid, OA) and the corresponding triacylglyceride (trioleic glyceride, or triolein, GTO). Because of the large time and length scales involved, the molecular simulations are done with the Martini force field, a coarse-grained model. This allowed us to study the water-OA-GTO system at different compositions with more than 20 000 molecules and up to 2 μs. Interfacial tension was measured using the pendant drop method and compared with molecular simulation results. We observe very good agreement at high OA concentrations and deviations up to 15% at low OA concentrations. The water solubility in the lipid phase is in fair agreement with experiments, between 0.03 and 0.32 mol/l, rising with the OA content. The area occupied by OA and GTO at the interface between water and the pure product fitted with experimental data (AOA = 36.6 Å2 and AGTO = 152.1 Å2). The consistency between simulation and experimental results allowed a structural analysis of the interface. A bilayer structure of the lipids at the water/oil interface is proposed, containing preferentially oleic acid but also triolein. Through all these results, the usefulness of coarse-grained simulation for the description of water-oil interfacial organization is demonstrated. This method will be used later to bring local information on the organization of target compounds, necessary in biomass fractionation processes or food additive formulations, for example.

  12. Prediction of cardiac arrest recurrence using ensemble classifiers

    Indian Academy of Sciences (India)

    Nachiket Tapas

    ECG dataset from PhysioNet, Pima Indian Diabetes dataset from UCI Machine Learning Repository and gene expression ... electrical activity, medically the condition is known as cardiac arrest ... ing, (5) lack of physical exercise, etc. [9]. Using ...

  13. Arrest of cytoplasmic streaming induces algal proliferation in green paramecia.

    Directory of Open Access Journals (Sweden)

    Toshiyuki Takahashi

    Full Text Available A green ciliate Paramecium bursaria, bearing several hundreds of endosymbiotic algae, demonstrates rotational microtubule-based cytoplasmic streaming, in which cytoplasmic granules and endosymbiotic algae flow in a constant direction. However, its physiological significance is still unknown. We investigated physiological roles of cytoplasmic streaming in P. bursaria through host cell cycle using video-microscopy. Here, we found that cytoplasmic streaming was arrested in dividing green paramecia and the endosymbiotic algae proliferated only during the arrest of cytoplasmic streaming. Interestingly, arrest of cytoplasmic streaming with pressure or a microtubule drug also induced proliferation of endosymbiotic algae independently of host cell cycle. Thus, cytoplasmic streaming may control the algal proliferation in P. bursaria. Furthermore, confocal microscopic observation revealed that a division septum was formed in the constricted area of a dividing paramecium, producing arrest of cytoplasmic streaming. This is a first report to suggest that cytoplasmic streaming controls proliferation of eukaryotic cells.

  14. The outcome of anaesthesia related cardiac arrest in a

    Directory of Open Access Journals (Sweden)

    O.O. Adekola

    2016-07-01

    Conclusion: Anaesthesia related cardiac arrest and mortality were linked to cardiovascular depression from halothane overdose in our institution. The burden can be reduced by improving on establishing standard monitoring in the perioperative period, and a team approach to patients care.

  15. Attenuation and Velocity Structure in Spain and Morocco: Distinguishing Between Water, Temperature, and Partial Melt

    Science.gov (United States)

    Bezada, M. J.; Humphreys, E.

    2014-12-01

    Temperature, melt fraction, and water content affect seismic velocity and attenuation differently. Both are sensitive to temperature, but velocity is more sensitive to melt fraction and attenuation is thought to be more sensitive to water content. For these reasons, combining attenuation measurements with tomographic imaging of velocity structure can help untangle these fields and better resolve lithospheric structure and physical state. We map variations in attenuation beneath Spain and northern Morocco using teleseismic data generated by more than a dozen teleseismic deep-focus earthquakes recorded on a dense array of stations. For each event, we first estimate the source from the best quality recordings. We then apply an attenuation operator to the source estimate, using a range of t* values, to match the record at each station. We invert for a smooth map of t* from the ensemble of measurements. The spatial patterns in t* correlate very well with the tectonic domains in Spain and Morocco. In particular, areas in Spain that resisted deformation during the Variscan and Alpine orogenies produce very little attenuation. Comparing the attenuation map with seismic velocity structure we find that, in Morocco, some areas with strong low-velocity anomalies and recent volcanism do not cause high attenuation. These observations suggest that water content is a more likely cause for seismic attenuation in the study area than temperature, and that the non-attenuative low-velocity anomalies in Morocco are produced by partial mel.

  16. Variations in Microbial Community Structure through the Stratified Water Column in the Tyrrhenian Sea (Central Mediterranean

    Directory of Open Access Journals (Sweden)

    Francesco Smedile

    2015-08-01

    Full Text Available The central Mediterranean Sea is among the most oligotrophic habitats in the marine environment. In this study, we investigated the abundance, diversity and activity of prokaryoplankton in the water column (25–3000-m depth at Station Vector (Tyrrhenian Sea, 39°32.050′ N; 13°22.280′ E. This specific water column consists of three different water masses (Modified Atlantic Water (MAW, Levantine Intermediate Water (LIW and Tyrrhenian Deep Water (TDW, possessing a typical stratification of the Central Mediterranean basin. CARD-FISH showed that the metabolically-active fraction of bacterial populations exceeded the archaeal fraction along the whole water column, except at the deepest water masses. 16S rDNA and 16S rRNA clone libraries obtained from each type of water mass were used to analyse the prokaryoplankton community structure and to distinguish between active and “less active” microbial fractions. Our results showed that the rRNA-derived bacterial libraries seemed to be more depth specific compared to 16S rDNA-derived counterparts. Major differences were detected between the active fractions of bacterioplankton thriving in photic (25 m, MAW and aphotic layers (500–3000 m, LIW and TDW respectively, whereas no statistically-significant differences were detected within the deep, aphotic layers (500–3000 m, LIW and TDW. Archaeal communities possessed more depth-specific distribution patterns with both total and active fractions showing depth stratification. Cyanobacteria and Marine Group II MAGII of Euryarchaea dominated the MAW prokaryoplankton. A notable fraction of Geitlerinema-related cyanobacteria was detected among the metabolically-active bacterial population recovered from the mesopelagic (500 m, LIW aphotic layer, which is indicative of their mixotrophic behaviour. Heterotrophic Gammaproteobacteria and members of Marine Group 1.1a and the PSL12-related ALOHA group of Thaumarchaeota were both abundant in the aphotic layers

  17. Al-Qaeda arrest casts shadow over the LHC

    CERN Multimedia

    Dacey, James

    2010-01-01

    "Cern remains on course for the imminent switch-on of the Large Hadron Collider (LHC) despite the media frenzy following the recent arrest of a physicist who had been working at the facility. The researcher in question is a 32-year-old man of Algerian descent who is expected to face trail in France - the country in which he was arrested" (0.5 page)

  18. Impact of regression methods on improved effects of soil structure on soil water retention estimates

    Science.gov (United States)

    Nguyen, Phuong Minh; De Pue, Jan; Le, Khoa Van; Cornelis, Wim

    2015-06-01

    Increasing the accuracy of pedotransfer functions (PTFs), an indirect method for predicting non-readily available soil features such as soil water retention characteristics (SWRC), is of crucial importance for large scale agro-hydrological modeling. Adding significant predictors (i.e., soil structure), and implementing more flexible regression algorithms are among the main strategies of PTFs improvement. The aim of this study was to investigate whether the improved effect of categorical soil structure information on estimating soil-water content at various matric potentials, which has been reported in literature, could be enduringly captured by regression techniques other than the usually applied linear regression. Two data mining techniques, i.e., Support Vector Machines (SVM), and k-Nearest Neighbors (kNN), which have been recently introduced as promising tools for PTF development, were utilized to test if the incorporation of soil structure will improve PTF's accuracy under a context of rather limited training data. The results show that incorporating descriptive soil structure information, i.e., massive, structured and structureless, as grouping criterion can improve the accuracy of PTFs derived by SVM approach in the range of matric potential of -6 to -33 kPa (average RMSE decreased up to 0.005 m3 m-3 after grouping, depending on matric potentials). The improvement was primarily attributed to the outperformance of SVM-PTFs calibrated on structureless soils. No improvement was obtained with kNN technique, at least not in our study in which the data set became limited in size after grouping. Since there is an impact of regression techniques on the improved effect of incorporating qualitative soil structure information, selecting a proper technique will help to maximize the combined influence of flexible regression algorithms and soil structure information on PTF accuracy.

  19. Shear-stress-induced structural arrangement of water molecules in nanoscale Couette flow with slipping at wall boundary

    International Nuclear Information System (INIS)

    Lin, Jau-Wen

    2014-01-01

    This study investigated the structuring of water molecules in a nanoscale Couette flow with the upper plate subjected to lateral forces with various magnitudes and water slipping against a metal wall. It was found that when the upper plate is subjected to a force, the water body deforms into a parallelepiped. Water molecules in the channel are then gradually arranged into lattice positions, creating a layered structure. The structural arrangement of water molecules is caused by the water molecules accommodating themselves to the increase in energy under the application of a lateral force on the moving plate. The ordering arrangement of water molecules increases the rotational degree of freedom, allowing the molecules to increase their Coulomb potential energy through polar rotation that accounts for the energy input through the upper plate. With a force continuously applied to the upper plate, the water molecules in contact with the upper plate move forward until slip between the water and upper plate occurs. The relation between the structural arrangement of water molecules, slip at the wall, and the shear force is studied. The relation between the slip and the locking/unlocking of water molecules to metal atoms is also studied

  20. Associates of Cardiopulmonary Arrest in the Perihemodialytic Period

    Science.gov (United States)

    Flythe, Jennifer E.; Li, Nien-Chen; Brunelli, Steven M.; Lacson, Eduardo

    2014-01-01

    Cardiopulmonary arrest during and proximate to hemodialysis is rare but highly fatal. Studies have examined peridialytic sudden cardiac event risk factors, but no study has considered associates of cardiopulmonary arrests (fatal and nonfatal events including cardiac and respiratory causes). This study was designed to elucidate patient and procedural factors associated with peridialytic cardiopulmonary arrest. Data for this case-control study were taken from the hemodialysis population at Fresenius Medical Care, North America. 924 in-center cardiopulmonary events (cases) and 75,538 controls were identified. Cases and controls were 1 : 5 matched on age, sex, race, and diabetes. Predictors of cardiopulmonary arrest were considered for logistic model inclusion. Missed treatments due to hospitalization, lower body mass, coronary artery disease, heart failure, lower albumin and hemoglobin, lower dialysate potassium, higher serum calcium, greater erythropoietin stimulating agent dose, and normalized protein catabolic rate (J-shaped) were associated with peridialytic cardiopulmonary arrest. Of these, lower albumin, hemoglobin, and body mass index; higher erythropoietin stimulating agent dose; and greater missed sessions had the strongest associations with outcome. Patient health markers and procedural factors are associated with peridialytic cardiopulmonary arrest. In addition to optimizing nutritional status, it may be prudent to limit exposure to low dialysate potassium (<2 K bath) and to use the lowest effective erythropoietin stimulating agent dose. PMID:25530881

  1. Associates of Cardiopulmonary Arrest in the Perihemodialytic Period

    Directory of Open Access Journals (Sweden)

    Jennifer E. Flythe

    2014-01-01

    Full Text Available Cardiopulmonary arrest during and proximate to hemodialysis is rare but highly fatal. Studies have examined peridialytic sudden cardiac event risk factors, but no study has considered associates of cardiopulmonary arrests (fatal and nonfatal events including cardiac and respiratory causes. This study was designed to elucidate patient and procedural factors associated with peridialytic cardiopulmonary arrest. Data for this case-control study were taken from the hemodialysis population at Fresenius Medical Care, North America. 924 in-center cardiopulmonary events (cases and 75,538 controls were identified. Cases and controls were 1 : 5 matched on age, sex, race, and diabetes. Predictors of cardiopulmonary arrest were considered for logistic model inclusion. Missed treatments due to hospitalization, lower body mass, coronary artery disease, heart failure, lower albumin and hemoglobin, lower dialysate potassium, higher serum calcium, greater erythropoietin stimulating agent dose, and normalized protein catabolic rate (J-shaped were associated with peridialytic cardiopulmonary arrest. Of these, lower albumin, hemoglobin, and body mass index; higher erythropoietin stimulating agent dose; and greater missed sessions had the strongest associations with outcome. Patient health markers and procedural factors are associated with peridialytic cardiopulmonary arrest. In addition to optimizing nutritional status, it may be prudent to limit exposure to low dialysate potassium (<2 K bath and to use the lowest effective erythropoietin stimulating agent dose.

  2. Cardiac arrest due to lymphocytic colitis: a case report

    Directory of Open Access Journals (Sweden)

    Groth Kristian A

    2012-03-01

    Full Text Available Abstract Introduction We present a case of cardiac arrest due to hypokalemia caused by lymphocytic colitis. Case presentation A 69-year-old Caucasian man presented four months prior to a cardiac arrest with watery diarrhea and was diagnosed with lymphocytic colitis. Our patient experienced a witnessed cardiac arrest at his general practitioner's surgery. Two physicians and the emergency medical services resuscitated our patient for one hour and four minutes before arriving at our university hospital. Our patient was defibrillated 16 times due to the recurrence of ventricular tachyarrhythmias. An arterial blood sample revealed a potassium level of 2.0 mmol/L (reference range: 3.5 to 4.6 mmol/L and pH 6.86 (reference range: pH 7.37 to 7.45. As the potassium level was corrected, the propensity for ventricular tachyarrhythmias ceased. Our patient recovered from his cardiac arrest without any neurological deficit. Further tests and examinations revealed no other reason for the cardiac arrest. Conclusion Diarrhea can cause life-threatening situations due to the excretion of potassium, ultimately causing cardiac arrest due to hypokalemia. Physicians treating patients with severe diarrhea should consider monitoring their electrolyte levels.

  3. Early prognostication markers in cardiac arrest patients treated with hypothermia.

    Science.gov (United States)

    Karapetkova, M; Koenig, M A; Jia, X

    2016-03-01

    Established prognostication markers, such as clinical findings, electroencephalography (EEG) and biochemical markers, used by clinicians to predict neurological outcome after cardiac arrest (CA) are altered under therapeutic hypothermia (TH) conditions and their validity remains uncertain. MEDLINE and Embase were searched for evidence on the current standards for neurological outcome prediction for out-of-hospital CA patients treated with TH and the validity of a wide range of prognostication markers. Relevant studies that suggested one or several established biomarkers and multimodal approaches for prognostication are included and reviewed. Whilst the prognostic accuracy of various tests after TH has been questioned, pupillary light reflexes and somatosensory evoked potentials are still strongly associated with negative outcome for early prognostication. Increasingly, EEG background activity has also been identified as a valid predictor for outcome after 72 h after CA and a preferred prognostic method in clinical settings. Neuroimaging techniques, such as magnetic resonance imaging and computed tomography, can identify functional and structural brain injury but are not readily available at the patient's bedside because of limited availability and high costs. A multimodal algorithm composed of neurological examination, EEG-based quantitative testing and somatosensory evoked potentials, in conjunction with newer magnetic resonance imaging sequences, if available, holds promise for accurate prognostication in CA patients treated with TH. In order to avoid premature withdrawal of care, prognostication should be performed more than 72 h after CA. © 2015 EAN.

  4. Effect of hardening methods of moulding sands with water glass on structure of bonding bridges

    Directory of Open Access Journals (Sweden)

    M. Stachowicz

    2010-07-01

    Full Text Available Research on influence of hardening methods on structure of bonding bridges in moulding sands with sodium water glass is presented.Moulding sands with addition of 2.5 % of binder with molar module 2.0 were hardened with CO2 and dried in traditional way or hardenedwith microwaves. It was proved that the hardening method affects structure of bonding bridges, correlating with properties of the hardened moulding sands. It was found that strength of the moulding sands hardened with microwaves for 4 min is very close to that measured after traditional drying at 110 °C for 120 min. So, application of microwave hardening ensures significant shortening of the process time to the value comparable with CO2 hardening but guaranteeing over 10-fold increase of mechanical properties. Analysis of SEM images of hardened moulding sands permitted explaining differences in quality parameters of moulding sands by connecting them with structure of the created bonding bridges.

  5. Theoretical and experimental investigation into structural and fluid motions at low frequencies in water distribution pipes

    Science.gov (United States)

    Gao, Yan; Liu, Yuyou

    2017-06-01

    Vibrational energy is transmitted in buried fluid-filled pipes in a variety of wave types. Axisymmetric (n = 0) waves are of practical interest in the application of acoustic techniques for the detection of leaks in underground pipelines. At low frequencies n = 0 waves propagate longitudinally as fluid-dominated (s = 1) and shell-dominated (s = 2) waves. Whilst sensors such as hydrophones and accelerometers are commonly used to detect leaks in water distribution pipes, the mechanism governing the structural and fluid motions is not well documented. In this paper, the low-frequency behaviour of the pipe wall and the contained fluid is investigated. For most practical pipework systems, these two waves are strongly coupled; in this circumstance the ratios of the radial pipe wall displacements along with the internal pressures associated with these two wave types are obtained. Numerical examples show the relative insensitivity of the structural and fluid motions to the s = 2 wave for both metallic and plastic pipes buried in two typical soils. It is also demonstrated that although both acoustic and vibration sensors at the same location provide the identical phase information of the transmitted signals, pressure responses have significantly higher levels than acceleration responses, and thus hydrophones are better suited in a low signal-to-noise ratio (SNR) environment. This is supported by experimental work carried out at a leak detection facility. Additional pressure measurements involved excitation of the fluid and the pipe fitting (hydrant) on a dedicated water pipe. This work demonstrates that the s = 1 wave is mainly responsible for the structural and fluid motions at low frequencies in water distribution pipes as a result of water leakage and direct pipe excitation.

  6. Impact of water temperature and structural parameters on the hydraulic labyrinth-channel emitter performance

    Directory of Open Access Journals (Sweden)

    Ahmed I. Al-Amoud

    2014-06-01

    Full Text Available The effects of water temperature and structural parameters of a labyrinth emitter on drip irrigation hydraulic performance were investigated. The inside structural parameters of the trapezoidal labyrinth emitter include path width (W and length (L, trapezoidal unit numbers (N, height (H, and spacing (S. Laboratory experiments were conducted using five different types of labyrinth-channel emitters (three non-pressure compensating and two pressure-compensating emitters commonly used for subsurface drip irrigation systems. The water temperature effect on the hydraulic characteristics at various operating pressures was recorded and a comparison was made to identify the most effective structural parameter on emitter performance. The pressure compensating emitter flow exponent (x average was 0.014, while non-pressure compensating emitter’s values average was 0.456, indicating that the sensitivity of non-pressure compensating emitters to pressure variation is an obvious characteristic (p<0.001 of this type of emitters. The effects of water temperature on emitter flow rate were insignificant (p>0.05 at various operating pressures, where the flow rate index values for emitters were around one. The effects of water temperature on manufacturer’s coefficient of variation (CV values for all emitters were insignificant (p>0.05. The CV values of the non-pressure compensating emitters were lower than those of pressure compensating emitters. This is typical for most compensating models because they are manufactured with more elements than non-compensating emitters are. The results of regression analysis indicate that N and H are the essential factors (p<0.001 to affect the hydraulic performance.

  7. Artificial neural networks aided conceptual stage design of water harvesting structures

    Directory of Open Access Journals (Sweden)

    Vinay Chandwani

    2016-09-01

    Full Text Available The paper presents artificial neural networks (ANNs based methodology for ascertaining the structural parameters of water harvesting structures (WHS at the conceptual stage of design. The ANN is trained using exemplar patterns generated using an in-house MSExcel based design program, to draw a functional relationship between the five inputs design parameters namely, peak flood discharge, safe bearing capacity of strata, length of structure, height of structure and silt factor and four outputs namely, top width, bottom width, foundation depth and flood lift representing the structural parameters of WHS. The results of the study show that, the structural parameters of the WHS predicted using ANN model are in close agreement with the actual field parameters. The versatility of ANN to map complex or complex unknown relationships has been proven in the study. A parametric sensitivity study is also performed to assess the most significant design parameter. The study holistically presents a neural network based decision support tool that can be used to accurately estimate the major design parameters of the WHS at the conceptual stage of design in quick time, aiding the engineer-in-charge to conveniently forecast the budget requirements and minimize the labor involved during the subsequent phases of analysis and design.

  8. A model of survival following pre-hospital cardiac arrest based on the Victorian Ambulance Cardiac Arrest Register.

    Science.gov (United States)

    Fridman, Masha; Barnes, Vanessa; Whyman, Andrew; Currell, Alex; Bernard, Stephen; Walker, Tony; Smith, Karen L

    2007-11-01

    This study describes the epidemiology of sudden cardiac arrest patients in Victoria, Australia, as captured via the Victorian Ambulance Cardiac Arrest Register (VACAR). We used the VACAR data to construct a new model of out-of-hospital cardiac arrest (OHCA), which was specified in accordance with observed trends. All cases of cardiac arrest in Victoria that were attended by Victorian ambulance services during the period of 2002-2005. Overall survival to hospital discharge was 3.8% among 18,827 cases of OHCA. Survival was 15.7% among 1726 bystander witnessed, adult cardiac arrests of presumed cardiac aetiology, presenting in ventricular fibrillation or ventricular tachycardia (VF/VT), where resuscitation was attempted. In multivariate logistic regression analysis, bystander CPR, cardiac arrest (CA) location, response time, age and sex were predictors of VF/VT, which, in turn, was a strong predictor of survival. The same factors that affected VF/VT made an additional contribution to survival. However, for bystander CPR, CA location and response time this additional contribution was limited to VF/VT patients only. There was no detectable association between survival and age younger than 60 years or response time over 15min. The new model accounts for relationships among predictors of survival. These relationships indicate that interventions such as reduced response times and bystander CPR act in multiple ways to improve survival.

