Nutritional components of the sea cucumber Holothuria scabra

Directory of Open Access Journals (Sweden)

Morakot Sroyraya

2017-03-01

Full Text Available Background: Holothuria scabrais one of the most commercially important species found in the Pacific region. The sea cucumber extracts have been widely reported to have beneficial health effects.The aim of this study was to determine the nutritional compositions of H. scabra, and compare its important nutritional contents with that of other species.Methods:The sea cucumbers were dissected, sliced into small pieces,and then freeze-dried. The nutritional compositions, including proximate composition, amino acids, fatty acids,collagen, GABA, Vitamin A, C, and E of the whole body and body wall of H. scabra,were analyzed.Results:H. scabra contained a high quantity of protein (22.50% in whole body and 55.18% in body wall and very low lipids (1.55% in whole body and 1.02% in body wall. The three most abundant amino acids found in both the whole body and body wall were glycine, glutamic acid, and proline. The main fatty acids found in the whole body were stearic acid and nervonic acid, and in the body wall were arachidonic acid and stearic acid. The whole body and body wall also contained high levels of essential amino acids, essential fatty acids, and collagen, in addition to moderate amounts of vitamin E and low amounts of GABA and vitamin C.Conclusions:The sea cucumber, H. scabra, contained high quantity of protein and very low lipid. It containedhigh essential amino acids, essential fatty acids, nervonic and arachidonic acids, and collagen, which also contained GABA, vitamin C, and vitamin E.

Sarcocysts of an unidentified species of Sarcocystis in the sea otter (Enhydra lutris)

Science.gov (United States)

Dubey, J.P.; Lindsay, D.S.; Rosenthal, B.M.; Thomas, N.J.

2003-01-01

The number of Sarcocystis species that infect sea otters (Enhydra lutris) is unknown. Sea otter tissues were recently shown to harbor sarcocysts of S. neurona and of unidentified species of Sarcocystis. Whereas sarcocysts of S. neurona have walls 1a??3 I?m thick with type 9 villar protrusions, ultrastructure of a distinct thin-walled sarcocyst (0.5a??0.7 I?m thick) lacking villar protrusions, but instead exhibiting minute type 1 undulations on the sarcocyst wall, is described in this report. Parasites characterized from a sea otter infection were inferred to be related to, but distinct from, other species belonging to Sarcocystis, based on sequencing and phylogenetic analysis of a portion of the beta subunit of the plastid-encoded RNA polymerase gene.

Studies of the reproductive biology of deep sea megabenthos VIII. Biochemical and calorific content of the reproductive organs of deep sea holothurians

International Nuclear Information System (INIS)

Tyler, P.A.; Walker, M.

1987-01-01

The data for protein, lipid, carbohydrate and ash content of the ovary, testes, gut and body wall of a variety of deep sea holothurians are presented. The dominant biochemical is insoluble protein in all tissues followed by lipid in the ovary. The ash content was lowest in the gonads and highest in the body wall of most species. The mean calorific content of the species studied is 25.08Jmg -1 thus representing a significant energy store in the deep sea. The data suggest active metabolic pathways in these species which may pass radionuclides to the developing gametes and after spawning to dispersal in deep waters. (author)

Characterization and phylogenetic analysis of lectin gene cDNA isolated from sea cucumber ( Apostichopus japonicus) body wall

Science.gov (United States)

Xue, Zhuang; Li, Hui; Liu, Yang; Zhou, Wei; Sun, Jing; Wang, Xiuli

2017-12-01

As a `living fossil' of species origin and `rich treasure' of food and nutrition development, sea cucumber has received a lot of attentions from researchers. The cDNA library construction and EST sequencing of blood had been conducted previously in our lab. The bioinformatic analysis provided a gene fragment which is highly homologous with the genes of lectin family, named AjL ( Apostichopus japonicus lectin). To characterize and determine the phylogeny of AjL genes in early evolution, we isolated a full-length cDNA of lectin gene from the body wall of A. japonicus. The open reading frame of this gene contained 489 bp and encoded a 163 amino acids secretory protein being homologous to lectins of mammals and aquatic organisms. The deduced protein included a lectin-like domain. SDS-PAGE analysis showed that AjL migrated as a specific band (about 36.09 kDa under reducing), and agglutinated against rabbit red blood cells. AjL was similar to chain A of CEL-IV in space structure. We predicted that AjL may play the same role of CEL-IV. Our results suggested that more than one lectin gene functioned in sea cucumber and most of other species, which was fused by uncertain sequences during the evolution and encoded different proteins with diverse functions. Our findings provided the insights into the function and characteristics of lectin genes invertebrates. The results will also be helpful for the identification and structural, functional, and evolutionary analyses of lectin genes.

Changes in collagenous tissue microstructures and distributions of cathepsin L in body wall of autolytic sea cucumber (Stichopus japonicus).

Science.gov (United States)

Liu, Yu-Xin; Zhou, Da-Yong; Ma, Dong-Dong; Liu, Yan-Fei; Li, Dong-Mei; Dong, Xiu-Ping; Tan, Ming-Qian; Du, Ming; Zhu, Bei-Wei

2016-12-01

The autolysis of sea cucumber (Stichopus japonicus) was induced by ultraviolet (UV) irradiation, and the changes of microstructures of collagenous tissues and distributions of cathepsin L were investigated using histological and histochemical techniques. Intact collagen fibers in fresh S. japonicus dermis were disaggregated into collagen fibrils after UV stimuli. Cathepsin L was identified inside the surface of vacuoles in the fresh S. japonicus dermis cells. After the UV stimuli, the membranes of vacuoles and cells were fused together, and cathepsin L was released from cells and diffused into tissues. The density of cathepsin L was positively correlated with the speed and degree of autolysis in different layers of body wall. Our results revealed that lysosomal cathepsin L was released from cells in response to UV stimuli, which contacts and degrades the extracellular substrates such as collagen fibers, and thus participates in the autolysis of S. japonicus. Copyright © 2016 Elsevier Ltd. All rights reserved.

A southern North Sea Miocene dinoflagellate cyst zonation

NARCIS (Netherlands)

Munsterman, D.K.; Brinkhuis, H.

2004-01-01

An integrated stratigraphical analysis emphasizing organic-walled dinoflagellate cyst (dinocyst) distribution has been carried out on multiple boreholes penetrating the Miocene in the subsurface of the Netherlands (southern North Sea Basin). The bulk of the investigated successions is attributed to

Wave trapping by dual porous barriers near a wall in the presence of bottom undulation

Science.gov (United States)

Kaligatla, R. B.; Manisha; Sahoo, T.

2017-09-01

Trapping of oblique surface gravity waves by dual porous barriers near a wall is studied in the presence of step type varying bottom bed that is connected on both sides by water of uniform depths. The porous barriers are assumed to be fixed at a certain distance in front of a vertical rigid wall. Using linear water wave theory and Darcy's law for flow past porous structure, the physical problem is converted into a boundary value problem. Using eigenfunction expansion in the uniform bottom bed region and modified mild-slope equation in the varying bottom bed region, the mathematical problem is handled for solution. Moreover, certain jump conditions are used to account for mass conservation at slope discontinuities in the bottom bed profile. To understand the effect of dual porous barriers in creating tranquility zone and minimum load on the sea wall, reflection coefficient, wave forces acting on the barrier and the wall, and surface wave elevation are computed and analyzed for different values of depth ratio, porous-effect parameter, incident wave angle, gap between the barriers and wall and slope length of undulated bottom. The study reveals that with moderate porosity and suitable gap between barriers and sea wall, using dual barriers an effective wave trapping system can be developed which will exert less wave force on the barriers and the rigid wall. The proposed wave trapping system is likely to be of immense help for protecting various facilities/ infrastructures in coastal environment.

Wave Trapping by Dual Porous Barriers Near a Wall in the Presence of Bottom Undulation

Institute of Scientific and Technical Information of China (English)

R.B. Kaligatla; Manisha; T. Sahoo

2017-01-01

Trapping of oblique surface gravity waves by dual porous barriers near a wall is studied in the presence of step type varying bottom bed that is connected on both sides by water of uniform depths. The porous barriers are assumed to be fixed at a certain distance in front of a vertical rigid wall. Using linear water wave theory and Darcy's law for flow past porous structure, the physical problem is converted into a boundary value problem. Using eigenfunction expansion in the uniform bottom bed region and modified mild-slope equation in the varying bottom bed region, the mathematical problem is handled for solution. Moreover, certain jump conditions are used to account for mass conservation at slope discontinuities in the bottom bed profile. To understand the effect of dual porous barriers in creating tranquility zone and minimum load on the sea wall, reflection coefficient, wave forces acting on the barrier and the wall, and surface wave elevation are computed and analyzed for different values of depth ratio, porous-effect parameter, incident wave angle, gap between the barriers and wall and slope length of undulated bottom. The study reveals that with moderate porosity and suitable gap between barriers and sea wall, using dual barriers an effective wave trapping system can be developed which will exert less wave force on the barriers and the rigid wall. The proposed wave trapping system is likely to be of immense help for protecting various facilities/ infrastructures in coastal environment.

Characterization and comparison of proteomes of albino sea cucumber Apostichopus japonicus (Selenka) by iTRAQ analysis.

Science.gov (United States)

Xia, Chang-Ge; Zhang, Dijun; Ma, Chengnv; Zhou, Jun; He, Shan; Su, Xiu-Rong

2016-04-01

Sea cucumber is a commercially important marine organism in China. Of the different colored varieties sold in China, albino sea cucumber has the greatest appeal among consumers. Identification of factors contributing to albinism in sea cucumber is therefore likely to provide a scientific basis for improving the cultivability of these strains. In this study, two-dimensional liquid chromatography-tandem mass spectrometry coupled with isobaric tags for relative and absolute quantification labeling was used for the first time to quantitatively define the proteome of sea cucumbers and reveal proteomic characteristics unique to albino sea cucumbers. A total of 549 proteins were identified and quantified in albino sea cucumber and the functional annotations of 485 proteins have been exhibited based on COG database. Compared with green sea cucumber, 12 proteins were identified as differentially expressed in the intestine and 16 proteins in the body wall of albino sea cucumber. Among them, 5 proteins were up-regulated in the intestine and 8 proteins were down-regulated in body wall. Gene ontology annotations of these differentially expressed proteins consisted mostly of 'biological process'. The large number of differentially expressed proteins identified here should be highly useful in further elucidating the mechanisms underlying albinism in sea cucumber. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effects of dietary lead on growth, bioaccumulation and antioxidant capacity in sea cucumber, Apostichopus japonicus.

Science.gov (United States)

Wang, Jing; Ren, Tongjun; Han, Yuzhe; Zhao, Yang; Liao, Mingling; Wang, Fuqiang; Jiang, Zhiqiang

2015-09-01

Three different diets amended with lead nitrate [Pb(NO3)2] (100, 500 and 1000mg Pb/kg dry weight) and a Pb-free control diet (1.03mg Pb/kg dry weight) were fed to sea cucumber (Apostichopus japonicus) for 30 days. The patterns of Pb accumulation over time were determined in various tissues (body wall, intestine and respiratory tree), as well as growth performance and antioxidant enzymes activities. Pb accumulation in body wall and intestine increased with time in all dietary Pb treatments. When fed the highest Pb diet, the body wall exhibited the greatest Pb burden (16.37mg Pb/kg tissue wet weight), while Pb content in the intestine (2.68mg Pb/kg tissue wet weight) and the respiratory tree (1.78mg Pb/kg tissue wet weight) were lower than Pb content in the body wall by day 30. The body weight gain (BWG), specific growth rate (SGR) and survival rate (SR) had not been affected by 30 days oral administration of Pb supplemented diet. However, the antioxidant enzymes activities [superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)] of test groups were lower than control group in body wall and malondialdehyde (MDA) concentration in the body wall was opposite after 30 days in sea cucumbers. In summary, this work reports toxic effects in sea cucumber, A. japonicus, after dietary exposure to Pb. Copyright © 2015 Elsevier B.V. All rights reserved.

Impact of sea spray on the Yellow and East China Seas thermal structure during the passage of Typhoon Rammasun (2002)

Science.gov (United States)

Zhang, Lianxin; Zhang, Xuefeng; Chu, P. C.; Guan, Changlong; Fu, Hongli; Chao, Guofang; Han, Guijun; Li, Wei

2017-10-01

Strong winds lead to large amounts of sea spray in the lowest part of the atmospheric boundary layer. The spray droplets affect the air-sea heat fluxes due to their evaporation and the momentum due to the change of sea surface, and in turn change the upper ocean thermal structure. In this study, impact of sea spray on upper ocean temperatures in the Yellow and East China Seas (YES) during typhoon Rammasun's passage is investigated using the POMgcs ocean model with a sea spray parameterization scheme, in which the sea spray-induced heat fluxes are based on an improved Fairall's sea spray heat fluxes algorithm, and the sea spray-induced momentum fluxes are derived from an improved COARE version 2.6 bulk model. The distribution of the sea spray mediated turbulent fluxes was primarily located at Rammasun eye-wall region, in accord with the maximal wind speeds regions. When Rammasun enters the Yellow sea, the sea spray mediated latent (sensible) heat flux maximum is enhanced by 26% (13.5%) compared to that of the interfacial latent (sensible) heat flux. The maximum of the total air-sea momentum fluxes is enhanced by 43% compared to the counterpart of the interfacial momentum flux. Furthermore, the sea spray plays a key role in enhancing the intensity of the typhoon-induced "cold suction" and "heat pump" processes. When the effect of sea spray is considered, the maximum of the sea surface cooling in the right side of Rammasun's track is increased by 0.5°C, which is closer to the available satellite observations.

Molecular cloning and functional characterization of cathepsin D from sea cucumber Apostichopus japonicus.

Science.gov (United States)

Yu, Cuiping; Cha, Yue; Wu, Fan; Xu, Xianbing; Qin, Lei; Du, Ming

2017-11-01

Cathepsin D (CTSD, EC 3.4.23.5) belongs to aspartic protease family, which is located in lysosomes and is distributed in diverse tissues and cells. CTSD has a wide variety of physiological functions, owing to its proteolytic activity in degradating proteins and peptides. In the current study, the full length cDNA of sea cucumber (Apostichopus japonicus) cathepsin D (AjCTSD) was firstly cloned, then the association between AjCTSD and sea cucumber autolysis was investigated. The full length cDNA of AjCTSD was 2896 bp, with an open reading frame (ORF) for 391 amino acids. AjCTSD was widely expressed in body wall, muscle and intestine; the expression level was the highest in intestine, followed by muscle and body wall. Compared to fresh tissues, AjCTSD expression levels were significantly increased in all examined autolytic tissues. The purified recombinant AjCTSD promoted the degradation of sea cucumber muscle. In conclusion, AjCTSD contributed to sea cucumber muscle autolysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biological activities and biomedical potential of sea cucumber (Stichopus japonicus: a review

Directory of Open Access Journals (Sweden)

Gun-Woo Oh

2017-11-01

Full Text Available Abstract Members of the phylum Echinodermata, commonly known as echinoderms, are exclusively marine invertebrates. Among the Echinodermata, sea cucumber belongs to the family Holothuroidea. The sea cucumber Stichopus (Apostichous japonicus (Selenka is an invertebrate animal inhabiting the coastal sea around Korean, Japan, China, and Russia. Sea cucumber has a significant commercial value, because it contains valuable nutrients such as vitamins and minerals. They possess a number of distinctive biologically and pharmacologically important compounds. In particular, the body wall of sea cucumber is a major edible part. It consists of peptide, collagen, gelatin, polysaccharide, and saponin, which possess several biological activities such as anti-cancer, anti-coagulation, anti-oxidation, and anti-osteoclastogenesis. Furthermore, the regenerative capacity of sea cucumber makes it a medically important organism. This review presents the various biological activities and biomedical potential of sea cucumber S. japonicus.

Two observations on the wave approach to SEA : Keynote Lecture

OpenAIRE

Finnveden, Svante

2007-01-01

First, it is shown that the use of SEA coupling factors derived for the coupling of semi infinite systems is consistent with coupling power proportionality. This demonstration is axiomatic, relying on a set of postulates. It is useful in teaching SEA, as it illustrates concepts and assumptions commonly made. It might be useful for research aiming for a better set of postulates upon which a statistical energy method can be built. Second, the wave motion in double walls is investigated. A new S...

Design for tsunami barrier wall based on numerical analyses of tsunami inundation at Shimane Nuclear Power Plant

International Nuclear Information System (INIS)

Kiyoshige, Naoya; Yoshitsugu, Shinich; Kawahara, Kazufumi; Ookubo, Yoshimi; Nishihata, Takeshi; Ino, Hitoshi; Kotoura, Tsuyoshi

2014-01-01

The conventional tsunami assessment of the active fault beneath the Japan sea in front of the Shimane nuclear power plant and the earthquake feared to happen at the eastern margin of the Japan sea does not expect a huge tsunami as to be assumed on the Pacific sea coast. Hence, the huge tsunami observed at the power plant located near the source of the Tohoku Pacific sea earthquake tsunami whose run-up height reached TP+15m is regarded as the level 2 tsunami for the Shimane nuclear power plant and planned to construct the tsunami barrier walls to endure the supposed level 2 tsunami. In this study, the setting of the Level 2 tsunami by using the numerical analysis based on the non-linear shallow water theory and evaluation for the design tsunami wave pressure exerted on the counter measures by using CADMAS-SURF/3D are discussed. The designed tsunami barrier walls which are suitable to the power plant feasibility and decided from the design tsunami wave pressure distribution based on Tanimoto's formulae and standard earthquake ground motion Ss are also addressed. (author)

Development of sea water pipe thickness measurement technique

International Nuclear Information System (INIS)

Morimoto, Kazuo; Wakayama, Seiichi; Takeuchi, Iwao; Masamori, Sigero; Yamasita, Takesi.

1995-01-01

In nuclear and thermal power plants, wall wear of sea water pipes is reported to occur in the inner surface due to corrosion and erosion. From the viewpoint of improving the equipments reliability, it is desirable that wall thickness should be measured from the outer surface of the pipe during operation. In the conventional method, paint on the outer surface of the pipe was locally removed at each point of a 20 by 50 mm grid, and inspection was carried out at these spots. However, this method had some problems, such as (1) it was necessary to replace the paint, and (2) it was difficult to obtain the precise distribution of wall thickness. Therefore, we have developed a wall thickness measuring system which has the following features. (1) It is possible to perform inspection from the outer surface without removing paint during operation. (2) It is possible to measure the distribution of wall thickness and display it as color contour map simultaneously. (3) The work of inspectors can be alleviated by the automatic recording of measured data. (author)

2D speckle tracking echocardiography of the right ventricle free wall in SCUBA divers after single open sea dive.

Science.gov (United States)

Susilovic-Grabovac, Zora; Obad, Ante; Duplančić, Darko; Banić, Ivana; Brusoni, Denise; Agostoni, Piergiuseppe; Vuković, Ivica; Dujic, Zeljko; Bakovic, Darija

2018-03-01

The presence of circulating gas bubbles and their influence on pulmonary and right heart hemodynamics was reported after uncomplicated self-contained underwater breathing apparatus (SCUBA) dive(s). Improvements in cardiac imaging have recently focused great attention on the right ventricle (RV). The aim of our study was to evaluate possible effects of a single air SCUBA dive on RV function using 2D speckle tracking echocardiography in healthy divers after single open sea dive to 18 meters of seawater, followed by bottom stay of 47 minutes with a direct ascent to the surface. Twelve experienced male divers (age 39.5 ± 10.5 years) participated in the study. Echocardiographic assessment of the right ventricular function (free wall 2 D strain, tricuspid annular planes systolic excursion [TAPSE], lateral tricuspid annular peak systolic velocity [RV s`] and fractional area change [FAC]) was performed directly prior to and 30, 60, 90 and 120 minutes after surfacing. Two-dimensional strain of all three segments of free right ventricular wall showed a significant increase in longitudinal shortening in post-dive period for maximally 26% (basal), 15.4% (mid) and 16.3% (apical) as well as TAPSE (11.6%), RV FAC (19.2%), RV S` (12.7%) suggesting a rise in systolic function of right heart. Mean pulmonary arterial pressure (mean PAP) increased post-dive from 13.3 mmHg to maximally 23.5 mmHg (P = .002), indicating increased RV afterload. Our results demonstrated that single dive with significant bubble load lead to increase in systolic function and longitudinal strain of the right heart in parallel with increase in mean PAP. © 2017 John Wiley & Sons Australia, Ltd.

Sulphide mineralization and wall-rock alteration in ophiolites and modern oceanic spreading centres

Science.gov (United States)

Koski, R.A.

1983-01-01

Massive and stockwork Fe-Cu-Zn (Cyprus type) sulphide deposits in the upper parts of ophiolite complexes represent hydrothermal mineralization at ancient accretionary plate boundaries. These deposits are probable metallogenic analogues of the polymetallic sulphide deposits recently discovered along modern oceanic spreading centres. Genetic models for these deposits suggest that mineralization results from large-scale circulation of sea-water through basaltic basement along the tectonically active axis of spreading, a zone of high heat flow. The high geothermal gradient above 1 to 2 km deep magma chambers emplaced below the ridge axis drives the convective circulation cell. Cold oxidizing sea-water penetrating the crust on the ridge flanks becomes heated and evolves into a highly reduced somewhat acidic hydrothermal solvent during interaction with basaltic wall-rock. Depending on the temperature and water/rock ratio, this fluid is capable of leaching and transporting iron, manganese, and base metals; dissolved sea-water sulphate is reduced to sulphide. At the ridge axis, the buoyant hydrothermal fluid rises through permeable wall-rocks, and fluid flow may be focussed along deep-seated fractures related to extensional tectonic processes. Metal sulphides are precipitated along channelways as the ascending fluid undergoes adiabatic expansion and then further cooling during mixing with ambient sub-sea-floor water. Vigorous fluid flow results in venting of reduced fluid at the sea-floor/sea-water interface and deposition of massive sulphide. A comparison of sulphide mineralization and wall-rock alteration in ancient and modern spreading centre environments supports this genetic concept. Massive sulphide deposits in ophiolites generally occur in clusters of closely spaced (stacked sequences of pillow basalt and sheet flows, the sea-floor underlying numerous deposits in Guaymas Basin consists of diatomaceous ooze and terrigenous clastic sediment that is intruded by diabase

Wave Loading and Overtopping on Vertical Wall Breakwaters in Multidirectional Breaking Seas

DEFF Research Database (Denmark)

Kofoed, Jens Peter; Grønbech, J.; Hald, Tue

1998-01-01

The present paper concerns the results and findings of a physical study on wave impacts on vertical caisson breakwaters situated in irregular, multidirectional breaking seas. The study has taken place as part of the framework programme "Dynamics of Structures" financially supported by the Danish...

Ultraviolet-Ray-Induced Sea Cucumber (Stichopus japonicus) Melting Is Mediated by the Caspase-Dependent Mitochondrial Apoptotic Pathway.

Science.gov (United States)

Su, Li; Yang, Jing-Feng; Fu, Xi; Dong, Liang; Zhou, Da-Yong; Sun, Li-Ming; Gong, Zhenwei

2018-01-10

Sea cucumber body-wall melting occurs under certain circumstances. We have shown that apoptosis but not autolysis plays a critical role in the initial stage. However, it is still unclear how apoptosis is triggered in this process. In this study, we examined the levels of reactive oxygen species (ROS), the levels of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X (Bax) proteins, the depolarization of mitochondrial transmembrane potentials, and cytochrome c (Cyt c) release during sea cucumber melting induced by ultraviolet (UV) exposure. We also investigated the contribution of caspase in this process by injecting a pan-caspase inhibitor. Our data showed that UV exposure stimulates ROS production, dysfunction of mitochondria, and the release of Cyt c in sea cucumber coelomic fluid cells and body walls. We found a decrease of Bcl-2 and increase of Bax in the mitochondria after UV exposure. We also demonstrated that these changes are associated with elevated caspase-9 and -3 activity. Finally, our data showed that the inhibition of caspases-9 and -3 using an inhibitor suppresses UV-induced sea cucumber melting. These results suggest that apoptosis during sea cucumber melting is mediated by mitochondrial dysfunction and follows the activation of the caspase-signaling pathway. This study presents a novel insight into the mechanism of sea cucumber melting.

Wave Forces and Overtopping on Crown Walls of Rubble Mound Breakwaters

DEFF Research Database (Denmark)

Pedersen, Jan

The scientific progress of our understanding of the interaction between coastal structures and the sea has greatly improved in the recent years. The present state of knowledge includes structural and financial optimization of the structures based on reliability evaluations. The first requirement....... The stability of crown wall structures has also been investigated and a new methodology for the evaluation of the geodynamic response of the foundation is presented....

Localization and chiral symmetry in 2+1 flavor domain wall QCD

Energy Technology Data Exchange (ETDEWEB)

David J. Antonio; Kenneth C. Bowler; Peter A. Boyle; Norman H. Christ; Michael A. Clark; Saul D. Cohen; Chris Dawson; Alistair Hart; Balint Joó; Chulwoo Jung; Richard D. Kenway; Shu Li; Meifeng Lin; Robert D. Mawhinney; Christopher M. Maynard; Shigemi Ohta; Robert J. Tweedie; Azusa Yamaguchi

2008-01-01

We present results for the dependence of the residual mass of domain wall fermions (DWF) on the size of the fifth dimension and its relation to the density and localization properties of low-lying eigenvectors of the corresponding hermitian Wilson Dirac operator relevant to simulations of 2+1 flavor domain wall QCD. Using the DBW2 and Iwasaki gauge actions, we generate ensembles of configurations with a $16^3\\times 32$ space-time volume and an extent of 8 in the fifth dimension for the sea quarks. We demonstrate the existence of a regime where the degree of locality, the size of chiral symmetry breaking and the rate of topology change can be acceptable for inverse lattice spacings $a^{-1} \\ge 1.6$ GeV.

Hemolytic and cytotoxic properties of saponin purified from Holothuria leucospilota sea cucumber.

Science.gov (United States)

Soltani, Mozhgan; Parivar, Kazem; Baharara, Javad; Kerachian, Mohammad Amin; Asili, Javad

2014-10-01

Holothuroids (sea cucumbers) are members of the phylum echinodermata, which produce saponins. Saponins exhibit a wide spectrum of pharmacological and biological activities. In this study, we isolated the crude saponins from the body wall of the dominant Iranian species of sea cucumber, Holothuria leucospilota (H. leucospilota). The purpose of this study was to confirm the presence of saponins in the Persian Gulf H. leucospilota and study the hemolytic and cytotoxic activities of these compounds. The body wall of sea cucumber was dried and powdered and the crude saponins were isolated using various solvents. The crude saponins were further purified by column chromatography using HP-20 resin. The foam test, Thin Layer Chromatography (TLC), hemolytic assay, and Fourier Transform Infrared Spectroscopy (FTIR) confirmed the presence of saponins. Cytotoxicity was analyzed using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay on A549 cells, a human lung cancer cell line. The foam test, hemolytic assay, and TLC supported the presence of saponin compounds in the 80% ethanol fraction of H. leucospilota. The infrared (IR) spectrum of the extract showed hydroxyl (-OH), alkyl (C-H), ether (C-O) and ester (-C=O) absorption characteristic of teriterpenoid saponins. The C-O-C absorption indicated glycoside linkages to the sapogenins. The crude saponin extracted from sea cucumber was cytotoxic to A549 cells. The 80% ethanol fraction of saponin isolated from H. leucospilota exhibited hemolytic activity and offers promise as an anti-cancer candidate.

Effects of heat treatment on the gel properties of the body wall of sea cucumber (Apostichopus japonicus).

Science.gov (United States)

Zhang, Kai; Hou, Hu; Bu, Lin; Li, Bafang; Xue, Changhu; Peng, Zhe; Su, Shiwei

2017-03-01

The sensory texture of sea cucumber ( Apostichopus japonicus ) was dramatically affected by heat treatment. In this study, sea cucumbers were heated under different thermal conditions (HSC), and divided into five groups (HSC-80, HSC-90, HSC-100, HSC-110, and HSC-120) according to the heating temperature (from 80 to 120 °C). The changes in texture, moisture, gel structure, and biochemical parameters of the HSC were investigated. With increasing heating time (from 10 to 80 min), the hardness and gel structure changed slightly, and the water activity decreased as the proportion of T 21 increased by 133.33, 55.56, and 59.09% in the HSC-80, HSC-90, and HSC-100 groups, respectively. This indicated that moderate heating conditions (below 100 °C) caused gelation of sea cucumbers in HSC-80, HSC-90, and HSC-100 groups. However, as the water activity increased, the hardness declined rapidly by 2.56 and 2.7% in the HSC-110 and HSC-120 groups, with heating time increased from 10 to 80 min. Meanwhile, free hydroxyproline and ammonia nitrogen contents increased by 81.24 and 63.16% in the HSC-110 group; and by 63.09 and 54.99% in the HSC-120 group, as the gel structure of the sea cucumbers decomposed in these two groups. These results demonstrated that, severe heat treatment (above 100 °C) destroyed the chemical bonds, triggered the disintegration of collagen fibers and the gel structure of sea cucumbers, and transformed the migration and distribution of moisture, finally causing the deterioration of the sensory texture of the sea cucumbers.

Method of decommissioning nuclear reactor building by utilizing sea water buyoancy

International Nuclear Information System (INIS)

Iwashima, Sumio; Ogoshi, Shigeru; Kobari, Shin-ichi.

1989-01-01

Upon dismantling nuclear reactor buildings, peripheral yards are excavated and channels leading to sea shore are formed. Since the outer walls of the reactor buildings are made of iron-reinforced concretes, the opening poritons are grouted with concretes to attain a tightly such closed structure that radioactive wastes, etc. in the inside are not flown out upon reactor discommisioning. Peripheral buildings at relatively low level of radiation contaminations are dismantled and withdrawn. The fundations of the nuclear reactor buildings were dug out and jacked to separate base rocks and the reactor buildings. Then, sea water is introduced into the water channels to entirely float up the buildings. A water gate is disposed in the water channel on the side of sea shore to control the level of sea water. The buildings are moved and guided to the sea shore and towed to a site optimum as a permanent storage area and then burried in that place. The operation period for the discommissioning work can greatly be shortened and the radiation dose and the amount of the wastes can be reduced. (T.M.)

Kajian Konsep Kebijakan Infrastruktur Strategis untuk Pengendali Banjir Jakarta (Studi Kasus Giant Sea Wall dan Multi Purpose Deep Tunnel

Directory of Open Access Journals (Sweden)

Agung Wiyono

2016-04-01

Full Text Available Floods is a-must to be faced agenda by the government. However, the development of flood control infrastructure has not overcome floods in Jakarta. This study discusses the concept of policy plans and flood management infrastructure of sea wall and deep tunnels, simulation of decision-making in organizations with public policy theory: The Garbage Can a Model of Organizational Choice. Using comparative study, authors compare both infrastructure in the technical aspects, economic, environmental, social, and political, through qualitative and quantitative approaches to determine the most influential aspects. Analysis processed by the Analytical Hierarchy Process, Expert Choice and SPSS. The results showed difference in the consideration of the decision-making infrastructure. From the simulation of both types of infrastructure elections by using AHP, Expert Choice questionnaire and analysis, selected infrastructure is deep tunnel. In the analysis appears that the political aspect is regarded as the most influential aspect in decision making infrastructure. Which is not appropriate when a solution is needed to solve technical issues but politics was the main consideration and make solution becomes less relevant. This is proved by the simulation model of decision-making with a Garbage Can Theory of Organizational Choice models, where the simulation results show that the obtained solution for their supervision more than the obtained solution for their joint resolution.

Sea level trends in South East Asian Seas (SEAS)

Science.gov (United States)

Strassburg, M. W.; Hamlington, B. D.; Leben, R. R.; Manurung, P.; Lumban Gaol, J.; Nababan, B.; Vignudelli, S.; Kim, K.-Y.

2014-10-01

Southeast Asian Seas (SEAS) span the largest archipelago in the global ocean and provide a complex oceanic pathway connecting the Pacific and Indian Oceans. The SEAS regional sea level trends are some of the highest observed in the modern satellite altimeter record that now spans almost two decades. Initial comparisons of global sea level reconstructions find that 17 year sea level trends over the past 60 years exhibit good agreement in areas and at times of strong signal to noise associated decadal variability forced by low frequency variations in Pacific trade winds. The SEAS region exhibits sea level trends that vary dramatically over the studied time period. This historical variation suggests that the strong regional sea level trends observed during the modern satellite altimeter record will abate as trade winds fluctuate on decadal and longer time scales. Furthermore, after removing the contribution of the Pacific Decadal Oscillation (PDO) to sea level trends in the past twenty years, the rate of sea level rise is greatly reduced in the SEAS region. As a result of the influence of the PDO, the SEAS regional sea level trends during 2010s and 2020s are likely to be less than the global mean sea level (GMSL) trend if the observed oscillations in wind forcing and sea level persist. Nevertheless, long-term sea level trends in the SEAS will continue to be affected by GMSL rise occurring now and in the future.