  9. Characterization of Mitochondrial Injury after Cardiac Arrest (COMICA)

    Science.gov (United States)

    Donnino, Michael W.; Liu, Xiaowen; Andersen, Lars W.; Rittenberger, Jon C.; Abella, Benjamin S.; Gaieski, David F.; Ornato, Joseph P.; Gazmuri, Raúl J.; Grossestreur, Anne V.; Cocchi, Michaen N.; Abbate, Antonio; Uber, Amy; Clore, John; Peberdy, Mary Anne; Callaway, Clifton

    2017-01-01

    Introduction Mitochondrial injury post-cardiac arrest has been described in pre-clinical settings but the extent to which this injury occurs in humans remains largely unknown. We hypothesized that increased levels of mitochondrial biomarkers would be associated with mortality and neurological morbidity in post-cardiac arrest subjects. Methods We performed a prospective multicenter study of post-cardiac arrest subjects. Inclusion criteria were comatose adults who suffered an out-of-hospital cardiac arrest. Mitochondrial biomarkers were measured at 0, 12, 24, 36 and 48 hours after return of spontaneous circulation as well as in healthy controls. Results Out of 111 subjects enrolled, 102 had evaluable samples at 0 hours. Cardiac arrest subjects had higher baseline cytochrome c levels compared to controls (2.18 ng/mL [0.74, 7.74] vs. 0.16 ng/mL [0.03, 0.91], p<0.001), and subjects who died had higher 0 hours cytochrome c levels compared to survivors (3.66 ng/mL [1.40, 14.9] vs. 1.27 ng/mL [0.16, 2.37], p<0.001). There were significantly higher RNAase P (3.3 [1.2, 5.7] vs. 1.2 [0.8, 1.2], p<0.001) and B2M (12.0 [1.0, 22.9], vs. 0.6 [0.6, 1.3], p<0.001) levels in cardiac arrest subjects at baseline compared to the control subjects. There were no differences between survivors and non-survivors for mitochondrial DNA, nuclear DNA, or cell free DNA. Conclusions Cytochrome C was increased in post-cardiac arrest subjects compared to controls, and in post-cardiac arrest non-survivors compared to survivors. Nuclear DNA and cell free DNA was increased in plasma of post-cardiac arrest subjects. There were no differences in mitochondrial DNA, nuclear DNA, or cell free DNA between survivors and non-survivors. Mitochondrial injury markers showed mixed results in post-arrest period. Future research needs to investigate these differences. PMID:28126408

  10. Characterization of mitochondrial injury after cardiac arrest (COMICA).

    Science.gov (United States)

    Donnino, Michael W; Liu, Xiaowen; Andersen, Lars W; Rittenberger, Jon C; Abella, Benjamin S; Gaieski, David F; Ornato, Joseph P; Gazmuri, Raúl J; Grossestreuer, Anne V; Cocchi, Michael N; Abbate, Antonio; Uber, Amy; Clore, John; Peberdy, Mary Anne; Callaway, Clifton W

    2017-04-01

    Mitochondrial injury post-cardiac arrest has been described in pre-clinical settings but the extent to which this injury occurs in humans remains largely unknown. We hypothesized that increased levels of mitochondrial biomarkers would be associated with mortality and neurological morbidity in post-cardiac arrest subjects. We performed a prospective multicenter study of post-cardiac arrest subjects. Inclusion criteria were comatose adults who suffered an out-of-hospital cardiac arrest. Mitochondrial biomarkers were measured at 0, 12, 24, 36 and 48h after return of spontaneous circulation as well as in healthy controls. Out of 111 subjects enrolled, 102 had evaluable samples at 0h. Cardiac arrest subjects had higher baseline cytochrome c levels compared to controls (2.18ng/mL [0.74, 7.74] vs. 0.16ng/mL [0.03, 0.91], p<0.001), and subjects who died had higher 0h cytochrome c levels compared to survivors (3.66ng/mL [1.40, 14.9] vs. 1.27ng/mL [0.16, 2.37], p<0.001). There were significantly higher Ribonuclease P (RNaseP) (3.3 [1.2, 5.7] vs. 1.2 [0.8, 1.2], p<0.001) and Beta-2microglobulin (B2M) (12.0 [1.0, 22.9], vs. 0.6 [0.6, 1.3], p<0.001) levels in cardiac arrest subjects at baseline compared to the control subjects. There were no differences between survivors and non-survivors for mitochondrial DNA, nuclear DNA, or cell free DNA. Cytochrome c was increased in post- cardiac arrest subjects compared to controls, and in post-cardiac arrest non-survivors compared to survivors. Nuclear DNA and cell free DNA was increased in plasma of post-cardiac arrest subjects. There were no differences in mitochondrial DNA, nuclear DNA, or cell free DNA between survivors and non-survivors. Mitochondrial injury markers showed mixed results in the post-cardiac arrest period. Future research needs to investigate these differences. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Nuclear reactor pressure vessel integrity insurance by crack arrestability evaluation using load from CVN tests

    International Nuclear Information System (INIS)

    Fabry, A.

    1997-01-01

    The present work is undertaken in the framework of nuclear reactor pressure vessel (RPV) surveillance and aims at revisiting the crack arrest approach to structural integrity insurance. This approach, performed under normal plant operation conditions, can also offer an attractive alternative to the crack initiation philosophy promoted for accidental analysis. To this end, an accidental conservative, cost effective and robust methodology is forwarded and demonstrated: it makes use of the crack arrest information contained in the instrumented Charpy V-notch impact test and/or in the shear fracture appearance of broken samples. Particular attention is paid to the appraisal of uncertainties and the related safety margin. The resulting capability is placed in perspective with the state-of-the-art crack initiation methodology based on the slow bend testing of recracked specimens, presently under standardization world-wide. The investigation leads to highlight three conceptual weaknesses of current enfgineering and regulatory practices. Improved crack arrestability evaluation emerges as an optimal approach to insure safe PWR operation up to design end-of-life and beyond

  12. Nuclear reactor pressure vessel integrity insurance by crack arrestability evaluation using load from CVN tests

    Energy Technology Data Exchange (ETDEWEB)

    Fabry, A.

    1997-10-15

    The present work is undertaken in the framework of nuclear reactor pressure vessel (RPV) surveillance and aims at revisiting the crack arrest approach to structural integrity insurance. This approach, performed under normal plant operation conditions, can also offer an attractive alternative to the crack initiation philosophy promoted for accidental analysis. To this end, an accidental conservative, cost effective and robust methodology is forwarded and demonstrated: it makes use of the crack arrest information contained in the instrumented Charpy V-notch impact test and/or in the shear fracture appearance of broken samples. Particular attention is paid to the appraisal of uncertainties and the related safety margin. The resulting capability is placed in perspective with the state-of-the-art crack initiation methodology based on the slow bend testing of recracked specimens, presently under standardization world-wide. The investigation leads to highlight three conceptual weaknesses of current enfgineering and regulatory practices. Improved crack arrestability evaluation emerges as an optimal approach to insure safe PWR operation up to design end-of-life and beyond.

  13. Aqueous turbulence structure immediately adjacent to the air - water interface and interfacial gas exchange

    Science.gov (United States)

    Wang, Binbin

    Air-sea interaction and the interfacial exchange of gas across the air-water interface are of great importance in coupled atmospheric-oceanic environmental systems. Aqueous turbulence structure immediately adjacent to the air-water interface is the combined result of wind, surface waves, currents and other environmental forces and plays a key role in energy budgets, gas fluxes and hence the global climate system. However, the quantification of turbulence structure sufficiently close to the air-water interface is extremely difficult. The physical relationship between interfacial gas exchange and near surface turbulence remains insufficiently investigated. This dissertation aims to measure turbulence in situ in a complex environmental forcing system on Lake Michigan and to reveal the relationship between turbulent statistics and the CO2 flux across the air-water interface. The major objective of this dissertation is to investigate the physical control of the interfacial gas exchange and to provide a universal parameterization of gas transfer velocity from environmental factors, as well as to propose a mechanistic model for the global CO2 flux that can be applied in three dimensional climate-ocean models. Firstly, this dissertation presents an advanced measurement instrument, an in situ free floating Particle Image Velocimetry (FPIV) system, designed and developed to investigate the small scale turbulence structure immediately below the air-water interface. Description of hardware components, design of the system, measurement theory, data analysis procedure and estimation of measurement error were provided. Secondly, with the FPIV system, statistics of small scale turbulence immediately below the air-water interface were investigated under a variety of environmental conditions. One dimensional wave-number spectrum and structure function sufficiently close to the water surface were examined. The vertical profiles of turbulent dissipation rate were intensively studied

  14. Nano-structured silica coated mesoporous carbon micro-granules for potential application in water filtration

    Science.gov (United States)

    Das, Avik; Sen, D.; Mazumder, S.; Ghosh, A. K.

    2017-05-01

    A novel nano-composite spherical micro-granule has been synthesized using a facile technique of solvent evaporation induced assembly of nanoparticles for potential application in water filtration. The spherical micro-granule is comprised of nano-structured shell of hydrophilic silica encapsulating a hydrophobic mesoporous carbon at the core. Hierarchical structure of such core-shell micro-granules has been rigorously characterized using small-angle neutron and X-ray scattering techniques and complemented with scanning electron microscopy. The hydrophilic silica envelope around the carbon core helps in incorporation of such granules into the hydrophilic polymeric ultra-filtration membrane. The interstitial micro-pores present in the silica shell can serve as water transport channels and the mesoporus carbon core enhances the separation performance due its well adsorption characteristics. It has been found that the incorporation of such granules inside the ultra-filtration membrane indeed enhances the water permeability as well as the separation performance in a significant way.

  15. Role of water on formation and structural features of Maya blue

    International Nuclear Information System (INIS)

    Mondelli, C; Río, M Sánchez del; González, M A; Magazzú, A; Cavallari, C; Suárez, M; García-Romero, E; Romano, P

    2012-01-01

    The Maya blue (MB) is an artificial pigment created between 500-800 A.D. and used in murals, pottery and sculptures by Mayas and other people in Mesoamerica. MB is resistant to age, acid, weathering, biodegradation and even modern chemical solvents, but the chemical reasons behind the resistance to chemical aggressions are still under debate. Water plays a fundamental role in the interactions between indigo and clay. The dynamics of the clay's zeolitic and structural water molecules during the formation of MB, usually stabilized by moderate heating, has been monitored by means of neutron inelastic scattering. Neutron incoherent scattering in these samples is only due to the hydrogen atoms, so the signal is very sensitive to the amount of released water, providing detailed information on the dehydration process. A simultaneous analysis of the coherent elastic scattering and the incoherent scattering allows observing and quantifying how the structure of the clay is affected by dehydration. Here we show that a quite resistant pigment can be obtained at room temperature simply by dehydrating a palygorskite-indigo mixture employing only vacuum, without any thermal treatment.

  16. Distortions of the calcite and aragonite atomic structures from interstitial water

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, S.; Rez, P., E-mail: Peter.Rez@asu.edu

    2015-05-01

    Amorphous calcium carbonate (ACC), as observed by diffraction or infra-red spectroscopy, is especially significant as a precursor in biomineralization. The atomic structure and mechanisms for transformation to the crystalline phases are still unknown. It is conceivable that insertion of water molecules could give rise to distortions that result in the observed diffraction patterns and infrared spectra. We use the VASP density functional theory code to relax model supercells with 24 formula units of CaCO{sub 3} where we have inserted up to 5 water molecules, corresponding to 3.75 wt%. The main effect is tilting of the carbonate planes, which can be as high as 50°. This leads to a range of Ca–O distances that are consistent with the observed changes in the IR spectra in ACC. The spread in cation–cation distances is not enough to destroy coherent diffraction from regions 70 nm across, and so does not explain amorphous diffraction profiles. - Highlights: • Low concentrations of water in the calcite or aragonite structures lead to tilting of the carbonate planes. • This is consistent with IR observations from amorphous calcium carbonate. • It does not explain amorphous diffraction patterns.

  17. Role of water on formation and structural features of Maya blue

    Science.gov (United States)

    Mondelli, C.; Sánchez del Río, M.; González, M. A.; Magazzú, A.; Cavallari, C.; Suárez, M.; García-Romero, E.; Romano, P.

    2012-02-01

    The Maya blue (MB) is an artificial pigment created between 500-800 A.D. and used in murals, pottery and sculptures by Mayas and other people in Mesoamerica. MB is resistant to age, acid, weathering, biodegradation and even modern chemical solvents, but the chemical reasons behind the resistance to chemical aggressions are still under debate. Water plays a fundamental role in the interactions between indigo and clay. The dynamics of the clay's zeolitic and structural water molecules during the formation of MB, usually stabilized by moderate heating, has been monitored by means of neutron inelastic scattering. Neutron incoherent scattering in these samples is only due to the hydrogen atoms, so the signal is very sensitive to the amount of released water, providing detailed information on the dehydration process. A simultaneous analysis of the coherent elastic scattering and the incoherent scattering allows observing and quantifying how the structure of the clay is affected by dehydration. Here we show that a quite resistant pigment can be obtained at room temperature simply by dehydrating a palygorskite-indigo mixture employing only vacuum, without any thermal treatment.

  18. Structural Investigation of Alkali Activated Clay Minerals for Application in Water Treatment Systems

    Science.gov (United States)

    Bumanis, G.; Bajare, D.; Dembovska, L.

    2015-11-01

    Alkali activation technology can be applied for a wide range of alumo-silicates to produce innovative materials with various areas of application. Most researches focuse on the application of alumo-silicate materials in building industry as cement binder replacement to produce mortar and concrete [1]. However, alkali activation technology offers high potential also in biotechnologies [2]. In the processes where certain pH level, especially alkaline environment, must be ensured, alkali activated materials can be applied. One of such fields is water treatment systems where high level pH (up to pH 10.5) ensures efficient removal of water pollutants such as manganese [3]. Previous investigations had shown that alkali activation technology can be applied to calcined clay powder and aluminium scrap recycling waste as a foam forming agent to create porous alkali activated materials. This investigation focuses on the structural investigation of calcined kaolin and illite clay alkali activation processes. Chemical and mineralogical composition of both clays were determined and structural investigation of alkali activated materials was made by using XRD, DTA, FTIR analysis; the microstructure of hardened specimens was observed by SEM. Physical properties of the obtained material were determined. Investigation indicates the essential role of chemical composition of the clay used in the alkali activation process, and potential use of the obtained material in water treatment systems.

  19. Seismic response of elevated rectangular water tanks considering soil structure interaction

    Science.gov (United States)

    Visuvasam, J.; Simon, J.; Packiaraj, J. S.; Agarwal, R.; Goyal, L.; Dhingra, V.

    2017-11-01

    The overhead staged water tanks are susceptible for high lateral forces during earthquakes. Due to which, the failure of beam-columns joints, framing elements and toppling of tanks arise. To avoid such failures, they are analyzed and designed for lateral forced induced by devastating earthquakes assuming the base of the structures are fixed and considering functional needs, response reduction, soil types and severity of ground shaking. In this paper, the flexible base was provided as spring stiffness in order to consider the effect of soil properties on the seismic behaviour of water tanks. A linear time history earthquake analysis was performed using SAP2000. Parametric studies have been carried out based on various types of soils such as soft, medium and hard. The soil stiffness values highly influence the time period and base shear of the structure. The ratios of time period of flexible to fixed base and base shear of flexible to fixed base were observed against capacities of water tank and the overall height of the system. The both responses are found to be increased as the flexibility of soil medium decreases

  20. Structure and dynamics of POPC bilayers in water solutions of room temperature ionic liquids

    International Nuclear Information System (INIS)

    Benedetto, Antonio; Bingham, Richard J.; Ballone, Pietro

    2015-01-01

    Molecular dynamics simulations in the NPT ensemble have been carried out to investigate the effect of two room temperature ionic liquids (RTILs), on stacks of phospholipid bilayers in water. We consider RTIL compounds consisting of chloride ([bmim][Cl]) and hexafluorophosphate ([bmim][PF 6 ]) salts of the 1-buthyl-3-methylimidazolium ([bmim] + ) cation, while the phospholipid bilayer is made of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC). Our investigations focus on structural and dynamical properties of phospholipid and water molecules that could be probed by inelastic and quasi-elastic neutron scattering measurements. The results confirm the fast incorporation of [bmim] + into the lipid phase already observed in previous simulations, driven by the Coulomb attraction of the cation for the most electronegative oxygens in the POPC head group and by sizeable dispersion forces binding the neutral hydrocarbon tails of [bmim] + and of POPC. The [bmim] + absorption into the bilayer favours the penetration of water into POPC, causes a slight but systematic thinning of the bilayer, and further stabilises hydrogen bonds at the lipid/water interface that already in pure samples (no RTIL) display a lifetime much longer than in bulk water. On the other hand, the effect of RTILs on the diffusion constant of POPC (D POPC ) does not reveal a clearly identifiable trend, since D POPC increases upon addition of [bmim][Cl] and decreases in the [bmim][PF 6 ] case. Moreover, because of screening, the electrostatic signature of each bilayer is only moderately affected by the addition of RTIL ions in solution. The analysis of long wavelength fluctuations of the bilayers shows that RTIL sorption causes a general decrease of the lipid/water interfacial tension and bending rigidity, pointing to the destabilizing effect of RTILs on lipid bilayers

  1. Structure and dynamics of POPC bilayers in water solutions of room temperature ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Benedetto, Antonio [School of Physics, University College Dublin, Dublin 4 (Ireland); Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen (Switzerland); Bingham, Richard J. [York Centre for Complex Systems Analysis, University of York, York YO10 5GE (United Kingdom); Ballone, Pietro [Center for Life Nano Science @Sapienza, Istituto Italiano di Tecnologia (IIT), 00185 Roma (Italy); Department of Physics, Università di Roma “La Sapienza,” 00185 Roma (Italy)

    2015-03-28

    Molecular dynamics simulations in the NPT ensemble have been carried out to investigate the effect of two room temperature ionic liquids (RTILs), on stacks of phospholipid bilayers in water. We consider RTIL compounds consisting of chloride ([bmim][Cl]) and hexafluorophosphate ([bmim][PF{sub 6}]) salts of the 1-buthyl-3-methylimidazolium ([bmim]{sup +}) cation, while the phospholipid bilayer is made of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC). Our investigations focus on structural and dynamical properties of phospholipid and water molecules that could be probed by inelastic and quasi-elastic neutron scattering measurements. The results confirm the fast incorporation of [bmim]{sup +} into the lipid phase already observed in previous simulations, driven by the Coulomb attraction of the cation for the most electronegative oxygens in the POPC head group and by sizeable dispersion forces binding the neutral hydrocarbon tails of [bmim]{sup +} and of POPC. The [bmim]{sup +} absorption into the bilayer favours the penetration of water into POPC, causes a slight but systematic thinning of the bilayer, and further stabilises hydrogen bonds at the lipid/water interface that already in pure samples (no RTIL) display a lifetime much longer than in bulk water. On the other hand, the effect of RTILs on the diffusion constant of POPC (D{sub POPC}) does not reveal a clearly identifiable trend, since D{sub POPC} increases upon addition of [bmim][Cl] and decreases in the [bmim][PF{sub 6}] case. Moreover, because of screening, the electrostatic signature of each bilayer is only moderately affected by the addition of RTIL ions in solution. The analysis of long wavelength fluctuations of the bilayers shows that RTIL sorption causes a general decrease of the lipid/water interfacial tension and bending rigidity, pointing to the destabilizing effect of RTILs on lipid bilayers.

  2. Heterogeneous structure and solvation dynamics of DME/water binary mixtures: A combined spectroscopic and simulation investigation

    Science.gov (United States)

    Das Mahanta, Debasish; Rana, Debkumar; Patra, Animesh; Mukherjee, Biswaroop; Mitra, Rajib Kumar

    2018-05-01

    Water is often found in (micro)-heterogeneous environments and therefore it is necessary to understand their H-bonded network structure in such altered environments. We explore the structure and dynamics of water in its binary mixture with relatively less polar small biocompatible amphiphilic molecule 1,2-Dimethoxyethane (DME) by a combined spectroscopic and molecular dynamics (MD) simulation study. Picosecond (ps) resolved fluorescence spectroscopy using coumarin 500 as the fluorophore establishes a non-monotonic behaviour of the mixture. Simulation studies also explore the various possible H-bond formations between water and DME. The relative abundance of such different water species manifests the heterogeneity in the mixture.

  3. Classification and assessment of water bodies as adaptive structural measures for flood risk management planning.

    Science.gov (United States)

    McMinn, William R; Yang, Qinli; Scholz, Miklas

    2010-09-01

    Severe rainfall events have become increasingly common in Europe. Flood defence engineering works are highly capital intensive and can be limited by land availability, leaving land and communities exposed to repeated flooding. Any adaptive drainage structure must have engineered inlets and outlets that control the water level and the rate of release. In Scotland, there are a relatively high number of drinking water reservoirs (operated by Scottish Water), which fall within this defined category and could contribute to flood management control. Reducing the rate of runoff from the upper reaches of a catchment will reduce the volume and peak flows of flood events downstream, thus allowing flood defences to be reduced in size, decreasing the corresponding capital costs. A database of retention basins with flood control potential has been developed for Scotland. The research shows that the majority of small and former drinking water reservoirs are kept full and their spillways are continuously in operation. Utilising some of the available capacity to contribute to flood control could reduce the costs of complying with the EU Flood Directive. Furthermore, the application of a previously developed classification model for Baden in Germany for the Scottish data set showed a lower diversity for basins in Scotland due to less developed infrastructure. The principle value of this approach is a clear and unambiguous categorisation, based on standard variables, which can help to promote communication and understanding between stakeholders. 2010 Elsevier Ltd. All rights reserved.

  4. Implementation of the national desalination and water purification technology roadmap : structuring and directing the development of water supply solutions.

    Energy Technology Data Exchange (ETDEWEB)

    Price, Kevin M.; Dorsey, Zachary; Miller, G. Wade; Brady, Patrick Vane; Mulligan, Conrad; Rayburn, Chris

    2006-06-01

    In the United States, economic growth increasingly requires that greater volumes of freshwater be made available for new users, yet supplies of freshwater are already allocated to existing users. Currently, water for new users is made available through re-allocation of xisting water supplies-for example, by cities purchasing agricultural water rights. Water may also be made available through conservation efforts and, in some locales, through the development of ''new'' water from non-traditional sources such as the oceans, deep aquifer rackish groundwater, and water reuse.

  5. Fundamental Understanding of Crack Growth in Structural Components of Generation IV Supercritical Light Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Iouri I. Balachov; Takao Kobayashi; Francis Tanzella; Indira Jayaweera; Palitha Jayaweera; Petri Kinnunen; Martin Bojinov; Timo Saario

    2004-11-17

    This work contributes to the design of safe and economical Generation-IV Super-Critical Water Reactors (SCWRs) by providing a basis for selecting structural materials to ensure the functionality of in-vessel components during the entire service life. During the second year of the project, we completed electrochemical characterization of the oxide film properties and investigation of crack initiation and propagation for candidate structural materials steels under supercritical conditions. We ranked candidate alloys against their susceptibility to environmentally assisted degradation based on the in situ data measure with an SRI-designed controlled distance electrochemistry (CDE) arrangement. A correlation between measurable oxide film properties and susceptibility of austenitic steels to environmentally assisted degradation was observed experimentally. One of the major practical results of the present work is the experimentally proven ability of the economical CDE technique to supply in situ data for ranking candidate structural materials for Generation-IV SCRs. A potential use of the CDE arrangement developed ar SRI for building in situ sensors monitoring water chemistry in the heat transport circuit of Generation-IV SCWRs was evaluated and proved to be feasible.

  6. A new model for the structure function of integrated water vapor in turbulence

    International Nuclear Information System (INIS)

    Bobak, Justin P.; Ruf, Christopher S.

    1999-01-01

    Turbulent fluctuation of integrated water vapor in the troposphere is one of the major noise sources in radio interferometry. Processed integrated water vapor estimates from microwave radiometers colocated with interferometers have been used to set bounds on this uncertainty. The bound has been in the form of a calculated structure function, which is a measure of temporal or spatial decorrelation of fluctuations. In this paper a new model is presented for the estimation of the structure function in the absence of radiometer measurements. Using this model, the structure function can be estimated using measurements or estimates of a limited number of meteorological parameters. These parameters include boundary layer depth, surface heat and humidity fluxes, entrainment humidity flux, average virtual potential temperature in the boundary layer, and geostrophic wind speed. These parameters can be found or estimated from radiosonde and surface eddy correlation system data. The model is based on a framework of turbulence meteorology and provides excellent agreement when compared with state-of-the-art atmospheric turbulence simulations. Results of preliminary comparisons with ground truth show some excellent agreement, as well as some problems. The performance of the new model exceeds that of one current model. (c) 1999 American Geophysical Union

  7. Structural analysis of surface film on alloy 600 formed under environment of PWR primary water

    Energy Technology Data Exchange (ETDEWEB)

    Terachi, Takumi; Totsuka, Nobuo; Yamada, Takuyo; Nakagawa, Tomokazu [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan); Deguchi, Hiroshi [Kansai Electric Power Co., Inc., Osaka (Japan); Horiuchi, Masaki; Oshitani, Masato [Kanden Kako Co., Ltd., Osaka (Japan)

    2002-09-01

    It has been shown by one of the present authors and so forth that PWSCC of alloy 600 relates to dissolved hydrogen concentration (DH) in water and oxide film structure. However, the mechanism of PWSCC has not been clear yet. Therefore, in order to investigate relationship between them, structural analysis of the oxide film formed under the environment of PWR primary water was carried out by using X-ray diffraction, the scanning electron microscope and the transmission electron microscope. Especially, to perform accurate analysis, the synchrotron orbital radiation with SPring-8 was tried to use for thin film X-ray diffraction measurement. From the results, observed are as follows: 1. the oxide film is mainly composed of NiO, under the condition without hydrogen. 2. In the environment of DH 2.75ppm, the oxide film forms thin spinel structures. 3. On the other hand, needlelike oxides are formed at DH 1ppm. For this reason, around 1ppm of DH there would be the boundary that stable NiO and spinel oxide generate, and it agrees with the peak range of the PWSCC susceptibility on hydrogen. From this, it is suggested that the boundary of NiO/spinel oxide affects the SCC susceptibility. (author)

  8. Forest canopy water fluxes can be estimated using canopy structure metrics derived from airborne light detection and ranging (LiDAR)

    DEFF Research Database (Denmark)

    Schumacher, Johannes; Christiansen, Jesper Riis

    2015-01-01

    Forests contribute to improve water quality, affect drinking water resources, and therefore influence water supply on a regional level. The forest canopy structure affects the retention of precipitation (Pr) in the canopy and hence the amount of water transferred to the forest floor termed canopy...... impacts water resources on a large scale in regions where forests play a major role in water resource management....

  9. Atomic structure of diamond {111} surfaces etched in oxygen water vapor

    International Nuclear Information System (INIS)

    Theije, F.K. de; Reedijk, M.F.; Arsic, J.; Enckevort, W.J.P. van; Vlieg, E.

    2001-01-01

    The atomic structure of the {111} diamond face after oxygen-water-vapor etching is determined using x-ray scattering. We find that a single dangling bond diamond {111} surface model, terminated by a full monolayer of -OH fits our data best. To explain the measurements it is necessary to add an ordered water layer on top of the -OH terminated surface. The vertical contraction of the surface cell and the distance between the oxygen atoms are generally in agreement with model calculations and results on similar systems. The OH termination is likely to be present during etching as well. This model experimentally confirms the atomic-scale mechanism we proposed previously for this etching system

  10. Complex networks from experimental horizontal oil–water flows: Community structure detection versus flow pattern discrimination

    International Nuclear Information System (INIS)

    Gao, Zhong-Ke; Fang, Peng-Cheng; Ding, Mei-Shuang; Yang, Dan; Jin, Ning-De

    2015-01-01

    We propose a complex network-based method to distinguish complex patterns arising from experimental horizontal oil–water two-phase flow. We first use the adaptive optimal kernel time–frequency representation (AOK TFR) to characterize flow pattern behaviors from the energy and frequency point of view. Then, we infer two-phase flow complex networks from experimental measurements and detect the community structures associated with flow patterns. The results suggest that the community detection in two-phase flow complex network allows objectively discriminating complex horizontal oil–water flow patterns, especially for the segregated and dispersed flow patterns, a task that existing method based on AOK TFR fails to work. - Highlights: • We combine time–frequency analysis and complex network to identify flow patterns. • We explore the transitional flow behaviors in terms of betweenness centrality. • Our analysis provides a novel way for recognizing complex flow patterns. • Broader applicability of our method is demonstrated and articulated

  11. Probing ion-specific effects on aqueous acetate solutions: Ion pairing versus water structure modifications

    Directory of Open Access Journals (Sweden)

    Tristan Petit

    2014-05-01

    Full Text Available The effect of monovalent cations (Li+, K+, NH4+, Na+ on the water structure in aqueous chloride and acetate solutions was characterized by oxygen K-edge X-ray absorption spectroscopy (XAS, X-ray emission spectroscopy, and resonant inelastic X-ray scattering (RIXS of a liquid microjet. We show ion- and counterion dependent effects on the emission spectra of the oxygen K-edge, which we attribute to modifications of the hydrogen bond network of water. For acetates, ion pairing with carboxylates was also probed selectively by XAS and RIXS. We correlate our experimental results to speciation data and to the salting-out properties of the cations.

  12. Relating soil microbial activity to water content and tillage-induced differences in soil structure

    DEFF Research Database (Denmark)

    Schjønning, Per; Thomsen, Ingrid Kaag; Petersen, Søren O

    2011-01-01

    Several studies have identified optima in soil water content for aerobic microbial activity, and this has been ascribed to a balance between gas and solute diffusivity as limiting processes. We investigated the role of soil structure, as created by different tillage practices (moldboard ploughing......, MP, or shallow tillage, ST), in regulating net nitrification, applied here as an index of aerobic microbial activity. Intact soil cores were collected at 0–4 and 14–18 cm depth from a fine sandy (SAND) and a loamy (LOAM) soil. The cores were drained to one of seven matric potentials ranging from − 15...... content to a maximum and then decreased. This relationship was modelled with a second order polynomium. Model parameters did not show any tillage effect on the optimum water content, but the optimum coincided with a lower matric potential in ST (SAND: − 140 to –197 hPa; LOAM: − 37 to − 65 hPa) than in MP...

  13. 1st International Conference on Hydraulic Design in Water Resources Engineering : Channels and Channel Control Structures

    CERN Document Server

    1984-01-01

    The development of water resources has proceeded at an amazing speed around the world in the last few decades. The hydraulic engineer has played his part: in constructing much larger artificial channels than ever before, larger and more sophisticated control structures, and systems of irrigation, drainage and water supply channels in which the flow by its nature is complex and unsteady requiring computer-based techniques at both the design and operation stage. It seemed appropriate to look briefly at some of the developments in hydraulic design resulting from this situation. Hence the idea of the Conference was formed. The Proceedings of the Conference show that hydraulic engineers have been able to acquire a very substantial base of design capability from the experience of the period referred to. The most outstanding development to have occurred is in the combination of physical and mathematical modelling, which in hydraulic engineering has followed a parallel path to that in other branches of engineering sc...

  14. The structure of a lipid-water lamellar phase containing two types of lipid monolayers

    International Nuclear Information System (INIS)

    Ranck, J.L.; Luzzati, V.; Zaccai, G.

    1980-01-01

    One lamellar phase, observed in the mitochondrial lipids-water system at low temperature (ca 253 K) and at low water content (ca 15%), contains four lipid monolayers in its unit cell, two of type α and two of type β. Previous X-ray scattering studies of this phase led to an ambiguity: the phase could contain either two homogeneous bilayers, one α and one β, or two mixed bilayers, each formed by an α and a β monolayer. A solution to this problem was sought in a neutron scattering study as a function of the D 2 O/H 2 O ratio. Because of limited resolution, straightforward analysis of the neutron scattering data leads also to ambiguous results. Using a more sophisticated analysis based upon the zeroth- and second-order moments of the Patterson peaks relevant to the exchangeable components, it is shown that the weight of the evidence is in favour of a structure containing mixed bilayers. (Auth.)

  15. Coordination structure of adsorbed Zn(II) at Water-TiO2 interfaces

    Energy Technology Data Exchange (ETDEWEB)

    He, G.; Pan, G.; Zhang, M.; Waychunas, G.A.

    2011-01-15

    The local structure of aqueous metal ions on solid surfaces is central to understanding many chemical and biological processes in soil and aquatic environments. Here, the local coordination structure of hydrated Zn(II) at water-TiO{sub 2} interfaces was identified by extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) spectroscopy combined with density functional theory (DFT) calculations. A nonintegral coordination number of average {approx}4.5 O atoms around a central Zn atom was obtained by EXAFS analysis. DFT calculations indicated that this coordination structure was consistent with the mixture of 4-coordinated bidentate binuclear (BB) and 5-coordinated bidentate mononuclear (BM) metastable equilibrium adsorption (MEA) states. The BB complex has 4-coordinated Zn, while the monodentate mononuclear (MM) complex has 6-coordinated Zn, and a 5-coordinated adsorbed Zn was found in the BM adsorption mode. DFT calculated energies showed that the lower-coordinated BB and BM modes were thermodynamically more favorable than the higher-coordinated MM MEA state. The experimentally observed XANES fingerprinting provided additional direct spectral evidence of 4- and 5-coordinated Zn-O modes. The overall spectral and computational evidence indicated that Zn(II) can occur in 4-, 5-, and 6-oxygen coordinated sites in different MEA states due to steric hindrance effects, and the coexistence of different MEA states formed the multiple coordination environments.

  16. Molecular dynamics simulations of structural transformation of perfluorooctane sulfonate (PFOS) at water/rutile interfaces.

    Science.gov (United States)

    He, Guangzhi; Zhang, Meiyi; Zhou, Qin; Pan, Gang

    2015-09-01

    Concentration and salinity conditions are the dominant environmental factors affecting the behavior of perfluorinated compounds (PFCs) on the surfaces of a variety of solid matrices (suspended particles, sediments, and natural minerals). However, the mechanism has not yet been examined at molecular scales. Here, the structural transformation of perfluorooctane sulfonate (PFOS) at water/rutile interfaces induced by changes of the concentration level of PFOS and salt condition was investigated using molecular dynamics (MD) simulations. At low and intermediate concentrations all PFOS molecules directly interacted with the rutile (110) surface mainly by the sulfonate headgroups through electrostatic attraction, yielding a typical monolayer structure. As the concentration of PFOS increased, the molecules aggregated in a complex multi-layered structure, where an irregular assembling configuration was adsorbed on the monolayer structure by the van der Waals interactions between the perfluoroalkyl chains. When adding CaCl2 to the system, the multi-layered structure changed to a monolayer again, indicating that the addition of CaCl2 enhanced the critical concentration value to yield PFOS multilayer assemblies. The divalent Ca(2+) substituted for monovalent K(+) as the bridging counterion in PFOS adsorption. MD simulation may trigger wide applications in study of perfluorinated compounds (PFCs) from atomic/molecular scale. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Smart nanogels at the air/water interface: structural studies by neutron reflectivity

    Science.gov (United States)

    Zielińska, Katarzyna; Sun, Huihui; Campbell, Richard A.; Zarbakhsh, Ali; Resmini, Marina

    2016-02-01

    The development of effective transdermal drug delivery systems based on nanosized polymers requires a better understanding of the behaviour of such nanomaterials at interfaces. N-Isopropylacrylamide-based nanogels synthesized with different percentages of N,N'-methylenebisacrylamide as cross-linker, ranging from 10 to 30%, were characterized at physiological temperature at the air/water interface, using neutron reflectivity (NR), with isotopic contrast variation, and surface tension measurements; this allowed us to resolve the adsorbed amount and the volume fraction of nanogels at the interface. A large conformational change for the nanogels results in strong deformations at the interface. As the percentage of cross-linker incorporated in the nanogels becomes higher, more rigid matrices are obtained, although less deformed, and the amount of adsorbed nanogels is increased. The data provide the first experimental evidence of structural changes of nanogels as a function of the degree of cross-linking at the air/water interface.The development of effective transdermal drug delivery systems based on nanosized polymers requires a better understanding of the behaviour of such nanomaterials at interfaces. N-Isopropylacrylamide-based nanogels synthesized with different percentages of N,N'-methylenebisacrylamide as cross-linker, ranging from 10 to 30%, were characterized at physiological temperature at the air/water interface, using neutron reflectivity (NR), with isotopic contrast variation, and surface tension measurements; this allowed us to resolve the adsorbed amount and the volume fraction of nanogels at the interface. A large conformational change for the nanogels results in strong deformations at the interface. As the percentage of cross-linker incorporated in the nanogels becomes higher, more rigid matrices are obtained, although less deformed, and the amount of adsorbed nanogels is increased. The data provide the first experimental evidence of structural changes

  18. Diversity and structure of Chironomidae communities in relation to water quality differences in the Swartkops River

    Science.gov (United States)

    Odume, O. N.; Muller, W. J.

    The Swartkops River is an important freshwater ecosystem in South Africa. But owing to its location, it suffers varying degrees of human induced impacts which include industrial and domestic effluent discharges, deforestation as well as agricultural land use which have negatively impacted on the water quality. Diversity and community composition of aquatic insects are frequently used to assess environmental water quality status. Chironomids occupy extremely varied biotopes. Their extraordinary ecological range and environmental sensitivity make them particularly useful for assessing and interpreting changes in water quality of aquatic ecosystems. The community structure of chironomid larvae was investigated at four sites in the Swartkops River and effects of different chemical and physical variables on their distribution were explored. Chironomid larvae were collected using the South African Scoring System version 5 (SASS5) protocol. A total of 26 taxa from four sampling sites in the Swartkops River were identified. Margalef’s species richness index, equitability, Shannon and Simpson diversity indices were highest at site 1 (reference site). The downstream sites contained 6-20 taxa compared to the 25 taxa at site 1. Site 1 was characterised by the subfamilies Orthocladiinae, Tanypodinae and the tribe Tanytarsini while the impacted sites were characterised by Orthocladiinae and Chironomini. Chironomus spp., Dirotendipes sp., Kiefferulus sp. and Tanypus sp. seemed to be tolerant to pollution, occurring in high abundance at sites 2, 3 and 4. In contrast, Polypedilum sp., Tanytarsus sp., Orthocladius sp., Cricotopus spp. and Ablabesmyia sp. appeared to be more sensitive taxa, being less common at the impacted sites (sites 2, 3 and 4). Five days biochemical oxygen demand, dissolved oxygen, electrical conductivity, orthophosphate-phosphorus and total inorganic nitrogen were among the important variables that determine the observed chironomid community structure

  19. New era / new solutions: The role of alternative tariff structures in water supply projects.

    Science.gov (United States)

    Pinto, F Silva; Marques, R Cunha

    2017-12-01

    Water utilities face different challenges that may force them to seek prioritized objectives. When doing so, particular projects may have to be developed, being important to understand their impact on water tariffs, and thus, on customers. Such consequences may bear an increased relevance in cases stressed with, e.g., resource scarcity, poverty, and the need for infrastructure investments. The resulting cost and revenue variability demand a comprehensive study. If the first may require a stochastic modeling (in major cost components) in order to consider its inherent uncertainty, the second needs to be modeled following context-specific objectives set by the relevant stakeholders. The solutions achieved will likely promote distinct revenue sources, as well as diversified water tariff structures. A multi-objective optimization model (i.e., a Framework for Suitable Prices) is built to deal with those diversified requirements (e.g., stochastic energy costs, affordability, cost recovery, or administrative simplicity). The model is solved through achievement scalarizing functions with several weighting coefficients for a reference point, so as to provide a significant perception of possible revenue options (and their impact) to the decision makers. The proposed method is applied to a case study, Boa Vista Island in Cabo Verde, in which the background characteristics, namely water sources availability (e.g., the adoption of desalination technologies), economic development and other contextual factors were considered. The key role of tariff structure selection is displayed, instead of assuming it a priori, giving important insights regarding project feasibility. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. A surprisingly simple correlation between the classical and quantum structural networks in liquid water

    Science.gov (United States)

    Hamm, Peter; Fanourgakis, George S.; Xantheas, Sotiris S.

    2017-08-01

    Nuclear quantum effects in liquid water have profound implications for several of its macroscopic properties related to the structure, dynamics, spectroscopy, and transport. Although several of water's macroscopic properties can be reproduced by classical descriptions of the nuclei using interaction potentials effectively parameterized for a narrow range of its phase diagram, a proper account of the nuclear quantum effects is required to ensure that the underlying molecular interactions are transferable across a wide temperature range covering different regions of that diagram. When performing an analysis of the hydrogen-bonded structural networks in liquid water resulting from the classical (class) and quantum (qm) descriptions of the nuclei with two interaction potentials that are at the two opposite ends of the range in describing quantum effects, namely the flexible, pair-wise additive q-TIP4P/F, and the flexible, polarizable TTM3-F, we found that the (class) and (qm) results can be superimposed over the temperature range T = 250-350 K using a surprisingly simple, linear scaling of the two temperatures according to T(qm) = α T(class) + ΔT, where α = 0.99 and ΔT = -6 K for q-TIP4P/F and α = 1.24 and ΔT = -64 K for TTM3-F. This simple relationship suggests that the structural networks resulting from the quantum and classical treatment of the nuclei with those two very different interaction potentials are essentially similar to each other over this extended temperature range once a model-dependent linear temperature scaling law is applied.

  1. The interplay between dynamic heterogeneities and structure of bulk liquid water: A molecular dynamics simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Demontis, Pierfranco; Suffritti, Giuseppe B. [Dipartimento di Chimica e Farmacia, Università degli studi di Sassari, Sassari (Italy); Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM), Unità di ricerca di Sassari, Via Vienna, 2, I-07100 Sassari (Italy); Gulín-González, Jorge [Grupo de Matemática y Física Computacionales, Universidad de las Ciencias Informáticas (UCI), Carretera a San Antonio de los Baños, Km 21/2, La Lisa, La Habana (Cuba); Masia, Marco [Dipartimento di Chimica e Farmacia, Università degli studi di Sassari, Sassari (Italy); Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM), Unità di ricerca di Sassari, Via Vienna, 2, I-07100 Sassari (Italy); Istituto Officina dei Materiali del CNR, UOS SLACS, Via Vienna 2, 07100 Sassari (Italy); Sant, Marco [Dipartimento di Chimica e Farmacia, Università degli studi di Sassari, Sassari (Italy)

    2015-06-28

    In order to study the interplay between dynamical heterogeneities and structural properties of bulk liquid water in the temperature range 130–350 K, thus including the supercooled regime, we use the explicit trend of the distribution functions of some molecular properties, namely, the rotational relaxation constants, the atomic mean-square displacements, the relaxation of the cross correlation functions between the linear and squared displacements of H and O atoms of each molecule, the tetrahedral order parameter q and, finally, the number of nearest neighbors (NNs) and of hydrogen bonds (HBs) per molecule. Two different potentials are considered: TIP4P-Ew and a model developed in this laboratory for the study of nanoconfined water. The results are similar for the dynamical properties, but are markedly different for the structural characteristics. In particular, for temperatures higher than that of the dynamic crossover between “fragile” (at higher temperatures) and “strong” (at lower temperatures) liquid behaviors detected around 207 K, the rotational relaxation of supercooled water appears to be remarkably homogeneous. However, the structural parameters (number of NNs and of HBs, as well as q) do not show homogeneous distributions, and these distributions are different for the two water models. Another dynamic crossover between “fragile” (at lower temperatures) and “strong” (at higher temperatures) liquid behaviors, corresponding to the one found experimentally at T{sup ∗} ∼ 315 ± 5 K, was spotted at T{sup ∗} ∼ 283 K and T{sup ∗} ∼ 276 K for the TIP4P-Ew and the model developed in this laboratory, respectively. It was detected from the trend of Arrhenius plots of dynamic quantities and from the onset of a further heterogeneity in the rotational relaxation. To our best knowledge, it is the first time that this dynamical crossover is detected in computer simulations of bulk water. On the basis of the simulation results, the possible

  2. Effects of some structural materials on the reactivity and flux distributions in a pressurised water reactor

    International Nuclear Information System (INIS)

    Mondal, A.M.W.; Mannan, M.A.

    1983-01-01

    The effect of the structural materials of the guide tubes, spacer grids and the shroud on the reactivity and the flux distribution of a Pressurised Water Reactor (PWR) has been studied. Group constants of different cells of guide tubes, spacer grids, shroud and the fuel have been calculated using the cell codes LEOPARD, PANTHER and METHUSELAH. Core calculations have been performed using the diffusion code EQUIPOISE. It has been found for a PWR of 1300 MWe of Kraftwork Union design for Iron that the total change in reactivity due to the presence of guide tubes, spacer grids and the shroud is about -2.48x10 -2 . (author)

  3. On the influence of molecular structure on the conductivity of electrolyte solutions - sodium nitrate in water

    Directory of Open Access Journals (Sweden)

    H. Krienke

    2013-01-01

    Full Text Available Theoretical calculations of the conductivity of sodium nitrate in water are presented and compared with experimental measurements. The method of direct correlation force in the framework of the interionic theory is used for the calculation of transport properties in connection with the associative mean spherical approximation (AMSA. The effective interactions between ions in solutions are derived with the help of Monte Carlo and Molecular Dynamics calculations on the Born-Oppenheimer level. This work is based on earlier theoretical and experimental studies of the structure of concentrated aqueous sodium nitrate solutions.