Osmotic relations of the coelomic fluid and body wall tissues in Arenicola marina subjected to salinity change

DEFF Research Database (Denmark)

Weber, Roy E.; Spaargaren, D.H.

1979-01-01

nitrogenous organic molecules (ninhydrin-positive substances, NPS) in the body wall tissues and in the coelomic fluid of specimens of Arenicola in response to sudden changes in salinity. The coelomic solutes consist almost entirely of electrolytes and the osmotic contribution of NPS is essentially negligible....... In the body wall extracts, however, NPS accounts for at least one third of the osmotic concentration and for most of the substantial non-electrolyte fraction. There is no evidence from coelomic NPS measurements for extrusion of cellular amino acids during adaptation to lowered salinity. In diluted sea water...

Hemolytic and Cytotoxic Properties of Saponin Purified from Holothuria leucospilota Sea Cucumber

Directory of Open Access Journals (Sweden)

Mozhgan Soltani

2014-10-01

Full Text Available Background: Holothuroids (sea cucumbers are members of the phylum echinodermata, which produce saponins. Saponins exhibit a wide spectrum of pharmacological and biological activities. In this study, we isolated the crude saponins from the body wall of the dominant Iranian species of sea cucumber, Holothuria leucospilota (H. leucospilota. The purpose of this study was to confirm the presence of saponins in the Persian Gulf H. leucospilota and study the hemolytic and cytotoxic activities of these compounds. Methods: The body wall of sea cucumber was dried and powdered and the crude saponins were isolated using various solvents. The crude saponins were further purified by column chromatography using HP-20 resin. The foam test, Thin Layer Chromatography (TLC, hemolytic assay, and Fourier Transform Infrared Spectroscopy (FTIR confirmed the presence of saponins. Cytotoxicity was analyzed using a 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT assay on A549 cells, a human lung cancer cell line. Results: The foam test, hemolytic assay, and TLC supported the presence of saponin compounds in the 80% ethanol fraction of H. leucospilota. The infrared (IR spectrum of the extract showed hydroxyl (-OH, alkyl (C-H, ether (C-O and ester (–C=O absorption characteristic of teriterpenoid saponins. The C-O-C absorption indicated glycoside linkages to the sapogenins. The crude saponin extracted from sea cucumber was cytotoxic to A549 cells. Conclusion: The 80% ethanol fraction of saponin isolated from H. leucospilota exhibited hemolytic activity and offers promise as an anti-cancer candidate.

The Sea Cucumber Body Wall Extract Promoted in Vitro Maturation of NMRI Mice Follicles at Germinal Vesicle Stage

Directory of Open Access Journals (Sweden)

Mitra Khalilzadeh

2016-07-01

Full Text Available Background IVM (in vitro maturation appear to be certified high pregnancy outcome. Therefore, attempt to find an appropriate culture system using natural products for increasing developmental competencies fascinating. Objectives This experiment is aimed to evaluate the effect of sea cucumber methanol extract on in vitro maturation of immature mouse oocyte. Methods In this experimental study, Preantral follicles at germinal vesicle stage were collected from 24 - 26 days NMRI female mouse ovaries and transferred to IVM medium supplemented with different concentration of sea cucumber methanol extract (5, 10, 20, 30 µg/mL. Antioxidant capacity of sea cucumber extract was evaluated using DPPH (2, 2-diphenyl-1-picrylhydrazyl assay. Further, oocyte maturation and TNF-α expression were recorded till day 10th. Data were analyzed by one-way analysis of variance (ANOVA through SPSS 16. Results The percentage of arrested oocyte at germinal vesicle stage in the control group was significantly (P < 0.05 higher than treated group (20 µg/mL. There were significant (P < 0.01 differences in percentage of maturated oocyte to metaphase II (MII stage between treated and control group. DPPH radical scavenging capacity and reduction of TNF-α expression in treated oocyte demonstrated that sea cucumber increased rate of oocyte maturation. In addition, the treated oocyte (20 µg/mL achieved the highest percentage of MII stage. Conclusions It was concluded that the sea cucumber extract with optimum concentration can improve oocyte maturation. Sea cucumber extract treatment can be suggested as a novel therapeutic strategy to be used in infertility modality in the future.

Dry wall Kras 2011

Directory of Open Access Journals (Sweden)

Domen Zupančič

2012-01-01

Full Text Available Despite the modesty of hiska, they show a simple understanding of corbelling technique. One could say they are all examples of human landscape cultivation. Although there is no evident common line when comparing all types of hiska, the cunning eye may observe one shared feature: the positioning of the entrance. More or less all the documented shelters have south or south-western facing entrances. The burja is a cold northerly wind; from the south (Adriatic Sea the winds are warmer. When resting, the setting sun is taken as a sign of the ending of the working day and a reward for the whole day’s efforts. Entrances are the only openings to these structures, and they should serve as well as possible - to watch over the crops, to wait when hunting, to enjoy the calm of evening light, to breathe the sea wind.The syntax of the architectural language of layering stone and shaping the pattern of the landscape remain an inventive realisation of spatial ideas from the past until today. Not only ideas of shaping space - these ideas are basic interventions in the natural habitat which contribute to survival. Culture and an awareness of its values are the origins of local development and reasonable heritage preservation. The next step are tutorial days with workshops on how to build dry stone structures, walls and other stone architecture, as the DSWA organisation in the UK is doing.

Uptake of uranium from sea water by Synechococcus elongatus

International Nuclear Information System (INIS)

Horikoshi, Takao; Nakajima, Akira; Sakaguchi, Takashi

1979-01-01

Basic features of the uranium uptake by Synechococcus elongatus, and the factors affecting it were examined. Synechococcus elongatus was grown in Roux flasks containing 1 liter of culture solution in light (20,000 lux) and with aeration at 30 deg C. Synechococcus cells in the linear growth phase were collected by centrifugation at 6,000 x g for 5 minutes, washed with sea water, and used for the uranium-uptake experiments. The uptake of uranium from sea water containing 1 ppm of the element was strongly affected by the pH of sea water. The optimum uptake was at pH 5. Presence of carbonate ions markedly inhibited and decarbonation of sea water greatly enhanced the uptake. Absorption of uranium by Synechococcus cells was initially rapid, and reached a plateau within 24 hours. The uranium accumulation capacity of Synechococcus cells was increased by heat treatment, the capacity of scalded cells being about twice as much as that of living cells. Most of the uranium absorbed by Synechococcus was found in the inner space of the cells, and only a small amount was present in the cell walls. (Kaihara, S.)

Organic walled dinoflagellate cysts from the Tarim Basin, western China: Implications for the retreat of the Paratethys Sea

NARCIS (Netherlands)

Grothe, A.; Houben, A.J.P.; Bosboom, R.E.; Dupont-Nivet, G.; Brinkhuis, H.

2011-01-01

Paleogene sediments of the Tarim basin in western China hold the easternmost extent of the Paratethys Sea, an epicontinental sea that covered a large part of Eurasia and probably extended to the Mediterranean Tethys in the west. The late Cretaceous and Paleogene sedimentary record of the

A new genus and a new species in the sea cucumber subfamily Colochirinae (Echinodermata: Holothuroidea: Dendrochirotida: Cucumariidae) in the Mediterranean Sea.

Science.gov (United States)

Mjobo, Sifiso; Thandar, Ahmed S

2016-11-09

A new genus Hemiocnus is here erected to accommodate the Mediterranean dendrochirotid sea cucumber Cladodactyla syracusana Grube, currently classified, with some doubt, in the cucumariid genus Pseudocnella. At the same time a new cucumariid species, Hemiocnus rubrobrunneus, is described from some Tunisian material, misidentified as Pseudocnella syracusana (Grube), received from the United States National Museum. The new genus appears most closely related to Pseudocnella than to any other genus within the Colochirinae. Although its body wall ossicles resemble those of Pseudocnella spp. it differs in that the two ventral-most tentacles are reduced and in the presence of rosettes in the tentacles. P. syracusana also cannot be classified in Ocnus because of the presence of multi-layered, fir-cone shaped plates in the body wall, often with one end denticulate; such ossicles are lacking in the type species of the latter genus. The new species, Hemiocnus rubrobrunneus, on the other hand, shows some resemblance to H. syracusanus in its characteristic buttons and incomplete baskets, differing in its softer body wall, lack of fir-cone-shaped plates and in the presence of rosettes and complete baskets in the body wall. There are also some resemblances of the new species to the Mediterranean species of Ocnus viz. O. brunneus, O. planci and O. lacteus, but the soft nature of the body wall, shallow quadrilocular instead of deep trilocular baskets, and the presence of large knobbed plates in the anal region precludes its inclusion in this genus.

Characteristics of wall pressure over wall with permeable coating

Energy Technology Data Exchange (ETDEWEB)

Song, Woo Seog; Shin, Seungyeol; Lee, Seungbae [Inha Univ., Incheon (Korea, Republic of)

2012-11-15

Fluctuating wall pressures were measured using an array of 16 piezoelectric transducers beneath a turbulent boundary layer. The coating used in this experiment was an open cell, urethane type foam with a porosity of approximately 50 ppi. The ultimate objective of the coating is to provide a mechanical filter to reduce the wall pressure fluctuations. The ultimate objective of the coating is to provide a mechanical filter to reduce the wall pressure fluctuations. The boundary layer on the flat plate was measured by using a hot wire probe, and the CPM method was used to determine the skin friction coefficient. The wall pressure autospectra and streamwise wavenumber frequency spectra were compared to assess the attenuation of the wall pressure field by the coating. The coating is shown to attenuate the convective wall pressure energy. However, the relatively rough surface of the coating in this investigation resulted in a higher mean wall shear stress, thicker boundary layer, and higher low frequency wall pressure spectral levels compared to a smooth wall.

Reinforcement mechanism of multi-anchor wall with double wall facing

Science.gov (United States)

Suzuki, Kouta; Kobayashi, Makoto; Miura, Kinya; Konami, Takeharu; Hayashi, Taketo

2017-10-01

The reinforced soil wall has high seismic performance as generally known. However, the seismic behavior has not been clarified accurately yet, especially on multi-anchor wall with double wall facing. Indefinite behavior of reinforced soil wall during earthquake make us complicated in case with adopting to the abutment, because of arrangement of anchor plate as reinforcement often different according to the width of roads. In this study, a series of centrifuge model tests were carried out to investigate the reinforcement mechanism of multi anchor wall with double wall facing from the perspective of the vertical earth pressure. Several types of reinforce arrangement and rigid wall were applied in order to verify the arch function in the reinforced regions. The test results show unique behavior of vertical earth pressure, which was affected by arch action. All the vertical earth pressure placed behind facing panel, are larger than that of middle part between facing panel despite of friction between backfill and facing panel. Similar results were obtained in case using rigid wall. On the other hands, the vertical earth pressure, which were measured at the 3cm high from bottom of model container, shows larger than that of bottom. This results show the existence of arch action between double walls. In addition, it implies that the wall facing of such soil structure confined the backfill as pseudo wall, which is very reason that the multi anchor wall with double wall facing has high seismic performance.

Wind tunnels with adapted walls for reducing wall interference

Science.gov (United States)

Ganzer, U.

1979-01-01

The basic principle of adaptable wind tunnel walls is explained. First results of an investigation carried out at the Aero-Space Institute of Berlin Technical University are presented for two dimensional flexible walls and a NACA 0012 airfoil. With five examples exhibiting very different flow conditions it is demonstrated that it is possible to reduce wall interference and to avoid blockage at transonic speeds by wall adaptation.

Wave simulation for the design of an innovative quay wall: the case of Vlorë Harbour

Science.gov (United States)

Antonini, Alessandro; Archetti, Renata; Lamberti, Alberto

2017-01-01

Sea states and environmental conditions are basic data for the design of marine structures. Hindcasted wave data have been applied here with the aim of identifying the proper design conditions for an innovative quay wall concept. In this paper, the results of a computational fluid dynamics model are used to optimise the new absorbing quay wall of Vlorë Harbour (Republic of Albania) and define the design loads under extreme wave conditions. The design wave states at the harbour entrance have been estimated analysing 31 years of hindcasted wave data simulated through the application of WaveWatch III. Due to the particular geography and topography of the Bay of Vlorë, wave conditions generated from the north-west are transferred to the harbour entrance with the application of a 2-D spectral wave module, whereas southern wave states, which are also the most critical for the port structures, are defined by means of a wave generation model, according to the available wind measurements. Finally, the identified extreme events have been used, through the NewWave approach, as boundary conditions for the numerical analysis of the interaction between the quay wall and the extreme events. The results show that the proposed method, based on numerical modelling at different scales from macro to meso and to micro, allows for the identification of the best site-specific solutions, also for a location devoid of any wave measurement. In this light, the objectives of the paper are two-fold. First, they show the application of sea condition estimations through the use of wave hindcasted data in order to properly define the design wave conditions for a new harbour structure. Second, they present a new approach for investigating an innovative absorbing quay wall based on CFD modelling and the NewWave theory.

Inverse measurement of wall pressure field in flexible-wall wind tunnels using global wall deformation data

Science.gov (United States)

Brown, Kenneth; Brown, Julian; Patil, Mayuresh; Devenport, William

2018-02-01

The Kevlar-wall anechoic wind tunnel offers great value to the aeroacoustics research community, affording the capability to make simultaneous aeroacoustic and aerodynamic measurements. While the aeroacoustic potential of the Kevlar-wall test section is already being leveraged, the aerodynamic capability of these test sections is still to be fully realized. The flexibility of the Kevlar walls suggests the possibility that the internal test section flow may be characterized by precisely measuring small deflections of the flexible walls. Treating the Kevlar fabric walls as tensioned membranes with known pre-tension and material properties, an inverse stress problem arises where the pressure distribution over the wall is sought as a function of the measured wall deflection. Experimental wall deformations produced by the wind loading of an airfoil model are measured using digital image correlation and subsequently projected onto polynomial basis functions which have been formulated to mitigate the impact of measurement noise based on a finite-element study. Inserting analytic derivatives of the basis functions into the equilibrium relations for a membrane, full-field pressure distributions across the Kevlar walls are computed. These inversely calculated pressures, after being validated against an independent measurement technique, can then be integrated along the length of the test section to give the sectional lift of the airfoil. Notably, these first-time results are achieved with a non-contact technique and in an anechoic environment.

Sea level trends in Southeast Asian seas

Science.gov (United States)

Strassburg, M. W.; Hamlington, B. D.; Leben, R. R.; Manurung, P.; Lumban Gaol, J.; Nababan, B.; Vignudelli, S.; Kim, K.-Y.

2015-05-01

Southeast Asian seas span the largest archipelago in the global ocean and provide a complex oceanic pathway connecting the Pacific and Indian oceans. The Southeast Asian sea regional sea level trends are some of the highest observed in the modern satellite altimeter record that now spans almost 2 decades. Initial comparisons of global sea level reconstructions find that 17-year sea level trends over the past 60 years exhibit good agreement with decadal variability associated with the Pacific Decadal Oscillation and related fluctuations of trade winds in the region. The Southeast Asian sea region exhibits sea level trends that vary dramatically over the studied time period. This historical variation suggests that the strong regional sea level trends observed during the modern satellite altimeter record will abate as trade winds fluctuate on decadal and longer timescales. Furthermore, after removing the contribution of the Pacific Decadal Oscillation (PDO) to sea level trends in the past 20 years, the rate of sea level rise is greatly reduced in the Southeast Asian sea region. As a result of the influence of the PDO, the Southeast Asian sea regional sea level trends during the 2010s and 2020s are likely to be less than the global mean sea level (GMSL) trend if the observed oscillations in wind forcing and sea level persist. Nevertheless, long-term sea level trends in the Southeast Asian seas will continue to be affected by GMSL rise occurring now and in the future.

Assessment of dry-stone terrace wall degradation with a 3D approach

Science.gov (United States)

Djuma, Hakan; Camera, Corrado; Faka, Marina; Bruggeman, Adriana; Hermon, Sorin

2016-04-01

In the Mediterranean basin, terracing is a common element of agricultural lands. Terraces retained by dry-stone walls are used to conserve arable soil, delay erosion processes and retain rainfall runoff. Currently, agricultural land abandonment is widespread in the Mediterranean region leading to terrace wall failure due to lack of maintenance and consequently an increase in soil erosion. The objective of this study is to test the applicability of digital 3D documentation on mountainous agricultural areas for assessing changes in terrace wall geometry, including terrace wall failures and associated soil erosion. The study area is located at 800-1100 m above sea level, in the Ophiolite complex of the Troodos Mountains in Cyprus. Average annual precipitation is 750 mm. Two sites with dry-stone terraces were selected for this study. The first site had a sequence of three terrace walls that were surveyed. The uppermost terrace wall was collapsed at several locations; the middle at few locations; and the lowest was still intact. Three fieldwork campaigns were conducted at this site: during the dry season (initial conditions), the middle and end of the wet season. The second site had one terrace wall that was almost completely collapsed. This terrace was restored during a communal terrace rehabilitation event. Two fieldwork campaigns were conducted for this terrace: before and after the terrace wall restoration. Terrace walls were documented with a set of digital images, and transformed into a 3D point cloud (using web-based services and commercial software - Autodesk 123D catch and Menci Software uMap, respectively). A set of points, registered with the total station and geo-referenced with a GPS, enabled the scaling of the 3D model and aligning the terrace walls within the same reference system. The density (distance between each point) of the reconstructed point clouds is 0.005 m by Umap and 0.025 m by 123D Catch. On the first site, the model analysis identified wall

Wall-based identification of coherent structures in wall-bounded turbulence

Science.gov (United States)

Sanmiguel Vila, C.; Flores, O.

2018-04-01

During the last decades, a number of reduced order models based on coherent structures have been proposed to describe wall-bounded turbulence. Many of these models emphasize the importance of coherent wall-normal velocity eddies (ν-eddies), which drive the generation of the very long streamwise velocity structures observed in the logarithmic and outer region. In order to use these models to improve our ability to control wall-bounded turbulence in realistic applications, these ν-eddies need to be identified from the wall in a non-intrusive way. In this paper, the possibility of using the pressure signal at the wall to identify these ν-eddies is explored, analyzing the cross-correlation between the wall-normal velocity component and the pressure fluctuations at the wall in a DNS of a turbulent channel flow at Reτ = 939. The results show that the cross-correlation has a region of negative correlation upstream, and a region of positive correlation backwards. In the spanwise direction the correlation decays monotonously, except very close to the wall where a change of sign of the correlation coefficient is observed. Moreover, filtering the pressure fluctuations at the wall in space results in an increase of the region where the cross-correlation is strong, both for the positively and the negatively correlated regions. The use of a time filter for the pressure fluctuations at the wall yields different results, displacing the regions of strong correlation without changing much their sizes. The results suggest that space-filtering the pressure at the wall is a feasible way to identify ν-eddies of different sizes, which could be used to trigger turbulent control strategies.

IBT-based quantitative proteomics identifies potential regulatory proteins involved in pigmentation of purple sea cucumber, Apostichopus japonicus.

Science.gov (United States)

Xing, Lili; Sun, Lina; Liu, Shilin; Li, Xiaoni; Zhang, Libin; Yang, Hongsheng

2017-09-01

Sea cucumbers are an important economic species and exhibit high yield value among aquaculture animals. Purple sea cucumbers are very rare and beautiful and have stable hereditary patterns. In this study, isobaric tags (IBT) were first used to reveal the molecular mechanism of pigmentation in the body wall of the purple sea cucumber. We analyzed the proteomes of purple sea cucumber in early pigmentation stage (Pa), mid pigmentation stage (Pb) and late pigmentation stage (Pc), resulting in the identification of 5580 proteins, including 1099 differentially expressed proteins in Pb: Pa and 339 differentially expressed proteins in Pc: Pb. GO and KEGG analyses revealed possible differentially expressed proteins, including"melanogenesis", "melanosome", "melanoma", "pigment-biosynthetic process", "Epidermis development", "Ras-signaling pathway", "Wnt-signaling pathway", "response to UV light", and "tyrosine metabolism", involved in pigment synthesis and regulation in purple sea cucumbers. The large number of differentially expressed proteins identified here should be highly useful in further elucidating the mechanisms underlying pigmentation in sea cucumbers. Furthermore, these results may also provide the base for further identification of proteins involved in resistance mechanisms against melanoma, albinism, UV damage, and other diseases in sea cucumbers. Copyright © 2017. Published by Elsevier Inc.

T-antigen binding lectin with antibacterial activity from marine invertebrate, sea cucumber (Holothuria scabra): Possible involvement in differential recognition of bacteria

Digital Repository Service at National Institute of Oceanography (India)

Gowda, N.M.; Goswami, U.; Khan, M.I.

report a study of a lectin (HSL) involved in immune response in the echinoderm, sea cucumber (Holothuria scabra). Correlative studies indicate that the expression of this defensive lectin is induced by bacterial challenge, wherein cell wall...

Novel Use of PIT Tags in Sea Cucumbers: Promising Results with the Commercial Species Cucumaria frondosa.

Directory of Open Access Journals (Sweden)

Bruno L Gianasi

Full Text Available The lack of a reliable and innocuous mark-recapture method has limited studies that would provide essential information for the management of commercial sea cucumbers. Tagging sea cucumbers is notoriously difficult because of their plastic nature and autolysis capacities. The markers that have so far been tested, mainly on or through the body wall, were either lost rapidly or had major drawbacks (e.g. suitable only for batch identification, requiring complex analysis, causing infections, necrosis, behavioural changes and mortality. The present study explored the efficacy of passive integrated transponder (PIT tags for individually marking sea cucumbers by assessing retention rates and long-term side effects of tags inserted in previously unstudied tissues/organs. Individuals of the species Cucumaria frondosa were tagged in the body wall, aquapharyngeal bulb and at the base of the oral tentacles. They were monitored closely for evidence of stress, infection, change in feeding and spawning behaviour and tag retention rate. Implanting the tag in an oral tentacle to reach the hydrovascular system of the aquapharyngeal bulb achieved the best retention rates in full-size individuals: from a maximum of 92% after 30 days to 68% at the end of the experimental period (300 days. Efficacy was lower in smaller individuals (84% after 30 d and 42% after 300 d. Following a slight increase in cloacal movements for 15 h post tagging, no side effect was noted in sea cucumbers tagged in the aquapharyngeal bulb via the tentacles. Feeding and spawning behaviours were not affected and no signs of infections or abnormal cell development in the vicinity of the tags were observed. This study indicates that marking sea cucumbers with 8.2 mm long PIT tags implanted via the oral tentacle is an effective technique, yielding relatively high retention rates over long periods without any detectable physiological or behavioural effects.

Wall Shear Stress, Wall Pressure and Near Wall Velocity Field Relationships in a Whirling Annular Seal

Science.gov (United States)

Morrison, Gerald L.; Winslow, Robert B.; Thames, H. Davis, III

1996-01-01

The mean and phase averaged pressure and wall shear stress distributions were measured on the stator wall of a 50% eccentric annular seal which was whirling in a circular orbit at the same speed as the shaft rotation. The shear stresses were measured using flush mounted hot-film probes. Four different operating conditions were considered consisting of Reynolds numbers of 12,000 and 24,000 and Taylor numbers of 3,300 and 6,600. At each of the operating conditions the axial distribution (from Z/L = -0.2 to 1.2) of the mean pressure, shear stress magnitude, and shear stress direction on the stator wall were measured. Also measured were the phase averaged pressure and shear stress. These data were combined to calculate the force distributions along the seal length. Integration of the force distributions result in the net forces and moments generated by the pressure and shear stresses. The flow field inside the seal operating at a Reynolds number of 24,000 and a Taylor number of 6,600 has been measured using a 3-D laser Doppler anemometer system. Phase averaged wall pressure and wall shear stress are presented along with phase averaged mean velocity and turbulence kinetic energy distributions located 0.16c from the stator wall where c is the seal clearance. The relationships between the velocity, turbulence, wall pressure and wall shear stress are very complex and do not follow simple bulk flow predictions.

Ambiguous walls

DEFF Research Database (Denmark)

Mody, Astrid

2012-01-01

The introduction of Light Emitting Diodes (LEDs) in the built environment has encouraged myriad applications, often embedded in surfaces as an integrated part of the architecture. Thus the wall as responsive luminous skin is becoming, if not common, at least familiar. Taking into account how walls...... have encouraged architectural thinking of enclosure, materiality, construction and inhabitation in architectural history, the paper’s aim is to define new directions for the integration of LEDs in walls, challenging the thinking of inhabitation and program. This paper introduces the notion...... of “ambiguous walls” as a more “critical” approach to design [1]. The concept of ambiguous walls refers to the diffuse status a lumious and possibly responsive wall will have. Instead of confining it can open up. Instead of having a static appearance, it becomes a context over time. Instead of being hard...

High-R Walls for Remodeling: Wall Cavity Moisture Monitoring

Energy Technology Data Exchange (ETDEWEB)

Wiehagen, J.; Kochkin, V.

2012-12-01

The focus of the study is on the performance of wall systems, and in particular, the moisture characteristics inside the wall cavity and in the wood sheathing. Furthermore, while this research will initially address new home construction, the goal is to address potential moisture issues in wall cavities of existing homes when insulation and air sealing improvements are made.

High-R Walls for Remodeling. Wall Cavity Moisture Monitoring

Energy Technology Data Exchange (ETDEWEB)

Wiehagen, J. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Kochkin, V. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States)

2012-12-01

The focus of the study is on the performance of wall systems, and in particular, the moisture characteristics inside the wall cavity and in the wood sheathing. Furthermore, while this research will initially address new home construction, the goal is to address potential moisture issues in wall cavities of existing homes when insulation and air sealing improvements are made.

Liquid Wall Chambers

Energy Technology Data Exchange (ETDEWEB)

Meier, W R

2011-02-24

The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

Rising damp in building walls: the wall base ventilation system

Energy Technology Data Exchange (ETDEWEB)

Guimaraes, A.S.; Delgado, J.M.P.Q.; Freitas, V.P. de [Faculdade de Engenharia da Universidade do Porto, Laboratorio de Fisica das Construcoes (LFC), Departamento de Engenharia Civil, Porto (Portugal)

2012-12-15

This work intends to validate a new system for treating rising damp in historic buildings walls. The results of laboratory experiments show that an efficient way of treating rising damp is by ventilating the wall base, using the HUMIVENT technique. The analytical model presented describes very well the observed features of rising damp in walls, verified by laboratory tests, who contributed for a simple sizing of the wall base ventilation system that will be implemented in historic buildings. (orig.)

Eddy Covariance Measurements of the Sea-Spray Aerosol Flu

Science.gov (United States)

Brooks, I. M.; Norris, S. J.; Yelland, M. J.; Pascal, R. W.; Prytherch, J.

2015-12-01

Historically, almost all estimates of the sea-spray aerosol source flux have been inferred through various indirect methods. Direct estimates via eddy covariance have been attempted by only a handful of studies, most of which measured only the total number flux, or achieved rather coarse size segregation. Applying eddy covariance to the measurement of sea-spray fluxes is challenging: most instrumentation must be located in a laboratory space requiring long sample lines to an inlet collocated with a sonic anemometer; however, larger particles are easily lost to the walls of the sample line. Marine particle concentrations are generally low, requiring a high sample volume to achieve adequate statistics. The highly hygroscopic nature of sea salt means particles change size rapidly with fluctuations in relative humidity; this introduces an apparent bias in flux measurements if particles are sized at ambient humidity. The Compact Lightweight Aerosol Spectrometer Probe (CLASP) was developed specifically to make high rate measurements of aerosol size distributions for use in eddy covariance measurements, and the instrument and data processing and analysis techniques have been refined over the course of several projects. Here we will review some of the issues and limitations related to making eddy covariance measurements of the sea spray source flux over the open ocean, summarise some key results from the last decade, and present new results from a 3-year long ship-based measurement campaign as part of the WAGES project. Finally we will consider requirements for future progress.

Sea surface temperatures and salinities from platforms in the Barents Sea, Sea of Japan, North Atlantic Ocean, Philippine Sea, Red Sea, and the South China Sea (Nan Hai) from 1896-1950 (NODC Accession 0000506)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Surface temperatures and salinities were collected in the Barents Sea, Sea of Japan, North Atlantic Ocean, Philippine Sea, Red Sea, and South China Sea (Nan Hai)...

Chemical Profiling and Bioactivity of Body Wall Lipids from Strongylocentrotus droebachiensis

Directory of Open Access Journals (Sweden)

Alexander N. Shikov

2017-11-01

Full Text Available The lipids from gonads and polyhydroxynaphthoquinone pigments from body walls of sea urchins are intensively studied. However, little is known about the body wall (BW lipids. Ethanol extract (55 °C contained about equal amounts of saturated (SaFA and monounsaturated fatty acids (MUFA representing 60% of total fatty acids, with myristic, palmitic and eicosenoic acids as major SaFAs and MUFAs, respectively. Non-methylene-interrupted dienes (13% were composed of eicosadienoic and docosadienoic acids. Long-chain polyunsaturated fatty acids (LC-PUFA included two main components, n6 arachidonic and n3 eicosapentaenoic acids, even with equal concentrations (15 μg/mg and a balanced n6/n3 PUFA ratio (0.86. The UPLC-ELSD analysis showed that a great majority of the lipids (80% in the ethanolic extract were phosphatidylcholine (60 μg/mg and phosphatidylethanolamine (40 μg/mg, while the proportion of neutral lipids remained lower than 20%. In addition, alkoxyglycerol derivatives—chimyl, selachyl, and batyl alcohols—were quantified. We have assumed that the mechanism of action of body wall lipids in the present study is via the inhibition of MAPK p38, COX-1, and COX-2. Our findings open the prospective to utilize this lipid fraction as a source for the development of drugs with anti-inflammatory activity.

Observational analysis of air-sea fluxes and sea water temperature offshore South China Sea

Science.gov (United States)

Bi, X.; Huang, J.; Gao, Z.; Liu, Y.

2017-12-01

This paper investigates the air-sea fluxes (momentum flux, sensible heat flux and latent heat flux) from eddy covariance method based on data collected at an offshore observation tower in the South China Sea from January 2009 to December 2016 and sea water temperature (SWT) on six different levels based on data collected from November 2011 to June 2013. The depth of water at the tower over the sea averages about 15 m. This study presents the in-situ measurements of continuous air-sea fluxes and SWT at different depths. Seasonal and diurnal variations in air-sea fluxes and SWT on different depths are examined. Results show that air-sea fluxes and all SWT changed seasonally; sea-land breeze circulation appears all the year round. Unlike winters where SWT on different depths are fairly consistent, the difference between sea surface temperature (SST) and sea temperature at 10 m water depth fluctuates dramatically and the maximum value reaches 7 °C during summer.

Effects of endogenous cysteine proteinases on structures of collagen fibres from dermis of sea cucumber (Stichopus japonicus).

Science.gov (United States)

Liu, Yu-Xin; Zhou, Da-Yong; Ma, Dong-Dong; Liu, Zi-Qiang; Liu, Yan-Fei; Song, Liang; Dong, Xiu-Ping; Li, Dong-Mei; Zhu, Bei-Wei; Konno, Kunihiko; Shahidi, Fereidoon

2017-10-01

Autolysis of sea cucumber, caused by endogenous enzymes, leads to postharvest quality deterioration of sea cucumber. However, the effects of endogenous proteinases on structures of collagen fibres, the major biologically relevant substrates in the body wall of sea cucumber, are less clear. Collagen fibres were prepared from the dermis of sea cucumber (Stichopus japonicus), and the structural consequences of degradation of the collagen fibres caused by endogenous cysteine proteinases (ECP) from Stichopus japonicus were examined. Scanning electron microscopic images showed that ECP caused partial disaggregation of collagen fibres into collagen fibrils by disrupting interfibrillar proteoglycan bridges. Differential scanning calorimetry and Fourier transform infrared analysis revealed increased structural disorder of fibrillar collagen caused by ECP. SDS-PAGE and chemical analysis indicated that ECP can liberate glycosaminoglycan, hydroxyproline and collagen fragments from collagen fibres. Thus ECP can cause disintegration of collagen fibres by degrading interfibrillar proteoglycan bridges. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bioaccumulation of PCBs in the sea urchin Paracentrotus lividus: seawater and food exposures to a 14C-radiolabelled congener (PCB no. 153)

International Nuclear Information System (INIS)

Danis, B.; Cotret, O.; Teyssie, J.L.; Bustamante, P.; Fowler, S.W.; Warnau, M.

2005-01-01

Adult Paracentrotus lividus were exposed to a 14 C-labelled PCB congener (PCB no. 153) using two different exposure modes: (1) the surrounding sea water and (2) the food (viz. the phanerogam Posidonia oceanica and the brown alga Taonia atomaria). Uptake kinetics from water and loss kinetics after single feeding were followed in four body compartments of the sea urchins (body wall, spines, gut and gonads). Results indicate that PCB bioaccumulation in P. lividus varies from one body compartment to another, with the exposure mode and the nature of the food. The echinoids accumulate PCB no. 153 more efficiently when exposed via water than via the food (the transfer efficiency is higher by one order of magnitude). Target body compartments of PCB no. 153 were found to be body wall and spines when individuals were exposed via water, and gut when they were exposed via food. It is concluded that P. lividus is an efficient bioaccumulator of PCB and that it could be considered as an interesting indicator for monitoring PCB contamination in the marine environment. - The sea urchin Paracentrotus lividus is a valuable indicator for PCB contamination

Growth, metabolism and physiological response of the sea cucumber, Apostichopus japonicus Selenka during periods of inactivity

Science.gov (United States)

Du, Rongbin; Zang, Yuanqi; Tian, Xiangli; Dong, Shuanglin

2013-03-01

The growth, metabolism and physiological response of the sea cucumber, Apostichopus japonicus, were investigated during periods of inactivity. The body weight, oxygen consumption rate (OCR), activities of acidic phosphatase (ACP), alkaline phosphatase (AKP), catalase (CAT) and superoxide dismutase (SOD), and content of heat shock protein 70 (Hsp70) in the body wall and coelomic fluid of A. japonicus were measured during starvation, experimental aestivation and aestivation. The results showed that the body weight of sea cucumber in the three treatments decreased significantly during the experimental period ( P sea cucumber reduced in starvation and experimental aestivation treatments, but increased gradually in natural aestivation treatment. The activities of ACP and AKP of sea cucumber decreased gradually in all treatments, whereas those of SOD and CAT as well as Hsp70 content decreased in the starvation and experimental aestivation treatments and increased in natural aestivation treatment. The sea cucumber entered a state of aestivation at 24°C. To some extent, the animals in experimental aestivation were different from those in natural aestivation in metabolism and physiological response. These findings suggested that the aestivation mechanism of A. japonicus is complex and may not be attributed to the elevated temperature only.

The distribution and diversity of sea cucumbers in the coral reefs of the South China Sea, Sulu Sea and Sulawesi Sea

Science.gov (United States)

Woo, Sau Pinn; Yasin, Zulfigar; Ismail, Siti Hasmah; Tan, Shau Hwai

2013-11-01

A study on the distribution and diversity of sea cucumbers in the coral reefs of the South China Sea, Sulu Sea and Sulawesi Sea was carried out in July 2009. The survey was done using wandering transect underwater with SCUBA. Twelve species of sea cucumber were found from four different families and nine genera. The most dominant family was Holothuriidae (five species), followed by Stichopodidae (three species), Synaptidae (three species) and Cucumariidae with only one species. The most dominant species found around the island was Pearsonothuria graffei, which can be found abundantly on substrate of dead corals in a wide range of depth (6-15 m). The Sulawesi Sea showed a higher diversity of sea cucumber with seven different species compared to the South China Sea with only six different species and Sulu Sea with only two species. Ordination by multidimensional scaling of Bray-Curtis similarities clustered the sampling locations to three main clusters with two outgroups. Previous studies done indicated a higher diversity of sea cucumber as compared to this study. This can be indication that the population and diversity of sea cucumbers in the reef is under threat.

Cell Wall Remodeling Enzymes Modulate Fungal Cell Wall Elasticity and Osmotic Stress Resistance.

Science.gov (United States)

Ene, Iuliana V; Walker, Louise A; Schiavone, Marion; Lee, Keunsook K; Martin-Yken, Hélène; Dague, Etienne; Gow, Neil A R; Munro, Carol A; Brown, Alistair J P

2015-07-28

The fungal cell wall confers cell morphology and protection against environmental insults. For fungal pathogens, the cell wall is a key immunological modulator and an ideal therapeutic target. Yeast cell walls possess an inner matrix of interlinked β-glucan and chitin that is thought to provide tensile strength and rigidity. Yeast cells remodel their walls over time in response to environmental change, a process controlled by evolutionarily conserved stress (Hog1) and cell integrity (Mkc1, Cek1) signaling pathways. These mitogen-activated protein kinase (MAPK) pathways modulate cell wall gene expression, leading to the construction of a new, modified cell wall. We show that the cell wall is not rigid but elastic, displaying rapid structural realignments that impact survival following osmotic shock. Lactate-grown Candida albicans cells are more resistant to hyperosmotic shock than glucose-grown cells. We show that this elevated resistance is not dependent on Hog1 or Mkc1 signaling and that most cell death occurs within 10 min of osmotic shock. Sudden decreases in cell volume drive rapid increases in cell wall thickness. The elevated stress resistance of lactate-grown cells correlates with reduced cell wall elasticity, reflected in slower changes in cell volume following hyperosmotic shock. The cell wall elasticity of lactate-grown cells is increased by a triple mutation that inactivates the Crh family of cell wall cross-linking enzymes, leading to increased sensitivity to hyperosmotic shock. Overexpressing Crh family members in glucose-grown cells reduces cell wall elasticity, providing partial protection against hyperosmotic shock. These changes correlate with structural realignment of the cell wall and with the ability of cells to withstand osmotic shock. The C. albicans cell wall is the first line of defense against external insults, the site of immune recognition by the host, and an attractive target for antifungal therapy. Its tensile strength is conferred by

Solar Walls in tsbi3

DEFF Research Database (Denmark)

Wittchen, Kim Bjarne

tsbi3 is a user-friendly and flexible computer program, which provides support to the design team in the analysis of the indoor climate and the energy performance of buildings. The solar wall module gives tsbi3 the capability of simulating solar walls and their interaction with the building....... This version, C, of tsbi3 is capable of simulating five types of solar walls say: mass-walls, Trombe-walls, double Trombe-walls, internally ventilated walls and solar walls for preheating ventilation air. The user's guide gives a description of the capabilities and how to simulate solar walls in tsbi3....

Finite element limit loads for non-idealized through-wall cracks in thick-walled pipe

International Nuclear Information System (INIS)

Shim, Do-Jun; Han, Tae-Song; Huh, Nam-Su

2013-01-01

Highlights: • The lower bound bulging factor of thin-walled pipe can be used for thick-walled pipe. • The limit loads are proposed for thick-walled, transition through-wall cracked pipe. • The correction factors are proposed for estimating limit loads of transition cracks. • The limit loads of short transition cracks are similar to those of idealized cracks. - Abstract: The present paper provides plastic limit loads for non-idealized through-wall cracks in thick-walled pipe. These solutions are based on detailed 3-dimensional finite element (FE) analyses which can be used for structural integrity assessment of nuclear piping. To cover a practical range of interest, the geometric variables and loading conditions affecting the plastic limit loads of thick-walled pipe with non-idealized through-wall cracks were systematically varied. In terms of crack orientation, both circumferential and axial through-wall cracks were considered. As for loading conditions, axial tension, global bending, and internal pressure were considered for circumferential cracks, whereas only internal pressure was considered for axial cracks. Furthermore, the values of geometric factor representing shape characteristics of non-idealized through-wall cracks were also systematically varied. In order to provide confidence in the present FE analyses results, plastic limit loads of un-cracked, thick-walled pipe resulting from the present FE analyses were compared with the theoretical solutions. Finally, correction factors to the idealized through-wall crack solutions were developed to determine the plastic limit loads of non-idealized through-wall cracks in thick-walled pipe

Vibro-acoustic modelling of aircraft double-walls with structural links using Statistical Energy Analysis

Science.gov (United States)

Campolina, Bruno L.

The prediction of aircraft interior noise involves the vibroacoustic modelling of the fuselage with noise control treatments. This structure is composed of a stiffened metallic or composite panel, lined with a thermal and acoustic insulation layer (glass wool), and structurally connected via vibration isolators to a commercial lining panel (trim). The goal of this work aims at tailoring the noise control treatments taking design constraints such as weight and space optimization into account. For this purpose, a representative aircraft double-wall is modelled using the Statistical Energy Analysis (SEA) method. Laboratory excitations such as diffuse acoustic field and point force are addressed and trends are derived for applications under in-flight conditions, considering turbulent boundary layer excitation. The effect of the porous layer compression is firstly addressed. In aeronautical applications, compression can result from the installation of equipment and cables. It is studied analytically and experimentally, using a single panel and a fibrous uniformly compressed over 100% of its surface. When compression increases, a degradation of the transmission loss up to 5 dB for a 50% compression of the porous thickness is observed mainly in the mid-frequency range (around 800 Hz). However, for realistic cases, the effect should be reduced since the compression rate is lower and compression occurs locally. Then the transmission through structural connections between panels is addressed using a four-pole approach that links the force-velocity pair at each side of the connection. The modelling integrates experimental dynamic stiffness of isolators, derived using an adapted test rig. The structural transmission is then experimentally validated and included in the double-wall SEA model as an equivalent coupling loss factor (CLF) between panels. The tested structures being flat, only axial transmission is addressed. Finally, the dominant sound transmission paths are

Novel Enzymes for Targeted Hydrolysis of Algal Cell Walls

DEFF Research Database (Denmark)

Schultz-Johansen, Mikkel

Seaweeds, also known as macroalgae, constitute a rich source of valuable biomolecules which have a potential industrial application in food and pharma products. The use of enzymes can optimize the extraction and separation of these molecules from the seaweed biomass, but most commercial enzymes...... are incapable of breaking the complex polysaccharides found in seaweed cell walls. Therefore, new enzymes are needed for degradation of seaweed biomass. Bacteria that colonize the surfaces of seaweed secrete enzymes that allow them to degrade and utilize seaweed polysaccharides as energy. In addition, sea...... degradation. In addition, three carrageenases were characterised; one as a GH16 κ-carrageenase whereas the other two belong to a new GH16 subfamily of enzymes that degrade furcellaran (κ/β-carrageenan). From metagenome sequence data three putative GH107 fucanases were identified and characterized...

Study on the possibility of sea-disposal of krypton-85

International Nuclear Information System (INIS)

Dalen, A. van; Vons, L.H.; Verkerk, B.

1980-01-01

Results of a feasibility study, performed under a contract with the Commission of the European Communities, regarding technical and radiological aspects of sea-disposal of all krypton-85 retained in a large fuel reprocessing facility, are presented. The design of a double-walled, essentially spherical container is described that provides both double containment of the compressed gas and permanent 'disposable' radiation shielding. Three sizes have been studied, i.e. with internal volumes of 0.01, 0.05 and 0.1 m 3 , each designed to hold 0.1 m 3 (STP) of krypton, and each containing approximately 400 TBq of 85 Kr per 0.001 m 3 sphere volume. This results in an internal heat production of 17.5 kW/m 3 . Calculations of temperatures and stresses that would result from the conditions of the required fire test for B(U) transport packages showed that the design would allow the containers to pass this test. Radiological consequences have been considered for disposal of petabecquerel amounts of 85 Kr as a function of undamaged container lifetime on the sea bed. Finally, an indication is given of the necessary amendments to the London Convention in order to allow sea-disposal of these large amounts of radioactive krypton. (author)

Ambiguous walls

DEFF Research Database (Denmark)

Mody, Astrid

2012-01-01

The introduction of Light Emitting Diodes (LEDs) in the built environment has encouraged myriad applications, often embedded in surfaces as an integrated part of the architecture. Thus the wall as responsive luminous skin is becoming, if not common, at least familiar. Taking into account how wall...

Wind-sea surface temperature-sea ice relationship in the Chukchi-Beaufort Seas during autumn

Science.gov (United States)

Zhang, Jing; Stegall, Steve T.; Zhang, Xiangdong

2018-03-01

Dramatic climate changes, especially the largest sea ice retreat during September and October, in the Chukchi-Beaufort Seas could be a consequence of, and further enhance, complex air-ice-sea interactions. To detect these interaction signals, statistical relationships between surface wind speed, sea surface temperature (SST), and sea ice concentration (SIC) were analyzed. The results show a negative correlation between wind speed and SIC. The relationships between wind speed and SST are complicated by the presence of sea ice, with a negative correlation over open water but a positive correlation in sea ice dominated areas. The examination of spatial structures indicates that wind speed tends to increase when approaching the ice edge from open water and the area fully covered by sea ice. The anomalous downward radiation and thermal advection, as well as their regional distribution, play important roles in shaping these relationships, though wind-driven sub-grid scale boundary layer processes may also have contributions. Considering the feedback loop involved in the wind-SST-SIC relationships, climate model experiments would be required to further untangle the underlying complex physical processes.

Operational Windows for Dry-Wall and Wetted-Wall IFE Chambers

International Nuclear Information System (INIS)

Najmabadi, F.; Raffray, A.R.; Bromberg, L.

2004-01-01

The ARIES-IFE study was an integrated study of inertial fusion energy (IFE) chambers and chamber interfaces with the driver and target systems. Detailed analysis of various subsystems was performed parametrically to uncover key physics/technology uncertainties and to identify constraints imposed by each subsystem. In this paper, these constraints (e.g., target injection and tracking, thermal response of the first wall, and driver propagation and focusing) were combined to understand the trade-offs, to develop operational windows for chamber concepts, and to identify high-leverage research and development directions for IFE research. Some conclusions drawn in this paper are (a) the detailed characterization of the target yield and spectrum has a major impact on the chamber; (b) it is prudent to use a thin armor instead of a monolithic first wall for dry-wall concepts; (c) for dry-wall concepts with direct-drive targets, the most stringent constraint is imposed by target survival during the injection process; (d) for relatively low yield targets (<250 MJ), an operational window with no buffer gas may exist; (e) for dry-wall concepts with indirect-drive targets, a high buffer gas pressure would be necessary that may preclude propagation of the laser driver and require assisted pinch transport for the heavy-ion driver; and (f) generation and transport of aerosols in the chamber is the key feasibility issue for wetted-wall concepts

Hard wall - soft wall - vorticity scattering in shear flow

NARCIS (Netherlands)

Rienstra, S.W.; Singh, D.K.

2014-01-01

An analytically exact solution, for the problem of lowMach number incident vorticity scattering at a hard-soft wall transition, is obtained in the form of Fourier integrals by using theWiener-Hopf method. Harmonic vortical perturbations of inviscid linear shear flow are scattered at the wall

Hard wall - soft wall - vorticity scattering in shear flow

NARCIS (Netherlands)

Rienstra, S.W.; Singh, D.K.

2014-01-01

An analytically exact solution, for the problem of low Mach number incident vorticity scattering at a hard-soft wall transition, is obtained in the form of Fourier integrals by using the Wiener-Hopf method. Harmonic vortical perturbations of inviscid linear shear flow are scattered at the wall

Regulation of cell wall biosynthesis.

Science.gov (United States)

Zhong, Ruiqin; Ye, Zheng-Hua

2007-12-01

Plant cell walls differ in their amount and composition among various cell types and even in different microdomains of the wall of a given cell. Plants must have evolved regulatory mechanisms controlling biosynthesis, targeted secretion, and assembly of wall components to achieve the heterogeneity in cell walls. A number of factors, including hormones, the cytoskeleton, glycosylphosphatidylinositol-anchored proteins, phosphoinositides, and sugar nucleotide supply, have been implicated in the regulation of cell wall biosynthesis or deposition. In the past two years, there have been important discoveries in transcriptional regulation of secondary wall biosynthesis. Several transcription factors in the NAC and MYB families have been shown to be the key switches for activation of secondary wall biosynthesis. These studies suggest a transcriptional network comprised of a hierarchy of transcription factors is involved in regulating secondary wall biosynthesis. Further investigation and integration of the regulatory players participating in the making of cell walls will certainly lead to our understanding of how wall amounts and composition are controlled in a given cell type. This may eventually allow custom design of plant cell walls on the basis of our needs.

Plant cell wall extensibility: connecting plant cell growth with cell wall structure, mechanics, and the action of wall-modifying enzymes

Energy Technology Data Exchange (ETDEWEB)

Cosgrove, Daniel J.

2015-11-25

The advent of user-friendly instruments for measuring force/deflection curves of plant surfaces at high spatial resolution has resulted in a recent outpouring of reports of the ‘Young's modulus’ of plant cell walls. The stimulus for these mechanical measurements comes from biomechanical models of morphogenesis of meristems and other tissues, as well as single cells, in which cell wall stress feeds back to regulate microtubule organization, auxin transport, cellulose deposition, and future growth directionality. In this article I review the differences between elastic modulus and wall extensibility in the context of cell growth. Some of the inherent complexities, assumptions, and potential pitfalls in the interpretation of indentation force/deflection curves are discussed. Reported values of elastic moduli from surface indentation measurements appear to be 10- to >1000-fold smaller than realistic tensile elastic moduli in the plane of plant cell walls. Potential reasons for this disparity are discussed, but further work is needed to make sense of the huge range in reported values. The significance of wall stress relaxation for growth is reviewed and connected to recent advances and remaining enigmas in our concepts of how cellulose, hemicellulose, and pectins are assembled to make an extensible cell wall. A comparison of the loosening action of α-expansin and Cel12A endoglucanase is used to illustrate two different ways in which cell walls may be made more extensible and the divergent effects on wall mechanics.

Effects of dietary cadmium on growth, antioxidants and bioaccumulation of sea cucumber (Apostichopus japonicus) and influence of dietary vitamin C supplementation.

Science.gov (United States)

Wang, Jing; Ren, Tongjun; Wang, Fuqiang; Han, Yuzhe; Liao, Mingling; Jiang, Zhiqiang; Liu, Haiying

2016-07-01

The effects of dietary cadmium (Cd) supplementation on growth, antioxidant capacity and accumulation of Cd in tissues (body wall, digestive tracts, and respiratory tree) of sea cucumber, Apostichopus japonicus, exposed to sub-chronic concentrations (0, 10, 50, 100, and 500mg Cd/kg dry weight) of Cd were investigated. In addition, the potential protective effects of vitamin C (L-ascorbic acid, AsA) against the effects of Cd on sea cucumbers were investigated. Sea cucumbers were exposed to dietary Cd for 30 days, after which another group of healthy sea cucumbers was supplied diet supplemented with mixed Cd and AsA for another 30 days. Cd exposure for 30 days resulted in increased Cd accumulation in tissues of sea cucumbers with exposure time and concentration. The order of Cd accumulation in organs was digestive tracts>respiratory tree>body wall. On day 30, the body weight gain (BWG) and specific growth rate (SGR) decreased significantly (Psea cucumbers decreased with increasing dietary Cd concentration, but malondialdehyde (MDA) content in the coelomic fluid increased. Providing diet supplemented with Cd and AsA indicated that although sea cucumbers exhibited signs of Cd toxicity, no death occurred in response to 50mg Cd/kg for 30 days. Based on these findings, five treatments were provided: 50mg Cd/kg+0mg AsA/kg, 50mg Cd/kg+ 3000mg AsA/kg, 50mg Cd/kg+ 5000mg AsA/kg, 50mg Cd/kg+10,000mg AsA/kg, and 50mg Cd/kg+15,000mg AsA/kg. The BWG and SGR of sea cucumbers fed the AsA supplemented diet mixed with Cd increased. Additionally, MDA levels in coelomic fluid were negatively correlated with dietary AsA levels, while antioxidant capacities (SOD, GSH-Px and CAT) were positively correlated with dietary AsA levels. Moreover, Cd accumulation in tissues decreased in response to dietary AsA supplementation of treatments. Overall, antioxidant capacity and bioaccumulation in sea cucumber was found to decrease and be induced in response to Cd, but vitamin C mitigated these

Critical Beach Habitat for Hawaiian Green Sea Turtle Endangered Before Mid-Century

Science.gov (United States)

Burstein, J. T.; Fletcher, C. H., III; Dominique Tavares, K.

2017-12-01

Many Hawaiian beaches provide critical habitat for the Hawaiian Green Sea Turtle (Chelonia Mydas). However, sea level rise drives beaches and dunes to migrate landward where they may encounter roads and other types of developed lands. Where developed lands are threatened by coastal erosion, defined as a distance of 20 ft (6.1 m) by state rules, property owners are eligible to apply for an emergency permit. These have historically led to coastal armoring. Seawalls and revetments on chronically receding shorelines cause permanent beach loss by restricting sand supply to the beach in front of the sea wall, as well as to beaches adjacent to the restrictive structure (flanking). This study focuses on four primary beach habitats along the North Shore of Oahu, Hawai'i: Waimea, Haleiwa, Kawailoa, and Mokuleia. We utilize GIS techniques to apply spatial analysis of nesting and basking locations collected from the National Oceanic Atmospheric Administration (NOAA). We then estimate the number of homes and the length of shoreline threatened by coastal armoring for 0 m, 0.17 m, 0.32 m, 0.60 m, and 0.98 m of sea-level rise. We demonstrate that 0.17 m of sea level rise impacts 31% of all beach front homes, and 4.6 km of shoreline, or 21% of the total shoreline. An increase to 0.32 m of sea level rise impacts 42% of all beach front homes, and 5.8 km of shoreline, or 31% of the total shoreline. The upper bound of the most recent sea level rise projection by the International Panel on Climate Change (IPCC RCP 8.5) affirms that 0.17 m of sea level rise may be reached by 2030, and 0.32 m by 2050. This sea level projection is a "worst-case" under IPCC-AR5, however, Sweet et al. (2017) depicts this as an "Intermediate" scenario on the basis of faster than expected mass loss by Greenland and Antarctica ice sheets, and rapid heat uptake and thermal expansion by the world's oceans. We conclude that the impacts of sea level rise and reactive coastal armoring currently endanger critical

Abdominal wall fat pad biopsy

Science.gov (United States)

Amyloidosis - abdominal wall fat pad biopsy; Abdominal wall biopsy; Biopsy - abdominal wall fat pad ... is the most common method of taking an abdominal wall fat pad biopsy . The health care provider cleans the ...

Spontaneous and controlled-diameter synthesis of single-walled and few-walled carbon nanotubes

Science.gov (United States)

Inoue, Shuhei; Lojindarat, Supanat; Kawamoto, Takahiro; Matsumura, Yukihiko; Charinpanitkul, Tawatchai

2018-05-01

In this study, we explored the spontaneous and controlled-diameter growth of carbon nanotubes. We evaluated the effects of catalyst density, reduction time, and a number of catalyst coating on the substrate (for multi-walled carbon nanotubes) on the diameter of single-walled carbon nanotubes and the number of layers in few-walled carbon nanotubes. Increasing the catalyst density and reduction time increased the diameters of the carbon nanotubes, with the average diameter increasing from 1.05 nm to 1.86 nm for single-walled carbon nanotubes. Finally, we succeeded in synthesizing a significant double-walled carbon nanotube population of 24%.

Regulation of Cell Wall Biogenesis in Saccharomyces cerevisiae: The Cell Wall Integrity Signaling Pathway

Science.gov (United States)

Levin, David E.

2011-01-01

The yeast cell wall is a strong, but elastic, structure that is essential not only for the maintenance of cell shape and integrity, but also for progression through the cell cycle. During growth and morphogenesis, and in response to environmental challenges, the cell wall is remodeled in a highly regulated and polarized manner, a process that is principally under the control of the cell wall integrity (CWI) signaling pathway. This pathway transmits wall stress signals from the cell surface to the Rho1 GTPase, which mobilizes a physiologic response through a variety of effectors. Activation of CWI signaling regulates the production of various carbohydrate polymers of the cell wall, as well as their polarized delivery to the site of cell wall remodeling. This review article centers on CWI signaling in Saccharomyces cerevisiae through the cell cycle and in response to cell wall stress. The interface of this signaling pathway with other pathways that contribute to the maintenance of cell wall integrity is also discussed. PMID:22174182

Orbital wall fractures

International Nuclear Information System (INIS)

Iinuma, Toshitaka; Ishio, Ken-ichirou; Yoshinami, Hiroyoshi; Kuriyama, Jun-ichi; Hirota, Yoshiharu.

1993-01-01

A total of 59 cases of mild facial fractures (simple orbital wall fractures, 34 cases, other facial fractures, 25 cases) with the clinical suspects of orbital wall fractures were evaluated both by conventional views (Waters' and Caldwell views) and coronal CT scans. Conventional views were obtained, as an average, after 4 days and CT after 7 days of injuries. Both the medial wall and the floor were evaluated at two sites, i.e., anterior and posterior. The ethmoid-maxillary plate was also included in the study. The degree of fractures was classified as, no fractures, fractures of discontinuity, dislocation and fragmentation. The coronal CT images in bone window condition was used as reference and the findings were compared between conventional views and CT. The correct diagnosis was obtained as follows: orbital floor (anterior, 78%, posterior, 73%), medial orbital wall (anterior, 72%, posterior, 72%) and ethmoid-maxillary plate (64%). The false positive diagnosis was as follows: orbital floor (anterior only, 13%), medial orbital wall (anterior only, 7%) and ethmoid-maxillary plate (11%). The false negative diagnosis was as follows: orbital floor (anterior, 9%, posterior, 10%), medial orbital wall (anterior, 21%, posterior, 28%) and ethmoid-maxillary plate (21%). The results were compared with those of others in the past. (author)

PREFACE: Domain wall dynamics in nanostructures Domain wall dynamics in nanostructures

Science.gov (United States)

Marrows, C. H.; Meier, G.

2012-01-01

Domain structures in magnetic materials are ubiquitous and have been studied for decades. The walls that separate them are topological defects in the magnetic order parameter and have a wide variety of complex forms. In general, their investigation is difficult in bulk materials since only the domain structure on the surface of a specimen is visible. Cutting the sample to reveal the interior causes a rearrangement of the domains into a new form. As with many other areas of magnetism, the study of domain wall physics has been revitalised by the advent of nanotechnology. The ability to fabricate nanoscale structures has permitted the formation of simplified and controlled domain patterns; the development of advanced microscopy methods has permitted them to be imaged and then modelled; subjecting them to ultrashort field and current pulses has permitted their dynamics to be explored. The latest results from all of these advances are described in this special issue. Not only has this led to results of great scientific beauty, but also to concepts of great applicability to future information technologies. In this issue the reader will find the latest results for these domain wall dynamics and the high-speed processes of topological structures such as domain walls and magnetic vortices. These dynamics can be driven by the application of magnetic fields, or by flowing currents through spintronic devices using the novel physics of spin-transfer torque. This complexity has been studied using a wide variety of experimental techniques at the edge of the spatial and temporal resolution currently available, and can be described using sophisticated analytical theory and computational modelling. As a result, the dynamics can be engineered to give rise to finely controlled memory and logic devices with new functionality. Moreover, the field is moving to study not only the conventional transition metal ferromagnets, but also complex heterostructures, novel magnets and even other

Construction works of large scale impervious wall in construction of No.2 plant in Onagawa Nuclear Power Station, Tohoku Electric Power Co., Inc

International Nuclear Information System (INIS)

Ueda, Kozaburo; Sugeno, Yoshisada; Takahashi, Hitoshi

1991-01-01

The main buildings for No. 2 plant in Onagawa Nuclear Power Station are constructed on the bedrocks about 14 m below the sea surface. Therefore, for the purpose of executing the works by shutting seawater off and dry work, the large scale impervious wall of about 500 m extension was installed underground. The feature of this impervious wall is the depth of embedment of about 3 m into the hard bedrocks having the uniaxial compressive strength of 2000 kg/cm 2 at maximum, carried out with the newly developed hard rock excavator. The outline of these construction works is reported. No. 2 plant in Onagawa Nuclear Power Station is the BWR plant of 825 MWe output. The construction works of the power station were began in August, 1989, and the rate of progress in civil engineering works as of the end of September, 1990 was 21.3%. The planning of the impervious wall, the geological features at the site, the method of shutting seawater off, the selection of wall materials, the design of the wall body, the investigation of the quantity of spring water, the execution of the construction and execution management, and the confirmation of the effect of the wall are reported. (K.I.)

Electroweak bubble wall speed limit

Energy Technology Data Exchange (ETDEWEB)

Bödeker, Dietrich [Fakultät für Physik, Universität Bielefeld, 33501 Bielefeld (Germany); Moore, Guy D., E-mail: bodeker@physik.uni-bielefeld.de, E-mail: guymoore@ikp.physik.tu-darmstadt.de [Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 2, 64289 Darmstadt (Germany)

2017-05-01

In extensions of the Standard Model with extra scalars, the electroweak phase transition can be very strong, and the bubble walls can be highly relativistic. We revisit our previous argument that electroweak bubble walls can 'run away,' that is, achieve extreme ultrarelativistic velocities γ ∼ 10{sup 14}. We show that, when particles cross the bubble wall, they can emit transition radiation. Wall-frame soft processes, though suppressed by a power of the coupling α, have a significance enhanced by the γ-factor of the wall, limiting wall velocities to γ ∼ 1/α. Though the bubble walls can move at almost the speed of light, they carry an infinitesimal share of the plasma's energy.

The effect of partial poloidal wall sections on the wall stabilization of external kink modes

International Nuclear Information System (INIS)

Ward, D.J.

1996-02-01

An analysis of the effect on the wall stabilization of external kink modes due to toroidally continuous gaps in the resistive wall is performed. The effects with and without toroidal rotation are studied. For a high-β equilibrium, the mode structure is localized on the outboard side. Therefore, outboard gaps greatly increase the growth rate when there is no rotation. For resistive wall stabilization by toroidal rotation, the presence of gaps has the same effect as moving the wall farther away, i.e. destabilizing for the ideal plasma mode, and stabilizing for the resistive wall mode. The region of stability, in terms of wall position, is reduced in size and moved closer to the plasma. However, complete stabilization becomes possible at considerably reduced rotation frequencies. For a high-β, reverse-shear equilibrium both the resistive wall mode and the ideal plasma mode can be stabilized by close fitting discrete passive plates on the outboard side. The necessary toroidal rotation frequency to stabilize the resistive wall mode using these plates is reduced by a factor of three compared to that for a poloidally continuous and complete wall at the same plasma-wall separation. (author) 15 figs., 24 refs

A Structurally Specialized Uniform Wall Layer is Essential for Constructing Wall Ingrowth Papillae in Transfer Cells

Science.gov (United States)

Xia, Xue; Zhang, Hui-Ming; Offler, Christina E.; Patrick, John W.

2017-01-01

Transfer cells are characterized by wall labyrinths with either a flange or reticulate architecture. A literature survey established that reticulate wall ingrowth papillae ubiquitously arise from a modified component of their wall labyrinth, termed the uniform wall layer; a structure absent from flange transfer cells. This finding sparked an investigation of the deposition characteristics and role of the uniform wall layer using a Vicia faba cotyledon culture system. On transfer of cotyledons to culture, their adaxial epidermal cells spontaneously trans-differentiate to a reticulate architecture comparable to their abaxial epidermal transfer cell counterparts formed in planta. Uniform wall layer construction commenced once adaxial epidermal cell expansion had ceased to overlay the original outer periclinal wall on its inner surface. In contrast to the dense ring-like lattice of cellulose microfibrils in the original primary wall, the uniform wall layer was characterized by a sparsely dispersed array of linear cellulose microfibrils. A re-modeled cortical microtubule array exerted no influence on uniform wall layer formation or on its cellulose microfibril organization. Surprisingly, formation of the uniform wall layer was not dependent upon depositing a cellulose scaffold. In contrast, uniform wall cellulose microfibrils were essential precursors for constructing wall ingrowth papillae. On converging to form wall ingrowth papillae, the cellulose microfibril diameters increased 3-fold. This event correlated with up-regulated differential, and transfer-cell specific, expression of VfCesA3B while transcript levels of other cellulose biosynthetic-related genes linked with primary wall construction were substantially down-regulated. PMID:29259611

Shear localization and effective wall friction in a wall bounded granular flow

Science.gov (United States)

Artoni, Riccardo; Richard, Patrick

2017-06-01

In this work, granular flow rheology is investigated by means of discrete numerical simulations of a torsional, cylindrical shear cell. Firstly, we focus on azimuthal velocity profiles and study the effect of (i) the confining pressure, (ii) the particle-wall friction coefficient, (iii) the rotating velocity of the bottom wall and (iv) the cell diameter. For small cell diameters, azimuthal velocity profiles are nearly auto-similar, i.e. they are almost linear with the radial coordinate. Different strain localization regimes are observed : shear can be localized at the bottom, at the top of the shear cell, or it can be even quite distributed. This behavior originates from the competition between dissipation at the sidewalls and dissipation in the bulk of the system. Then we study the effective friction at the cylindrical wall, and point out the strong link between wall friction, slip and fluctuations of forces and velocities. Even if the system is globally below the sliding threshold, force fluctuations trigger slip events, leading to a nonzero wall slip velocity and an effective wall friction coefficient different from the particle-wall one. A scaling law was found linking slip velocity, granular temperature in the main flow direction and effective friction. Our results suggest that fluctuations are an important ingredient for theories aiming to capture the interface rheology of granular materials.