  4. Structural elements of collapses in shallow water flows with horizontally nonuniform density

    Energy Technology Data Exchange (ETDEWEB)

    Goncharov, V. P., E-mail: v.goncharov@rambler.ru [Russian Academy of Sciences, Obukhov Institute of Atmospheric Physics (Russian Federation); Pavlov, V. I., E-mail: Vadim.Pavlov@univ-lille1.fr [Universite de Lille 1, UFR de Mathematiques Pures et Appliquees-LML UMR 8107 (France)

    2013-10-15

    The mechanisms and structural elements of instability whose evolution results in the occurrence of the collapse are studied in the scope of the rotating shallow water model with a horizontally nonuniform density. The diagram stability based on the integral collapse criterion is suggested to explain system behavior in the space of constants of motion. Analysis of the instability shows that two collapse scenarios are possible. One scenario implies anisotropic collapse during which the contact area of a collapsing drop-like fragment with the bottom contracts into a rotating segment. The other implies isotropic contraction of the area into a point.

  5. Visualizing Vpr-induced G2 arrest and apoptosis.

    Directory of Open Access Journals (Sweden)

    Tomoyuki Murakami

    Full Text Available Vpr is an accessory protein of human immunodeficiency virus type 1 (HIV-1 with multiple functions. The induction of G2 arrest by Vpr plays a particularly important role in efficient viral replication because the transcriptional activity of the HIV-1 long terminal repeat is most active in G2 phase. The regulation of apoptosis by Vpr is also important for immune suppression and pathogenesis during HIV infection. However, it is not known whether Vpr-induced apoptosis depends on the ability of Vpr to induce G2 arrest, and the dynamics of Vpr-induced G2 arrest and apoptosis have not been visualized. We performed time-lapse imaging to examine the temporal relationship between Vpr-induced G2 arrest and apoptosis using HeLa cells containing the fluorescent ubiquitination-based cell cycle indicator2 (Fucci2. The dynamics of G2 arrest and subsequent long-term mitotic cell rounding in cells transfected with the Vpr-expression vector were visualized. These cells underwent nuclear mis-segregation after prolonged mitotic processes and then entered G1 phase. Some cells subsequently displayed evidence of apoptosis after prolonged mitotic processes and nuclear mis-segregation. Interestingly, Vpr-induced apoptosis was seldom observed in S or G2 phase. Likewise, visualization of synchronized HeLa/Fucci2 cells infected with an adenoviral vector expressing Vpr clearly showed that Vpr arrests the cell cycle at G2 phase, but does not induce apoptosis at S or G2 phase. Furthermore, time-lapse imaging of HeLa/Fucci2 cells expressing SCAT3.1, a caspase-3-sensitive fusion protein, clearly demonstrated that Vpr induces caspase-3-dependent apoptosis. Finally, to examine whether the effects of Vpr on G2 arrest and apoptosis were reversible, we performed live-cell imaging of a destabilizing domain fusion Vpr, which enabled rapid stabilization and destabilization by Shield1. The effects of Vpr on G2 arrest and subsequent apoptosis were reversible. This study is the first to

  6. Simultaneous improvement in productivity, water use, and albedo through crop structural modification.

    Science.gov (United States)

    Drewry, Darren T; Kumar, Praveen; Long, Stephen P

    2014-06-01

    Spanning 15% of the global ice-free terrestrial surface, agricultural lands provide an immense and near-term opportunity to address climate change, food, and water security challenges. Through the computationally informed breeding of canopy structural traits away from those of modern cultivars, we show that solutions exist that increase productivity and water use efficiency, while increasing land-surface reflectivity to offset greenhouse gas warming. Plants have evolved to maximize capture of radiation in the upper leaves, thus shading competitors. While important for survival in the wild, this is suboptimal in monoculture crop fields for maximizing productivity and other biogeophysical services. Crop progenitors evolved over the last 25 million years in an atmosphere with less than half the [CO2] projected for 2050. By altering leaf photosynthetic rates, rising [CO2] and temperature may also alter the optimal canopy form. Here using soybean, the world's most important protein crop, as an example we show by applying optimization routines to a micrometeorological leaf canopy model linked to a steady-state model of photosynthesis, that significant gains in production, water use, and reflectivity are possible with no additional demand on resources. By modifying total canopy leaf area, its vertical profile and angular distribution, and shortwave radiation reflectivity, all traits available in most major crop germplasm collections, increases in productivity (7%) are possible with no change in water use or albedo. Alternatively, improvements in water use (13%) or albedo (34%) can likewise be made with no loss of productivity, under Corn Belt climate conditions. © 2014 California Institute of Technology. Government sponsorship acknowledged.

  7. Instability Mechanisms of Water-in-Oil Nanoemulsions with Phospholipids: Temporal and Morphological Structures.

    Science.gov (United States)

    Sommerling, Jan-Hendrik; de Matos, Maria B C; Hildebrandt, Ellen; Dessy, Alberto; Kok, Robbert Jan; Nirschl, Hermann; Leneweit, Gero

    2018-01-16

    Many food preparations, pharmaceuticals, and cosmetics use water-in-oil (W/O) emulsions stabilized by phospholipids. Moreover, recent technological developments try to produce liposomes or lipid coated capsules from W/O emulsions, but are faced with colloidal instabilities. To explore these instability mechanisms, emulsification by sonication was applied in three cycles, and the sample stability was studied for 3 h after each cycle. Clearly identifiable temporal structures of instability provide evidence about the emulsion morphology: an initial regime of about 10 min is shown to be governed by coalescence after which Ostwald ripening dominates. Transport via molecular diffusion in Ostwald ripening is commonly based on the mutual solubility of the two phases and is therefore prohibited in emulsions composed of immiscible phases. However, in the case of water in oil emulsified by phospholipids, these form water-loaded reverse micelles in oil, which enable Ostwald ripening despite the low solubility of water in oil, as is shown for squalene. As is proved for the phospholipid dipalmitoylphosphatidylcholine (DPPC), concentrations below the critical aggregation concentration (CAC) form monolayers at the interfaces and smaller droplet sizes. In contrast, phospholipid concentrations above the CAC create complex multilayers at the interface with larger droplet sizes. The key factors for stable W/O emulsions in classical or innovative applications are first, the minimization of the phospholipids' capacity to form reversed micelles, and second, the adaption of the initial phospholipid concentration to the water content to enable an optimized coverage of phospholipids at the interfaces for the intended drop size.

  8. Corrosion resistance of structural material AlMg-2 in water following heat treatment and cooling

    International Nuclear Information System (INIS)

    Maman Kartaman A; Djoko Kisworo; Dedi Hariyadi; Sigit

    2005-01-01

    Corrosion tests of structural material AlMg-2 in water were carried out using autoclave in order to study the effects of heat treatment on the corrosion resistance of the material. Prior to the tests, the samples were heat-treated at temperatures of 90, 200, 300 and 500 °C and cooled in air, sand and water. The corrosion tests were conducted in water at temperature of 150 °C for 250 hours. The results showed that AlMg-2 samples were corroded although the increase of mass gain was relatively small. Heat treatment from 90 to 500 °C in sand cooling media resulted in an increase of mass gain despite that at 300 °C the increase was less than those at 200 °C and 500 °C. For water cooling media in the temperature range of 90 to 200 °C, the mass gain increased from 0.1854 g/cm 2 to 2.1204 g/cm 2 although after 200 °C it decreased to 1.8207 g/cm 2 and 1.6779 g/cm 2 respectively. For air cooling media, the mass gain was relatively constant. Based on the experiment results, it can be concluded that heat treatment and cooling did not significantly influence the corrosion resistance of material AlMg-2. The passive film Al 2 O 3 on the surface was able to protect the inner surface from further corrosion. Water media with pH range from 4 – 9 did not cause damage to passive layer formed. (author)

  9. Serum tau and neurological outcome in cardiac arrest

    DEFF Research Database (Denmark)

    Mattsson, Niklas; Zetterberg, Henrik; Nielsen, Niklas

    2017-01-01

    OBJECTIVE: To test serum tau as a predictor of neurological outcome after cardiac arrest. METHODS: We measured the neuronal protein tau in serum at 24, 48, and 72 hours after cardiac arrest in 689 patients in the prospective international Target Temperature Management trial. The main outcome...... was poor neurological outcome, defined as Cerebral Performance Categories 3-5 at 6 months. RESULTS: Increased tau was associated with poor outcome at 6 months after cardiac arrest (median = 38.5, interquartile range [IQR] = 5.7-245ng/l in poor vs median = 1.5, IQR = 0.7-2.4ng/l in good outcome, for tau....... The accuracy in predicting outcome by serum tau was equally high for patients randomized to 33 °C and 36 °C targeted temperature after cardiac arrest. INTERPRETATION: Serum tau is a promising novel biomarker for prediction of neurological outcome in patients with cardiac arrest. It may be significantly better...

  10. Major life events as potential triggers of sudden cardiac arrest.

    Science.gov (United States)

    Wicks, April F; Lumley, Thomas; Lemaitre, Rozenn N; Sotoodehnia, Nona; Rea, Thomas D; McKnight, Barbara; Strogatz, David S; Bovbjerg, Viktor E; Siscovick, David S

    2012-05-01

    We investigated the risk of sudden cardiac arrest in association with the recent loss of, or separation from, a family member or friend. Our case-crossover study included 490 apparently healthy married residents of King County, Washington, who suffered sudden cardiac arrest between 1988 and 2005. We compared exposure to spouse-reported family/friend events occurring ≤ 1 month before sudden cardiac arrest with events occurring in the previous 5 months. We evaluated potential effect modification by habitual vigorous physical activity. Recent family/friend events were associated with a higher risk of sudden cardiac arrest (odds ratio [OR] = 1.6; 95% confidence interval [CI] = 1.1-2.4). ORs for cases with and without habitual vigorous physical activity were 1.1 (0.6-2.2) and 2.0 (1.2-3.1), respectively (interaction P = 0.02). These results suggest family/friend events may trigger sudden cardiac arrest and raise the hypothesis that habitual vigorous physical activity may lower susceptibility to these potential triggers.

  11. Current Pharmacological Advances in the Treatment of Cardiac Arrest

    Directory of Open Access Journals (Sweden)

    Andry Papastylianou

    2012-01-01

    Full Text Available Cardiac arrest is defined as the sudden cessation of spontaneous ventilation and circulation. Within 15 seconds of cardiac arrest, the patient loses consciousness, electroencephalogram becomes flat after 30 seconds, pupils dilate fully after 60 seconds, and cerebral damage takes place within 90–300 seconds. It is essential to act immediately as irreversible damage can occur in a short time. Cardiopulmonary resuscitation (CPR is an attempt to restore spontaneous circulation through a broad range of interventions which are early defibrillation, high-quality and uninterrupted chest compressions, advanced airway interventions, and pharmacological interventions. Drugs should be considered only after initial shocks have been delivered (when indicated and chest compressions and ventilation have been started. During cardiopulmonary resuscitation, no specific drug therapy has been shown to improve survival to hospital discharge after cardiac arrest, and only few drugs have a proven benefit for short-term survival. This paper reviews current pharmacological treatment of cardiac arrest. There are three groups of drugs relevant to the management of cardiac arrest: vasopressors, antiarrhythmics, and other drugs such as sodium bicarbonate, calcium, magnesium, atropine, fibrinolytic drugs, and corticosteroids.

  12. The effectiveness of silver diamine fluoride in arresting caries.

    Science.gov (United States)

    Richards, Derek

    2017-10-27

    Data sourcesPubMed, Embase, Scopus, China National Knowledge Infrastructure (CNKI), Ichushi-web, Biblioteca Virtual en Salud Espana (BVSE) and Biblioteca Virtual em Saude (BVS) databases. There were no limits on language or publication dates.Study selectionTwo reviewers selected prospective clinical studies investigating SDF treatment for caries prevention in children.Data extraction and synthesisData was abstracted independently by two reviewers and risk of bias assessed. Meta-analysis was performed on studies in which the caries-arresting rate using 38% SDF solution on primary teeth could be obtained or calculated.ResultsNineteen studies were included; 16 were conducted in the primary dentition and three in permanent dentition. Fourteen studies used 38% SDF, three 30% SDF, and two 10% SDF. Eight studies using 38% SDF contributed to a meta-analysis and the overall proportion of arrested caries was 81% (95% CI; 68-89%). Percentage reductions were also calculated for 6,12,18,24 and >30 months. Arrested carious lesions stained black but no other adverse effects were reported.ConclusionsSDF commonly used at a high concentration (38%, 44,800ppm fluoride) is effective in arresting caries among children. There is no consensus on its number and frequency of application to arrest caries. Further studies are necessary to develop evidence-based guidelines on its use in children.

  13. Systematic comparison of crystalline and amorphous phases: Charting the landscape of water structures and transformations

    International Nuclear Information System (INIS)

    Pietrucci, Fabio; Martoňák, Roman

    2015-01-01

    Systematically resolving different crystalline phases starting from the atomic positions, a mandatory step in algorithms for the prediction of structures or for the simulation of phase transitions, can be a non-trivial task. Extending to amorphous phases and liquids which lack the discrete symmetries, the problem becomes even more difficult, involving subtle topological differences at medium range that, however, are crucial to the physico-chemical and spectroscopic properties of the corresponding materials. Typically, system-tailored order parameters are devised, like global or local symmetry indicators, ring populations, etc. We show that a recently introduced metric provides a simple and general solution to this intricate problem. In particular, we demonstrate that a map can be traced displaying distances among water phases, including crystalline as well as amorphous states and the liquid, consistently with experimental knowledge in terms of phase diagram, structural features, and preparation routes

  14. Light water reactor fuel analysis code FEMAXI-IV(Ver.2). Detailed structure and user's manual

    International Nuclear Information System (INIS)

    Suzuki, Motoe; Saitou, Hiroaki.

    1997-11-01

    A light water reactor fuel behavior analysis code FEMAXI-IV(Ver.2) was developed as an improved version of FEMAXI-IV. Development of FEMAXI-IV has been already finished in 1992, though a detailed structure and input manual of the code have not been open to users yet. Here, the basic theories and structure, the models and numerical solutions applied to FEMAXI-IV(Ver.2), and the material properties adopted in the code are described in detail. In FEMAXI-IV(Ver.2), programming bugs in previous FEMAXI-IV were eliminated, renewal of the pellet thermal conductivity was performed, and a model of thermal-stress restraint on FP gas release was incorporated. For facilitation of effective and wide-ranging application of the code, methods of input/output of the code are also described in detail, and sample output is included. (author)

  15. Flow structure of conical distributed multiple gas jets injected into a water chamber

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Jiajun; Yu, Yonggang [Nanjing University of Science and Technology, Nanjing (China)

    2017-04-15

    Based on an underwater gun firing project, a mock bullet with several holes on the head was designed and experimented to observe the combustion gas injected into a cylindrical water chamber through this mock bullet. The combustion gas jets contain one vertical central jet and 4 to 8 slant lateral jets. A high speed camera system was used to record the expansion of gas jets in the experimental study. In numerical simulations, the Euler two-fluid model and volume of fluid method were adopted to describe the gas-liquid flow. The results show the backflow zone in lateral jet is the main factor influencing the gas-liquid turbulent mixing in downstream. On cross sections, the gas volume fraction increased with time but the growth rate decreased. With a change of nozzle structure, the gas fraction was more affected than the shock structure.

  16. Standard Test Method for Water Absorption of Core Materials for Structural Sandwich Constructions

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2001-01-01

    1.1 This test method covers the determination of the relative amount of water absorption by various types of structural core materials when immersed or in a high relative humidity environment. This test method is intended to apply to only structural core materials; honeycomb, foam, and balsa wood. 1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given may be approximate. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  17. Structural dynamics of supercooled water from quasielastic neutron scattering and molecular simulations.

    Science.gov (United States)

    Qvist, Johan; Schober, Helmut; Halle, Bertil

    2011-04-14

    One of the outstanding challenges presented by liquid water is to understand how molecules can move on a picosecond time scale despite being incorporated in a three-dimensional network of relatively strong H-bonds. This challenge is exacerbated in the supercooled state, where the dramatic slowing down of structural dynamics is reminiscent of the, equally poorly understood, generic behavior of liquids near the glass transition temperature. By probing single-molecule dynamics on a wide range of time and length scales, quasielastic neutron scattering (QENS) can potentially reveal the mechanistic details of water's structural dynamics, but because of interpretational ambiguities this potential has not been fully realized. To resolve these issues, we present here an extensive set of high-quality QENS data from water in the range 253-293 K and a corresponding set of molecular dynamics (MD) simulations to facilitate and validate the interpretation. Using a model-free approach, we analyze the QENS data in terms of two motional components. Based on the dynamical clustering observed in MD trajectories, we identify these components with two distinct types of structural dynamics: picosecond local (L) structural fluctuations within dynamical basins and slower interbasin jumps (J). The Q-dependence of the dominant QENS component, associated with J dynamics, can be quantitatively rationalized with a continuous-time random walk (CTRW) model with an apparent jump length that depends on low-order moments of the jump length and waiting time distributions. Using a simple coarse-graining algorithm to quantitatively identify dynamical basins, we map the newtonian MD trajectory on a CTRW trajectory, from which the jump length and waiting time distributions are computed. The jump length distribution is gaussian and the rms jump length increases from 1.5 to 1.9 Å as the temperature increases from 253 to 293 K. The rms basin radius increases from 0.71 to 0.75 Å over the same range. The

  18. Pattern of perioperative cardiac arrests at University of Maiduguri Teaching Hospital.

    Science.gov (United States)

    Kwari, Y D; Bello, M R; Eni, U E

    2010-01-01

    Perioperative cardiac arrests and death on the table represent the most serious complications of surgery and anaesthesia. This paper was designed to study their pattern, causes and outcomes following cardiopulmonary resuscitation (CPR) and intensive care unit (ICU) management in our institution. Three year retrospective review of perioperative cardiac arrests and death on operating table following surgical procedure under anaesthesia. For each cardiac arrest or death on the table the sequence of events leading to the arrest was evaluated using case notes, anaesthetic chart and ICU records. Study variables which include demographic data, ASA score, anaesthetic technique, causes and outcome were analysed and discussed. Fourteen perioperative cardiac arrests were encountered following 4051 anaesthetics administered over the three year study period. Twelve out of the fourteen cardiac arrests occurred following general anaesthesia, while the remaining two occurred following spinal anaesthesia. There was no cardiac arrest following local anaesthesia. Children suffered more cardiac arrest than adults. ASA class III and IV risk status suffered more arrests than ASA I and II. Hypoxia from airway problems was the commonest cause of cardiac arrest followed by septic shock. Monitoring with pulse oximeter was done in only 4 out of the 14 cardiac arrests. Only 2 (14%) out of 14 cardiac arrests recovered to home discharge, one of them with significant neurological deficit. Majority of arrests were due to hypoxia from airway problems that were not detected early There is need to improve on patient monitoring, knowledge of CPR and intensive care so as to improve the outcome of perioperative cardiac arrest.

  19. Multi-scale experimental and numerical study of the structure and the dynamics of water confined in clay minerals

    International Nuclear Information System (INIS)

    Guillaud, Emmanuel Bertrand

    2017-01-01

    Clay are complex minerals with a multi-scale porosity and a remarkable ability to swell under humid atmosphere. These materials have many applications in catalysis, waste management, construction industry... However, the properties of confined water are still not fully understood, due in particular to the complexity of water itself. The aim of this work is, using mainly molecular simulations and vibrational spectroscopy, to understand the structure and the dynamics of water confined in clay minerals. To evaluate the accuracy of numerical models to describe water confined in clay minerals, and to understand the origin of its structural and dynamical properties, a large part of the work was devoted to the building blocks of clays: pure bulk water, water at the surface of a solid, and salt water. To this extent, the viscoelastic properties of water from the deeply supercooled regime to the boiling temperature were investigated using classical molecular dynamics. The evolution of the friction properties of water on a prototypical solid surface was also analyzed, and the accuracy of ab initio approaches and empirical salt models was studied. In a second part, those results were confronted to the properties of water confined in clay minerals at low and room temperature, studied both experimentally and numerically. Experimental work consisted mostly in extensive far- and -mid infrared absorption spectrometry measurements, whereas numerical work mainly consisted in empirical molecular dynamics simulations. Especially, the existence of confinement- or temperature-induced phase transitions of confined water was investigated. (author)

  20. Efficiency of temporary storage of geothermal waters in a lake system: Monitoring the changes of water quality and bacterial community structures.

    Science.gov (United States)

    Szirányi, Barbara; Krett, Gergely; Kosáros, Tünde; Janurik, Endre; Pekár, Ferenc; Márialigeti, Károly; Borsodi, Andrea K

    2017-12-01

    Disposal of used geothermal waters in Hungary often means temporary storage in reservoir lakes to reduce temperature and improve water quality. In this study, the physical and chemical properties and changes in the bacterial community structure of a reservoir lake system in southeast region of Hungary were monitored and compared through 2 years, respectively. The values of biological oxygen demand, concentrations of ammonium ion, total inorganic nitrogen, total phosphorous, and total phenol decreased, whereas oxygen saturation, total organic nitrogen, pH, and conductivity increased during the storage period. Bacterial community structure of water and sediment samples was compared by denaturing gradient gel electrophoresis (DGGE) following the amplification of the 16S rRNA gene. According to the DGGE patterns, greater seasonal than spatial differences of bacterial communities were revealed in both water and sediment of the lakes. Representatives of the genera Arthrospira and Anabaenopsis (cyanobacteria) were identified as permanent and dominant members of the bacterial communities.

  1. Strong cooperative effect of oppositely charged surfactant mixtures on their adsorption and packing at the air-water interface and interfacial water structure.

    Science.gov (United States)

    Nguyen, Khoi T; Nguyen, Tuan D; Nguyen, Anh V

    2014-06-24

    Remarkable adsorption enhancement and packing of dilute mixtures of water-soluble oppositely-charged surfactants, sodium dodecyl sulfate (SDS) and dodecyl amine hydrochloride (DAH), at the air-water interface were observed by using sum frequency generation spectroscopy and tensiometry. The interfacial water structure was also observed to be significantly influenced by the SDS-DAH mixtures, differently from the synergy of the single surfactants. Most strikingly, the obtained spectroscopic evidence suggests that the interfacial hydrophobic alkyl chains of the binary mixtures assemble differently from those of single surfactants. This study highlights the significance of the cooperative interaction between the headgroups of oppositely charged binary surfactant systems and subsequently provides some insightful observations about the molecular structure of the air-aqueous interfacial water molecules and, more importantly, about the packing nature of the surfactant hydrophobic chains of dilute SDS-DAH mixtures of concentration below 1% of the CMC.

  2. Wetted-region structure in horizontal unsaturated fractures: Water entry through the surrounding porous matrix

    International Nuclear Information System (INIS)

    Glass, R.J.; Norton, D.L.

    1991-01-01

    Small-scale processes that influence wetted structure within the plane of a horizontal fracture as the fracture wets or drains through the matrix are investigated. Our approach integrates both aperture-scale modeling and physical experimentation. Several types of aperture-scale models have been defined and implemented. A series of physical experimental systems that allow us to measure wetted-region structure as a function of system parameters and water pressure head in analogue fractures also have been designed. In our preliminary proof-of-concept experiment, hysteresis is clearly evident in the measured saturation/pressure relation, as is the process of air entrapment, which causes a reduction in the connected areas between blocks and the wetted region available for flow in the plane of the fracture. A percolation threshold where the system is quickly spanned, allowing fluid conduction in the fracture plane, is observed which is analogous to that found in the aperture-scale models. A fractal wetted and entrapped-region structure is suggested by both experiment and modeling. This structure implies that flow tortuosity for both flow in the fracture and for inter-block fluid transfer is a scale-dependent function of pressure head

  3. OECD - HRP Summer School on Light Water Reactor Structural Materials. August 26th - 30th, 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    In cooperation with the OECD Nuclear Energy Agency (NEA), the Halden Reactor Project organised a Summer School on Light Water Reactor Structural Materials in the period August 26 - 30, 2002. The summer school was primarily intended for people who wanted to become acquainted with materials-related subjects and issues without being experts. It is especially hoped that the summer school served to transfer knowledge to the ''young generation'' in the field of nuclear. Experts from Halden Project member organisations were solicited for the following programme: (1) Overview of The Nuclear Community and Current Issues, (2) Regulatory Framework for Ensuring Structural Integrity, (3) Non-Destructive Testing for Detection of Cracks, (4) Part I - Basics of Radiation and Radiation Damage, (5) Part II - Radiation Effects on Reactor Internal Materials, (6) Water Chemistry and Radiolysis Effects in LWRs, (7) PWR and Fast Breeder Reactor Internals, (8) PWR and Fast Breeder Reactor Internals, (9) Secondary Side Corrosion Cracking of PWR Steam Generator Tubes, (10) BWR Materials and Their Interaction with the Environment, (11) Radiation Damage in Reactor Pressure Vessels.

  4. The Influence of Fluorination on Structure of the Trifluoroacetonitrile Water Complex

    Science.gov (United States)

    Lin, Wei; Wu, Anan; Lu, Xin; Obenchain, Daniel A.; Novick, Stewart E.

    2015-06-01

    Acetonitrile, CH_3CN, and trifluoroacetonitrile, CF_3CN, are symmetric tops. In a recent study of the rotational spectrum of the acetonitrile and water complex, it was observed that the structure was also an effective symmetric top, with the external hydrogen freely rotating about the O-H bond aligned towards the nitrogen of the cyanide of CH_3CN. Unlike the CH_3CN-H_2O complex, the CH_3CN-Ar and CF_3CN-Ar complexes were observed to be asymmetric tops. Having a series of symmetric and asymmetric top complexes of acetonitrile and trifluoracetonitrile for comparison, we report the rotational spectrum of the weakly bound complex between trifluoroacetonitrile and water. Rotational constants and quadrupole coupling constants will be presented, and the structure of CF_3CN-H_2O will be revealed. Lovas, F.J.; Sobhanadri, J. Microwave rotational spectral study of CH_3CN-H_2O and Ar-CH_3CN. J. Mol. Spetrosc. 2015, 307, 59-64. SPOILER ALERT: It's an asymmetric top.

  5. OECD - HRP Summer School on Light Water Reactor Structural Materials. August 26th - 30th, 2002

    International Nuclear Information System (INIS)

    2002-01-01

    In cooperation with the OECD Nuclear Energy Agency (NEA), the Halden Reactor Project organised a Summer School on Light Water Reactor Structural Materials in the period August 26 - 30, 2002. The summer school was primarily intended for people who wanted to become acquainted with materials-related subjects and issues without being experts. It is especially hoped that the summer school served to transfer knowledge to the ''young generation'' in the field of nuclear. Experts from Halden Project member organisations were solicited for the following programme: (1) Overview of The Nuclear Community and Current Issues, (2) Regulatory Framework for Ensuring Structural Integrity, (3) Non-Destructive Testing for Detection of Cracks, (4) Part I - Basics of Radiation and Radiation Damage, (5) Part II - Radiation Effects on Reactor Internal Materials, (6) Water Chemistry and Radiolysis Effects in LWRs, (7) PWR and Fast Breeder Reactor Internals, (8) PWR and Fast Breeder Reactor Internals, (9) Secondary Side Corrosion Cracking of PWR Steam Generator Tubes, (10) BWR Materials and Their Interaction with the Environment, (11) Radiation Damage in Reactor Pressure Vessels

  6. Communication: Relationship between local structure and the stability of water in hydrophobic confinement

    Science.gov (United States)

    Altabet, Y. Elia; Debenedetti, Pablo G.

    2017-12-01

    Liquid water confined between nanoscale hydrophobic objects can become metastable with respect to its vapor at nanoscale separations. While the separations are only several molecular diameters, macroscopic theories are often invoked to interpret the thermodynamics and kinetics of water under confinement. We perform detailed rate and free energy calculations via molecular simulations in order to assess the dependence of the rate of evaporation, free energy barriers, and free energy differences between confined liquid and vapor upon object separation and compare them to the relevant macroscopic theories. At small enough separations, the rate of evaporation appears to deviate significantly from the predictions of classical nucleation theory, and we attribute such deviations to changes in the structure of the confined liquid film. However, the free energy difference between the confined liquid and vapor phases agrees quantitatively with macroscopic theory, and the free energy barrier to condensation displays qualitative agreement. Overall, the present work suggests that theories attempting to capture the kinetic behavior of nanoscale systems should incorporate structural details rather than treating it as a continuum.

  7. Temperature-Correlated Changes in Phytoplankton Community Structure Are Restricted to Polar Waters.

    Science.gov (United States)

    Ward, Ben A

    2015-01-01

    Globally distributed observations of size-fractionated chlorophyll a and temperature were used to incorporate temperature dependence into an existing semi-empirical model of phytoplankton community size structure. The additional temperature-dependent term significantly increased the model's ability to both reproduce and predict observations of chlorophyll a size-fractionation at temperatures below 2°C. The most notable improvements were in the smallest (picoplankton) size-class, for which overall model fit was more than doubled, and predictive skill was increased by approximately 40%. The model was subsequently applied to generate global maps for three phytoplankton size classes, on the basis of satellite-derived estimates of surface chlorophyll a and sea surface temperature. Polar waters were associated with marked decline in the chlorophyll a biomass of the smallest cells, relative to lower latitude waters of equivalent total chlorophyll a. In the same regions a complementary increase was seen in the chlorophyll a biomass of larger size classes. These findings suggest that a warming and stratifying ocean will see a poleward expansion of the habitat range of the smallest phytoplankton, with the possible displacement of some larger groups that currently dominate. There was no evidence of a strong temperature dependence in tropical or sub-tropical regions, suggesting that future direct temperature effects on community structure at lower latitudes may be small.

  8. Distinctive Microbial Community Structure in Highly Stratified Deep-Sea Brine Water Columns

    KAUST Repository

    Bougouffa, Salim; Yang, J. K.; Lee, O. O.; Wang, Y.; Batang, Zenon B.; Al-Suwailem, Abdulaziz M.; Qian, P. Y.

    2013-01-01

    Atlantis II and Discovery are two hydrothermal and hypersaline deep-sea pools in the Red Sea rift that are characterized by strong thermohalo-stratification and temperatures steadily peaking near the bottom. We conducted comprehensive vertical profiling of the microbial populations in both pools and highlighted the influential environmental factors. Pyrosequencing of the 16S rRNA genes revealed shifts in community structures vis-à-vis depth. High diversity and low abundance were features of the deepest convective layers despite the low cell density. Surprisingly, the brine interfaces had significantly higher cell counts than the overlying deep-sea water, yet they were lowest in diversity. Vertical stratification of the bacterial populations was apparent as we moved from the Alphaproteobacteria-dominated deep sea to the Planctomycetaceae- or Deferribacteres-dominated interfaces to the Gammaproteobacteria-dominated brine layers. Archaeal marine group I was dominant in the deep-sea water and interfaces, while several euryarchaeotic groups increased in the brine. Across sites, microbial phylotypes and abundances varied substantially in the brine interface of Discovery compared with Atlantis II, despite the near-identical populations in the overlying deep-sea waters. The lowest convective layers harbored interestingly similar microbial communities, even though temperature and heavy metal concentrations were very different. Multivariate analysis indicated that temperature and salinity were the major influences shaping the communities. The harsh conditions and the low-abundance phylotypes could explain the observed correlation in the brine pools.

  9. Distinctive Microbial Community Structure in Highly Stratified Deep-Sea Brine Water Columns

    KAUST Repository

    Bougouffa, Salim

    2013-03-29

    Atlantis II and Discovery are two hydrothermal and hypersaline deep-sea pools in the Red Sea rift that are characterized by strong thermohalo-stratification and temperatures steadily peaking near the bottom. We conducted comprehensive vertical profiling of the microbial populations in both pools and highlighted the influential environmental factors. Pyrosequencing of the 16S rRNA genes revealed shifts in community structures vis-à-vis depth. High diversity and low abundance were features of the deepest convective layers despite the low cell density. Surprisingly, the brine interfaces had significantly higher cell counts than the overlying deep-sea water, yet they were lowest in diversity. Vertical stratification of the bacterial populations was apparent as we moved from the Alphaproteobacteria-dominated deep sea to the Planctomycetaceae- or Deferribacteres-dominated interfaces to the Gammaproteobacteria-dominated brine layers. Archaeal marine group I was dominant in the deep-sea water and interfaces, while several euryarchaeotic groups increased in the brine. Across sites, microbial phylotypes and abundances varied substantially in the brine interface of Discovery compared with Atlantis II, despite the near-identical populations in the overlying deep-sea waters. The lowest convective layers harbored interestingly similar microbial communities, even though temperature and heavy metal concentrations were very different. Multivariate analysis indicated that temperature and salinity were the major influences shaping the communities. The harsh conditions and the low-abundance phylotypes could explain the observed correlation in the brine pools.

  10. Thermal structure of the TTL and its relation to stratospheric-tropospheric exchange of water.

    Science.gov (United States)

    de La Torre Juárez, M.; Ao, C. O.; Schr\\O der, T. M.; Hermann, R.

    2004-12-01

    The annual cycle of the TTL fine scale thermal structure is described as captured by GPS radio occultation and the pressure levels of the ECMWF weather analysis. This annual cycle is compared to the annual cycle in water concentrations at the upper troposphere/lower stratosphere measured by HALOE. It is found that the saturation mixing ratios at the Cold Point Tropopause temperatures are consistent and sligthly below HALOE values with some temporal lag. This suggests that if dehydration mechanisms other than those associated with slow vertical asscent are working effectively, they must be counterbalanced by other hydration mechanisms. A comparison between saturation mixing ratios at the temperatures captured by GPS radio occultation and HALOE concentrations of water vapor show an annual cycle dominated by supersaturation in the boreal winter months, when the upward mass fluxes are larger, and subsaturation in the summer. The longitudinal dependence of these cycles is discussed and so is its possible implication for the seasonality of statospheric-tropospheric exchange of water.

  11. Arrester Resistive Current Measuring System Based on Heterogeneous Network

    Science.gov (United States)

    Zhang, Yun Hua; Li, Zai Lin; Yuan, Feng; Hou Pan, Feng; Guo, Zhan Nan; Han, Yue

    2018-03-01

    Metal Oxide Arrester (MOA) suffers from aging and poor insulation due to long-term impulse voltage and environmental impact, and the value and variation tendency of resistive current can reflect the health conditions of MOA. The common wired MOA detection need to use long cables, which is complicated to operate, and that wireless measurement methods are facing the problems of poor data synchronization and instability. Therefore a novel synchronous measurement system of arrester current resistive based on heterogeneous network is proposed, which simplifies the calculation process and improves synchronization, accuracy and stability and of the measuring system. This system combines LoRa wireless network, high speed wireless personal area network and the process layer communication, and realizes the detection of arrester working condition. Field test data shows that the system has the characteristics of high accuracy, strong anti-interference ability and good synchronization, which plays an important role in ensuring the stable operation of the power grid.

  12. Cardiac arrest following ventilator fire: A rare cause

    Directory of Open Access Journals (Sweden)

    K Nazeer Ahmed

    2012-01-01

    Full Text Available Operating room fires are rare events, but when occur they result in serious and sometimes fatal consequences. Anaesthesia ventilator fire leading to cardiac arrest is a rare incident and has not been reported. We report a near catastrophic ventilator fire leading to cardiac arrest in a patient undergoing subtotal thyroidectomy. In the present case sparks due to friction or electrical short circuit within the ventilator might have acted as source of ignition leading to fire and explosion in the oxygen rich environment. The patient was successfully resuscitated and revived with uneventful recovery and no adverse sequelae. The cardiac arrest was possibly due to severe hypoxia resulting from inhalation of smoke containing high concentrations of carbon monoxide and other noxious gases.

  13. Crack arrest toughness measurements with A533B steel

    International Nuclear Information System (INIS)

    Salonen, Seppo.

    1979-11-01

    This work covers crack arrest toughness measurements on A533B steel done at the Technical Research Centre of Finland. These measurements are one part of a multinational effort, involving 30 laboratories. The aim of the cooperative test program is to examine two test procedures for measuring the crack arrest toughness, to give information about their reproducibility, and to identify the factors affecting the interpretation. The principles given for the testing were easy to apply in general and the results were satisfactory. Some factors in the test runs and in the specimen's behaviour are indicated which can cause error in the results or make implementation of the test more difficult. By comparing the results from our laboratory with average values from the test program a good agreement can be seen. Crack arrest toughness values derived from the compared procedures with a static analysis agree closely, but values calculated using a dynamic analysis differ considerably. (author)

  14. Investigation on Melt-Structure-Water Interactions (MSWI) during severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Sehgal, B.R.; Yang, Z.L.; Dinh, T.N.; Nourgaliev, R.R.; Bui, V.A.; Haraldsson, H.O.; Li, H.X.; Konovakhin, M.; Paladino, D.; Leung, W.H [Royal Inst. of Tech., Stockholm (Sweden). Div. of Nuclear Power Safety

    1999-08-01

    This report is the final report for the work performed in 1998 in the research project Melt Structure Water Interactions (MSWI), under the auspices of the APRI Project, jointly funded by SKI, HSK, USNRC and the Swedish and Finnish power companies. The present report describes results of advanced analytical and experimental studies concerning melt-water-structure interactions during the course of a hypothetical severe core meltdown accident in a light water reactor (LWR). Emphasis has been placed on phenomena and properties which govern the fragmentation and breakup of melt jets and droplets, melt spreading and coolability, and thermal and mechanical loadings of a pressure vessel during melt-vessel interaction. Many of the investigations performed in support of this project have produced papers which have been published in the proceedings of technical meetings. A short summary of the results achieved in these papers is provided in this overview. Both experimental and analytical studies were performed to improve knowledge about phenomena of melt-structure-water interactions. We believe that significant technical advances have been achieved during the course of these studies. It was found that: the solidification has a strong effect on the drop deformation and breakup. Initially appearing at the drop surface and, later, thickening inwards, the solid crust layer dampens the instability waves on the drop surface and, therefore, hinders drop deformation and breakup. The drop thermal properties also affect the thermal behavior of the drop and, therefore, have impact on its deformation behavior. The jet fragmentation process is a function of many related phenomena. The fragmentation rate depends not only on the traditional parameters, e.g. the Weber number, but also on the melt physical properties, which change as the melt cools down from the liquidus to the solidus temperature. Additionally, the crust formed on the surface of the melt jet will also reduce the propensity

  15. Investigation on Melt-Structure-Water Interactions (MSWI) during severe accidents

    International Nuclear Information System (INIS)

    Sehgal, B.R.; Yang, Z.L.; Dinh, T.N.; Nourgaliev, R.R.; Bui, V.A.; Haraldsson, H.O.; Li, H.X.; Konovakhin, M.; Paladino, D.; Leung, W.H

    1999-08-01

    This report is the final report for the work performed in 1998 in the research project Melt Structure Water Interactions (MSWI), under the auspices of the APRI Project, jointly funded by SKI, HSK, USNRC and the Swedish and Finnish power companies. The present report describes results of advanced analytical and experimental studies concerning melt-water-structure interactions during the course of a hypothetical severe core meltdown accident in a light water reactor (LWR). Emphasis has been placed on phenomena and properties which govern the fragmentation and breakup of melt jets and droplets, melt spreading and coolability, and thermal and mechanical loadings of a pressure vessel during melt-vessel interaction. Many of the investigations performed in support of this project have produced papers which have been published in the proceedings of technical meetings. A short summary of the results achieved in these papers is provided in this overview. Both experimental and analytical studies were performed to improve knowledge about phenomena of melt-structure-water interactions. We believe that significant technical advances have been achieved during the course of these studies. It was found that: the solidification has a strong effect on the drop deformation and breakup. Initially appearing at the drop surface and, later, thickening inwards, the solid crust layer dampens the instability waves on the drop surface and, therefore, hinders drop deformation and breakup. The drop thermal properties also affect the thermal behavior of the drop and, therefore, have impact on its deformation behavior. The jet fragmentation process is a function of many related phenomena. The fragmentation rate depends not only on the traditional parameters, e.g. the Weber number, but also on the melt physical properties, which change as the melt cools down from the liquidus to the solidus temperature. Additionally, the crust formed on the surface of the melt jet will also reduce the propensity

  16. Water

    Science.gov (United States)

    ... drink and water in food (like fruits and vegetables). 6. Of all the earth’s water, how much is ocean or seas? 97 percent of the earth’s water is ocean or seas. 7. How much of the world’s water is frozen? Of all the water on earth, about 2 percent is frozen. 8. How much ...

  17. The Effect of Interactive, Three Dimensional, High Speed Simulations on High School Science Students' Conceptions of the Molecular Structure of Water.

    Science.gov (United States)

    Hakerem, Gita; And Others

    The Water and Molecular Networks (WAMNet) Project uses graduate student written Reduced Instruction Set Computing (RISC) computer simulations of the molecular structure of water to assist high school students learn about the nature of water. This study examined: (1) preconceptions concerning the molecular structure of water common among high…

  18. Clinical experience and skills of physicians in hospital cardiac arrest teams in Denmark: a nationwide study

    Directory of Open Access Journals (Sweden)

    Lauridsen KG

    2017-03-01

    Full Text Available Kasper G Lauridsen,1–3 Anders S Schmidt,1–3 Philip Caap,3,4 Rasmus Aagaard,2,3,5 Bo Løfgren1,3,4 1Department of Internal Medicine, 2Clinical Research Unit, Regional Hospital of Randers, Randers, 3Research Center for Emergency Medicine, Aarhus University Hospital, 4Institute of Clinical Medicine, Aarhus University, Aarhus, 5Department of Anesthesiology, Randers Regional Hospital, Denmark Background: The quality of in-hospital resuscitation is poor and may be affected by the clinical experience and cardiopulmonary resuscitation (CPR training. This study aimed to investigate the clinical experience, self-perceived skills, CPR training and knowledge of the guidelines on when to abandon resuscitation among physicians of cardiac arrest teams. Methods: We performed a nationwide cross-sectional study in Denmark. Telephone interviews were conducted with physicians in the cardiac arrest teams in public somatic hospitals using a structured questionnaire. Results: In total, 93 physicians (53% male from 45 hospitals participated in the study. Median age was 34 (interquartile range: 30–39 years. Respondents were medical students working as locum physicians (5%, physicians in training (79% and consultants (16%, and the median postgraduate clinical experience was 48 (19–87 months. Most respondents (92% felt confident in treating a cardiac arrest, while fewer respondents felt confident in performing intubation (41% and focused cardiac ultrasound (39% during cardiac arrest. Median time since last CPR training was 4 (2–10 months, and 48% had attended a European Resuscitation Council (ERC Advanced Life Support course. The majority (84% felt confident in terminating resuscitation; however, only 9% were able to state the ERC guidelines on when to abandon resuscitation. Conclusion: Physicians of Danish cardiac arrest teams are often inexperienced and do not feel competent performing important clinical skills during resuscitation. Less than half have

  19. [Cardiac arrest in spectators in German football stadiums. Precautionary measures, frequency and short-term outcome].

    Science.gov (United States)

    Luiz, T; Preisegger, T; Rombach, D; Madler, C

    2014-09-01

    Provision of medical care is an important element of safety precautions for visitors of sports arenas. The organizational requirements are especially high if cardiac arrest occurs; how this scenario is managed may thus serve as the ultimate indicator of the quality of stadium medical care. The objectives of this study were to analyze the structures and the resources available for the medical care of spectators in German professional soccer stadiums and to identify the frequency and the primary resuscitation success of cardiac arrest. In 2011 a questionnaire-based survey was performed among the clubs of the first and second German soccer leagues regarding medical care of spectators during the seasons 2008/2009 and 2009/2010. The focus was on the qualifications of emergency teams, the equipment and the incidence of cardiac arrest. A total of 15 stadiums were included (38%) in the survey. The mean number of physicians and emergency medical technicians on site was 0.6/10,000 seats and 16/10,000 seats, respectively. Of the latter, a mean of 82% (minimum 20% and maximum 100%) had received training with automatic external defibrillators. In 87% of the stadiums regular advanced life support training (ALS) was required. The mean number of defibrillators per stadium was 2.8/10,000 seats (minimum 1.3 and maximum 3.8) including 1.7 automatic defibrillators (minimum 0.4 and maximum 2.8). For patient transport, a mean of 0.65 ALS ambulance vehicles per 10,000 seats (minimum 0.14 and maximum 1.46) were available on site. In all stadiums staff members were connected via mobile radio communication with the stadium medical control room. A total of 52 cardiac arrests (=0.25/100,000 spectators) were recorded of which 96% of the patients were transported to hospitals with spontaneous circulation. Cardiac arrests are not a rare occurrence in German soccer stadiums. The participating stadiums are overall well prepared for such incidents in terms of organization, staff and technology and

  20. A crack arrest test using a toughness gradient steel plate

    International Nuclear Information System (INIS)

    Okamura, H.; Yagawa, G.; Urabe, Y.; Satoh, M.; Sano, J.