Last Interglacial (Eemian) hydrographic conditions in the south-eastern Baltic Sea, NE Europe, based on dinoflagellates and pollen

DEFF Research Database (Denmark)

Head, Martin J.; Seidenkrantz, Marit Solveig Louise Schramm; Janczyk-Kopikowa, Zofia

2005-01-01

of arctic waters. Warm and saline conditions of 15–20 psu or more, at least twice present levels, persisted throughout the early Eemian. A rise in sea level at Licze appears to correlate with a similar event in eastern Denmark, as both coincide with the increase in Corylus (ca. 750 years...... into the interglacial). This sea-level rise might therefore have a basinwide extent, and has been attributed to an opening of the Danish Belts. Whereas dinoflagellate cysts reflect sustained high salinites within the upper water column, a concomitant increase in abundance of the chlorococcalean alga Pediastrum within......A rich organic-walled dinoflagellate cyst and pollen record from the Licze borehole in northern Poland has been used to reconstruct the hydrographic history of the southeastern Baltic Sea during the Eemian Stage (Last Interglacial) of the Upper Pleistocene. Warm and saline waters (ca. 10–15 psu...

Climatology of sea breezes along the Red Sea coast of Saudi Arabia

KAUST Repository

Khan, Basit

2018-04-25

Long-term near-surface observations from five coastal stations, high-resolution model data from Modern Era Retrospective-Analysis for Research and Applications (MERRA) and high-resolution daily sea surface temperature (SST) from National Ocean and Atmospheric Administration (NOAA) are used to investigate the climatology of sea breezes over the eastern side of the Red Sea region. Results show existence of separate sea breeze systems along different segments of the Red Sea coastline. Based on the physical character and synoptic influences, sea breezes in the Red Sea are broadly divided into three regions: the north and the middle Red Sea (NMRS), the Red Sea convergence zone (RSCZ) and the southern Red Sea (SRS) regions. On average, sea breezes developed on 67% of days of the 10-year study period. Although sea breezes occur almost all year, this mesoscale phenomenon is most frequent from May to October (78% of the total sea breeze days). The sea breeze frequency increases from north to south (equatorwards), and sea breeze characteristics appear to vary both temporally and spatially. In addition to land-sea thermal differential, coastline shape, latitude and topography, the prevailing northwesterly at NMRS region, the convergence of northwesterly and southeasterly wind system at RSCZ region and the northeast and southwest monsoon at SRS region play an important role in defining the sea breeze characteristics over the Red Sea.

The role of wall calcium in the extension of cell walls of soybean hypocotyls

Science.gov (United States)

Virk, S. S.; Cleland, R. E.

1990-01-01

Calcium crosslinks are load-bearing bonds in soybean (Glycine max (L.) Merr.) hypocotyl cell walls, but they are not the same load-bearing bonds that are broken during acid-mediated cell elongation. This conclusion is reached by studying the relationship between wall calcium, pH and the facilitated creep of frozen-thawed soybean hypocotyl sections. Supporting data include the following observations: 1) 2-[(2-bis-[carboxymethyl]amino-5-methylphenoxy)methyl]-6-methoxy-8-bis[car boxymethyl]aminoquinoline (Quin 2) and ethylene glycol-bis(2-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) caused only limited facilitated creep as compared with acid, despite removal of comparable or larger amounts of wall calcium; 2) the pH-response curves for calcium removal and acid-facilitated creep were different; 3) reversible acid-extension occurred even after removal of almost all wall calcium with Quin 2; and 4) growth of abraded sections did not involve a proportional loss of wall calcium. Removal of wall calcium, however, increased the capacity of the walls to undergo acid-facilitated creep. These data indicate that breakage of calcium crosslinks is not a major mechanism of cell-wall loosening in soybean hypocotyl tissues.

Intraseasonal sea surface temperature variability in Indonesian seas

Science.gov (United States)

Napitu, A. M.; Gordon, A. L.; Yuan, X.

2012-12-01

The satellite-derived sea surface temperature (SST) data, 1998-mid 2012, are used to examine intraseasonal variability (ISV; 20-90 days) across the Indonesian seas. The most energetic ISV is observed in the Banda Sea and across the Indo-Australia basin with an The satellite-derived sea surface temperature (SST) data, 1998-mid 2012, are used to examine intraseasonal variability (ISV; 20-90 days) across the Indonesian seas. The most energetic ISV is observed in the Banda Sea and across the Indo-Australia basin with an average SST standard deviation (STD) between 0.4-0.5°C, with strongest signature during boreal winter. What physical processes force the SST ISV variability within the Indonesian seas? Ocean process, sea-air interaction, or both? To help identify the main forcing, the satellite derived outgoing longwave radiation (OLR) and wind stress data in the region are examined. The OLR shows robust intraseasonal variations and is significantly correlated with the SST, particularly for variability with periods of 30-60 days, with OLR accounting for ~60-70% of the SST variance. The OLR is also maximum during boreal winter. Conversely, the surface wind may play insignificant role in perturbing the SST at intraseasonal timescales as shown by weak correlation between wind stress and SST. We thus suspect that the surface solar flux (suggested by the OLR) is likely more dominant than the surface turbulent heat flux (indicated by the surface wind) as the main source for the ISV in the SST in Indonesian seas. Furthermore the maximum OLR phase, coupled with a period of minimum mixed layer depth, may explain the strong SST variation during boreal winter in Indonesian seas. The influence of the Madden-Julian Oscillation (MJO) on the OLR and SST variability is currently being evaluated.

Ultrastructural and Molecular Characterisation of an Heterosporis-Like Microsporidian in Australian Sea Snakes (Hydrophiinae.

Directory of Open Access Journals (Sweden)

Amber K Gillett

Full Text Available Four sea snakes (two Hydrophis major, one Hydrophis platurus, one Hydrophis elegans were found washed ashore on different beaches in the Sunshine Coast region and Fraser Island in Queensland, Australia between 2007-2013. Each snake had multiple granulomas and locally extensive regions of pallor evident in the hypaxial and intercostal musculature along the body. Lesions in two individuals were also associated with vertebral and rib fractures. Histological examination revealed granulomas scattered throughout skeletal muscle, subcutaneous adipose tissue and fractured bone. These were composed of dense aggregates of microsporidian spores surrounded by a mantle of macrophages. Sequences (ssrRNA were obtained from lesions in three sea snakes and all revealed 99% similarity with Heterosporis anguillarum from the Japanese eel (Anguillarum japonica. However, ultrastructural characteristics of the organism were not consistent with those of previous descriptions. Electron microscopic examination of skeletal muscle revealed large cysts (not xenomas bound by walls of fibrillar material (Heterosporis-like sporophorocyst walls were not detected. The cysts contained numerous mature microsporidian spores arranged in small clusters, sometimes apparently within sporophorous vesicles. The microspores were monomorphic, oval and measured 2.5-3.0 μm by 1.6-1.8 μm. They contained isofilar polar filaments with 11 (infrequently 9-12 coils arranged in two ranks. This is the first published report of a microsporidian infection in hydrophiid sea snakes. This discovery shows microsporidia with molecular affinities to Heterosporis anguillarum but ultrastructural characters most consistent with the genus Pleistophora (but no hitherto described species. Further studies are required to determine whether the microsporidian presented here belongs to the genus Heterosporis, or to a polymorphic species group as suggested by the recognition of a robust Pleistophora

A new species of Havelockia Pearson, 1903 from the Argentine Sea (Holothuroidea: Dendrochirotida: Sclerodactylidae).

Science.gov (United States)

Martinez, Mariano I; Thandar, Ahmed S; Penchaszadeh, Pablo E

2013-02-04

Havelockia pegi sp. nov., is here described from shallow waters of the Argentine Sea. This new species is distinctive in the purple colouration of its tentacles, scarcity of body wall ossicles and the presence of rosette-shaped ossicles in both the introvert and the tentacles. It is not closely related to any of its congenors. This is the first record of a true sclerodactylid from Argentina. Thandarum hernandezi Martinez & Brogger, 2012, described in the family Sclerodactylidae, is now classified in the family Sclerothyonidae.

Granular packings with moving side walls

International Nuclear Information System (INIS)

Landry, James W.; Grest, Gary Stephen

2004-01-01

The effects of movement of the side walls of a confined granular packing are studied by discrete element, molecular dynamics simulations. The dynamical evolution of the stress is studied as a function of wall movement both in the direction of gravity as well as opposite to it. For all wall velocities explored, the stress in the final state of the system after wall movement is fundamentally different from the original state obtained by pouring particles into the container and letting them settle under the influence of gravity. The original packing possesses a hydrostaticlike region at the top of the container which crosses over to a depth-independent stress. As the walls are moved in the direction opposite to gravity, the saturation stress first reaches a minimum value independent of the wall velocity, then increases to a steady-state value dependent on the wall velocity. After wall movement ceases and the packing reaches equilibrium, the stress profile fits the classic Janssen form for high wall velocities, while some deviations remain for low wall velocities. The wall movement greatly increases the number of particle-wall and particle-particle forces at the Coulomb criterion. Varying the wall velocity has only small effects on the particle structure of the final packing so long as the walls travel a similar distance.

Antithrombotic activities of fucosylated chondroitin sulfates and their depolymerized fragments from two sea cucumbers.

Science.gov (United States)

Liu, Xiaoxiao; Hao, Jiejie; Shan, Xindi; Zhang, Xiao; Zhao, Xiaoliang; Li, Qinying; Wang, Xiaojiang; Cai, Chao; Li, Guoyun; Yu, Guangli

2016-11-05

Fucosylated chondroitin sulfate (FCS), a glycosaminoglycan extracted from the body wall of sea cucumber, is a promising antithrombotic agent. The chemical structures of FCSc isolated from sea cucumber Cucumaria frondosa and its depolymerized fragment (dFCSc) were characterized for the first time. Additionally, anticoagulant and antithrombotic activities were evaluated in vitro and in vivo. The results demonstrated that dFCSc exhibited better antithrombotic-hemorrhagic ratio than native FCSc on the electrical induced arterial thrombosis model in rats. Compared to FCSt obtained from Thelenota ananas, FCSc possessed different sulfation patterns but similar antithrombotic effects. Therefore, sulfation pattern of FCS might not affect anticoagulation and antithrombosis as much as molecular weight may. Our results proposed a new point of view to understand the structure-activity relationship of FCS as alternative agents. Copyright © 2016 Elsevier Ltd. All rights reserved.

First discovery of a cold seep on the continental margin of the central Red Sea

KAUST Repository

Batang, Zenon B.

2012-06-01

A new cold brine seep system with microbial mats and metazoan assemblages was discovered by a remotely operated vehicle (ROV) on the Saudi continental margin of central Red Sea. Now named as Thuwal Seeps, it has a shallow brine pool between 840 and 850. m water depths that is formed by focused brine expulsions from two sites (Seep I: 22°17.3\\'N, 38°53.8\\'E; Seep II: 22°16.9\\'N, 38°53.9\\'E). The seep is located at the base of a steep wall rock closer to the shore (20. km) than to the axial trough (120. km). The brine pool does not exhibit a significant thermal anomaly (<. 0.3°C) and is so far the coldest (21.7°C) and least saline (74‰) among brine pools in the Red Sea. This discovery provides the first direct evidence of a cold seep with associated biota on the continental margin of the Red Sea. © 2011 Elsevier B.V.

Plasma-wall interactions

International Nuclear Information System (INIS)

Behrisch, Rainer

1978-01-01

The plasma wall interactions for two extreme cases, the 'vacuum model' and the 'cold gas blanket' are outlined. As a first step for understanding the plasma wall interactions the elementary interaction processes at the first wall are identified. These are energetic ion and neutral particle trapping and release, ion and neutral backscattering, ion sputtering, desorption by ions, photons and electrons and evaporation. These processes have only recently been started to be investigated in the parameter range of interest for fusion research. The few measured data and their extrapolation into regions not yet investigated are reviewed

Sea-ice evaluation of NEMO-Nordic 1.0: a NEMO-LIM3.6-based ocean-sea-ice model setup for the North Sea and Baltic Sea

Science.gov (United States)

Pemberton, Per; Löptien, Ulrike; Hordoir, Robinson; Höglund, Anders; Schimanke, Semjon; Axell, Lars; Haapala, Jari

2017-08-01

The Baltic Sea is a seasonally ice-covered marginal sea in northern Europe with intense wintertime ship traffic and a sensitive ecosystem. Understanding and modeling the evolution of the sea-ice pack is important for climate effect studies and forecasting purposes. Here we present and evaluate the sea-ice component of a new NEMO-LIM3.6-based ocean-sea-ice setup for the North Sea and Baltic Sea region (NEMO-Nordic). The setup includes a new depth-based fast-ice parametrization for the Baltic Sea. The evaluation focuses on long-term statistics, from a 45-year long hindcast, although short-term daily performance is also briefly evaluated. We show that NEMO-Nordic is well suited for simulating the mean sea-ice extent, concentration, and thickness as compared to the best available observational data set. The variability of the annual maximum Baltic Sea ice extent is well in line with the observations, but the 1961-2006 trend is underestimated. Capturing the correct ice thickness distribution is more challenging. Based on the simulated ice thickness distribution we estimate the undeformed and deformed ice thickness and concentration in the Baltic Sea, which compares reasonably well with observations.

Sea level report

International Nuclear Information System (INIS)

Schwartz, M.L.

1979-01-01

Study of Cenozoic Era sea levels shows a continual lowering of sea level through the Tertiary Period. This overall drop in sea level accompanied the Pleistocene Epoch glacio-eustatic fluctuations. The considerable change of Pleistocene Epoch sea level is most directly attributable to the glacio-eustatic factor, with a time span of 10 5 years and an amplitude or range of approximately 200 m. The lowering of sea level since the end of the Cretaceous Period is attributed to subsidence and mid-ocean ridges. The maximum rate for sea level change is 4 cm/y. At present, mean sea level is rising at about 3 to 4 mm/y. Glacio-eustacy and tectono-eustacy are the parameters for predicting sea level changes in the next 1 my. Glacio-eustatic sea level changes may be projected on the basis of the Milankovitch Theory. Predictions about tectono-eustatic sea level changes, however, involve predictions about future tectonic activity and are therefore somewhat difficult to make. Coastal erosion and sedimentation are affected by changes in sea level. Erosion rates for soft sediments may be as much as 50 m/y. The maximum sedimentation accumulation rate is 20 m/100 y

Dynamic wall demonstration project

Energy Technology Data Exchange (ETDEWEB)

Nakatsui, L.; Mayhew, W.

1990-12-01

The dynamic wall concept is a ventilation strategy that can be applied to a single family dwelling. With suitable construction, outside air can be admitted through the exterior walls of the house to the interior space to function as ventilation air. The construction and performance monitoring of a demonstration house built to test the dynamic wall concept in Sherwood Park, Alberta, is described. The project had the objectives of demonstrating and assessing the construction methods; determining the cost-effectiveness of the concept in Alberta; analyzing the operation of the dynamic wall system; and determining how other components and systems in the house interact with the dynamic wall. The exterior wall construction consisted of vinyl siding, spun-bonded polyolefin-backed (SBPO) rigid fiberglass sheathing, 38 mm by 89 mm framing, fiberglass batt insulation and 12.7 mm drywall. The mechanical system was designed to operate in the dynamic (negative pressure) mode, however flexibility was provided to allow operation in the static (balanced pressure) mode to permit monitoring of the walls as if they were in a conventional house. The house was monitored by an extensive computerized monitoring system. Dynamic wall operation was dependent on pressure and temperature differentials between indoor and outdoor as well as wind speed and direction. The degree of heat gain was found to be ca 74% of the indoor-outdoor temperature differential. Temperature of incoming dynamic air was significantly affected by solar radiation and measurement of indoor air pollutants found no significant levels. 4 refs., 34 figs., 11 tabs.

Enhanced wall pumping in JET

International Nuclear Information System (INIS)

Ehrenberg, J.; Harbour, P.J.

1991-01-01

The enhanced wall pumping phenomenon in JET is observed for hydrogen or deuterium plasmas which are moved from the outer (larger major radius) limiter position either to the inner wall or to the top/bottom wall of the vacuum vessel. This phenomenon is analysed by employing a particle recycling model which combines plasma particle transport with particle re-emission from and retention within material surfaces. The model calculates the important experimentally observable quantities, such as particle fluxes, global particle confinement time, plasma density and density profile. Good qualitative agreement is found and, within the uncertainties, the agreement is quantitative if the wall pumping is assumed to be caused by two simultaneously occurring effects: (1) Neutral particle screening at the inner wall and the top/bottom wall is larger than that at the outer limiter because of different magnetic topologies at different poloidal positions; and (2) although most of the particles (≥ 90%) impacting on the wall can be promptly re-emitted, a small fraction (≤ 10%) of them must be retained in the wall for a period of time which is similar to or larger than the global plasma particle confinement time. However, the wall particle retention time need not be different from that of the outer limiter, i.e. pumping can occur when there is no difference between the material properties of the limiter and those of the wall. (author). 45 refs, 18 figs

Fuel retention under elevated wall temperature in KSTAR with a carbon wall

Science.gov (United States)

Cao, B.; Hong, S. H.

2018-03-01

The fuel retention during KSTAR discharges with elevated wall temperature (150 °C) has been studied by using the method of global particle balance. The results show that the elevated wall temperature could reduce the dynamic retention via implantation and absorption, especially for the short pulse shots with large injected fuel particles. There is no signature changing of long-term retention, which related to co-deposition, under elevated wall temperature. For soft-landing shots (normal shots), the exhausted fuel particles during discharges is larger with elevated wall temperature than without, but the exhausted particles after discharges within 90 s looks similar. The outgassing particles because of disruption could be exhausted within 15 s.

The wind sea and swell waves climate in the Nordic seas

Science.gov (United States)

Semedo, Alvaro; Vettor, Roberto; Breivik, Øyvind; Sterl, Andreas; Reistad, Magnar; Soares, Carlos Guedes; Lima, Daniela

2015-02-01

A detailed climatology of wind sea and swell waves in the Nordic Seas (North Sea, Norwegian Sea, and Barents Sea), based on the high-resolution reanalysis NORA10, developed by the Norwegian Meteorological Institute, is presented. The higher resolution of the wind forcing fields, and the wave model (10 km in both cases), along with the inclusion of the bottom effect, allowed a better description of the wind sea and swell features, compared to previous global studies. The spatial patterns of the swell-dominated regional wave fields are shown to be different from the open ocean, due to coastal geometry, fetch dimensions, and island sheltering. Nevertheless, swell waves are still more prevalent and carry more energy in the Nordic Seas, with the exception of the North Sea. The influence of the North Atlantic Oscillation on the winter regional wind sea and swell patterns is also presented. The analysis of the decadal trends of wind sea and swell heights during the NORA10 period (1958-2001) shows that the long-term trends of the total significant wave height (SWH) in the Nordic Seas are mostly due to swell and to the wave propagation effect.

Diets containing sea cucumber (Isostichopus badionotus meals are hypocholesterolemic in young rats.

Directory of Open Access Journals (Sweden)

Leticia Olivera-Castillo

Full Text Available Sea cucumber is widely consumed as a putative functional food. It contains many biologically-active substances, but only limited research on its properties in vivo has been done. The effects of different meals containing Isostichopus badionotus, a sea cucumber from southeast Mexico, on growth performance and body lipid profile in young rats were analyzed. Sea cucumber body wall was either lyophilized, cooked (100 °C, 1 h in water and lyophilized, or oven-dried (70 °C for 12 h. It was then ground and incorporated into cholesterol-containing diets. I. badionotus meals supported growth and improved lipid profile in rats. In particular, serum cholesterol, low density lipoproteins, triglycerides concentration and atherogenic index values were greatly reduced by some I. badionotus containing diets. Liver total lipids, triglycerides and cholesterol were also reduced. Cooking or heat-treatment of the meals lowered but did not abolish their hypolipidemic potency. Gene expression analysis of several key genes involved in cholesterol and lipid metabolism in liver showed that diets containing I. badionotus repressed the induction of key genes associated with dyslipidemia exerted by cholesterol supplementation. Consumption of I. badionotus from the Yucatan Peninsula is beneficial for dyslipidemia, although biological effect is clearly dependent on preparation method.

International Divider Walls

NARCIS (Netherlands)

Kruis, A.; Sneller, Lineke

2013-01-01

The subject of this teaching case is the Enterprise Resource Planning (ERP) system implementation at International Divider Walls, the world market leader in design, production, and sales of divider walls. The implementation in one of the divisions of this multinational company had been successful,

Investigating Arctic Sea Ice Survivability in the Beaufort Sea

Directory of Open Access Journals (Sweden)

Matthew Tooth

2018-02-01

Full Text Available Arctic sea ice extent has continued to decline in recent years, and the fractional coverage of multi-year sea ice has decreased significantly during this period. The Beaufort Sea region has been the site of much of the loss of multi-year sea ice, and it continues to play a large role in the extinction of ice during the melt season. We present an analysis of the influence of satellite-derived ice surface temperature, ice thickness, albedo, and downwelling longwave/shortwave radiation as well as latitude and airborne snow depth estimates on the change in sea ice concentration in the Beaufort Sea from 2009 to 2016 using a Lagrangian tracking database. Results from this analysis indicate that parcels that melt during summer in the Beaufort Sea reside at lower latitudes and have lower ice thickness at the beginning of the melt season in most cases. The influence of sea ice thickness and snow depth observed by IceBridge offers less conclusive results, with some years exhibiting higher thicknesses/depths for melted parcels. Parcels that melted along IceBridge tracks do exhibit lower latitudes and ice thicknesses, however, which indicates that earlier melt and breakup of ice may contribute to a greater likelihood of extinction of parcels in the summer.

Wall Street som kreationistisk forkynder

DEFF Research Database (Denmark)

Ekman, Susanne

2016-01-01

Artiklen gennemgår Karen Hos etnografi om Wall Street: "Liquidated: An ethnography of Wall Street" set i lyset af den offentlige debat vedrørende Goldman Sachs opkøb af Dong......Artiklen gennemgår Karen Hos etnografi om Wall Street: "Liquidated: An ethnography of Wall Street" set i lyset af den offentlige debat vedrørende Goldman Sachs opkøb af Dong...

Observations on resistive wall modes

International Nuclear Information System (INIS)

Gerwin, R.A.; Finn, J.M.

1996-01-01

Several results on resistive wall modes and their application to tokamaks are presented. First, it is observed that in the presence of collisional parallel dynamics there is an exact cancellation to lowest order of the dissipative and sound wave effects for an ideal Ohm's law. This is easily traced to the fact that the parallel dynamics occurs along the perturbed magnetic field lines for such electromagnetic modes. Such a cancellation does not occur in the resistive layer of a tearing-like mode. The relevance to models for resistive wall modes using an electrostatic Hammett-Perkins type operator to model Landau damping will be discussed. Second, we observe that with an ideal Ohm's law, resistive wall modes can be destabilized by rotation in that part of parameter space in which the ideal MHD modes are stable with the wall at infinity. This effect can easily be explained by interpreting the resistive wall instability in terms of mode coupling between the backward stable MHD mode and a stable mode locked into the wall. Such an effect can occur for very small rotation for tearing-resistive wall modes in which inertia dominates viscosity in the layer, but the mode is stabilized by further rotation. For modes for which viscosity dominates in the layer, rotation is purely stabilizing. For both tearing models, a somewhat higher rotation frequency gives stability essentially whenever the tearing mode is stable with a perfectly conducting wall. These tearing/resistive wall results axe also simply explained in terms of mode coupling. It has been shown that resonant external ideal modes can be stabilized in the presence of resistive wall and resistive plasma with rotation of order the nominal tearing mode growth rate. We show that these modes behave as resistive wall tearing modes in the sense above. This strengthens the suggestion that rotational stabilization of the external kink with a resistive wall is due to the presence of resistive layers, even for ideal modes

Experience of Electricite de France in the use of sea water for cooling thermal power stations

International Nuclear Information System (INIS)

Boyer, R.M.E.; Malherbe, C.

1979-01-01

The sea is a practically unlimited reserve of water for cooling conventional or nuclear thermal power stations. On the other hand, its use gives rise to numerous problems relating to the design and operation of the equipment. The main problems encountered at EDF are associated with filter screens (clogging, corrosion), the distribution ducts (encrusted organisms), the water boxes, the tube plates, and above all, the condenser tubes (corrosion, corrosion-erosion). The site-construction of several PWR nuclear sets has caused EDF to dispense with the use of cuprous alloys for the tubes of condensers using sea water; these are now of thin-walled seam-welded titanium. In order to reduce further the risks of leakage, these tubes are expanded into double tube plates between which fresh water is trapped under pressure. (author)

Supersymmetric domain walls

NARCIS (Netherlands)

Bergshoeff, Eric A.; Kleinschmidt, Axel; Riccioni, Fabio

2012-01-01

We classify the half-supersymmetric "domain walls," i.e., branes of codimension one, in toroidally compactified IIA/IIB string theory and show to which gauged supergravity theory each of these domain walls belong. We use as input the requirement of supersymmetric Wess-Zumino terms, the properties of

Abdominal wall blocks in adults

DEFF Research Database (Denmark)

Børglum, Jens; Gögenür, Ismail; Bendtsen, Thomas F

2016-01-01

been introduced with success. Future research should also investigate the effect of specific abdominal wall blocks on neuroendocrine and inflammatory stress response after surgery.  Summary USG abdominal wall blocks in adults are commonplace techniques today. Most abdominal wall blocks are assigned......Purpose of review Abdominal wall blocks in adults have evolved much during the last decade; that is, particularly with the introduction of ultrasound-guided (USG) blocks. This review highlights recent advances of block techniques within this field and proposes directions for future research.......  Recent findings Ultrasound guidance is now considered the golden standard for abdominal wall blocks in adults, even though some landmark-based blocks are still being investigated. The efficiency of USG transversus abdominis plane blocks in relation to many surgical procedures involving the abdominal wall...

Sea level change

Digital Repository Service at National Institute of Oceanography (India)

Church, J.A.; Clark, P.U.; Cazenave, A.; Gregory, J.M.; Jevrejeva, S.; Levermann, A.; Merrifield, M.A.; Milne, G.A.; Nerem, R.S.; Nunn, P.D.; Payne, A.J.; Pfeffer, W.T.; Stammer, D.; Unnikrishnan, A.S.

This chapter considers changes in global mean sea level, regional sea level, sea level extremes, and waves. Confidence in projections of global mean sea level rise has increased since the Fourth Assessment Report (AR4) because of the improved...

Air-sea exchange studies at the North Sea

NARCIS (Netherlands)

Leeuw, G. de; Eijk, A.M.J. van; Kunz, G.J.; Veefkind, P.J.

1996-01-01

The North Sea can be considered as a local 'inner' sea in which many processes are quite different from these over the open ocean. The surrounding land has a major influence, being the source for man-made aerosols and gases, whereas the North Sea acts as a sink for these. At the same time the North

Sea ice dynamics across the Mid-Pleistocene transition in the Bering Sea.

Science.gov (United States)

Detlef, H; Belt, S T; Sosdian, S M; Smik, L; Lear, C H; Hall, I R; Cabedo-Sanz, P; Husum, K; Kender, S

2018-03-05

Sea ice and associated feedback mechanisms play an important role for both long- and short-term climate change. Our ability to predict future sea ice extent, however, hinges on a greater understanding of past sea ice dynamics. Here we investigate sea ice changes in the eastern Bering Sea prior to, across, and after the Mid-Pleistocene transition (MPT). The sea ice record, based on the Arctic sea ice biomarker IP 25 and related open water proxies from the International Ocean Discovery Program Site U1343, shows a substantial increase in sea ice extent across the MPT. The occurrence of late-glacial/deglacial sea ice maxima are consistent with sea ice/land ice hysteresis and land-glacier retreat via the temperature-precipitation feedback. We also identify interactions of sea ice with phytoplankton growth and ocean circulation patterns, which have important implications for glacial North Pacific Intermediate Water formation and potentially North Pacific abyssal carbon storage.

Log-layer mismatch and modeling of the fluctuating wall stress in wall-modeled large-eddy simulations

Science.gov (United States)

Yang, Xiang I. A.; Park, George Ilhwan; Moin, Parviz

2017-10-01

Log-layer mismatch refers to a chronic problem found in wall-modeled large-eddy simulation (WMLES) or detached-eddy simulation, where the modeled wall-shear stress deviates from the true one by approximately 15 % . Many efforts have been made to resolve this mismatch. The often-used fixes, which are generally ad hoc, include modifying subgrid-scale stress models, adding a stochastic forcing, and moving the LES-wall-model matching location away from the wall. An analysis motivated by the integral wall-model formalism suggests that log-layer mismatch is resolved by the built-in physics-based temporal filtering. In this work we investigate in detail the effects of local filtering on log-layer mismatch. We show that both local temporal filtering and local wall-parallel filtering resolve log-layer mismatch without moving the LES-wall-model matching location away from the wall. Additionally, we look into the momentum balance in the near-wall region to provide an alternative explanation of how LLM occurs, which does not necessarily rely on the numerical-error argument. While filtering resolves log-layer mismatch, the quality of the wall-shear stress fluctuations predicted by WMLES does not improve with our remedy. The wall-shear stress fluctuations are highly underpredicted due to the implied use of LES filtering. However, good agreement can be found when the WMLES data are compared to the direct numerical simulation data filtered at the corresponding WMLES resolutions.

Late Holocene sea-level rise in Tampa Bay: Integrated reconstruction using biomarkers, pollen, organic-walled dinoflagellate cysts, and diatoms

NARCIS (Netherlands)

Soelen, E.E. van; Lammertsma, E.I.; Cremer, H.; Donders, T.H.; Sangiorgi, F.; Brooks, G.R.; Larson, R.A.; Sinninghe Damsté, J.S.; Wagner-Cremer, F.; Reichart, G.J.

2010-01-01

A suite of organic geochemical, micropaleontological and palynological proxies was applied to sediments from Southwest Florida, to study the Holocene environmental changes associated with sea-level rise. Sediments were recovered from Hillsborough Bay, part of Tampa Bay, and studied using biomarkers,

Desalination of Walls and Façades

Science.gov (United States)

Wedekind, W.; Jáuregui Arreola, K.; Siegesmund, S.

2012-04-01

For large monumental objects like walls and façades, the common technique of applying poultices for desalination often are not effective. This practice is neither cost effective nor does it lead to the desired result of desalination. To manage the conservation and desalination of these kinds of objects, several sprinkling techniques are known and have been applied on historical objects. For example, in the wooden warship Vasa, which was excavated from the sea bottom in Stockholm/Sweden, a sprinkling method was applied in 1961 for conservation and desalination. A sprinkling method to desalinate porous mineral materials will be presented using three different case studies: the rock cut monument no. 825 in Petra/Jordan, the medieval monastary church of the former Franziscan convent in Zeitz/Germany and the baroque monastary church Santa Monica in Guadalajara/Mexico. Before to start with practical conservation, the material- and petropysical properties, focoussed on water transport properties, like porosity, pore size distribution, water uptake and drying rate were investigadet. Diagnostic investigations on the objects included the mapping of deterioration, moister content measurements and salt accumulation determined by borehole cuts samples at depth. In the sprinkling method water is sprayed onto the wall surface through nozzels arranged in a modular grid. Depending on the sprinkling duration, a small or a large amount of water seeps into the porous materials, whereby the depth penetration can be adjusted accordingly. The water not absorbed by the stone runs off the facade and can be collected in liter amounts and tested by electrical conductivity with respect to the dissolved substances. After the drying of the wall's surface and the accumulation of salt at the material's surface, the procedure is repeated. For each subsequent washing a lower content of salt should be brought to the surface. Step by step the salt concentration will eventually decrease to almost

Möbius domain-wall fermions on gradient-flowed dynamical HISQ ensembles

Science.gov (United States)

Berkowitz, Evan; Bouchard, Chris; Chang, Chia Cheng; Clark, M. A.; Joó, Bálint; Kurth, Thorsten; Monahan, Christopher; Nicholson, Amy; Orginos, Kostas; Rinaldi, Enrico; Vranas, Pavlos; Walker-Loud, André

2017-09-01

We report on salient features of a mixed lattice QCD action using valence Möbius domain-wall fermions solved on the dynamical Nf=2 +1 +1 highly improved staggered quark sea-quark ensembles generated by the MILC Collaboration. The approximate chiral symmetry properties of the valence fermions are shown to be significantly improved by utilizing the gradient-flow scheme to first smear the highly improved staggered quark configurations. The greater numerical cost of the Möbius domain-wall inversions is mitigated by the highly efficient QUDA library optimized for NVIDIA GPU accelerated compute nodes. We have created an interface to this optimized QUDA solver in Chroma. We provide tuned parameters of the action and performance of QUDA using ensembles with the lattice spacings a ≃{0.15 ,0.12 ,0.09 } fm and pion masses mπ≃{310 ,220 ,130 } MeV . We have additionally generated two new ensembles with a ˜0.12 fm and mπ˜{400 ,350 } MeV . With a fixed flow time of tg f=1 in lattice units, the residual chiral symmetry breaking of the valence fermions is kept below 10% of the light quark mass on all ensembles, mres≲0.1 ×ml , with moderate values of the fifth dimension L5 and a domain-wall height M5≤1.3 . As a benchmark calculation, we perform a continuum, infinite volume, physical pion and kaon mass extrapolation of FK±/Fπ± and demonstrate our results are independent of flow time and consistent with the FLAG determination of this quantity at the level of less than one standard deviation.