    1995-01-01

    Pressurized thermal shock (PTS) is a phenomenon that can occur in the reactor pressure vessels (RPVs) with internal pressure and is one of the most severe stress conditions that can be applied to the vessel. Preliminary research has shown that no PTS concern is likely to exist on Japanese RPVs during their design service lives. However, public acceptance of vessel integrity requires analyses and experiment in order to establish an analytical method and a database for life extension of Japanese RPVs. The Japanese PTS integrity study was carried out from FY 1983 to FY 1991 as a national project by Japan Power Engineering and Inspection Corporation (JAPEIC) under contract with Ministry of International Trade and Industry (MITI) in cooperation with LWR utilities and vendors. Here, a crack arrest test was carried out using a toughness gradient steel plate with three layers to study the concept of crack arrest toughness. Four-point bending load with thermal shock was applied to the large flat plate specimen with a surface crack. Five crack initiations and arrests were observed during the test and the propagated crack bifurcated. Finally, cracks were arrested at the boundary of the first and the second layer, except for a small segment of the crack. The first crack initiation took place slightly higher than the lower bound of K Ic data obtained by ITCT specimens. That is, the K IC concept for brittle crack initiation was verified for heavy section steel plates. The first crack arrest took place within the scatter band of K Ia and K Id data for the first layer. That is, the K Ia concept appears applicable for crack arrest of a short crack jump

  1. Mitral valve prolapse and sudden cardiac arrest in the community.

    Science.gov (United States)

    Narayanan, Kumar; Uy-Evanado, Audrey; Teodorescu, Carmen; Reinier, Kyndaron; Nichols, Gregory A; Gunson, Karen; Jui, Jonathan; Chugh, Sumeet S

    2016-02-01

    Mitral valve prolapse (MVP) is relatively common in the general population with recently reported prevalence of 1% and familial clustering (Framingham Heart Study). However, its association with ventricular arrhythmias and sudden cardiac arrest (SCA) remains controversial. The purpose of this study was to characterize the frequency and clinical profile of patients with MVP who suffer SCA in the community. Patients with SCA cases were prospectively identified in the population-based Oregon Sudden Unexpected Death Study (population ~1 million). The presence of MVP was identified from echocardiograms recorded prior but unrelated to the SCA event. The detailed clinical profile of patients with SCA and MVP was compared with that of SCA patients without MVP to identify potential differences. A total of 729 SCA patients were evaluated over a 12-year period (mean age 69.5 ± 14.8 years; 64.6% men). MVP was observed in 17 (2.3%) prior to the SCA event (95% confidence interval 1.2%-3.4%). Mitral regurgitation was present in 14 SCA patients with MVP (82.3%) and was moderate or severe in 10 (58.8%). Compared with SCA patients without MVP, SCA patients with MVP were younger (mean age 60.9 ± 16.4 years vs 69.7 ± 14.7 years; P = .02), with fewer risk factors (diabetes 5.9% vs 46.4%; P = .001; hypertension 41.2% vs 78.9%; P = .001) or known coronary disease (29.4% vs 65.6%; P MVP was observed in a small proportion (2.3%) of SCA patients in the general population, suggesting a low risk overall. Since SCA patients with MVP were characterized by younger age and relatively low cardiovascular comorbidity, a focus on imaging for valve structure/insufficiency as well as genetics could aid future risk stratification approaches. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  2. Complete maternal and fetal recovery after prolonged cardiac arrest.

    Science.gov (United States)

    Selden, B S; Burke, T J

    1988-04-01

    A case of complete maternal and fetal recovery after prolonged cardiac arrest from massive lidocaine overdose is presented. A 27-year-old woman at 15 weeks gestation had a complete neurologic recovery after 22 minutes of CPR, including 19 minutes of electromechanical dissociation and asystole, with normal fetal heart function and fetal motion confirmed by ultrasound immediately after resuscitation. The patient delivered a healthy and neurologically normal infant at 40 weeks gestation. This is the longest cardiac arrest in early pregnancy reported in the medical literature with normal maternal and fetal outcome.

  3. Hemodynamics and vasopressor support in therapeutic hypothermia after cardiac arrest

    DEFF Research Database (Denmark)

    Bro-Jeppesen, John; Kjaergaard, Jesper; Søholm, Helle

    2014-01-01

    AIM: Inducing therapeutic hypothermia (TH) in Out-of-Hospital Cardiac Arrest (OHCA) can be challenging due to its impact on central hemodynamics and vasopressors are frequently used to maintain adequate organ perfusion. The aim of this study was to assess the association between level of vasopres......AIM: Inducing therapeutic hypothermia (TH) in Out-of-Hospital Cardiac Arrest (OHCA) can be challenging due to its impact on central hemodynamics and vasopressors are frequently used to maintain adequate organ perfusion. The aim of this study was to assess the association between level...

  4. Out-of-Hospital Cardiac Arrest in Denmark

    DEFF Research Database (Denmark)

    Wissenberg Jørgensen, Mads

    challenges, due to the victim’s physical location, which brings an inherent risk of delay (or altogether absence) of recognition and treatment of cardiac arrest. A low frequency of bystander cardiopulmonary resuscitation and low 30-day survival after out-of-hospital cardiac arrest were identified nearly ten...... years ago in Denmark. These findings led to several national initiatives to strengthen bystander resuscitation attempts and advance care. Despite these nationwide efforts, it was unknown prior to this project whether these efforts resulted in changes in resuscitation attempts by bystanders and changes...

  5. Heavy metal accumulation imparts structural differences in fragrant Rosa species irrigated with marginal quality water.

    Science.gov (United States)

    Ahsan, Muhammad; Younis, Adnan; Jaskani, Muhammad Jafar; Tufail, Aasma; Riaz, Atif; Schwinghamer, Timothy; Tariq, Usman; Nawaz, Fahim

    2018-09-15

    Wastewater is an alternative to traditional sources of renewable irrigation water in agriculture, particularly in water-scarce regions. However, the possible risks due to heavy metals accumulation in plant tissues are often overlooked by producers. The present study aimed to identify heavy metals-induced structural modifications to roots of scented Rosa species that were irrigated with water of marginal quality. The chemical and mineral contents from the experimental irrigation canal water (control) and treated wastewater were below the limits recommended by the Pakistan Environmental Protection Agency (Pak-EPA) for medicinal plants. The experimentally untreated wastewater contained electrical conductivity (EC), chemical oxygen demand (COD), biological oxygen demand (BOD), and heavy metals (Co, Cu, Cd, Pb) that were above the recommended limits. The responses by wastewater-treated Rosa species (Rosa damascena, R. bourboniana, R. Gruss-an-Teplitz, and R. centifolia) were evaluated. The experimental data revealed that treated wastewater significantly increased the thickness of collenchyma (cortex and pith) and parenchyma tissues (vascular bundle, xylem, and phloem) of R. Gruss-an-Teplitz. Root dermal tissues (epidermis) of R. bourboniana also responded to treated wastewater. R. damascena and R. centifolia were the least affected species, under the experimental irrigation conditions. Collenchyma and dermal tissues were thicker in R. damascena and R. Gruss-an-Teplitz under untreated wastewater conditions. In parenchyma tissues, vascular bundles were thicker in R. damascena in untreated wastewater conditions, while the xylem and phloem of R. Gruss-an-Teplitz were thicker where treated wastewater was applied. In tissues other than the vascular bundle, the differences in anatomical metrics due to the experimental irrigation treatments were greater during the second year of the experiment than in the first year. The contents of metals other than chromium in the roots and

  6. Testing the performance of a Dynamic Global Ecosystem Model: Water balance, carbon balance, and vegetation structure

    Science.gov (United States)

    Kucharik, Christopher J.; Foley, Jonathan A.; Delire, Christine; Fisher, Veronica A.; Coe, Michael T.; Lenters, John D.; Young-Molling, Christine; Ramankutty, Navin; Norman, John M.; Gower, Stith T.

    2000-09-01

    While a new class of Dynamic Global Ecosystem Models (DGEMs) has emerged in the past few years as an important tool for describing global biogeochemical cycles and atmosphere-biosphere interactions, these models are still largely untested. Here we analyze the behavior of a new DGEM and compare the results to global-scale observations of water balance, carbon balance, and vegetation structure. In this study, we use version 2 of the Integrated Biosphere Simulator (IBIS), which includes several major improvements and additions to the prototype model developed by Foley et al. [1996]. IBIS is designed to be a comprehensive model of the terrestrial biosphere; the model represents a wide range of processes, including land surface physics, canopy physiology, plant phenology, vegetation dynamics and competition, and carbon and nutrient cycling. The model generates global simulations of the surface water balance (e.g., runoff), the terrestrial carbon balance (e.g., net primary production, net ecosystem exchange, soil carbon, aboveground and belowground litter, and soil CO2 fluxes), and vegetation structure (e.g., biomass, leaf area index, and vegetation composition). In order to test the performance of the model, we have assembled a wide range of continental and global-scale data, including measurements of river discharge, net primary production, vegetation structure, root biomass, soil carbon, litter carbon, and soil CO2 flux. Using these field data and model results for the contemporary biosphere (1965-1994), our evaluation shows that simulated patterns of runoff, NPP, biomass, leaf area index, soil carbon, and total soil CO2 flux agree reasonably well with measurements that have been compiled from numerous ecosystems. These results also compare favorably to other global model results.

  7. Structure stability of HKUST-1 towards water and ethanol and their effect on its CO2 capture properties.

    Science.gov (United States)

    Álvarez, J Raziel; Sánchez-González, Elí; Pérez, Eric; Schneider-Revueltas, Emilia; Martínez, Ana; Tejeda-Cruz, Adriana; Islas-Jácome, Alejandro; González-Zamora, Eduardo; Ibarra, Ilich A

    2017-07-18

    Water and ethanol stabilities of the crystal structure of the Cu-based metal-organic framework (MOF) HKUST-1 have been investigated. Vapour (water and ethanol) sorption isotherms and cyclability were measured by a dynamic strategy. The ethanol sorption capacity of HKUST-1 at 303 K remained unchanged contrasting water sorption (which decreased along with the sorption experiment time). Considering the binding energy of each sorbate with the open Cu(ii) sites, obtained by the use of diffusion coefficients, we showed the superior crystal stability of the HKUST-1 framework towards ethanol. Finally, a small quantity of ethanol (pre-adsorbed) slightly enhanced CO 2 capture without crystal structure degradation.

  8. Structural interactions between lipids, water and S1-S4 voltage-sensing domains.

    Science.gov (United States)

    Krepkiy, Dmitriy; Gawrisch, Klaus; Swartz, Kenton J

    2012-11-02

    Membrane proteins serve crucial signaling and transport functions, yet relatively little is known about their structures in membrane environments or how lipids interact with these proteins. For voltage-activated ion channels, X-ray structures suggest that the mobile voltage-sensing S4 helix would be exposed to the membrane, and functional studies reveal that lipid modification can profoundly alter channel activity. Here, we use solid-state NMR to investigate structural interactions of lipids and water with S1-S4 voltage-sensing domains and to explore whether lipids influence the structure of the protein. Our results demonstrate that S1-S4 domains exhibit extensive interactions with lipids and that these domains are heavily hydrated when embedded in a membrane. We also find evidence for preferential interactions of anionic lipids with S1-S4 domains and that these interactions have lifetimes on the timescale of ≤ 10(-3)s. Arg residues within S1-S4 domains are well hydrated and are positioned in close proximity to lipids, exhibiting local interactions with both lipid headgroups and acyl chains. Comparative studies with a positively charged lipid lacking a phosphodiester group reveal that this lipid modification has only modest effects on the structure and hydration of S1-S4 domains. Taken together, our results demonstrate that Arg residues in S1-S4 voltage-sensing domains reside in close proximity to the hydrophobic interior of the membrane yet are well hydrated, a requirement for carrying charge and driving protein motions in response to changes in membrane voltage. Published by Elsevier Ltd.

  9. Evaluating a novel tiered scarcity adjusted water budget and pricing structure using a holistic systems modelling approach.

    Science.gov (United States)

    Sahin, Oz; Bertone, Edoardo; Beal, Cara; Stewart, Rodney A

    2018-06-01

    Population growth, coupled with declining water availability and changes in climatic conditions underline the need for sustainable and responsive water management instruments. Supply augmentation and demand management are the two main strategies used by water utilities. Water demand management has long been acknowledged as a least-cost strategy to maintain water security. This can be achieved in a variety of ways, including: i) educating consumers to limit their water use; ii) imposing restrictions/penalties; iii) using smart and/or efficient technologies; and iv) pricing mechanisms. Changing water consumption behaviours through pricing or restrictions is challenging as it introduces more social and political issues into the already complex water resources management process. This paper employs a participatory systems modelling approach for: (1) evaluating various forms of a proposed tiered scarcity adjusted water budget and pricing structure, and (2) comparing scenario outcomes against the traditional restriction policy regime. System dynamics modelling was applied since it can explicitly account for the feedbacks, interdependencies, and non-linear relations that inherently characterise the water tariff (price)-demand-revenue system. A combination of empirical water use data, billing data and customer feedback on future projected water bills facilitated the assessment of the suitability and likelihood of the adoption of scarcity-driven tariff options for a medium-sized city within Queensland, Australia. Results showed that the tiered scarcity adjusted water budget and pricing structure presented was preferable to restrictions since it could maintain water security more equitably with the lowest overall long-run marginal cost. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Water

    International Nuclear Information System (INIS)

    Chovanec, A.; Grath, J.; Kralik, M.; Vogel, W.

    2002-01-01

    An up-date overview of the situation of the Austrian waters is given by analyzing the status of the water quality (groundwater, surface waters) and water protection measures. Maps containing information of nitrate and atrazine in groundwaters (analyses at monitoring stations), nitrate contents and biological water quality of running waters are included. Finally, pollutants (nitrate, orthophosphate, ammonium, nitrite, atrazine etc.) trends in annual mean values and median values for the whole country for the years 1992-1999 are presented in tables. Figs. 5. (nevyjel)

  11. Insights into structural and dynamical features of water at halloysite interfaces probed by DFT and classical molecular dynamics simulations.

    Science.gov (United States)

    Presti, Davide; Pedone, Alfonso; Mancini, Giordano; Duce, Celia; Tiné, Maria Rosaria; Barone, Vincenzo

    2016-01-21

    Density functional theory calculations and classical molecular dynamics simulations have been used to investigate the structure and dynamics of water molecules on kaolinite surfaces and confined in the interlayer of a halloysite model of nanometric dimension. The first technique allowed us to accurately describe the structure of the tetrahedral-octahedral slab of kaolinite in vacuum and in interaction with water molecules and to assess the performance of two widely employed empirical force fields to model water/clay interfaces. Classical molecular dynamics simulations were used to study the hydrogen bond network structure and dynamics of water adsorbed on kaolinite surfaces and confined in the halloysite interlayer. The results are in nice agreement with the few experimental data available in the literature, showing a pronounced ordering and reduced mobility of water molecules at the hydrophilic octahedral surfaces of kaolinite and confined in the halloysite interlayer, with respect to water interacting with the hydrophobic tetrahedral surfaces and in the bulk. Finally, this investigation provides new atomistic insights into the structural and dynamical properties of water-clay interfaces, which are of fundamental importance for both natural processes and industrial applications.

  12. A simple model for the initial phase of a water plasma cloud about a large structure in space

    International Nuclear Information System (INIS)

    Hastings, D.E.; Gatsonis, N.A.; Mogstad, T.

    1988-01-01

    Large structures in the ionosphere will outgas or eject neutral water and perturb the ambient neutral environment. This water can undergo charge exchange with the ambient oxygen ions and form a water plasma cloud. Additionally, water dumps or thruster firings can create a water plasma cloud. A simple model for the evolution of a water plasma cloud about a large space structure is obtained. It is shown that if the electron density around a large space structure is substantially enhanced above the ambient density then the plasma cloud will move away from the structure. As the cloud moves away, it will become unstable and will eventually break up into filaments. A true steady state will exist only if the total electron density is unperturbed from the ambient density. When the water density is taken to be consistent with shuttle-based observations, the cloud is found to slowly drift away on a time scale of many tens of milliseconds. This time is consistent with the shuttle observations

  13. Elastocapillary folding of three dimensional micro-structures using water pumped through the wafer via a silicon nitride tube

    NARCIS (Netherlands)

    Legrain, A.B.H.; Berenschot, Johan W.; Sanders, Remco G.P.; Ma, Kechun; Tas, Niels Roelof; Abelmann, Leon

    2011-01-01

    In this paper we present the first investigation of a batch method for folding of threedimensional micrometer-sized silicon nitride structures by capillary forces. Silicon nitride tubes have been designed and fabricated using DRIE at the center of the planar origami patterns of the structures. Water

  14. Water absorption, cooking properties and cell structure of gamma irradiated soybeans

    International Nuclear Information System (INIS)

    Kang, I.J.; Byun, M.W.

    1996-01-01

    Gamma irradiation was applied to soybean(Glycine max.), Hwangkeum, at dose levels of 0, 5, 10 and 20 kGy to improve the physical properties of soybeans. The time to reach a fixed moisture content was reduced depending on the increment of soaking temperatures and applied irradiation dose levels. Irradiation at 5~20 kGy resulted in reduction in soaking time of the soybeans by about 3~6 hrs at soaking temperature of 20°. The degree of cooking of soybeans in boiling water was determined by measuring the maximum cutting force of cotyledon. The cutting force to reach complete cooking was about 145g/g. Irradiation at 5~20 kGy resulted in a reduction of cooking time of soybeans by 55~75% as compared to the nonirradiated soybean. In electron microscopic observation of seed coat inner, the parenchyma of nonirradiated soybean showed tight fibrillar structure, whereas that of irradiated soybeans showed loosened and deformed structure. The microstructure of compressed cells and cotyledon epidermis was also deformed by gamma irradiation. In subcellular structure of cotyledon, the roundness of protein body was deformed and changed to spike shape at 20 kGy. Also, the size of lipid body decreased as the irradiation dose levels increased

  15. Structural analysis of steam generator internals following feed water main steam line break: DLF approach

    International Nuclear Information System (INIS)

    Bhasin, Vivek; Kushwaha, H.S.; Mahajan, S.C.; Kakodkar, A.

    1993-01-01

    In order to evaluate the possible release of radioactivity in extreme events, some postulated accidents are analysed and studied during the design stage of Steam Generator (SG). Among the various accidents postulated, the most important are Feed Water Line Break (FWLB) and Main Steam Line Break (MSLB). This report concerns with dynamic structural analysis of SG internals following FWLB/MSLB. The pressure/drag-force time histories considered were corresponding to the conditions leading to the accident of maximum potential. The SG internals were analysed using two approaches of structural dynamics. In first approach simplified DLF method was adopted. This method yields an upper bound values of stresses and deflection. In the second approach time history analysis by Mode Superposition Technique was adopted. This approach gives more realistic results. The structure was qualified as per ASME B and PV Code SecIII NB. It was concluded that in all the components except perforated flow distribution plate, the stress values based on elastic analysis are within the limits specified by ASME Code. In case of perforated flow distribution plate during the MSLB transient the stress values based on elastic analysis are higher than the ASME Code limits. Therefore, its limit load analysis had to be done. Finally, the collapse pressure evaluated using limit load analysis was shown to be within the limits of ASME B and PV Code SecIII Nb. (author). 31 refs., 94 figs., 16 tabs

  16. Analyzing structural variations along strike in a deep-water thrust belt

    Science.gov (United States)

    Totake, Yukitsugu; Butler, Robert W. H.; Bond, Clare E.; Aziz, Aznan

    2018-03-01

    We characterize a deep-water fold-thrust arrays imaged by a high-resolution 3D seismic dataset in the offshore NW Borneo, Malaysia, to understand the kinematics behind spatial arrangement of structural variations throughout the fold-thrust system. The seismic volume used covers two sub-parallel fold trains associated with a series of fore-thrusts and back-thrusts. We measured fault heave, shortening value, fold geometries (forelimb dip, interlimb angle and crest depth) along strike in individual fold trains. Heave plot on strike projection allows to identify individual thrust segments showing semi-elliptical to triangular to bimodal patterns, and linkages of these segments. The linkage sites are marked by local minima in cumulative heave. These local heave minima are compensated by additional structures, such as small imbricate thrusts and tight folds indicated by large forelimb dip and small interlimb angle. Complementary profiles of the shortening amount for the two fold trains result in smoother gradient of total shortening across the structures. We interpret this reflects kinematic interaction between two fold-thrust trains. This type of along-strike variation analysis provides comprehensive understanding of a fold-thrust system and may provide an interpretative strategy for inferring the presence of complex multiple faults in less well-imaged parts of seismic volumes.

  17. Structural Changes of Lignin after Liquid Hot Water Pretreatment and Its Effect on the Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Wen Wang

    2016-01-01

    Full Text Available During liquid hot water (LHW pretreatment, lignin is mostly retained in the pretreated biomass, and the changes in the chemical and structural characteristics of lignin should probably refer to re-/depolymerization, solubilization, or glass transition. The residual lignin could influence the effective enzymatic hydrolysis of cellulose. The pure lignin was used to evaluate the effect of LHW process on its structural and chemical features. The surface morphology of LHW-treated lignin observed with the scanning electron microscopy (SEM was more porous and irregular than that of untreated lignin. Compared to the untreated lignin, the surface area, total pore volume, and average pore size of LHW-treated lignin tested with the Brunner-Emmet-Teller (BET measurement were increased. FTIR analysis showed that the chemical structure of lignin was broken down in the LHW process. Additionally, the impact of untreated and treated lignin on the enzymatic hydrolysis of cellulose was also explored. The LHW-treated lignin had little impact on the cellulase adsorption and enzyme activities and somehow could improve the enzymatic hydrolysis of cellulose.

  18. Structural transformations, water incorporation and transport properties of tin-substituted barium indate

    Science.gov (United States)

    Cichy, Kacper; Skubida, Wojciech; Świerczek, Konrad

    2018-06-01

    Incorporation of water into tin-substituted BaIn1-xSnxO3-δ (x = 0.1-0.3) is shown to influence crystal structure at room temperature, structural transformations at high temperatures and ionic transport properties of the materials. Increasing tin content stabilizes oxygen vacancy-disordered perovskite-type phase, which together with large changes of the unit cell volume occurring during hydration and dehydration processes, result in a complex structural behavior, as documented by high-temperature X-ray diffraction and thermogravimetric studies. Impedance spectroscopy measurements at elevated temperatures (350-800 °C) revealed very high proton conductivity in BaIn.8Sn.2O3-δ, exceeding 1.1·10-3 S cm-1 at 500 °C, with high values of the transference number in wet air. At the same time, relaxation kinetics of the electrical conductivity showed a monotonous nature, which indicates negligible component of the electronic hole conductivity in the hydrated material. The oxides are extremely moisture-sensitive, which results in a significant mechanical stability problems, affecting possibility to prepare electrolyte membranes.

  19. Dielectric Dispersion Studies Indicate Change in Structure of Water by Potentised Homeopathic Medicines

    Science.gov (United States)

    Mahata, C. R.