Topological domain walls in helimagnets

Science.gov (United States)

Schoenherr, P.; Müller, J.; Köhler, L.; Rosch, A.; Kanazawa, N.; Tokura, Y.; Garst, M.; Meier, D.

2018-05-01

Domain walls naturally arise whenever a symmetry is spontaneously broken. They interconnect regions with different realizations of the broken symmetry, promoting structure formation from cosmological length scales to the atomic level1,2. In ferroelectric and ferromagnetic materials, domain walls with unique functionalities emerge, holding great promise for nanoelectronics and spintronics applications3-5. These walls are usually of Ising, Bloch or Néel type and separate homogeneously ordered domains. Here we demonstrate that a wide variety of new domain walls occurs in the presence of spatially modulated domain states. Using magnetic force microscopy and micromagnetic simulations, we show three fundamental classes of domain walls to arise in the near-room-temperature helimagnet iron germanium. In contrast to conventional ferroics, the domain walls exhibit a well-defined inner structure, which—analogous to cholesteric liquid crystals—consists of topological disclination and dislocation defects. Similar to the magnetic skyrmions that form in the same material6,7, the domain walls can carry a finite topological charge, permitting an efficient coupling to spin currents and contributions to a topological Hall effect. Our study establishes a new family of magnetic nano-objects with non-trivial topology, opening the door to innovative device concepts based on helimagnetic domain walls.

ACCELERATION OF SEA LEVEL RISE OVER MALAYSIAN SEAS FROM SATELLITE ALTIMETER

Directory of Open Access Journals (Sweden)

A. I. A. Hamid

2016-09-01

Full Text Available Sea level rise becomes our concern nowadays as a result of variously contribution of climate change that cause by the anthropogenic effects. Global sea levels have been rising through the past century and are projected to rise at an accelerated rate throughout the 21st century. Due to this change, sea level is now constantly rising and eventually will threaten many low-lying and unprotected coastal areas in many ways. This paper is proposing a significant effort to quantify the sea level trend over Malaysian seas based on the combination of multi-mission satellite altimeters over a period of 23 years. Eight altimeter missions are used to derive the absolute sea level from Radar Altimeter Database System (RADS. Data verification is then carried out to verify the satellite derived sea level rise data with tidal data. Eight selected tide gauge stations from Peninsular Malaysia, Sabah and Sarawak are chosen for this data verification. The pattern and correlation of both measurements of sea level anomalies (SLA are evaluated over the same period in each area in order to produce comparable results. Afterwards, the time series of the sea level trend is quantified using robust fit regression analysis. The findings clearly show that the absolute sea level trend is rising and varying over the Malaysian seas with the rate of sea level varies and gradually increase from east to west of Malaysia. Highly confident and correlation level of the 23 years measurement data with an astonishing root mean square difference permits the absolute sea level trend of the Malaysian seas has raised at the rate 3.14 ± 0.12 mm yr-1 to 4.81 ± 0.15 mm yr-1 for the chosen sub-areas, with an overall mean of 4.09 ± 0.12 mm yr-1. This study hopefully offers a beneficial sea level information to be applied in a wide range of related environmental and climatology issue such as flood and global warming.

Acceleration of Sea Level Rise Over Malaysian Seas from Satellite Altimeter

Science.gov (United States)

Hamid, A. I. A.; Din, A. H. M.; Khalid, N. F.; Omar, K. M.

2016-09-01

Sea level rise becomes our concern nowadays as a result of variously contribution of climate change that cause by the anthropogenic effects. Global sea levels have been rising through the past century and are projected to rise at an accelerated rate throughout the 21st century. Due to this change, sea level is now constantly rising and eventually will threaten many low-lying and unprotected coastal areas in many ways. This paper is proposing a significant effort to quantify the sea level trend over Malaysian seas based on the combination of multi-mission satellite altimeters over a period of 23 years. Eight altimeter missions are used to derive the absolute sea level from Radar Altimeter Database System (RADS). Data verification is then carried out to verify the satellite derived sea level rise data with tidal data. Eight selected tide gauge stations from Peninsular Malaysia, Sabah and Sarawak are chosen for this data verification. The pattern and correlation of both measurements of sea level anomalies (SLA) are evaluated over the same period in each area in order to produce comparable results. Afterwards, the time series of the sea level trend is quantified using robust fit regression analysis. The findings clearly show that the absolute sea level trend is rising and varying over the Malaysian seas with the rate of sea level varies and gradually increase from east to west of Malaysia. Highly confident and correlation level of the 23 years measurement data with an astonishing root mean square difference permits the absolute sea level trend of the Malaysian seas has raised at the rate 3.14 ± 0.12 mm yr-1 to 4.81 ± 0.15 mm yr-1 for the chosen sub-areas, with an overall mean of 4.09 ± 0.12 mm yr-1. This study hopefully offers a beneficial sea level information to be applied in a wide range of related environmental and climatology issue such as flood and global warming.

Temperature, Salinity, Oxygen, Phosphate, pH and Alkalinity data collected in the North Atlantic Ocean, Baltic Sea, Barents Sea, Greenland Sea, North Sea, Norwegian Sea and White Sea from R/Vs Artemovsk, Atlantida, Okeanograf, Professor Rudovits, and ice observations, 1957 - 1995 (NODC Accession 0073674)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Temperature, Salinity, Oxygen, Phosphate, pH and Alkalinity data collected in the North Atlantic Ocean, Baltic Sea, Barents Sea, Greenland Sea, North Sea, Norwegian...

Prediction of wall shear stresses in transitional boundary layers using near-wall mean velocity profiles

International Nuclear Information System (INIS)

Jeon, Woo Pyung; Shin, Sung Ho; Kang, Shin Hyoung

2000-01-01

The local wall shear stress in transitional boundary layer was estimated from the near-wall mean velocity data using the principle of Computational Preston tube Method(CPM). The previous DNS and experimental databases of transitional boundary layers were used to demonstrate the accuracy of the method and to provide the applicable range of wall unit y + . The skin friction coefficients predicted by the CPM agreed well with those from previous studies. To reexamine the applicability of the CPM, near-wall hot-wire measurements were conducted in developing transitional boundary layers on a flat plate with different freestream turbulence intensities. The intermittency profiles across the transitional boundary layers were reasonably obtained from the conditional sampling technique. An empirical correlation between the representative intermittency near the wall and the free parameter K 1 of the extended wall function of CPM has been newly proposed using the present and other experimental data. The CPM has been verified as a useful tool to measure the wall shear stress in transitional boundary layer with reasonable accuracy

Hot wire production of single-wall and multi-wall carbon nanotubes

Science.gov (United States)

Dillon, Anne C.; Mahan, Archie H.; Alleman, Jeffrey L.

2010-10-26

Apparatus (210) for producing a multi-wall carbon nanotube (213) may comprise a process chamber (216), a furnace (217) operatively associated with the process chamber (216), and at least one filament (218) positioned within the process chamber (216). At least one power supply (220) operatively associated with the at least one filament (218) heats the at least one filament (218) to a process temperature. A gaseous carbon precursor material (214) operatively associated with the process chamber (216) provides carbon for forming the multi-wall carbon nanotube (213). A metal catalyst material (224) operatively associated with the process (216) catalyzes the formation of the multi-wall carbon nanotube (213).

Implementing Green Walls in Schools.

Science.gov (United States)

McCullough, Michael B; Martin, Michael D; Sajady, Mollika A

2018-01-01

Numerous studies in applied pedagogical design have shown that, at all educational levels, direct exposure to the natural environment can enhance learning by improving student attention and behaviors. Implementing green walls-a "vertical garden," or "living wall" interior wall that typically includes greenery, a growing medium (soil or substrate) and a water delivery system-provides environmental health benefits, but also provides a practical application within classrooms for minimizing directed attention fatigue in students by connecting them to "outdoor nature" within the indoor environment. Hands-on "project-based" learning is another pedagogical strategy that has proved to be effective across the spectrum of educational levels and across subject areas. Green walls have the potential to inspire critical thinking through a combination of project-based learning strategies and environmental education. The authors have outlined a curriculum involving the implementation of an indoor living wall system within a classroom-learning environment, incorporating project-based learning modules that interact with the wall. In conjunction with the passive health benefits of a green wall, project-based curriculum models can connect students interactively with indoor nature and have the potential to inspire real-world thinking related to science, technology, engineering, art, and mathematics fields within the indoor learning environment. Through a combination of these passive and interactive modes, students are connected to nature in the indoor environment regardless of weather conditions outdoors. Future research direction could include post-construction studies of the effectiveness of project-based curricula related to living walls, and the long-term impacts of implementing green walls in classrooms on school achievement and student behaviors.

Anisotropy of domain wall resistance

Science.gov (United States)

Viret; Samson; Warin; Marty; Ott; Sondergard; Klein; Fermon

2000-10-30

The resistive effect of domain walls in FePd films with perpendicular anisotropy was studied experimentally as a function of field and temperature. The films were grown directly on MgO substrates, which induces an unusual virgin magnetic configuration composed of 60 nm wide parallel stripe domains. This allowed us to carry out the first measurements of the anisotropy of domain wall resistivity in the two configurations of current perpendicular and parallel to the walls. At 18 K, we find 8.2% and 1.3% for the domain wall magnetoresistance normalized to the wall width (8 nm) in these two respective configurations. These values are consistent with the predictions of Levy and Zhang.

First biological measurements of deep-sea corals from the Red Sea.

Science.gov (United States)

Roder, C; Berumen, M L; Bouwmeester, J; Papathanassiou, E; Al-Suwailem, A; Voolstra, C R

2013-10-03

It is usually assumed that metabolic constraints restrict deep-sea corals to cold-water habitats, with 'deep-sea' and 'cold-water' corals often used as synonymous. Here we report on the first measurements of biological characters of deep-sea corals from the central Red Sea, where they occur at temperatures exceeding 20°C in highly oligotrophic and oxygen-limited waters. Low respiration rates, low calcification rates, and minimized tissue cover indicate that a reduced metabolism is one of the key adaptations to prevailing environmental conditions. We investigated four sites and encountered six species of which at least two appear to be undescribed. One species is previously reported from the Red Sea but occurs in deep cold waters outside the Red Sea raising interesting questions about presumed environmental constraints for other deep-sea corals. Our findings suggest that the present understanding of deep-sea coral persistence and resilience needs to be revisited.

First biological measurements of deep-sea corals from the Red Sea.

KAUST Repository

Roder, Cornelia

2013-10-03

It is usually assumed that metabolic constraints restrict deep-sea corals to cold-water habitats, with \\'deep-sea\\' and \\'cold-water\\' corals often used as synonymous. Here we report on the first measurements of biological characters of deep-sea corals from the central Red Sea, where they occur at temperatures exceeding 20°C in highly oligotrophic and oxygen-limited waters. Low respiration rates, low calcification rates, and minimized tissue cover indicate that a reduced metabolism is one of the key adaptations to prevailing environmental conditions. We investigated four sites and encountered six species of which at least two appear to be undescribed. One species is previously reported from the Red Sea but occurs in deep cold waters outside the Red Sea raising interesting questions about presumed environmental constraints for other deep-sea corals. Our findings suggest that the present understanding of deep-sea coral persistence and resilience needs to be revisited.

Shielding wall for thermonuclear device

International Nuclear Information System (INIS)

Uchida, Takaho.

1989-01-01

This invention concerns shielding walls opposing to plasmas of a thermonuclear device and it is an object thereof to conduct reactor operation with no troubles even if a portion of shielding wall tiles should be damaged. That is, the shielding wall tiles are constituted as a dual layer structure in which the lower base tiles are connected by means of bolts to first walls. Further, the upper surface tiles are bolt-connected to the layer base tiles. In this structure, the plasma thermal loads are directly received by the surface layer tiles and heat is conducted by means of conduction and radiation to the underlying base tiles and the first walls. Even upon occurrence of destruction accidents to the surface layer tiles caused by incident heat or electromagnetic force upon elimination of plasmas, since the underlying base tiles remain as they are, the first walls constituted with stainless steels, etc. are not directly exposed to the plasmas. Accordingly, the integrity of the first walls having cooling channels can be maintained and sputtering intrusion of atoms of high atom number into the plasmas can be prevented. (I.S.)

KETERASINGAN DALAM FILM WALL-E

Directory of Open Access Journals (Sweden)

Rahmadya Putra Nugraha

2017-05-01

Full Text Available Modern society nowadays technological advances at first create efficiency in human life. Further development of the technology thus drown human in a routine and automation of work created. The State is to be one of the causes of man separated from fellow or the outside world and eventually experiencing alienation. The movie as a mass media function to obtain the movie and entertainment can be informative or educative function is contained, even persuasive. The purpose of this research was conducted to find out the alienation in the movie Wall E. The concepts used to analyze the movie Wall E this is communication, movie, and alienation. The concept of alienation of human alienation from covering its own products of human alienation from its activities, the human alienation from nature of his humanity and human alienation from each other. Paradigm used is a critical paradigm with type a descriptive research with qualitative approach. The method used is the analysis of semiotics Roland Barthes to interpretation the scope of social alienation and fellow humans in the movie.This writing research results found that alienation of humans with other humans influenced the development of the technology and how the human it self represented of technology, not from our fellow human beings. Masyarakat modern saat ini kemajuan teknologi pada awalnya membuat efisiensi dalam kehidupan manusia. Perkembangan selanjutnya teknologi justru menenggelamkan manusia dalam suatu rutinitas dan otomatisasi kerja yang diciptakan. Keadaan itulah yang menjadi salah satu penyebab manusia terpisah dari sesama atau dunia luar dan akhirnya mengalami keterasingan. Film sebagai media massa berfungsi untuk memperoleh hiburan dan dalam film dapat terkandung fungsi informatif maupun edukatif, bahkan persuasif. Tujuan Penelitian ini dilakukan untuk mengetahui Keterasingan dalam film Wall E. Konsep-konsep yang digunakan untuk menganalisis film Wall E ini adalah komunikasi, film, dan

Dressed Domain Walls and holography

International Nuclear Information System (INIS)

Grisa, Luca; Pujolas, Oriol

2008-01-01

The cutoff version of the AdS/CFT correspondence states that the Randall Sundrum scenario is dual to a Conformal Field Theory (CFT) coupled to gravity in four dimensions. The gravitational field produced by relativistic Domain Walls can be exactly solved in both sides of the correspondence, and thus provides one further check of it. We show in the two sides that for the most symmetric case, the wall motion does not lead to particle production of the CFT fields. Still, there are nontrivial effects. Due to the trace anomaly, the CFT effectively renormalizes the Domain Wall tension. On the five dimensional side, the wall is a codimension 2 brane localized on the Randall-Sundrum brane, which pulls the wall in a uniform acceleration. This is perceived from the brane as a Domain Wall with a tension slightly larger than its bare value. In both cases, the deviation from General Relativity appears at nonlinear level in the source, and the leading corrections match to the numerical factors.

Phosphorus dynamics in the Black Sea and Baltic Sea

NARCIS (Netherlands)

Dijkstra, N.|info:eu-repo/dai/nl/372617034

2017-01-01

The dynamics of the key nutrient phosphorus (P) in hypoxic and anoxic marine basins are still incompletely understood. This thesis focuses on the cycling of P in two of such basins: the Baltic Sea and the Black Sea. Water column particulates and sediments from the deep basin of the Black Sea were

Association Mapping of Cell Wall Synthesis Regulatory Genes and Cell Wall Quality in Switchgrass

Energy Technology Data Exchange (ETDEWEB)

Bartley, Laura [Univ. of Oklahoma, Norman, OK (United States). Dept. of Microbiology and Plant Biology; Wu, Y. [Oklahoma State Univ., Stillwater, OK (United States); Zhu, L. [Oklahoma State Univ., Stillwater, OK (United States); Brummer, E. C. [Noble Foundation, Ardmore, OK (United States); Saha, M. [Noble Foundation, Ardmore, OK (United States)

2016-05-31

Inefficient conversion of biomass to biofuels is one of the main barriers for biofuel production from such materials. Approximately half of polysaccharides in biomass remain unused by typical biochemical conversion methods. Conversion efficiency is influenced by the composition and structure of cell walls of biomass. Grasses such as wheat, maize, and rice, as well as dedicated perennial bioenergy crops, like switchgrass, make up ~55% of biomass that can be produced in the United States. Grass cell walls have a different composition and patterning compared with dicotyledonous plants, including the well-studied model plant, Arabidopsis. This project identified genetic determinants of cell wall composition in grasses using both naturally occurring genetic variation of switchgrass and gene network reconstruction and functional assays in rice. In addition, the project linked functional data in rice and other species to switchgrass improvement efforts through curation of the most abundant class of regulators in the switchgrass genome. Characterizing natural diversity of switchgrass for variation in cell wall composition and properties, also known as quality, provides an unbiased avenue for identifying biologically viable diversity in switchgrass cell walls. To characterizing natural diversity, this project generated cell wall composition and enzymatic deconstruction data for ~450 genotypes of the Switchgrass Southern Association Collection (SSAC), a diverse collection composed of 36 switchgrass accessions from the southern U.S. distribution of switchgrass. Comparing these data with other measures of cell wall quality for the same samples demonstrated the complementary nature of the diverse characterization platforms now being used for biomass characterization. Association of the composition data with ~3.2K single nucleotide variant markers identified six significant single nucleotide variant markers co-associated with digestibility and another compositional trait. These

Build an Interactive Word Wall

Science.gov (United States)

Jackson, Julie

2018-01-01

Word walls visually display important vocabulary covered during class. Although teachers have often been encouraged to post word walls in their classrooms, little information is available to guide them. This article describes steps science teachers can follow to transform traditional word walls into interactive teaching tools. It also describes a…

Near wall combustion modeling in spark ignition engines. Part A: Flame–wall interaction

International Nuclear Information System (INIS)

Demesoukas, Sokratis; Caillol, Christian; Higelin, Pascal; Boiarciuc, Andrei; Floch, Alain

2015-01-01

Highlights: • A model for flame–wall interaction in addition to flame wrinkling by turbulence is proposed. • Two sparkplug positions and two lengths are used in a test engine for model validation. • Flame–wall interaction decreases the maximum values of cylinder pressure and heat release rates. • The impact of combustion chamber geometry is taken into account by the flame–wall interaction model. - Abstract: Research and design in the field of spark ignition engines seek to achieve high performance while conserving fuel economy and low pollutant emissions. For the evaluation of various engine configurations, numerical simulations are favored, since they are quick and less expensive than experiments. Various zero-dimensional combustion models are currently used. Both flame front reactions and post-flame processes contribute to the heat release rate. The first part of this study focuses on the role of the flame front on the heat release rate, by modeling the interaction of the flame front with the chamber wall. Post-flame reactions are dealt with in Part B of the study. The basic configurations of flame quenching in laminar flames are also applicable in turbulent flames, which is the case in spark ignition engines. A simplified geometric model of the combustion chamber was used to calculate the mean flame surface, the flame volume and the distribution of flame surface as a function of the distance from the wall. The flame–wall interaction took into account the geometry of the combustion chamber and of the flame, aerodynamic turbulence and the in-cylinder pressure and temperature conditions, through a phenomenological attenuation function of the wrinkling factor. A modified global wrinkling factor as a function of the mean surface distance distribution from the wall was calculated. The impact of flame–wall interaction was simulated for four configurations of the sparkplug position and length: centered and lateral position, and standard and projected

Monitoring sea level and sea surface temperature trends from ERS satellites

DEFF Research Database (Denmark)

Andersen, Ole Baltazar; Knudsen, Per; Beckley, B.

2002-01-01

Data from the two ESA satellites ERS-1 and ERS-2 are used in global and regional analysis of sea level and sea surface temperature trends over the last, 7.8 years. T he ERS satellites and in the future the ENVISAT satellite provide unique opportunity for monitoring both changes in sea level and sea...

First wall of thermonuclear device

International Nuclear Information System (INIS)

Kizawa, Makoto; Koizumi, Makoto; Nishihara, Yoshihiro.

1990-01-01

The first wall of a thermonuclear device is constituted with inner wall tiles, e.g. made of graphite and metal substrates for fixing them. However, since the heat expansion coefficient is different between the metal substrates and intermediate metal members, thermal stresses are caused to deteriorate the endurance of the inner wall tiles. In view of the above, low melting metals are disposed at the portion of contact between the inner wall tiles and the metal substrates and, further, a heat pipe structure is incorporated into the metal substrates. Under the thermal load, for example, during operation of the thermonuclear device, the low melting metals at the portion of contact are melted into liquid metals to enhance the state of contact between the inner wall tiles and the metal substrate to reduce the heat resistance and improve the heat conductivity. Even if there is a difference in the heat expansion coefficient between the inner wall tiles and the metal substrates, neither sharing stresses not thermal stresses are caused. Further, since the heat pipe structure is incorporated into the metal substrates, the lateral unevenness of the temperature in the metal substrates can be eliminated. Thus, the durability of the inner wall tiles can be improved. (N.H.)

A film-based wall shear stress sensor for wall-bounded turbulent flows

Science.gov (United States)

Amili, Omid; Soria, Julio

2011-07-01

In wall-bounded turbulent flows, determination of wall shear stress is an important task. The main objective of the present work is to develop a sensor which is capable of measuring surface shear stress over an extended region applicable to wall-bounded turbulent flows. This sensor, as a direct method for measuring wall shear stress, consists of mounting a thin flexible film on the solid surface. The sensor is made of a homogeneous, isotropic, and incompressible material. The geometry and mechanical properties of the film are measured, and particles with the nominal size of 11 μm in diameter are embedded on the film's surface to act as markers. An optical technique is used to measure the film deformation caused by the flow. The film has typically deflection of less than 2% of the material thickness under maximum loading. The sensor sensitivity can be adjusted by changing the thickness of the layer or the shear modulus of the film's material. The paper reports the sensor fabrication, static and dynamic calibration procedure, and its application to a fully developed turbulent channel flow at Reynolds numbers in the range of 90,000-130,000 based on the bulk velocity and channel full height. The results are compared to alternative wall shear stress measurement methods.

Domain wall engineering through exchange bias

International Nuclear Information System (INIS)

Albisetti, E.; Petti, D.

2016-01-01

The control of the structure and position of magnetic domain walls is at the basis of the development of different magnetic devices and architectures. Several nanofabrication techniques have been proposed to geometrically confine and shape domain wall structures; however, a fine tuning of the position and micromagnetic configuration is hardly achieved, especially in continuous films. This work shows that, by controlling the unidirectional anisotropy of a continuous ferromagnetic film through exchange bias, domain walls whose spin arrangement is generally not favored by dipolar and exchange interactions can be created. Micromagnetic simulations reveal that the domain wall width, position and profile can be tuned by establishing an abrupt change in the direction and magnitude of the exchange bias field set in the system. - Highlights: • Micromagnetic simulations study domain walls in exchange biased thin films. • Novel domain wall configurations can be stabilized via exchange bias. • Domain walls nucleate at the boundary of regions with different exchange bias. • Domain wall width and spin profile are controlled by tuning the exchange bias.

Winter sea ice export from the Laptev Sea preconditions the local summer sea ice cover and fast ice decay

Directory of Open Access Journals (Sweden)

P. Itkin

2017-10-01

Full Text Available Ice retreat in the eastern Eurasian Arctic is a consequence of atmospheric and oceanic processes and regional feedback mechanisms acting on the ice cover, both in winter and summer. A correct representation of these processes in numerical models is important, since it will improve predictions of sea ice anomalies along the Northeast Passage and beyond. In this study, we highlight the importance of winter ice dynamics for local summer sea ice anomalies in thickness, volume and extent. By means of airborne sea ice thickness surveys made over pack ice areas in the south-eastern Laptev Sea, we show that years of offshore-directed sea ice transport have a thinning effect on the late-winter sea ice cover. To confirm the preconditioning effect of enhanced offshore advection in late winter on the summer sea ice cover, we perform a sensitivity study using a numerical model. Results verify that the preconditioning effect plays a bigger role for the regional ice extent. Furthermore, they indicate an increase in volume export from the Laptev Sea as a consequence of enhanced offshore advection, which has far-reaching consequences for the entire Arctic sea ice mass balance. Moreover we show that ice dynamics in winter not only preconditions local summer ice extent, but also accelerate fast-ice decay.

Processes driving sea ice variability in the Bering Sea in an eddying ocean/sea ice model: Mean seasonal cycle

Science.gov (United States)

Li, Linghan; McClean, Julie L.; Miller, Arthur J.; Eisenman, Ian; Hendershott, Myrl C.; Papadopoulos, Caroline A.

2014-12-01

The seasonal cycle of sea ice variability in the Bering Sea, together with the thermodynamic and dynamic processes that control it, are examined in a fine resolution (1/10°) global coupled ocean/sea-ice model configured in the Community Earth System Model (CESM) framework. The ocean/sea-ice model consists of the Los Alamos National Laboratory Parallel Ocean Program (POP) and the Los Alamos Sea Ice Model (CICE). The model was forced with time-varying reanalysis atmospheric forcing for the time period 1970-1989. This study focuses on the time period 1980-1989. The simulated seasonal-mean fields of sea ice concentration strongly resemble satellite-derived observations, as quantified by root-mean-square errors and pattern correlation coefficients. The sea ice energy budget reveals that the seasonal thermodynamic ice volume changes are dominated by the surface energy flux between the atmosphere and the ice in the northern region and by heat flux from the ocean to the ice along the southern ice edge, especially on the western side. The sea ice force balance analysis shows that sea ice motion is largely associated with wind stress. The force due to divergence of the internal ice stress tensor is large near the land boundaries in the north, and it is small in the central and southern ice-covered region. During winter, which dominates the annual mean, it is found that the simulated sea ice was mainly formed in the northern Bering Sea, with the maximum ice growth rate occurring along the coast due to cold air from northerly winds and ice motion away from the coast. South of St Lawrence Island, winds drive the model sea ice southwestward from the north to the southwestern part of the ice-covered region. Along the ice edge in the western Bering Sea, model sea ice is melted by warm ocean water, which is carried by the simulated Bering Slope Current flowing to the northwest, resulting in the S-shaped asymmetric ice edge. In spring and fall, similar thermodynamic and dynamic

Sea Surface Height Variability and Eddy Statistical Properties in the Red Sea

KAUST Repository

Zhan, Peng

2013-01-01

Satellite sea surface height (SSH) data over 1992-2012 are analyzed to study the spatial and temporal variability of sea level in the Red Sea. Empirical orthogonal functions (EOF) analysis suggests the remarkable seasonality of SSH in the Red Sea

Hyphal walls of isolated lichen fungi

International Nuclear Information System (INIS)

Galun, M.; Braun, A.; Frensdorff, A.; Galun, E.

1976-01-01

The hyphal walls of three mycobionts, isolated from the lichens Xanthoria parietina, Tornabenia intricata and Sarcogyne sp. were investigated by two techniques: microaudiography of fungal colonies exposed to radioactive carbohydrate precursors; and binding, in vivo, of fluorescein conjugated lectins to hyphal walls of such colonies. N-( 3 H) acetylglucosamine was readily incorporated into tips, young hyphal walls and septa of the three mycobionts and the free-living fungus Trichoderma viride, but not into Phytophthora citrophthora, indicating that chitin is a major component of the mycobionts' hyphal walls. All three mycobionts, but neither of the free-living fungi, incorporated ( 3 H) mannose and ( 3 H) mannitol into their hyphal walls. Fluorescein-conjugated wheat germ agglutinin was bound to the hyphal walls of the three mycobionts and T. viride, but not to the walls of P. citrophthora; the binding pattern was similar to the grain pattern obtained in audiographs after short N-( 3 H) acetylglucosamine labelling. As wheat germ agglutinin binds specifically to chitin oligomers, the lectin binding tests further confirmed that chitin is a mycobiont hyphal wall component. Binding characteristics of several fluorescein-conjugated lectins to the three mycobionts indicated that this technique can yield useful information concerning the chemical composition of hyphal wall surfaces. (orig./AJ) [de

Highly variable Pliocene sea surface conditions in the Norwegian Sea

Directory of Open Access Journals (Sweden)

P. E. Bachem

2017-09-01

Full Text Available The Pliocene was a time of global warmth with small sporadic glaciations, which transitioned towards the larger-scale Pleistocene glacial–interglacial variability. Here, we present high-resolution records of sea surface temperature (SST and ice-rafted debris (IRD in the Norwegian Sea from 5.32 to 3.14 Ma, providing evidence that the Pliocene surface conditions of the Norwegian Sea underwent a series of transitions in response to orbital forcing and gateway changes. Average SSTs are 2 °C above the regional Holocene mean, with notable variability on millennial to orbital timescales. Both gradual changes and threshold effects are proposed for the progression of regional climate towards the Late Pliocene intensification of Northern Hemisphere glaciation. Cooling from 4.5 to 4.3 Ma may be linked to the onset of poleward flow through the Bering Strait. This cooling was further intensified by a period of cool summers due to weak obliquity forcing. A 7 °C warming of the Norwegian Sea at 4.0 Ma suggests a major increase in northward heat transport from the North Atlantic, leading to an enhanced zonal SST gradient in the Nordic Seas, which may be linked to the expansion of sea ice in the Arctic and Nordic Seas. A warm Norwegian Sea and enhanced zonal temperature gradient between 4.0 and 3.6 Ma may have been a priming factor for increased glaciation around the Nordic Seas due to enhanced evaporation and precipitation at high northern latitudes.

Contemporary Arctic Sea Level

Science.gov (United States)

Cazenave, A. A.

2017-12-01

During recent decades, the Arctic region has warmed at a rate about twice the rest of the globe. Sea ice melting is increasing and the Greenland ice sheet is losing mass at an accelerated rate. Arctic warming, decrease in the sea ice cover and fresh water input to the Arctic ocean may eventually impact the Arctic sea level. In this presentation, we review our current knowledge of contemporary Arctic sea level changes. Until the beginning of the 1990s, Arctic sea level variations were essentially deduced from tide gauges located along the Russian and Norwegian coastlines. Since then, high inclination satellite altimetry missions have allowed measuring sea level over a large portion of the Arctic Ocean (up to 80 degree north). Measuring sea level in the Arctic by satellite altimetry is challenging because the presence of sea ice cover limits the full capacity of this technique. However adapted processing of raw altimetric measurements significantly increases the number of valid data, hence the data coverage, from which regional sea level variations can be extracted. Over the altimetry era, positive trend patterns are observed over the Beaufort Gyre and along the east coast of Greenland, while negative trends are reported along the Siberian shelf. On average over the Arctic region covered by satellite altimetry, the rate of sea level rise since 1992 is slightly less than the global mea sea level rate (of about 3 mm per year). On the other hand, the interannual variability is quite significant. Space gravimetry data from the GRACE mission and ocean reanalyses provide information on the mass and steric contributions to sea level, hence on the sea level budget. Budget studies show that regional sea level trends over the Beaufort Gyre and along the eastern coast of Greenland, are essentially due to salinity changes. However, in terms of regional average, the net steric component contributes little to the observed sea level trend. The sea level budget in the Arctic

The Importance of Hydraulic Structures for Society: Quay Walls and Dikes in the Netherlands

Directory of Open Access Journals (Sweden)

de Gijt J.G.

2015-12-01

Full Text Available Since mankind exists, men have undertaken engineering activities to make their life more pleasant and secure. However this has not been an easy task, especially in the past. The knowledge of mathematics and physics to describe engineering problems became available only since 1400-1500. Nevertheless, great achievements have been made by man before that time, e.g. the pyramids in Egypt, the first sluice in China, the Borobudur temple in Indonesia, and the design and building activities of the Inca’s in South America. To illustrate this development, also the world economy, world ecology will be shortly mentioned. The structures that are briefly discussed in this paper are: soil and concrete dams for generating electricity, reservoirs for irrigation and drinking water, dikes, sluices, inland and sea, tunnels, and quay walls. This paper presents an overview of hydraulic structures in general with the emphasis on quay walls and dikes in the Netherlands. Examples of these structures will be discussed illustrating present state of the art and also with a view to the future. Conclusions and recommendations are given to enhance the knowledge of hydraulic structures.

Sea Surface Temperature and Ocean Color Variability in the South China Sea

Science.gov (United States)

Conaty, A. P.

2001-12-01

The South China Sea is a marginal sea in the Southeast Asian region whose surface circulation is driven by monsoons and whose surface currents have complex seasonal patterns. Its rich natural resources and strategic location have made its small islands areas of political dispute among the neighboring nations. This study aims to show the seasonal and interannual variability of sea surface temperature and ocean color in South China Sea. It makes use of NOAA's Advanced Very High Resolution Radiometer (AVHRR) satellite data sets on sea surface temperature for the period 1981-2000 and NASA's Nimbus-7 Coastal Zone Color Scanner (CZCS) and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite data sets on pigment concentration (ocean color) for the period 1981-1996 and 1997-2000, respectively. Transect lines were drawn along several potential hotspot areas to show the variability in sea surface temperature and pigment concentration through time. In-situ data on sea surface temperature along South China Sea were likewise plotted to see the variability with time. Higher seasonal variability in sea surface temperature was seen at higher latitudes. Interannual variability was within 1-3 Kelvin. In most areas, pigment concentration was higher during northern hemisphere winter and autumn, after the monsoon rains, with a maximum of 30 milligrams per cubic meter.

Coastal boundary layers in ocean modelling: an application to the Adriatic Sea

International Nuclear Information System (INIS)

Malanotte Rizzoli, P.; Dell'Orto, F.

1981-01-01

Boundary layers play an important role in modelling geophysical fluid-dynamical flows, in as much as they constitute regions of ageostrophic dynamics in which the physical balances characterizing the main interior of the water mass break down. A short synopsis is given of important boundary layers in ocean circulation modelling with specific emphasis drawn upon side wall boundary layers, namely those adjacent to the coastlines of the considered basin. Application of boundary layer analysis is thereafter made for one specific phenomenological situation, namely the Northern Adriatic Sea and the problem posed by its wintertime seasonal circulation. The analysis furnishes a mathematical model fo the coastal strip adjacent to the Italian shoreline, treated as a boundary layer in the density field, starting from general model equations valid throughout the interior of the Northern Adriatic. The boundary layer model is consequently used to modify the side wall boundary condition for the interior density field. Related numerical experiments are shown and compared with previous standard experiments in which the boundary layer contribution to the density field has not been considered. (author)

fK /f{pi} in Full QCD with Domain Wall Valence Quarks

Energy Technology Data Exchange (ETDEWEB)

Silas Beane; Paulo Bedaque; Konstantinos Orginos; Martin Savage

2007-05-01

We compute the ratio of pseudoscalar decay constants f{sub K}/f{sub {pi}} using domain-wall valence quarks and rooted improved Kogut-Susskind sea quarks. By employing continuum chiral perturbation theory, we extract the Gasser-Leutwyler low-energy constant L{sub 5}, and extrapolate f{sub K}/f{sub {pi}} to the physical point. We find: f{sub K}/f{sub {pi}} = 1.218 {+-} 0.002{sub -0.024}{sup +0.011} where the first error is statistical and the second error is an estimate of the systematic due to chiral extrapolation and fitting procedures. This value agrees within the uncertainties with the determination by the MILC collaboration, calculated using Kogut-Susskind valence quarks, indicating that systematic errors arising from the choice of lattice valence quark are small.

Vulnerability of marginal seas to sea level rise

Science.gov (United States)

Gomis, Damia; Jordà, Gabriel

2017-04-01

Sea level rise (SLR) is a serious thread for coastal areas and has a potential negative impact on society and economy. SLR can lead for instance to land loss, beach reduction, increase of the damage of marine storms on coastal infrastructures and to the salinization of underground water streams. It is well acknowledged that future SLR will be inhomogeneous across the globe, with regional differences of up to 100% with respect to global mean sea level (GMSL). Several studies have addressed the projections of SLR at regional scale, but most of them are based on global climate models (GCMs) that have a relatively coarse spatial resolution (>1°). In marginal seas this has proven to be a strong limitation, as their particular configurations require spatial resolutions that are not reachable by present GCMs. A paradigmatic case is the Mediterranean Sea, connected to the global ocean through the Strait of Gibraltar, a narrow passage of 14 km width. The functioning of the Mediterranean Sea involves a variety of processes including an overturning circulation, small-scale convection and a rich mesoscale field. Moreover, the long-term evolution of Mediterranean sea level has been significantly different from the global mean during the last decades. The observations of present climate and the projections for the next decades have lead some authors to hypothesize that the particular characteristics of the basin could allow Mediterranean mean sea level to evolve differently from the global mean. Assessing this point is essential to undertake proper adaptation strategies for the largely populated Mediterranean coastal areas. In this work we apply a new approach that combines regional and global projections to analyse future SLR. In a first step we focus on the quantification of the expected departures of future Mediterranean sea level from GMSL evolution and on the contribution of different processes to these departures. As a result we find that, in spite of its particularities

Thin walls in regions with vacuum energy

Energy Technology Data Exchange (ETDEWEB)

Garfinkle, D [Florida Univ., Gainesville, FL (USA). Dept. of Physics; Vuille, C [Embry-Riddle Aeronautical Univ., Prescott, AZ (USA). Dept. of Math/Physical Science

1989-12-01

The motion of a thin wall is treated in the case where the regions on either side of the wall have vacuum energy. This treatment generalises previous results involving domain walls in vacuum and also previous results involving the properties of false vacuum bubbles. The equation of state for a domain wall is{tau} = {sigma} where {tau} is the tension in the wall and {sigma} is the energy density. We consider the motion of a more general class of walls having equation of state {tau}{Gamma}{sigma} with 0{le}{Gamma}{le}1. Spherically symmetric and planar symmetric walls are examined. We also find the global structure of the wall spacetime. (author).

Deep-sea Hexactinellida (Porifera) of the Weddell Sea

Science.gov (United States)

Janussen, Dorte; Tabachnick, Konstantin R.; Tendal, Ole S.

2004-07-01

New Hexactinellida from the deep Weddel Sea are described. This moderately diverse hexactinellid fauna includes 14 species belonging to 12 genera, of which five species and one subgenus are new to science: Periphragella antarctica n. sp., Holascus pseudostellatus n. sp., Caulophacus (Caulophacus) discohexactinus n. sp., C. ( Caulodiscus) brandti n. sp., C. ( Oxydiscus) weddelli n. sp., and C. ( Oxydiscus) n. subgen. So far, 20 hexactinellid species have been reported from the deep Weddell Sea, 15 are known from the northern part and 10 only from here, while 10 came from the southern area, and five of these only from there. However, this apparent high "endemism" of Antarctic hexactinellid sponges is most likely the result of severe undersampling of the deep-sea fauna. We find no reason to believe that a division between an oceanic and a more continental group of species exists. The current poor database indicates that a substantial part of the deep hexactinellid fauna of the Weddell Sea is shared with other deep-sea regions, but it does not indicate a special biogeographic relationship with any other ocean.

Action of trypsin on structural changes of collagen fibres from sea cucumber (Stichopus japonicus).

Science.gov (United States)

Liu, Zi-Qiang; Tuo, Feng-Yan; Song, Liang; Liu, Yu-Xin; Dong, Xiu-Ping; Li, Dong-Mei; Zhou, Da-Yong; Shahidi, Fereidoon

2018-08-01

Trypsin, a representative serine proteinase, was used to hydrolyse the collagen fibres from sea cucumber (Stichopus japonicus) to highlight the role of serine proteinase in the autolysis of sea cucumber. Partial disaggregation of collagen fibres into collagen fibrils upon trypsin treatment occurred. The trypsin treatment also caused a time-dependent release of water-soluble glycosaminoglycans and proteins. Therefore, the degradation of the proteoglycan bridges between collagen fibrils might account for the disaggregation of collagen fibrils. For trypsin-treated collagen fibres (72 h), the collagen fibrils still kept their structural integrity and showed characteristic D-banding pattern, and the dissolution rate of hydroxyproline was just 0.21%. Meanwhile, Fourier transform infrared analysis showed the collagen within trypsin-treated collagen fibres (72 h) still retaining their triple-helical conformation. These results suggested that serine proteinase participated in the autolysis of S. japonicus body wall by damaging the proteoglycan bridges between collagen fibrils and disintegrating the latter. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sea Ice Drift Monitoring in the Bohai Sea Based on GF4 Satellite

Science.gov (United States)

Zhao, Y.; Wei, P.; Zhu, H.; Xing, B.

2018-04-01

The Bohai Sea is the inland sea with the highest latitude in China. In winter, the phenomenon of freezing occurs in the Bohai Sea due to frequent cold wave influx. According to historical records, there have been three serious ice packs in the Bohai Sea in the past 50 years which caused heavy losses to our economy. Therefore, it is of great significance to monitor the drift of sea ice and sea ice in the Bohai Sea. The GF4 image has the advantages of short imaging time and high spatial resolution. Based on the GF4 satellite images, the three methods of SIFT (Scale invariant feature - the transform and Scale invariant feature transform), MCC (maximum cross-correlation method) and sift combined with MCC are used to monitor sea ice drift and calculate the speed and direction of sea ice drift, the three calculation results are compared and analyzed by using expert interpretation and historical statistical data to carry out remote sensing monitoring of sea ice drift results. The experimental results show that the experimental results of the three methods are in accordance with expert interpretation and historical statistics. Therefore, the GF4 remote sensing satellite images have the ability to monitor sea ice drift and can be used for drift monitoring of sea ice in the Bohai Sea.

Climatology of sea breezes along the Red Sea coast of Saudi Arabia

KAUST Repository

Khan, Basit; Abualnaja, Yasser; Al-Subhi, Abdullah M.; Nellayaputhenpeedika, Mohammedali; Nellikkattu Thody, Manoj; Sturman, Andrew P.

2018-01-01

and Atmospheric Administration (NOAA) are used to investigate the climatology of sea breezes over the eastern side of the Red Sea region. Results show existence of separate sea breeze systems along different segments of the Red Sea coastline. Based on the physical

Plasma-wall interaction

International Nuclear Information System (INIS)

Reichle, R.

2004-01-01

This document gathers the 43 slides presented in the framework of the week long lecture 'hot plasmas 2004' and dedicated to plasma-wall interaction in a tokamak. This document is divided into 4 parts: 1) thermal load on the wall, power extraction and particle recovery, 2) basic edge plasma physics, 3) processes that drive the plasma-solid interaction, and 4) material conditioning (surface treatment...) for ITER

Reconstitution of a secondary cell wall in a secondary cell wall-deficient Arabidopsis mutant.

Science.gov (United States)

Sakamoto, Shingo; Mitsuda, Nobutaka

2015-02-01

The secondary cell wall constitutes a rigid frame of cells in plant tissues where rigidity is required. Deposition of the secondary cell wall in fiber cells contributes to the production of wood in woody plants. The secondary cell wall is assembled through co-operative activities of many enzymes, and their gene expression is precisely regulated by a pyramidal cascade of transcription factors. Deposition of a transmuted secondary cell wall in empty fiber cells by expressing selected gene(s) in this cascade has not been attempted previously. In this proof-of-concept study, we expressed chimeric activators of 24 transcription factors that are preferentially expressed in the stem, in empty fiber cells of the Arabidopsis nst1-1 nst3-1 double mutant, which lacks a secondary cell wall in fiber cells, under the control of the NST3 promoter. The chimeric activators of MYB46, SND2 and ANAC075, as well as NST3, reconstituted a secondary cell wall with different characteristics from those of the wild type in terms of its composition. The transgenic lines expressing the SND2 or ANAC075 chimeric activator showed increased glucose and xylose, and lower lignin content, whereas the transgenic line expressing the MYB46 chimeric activator showed increased mannose content. The expression profile of downstream genes in each transgenic line was also different from that of the wild type. This study proposed a new screening strategy to identify factors of secondary wall formation and also suggested the potential of the artificially reconstituted secondary cell walls as a novel raw material for production of bioethanol and other chemicals. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

Optimization of multiplane ?PIV for wall shear stress and wall topography characterization

NARCIS (Netherlands)

Rossi, M.; Lindken, R.; Westerweel, J.

2009-01-01

Multiplane ?PIV can be utilized to determine the wall shear stress and wall topology from the measured flow over a structured surface. A theoretical model was developed to predict the measurement error for the surface topography and shear stress, based on a theoretical analysis of the precision in

Seasonal variation of deep-sea bioluminescence in the Ionian Sea

International Nuclear Information System (INIS)

Craig, Jessica; Jamieson, Alan J.; Bagley, Philip M.; Priede, Imants G.

2011-01-01

The ICDeep (Image Intensified Charge Coupled Device for Deep sea research) profiler was used to measure the density of deep bioluminescent animals (BL) through the water column in the east, west and mid-Ionian Sea and in the Algerian Basin. A west to east decrease in BL density was found. Generalized additive modelling was used to investigate seasonal variation in the east and west Ionian Sea (NESTOR and NEMO neutrino telescope sites, respectively) from BL measurements in autumn 2008 and spring 2009. A significant seasonal effect was found in the west Ionian Sea (p<0.001), where a deep autumnal peak in BL density occurred between 500 and 2400 m. No significant seasonal variation in BL density was found in the east Ionian Sea (p=0.07). In both spring and autumn, significant differences in BL density were found through the water column between the east and west Ionian Sea (p<0.001).

Seasonal variation of deep-sea bioluminescence in the Ionian Sea

Energy Technology Data Exchange (ETDEWEB)

Craig, Jessica, E-mail: j.craig@abdn.ac.u [University of Aberdeen, Oceanlab, Main Street, Newburgh, Aberdeenshire, AB41 6AA (United Kingdom); Jamieson, Alan J.; Bagley, Philip M.; Priede, Imants G. [University of Aberdeen, Oceanlab, Main Street, Newburgh, Aberdeenshire, AB41 6AA (United Kingdom)

2011-01-21

The ICDeep (Image Intensified Charge Coupled Device for Deep sea research) profiler was used to measure the density of deep bioluminescent animals (BL) through the water column in the east, west and mid-Ionian Sea and in the Algerian Basin. A west to east decrease in BL density was found. Generalized additive modelling was used to investigate seasonal variation in the east and west Ionian Sea (NESTOR and NEMO neutrino telescope sites, respectively) from BL measurements in autumn 2008 and spring 2009. A significant seasonal effect was found in the west Ionian Sea (p<0.001), where a deep autumnal peak in BL density occurred between 500 and 2400 m. No significant seasonal variation in BL density was found in the east Ionian Sea (p=0.07). In both spring and autumn, significant differences in BL density were found through the water column between the east and west Ionian Sea (p<0.001).

Wall roughness induces asymptotic ultimate turbulence

Science.gov (United States)

Zhu, Xiaojue; Verschoof, Ruben A.; Bakhuis, Dennis; Huisman, Sander G.; Verzicco, Roberto; Sun, Chao; Lohse, Detlef

2018-04-01

Turbulence governs the transport of heat, mass and momentum on multiple scales. In real-world applications, wall-bounded turbulence typically involves surfaces that are rough; however, characterizing and understanding the effects of wall roughness on turbulence remains a challenge. Here, by combining extensive experiments and numerical simulations, we examine the paradigmatic Taylor-Couette system, which describes the closed flow between two independently rotating coaxial cylinders. We show how wall roughness greatly enhances the overall transport properties and the corresponding scaling exponents associated with wall-bounded turbulence. We reveal that if only one of the walls is rough, the bulk velocity is slaved to the rough side, due to the much stronger coupling to that wall by the detaching flow structures. If both walls are rough, the viscosity dependence is eliminated, giving rise to asymptotic ultimate turbulence—the upper limit of transport—the existence of which was predicted more than 50 years ago. In this limit, the scaling laws can be extrapolated to arbitrarily large Reynolds numbers.

Near-wall serpentine cooled turbine airfoil

Science.gov (United States)

Lee, Ching-Pang

2013-09-17

A serpentine coolant flow path (54A-54G) formed by inner walls (50, 52) in a cavity (49) between pressure and suction side walls (22, 24) of a turbine airfoil (20A). A coolant flow (58) enters (56) an end of the airfoil, flows into a span-wise channel (54A), then flows forward (54B) over the inner surface of the pressure side wall, then turns behind the leading edge (26), and flows back along a forward part of the suction side wall, then follows a loop (54E) forward and back around an inner wall (52), then flows along an intermediate part of the suction side wall, then flows into an aft channel (54G) between the pressure and suction side walls, then exits the trailing edge (28). This provides cooling matched to the heating topography of the airfoil, minimizes differential thermal expansion, revives the coolant, and minimizes the flow volume needed.

Thinner regions of intracranial aneurysm wall correlate with regions of higher wall shear stress: a 7.0 tesla MRI

Science.gov (United States)

Blankena, Roos; Kleinloog, Rachel; Verweij, Bon H.; van Ooij, Pim; ten Haken, Bennie; Luijten, Peter R.; Rinkel, Gabriel J.E.; Zwanenburg, Jaco J.M.

2016-01-01

Purpose To develop a method for semi-quantitative wall thickness assessment on in vivo 7.0 tesla (7T) MRI images of intracranial aneurysms for studying the relation between apparent aneurysm wall thickness and wall shear stress. Materials and Methods Wall thickness was analyzed in 11 unruptured aneurysms in 9 patients, who underwent 7T MRI with a TSE based vessel wall sequence (0.8 mm isotropic resolution). A custom analysis program determined the in vivo aneurysm wall intensities, which were normalized to signal of nearby brain tissue and were used as measure for apparent wall thickness (AWT). Spatial wall thickness variation was determined as the interquartile range in AWT (the middle 50% of the AWT range). Wall shear stress was determined using phase contrast MRI (0.5 mm isotropic resolution). We performed visual and statistical comparisons (Pearson’s correlation) to study the relation between wall thickness and wall shear stress. Results 3D colored AWT maps of the aneurysms showed spatial AWT variation, which ranged from 0.07 to 0.53, with a mean variation of 0.22 (a variation of 1.0 roughly means a wall thickness variation of one voxel (0.8mm)). In all aneurysms, AWT was inversely related to WSS (mean correlation coefficient −0.35, P<0.05). Conclusions A method was developed to measure the wall thickness semi-quantitatively, using 7T MRI. An inverse correlation between wall shear stress and AWT was determined. In future studies, this non-invasive method can be used to assess spatial wall thickness variation in relation to pathophysiologic processes such as aneurysm growth and –rupture. PMID:26892986

Deep-sea geohazards in the South China Sea

Science.gov (United States)

Wu, Shiguo; Wang, Dawei; Völker, David

2018-02-01

Various geological processes and features that might inflict hazards identified in the South China Sea by using new technologies and methods. These features include submarine landslides, pockmark fields, shallow free gas, gas hydrates, mud diapirs and earthquake tsunami, which are widely distributed in the continental slope and reefal islands of the South China Sea. Although the study and assessment of geohazards in the South China Sea came into operation only recently, advances in various aspects are evolving at full speed to comply with National Marine Strategy and `the Belt and Road' Policy. The characteristics of geohazards in deep-water seafloor of the South China Sea are summarized based on new scientific advances. This progress is aimed to aid ongoing deep-water drilling activities and decrease geological risks in ocean development.

50 CFR 697.12 - At-sea sea sampler/observer coverage.

Science.gov (United States)

2010-10-01

... sampler/observer access to and use of the vessel's communications equipment and personnel upon request for...) Allow the sea sampler/observer to inspect and copy the vessel's log, communications log, and records... must: (1) Notify the sea sampler/observer of any sea turtles, marine mammals, or other specimens taken...

Development of P4140 video data wall projector; Video data wall projector

Energy Technology Data Exchange (ETDEWEB)

Watanabe, H.; Inoue, H. [Toshiba Corp., Tokyo (Japan)

1998-12-01

The P4140 is a 3 cathode-ray tube (CRT) video data wall projector for super video graphics array (SVGA) signals. It is used as an image display unit, providing a large screen when several sets are put together. A high-quality picture has been realized by higher resolution and improved color uniformity technology. A new convergence adjustment system has also been developed through the optimal combination of digital and analog technologies. This video data wall installation has been greatly enhanced by the automation of cubes and cube performance settings. The P4140 video data wall projector can be used for displaying not only data but video as well. (author)

Deglacial sea level history of the East Siberian Sea and Chukchi Sea margins

Science.gov (United States)

Cronin, Thomas M.; O'Regan, Matt; Pearce, Christof; Gemery, Laura; Toomey, Michael; Semiletov, Igor; Jakobsson, Martin

2017-09-01

Deglacial (12.8-10.7 ka) sea level history on the East Siberian continental shelf and upper continental slope was reconstructed using new geophysical records and sediment cores taken during Leg 2 of the 2014 SWERUS-C3 expedition. The focus of this study is two cores from Herald Canyon, piston core SWERUS-L2-4-PC1 (4-PC1) and multicore SWERUS-L2-4-MC1 (4-MC1), and a gravity core from an East Siberian Sea transect, SWERUS-L2-20-GC1 (20-GC1). Cores 4-PC1 and 20-GC were taken at 120 and 115 m of modern water depth, respectively, only a few meters above the global last glacial maximum (LGM; ˜ 24 kiloannum or ka) minimum sea level of ˜ 125-130 meters below sea level (m b.s.l.). Using calibrated radiocarbon ages mainly on molluscs for chronology and the ecology of benthic foraminifera and ostracode species to estimate paleodepths, the data reveal a dominance of river-proximal species during the early part of the Younger Dryas event (YD, Greenland Stadial GS-1) followed by a rise in river-intermediate species in the late Younger Dryas or the early Holocene (Preboreal) period. A rapid relative sea level rise beginning at roughly 11.4 to 10.8 ka ( ˜ 400 cm of core depth) is indicated by a sharp faunal change and unconformity or condensed zone of sedimentation. Regional sea level at this time was about 108 m b.s.l. at the 4-PC1 site and 102 m b.s.l. at 20-GC1. Regional sea level near the end of the YD was up to 42-47 m lower than predicted by geophysical models corrected for glacio-isostatic adjustment. This discrepancy could be explained by delayed isostatic adjustment caused by a greater volume and/or geographical extent of glacial-age land ice and/or ice shelves in the western Arctic Ocean and adjacent Siberian land areas.

Situation in the sea area between the North Sea and the Baltic Sea. Situationen i havsomraadet mellan Nordsjoen och Oestersjoen

Energy Technology Data Exchange (ETDEWEB)

Dybern, B.I.; Soederstroem, J.; Thorell, L.

1984-01-01

Due to the special topographical and hydrological features the seas surrounding Sweden are very sensitive to both natural changes and changes caused by man. The sea area between the North Sea and the Baltic Sea has come into focus during the last few decades due to problems with pollution and its impact on the ecosystems and to overfishing of some commer- cially important species. In order to elucidate the present situation from the Swedish viewpoint, the National Board of Fisheries, the National Environment Protection Board and the County Council of the County Goeteborg and Bohyslaen arranged a Symposium on the Situation in the Sea Area between the North Sea and the Baltic Sea in Goeteborg, 14-16 March, 1983. This volume contains lectures given at that Symposium. In most cases there are English summaries and English translations of texts to figures and tables.

COMPARISON OF SENSORS FOR RESISTIVE WALL MODE FEEDBACK CONTROL. MILESTONE No.145 ''CONTAINING PLASMA INSTABILITIES WITH METAL WALLS''

International Nuclear Information System (INIS)

STRAIT, E.J.; CHU, M.S.; GAROFALO, A.M.; LAHAYE, R.J.; OKABAYASHI, M.; REIMERDES, H.; SCOVILLE, J.T.; TURNBULL, A.D.

2002-01-01

OAK A271 COMPARISON OF SENSORS FOR RESISTIVE WALL MODE FEEDBACK CONTROL MILESTONE No.145 CONTAINING PLASMA INSTABILITIES WITH METAL WALLS. The most serious instabilities in the tokamak are those described by ideal magneto-hydrodynamic theory. These modes limit the stable operating space of the tokamak. The ideal MHD calculations predict the stable operating space of the tokamak may be approximately doubled when a perfectly conducting metal wall is placed near the plasma boundary, compared to the case with no wall (free boundary). The unstable mode distortions of the plasma column cannot bulge out through a perfectly conducting wall. However, real walls have finite conductivity and when plasmas are operated in the regime between the free boundary stability limit and the perfectly conducting wall limit, the unstable mode encountered in that case the resistive wall mode, can leak out through the metal wall, allowing the mode to keep slowly growing. The slow growth affords the possibility of feedback stabilizing this mode with external coils. DIII-D is making good progress in such feedback stabilization research and in 2002 will use an improved set of mode sensors inside the vacuum vessel and closer to the plasma surface which are expected theoretically to improve the ability to stabilize the resistive wall mode

Diurnal Periodicity in the Supply of Cell Wall Components during Wood Cell Wall Formation

OpenAIRE

細尾, 佳宏

2012-01-01

This review summarizes recent studies on the diurnal periodicity in wood cell wall formation, with a major focus on those that we have conducted. Differences in the innermost surface of developing secondary walls of differentiating conifer tracheids can be seen from day to night Cellulose microfibrils are clearly evident during the day, and amorphous material containing abundant hemicelluloses is prevalent at night. These findings suggest a diurnal periodicity in the supply of cell wall compo...

Mid-infrared pulsed laser ablation of the arterial wall. Mechanical origin of "acoustic" wall damage and its effect on wall healing

NARCIS (Netherlands)

van Erven, L.; van Leeuwen, T. G.; Post, M. J.; van der Veen, M. J.; Velema, E.; Borst, C.

1992-01-01

Pulsed mid-infrared lasers are an alternative to excimer lasers for transluminal angioplasty. The mid-infrared lasers, however, were reported to produce "acoustic" wall damage that might impair the immediate and long-term results. To study the immediate and long-term effects on the arterial wall,

Turbine airfoil with outer wall thickness indicators

Science.gov (United States)

Marra, John J; James, Allister W; Merrill, Gary B

2013-08-06

A turbine airfoil usable in a turbine engine and including a depth indicator for determining outer wall blade thickness. The airfoil may include an outer wall having a plurality of grooves in the outer surface of the outer wall. The grooves may have a depth that represents a desired outer surface and wall thickness of the outer wall. The material forming an outer surface of the outer wall may be removed to be flush with an innermost point in each groove, thereby reducing the wall thickness and increasing efficiency. The plurality of grooves may be positioned in a radially outer region of the airfoil proximate to the tip.

Finite element modeling of single-walled carbon nanotubes with introducing a new wall thickness

International Nuclear Information System (INIS)

Jalalahmadi, B; Naghdabadi, R

2007-01-01

A three-dimensional finite element (FE) model for armchair, zigzag and chiral single-walled carbon nanotubes (SWCNTs) is proposed. By considering the covalent bonds as connecting elements between carbon atoms, a nanotube is simulated as a space frame-like structure. Here, the carbon atoms act as joints of the connecting elements. To create the FE models, nodes are placed at the locations of carbon atoms and the bonds between them are modeled using three-dimensional elastic beam elements. Using Morse atomic potential, the elastic moduli of beam elements are obtained via considering a linkage between molecular and continuum mechanics. Also, a new wall thickness ( bond diameter) equal to 0.1296 nm is introduced. In order to demonstrate the applicability of FE model and new wall thickness, the influence of tube wall thickness, diameter and chirality on the Young's modulus of SWCNTs is investigated. It is found that the choice of wall thickness significantly affects the calculation of Young's modulus. For the values of wall thickness used in the literature, the Young's moduli are estimated which agree very well with the corresponding theoretical results and experimental measurements. We also investigate the dependence of elastic moduli on diameter and chirality of the nanotube. The larger tube diameter, the higher Young's modulus of SWCNT. The Young's modulus of chiral SWCNTs is found to be generally larger than that of armchair and zigzag SWCNTs. The presented results demonstrate that the proposed FE model and wall thickness may provide a valuable tool for studying the mechanical behavior of carbon nanotubes and their application in nano-composites

Fusion: first wall problems

International Nuclear Information System (INIS)

Behrisch, R.

1976-01-01

Some of the relevant elementary atomic processes which are expected to be of significance to the first wall of a fusion reactor are reviewed. Up to the present, most investigations have been performed at relatively high ion energies, typically E greater than 5 keV, and even in this range the available data are very poor. If the plasma wall interaction takes place at energies of E greater than 1 keV the impurity introduction and first wall erosion which will take place predominantly by sputtering, will be large and may severely limit the burning time of the plasma. The wall bombardment and surface erosion will presumably not decrease substantially by introducing a divertor. The erosion can only be kept low if the energy of the bombarding ions and neutrals can be kept below the threshold for sputtering of 1 to 10 eV. 93 refs

Ultrasonography of chest wall lesion

Energy Technology Data Exchange (ETDEWEB)

Park, Cheol Min; Kim, C. H.; Cha, I. H.; Chung, K. B.; Ser, W. H.; Choi, Y. H. [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1989-12-15

Thirty-one patients with chest wall diseases were studied with ultrasound to evaluate its role in chest wall lesions. There were eight infectious conditions, 9 benign tumors, 11 malignant lesions and 3 miscellaneous cases. Diffuse chest wall thickening with heterogeneous echogenicity and obliteration of subcutaneous fat layer are findings of acute infection. In cases of tuberculous smpyema necessitates, pleural abnormality extended to the chest wall through intercostal space. Benign tumors were well demarcated, except in 4 cases of lipoma/lipomatosis. Malignant lesions showed irregular soft tissue masses, bone destruction, pleural effusion and subcutaneous invasion. Multiple enlarged lymph nodes were also shown. Ultrasound can demonstrate te internal structure, extent, depth and associated findings such as pleural effusion, bone destruction and peripheral lung involvement. Ultrasound is not only safe, non-invasive and an effective diagnostic imaging modality for chest wall disease, but can also guide aspiration or biopsy for pathologic diagnosis

Ultrasonography of chest wall lesion

International Nuclear Information System (INIS)

Park, Cheol Min; Kim, C. H.; Cha, I. H.; Chung, K. B.; Ser, W. H.; Choi, Y. H.

1989-01-01

Thirty-one patients with chest wall diseases were studied with ultrasound to evaluate its role in chest wall lesions. There were eight infectious conditions, 9 benign tumors, 11 malignant lesions and 3 miscellaneous cases. Diffuse chest wall thickening with heterogeneous echogenicity and obliteration of subcutaneous fat layer are findings of acute infection. In cases of tuberculous smpyema necessitates, pleural abnormality extended to the chest wall through intercostal space. Benign tumors were well demarcated, except in 4 cases of lipoma/lipomatosis. Malignant lesions showed irregular soft tissue masses, bone destruction, pleural effusion and subcutaneous invasion. Multiple enlarged lymph nodes were also shown. Ultrasound can demonstrate te internal structure, extent, depth and associated findings such as pleural effusion, bone destruction and peripheral lung involvement. Ultrasound is not only safe, non-invasive and an effective diagnostic imaging modality for chest wall disease, but can also guide aspiration or biopsy for pathologic diagnosis

Bioactive compounds, antioxidant potential, and hepatoprotective activity of sea cucumber (Holothuria atra) against thioacetamide intoxication in rats.