    2012-12-01

    Response of living bodies to different vastly `diluted' homeopathic medicines are different (rejecting the sceptic's view of `placebo' effect), though they are chemically same. Till now there is no satisfactory answer to how one such medicine differs from another in terms of scientifically measurable parameters. This paper tries to address this basic issue by taking two medicines of the same potency and two different potencies of the same medicine, namely, Arnica Mont 30c, 200c and Anacardium Orient 30c, 200c. These potencies are well above the Avogadro limit. The investigation reported here proceeds with the concept of `induced molecular structure' advanced by a number of scientists. Dielectric dispersion is used as the tool for experimental verification. It is based on the fact that when the exciting frequency of applied electric field equals the characteristic frequency, then macromolecules resonate leading to anomalous dielectric dispersion associated with sharp increase in dielectric loss, the resonance frequencies being different for macromolecules of different structures or dimensions. The results suggest that medicine- and potency-specific attributes are acquired by the vehicle (i.e. water) in the form of macromolecules generated by the potentization process of homeopathy making one medicine structurally different from another.

  20. Directed weighted network structure analysis of complex impedance measurements for characterizing oil-in-water bubbly flow.

    Science.gov (United States)

    Gao, Zhong-Ke; Dang, Wei-Dong; Xue, Le; Zhang, Shan-Shan

    2017-03-01

    Characterizing the flow structure underlying the evolution of oil-in-water bubbly flow remains a contemporary challenge of great interests and complexity. In particular, the oil droplets dispersing in a water continuum with diverse size make the study of oil-in-water bubbly flow really difficult. To study this issue, we first design a novel complex impedance sensor and systematically conduct vertical oil-water flow experiments. Based on the multivariate complex impedance measurements, we define modalities associated with the spatial transient flow structures and construct modality transition-based network for each flow condition to study the evolution of flow structures. In order to reveal the unique flow structures underlying the oil-in-water bubbly flow, we filter the inferred modality transition-based network by removing the edges with small weight and resulting isolated nodes. Then, the weighted clustering coefficient entropy and weighted average path length are employed for quantitatively assessing the original network and filtered network. The differences in network measures enable to efficiently characterize the evolution of the oil-in-water bubbly flow structures.

  1. Geo - hydrological investigations and impact of water harvesting structures on groundwater potential in Anantapur District, Andhra Pradesh, India.

    Science.gov (United States)

    Suryanarayana, K V; Krishnaiah, S; Khokalay, Murthy Rao V

    2010-10-01

    In this paper, the data pertaining to the rainfall, its departure from normal, moving mean rainfall, depth of water levels in pre-monsoon and post-monsoon seasons, groundwater availability, groundwater utilization and impact of storage of water in large water bodies are analyzed graphically. The results indicate that the groundwater is over exploited in many places in Anantapur District (India). The groundwater levels found fluctuating, when compared the observations in pre-monsoon and post-monsoon seasons. Hence, it is concluded that the construction of water harvesting structures at suitable locations will have a definite impact on the groundwater potential in Anantapur District.

  2. Structural investigation of water-acetonitrile mixtures: An ab initio, molecular dynamics and X-ray diffraction study

    International Nuclear Information System (INIS)

    Bako, Imre; Megyes, Tuende; Palinkas, Gabor

    2005-01-01

    In this work, we present a study on water-acetonitrile (AN) mixtures by molecular dynamics ab initio and X-ray diffraction techniques. Comparison of the experimental total G(r) functions of the mixtures with the results of molecular dynamics simulation shows an overall good agreement. The properties of hydrogen bonded clusters (water clusters, and water-AN clusters) in these mixtures have been determined. Two different types of AN-water dimers were identified by ab initio quantum chemical calculation. One of these structures proved to be a true H-bonded dimer and the other a dipole bound dimer

  3. Water

    Science.gov (United States)

    ... can be found in some metal water taps, interior water pipes, or pipes connecting a house to ... reduce or eliminate lead. See resources below. 5. Children and pregnant women are especially vulnerable to the ...

  4. Hydrogen bond dynamics and water structure in glucose-water solutions by depolarized Rayleigh scattering and low-frequency Raman spectroscopy

    Science.gov (United States)

    Paolantoni, Marco; Sassi, Paola; Morresi, Assunta; Santini, Sergio

    2007-07-01

    The effect of glucose on the relaxation process of water at picosecond time scales has been investigated by depolarized Rayleigh scattering (DRS) experiments. The process is assigned to the fast hydrogen bonding dynamics of the water network. In DRS spectra this contribution can be safely separated from the slower relaxation process due to the sugar. The detected relaxation time is studied at different glucose concentrations and modeled considering bulk and hydrating water contributions. As a result, it is found that in diluted conditions the hydrogen bond lifetime of proximal water molecules becomes about three times slower than that of the bulk. The effect of the sugar on the hydrogen bond water structure is investigated by analyzing the low-frequency Raman (LFR) spectrum sensitive to intermolecular modes. The addition of glucose strongly reduces the intensity of the band at 170cm-1 assigned to a collective stretching mode of water molecules arranged in cooperative tetrahedral domains. These findings indicate that proximal water molecules partially lose the tetrahedral ordering typical of the bulk leading to the formation of high density environments around the sugar. Thus the glucose imposes a new local order among water molecules localized in its hydration shell in which the hydrogen bond breaking dynamics is sensitively retarded. This work provides new experimental evidences that support recent molecular dynamics simulation and thermodynamics results.

  5. [Algal community structure and water quality assessment on drawdown area of Kaixian waters in Three Gorges Reservoir during winter storage period].

    Science.gov (United States)

    Guo, Jing-Song; Xie, Dan; Li, Zhe; Chen, Yuan; Sun, Zhi-Yu; Chen, Yong-Bo; Long, Man

    2012-04-01

    The old town area of Kaixian county was flooded and showed reservoir characteristics after the water level of Three Gorges Reservoir got 172. 8 m in December 2008. The aquatic ecology and nutritional status of Kaixian drawdown area after water storage are still rarely reported. To understand the current water environment and changes in algal community structure of Kaixian drawdown area after 172.8 m water level, the algal composition, abundance, biomass distribution and changes of its sampling spots including Hanfeng Lake were observed twice during winter storage period in January and December 2009. The trends in phytoplankton community structure were analyzed and the water quality assessment of nutritional status was carried out. The results indicated that 6 phylums, 37 genera, 69 species of phytoplankton in total were identified in the two sampling, and the dominant species were Dinophyta and Cryptophyta. The cell density and biomass in December 2009 were lower than those in January 2009. The evaluation results of algal population structure and pollution indicators showed that the nutrition level of Kaixian drawdown area during the winter storage period was mesotrophic to eutrophic type, while diversity analysis result indicated moderate pollution.

  6. Artificial-Crack-Behavior Test Evaluation of the Water-Leakage Repair Materials Used for the Repair of Water-Leakage Cracks in Concrete Structures

    Directory of Open Access Journals (Sweden)

    Soo-Yeon Kim

    2016-09-01

    Full Text Available There are no existing standard test methods at home and abroad that can verify the performance of water leakage repair materials, and it is thus very difficult to perform quality control checks in the field of water leakage repair. This study determined that the key factors that have the greatest impact on the water leakage repair materials are the micro-behaviors of cracks, and proposed an artificial-crack-behavior test method for the performance verification of the repair materials. The performance of the 15 kinds of repair materials that are currently being used in the field of water leakage repair was evaluated by applying the proposed test method. The main aim of such a test method is to determine if there is water leakage by injecting water leakage repair materials into a crack behavior test specimen with an artificial 5-mm crack width, applying a 2.5 mm vertical behavior load at 100 cycles, and applying 0.3 N/mm2 constant water pressure. The test results showed that of the 15 kinds of repair materials, only two effectively sealed the crack and thus stopped the water leakage. The findings of this study confirmed the effectiveness of the proposed artificial-crack-behavior test method and suggest that it can be used as a performance verification method for checking the responsiveness of the repair materials being used in the field of water leakage repair to the repetitive water leakage behaviors that occur in concrete structures. The study findings further suggest that the use of the proposed test method makes it possible to quantify the water leakage repair quality control in the field.

  7. Structure and dynamics of water and lipid molecules in charged anionic DMPG lipid bilayer membranes

    International Nuclear Information System (INIS)

    Rønnest, A. K.; Peters, G. H.; Hansen, F. Y.; Taub, H.; Miskowiec, A.

    2016-01-01

    Molecular dynamics simulations have been used to investigate the influence of the valency of counter-ions on the structure of freestanding bilayer membranes of the anionic 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) lipid at 310 K and 1 atm. At this temperature, the membrane is in the fluid phase with a monovalent counter-ion and in the gel phase with a divalent counter-ion. The diffusion constant of water as a function of its depth in the membrane has been determined from mean-square-displacement calculations. Also, calculated incoherent quasielastic neutron scattering functions have been compared to experimental results and used to determine an average diffusion constant for all water molecules in the system. On extrapolating the diffusion constants inferred experimentally to a temperature of 310 K, reasonable agreement with the simulations is obtained. However, the experiments do not have the sensitivity to confirm the diffusion of a small component of water bound to the lipids as found in the simulations. In addition, the orientation of the dipole moment of the water molecules has been determined as a function of their depth in the membrane. Previous indirect estimates of the electrostatic potential within phospholipid membranes imply an enormous electric field of 10 8 –10 9 V m −1 , which is likely to have great significance in controlling the conformation of translocating membrane proteins and in the transfer of ions and molecules across the membrane. We have calculated the membrane potential for DMPG bilayers and found ∼1 V (∼2 ⋅ 10 8 V m −1 ) when in the fluid phase with a monovalent counter-ion and ∼1.4 V (∼2.8 ⋅ 10 8 V m −1 ) when in the gel phase with a divalent counter-ion. The number of water molecules for a fully hydrated DMPG membrane has been estimated to be 9.7 molecules per lipid in the gel phase and 17.5 molecules in the fluid phase, considerably smaller than inferred experimentally for 1,2-dimyristoyl-sn-glycero-3

  8. Structure and dynamics of water and lipid molecules in charged anionic DMPG lipid bilayer membranes

    Energy Technology Data Exchange (ETDEWEB)

    Rønnest, A. K.; Peters, G. H.; Hansen, F. Y., E-mail: flemming@kemi.dtu.dk [Department of Chemistry, Technical University of Denmark, IK 207 DTU, DK-2800 Lyngby (Denmark); Taub, H.; Miskowiec, A. [Department of Physics and Astronomy and the University of Missouri Research Reactor,University of Missouri, Columbia, Missouri 65211 (United States)

    2016-04-14

    Molecular dynamics simulations have been used to investigate the influence of the valency of counter-ions on the structure of freestanding bilayer membranes of the anionic 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) lipid at 310 K and 1 atm. At this temperature, the membrane is in the fluid phase with a monovalent counter-ion and in the gel phase with a divalent counter-ion. The diffusion constant of water as a function of its depth in the membrane has been determined from mean-square-displacement calculations. Also, calculated incoherent quasielastic neutron scattering functions have been compared to experimental results and used to determine an average diffusion constant for all water molecules in the system. On extrapolating the diffusion constants inferred experimentally to a temperature of 310 K, reasonable agreement with the simulations is obtained. However, the experiments do not have the sensitivity to confirm the diffusion of a small component of water bound to the lipids as found in the simulations. In addition, the orientation of the dipole moment of the water molecules has been determined as a function of their depth in the membrane. Previous indirect estimates of the electrostatic potential within phospholipid membranes imply an enormous electric field of 10{sup 8}–10{sup 9} V m{sup −1}, which is likely to have great significance in controlling the conformation of translocating membrane proteins and in the transfer of ions and molecules across the membrane. We have calculated the membrane potential for DMPG bilayers and found ∼1 V (∼2 ⋅ 10{sup 8} V m{sup −1}) when in the fluid phase with a monovalent counter-ion and ∼1.4 V (∼2.8 ⋅ 10{sup 8} V m{sup −1}) when in the gel phase with a divalent counter-ion. The number of water molecules for a fully hydrated DMPG membrane has been estimated to be 9.7 molecules per lipid in the gel phase and 17.5 molecules in the fluid phase, considerably smaller than inferred experimentally for 1

  9. Beneficial effects on water management of simple hydraulic structures in wetland systems: the Vallevecchia case study, Italy.

    Science.gov (United States)

    Carrer, G M; Bonato, M; Smania, D; Barausse, A; Comis, C; Palmeri, L

    2011-01-01

    Conflicting water uses in coastal zones demand integrated approaches to achieve sustainable water resources management, protecting water quality while allowing those human activities which rely upon aquatic ecosystem services to thrive. This case study shows that the creation and simple management of hydraulic structures within constructed wetlands can markedly reduce the non-point pollution from agriculture and, simultaneously, benefit agricultural activities, particularly during hot and dry periods. The Vallevecchia wetland system is based on a reclaimed 900 ha-large drainage basin in Northern Italy, where droughts recently impacted agriculture causing water scarcity and saltwater intrusion. Rainwater and drained water are recirculated inside the system to limit saltwater intrusion, provide irrigation water during dry periods and reduce the agricultural nutrient loads discharged into the bordering, eutrophic Adriatic Sea. Monitoring (2003-2009) of water quality and flows highlights that the construction (ended in 2005) of a gated spillway to control the outflow, and of a 200,000 m3 basin for water storage, dramatically increased the removal of nutrients within the system. Strikingly, this improvement was achieved with a minimal management effort, e.g., each year the storage basin was filled once: a simple management of the hydraulic structures would greatly enhance the system efficiency, and store more water to irrigate and limit saltwater intrusion.

  10. Fluid-structure interaction analysis of a water pool under loading caused by steam injection

    International Nuclear Information System (INIS)

    Timperi, A.; Paettikangas, T.; Niemi, J.; Ilvonen, M.

    2006-04-01

    CFD and structural analysis codes. MpCCI 3.0 was used for coupling Fluent CFD code with ABAQUS FE code. ES-FSI was used for coupling Star-CD CFD code with ABAQUS. FSI analyses, in which the calculation was carried out entirely in ABAQUS, were also performed. In this case, acoustic elements were used for the fluid and the acoustic and structural domains were coupled. FSI calculations were performed for simple test cases and for a test pool at Lappeenranta University of Technology. The Method of Images was studied as an alternative method for the analyses of the pool. Particularly, the determination of pressure source for the method was studied. Earlier work carried out with the homogenous two-phase model was continued by testing the model with Fluent. Calculation of condensation of steam in a water pool was tested with a new implementation. The two-directionally coupled simulations of the pool with MpCCI and ES-FSI were found to be numerically instable. It was concluded that an implicit coupling method may have to be used in order to avoid the instability. Calculations of the pool were finally performed by using one directional coupling. In the simulations with MpCCI, the incompressible and compressible VOF models of Fluent were used. With ES-FSI, the incompressible VOF model of Star-CD was used for modelling the beginning of a steam injection experiment. The magnitudes of pressure and stress peaks in the simulation and experiment were of comparable size. Otherwise, however, differences between the simulation and experiment were large due to the simplifications used in the simulation. Results obtained with the acoustic-structural FE analyses were compared to analytical and experimental results. The results indicated that the coupled acoustic-structural analysis can be used for calculating the coupled Eigenmodes of BWR pressure suppression pools. (au)

  11. Fluid-structure interaction analysis of a water pool under loading caused by steam injection

    Energy Technology Data Exchange (ETDEWEB)

    Timperi, A.; Paettikangas, T.; Niemi, J.; Ilvonen, M. [VTT Technical Researc Centre of Finland (Finland)

    2006-04-15

    CFD and structural analysis codes. MpCCI 3.0 was used for coupling Fluent CFD code with ABAQUS FE code. ES-FSI was used for coupling Star-CD CFD code with ABAQUS. FSI analyses, in which the calculation was carried out entirely in ABAQUS, were also performed. In this case, acoustic elements were used for the fluid and the acoustic and structural domains were coupled. FSI calculations were performed for simple test cases and for a test pool at Lappeenranta University of Technology. The Method of Images was studied as an alternative method for the analyses of the pool. Particularly, the determination of pressure source for the method was studied. Earlier work carried out with the homogenous two-phase model was continued by testing the model with Fluent. Calculation of condensation of steam in a water pool was tested with a new implementation. The two-directionally coupled simulations of the pool with MpCCI and ES-FSI were found to be numerically instable. It was concluded that an implicit coupling method may have to be used in order to avoid the instability. Calculations of the pool were finally performed by using one directional coupling. In the simulations with MpCCI, the incompressible and compressible VOF models of Fluent were used. With ES-FSI, the incompressible VOF model of Star-CD was used for modelling the beginning of a steam injection experiment. The magnitudes of pressure and stress peaks in the simulation and experiment were of comparable size. Otherwise, however, differences between the simulation and experiment were large due to the simplifications used in the simulation. Results obtained with the acoustic-structural FE analyses were compared to analytical and experimental results. The results indicated that the coupled acoustic-structural analysis can be used for calculating the coupled Eigenmodes of BWR pressure suppression pools. (au)

  12. Network structure and institutional complexity in an ecology of water management games

    Directory of Open Access Journals (Sweden)

    Mark Lubell

    2014-12-01

    Full Text Available Social-ecological systems are governed by a complex of ecology of games featuring multiple actors, policy institutions, and issues, and not just single institutions operating in isolation. We update Long's (1958 ecology of games to analyze the coordinating roles of actors and institutions in the context of the ecology of water management games in San Francisco Bay, California. The ecology of games is operationalized as a bipartite network with actors participating in institutions, and exponential random graph models are used to test hypotheses about the structural features of the network. We found that policy coordination is facilitated mostly by federal and state agencies and collaborative institutions that span geographic boundaries. Network configurations associated with closure show the most significant departures from the predicted model values, consistent with the Berardo and Scholz (2010 "risk hypothesis" that closure is important for solving cooperation problems.

  13. Interfacial structures of confined air-water two-phase bubbly flow

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.; Ishii, M.; Wu, Q.; McCreary, D.; Beus, S.G.

    2000-08-01

    The interfacial structure of the two-phase flows is of great importance in view of theoretical modeling and practical applications. In the present study, the focus is made on obtaining detailed local two-phase parameters in the air-water bubbly flow in a rectangular vertical duct using the double-sensor conductivity probe. The characteristic wall-peak is observed in the profiles of the interracial area concentration and the void fraction. The development of the interfacial area concentration along the axial direction of the flow is studied in view of the interfacial area transport and bubble interactions. The experimental data is compared with the drift flux model with C{sub 0} = 1.35.

  14. Lightweight concrete materials and structural systems for water tanks for thermal storage. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Buckman, R.W. Jr.; Elia, G.G.; Ichikawa, Y.

    1980-12-01

    Thermally efficient hot water storage tanks were designed, fabricated and evaluated. The tanks were made using cellular concrete at a nominal density of 100 lb/ft/sup 3/ for the structural elements and at a 30 lb/ft/sup 3/ density for the insulating elements. Thermal performance testing of the tanks was done using a static decay test since the test procedure specified in ASHRAE 94-77 was not experimentally practical. A series of composition modifications to the cellular concrete mix were investigated and the addition of alkaline resistant glass fibers was found to enhance the mechanical properties at no sacrifice in thermal behavior. Economic analysis indicated that cellular concrete provides a cost-effective insulating material. The total portability of the plant for producing cellular concrete makes cellular concrete amenable to on-site fabrication and uniquely adaptable to retrofit applications.

  15. Interfacial structures of confined air-water two-phase bubbly flow

    International Nuclear Information System (INIS)

    Kim, S.; Ishii, M.; Wu, Q.; McCreary, D.; Beus, S.G.

    2000-01-01

    The interfacial structure of the two-phase flows is of great importance in view of theoretical modeling and practical applications. In the present study, the focus is made on obtaining detailed local two-phase parameters in the air-water bubbly flow in a rectangular vertical duct using the double-sensor conductivity probe. The characteristic wall-peak is observed in the profiles of the interracial area concentration and the void fraction. The development of the interfacial area concentration along the axial direction of the flow is studied in view of the interfacial area transport and bubble interactions. The experimental data is compared with the drift flux model with C 0 = 1.35

  16. Light water reactor fuel analysis code FEMAXI-7; model and structure

    International Nuclear Information System (INIS)

    Suzuki, Motoe; Udagawa, Yutaka; Saitou, Hiroaki

    2011-03-01

    A light water reactor fuel analysis code FEMAXI-7 has been developed for the purpose of analyzing the fuel behavior in both normal conditions and anticipated transient conditions. This code is an advanced version which has been produced by incorporating the former version FEMAXI-6 with numerous functional improvements and extensions. In FEMAXI-7, many new models have been added and parameters have been clearly arranged. Also, to facilitate effective maintenance and accessibility of the code, modularization of subroutines and functions have been attained, and quality comment descriptions of variables or physical quantities have been incorporated in the source code. With these advancements, the FEMAXI-7 code has been upgraded to a versatile analytical tool for high burnup fuel behavior analyses. This report describes in detail the design, basic theory and structure, models and numerical method, and improvements and extensions. (author)

  17. Light water reactor fuel analysis code FEMAXI-7. Model and structure

    International Nuclear Information System (INIS)

    Suzuki, Motoe; Udagawa, Yutaka; Nagase, Fumihisa; Saitou, Hiroaki

    2013-07-01

    A light water reactor fuel analysis code FEMAXI-7 has been developed for the purpose of analyzing the fuel behavior in both normal conditions and anticipated transient conditions. This code is an advanced version which has been produced by incorporating the former version FEMAXI-6 with numerous functional improvements and extensions. In FEMAXI-7, many new models have been added and parameters have been clearly arranged. Also, to facilitate effective maintenance and accessibility of the code, modularization of subroutines and functions have been attained, and quality comment descriptions of variables or physical quantities have been incorporated in the source code. With these advancements, the FEMAXI-7 code has been upgraded to a versatile analytical tool for high burnup fuel behavior analyses. This report describes in detail the design, basic theory and structure, models and numerical method of FEMAXI-7, and its improvements and extensions. (author)

  18. Synthesis, Crystal Structure and Water Vapor Adsorption Properties of a Porous Supramolecular Architecture

    Directory of Open Access Journals (Sweden)

    Rui Qiao

    2017-10-01

    Full Text Available A new complex, [Cu4(HL4(H2O14] (1, H3L·HCl = 5-((4-carboxypiperidin-1-ylmethylisophthalic acid hydrochloride, has been prepared and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and powder X-ray diffraction (PXRD. The result of the X-ray diffraction analysis reveals that the complex crystallizes in monoclinic, space group C2/c and three unique Cu(II atoms that are connected by partially deprotonated HL2− anion to form a cyclic structure. The rich hydrogen bonding and π-π non-covalent packing interactions extend cyclic units into a three-dimensional (3D supramolecular polymer. Moreover, the thermogravimetric (TG analysis and water vapor adsorption property of 1 were also discussed.