Science.gov (United States)

Esmat, Amr Y; Said, Mahmoud M; Soliman, Amel A; El-Masry, Khaled S H; Badiea, Elham Abdel

2013-01-01

The identification of the active phenolic compounds in the mixed extract of sea cucumber (Holothuria atra) body wall by high-performance liquid chromatography and an assessment of its hepatoprotective activity against thioacetamide-induced liver fibrosis in rats. Female Swiss albino rats were divided into four groups: normal controls; oral administration of a sea cucumber mixed extract (14.4 mg/kg of body weight) on days 2, 4, and 6 weekly for 8 consecutive weeks; intoxication with thioacetamide (200 mg/kg of body weight, intraperitoneally) on days 2 and 6 weekly for 8 wk; and oral administration of a sea cucumber extract and then intoxication with thioacetamide 2 h later for 8 wk. High-performance liquid chromatographic analysis of the sea cucumber mixed extract revealed the presence of some phenolic components, such as chlorogenic acid, pyrogallol, rutin, coumaric acid, catechin, and ascorbic acid. In vitro studies have shown that the extract has a high scavenging activity for the nitric oxide radical, a moderate iron-chelating activity, and a weak inhibitory effect of lipid peroxidation. The subchronic oral administration of sea cucumber extract to the rats did not show any toxic side effects but increased hepatic superoxide dismutase and glutathione peroxidase activities. The coadministration of sea cucumber extract and thioacetamide (protection modality) normalized serum direct bilirubin, alanine and aspartate aminotransferases, hepatic malondialdehyde, and hydroxyproline concentrations and antioxidant enzyme activities. In addition, the histologic examination of liver sections from the protection group that were stained with hematoxylin and eosin showed substantial attenuation of the degenerative cellular changes and regressions in liver fibrosis and necrosis induced by the thioacetamide intoxication. Sea cucumber mixed extract contains physiologically active phenolic compounds with antioxidant activity, which afforded a potential hepatoprotective activity

Domain wall networks on solitons

International Nuclear Information System (INIS)

Sutcliffe, Paul

2003-01-01

Domain wall networks on the surface of a soliton are studied in a simple theory. It consists of two complex scalar fields, in 3+1 dimensions, with a global U(1)xZ n symmetry, where n>2. Solutions are computed numerically in which one of the fields forms a Q ball and the other field forms a network of domain walls localized on the surface of the Q ball. Examples are presented in which the domain walls lie along the edges of a spherical polyhedron, forming junctions at its vertices. It is explained why only a small restricted class of polyhedra can arise as domain wall networks

MICROSTRUCTURE OF THE MID-INTESTINE OF CERTAIN CARP FISH (CIPRINIDAE IN THE WESTERN PART OF THE MIDDLE CASPIAN SEA

Directory of Open Access Journals (Sweden)

N. I. Rabazanov

2016-01-01

Full Text Available Aim. The aim of the study was an attempt to expand on the findings about the structure of the anterior part of the mid-intestine of three species of carp fish: Rutelus frisii kutum (Kamenski, Abramis brama orientalis and Ciprinus caprio (Linne in connection with the feeding habits in the changed conditions of the western coast of the Middle Caspian sea. Studies of the digestive tract can extend the idea of the specifics of the mid-intestine structure due to the feeding of fish in certain environmental conditions of habitat.Methods. Investigations of the digestive tract were carried out, guided by the "Methodological manual" by I.V. Verigina.Findings and discussion. It is shown that in the anatomical and histological structure of the middle intestine was affected by the feeding habits of these types of fish; feeding upon small and soft invertebrates leads to a relatively simple structure of the intestinal wall: mucous layer covers a small part of the total thickness of the wall; there are no collagen structures that perform the function of the mechanical frame and capsules around blood vessels.Conclusion. Simplification of the digestive system emphasizes adaptive capacity appearing in periodic fluctuation of sea water level. The absence of food of a bigger size in the diet of fish results in a relatively simple anatomical and histological structure of the mid-intestine wall. None of the species under study has a differentiated stomach; instead its role is taken by an expanded portion of the fore intestine, similar is the microstructure of the middle part of the intestines of all three species.

Sea-ice cover in the Nordic Seas and the sensitivity to Atlantic water temperatures

Science.gov (United States)

Jensen, Mari F.; Nisancioglu, Kerim H.; Spall, Michael A.

2017-04-01

Changes in the sea-ice cover of the Nordic Seas have been proposed to play a key role for the dramatic temperature excursions associated with the Dansgaard-Oeschger events during the last glacial. However, with its proximity to the warm Atlantic water, how a sea-ice cover can persist in the Nordic Seas is not well understood. In this study, we apply an eddy-resolving configuration of the Massachusetts Institute of Technology general circulation model with an idealized topography to study the presence of sea ice in a Nordic Seas-like domain. We assume an infinite amount of warm Atlantic water present in the south by restoring the southern area to constant temperatures. The sea-surface temperatures are restored toward cold, atmospheric temperatures, and as a result, sea ice is present in the interior of the domain. However, the sea-ice cover in the margins of the Nordic Seas, an area with a warm, cyclonic boundary current, is sensitive to the amount of heat entering the domain, i.e., the restoring temperature in the south. When the temperature of the warm, cyclonic boundary current is high, the margins are free of sea ice and heat is released to the atmosphere. We show that with a small reduction in the temperature of the incoming Atlantic water, the Nordic Seas-like domain is fully covered in sea ice. Warm water is still entering the Nordic Seas, however, this happens at depths below a cold, fresh surface layer produced by melted sea ice. Consequently, the heat release to the atmosphere is reduced along with the eddy heat fluxes. Results suggest a threshold value in the amount of heat entering the Nordic Seas before the sea-ice cover disappears in the margins. We study the sensitivity of this threshold to changes in atmospheric temperatures and vertical diffusivity.

Application of flexi-wall in noise barriers renewal

Directory of Open Access Journals (Sweden)

B. Daee

2015-12-01

Full Text Available This paper presents an experimental study on structural performance of an innovative noise barrier consisting of poly-block, light polyurethane foam (LPF and polyurea. This wall system (flexi-wall is intended to be employed as a vertical extension to existing noise barriers (sound walls in an accelerated construction method. To aid in the wall design, several mechanical tests were conducted on LPF specimens and two full-scale walls were then fabricated employing the same LPF material. The full-scale walls were subjected to lateral loading in order to establish their lateral resistance. A cyclic fatigue test was also performed on a full-scale flexi-wall in order to evaluate the performance of the wall under a repetitive loading condition. The results of the experiments indicated the suitability of flexi-wall in accelerated construction and confirmed that the structural performance of the wall system under lateral loading is satisfactory for the sound wall application. The experimental results were discussed and a preliminary design procedure for application of flexi-wall in sound wall applications was also developed.

A unified wall function for compressible turbulence modelling

Science.gov (United States)

Ong, K. C.; Chan, A.

2018-05-01

Turbulence modelling near the wall often requires a high mesh density clustered around the wall and the first cells adjacent to the wall to be placed in the viscous sublayer. As a result, the numerical stability is constrained by the smallest cell size and hence requires high computational overhead. In the present study, a unified wall function is developed which is valid for viscous sublayer, buffer sublayer and inertial sublayer, as well as including effects of compressibility, heat transfer and pressure gradient. The resulting wall function applies to compressible turbulence modelling for both isothermal and adiabatic wall boundary conditions with the non-zero pressure gradient. Two simple wall function algorithms are implemented for practical computation of isothermal and adiabatic wall boundary conditions. The numerical results show that the wall function evaluates the wall shear stress and turbulent quantities of wall adjacent cells at wide range of non-dimensional wall distance and alleviate the number and size of cells required.

Engineering the Oryza sativa cell wall with rice NAC transcription factors regulating secondary wall formation

Directory of Open Access Journals (Sweden)

Kouki eYoshida

2013-10-01

Full Text Available Plant tissues that require structural rigidity synthesize a thick, strong secondary cell wall of lignin, cellulose and hemicelluloses in a complicated bridged structure. Master regulators of secondary wall synthesis were identified in dicots, and orthologs of these regulators have been identified in monocots, but regulation of secondary cell wall formation in monocots has not been extensively studied. Here we demonstrate that the rice transcription factors SECONDARY WALL NAC DOMAIN PROTEINs (SWNs can regulate secondary wall formation in rice (Oryza sativa and are potentially useful for engineering the monocot cell wall. The OsSWN1 promoter is highly active in sclerenchymatous cells of the leaf blade and less active in xylem cells. By contrast, the OsSWN2 promoter is highly active in xylem cells and less active in sclerenchymatous cells. OsSWN2 splicing variants encode two proteins; the shorter protein (OsSWN2S has very low transcriptional activation ability, but the longer protein (OsSWN2L and OsSWN1 have strong transcriptional activation ability. In rice, expression of an OsSWN2S chimeric repressor, driven by the OsSWN2 promoter, resulted in stunted growth and para-wilting (leaf rolling and browning under normal water conditions due to impaired vascular vessels. The same OsSWN2S chimeric repressor, driven by the OsSWN1 promoter, caused a reduction of cell wall thickening in sclerenchymatous cells, a drooping leaf phenotype, reduced lignin and xylose contents and increased digestibility as forage. These data suggest that OsSWNs regulate secondary wall formation in rice and manipulation of OsSWNs may enable improvements in monocotyledonous crops for forage or biofuel applications.

Hydrodynamics of ultra-relativistic bubble walls

Energy Technology Data Exchange (ETDEWEB)

Leitao, Leonardo, E-mail: lleitao@mdp.edu.ar; Mégevand, Ariel, E-mail: megevand@mdp.edu.ar

2016-04-15

In cosmological first-order phase transitions, gravitational waves are generated by the collisions of bubble walls and by the bulk motions caused in the fluid. A sizeable signal may result from fast-moving walls. In this work we study the hydrodynamics associated to the fastest propagation modes, namely, ultra-relativistic detonations and runaway solutions. We compute the energy injected by the phase transition into the fluid and the energy which accumulates in the bubble walls. We provide analytic approximations and fits as functions of the net force acting on the wall, which can be readily evaluated for specific models. We also study the back-reaction of hydrodynamics on the wall motion, and we discuss the extrapolation of the friction force away from the ultra-relativistic limit. We use these results to estimate the gravitational wave signal from detonations and runaway walls.

Analysis of Apoptosis in Ultraviolet-Induced Sea Cucumber (Stichopus japonicus) Melting Using Terminal Deoxynucleotidyl-Transferase-Mediated dUTP Nick End-Labeling Assay and Cleaved Caspase-3 Immunohistochemistry.

Science.gov (United States)

Yang, Jing-Feng; Gao, Rong-Chun; Wu, Hai-Tao; Li, Peng-Fei; Hu, Xian-Shu; Zhou, Da-Yong; Zhu, Bei-Wei; Su, Yi-Cheng

2015-11-04

The sea cucumber body wall melting phenomenon occurs under certain circumstances, and the mechanism of this phenomenon remains unclear. This study investigated the apoptosis in the ultraviolet (UV)-induced sea cucumber melting phenomenon. Fresh sea cucumbers (Stichopus japonicus) were exposed to UV radiation for half an hour at an intensity of 0.056 mW/cm(2) and then held at room temperature for melting development. The samples were histologically processed into formalin-fixed paraffin-embedded tissues. The apoptosis of samples was analyzed with the terminal deoxynucleotidyl-transferase-mediated dUTP nick end-labeling (TUNEL) assay and cleaved caspase-3 immunohistochemistry. The emergence of TUNEL-positive cells speeds up between 0.5 and 2 h after UV irradiation. Cleaved caspase-3 positive cells were obviously detected in sample tissues immediately after the UV irradiation. These results demonstrated that sea cucumber melting induced by UV irradiation was triggered by the activation of caspase-3 followed by DNA fragmentation in sea cucumber tissue, which was attributed to apoptosis but was not a consequence of autolysis activity.

Variability and Trends in Sea Ice Extent and Ice Production in the Ross Sea

Science.gov (United States)

Comiso, Josefino; Kwok, Ronald; Martin, Seelye; Gordon, Arnold L.

2011-01-01

Salt release during sea ice formation in the Ross Sea coastal regions is regarded as a primary forcing for the regional generation of Antarctic Bottom Water. Passive microwave data from November 1978 through 2008 are used to examine the detailed seasonal and interannual characteristics of the sea ice cover of the Ross Sea and the adjacent Bellingshausen and Amundsen seas. For this period the sea ice extent in the Ross Sea shows the greatest increase of all the Antarctic seas. Variability in the ice cover in these regions is linked to changes in the Southern Annular Mode and secondarily to the Antarctic Circumpolar Wave. Over the Ross Sea shelf, analysis of sea ice drift data from 1992 to 2008 yields a positive rate of increase in the net ice export of about 30,000 sq km/yr. For a characteristic ice thickness of 0.6 m, this yields a volume transport of about 20 cu km/yr, which is almost identical, within error bars, to our estimate of the trend in ice production. The increase in brine rejection in the Ross Shelf Polynya associated with the estimated increase with the ice production, however, is not consistent with the reported Ross Sea salinity decrease. The locally generated sea ice enhancement of Ross Sea salinity may be offset by an increase of relatively low salinity of the water advected into the region from the Amundsen Sea, a consequence of increased precipitation and regional glacial ice melt.

Molecular regulation of plant cell wall extensibility

Science.gov (United States)

Cosgrove, D. J.

1998-01-01

Gravity responses in plants often involve spatial and temporal changes in cell growth, which is regulated primarily by controlling the ability of the cell wall to extend. The wall is thought to be a cellulose-hemicellulose network embedded in a hydrated matrix of complex polysaccharides and a small amount of structural protein. The wall extends by a form of polymer creep, which is mediated by expansins, a novel group of wall-loosening proteins. Expansins were discovered during a molecular dissection of the "acid growth" behavior of cell walls. Expansin alters the rheology of plant walls in profound ways, yet its molecular mechanism of action is still uncertain. It lacks detectable hydrolytic activity against the major components of the wall, but it is able to disrupt noncovalent adhesion between wall polysaccharides. The discovery of a second family of expansins (beta-expansins) sheds light on the biological role of a major group of pollen allergens and implies that expansins have evolved for diverse developmental functions. Finally, the contribution of other processes to wall extensibility is briefly summarized.

Temporal and spatial variations of oceanic pCO2 and air-sea CO2 flux in th Greenland Sea and the Barents Sea

International Nuclear Information System (INIS)

Nakaoka, Shin-Ichiro; Aoki, Shuji; Nakazawa, Takakiyo; Yoshikawa-Inoue, Hisayuki

2006-01-01

In order to elucidate the seasonal and inter annual variations of oceanic CO 2 uptake in the Greenland Sea and the Barents Sea, the partial pressure of CO 2 in the surface ocean (pCO 2 sea ) was measured in all seasons between 1992 and 2001. We derived monthly varying relationships between pCO 2 sea and sea surface temperature (SST) and combined them with the SST data from the NCEP/NCAR reanalysis to determine pCO 2 sea and air-sea CO 2 flux in these seas. The pCO 2 sea values were normalized to the year 1995 by assuming that pCO 2 sea increased at the same growth rate (1.5 μatm/yr) of the pCO 2 in the air (pCO 2 air ) between 1992 and 2001. In 1995, the annual net air-sea CO 2 fluxes were evaluated to be 52 ± 20 gC/m 2 /yr in the Greenland Sea and 46 ± 18 gC/m 2 /yr in the Barents Sea. The CO 2 flux into the ocean reached its maximum in winter and minimum in summer. The wind speed and (delta)pCO 2 (=pCO 2 air -pCO 2 sea ) exerted a greater influence on the seasonal variation than the sea ice coverage. The annual CO 2 uptake examined in this study (70-80 deg N, 20 deg W-40 deg E) was estimated to be 0.050 ± 0.020 GtC/yr in 1995. The inter annual variation in the annual CO 2 uptake was found to be positively correlated with the North Atlantic Oscillation Index (NAOI) via wind strength but negatively correlated with (delta)pCO 2 and the sea ice coverage. The present results indicate that the variability in wind speed and sea ice coverage play a major role, while that in (delta)pCO 2 plays a minor role, in determining the interannual variation of CO 2 uptake in this area

A Review of Double-Walled and Triple-Walled Carbon Nanotube Synthesis and Applications

Directory of Open Access Journals (Sweden)

Kazunori Fujisawa

2016-04-01

Full Text Available Double- and triple-walled carbon nanotubes (DWNTs and TWNTs consist of coaxially-nested two and three single-walled carbon nanotubes (SWNTs. They act as the geometrical bridge between SWNTs and multi-walled carbon nanotubes (MWNTs, providing an ideal model for studying the coupling interactions between different shells in MWNTs. Within this context, this article comprehensively reviews various synthetic routes of DWNTs’ and TWNTs’ production, such as arc discharge, catalytic chemical vapor deposition and thermal annealing of pea pods (i.e., SWNTs encapsulating fullerenes. Their structural features, as well as promising applications and future perspectives are also discussed.

First biological measurements of deep-sea corals from the Red Sea

OpenAIRE

C. Roder; M. L. Berumen; J. Bouwmeester; E. Papathanassiou; A. Al-Suwailem; C. R. Voolstra

2013-01-01

It is usually assumed that metabolic constraints restrict deep-sea corals to cold-water habitats, with ?deep-sea? and ?cold-water? corals often used as synonymous. Here we report on the first measurements of biological characters of deep-sea corals from the central Red Sea, where they occur at temperatures exceeding 20?C in highly oligotrophic and oxygen-limited waters. Low respiration rates, low calcification rates, and minimized tissue cover indicate that a reduced metabolism is one of the ...

Sea Urchin Embryogenesis as Bioindicators of Marine Pollution in Impact Areas of the Sea of Japan/East Sea and the Sea of Okhotsk.

Science.gov (United States)

Lukyanova, Olga N; Zhuravel, Elena V; Chulchekov, Denis N; Mazur, Andrey A

2017-08-01

The embryogenesis of the sea urchin sand dollar Scaphechinus mirabilis was used as bioindicators of seawater quality from the impact areas of the Sea of Japan/East Sea (Peter the Great Bay) and the Sea of Okhotsk (northwestern shelf of Sakhalin Island and western shelf of Kamchatka Peninsula). Fertilization membrane formation, first cleavage, blastula formation, gastrulation, and 2-armed and 4-armed pluteus formation have been analyzed and a number of abnormalities were calculated. Number of embryogenesis anomalies in sand dollar larvae exposed to sea water from different stations in Peter the Great Bay corresponds to pollution level at each area. The Sea of Okhotsk is the main fishing area for Russia. Anthropogenic impact on the marine ecosystem is caused by fishing and transport vessels mainly. But two shelf areas are considered as "hot spots" due to oil and gas drilling. Offshore oil exploitation on the northeastern Sakhalin Island has been started and at present time oil is being drill on oil-extracting platforms continuously. Significant reserves of hydrocarbons are prospected on western Kamchatka shelf, and exploitation drilling in this area was intensified in 2014. A higher number of abnormalities at gastrula and pluteus stages (19-36%) were detected for the stations around oil platforms near Sakhalin Island. On the western Kamchatka shelf number of abnormalities was 7-21%. Such anomalies as exogastrula, incomplete development of pairs of arms were not observed at all; only the delay of development was registered. Eggs, embryos, and larvae of sea urchins are the suitable bioindicators of early disturbances caused by marine pollution in impact ecosystems.

Sea ice algal biomass and physiology in the Amundsen Sea, Antarctica

Directory of Open Access Journals (Sweden)

Kevin R. Arrigo

2014-07-01

Full Text Available Abstract Sea ice covers approximately 5% of the ocean surface and is one of the most extensive ecosystems on the planet. The microbial communities that live in sea ice represent an important food source for numerous organisms at a time of year when phytoplankton in the water column are scarce. Here we describe the distributions and physiology of sea ice microalgae in the poorly studied Amundsen Sea sector of the Southern Ocean. Microalgal biomass was relatively high in sea ice in the Amundsen Sea, due primarily to well developed surface communities that would have been replenished with nutrients during seawater flooding of the surface as a result of heavy snow accumulation. Elevated biomass was also occasionally observed in slush, interior, and bottom ice microhabitats throughout the region. Sea ice microalgal photophysiology appeared to be controlled by the availability of both light and nutrients. Surface communities used an active xanthophyll cycle and effective pigment sunscreens to protect themselves from harmful ultraviolet and visible radiation. Acclimation to low light microhabitats in sea ice was facilitated by enhanced pigment content per cell, greater photosynthetic accessory pigments, and increased photosynthetic efficiency. Photoacclimation was especially effective in the bottom ice community, where ready access to nutrients would have allowed ice microalgae to synthesize a more efficient photosynthetic apparatus. Surprisingly, the pigment-detected prymnesiophyte Phaeocystis antarctica was an important component of surface communities (slush and surface ponds where its acclimation to high light may precondition it to seed phytoplankton blooms after the sea ice melts in spring.

The practicality of defensive ice walls: How would the great ice wall in Game of Thrones hold up?

Science.gov (United States)

Truffer, M.

2017-12-01

The Game of Thrones great ice wall is a colossal feature stretching several hundred miles and over 200 m high. Its purpose is to defend the realm from the wildlings. It is generally pictured as a near vertical wall. An ice wall of these proportions poses interesting challenges, mainly because ice acts as a non-linear shear-thinning fluid. A 200 m high vertical wall would create a large effective stress near its base of almost 1.8 MPa. Typical stresses responsible for ice flow in glaciers and ice sheets are more than a magnitude lower (0.1 MPa). Extrapolating a commonly used flow law for temperate ice to such high stresses would lead to strain rates at the bottom of the wall in excess of 1/day, meaning the wall would rapidly collapse and spread laterally under its own weight. To keep the wall stable, it would help to cool it significantly, as the flow of ice is also very temperature dependent. Cooling to a chilly -40 C would reduce strain rates by two orders of magnitude, but this still leads to significant slumping of the wall within just a few weeks. A time-dependent similarity solution for simplified ice flow equations that describe the evolving shape of the ice wall was provided by Halfar (1981), and demonstrates the rapid decay of the wall. A simple estimate can be derived by assuming that ice is a perfectly plastic fluid, able to maintain a basal shear stress of about 0.1 MPa. A stable ice wall would then spread laterally to about 4 km width. The resulting slope would only be steep at the very margin and the ice wall would loose much of its defensive capabilities. I conclude that the ice wall as proposed would not be a practicable defense under typical Earth conditions, and special magical powers would be necessary to maintain its shape, even for just a few days.

The cell wall of Fusarium oxysporum

NARCIS (Netherlands)

Schoffelmeer, EAM; Klis, FM; Sietsma, JH; Cornelissen, BJC

1999-01-01

Sugar analysis of isolated cell walls from three formae speciales of Fusarium oxysporum showed that they contained not only glucose and (N-acetyl)-glucosamine, but also mannose, galactose, and uronic acids, presumably originating from cell wall glycoproteins. Cell wall glycoproteins accounted for

Characterization of the Sclerotinia sclerotiorum cell wall proteome.

Science.gov (United States)

Liu, Longzhou; Free, Stephen J

2016-08-01

We used a proteomic analysis to identify cell wall proteins released from Sclerotinia sclerotiorum hyphal and sclerotial cell walls via a trifluoromethanesulfonic acid (TFMS) digestion. Cell walls from hyphae grown in Vogel's glucose medium (a synthetic medium lacking plant materials), from hyphae grown in potato dextrose broth and from sclerotia produced on potato dextrose agar were used in the analysis. Under the conditions used, TFMS digests the glycosidic linkages in the cell walls to release intact cell wall proteins. The analysis identified 24 glycosylphosphatidylinositol (GPI)-anchored cell wall proteins and 30 non-GPI-anchored cell wall proteins. We found that the cell walls contained an array of cell wall biosynthetic enzymes similar to those found in the cell walls of other fungi. When comparing the proteins in hyphal cell walls grown in potato dextrose broth with those in hyphal cell walls grown in the absence of plant material, it was found that a core group of cell wall biosynthetic proteins and some proteins associated with pathogenicity (secreted cellulases, pectin lyases, glucosidases and proteases) were expressed in both types of hyphae. The hyphae grown in potato dextrose broth contained a number of additional proteins (laccases, oxalate decarboxylase, peroxidase, polysaccharide deacetylase and several proteins unique to Sclerotinia and Botrytis) that might facilitate growth on a plant host. A comparison of the proteins in the sclerotial cell wall with the proteins in the hyphal cell wall demonstrated that sclerotia formation is not marked by a major shift in the composition of cell wall protein. We found that the S. sclerotiorum cell walls contained 11 cell wall proteins that were encoded only in Sclerotinia and Botrytis genomes. © 2015 The Authors. Molecular Plant Pathology published by British Society for Plant Pathology and John Wiley & Sons Ltd.

Qualitative and Quantitative Saponin Contents in Five Sea Cucumbers from the Indian Ocean

Directory of Open Access Journals (Sweden)

Patrick Flammang

2010-01-01

Full Text Available To avoid predation, holothuroids produce feeding-deterrent molecules in their body wall and viscera, the so-called saponins. Five tropical sea cucumber species of the family Holothuriidae were investigated in order to study their saponin content in two different organs, the body wall and the Cuvierian tubules. Mass spectrometry techniques (MALDI- and ESI-MS were used to detect and analyze saponins. The smallest number of saponins was observed in Holothuria atra, which contained a total of four congeners, followed by Holothuria leucospilota, Pearsonothuria graeffei and Actinopyga echinites with six, eight and ten congeners, respectively. Bohadschia subrubra revealed the highest saponin diversity (19 congeners. Saponin mixtures also varied between the two body compartments within a given animal. A semi-quantitative approach completed these results and showed that a high diversity of saponins is not particularly correlated to a high saponin concentration. Although the complexity of the saponin mixtures described makes the elucidation of their respective biological roles difficult, the comparisons between species and between body compartments give some clues about how these molecules may act as predator repellents.

Qualitative and Quantitative Saponin Contents in Five Sea Cucumbers from the Indian Ocean

Science.gov (United States)

Van Dyck, Séverine; Gerbaux, Pascal; Flammang, Patrick

2010-01-01

To avoid predation, holothuroids produce feeding-deterrent molecules in their body wall and viscera, the so-called saponins. Five tropical sea cucumber species of the family Holothuriidae were investigated in order to study their saponin content in two different organs, the body wall and the Cuvierian tubules. Mass spectrometry techniques (MALDI- and ESI-MS) were used to detect and analyze saponins. The smallest number of saponins was observed in Holothuria atra, which contained a total of four congeners, followed by Holothuria leucospilota, Pearsonothuria graeffei and Actinopyga echinites with six, eight and ten congeners, respectively. Bohadschia subrubra revealed the highest saponin diversity (19 congeners). Saponin mixtures also varied between the two body compartments within a given animal. A semi-quantitative approach completed these results and showed that a high diversity of saponins is not particularly correlated to a high saponin concentration. Although the complexity of the saponin mixtures described makes the elucidation of their respective biological roles difficult, the comparisons between species and between body compartments give some clues about how these molecules may act as predator repellents. PMID:20161976

Hydrodynamics of ultra-relativistic bubble walls

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Leonardo Leitao

2016-04-01

Full Text Available In cosmological first-order phase transitions, gravitational waves are generated by the collisions of bubble walls and by the bulk motions caused in the fluid. A sizeable signal may result from fast-moving walls. In this work we study the hydrodynamics associated to the fastest propagation modes, namely, ultra-relativistic detonations and runaway solutions. We compute the energy injected by the phase transition into the fluid and the energy which accumulates in the bubble walls. We provide analytic approximations and fits as functions of the net force acting on the wall, which can be readily evaluated for specific models. We also study the back-reaction of hydrodynamics on the wall motion, and we discuss the extrapolation of the friction force away from the ultra-relativistic limit. We use these results to estimate the gravitational wave signal from detonations and runaway walls.

Nonsingular walls in plane cholesteric layers

International Nuclear Information System (INIS)

Belyakov, V A; Osipov, M A; Stewart, I W

2006-01-01

The structure of a straight interface (wall) between regions with differing values of the pitch in planar cholesteric layers with finite strength of the surface anchoring is investigated theoretically. It is found that the shape and strength of the anchoring potential influences essentially the structure of the wall and a motionless wall between thermodynamically stable regions without a singularity in the director distribution in the layer can exist for sufficiently weak anchoring only. More specifically, for the existence of such a wall the dimensionless parameter S d = K 22 /Wd (where W is the depth of the anchoring potential, K 22 is the elastic twist modulus and d is the layer thickness) should exceed its critical value, which is dependent on the shape of the anchoring potential. General equations describing the director distribution in the wall are presented. Detailed analysis of these equations is carried out for the case of infinitely strong anchoring at one surface and finite anchoring strength at the second layer surface. It is shown that the wall width L is directly dependent upon the shape and strength of the anchoring potential and that its estimate ranges from d to (dL p ) 1/2 (where L p = K 22 /W is the penetration length), corresponding to different anchoring strengths and shape potentials. The dependence of the director distribution in the wall upon all three Frank elastic moduli is analytically found for some specific limiting cases of the model anchoring potentials. Motion of the wall is briefly investigated and the corresponding calculations performed under the assumption that the shape of a moving wall is the same as a motionless one. It is noted that experimental investigation of the walls in planar cholesteric layers can be used for the determination of the actual shape of surface anchoring potentials

Walrus areas of use in the Chukchi Sea during sparse sea ice cover

Science.gov (United States)

Jay, Chadwick V.; Fischbach, Anthony S.; Kochnev, Anatoly A.

2012-01-01

The Pacific walrus Odobenus rosmarus divergens feeds on benthic invertebrates on the continental shelf of the Chukchi and Bering Seas and rests on sea ice between foraging trips. With climate warming, ice-free periods in the Chukchi Sea have increased and are projected to increase further in frequency and duration. We radio-tracked walruses to estimate areas of walrus foraging and occupancy in the Chukchi Sea from June to November of 2008 to 2011, years when sea ice was sparse over the continental shelf in comparison to historical records. The earlier and more extensive sea ice retreat in June to September, and delayed freeze-up of sea ice in October to November, created conditions for walruses to arrive earlier and stay later in the Chukchi Sea than in the past. The lack of sea ice over the continental shelf from September to October caused walruses to forage in nearshore areas instead of offshore areas as in the past. Walruses did not frequent the deep waters of the Arctic Basin when sea ice retreated off the shelf. Walruses foraged in most areas they occupied, and areas of concentrated foraging generally corresponded to regions of high benthic biomass, such as in the northeastern (Hanna Shoal) and southwestern Chukchi Sea. A notable exception was the occurrence of concentrated foraging in a nearshore area of northwestern Alaska that is apparently depauperate in walrus prey. With increasing sea ice loss, it is likely that walruses will increase their use of coastal haul-outs and nearshore foraging areas, with consequences to the population that are yet to be understood.

SEA and planning

DEFF Research Database (Denmark)

Stoeglehner, G.; Brown, A.L.; Kørnøv, Lone

2009-01-01

, and the relationship of the SEA to the planning activity itself. This paper focuses on the influence that planners have in these implementation processes, postulating the hypothesis that these are key players in achieving effectiveness in SEA. Based upon implementation theory and empirical experience, the paper......As the field of strategic environmental assessment (SEA) has matured, the focus has moved from the development of legislation, guidelines and methodologies towards improving the effectiveness of SEA. Measuring and of course achieving effectiveness is both complex and challenging. This paper...

Immersion Refractometry of Isolated Bacterial Cell Walls

Science.gov (United States)

Marquis, Robert E.

1973-01-01

Immersion-refractometric and light-scattering measurements were adapted to determinations of average refractive indices and physical compactness of isolated bacterial cell walls. The structures were immersed in solutions containing various concentrations of polymer molecules that cannot penetrate into wall pores, and then an estimate was made of the polymer concentration or the refractive index of the polymer solution in which light scattering was reduced to zero. Because each wall preparation was heterogeneous, the refractive index of the medium for zero light scattering had to be estimated by extrapolation. Refractive indices for walls suspended in bovine serum albumin solutions ranged from 1.348 for walls of the rod form of Arthrobacter crystallopoietes to 1.382 for walls of the teichoic acid deficient, 52A5 strain of Staphylococcus aureus. These indices were used to calculate approximate values for solids content per milliliter, and the calculated values agreed closely with those estimated from a knowledge of dextran-impermeable volumes per gram, dry weight, of the walls. When large molecules such as dextrans or serum albumin were used for immersion refractometry, the refractive indices obtained were for entire walls, including both wall polymers and wall water. When smaller molecules that can penetrate wall pores to various extents were used with Micrococcus lysodeikticus walls, the average, apparent refractive index of the structures increased as the molecular size of probing molecules was decreased. It was possible to obtain an estimate of 1.45 to 1.46 for the refractive index of wall polymers, predominantly peptidoglycans in this case, by extrapolating the curve for refractive index versus molecular radius to a value of 0.2 nm, the approximate radius of a water molecule. This relatively low value for polymer refractive index was interpreted as evidence in favor of the amorphous, elastic model of peptidoglycan structure and against the crystalline, rigid

Wall motion abnormality of myocardial infarction

International Nuclear Information System (INIS)

Hayashi, Senji; Tsuda, Takashi; Ojima, Kenji

1984-01-01

By use of the gated blood pool scan, we divided the left ventricular LAO 45 image into 8 sections with the center of the volume as the basal point, and devised a method of quantitative evaluation of the regional wall motion from 2 aspects: 1) wall movement and 2) phase abnormality. To evaluate the wall movement, we obtained the following indeces from count curves of each section: 1) EF1=(end-diastolic count-end-systolic count)/ end-diastolic count, 2) EF2=(maximum count-minimum count)/maximum count, and 3) the difference of the two (EF2-EF1). As indeces of the phase abnormality, the mean value of phases of the pixels (phase characteristics) and the standard deviation (variation) of each section were calculated. Furthermore, the phase delay of each section was calculated as the difference from the earliest phase value of the 8 sections. Control values and standard deviation were obtained from 8 healthy controls. By this method, we analyzed 20 patients with old myocardial infarction. And following results were obtained: 1. Applying this method, we could evaluate the regional wall motion of the left ventricle more precisely, and we considered it would be useful clinically. 2. The abnormal regional wall motion of old myocardial infarction were classified into 4 typical forms as follows: 1) the wall movement decreased extremely. 2) the wall movement decreased, but no phase delay recognized. 3) the wall movement did not decrease, but phase delay was recognized. 4) the wall movement decreased, and phase delay was recognized. (author)

The Role of Auxin in Cell Wall Expansion.