  19. Stock structure of Atlantic herring Clupea harengus in the Norwegian Sea and adjacent waters

    DEFF Research Database (Denmark)

    Pampoulie, Christophe; Slotte, Aril; Oskarsson, Guomundur J.

    2015-01-01

    The genetic structure of Atlantic herring Clupea harengus L. was investigated in its north-easterly distribution in the Norwegian Sea and adjacent waters, using 23 neutral and one non-neutral (Cpa111) microsatellite loci. Fish from the suspected 2 main populations-the Norwegian spring......-spawning herring (NSSH) and the Icelandic summer-spawning herring (ISSH)-were collected at spawning locations in their respective spawning seasons from 2009 to 2012. Samples were also collected from Norwegian autumn spawning locations, from different local Norwegian fjords such as the inner part...... of Trondheimsfjorden, Lindas pollene, Landvikvannet and Lusterfjorden, as well as from suspected Faroese spawning components. The observed level of genetic differentiation was significant but low (F-ST = 0.007) and mostly attributable to the differentiation of the local Norwegian fjord populations. The locus Cpa111...

  20. Unusual polar filament structure in two microsporidia from water reservoirs with radionuclide and organic pollution

    International Nuclear Information System (INIS)

    Ovcharenko, M.; Molloy, D.; Wita, I.

    1998-01-01

    Two species of microsporidia with the unusual polar filament structure were found in Cricotopus silvestris and Microtendipes pedellus larvae which were collected near the zone of influence of the Chernobyl atomic power station (Ukraine) and from a high polluted pond in the Mazurian region of Poland. The first microsporidium had separate unikaryotic spores and was assigned to the family Unikaryonidae Sprague. The diameter of the middle coil of the triple-coiled polar filament of this microsporidium was larger than its two other coils. The observed polar filament was thus neither of isofilar nor of the classical anisofilar type. The second polysporoblastic microsporidium has unikaryotic spores and an uncoiled polar filament and was placed in the family Thelohaniidae Hazard and Oldacre. The rare single macrospores of this microsporidium have a double set of the polar filament complex. The relationship between ultrastructural features of microsporidian spores and water pollution is discussed. (author)

  1. Standardized EEG interpretation accurately predicts prognosis after cardiac arrest

    NARCIS (Netherlands)

    Westhall, Erik; Rossetti, Andrea O.; van Rootselaar, Anne-Fleur; Wesenberg Kjaer, Troels; Horn, Janneke; Ullén, Susann; Friberg, Hans; Nielsen, Niklas; Rosén, Ingmar; Åneman, Anders; Erlinge, David; Gasche, Yvan; Hassager, Christian; Hovdenes, Jan; Kjaergaard, Jesper; Kuiper, Michael; Pellis, Tommaso; Stammet, Pascal; Wanscher, Michael; Wetterslev, Jørn; Wise, Matt P.; Cronberg, Tobias; Saxena, Manoj; Miller, Jennene; Inskip, Deborah; Macken, Lewis; Finfer, Simon; Eatough, Noel; Hammond, Naomi; Bass, Frances; Yarad, Elizabeth; O'Connor, Anne; Bird, Simon; Jewell, Timothy; Davies, Gareth; Ng, Karl; Coward, Sharon; Stewart, Antony; Micallef, Sharon; Parker, Sharyn; Cortado, Dennis; Gould, Ann; Harward, Meg; Thompson, Kelly; Glass, Parisa; Myburgh, John; Smid, Ondrej; Belholavek, Jan; Juffermans, Nicole P.; Boerma, EC

    2016-01-01

    To identify reliable predictors of outcome in comatose patients after cardiac arrest using a single routine EEG and standardized interpretation according to the terminology proposed by the American Clinical Neurophysiology Society. In this cohort study, 4 EEG specialists, blinded to outcome,

  2. Endothelial Dysfunction in Resuscitated Cardiac Arrest (ENDO-RCA)

    DEFF Research Database (Denmark)

    Meyer, Anna Sina P; Ostrowski, Sisse Rye; Kjærgaard, Jesper

    2016-01-01

    BACKGROUND: Morbidity and mortality following initial survival of cardiac arrest remain high despite great efforts to improve resuscitation techniques and post-resuscitation care, in part due to the ischemia-reperfusion injury secondary to the restoration of the blood circulation. Patients resusc...

  3. 19 CFR 162.63 - Arrests and seizures.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Arrests and seizures. 162.63 Section 162.63 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) INSPECTION, SEARCH, AND SEIZURE Controlled Substances, Narcotics, and Marihuana § 162...

  4. Growth arrest despite growth hormone replacement, post-craniopharyngioma surgery.

    Science.gov (United States)

    DeVile, C J; Hayward, R D; Neville, B G; Grant, D B; Stanhope, R

    1995-01-01

    Children with growth failure, whether secondary to an endocrinopathy such as growth hormone deficiency or secondary to neurological handicap with poor nutrient intake, grow at a subnormal rate but it is most unusual for a child to have complete growth arrest. PMID:7745571

  5. Cdc20 control of cell fate during prolonged mitotic arrest

    DEFF Research Database (Denmark)

    Nilsson, Jakob

    2011-01-01

    The fate of cells arrested in mitosis by antimitotic compounds is complex but is influenced by competition between pathways promoting cell death and pathways promoting mitotic exit. As components of both of these pathways are regulated by Cdc20-dependent degradation, I hypothesize that variations...

  6. Outcomes After Cardiac Arrest in an Adult Burn Center

    Science.gov (United States)

    2013-12-07

    of in-hospital CA are likely to report widely varying survival rates as a result of study populations with characteristic but distinct demo- graphics ...Rehabil 1997;18:S119. [2] Sandroni C, Nolan J. In-hospital cardiac arrest: incidence, prognosis and possible measures to improve survival. Intens Care Med

  7. Trichostrongylus colubriformis rDNA polymorphism associated with arrested development

    Czech Academy of Sciences Publication Activity Database

    Langrová, I.; Zouhar, M.; Vadlejch, J.; Borovský, M.; Jankovská, I.; Lytvynets, Andrej

    2008-01-01

    Roč. 103, č. 2 (2008), s. 401-403 ISSN 0932-0113 Institutional research plan: CEZ:AV0Z50110509 Keywords : arrested development * polymorphism * rDNA Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.473, year: 2008

  8. Anaphylactic shock and cardiac arrest caused by thiamine infusion

    DEFF Research Database (Denmark)

    Juel, Jacob; Pareek, Manan; Langfrits, Christian Sigvald

    2013-01-01

    intoxication and developed cardiac arrest due to anaphylactic shock following intravenous thiamine infusion. The patient was successfully resuscitated after 15 min and repeated epinephrine administrations. He was discharged in good health after 14 days. This case report emphasises both the importance...

  9. Lupeol induces S-phase arrest and mitochondria-mediated ...

    Indian Academy of Sciences (India)

    48

    Lupeol induces S-phase arrest and mitochondria-mediated apoptosis in cervical cancer cells. Nupoor Prasad1, Akash Sabarwal2, Umesh C. S. Yadav1, Rana P. Singh2,*. 1School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India. 2Cancer Biology Laboratory, School of Life Sciences, Jawaharlal ...

  10. Cardiac Arrest after Local Anaesthetic Toxicity in a Paediatric Patient

    Directory of Open Access Journals (Sweden)

    Liana Maria Torres de Araújo Azi

    2016-01-01

    Full Text Available We report a case of a paediatric patient undergoing urological procedure in which a possible inadvertent intravascular or intraosseous injection of bupivacaine with adrenaline in usual doses caused subsequent cardiac arrest, completely reversed after administration of 20% intravenous lipid emulsion. Early diagnosis of local anaesthetics toxicity and adequate cardiovascular resuscitation manoeuvres contribute to the favourable outcome.

  11. Offenders' Perceptions of House Arrest and Electronic Monitoring

    Science.gov (United States)

    Martin, Jamie S.; Hanrahan, Kate; Bowers, James H., Jr.

    2009-01-01

    This article reports on a study designed to examine the perceptions of house arrest (HA) and electronic monitoring (EM) among offenders who have recently experienced this criminal sentence. Data were gathered via a self-administered questionnaire and follow-up interviews with a sample of offenders. Our primary areas of interest were to assess (a)…

  12. Is Ward Experience in Resuscitation Effort Related to the Prognosis of Unexpected Cardiac Arrest?

    Directory of Open Access Journals (Sweden)

    Sen-Kuang Hou

    2007-09-01

    Conclusion: Hospital wards with more than 5 cardiac arrests per year have a better patient survival rate than those with fewer arrests. This is despite all ward staff receiving the same level of training.

  13. Age structure and feeding of the neotropical grasshopper Cornops aquaticum (Bruner) (Orthoptera: Acrididae) on water hyacinth.

    Science.gov (United States)

    Franceschini, M C; de Wysiecki, M L; Poi, A

    2013-08-01

    We aimed to evaluate the variation in the age structure of Cornops aquaticum (Bruner) population and its relation to the host plant biomass and the feeding of the different age classes of this grasshopper on the water hyacinth Eichhornia crassipes along 2 years, in a Paraná River floodplain lake (Chaco, Argentina). Individuals of C. aquaticum were captured with a 70-cm diameter sweep and separated in nymphs A (instars I and II), nymphs B (instars III to VI), adult females, and adult males; host plant biomass was sampled using a ring with a 0.30-m(2) diameter. Relative daily feeding of C. aquaticum population was calculated by multiplying the number of individuals captured per minute by the daily consumption by individual obtained in each age classes. We found that the age structure and the relative daily feeding of C. aquaticum varied between seasons and years. The highest values of grasshopper abundance, leaf biomass, and relative daily feeding of C. aquaticum population were observed in summer 2006. Plant biomass was directly correlated with nymph abundance and not correlated with adult abundance. Plant biomass available as refuge (leaves), food (laminas), and oviposition site (petioles) to C. aquaticum represented up to 62% of the total plant biomass. The results obtained in C. aquaticum show the importance of considering total plant biomass and plant biomass available for herbivores separately. Our study highlights the need to find an adequate method to estimate the density of C. aquaticum and other semiaquatic grasshoppers in the Paraná River floodplain involving different seasons, years, and water phases (rising and falling).

  14. Diverse and tunable electronic structures of single-layer metal phosphorus trichalcogenides for photocatalytic water splitting

    International Nuclear Information System (INIS)

    Liu, Jian; Li, Xi-Bo; Wang, Da; Liu, Li-Min; Lau, Woon-Ming; Peng, Ping

    2014-01-01

    The family of bulk metal phosphorus trichalcogenides (APX 3 , A = M II , M 0.5 I M 0.5 III ; X = S, Se; M I , M II , and M III represent Group-I, Group-II, and Group-III metals, respectively) has attracted great attentions because such materials not only own magnetic and ferroelectric properties, but also exhibit excellent properties in hydrogen storage and lithium battery because of the layered structures. Many layered materials have been exfoliated into two-dimensional (2D) materials, and they show distinct electronic properties compared with their bulks. Here we present a systematical study of single-layer metal phosphorus trichalcogenides by density functional theory calculations. The results show that the single layer metal phosphorus trichalcogenides have very low formation energies, which indicates that the exfoliation of single layer APX 3 should not be difficult. The family of single layer metal phosphorus trichalcogenides exhibits a large range of band gaps from 1.77 to 3.94 eV, and the electronic structures are greatly affected by the metal or the chalcogenide atoms. The calculated band edges of metal phosphorus trichalcogenides further reveal that single-layer ZnPSe 3 , CdPSe 3 , Ag 0.5 Sc 0.5 PSe 3 , and Ag 0.5 In 0.5 PX 3 (X = S and Se) have both suitable band gaps for visible-light driving and sufficient over-potentials for water splitting. More fascinatingly, single-layer Ag 0.5 Sc 0.5 PSe 3 is a direct band gap semiconductor, and the calculated optical absorption further convinces that such materials own outstanding properties for light absorption. Such results demonstrate that the single layer metal phosphorus trichalcogenides own high stability, versatile electronic properties, and high optical absorption, thus such materials have great chances to be high efficient photocatalysts for water-splitting

  15. Varying the charge of small cations in liquid water: Structural, transport, and thermodynamical properties

    Science.gov (United States)

    Martelli, Fausto; Vuilleumier, Rodolphe; Simonin, Jean-Pierre; Spezia, Riccardo

    2012-10-01

    In this work, we show how increasing the charge of small cations affects the structural, thermodynamical, and dynamical properties of these ions in liquid water. We have studied the case of lanthanoid and actinoid ions, for which we have recently developed accurate polarizable force fields, and the ionic radius is in the 0.995-1.250 Å range, and explored the valency range from 0 to 4+. We found that the ion charge strongly structures the neighboring water molecules and that, in this range of charges, the hydration enthalpies exhibit a quadratic dependence with respect to the charge, in line with the Born model. The diffusion process follows two main regimes: a hydrodynamical regime for neutral or low charges, and a dielectric friction regime for high charges in which the contraction of the ionic radius along the series of elements causes a decrease of the diffusion coefficient. This latter behavior can be qualitatively described by theoretical models, such as the Zwanzig and the solvated ion models. However, these models need be modified in order to obtain agreement with the observed behavior in the full charge range. We have thus modified the solvated ion model by introducing a dependence of the bare ion radius as a function of the ionic charge. Besides agreement between theory and simulation this modification allows one to obtain an empirical unified model. Thus, by analyzing the contributions to the drag coefficient from the viscous and the dielectric terms, we are able to explain the transition from a regime in which the effect of viscosity dominates to one in which dielectric friction governs the motion of ions with radii of ca. 1 Å.

  16. Linalool Induces Cell Cycle Arrest and Apoptosis in Leukemia Cells and Cervical Cancer Cells through CDKIs

    Directory of Open Access Journals (Sweden)

    Mei-Yin Chang

    2015-11-01

    Full Text Available Plantaginaceae, a popular traditional Chinese medicine, has long been used for treating various diseases from common cold to cancer. Linalool is one of the biologically active compounds that can be isolated from Plantaginaceae. Most of the commonly used cytotoxic anticancer drugs have been shown to induce apoptosis in susceptible tumor cells. However, the signaling pathway for apoptosis remains undefined. In this study, the cytotoxic effect of linalool on human cancer cell lines was investigated. Water-soluble tetrazolium salts (WST-1 based colorimetric cellular cytotoxicity assay, was used to test the cytotoxic ability of linalool against U937 and HeLa cells, and flow cytometry (FCM and genechip analysis were used to investigate the possible mechanism of apoptosis. These results demonstrated that linalool exhibited a good cytotoxic effect on U937 and HeLa cells, with the IC50 value of 2.59 and 11.02 μM, respectively, compared with 5-FU with values of 4.86 and 12.31 μM, respectively. After treating U937 cells with linalool for 6 h, we found an increased sub-G1 peak and a dose-dependent phenomenon, whereby these cells were arrested at the G0/G1 phase. Furthermore, by using genechip analysis, we observed that linalool can promote p53, p21, p27, p16, and p18 gene expression. Therefore, this study verified that linalool can arrest the cell cycle of U937 cells at the G0/G1 phase and can arrest the cell cycle of HeLa cells at the G2/M phase. Its mechanism facilitates the expression of the cyclin-dependent kinases inhibitors (CDKIs p53, p21, p27, p16, and p18, as well as the non-expression of cyclin-dependent kinases (CDKs activity.

  17. [Changes of bacterial community structure on reusing domestic sewage of Daoxianghujing Hotel to landscape water].

    Science.gov (United States)

    Zhu, Jing-nan; Wang, Xiao-dan; Zhai, Zhen-hua; Ma, Wen-lin; Li, Rong-qi; Wang, Xue-lian; Li, Yan-hong

    2010-05-01

    A 16S rDNA library was used to evaluate the bacterial diversity and identify dominant groups of bacteria in different treatment pools in the domestic sewage system of the Beijing Daoxianghujing Hotel. The results revealed that there were many types of bacteria in the hotel domestic sewage, and the bacterial Shannon-Weaver diversity index was 3.12. In addition, epsilon Proteobacteria was found to be the dominant group with the ratio of 32%. In addition, both the CFB phylum, Fusobacteria, gamma Proteobacteria and Firmicutes were also reached to 9%-15%. After treated with the reclaimed water station, the bacterial Shannon-Weaver diversity index was reduced to 2. 41 and beta Proteobacteria became the dominant group and occupied 73% of the total clones. However, following artificial wetland training, the bacterial Shannon-Weaver diversity index in the sample increased to 3.38, Actinobacteria arrived to 33% and became the most dominant group; Cyanobacteria reached to 26%, and was the second dominant group. But, the control sample comprised 38% Cyanobacteria, and mainly involved in Cyanobium, Synechoccus and Microcystis, with ratios of 47.1%, 17.6% and 8.8%, respectively. Some bacteria of Microcystis aenruginosa were also detected, which probably resulted in the light bloom finally. Therefore, the bacterial diversity and community structures changed in response to treatment of the hotel domestic sewage; there was no cyanobacteria bloom explosion in the treated water. This study will aid in investigation the changes of microbial ecology in different types of water and providing the useful information for enhancing the cyanobacteria blooms control from ecological angle.

  18. The porous carbon derived from water hyacinth with well-designed hierarchical structure for supercapacitors

    Science.gov (United States)

    Zheng, Kaiwen; Li, Yuanyuan; Zhu, Ming; Yu, Xi; Zhang, Mengyan; Shi, Ling; Cheng, Jue

    2017-10-01

    A hierarchical porous water hyacinth-derived carbon (WHC) is fabricated by pre-carbonization and KOH activation for supercapacitors. The physicochemical properties of WHC are researched by scanning electron microscopy (SEM), N2 adsorption-desorption measurements, X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The results indicate that WHC exhibits hierarchical porous structure and high specific surface area of 2276 m2/g. And the electrochemical properties of WHC are studied by cyclic voltammetry (CV), galvanostatic charge-discharge and electrochemical impedance spectroscopy (EIS) tests. In a three-electrode test system, WHC shows considerable specific capacitance of 344.9 F/g at a current density of 0.5 A/g, good rate performance with 225.8 F/g even at a current density of 30 A/g, and good cycle stability with 95% of the capacitance retention after 10000 cycles of charge-discharge at a current density of 5 A/g. Moreover, WHC cell delivers an energy density of 23.8 Wh/kg at 0.5 A/g and a power density of 15.7 kW/kg at 10 A/g. Thus, using water hyacinth as carbon source to fabricate supercapacitors electrodes is a promising approach for developing inexpensive, sustainable and high-performance carbon materials. Additionally, this study supports the sustainable development and the control of biological invasion.

  19. Therapeutic Hypothermia after In-Hospital Cardiac Arrest in Children.

    Science.gov (United States)

    Moler, Frank W; Silverstein, Faye S; Holubkov, Richard; Slomine, Beth S; Christensen, James R; Nadkarni, Vinay M; Meert, Kathleen L; Browning, Brittan; Pemberton, Victoria L; Page, Kent; Gildea, Marianne R; Scholefield, Barnaby R; Shankaran, Seetha; Hutchison, Jamie S; Berger, John T; Ofori-Amanfo, George; Newth, Christopher J L; Topjian, Alexis; Bennett, Kimberly S; Koch, Joshua D; Pham, Nga; Chanani, Nikhil K; Pineda, Jose A; Harrison, Rick; Dalton, Heidi J; Alten, Jeffrey; Schleien, Charles L; Goodman, Denise M; Zimmerman, Jerry J; Bhalala, Utpal S; Schwarz, Adam J; Porter, Melissa B; Shah, Samir; Fink, Ericka L; McQuillen, Patrick; Wu, Theodore; Skellett, Sophie; Thomas, Neal J; Nowak, Jeffrey E; Baines, Paul B; Pappachan, John; Mathur, Mudit; Lloyd, Eric; van der Jagt, Elise W; Dobyns, Emily L; Meyer, Michael T; Sanders, Ronald C; Clark, Amy E; Dean, J Michael

    2017-01-26

    Targeted temperature management is recommended for comatose adults and children after out-of-hospital cardiac arrest; however, data on temperature management after in-hospital cardiac arrest are limited. In a trial conducted at 37 children's hospitals, we compared two temperature interventions in children who had had in-hospital cardiac arrest. Within 6 hours after the return of circulation, comatose children older than 48 hours and younger than 18 years of age were randomly assigned to therapeutic hypothermia (target temperature, 33.0°C) or therapeutic normothermia (target temperature, 36.8°C). The primary efficacy outcome, survival at 12 months after cardiac arrest with a score of 70 or higher on the Vineland Adaptive Behavior Scales, second edition (VABS-II, on which scores range from 20 to 160, with higher scores indicating better function), was evaluated among patients who had had a VABS-II score of at least 70 before the cardiac arrest. The trial was terminated because of futility after 329 patients had undergone randomization. Among the 257 patients who had a VABS-II score of at least 70 before cardiac arrest and who could be evaluated, the rate of the primary efficacy outcome did not differ significantly between the hypothermia group and the normothermia group (36% [48 of 133 patients] and 39% [48 of 124 patients], respectively; relative risk, 0.92; 95% confidence interval [CI], 0.67 to 1.27; P=0.63). Among 317 patients who could be evaluated for change in neurobehavioral function, the change in VABS-II score from baseline to 12 months did not differ significantly between the groups (P=0.70). Among 327 patients who could be evaluated for 1-year survival, the rate of 1-year survival did not differ significantly between the hypothermia group and the normothermia group (49% [81 of 166 patients] and 46% [74 of 161 patients], respectively; relative risk, 1.07; 95% CI, 0.85 to 1.34; P=0.56). The incidences of blood-product use, infection, and serious adverse

  20. Income inequality, drug-related arrests, and the health of people who inject drugs: Reflections on seventeen years of research

    OpenAIRE

    Friedman, Samuel R.; Tempalski, Barbara; Brady, Joanne E.; West, Brooke S.; Pouget, Enrique R.; Williams, Leslie D.; Des Jarlais, Don C.; Cooper, Hannah L.F.

    2016-01-01

    This paper reviews and then discusses selected findings from a seventeen year study about the population prevalence of people who inject drugs (PWID) and of HIV prevalence and mortality among PWID in 96 large US metropolitan areas. Unlike most research, this study was conducted with the metropolitan area as the level of analysis. It found that metropolitan area measures of income inequality and of structural racism predicted all of these outcomes, and that rates of arrest for heroin and/or co...