Science.gov (United States)

Majda, Mateusz; Robert, Stéphanie

2018-03-22

Plant cells are surrounded by cell walls, which are dynamic structures displaying a strictly regulated balance between rigidity and flexibility. Walls are fairly rigid to provide support and protection, but also extensible, to allow cell growth, which is triggered by a high intracellular turgor pressure. Wall properties regulate the differential growth of the cell, resulting in a diversity of cell sizes and shapes. The plant hormone auxin is well known to stimulate cell elongation via increasing wall extensibility. Auxin participates in the regulation of cell wall properties by inducing wall loosening. Here, we review what is known on cell wall property regulation by auxin. We focus particularly on the auxin role during cell expansion linked directly to cell wall modifications. We also analyze downstream targets of transcriptional auxin signaling, which are related to the cell wall and could be linked to acid growth and the action of wall-loosening proteins. All together, this update elucidates the connection between hormonal signaling and cell wall synthesis and deposition.

2003 Plant Cell Walls Gordon Conference

Energy Technology Data Exchange (ETDEWEB)

Daniel J. Cosgrove

2004-09-21

This conference will address recent progress in many aspects of cell wall biology. Molecular, genetic, and genomic approaches are yielding major advances in our understanding of the composition, synthesis, and architecture of plant cell walls and their dynamics during growth, and are identifying the genes that encode the machinery needed to make their biogenesis possible. This meeting will bring together international scientists from academia, industry and government labs to share the latest breakthroughs and perspectives on polysaccharide biosynthesis, wood formation, wall modification, expansion and interaction with other organisms, and genomic & evolutionary analyses of wall-related genes, as well as to discuss recent ''nanotechnological'' advances that take wall analysis to the level of a single cell.

Wall Finishes; Carpentry: 901895.

Science.gov (United States)

Dade County Public Schools, Miami, FL.

The course outline is designed to provide instruction in selecting, preparing, and installing wall finishing materials. Prerequisites for the course include mastery of building construction plans, foundations and walls, and basic mathematics. Intended for use in grades 11 and 12, the course contains five blocks of study totaling 135 hours of…

Deglacial sea level history of the East Siberian Sea and Chukchi Sea margins

Science.gov (United States)

Cronin, Thomas M.; O'Regan, Matt; Pearce, Christof; Gemery, Laura; Toomey, Michael; Semiletov, Igor

2017-01-01

Deglacial (12.8–10.7 ka) sea level history on the East Siberian continental shelf and upper continental slope was reconstructed using new geophysical records and sediment cores taken during Leg 2 of the 2014 SWERUS-C3 expedition. The focus of this study is two cores from Herald Canyon, piston core SWERUS-L2-4-PC1 (4-PC1) and multicore SWERUS-L2-4-MC1 (4-MC1), and a gravity core from an East Siberian Sea transect, SWERUS-L2-20-GC1 (20-GC1). Cores 4-PC1 and 20-GC were taken at 120 and 115 m of modern water depth, respectively, only a few meters above the global last glacial maximum (LGM;  ∼  24 kiloannum or ka) minimum sea level of  ∼  125–130 meters below sea level (m b.s.l.). Using calibrated radiocarbon ages mainly on molluscs for chronology and the ecology of benthic foraminifera and ostracode species to estimate paleodepths, the data reveal a dominance of river-proximal species during the early part of the Younger Dryas event (YD, Greenland Stadial GS-1) followed by a rise in river-intermediate species in the late Younger Dryas or the early Holocene (Preboreal) period. A rapid relative sea level rise beginning at roughly 11.4 to 10.8 ka ( ∼  400 cm of core depth) is indicated by a sharp faunal change and unconformity or condensed zone of sedimentation. Regional sea level at this time was about 108 m b.s.l. at the 4-PC1 site and 102 m b.s.l. at 20-GC1. Regional sea level near the end of the YD was up to 42–47 m lower than predicted by geophysical models corrected for glacio-isostatic adjustment. This discrepancy could be explained by delayed isostatic adjustment caused by a greater volume and/or geographical extent of glacial-age land ice and/or ice shelves in the western Arctic Ocean and adjacent Siberian land areas.

Deglacial sea level history of the East Siberian Sea and Chukchi Sea margins

Directory of Open Access Journals (Sweden)

T. M. Cronin

2017-09-01

Full Text Available Deglacial (12.8–10.7 ka sea level history on the East Siberian continental shelf and upper continental slope was reconstructed using new geophysical records and sediment cores taken during Leg 2 of the 2014 SWERUS-C3 expedition. The focus of this study is two cores from Herald Canyon, piston core SWERUS-L2-4-PC1 (4-PC1 and multicore SWERUS-L2-4-MC1 (4-MC1, and a gravity core from an East Siberian Sea transect, SWERUS-L2-20-GC1 (20-GC1. Cores 4-PC1 and 20-GC were taken at 120 and 115 m of modern water depth, respectively, only a few meters above the global last glacial maximum (LGM;  ∼  24 kiloannum or ka minimum sea level of  ∼  125–130 meters below sea level (m b.s.l.. Using calibrated radiocarbon ages mainly on molluscs for chronology and the ecology of benthic foraminifera and ostracode species to estimate paleodepths, the data reveal a dominance of river-proximal species during the early part of the Younger Dryas event (YD, Greenland Stadial GS-1 followed by a rise in river-intermediate species in the late Younger Dryas or the early Holocene (Preboreal period. A rapid relative sea level rise beginning at roughly 11.4 to 10.8 ka ( ∼  400 cm of core depth is indicated by a sharp faunal change and unconformity or condensed zone of sedimentation. Regional sea level at this time was about 108 m b.s.l. at the 4-PC1 site and 102 m b.s.l. at 20-GC1. Regional sea level near the end of the YD was up to 42–47 m lower than predicted by geophysical models corrected for glacio-isostatic adjustment. This discrepancy could be explained by delayed isostatic adjustment caused by a greater volume and/or geographical extent of glacial-age land ice and/or ice shelves in the western Arctic Ocean and adjacent Siberian land areas.

Sensitivity of modeled atmospheric nitrogen species and nitrogen deposition to variations in sea salt emissions in the North Sea and Baltic Sea regions

Directory of Open Access Journals (Sweden)

D. Neumann

2016-03-01

Full Text Available Coarse sea salt particles are emitted ubiquitously from the ocean surface by wave-breaking and bubble-bursting processes. These particles impact the atmospheric chemistry by affecting the condensation of gas-phase species and, thus, indirectly the nucleation of new fine particles, particularly in regions with significant air pollution. In this study, atmospheric particle concentrations are modeled for the North Sea and Baltic Sea regions in northwestern Europe using the Community Multiscale Air Quality (CMAQ modeling system and are compared to European Monitoring and Evaluation Programme (EMEP measurement data. The sea salt emission module is extended by a salinity-dependent scaling of the sea salt emissions because the salinity in large parts of the Baltic Sea is very low, which leads to considerably lower sea salt mass emissions compared to other oceanic regions. The resulting improvement in predicted sea salt concentrations is assessed. The contribution of surf zone emissions is considered separately. Additionally, the impacts of sea salt particles on atmospheric nitrate and ammonium concentrations and on nitrogen deposition are evaluated. The comparisons with observational data show that sea salt concentrations are commonly overestimated at coastal stations and partly underestimated farther inland. The introduced salinity scaling improves the predicted Baltic Sea sea salt concentrations considerably. The dates of measured peak concentrations are appropriately reproduced by the model. The impact of surf zone emissions is negligible in both seas. Nevertheless, they might be relevant because surf zone emissions were cut at an upper threshold in this study. Deactivating sea salt leads to minor increases in NH3 +  NH4+ and HNO3 +  NO3− and a decrease in NO3− concentrations. However, the overall effect on NH3 +  NH4+ and HNO3 +  NO3− concentrations is smaller than the deviation from the measurements. Nitrogen wet deposition is

The Ross Sea Dipole - temperature, snow accumulation and sea ice variability in the Ross Sea region, Antarctica, over the past 2700 years

Science.gov (United States)

Bertler, Nancy A. N.; Conway, Howard; Dahl-Jensen, Dorthe; Emanuelsson, Daniel B.; Winstrup, Mai; Vallelonga, Paul T.; Lee, James E.; Brook, Ed J.; Severinghaus, Jeffrey P.; Fudge, Taylor J.; Keller, Elizabeth D.; Baisden, W. Troy; Hindmarsh, Richard C. A.; Neff, Peter D.; Blunier, Thomas; Edwards, Ross; Mayewski, Paul A.; Kipfstuhl, Sepp; Buizert, Christo; Canessa, Silvia; Dadic, Ruzica; Kjær, Helle A.; Kurbatov, Andrei; Zhang, Dongqi; Waddington, Edwin D.; Baccolo, Giovanni; Beers, Thomas; Brightley, Hannah J.; Carter, Lionel; Clemens-Sewall, David; Ciobanu, Viorela G.; Delmonte, Barbara; Eling, Lukas; Ellis, Aja; Ganesh, Shruthi; Golledge, Nicholas R.; Haines, Skylar; Handley, Michael; Hawley, Robert L.; Hogan, Chad M.; Johnson, Katelyn M.; Korotkikh, Elena; Lowry, Daniel P.; Mandeno, Darcy; McKay, Robert M.; Menking, James A.; Naish, Timothy R.; Noerling, Caroline; Ollive, Agathe; Orsi, Anaïs; Proemse, Bernadette C.; Pyne, Alexander R.; Pyne, Rebecca L.; Renwick, James; Scherer, Reed P.; Semper, Stefanie; Simonsen, Marius; Sneed, Sharon B.; Steig, Eric J.; Tuohy, Andrea; Ulayottil Venugopal, Abhijith; Valero-Delgado, Fernando; Venkatesh, Janani; Wang, Feitang; Wang, Shimeng; Winski, Dominic A.; Winton, V. Holly L.; Whiteford, Arran; Xiao, Cunde; Yang, Jiao; Zhang, Xin

2018-02-01

High-resolution, well-dated climate archives provide an opportunity to investigate the dynamic interactions of climate patterns relevant for future projections. Here, we present data from a new, annually dated ice core record from the eastern Ross Sea, named the Roosevelt Island Climate Evolution (RICE) ice core. Comparison of this record with climate reanalysis data for the 1979-2012 interval shows that RICE reliably captures temperature and snow precipitation variability in the region. Trends over the past 2700 years in RICE are shown to be distinct from those in West Antarctica and the western Ross Sea captured by other ice cores. For most of this interval, the eastern Ross Sea was warming (or showing isotopic enrichment for other reasons), with increased snow accumulation and perhaps decreased sea ice concentration. However, West Antarctica cooled and the western Ross Sea showed no significant isotope temperature trend. This pattern here is referred to as the Ross Sea Dipole. Notably, during the Little Ice Age, West Antarctica and the western Ross Sea experienced colder than average temperatures, while the eastern Ross Sea underwent a period of warming or increased isotopic enrichment. From the 17th century onwards, this dipole relationship changed. All three regions show current warming, with snow accumulation declining in West Antarctica and the eastern Ross Sea but increasing in the western Ross Sea. We interpret this pattern as reflecting an increase in sea ice in the eastern Ross Sea with perhaps the establishment of a modern Roosevelt Island polynya as a local moisture source for RICE.

To detect anomalies in diaphragm walls

NARCIS (Netherlands)

Spruit, R.

2015-01-01

Diaphragm walls are potentially ideal retaining walls for deep excavations in densely built-up areas, as they cause no vibrations during their construction and provide structural elements with high strength and stiffness. In the recent past, however, several projects using diaphragm walls as soil

Authigenic gypsum in a deep sea core from Southeastern Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Guptha, M.V.S.

Authigenic gypsum has been encountered in a deep sea core RC9-157 from the southeastern Arabian Sea at a depth of 4111 m which is a zone of lysocline. The formation of gypsum in the deep sea region is attributed to the prevailing sulphate rich...

Regeneration of near-wall turbulence structures

Science.gov (United States)

Hamilton, James M.; Kim, John J.; Waleffe, Fabian A.

1993-01-01

An examination of the regeneration mechanisms of near-wall turbulence and an attempt to investigate the critical Reynolds number conjecture of Waleffe & Kim is presented. The basis is an extension of the 'minimal channel' approach of Jimenez and Moin which emphasizes the near-wall region and further reduces the complexity of the turbulent flow. Reduction of the flow Reynolds number to the minimum value which will allow turbulence to be sustained has the effect of reducing the ratio of the largest scales to the smallest scales or, equivalently, of causing the near-wall region to fill more of the area between the channel walls. In addition, since each wall may have an active near-wall region, half of the channel is always somewhat redundant. If a plane Couette flow is instead chosen as the base flow, this redundancy is eliminated: the mean shear of a plane Couette flow has a single sign, and at low Reynolds numbers, the two wall regions share a single set of structures. A minimal flow with these modifications possesses, by construction, the strongest constraints which allow sustained turbulence, producing a greatly simplified flow in which the regeneration process can be examined.

Investigations of Antibacterial Activity of Methanol and Aqueous Ex-tracts of the Body Wall of Sea Cucumber Holothuria leucospilota on some Human Pathogenic Bacteria

Directory of Open Access Journals (Sweden)

M. Nazemi

2016-04-01

Full Text Available Introduction & Objective: Holothuria leucospilota, sea cucumber, is a species of the Phylum Echinodermata. Sea cucumbers have the most natural products with biological activity. In this study we investigated the antibacterial activity of aqueous and methanol extract of H. leucospilota used against gram positive and gram negative human pathogenic bacteria. Materials & Methods: 9 Samples of H. leucospilota were harvested from the Hengam Island,. The methanol extract was prepared from the powder of sea cucumber. The antibacterial activity of the extracts was determined by broth dilution methods against clinical Gram-negative bacteria to identify MIC and MBC. Results: Aqueous extract of H. leucospilota was inactive on the bacteria. Methanol extract was active on Gram-negetive bacteria; E. coli, Salmonella typhi and Serratia marcescens. But it killed only Salmonella typhi and Serratia marcescens. The MBC of H. leucospilota methanol extract was 10 mg/ml. Methanol extract was active on all Gram-positive bacteria; B. pumilus, B. cereus and S. aureus but it killed only S. aureus. The MBC of H. leucospilota methanol extract was 40 mg/ml. Conclusion: Based on our results, H. leucospilota methanol extract. can be considered as a source of novel antibiotic. Contrary to many marine organisms, sea cucumbers are active against gram-negative bacteria. (Sci J Hamadan Univ Med Sci 2016; 23 (1:75-82

Revealing Holobiont Structure and Function of Three Red Sea Deep-Sea Corals

KAUST Repository

Yum, Lauren

2014-12-01

Deep-sea corals have long been regarded as cold-water coral; however a reevaluation of their habitat limitations has been suggested after the discovery of deep-sea coral in the Red Sea where temperatures exceed 20˚C. To gain further insight into the biology of deep-sea corals at these temperatures, the work in this PhD employed a holotranscriptomic approach, looking at coral animal host and bacterial symbiont gene expression in Dendrophyllia sp., Eguchipsammia fistula, and Rhizotrochus sp. sampled from the deep Red Sea. Bacterial community composition was analyzed via amplicon-based 16S surveys and cultured bacterial strains were subjected to bioprospecting in order to gauge the pharmaceutical potential of coralassociated microbes. Coral host transcriptome data suggest that coral can employ mitochondrial hypometabolism, anaerobic glycolysis, and surface cilia to enhance mass transport rates to manage the low oxygen and highly oligotrophic Red Sea waters. In the microbial community associated with these corals, ribokinases and retron-type reverse transcriptases are abundantly expressed. In its first application to deep-sea coral associated microbial communities, 16S-based next-generation sequencing found that a single operational taxonomic unit can comprise the majority of sequence reads and that a large number of low abundance populations are present, which cannot be visualized with first generation sequencing. Bioactivity testing of selected bacterial isolates was surveyed over 100 cytological parameters with high content screening, covering several major organelles and key proteins involved in a variety of signaling cascades. Some of these cytological profiles were similar to those of several reference pharmacologically active compounds, which suggest that the bacteria isolates produce compounds with similar mechanisms of action as the reference compounds. The sum of this work offers several mechanisms by which Red Sea deep-sea corals cope with environmental

Sea level hazards: Altimetric monitoring of tsunamis and sea level rise

Science.gov (United States)

Hamlington, Benjamin Dillon

Whether on the short timescale of an impending tsunami or the much longer timescale of climate change-driven sea level rise, the threat stemming from rising and inundating ocean waters is a great concern to coastal populations. Timely and accurate observations of potentially dangerous changes in sea level are vital in determining the precautionary steps that need to be taken in order to protect coastal communities. While instruments from the past have provided in situ measurements of sea level at specific locations across the globe, satellites can be used to provide improved spatial and temporal sampling of the ocean in addition to producing more accurate measurements. Since 1993, satellite altimetry has provided accurate measurements of sea surface height (SSH) with near-global coverage. Not only have these measurements led to the first definitive estimates of global mean sea level rise, satellite altimetry observations have also been used to detect tsunami waves in the open ocean where wave amplitudes are relatively small, a vital step in providing early warning to those potentially affected by the impending tsunami. The use of satellite altimetry to monitor two specific sea level hazards is examined in this thesis. The first section will focus on the detection of tsunamis in the open ocean for the purpose of providing early warning to coastal inhabitants. The second section will focus on estimating secular trends using satellite altimetry data with the hope of improving our understanding of future sea level change. Results presented here will show the utility of satellite altimetry for sea level monitoring and will lay the foundation for further advancement in the detection of the two sea level hazards considered.

Sea-level and deep-sea-temperature variability over the past 5.3 million years.

Science.gov (United States)

Rohling, E J; Foster, G L; Grant, K M; Marino, G; Roberts, A P; Tamisiea, M E; Williams, F

2014-04-24

Ice volume (and hence sea level) and deep-sea temperature are key measures of global climate change. Sea level has been documented using several independent methods over the past 0.5 million years (Myr). Older periods, however, lack such independent validation; all existing records are related to deep-sea oxygen isotope (δ(18)O) data that are influenced by processes unrelated to sea level. For deep-sea temperature, only one continuous high-resolution (Mg/Ca-based) record exists, with related sea-level estimates, spanning the past 1.5 Myr. Here we present a novel sea-level reconstruction, with associated estimates of deep-sea temperature, which independently validates the previous 0-1.5 Myr reconstruction and extends it back to 5.3 Myr ago. We find that deep-sea temperature and sea level generally decreased through time, but distinctly out of synchrony, which is remarkable given the importance of ice-albedo feedbacks on the radiative forcing of climate. In particular, we observe a large temporal offset during the onset of Plio-Pleistocene ice ages, between a marked cooling step at 2.73 Myr ago and the first major glaciation at 2.15 Myr ago. Last, we tentatively infer that ice sheets may have grown largest during glacials with more modest reductions in deep-sea temperature.

Dancing-drawing fields of presence in SeaUnSea

DEFF Research Database (Denmark)

Ramsgaard Thomsen, Mette

2008-01-01

Dance and architecture have much in common as both are concerned with practices of space. For a dancer, the act of choreography occurs through the unfolding of spaces by means of gesture and embodied movement, whereas for an architect, space is the medium through which form emerges and habitation...... is constructed. For both, the first space of experience is the space of the body. This essay is a writing out of the interstices of these two disciplines as they touch and inform each other in the process and production of SeaUnSea, an interactive dance installation which premiered at Siobhan Davies Studios...... as part of Dance Umbrella in London, October 2006. SeaUnSea is a collaboration between the authors, choreographer Carol Brown and architect Mette Ramsgard Thomsen, working with programmer Chiron Mottram....

Indicators and SEA

DEFF Research Database (Denmark)

Gao, Jingjing; Kørnøv, Lone; Christensen, Per

Abstract: Indicators are widely used in SEA to measure, communicate and monitor impacts from a proposed policy, plan or programme, and can improve the effectiveness for the SEA by simplifying the complexity of both assessment and presentation. Indicators can be seen as part of the implementation...... and if the information requirement for different target groups is not addressed. Indicators are widely used in SEA to measure, communicate and monitor impacts from a proposed policy, plan or programme, and can improve the effectiveness for the SEA by simplifying the complexity of both assessment and presentation...... process helping to understand, communicate and, integrate important environmental issues in planning and decision-making. On the other hand, use of indicators can also limit SEA effectiveness, if the ones chosen are biased or limited, if the aggregation gives incorrect interpretation...

Reduced Wall Acetylation Proteins Play Vital and Distinct Roles in Cell Wall O-Acetylation in Arabidopsis

DEFF Research Database (Denmark)

Manabe, Yuzuki; Verhertbruggen, Yves; Gille, Sascha

2013-01-01

The Reduced Wall Acetylation (RWA) proteins are involved in cell wall acetylation in plants. Previously, we described a single mutant, rwa2, which has about 20% lower level of O-acetylation in leaf cell walls and no obvious growth or developmental phenotype. In this study, we generated double....... The quadruple rwa mutant can be completely complemented with the RWA2 protein expressed under 35S promoter, indicating the functional redundancy of the RWA proteins. Nevertheless, the degree of acetylation of xylan, (gluco) mannan, and xyloglucan as well as overall cell wall acetylation is affected differently...... in different combinations of triple mutants, suggesting their diversity in substrate preference. The overall degree of wall acetylation in the rwa quadruple mutant was reduced by 63% compared with the wild type, and histochemical analysis of the rwa quadruple mutant stem indicates defects in cell...

Gas Enrichment at Liquid-Wall Interfaces

NARCIS (Netherlands)

Dammer, S.M.; Lohse, Detlef

2006-01-01

Molecular dynamics simulations of Lennard-Jones systems are performed to study the effects of dissolved gas on liquid-wall and liquid-gas interfaces. Gas enrichment at walls, which for hydrophobic walls can exceed more than 2 orders of magnitude when compared to the gas density in the bulk liquid,

Statistical analysis of silo wall pressures

DEFF Research Database (Denmark)

Ditlevsen, Ove Dalager; Berntsen, Kasper Nikolaj

1998-01-01

Previously published silo wall pressure measurements during plug flow of barley in alarge concrete silo are re-analysed under the hypothesis that the wall pressures are gamma-distributed.The fits of the gamma distribution type to the local pressure data from each measuring cell are satisfactory.......However, the estimated parameters of the gamma distributions turn out to be significantly inhomogeneous overthe silo wall surface. This inhomogeneity is attributed to the geometrical imperfections of the silo wall.Motivated by the engineering importance of the problem a mathematical model for constructing astochastic...... gamma-type continuous pressure field is given. The model obeys the necessary equilibrium conditionsof the wall pressure field and reflects the spatial correlation properties as estimated from simultaneouslymeasured pressures at different locations along a horizontal perimeter....

Studies on first wall and plasma wall interaction in JT-60

International Nuclear Information System (INIS)

Nakamura, Hiroo

1988-12-01

This paper describes studies on first wall and plasma wall interaction in JT-60. Main results are as follows; (1) To select JT-60 first wall material, various RandD were done in FY1975 ∼ 1976. Mo was selected as first wall materials of limiters and divertor plates because of its reliability under a high heat flux condition. (2) Development of low-Z material has been done to reduce impurity problem of Mo first wall. As a result, titanium carbide (TiC) was selected as a coating material on the Mo. High heat load testing has been done for TiC coated Mo limiter same as JT-60. This material can survive under the condition of 1 kW/cm 2 x 10 s, expected in JT-60 limiter design. (3) To reduce high heat load on the divertor plate, separatrix swing is proposed. Optimum frequency of the sweeping is evaluated to be 2 Hz in JT-60. For a discharge with heating power of 30 MW and duration time of 10 s, in addition to the separatrix swing, remote radiative cooling in the divertor region is necessary. Moreover, calculations of erosion thickness have been done for stainless steel, Mo, graphite, TiC and silicon caibide under high heat flux during plasma disruption. (4) In divertor experiments in JT-60, divertor functions on particle, heat load and impurity controls have been demonstrated. In elctron density of 6 x 10 19 m -3 , particle fueling rate of 20 MW NB heating (3 Pa m 3 /s) can be exhausted by divertor pumping system. Effectiveness of remote radiative cooling is demonstrated under the condition of 20 MW NB heating power. Also, separatrix swing is demonstrated to reduce heat load on the divertor plate. Total radiation in main plasma is 5 ∼ 10% of total absorbed power. (author) 120 refs

Dynamics of strings between walls

International Nuclear Information System (INIS)

Eto, Minoru; Fujimori, Toshiaki; Nagashima, Takayuki; Nitta, Muneto; Ohashi, Keisuke; Sakai, Norisuke

2009-01-01

Configurations of vortex strings stretched between or ending on domain walls were previously found to be 1/4 Bogomol'nyi-Prasad-Sommerfield (BPS) states in N=2 supersymmetric gauge theories in 3+1 dimensions. Among zero modes of string positions, the center of mass of strings in each region between two adjacent domain walls is shown to be non-normalizable whereas the rests are normalizable. We study dynamics of vortex strings stretched between separated domain walls by using two methods, the moduli space (geodesic) approximation of full 1/4 BPS states and the charged particle approximation for string end points in the wall effective action. In the first method we explicitly obtain the effective Lagrangian in the strong coupling limit, which is written in terms of hypergeometric functions, and find the 90 deg. scattering for head-on collision. In the second method the domain wall effective action is assumed to be U(1) N gauge theory, and we find a good agreement between two methods for well-separated strings.

Isolation of the Cell Wall.

Science.gov (United States)

Canut, Hervé; Albenne, Cécile; Jamet, Elisabeth

2017-01-01

This chapter describes a method allowing the purification of the cell wall for studying both polysaccharides and proteins. The plant primary cell wall is mainly composed of polysaccharides (90-95 % in mass) and of proteins (5-10 %). At the end of growth, specialized cells may synthesize a lignified secondary wall composed of polysaccharides (about 65 %) and lignin (about 35 %). Due to its composition, the cell wall is the cellular compartment having the highest density and this property is used for its purification. It plays critical roles during plant development and in response to environmental constraints. It is largely used in the food and textile industries as well as for the production of bioenergy. All these characteristics and uses explain why its study as a true cell compartment is of high interest. The proposed method of purification can be used for large amount of material but can also be downscaled to 500 mg of fresh material. Tools for checking the quality of the cell wall preparation, such as protein analysis and microscopy observation, are also provided.

Wall Construction; Carpentry: 901892.

Science.gov (United States)

Dade County Public Schools, Miami, FL.

The curriculum guide outlines a course designed to provide instruction in floor and wall layout, and in the diverse methods and construction of walls. Upon completion of this course the students should have acquired a knowledge of construction plans and structural foundations in addition to a basic knowledge of mathematics. The course consists of…

Implementing Green Walls in Schools

Directory of Open Access Journals (Sweden)

Michael B. McCullough

2018-06-01

Full Text Available Numerous studies in applied pedagogical design have shown that, at all educational levels, direct exposure to the natural environment can enhance learning by improving student attention and behaviors. Implementing green walls—a “vertical garden,” or “living wall” interior wall that typically includes greenery, a growing medium (soil or substrate and a water delivery system—provides environmental health benefits, but also provides a practical application within classrooms for minimizing directed attention fatigue in students by connecting them to “outdoor nature” within the indoor environment. Hands-on “project-based” learning is another pedagogical strategy that has proved to be effective across the spectrum of educational levels and across subject areas. Green walls have the potential to inspire critical thinking through a combination of project-based learning strategies and environmental education. The authors have outlined a curriculum involving the implementation of an indoor living wall system within a classroom-learning environment, incorporating project-based learning modules that interact with the wall. In conjunction with the passive health benefits of a green wall, project-based curriculum models can connect students interactively with indoor nature and have the potential to inspire real-world thinking related to science, technology, engineering, art, and mathematics fields within the indoor learning environment. Through a combination of these passive and interactive modes, students are connected to nature in the indoor environment regardless of weather conditions outdoors. Future research direction could include post-construction studies of the effectiveness of project-based curricula related to living walls, and the long-term impacts of implementing green walls in classrooms on school achievement and student behaviors.

Results obtained during wall breaching research

CSIR Research Space (South Africa)

Hattingh, S

2008-11-01

Full Text Available To understand the physics of what is happening inside the wall directly after the detonation and the application of this knowledge in the improvement of the charge Measure the shock/stress waves in the masonry material and then in the wall as a whole... to maximise the effect of the charges on the walls and to broaden the knowledge of the physics of shock and stress waves. The thickness and characteristics of walls are not usually known in an operation. The effect of the charges on real buildings is still...

Glycoprotein component of plant cell walls

International Nuclear Information System (INIS)

Cooper, J.B.; Chen, J.A.; Varner, J.E.

1984-01-01

The primary wall surrounding most dicotyledonous plant cells contains a hydroxyproline-rich glycoprotein (HRGP) component named extensin. A small group of glycopeptides solubilized from isolated cell walls by proteolysis contained a repeated pentapeptide glycosylated by tri- and tetraarabinosides linked to hydroxyproline and, by galactose, linked to serine. Recently, two complementary approaches to this problem have provided results which greatly increase the understanding of wall extensin. In this paper the authors describe what is known about the structure of soluble extensin secreted into the walls of the carrot root cells

Sea ice contribution to the air-sea CO(2) exchange in the Arctic and Southern Oceans

DEFF Research Database (Denmark)

Rysgaard...[], Søren; Bendtsen, Jørgen; Delille, B.

2011-01-01

Although salt rejection from sea ice is a key process in deep-water formation in ice-covered seas, the concurrent rejection of CO(2) and the subsequent effect on air-sea CO(2) exchange have received little attention. We review the mechanisms by which sea ice directly and indirectly controls the air......-sea CO(2) exchange and use recent measurements of inorganic carbon compounds in bulk sea ice to estimate that oceanic CO(2) uptake during the seasonal cycle of sea-ice growth and decay in ice-covered oceanic regions equals almost half of the net atmospheric CO(2) uptake in ice-free polar seas. This sea......-sea CO(2) exchange during winter, and (3) release of CO(2)-depleted melt water with excess total alkalinity during sea-ice decay and (4) biological CO(2) drawdown during primary production in sea ice and surface oceanic waters....

Zooplankton community structure in the Yellow Sea and East China Sea in autumn

Directory of Open Access Journals (Sweden)

Hongju Chen

2015-12-01

Full Text Available Abstract Study on zooplankton spatial distribution is essential for understanding food web dynamics in marine ecosystems and fishery management. Here we elucidated the composition and distribution of large mesozooplankton on the continental shelf of the Yellow Sea and East China Sea, and explored the zooplankton community structure in these water masses. Sixty vertical hauls (bottom or 200 m in deep water to surface using a ring net (diameter 0.8 m, 505-μm mesh were exploited in November 2007. The biogeographic patterns of zooplankton communities were investigated using multivariate analysis methods; copepod biodiversity was analyzed using univariate indices. Copepods and protozoans were dominate in the communities. Based on the species composition, we divided the study areas into six station groups. Significant differences in zooplankton assemblages were detected between the Yellow Sea and East China Sea. Species richness was higher in East China Sea groups than those in Yellow Sea, whereas taxonomic distinctness was higher in Yellow Sea than in East China Sea. There was a clear relationship between the species composition and water mass group.

Taxonomic research on deep-sea macrofauna in the South China Sea using the Chinese deep-sea submersible Jiaolong.

Science.gov (United States)

Li, Xinzheng

2017-07-01

This paper reviews the taxonomic and biodiversity studies of deep-sea invertebrates in the South China Sea based on the samples collected by the Chinese manned deep-sea submersible Jiaolong. To date, 6 new species have been described, including the sponges Lophophysema eversa, Saccocalyx microhexactin and Semperella jiaolongae as well as the crustaceans Uroptychus jiaolongae, Uroptychus spinulosus and Globospongicola jiaolongi; some newly recorded species from the South China Sea have also been reported. The Bathymodiolus platifrons-Shinkaia crosnieri deep-sea cold seep community has been reported by Li (2015), as has the mitochondrial genome of the glass sponge L. eversa by Zhang et al. (2016). The population structures of two dominant species, the shrimp Shinkaia crosnieri and the mussel Bathymodiolus platifrons, from the cold seep Bathymodiolus platifrons-Shinkaia crosnieri community in the South China Sea and the hydrothermal vents in the Okinawa Trough, were compared using molecular analysis. The systematic position of the shrimp genus Globospongicola was discussed based on 16S rRNA gene sequences. © 2017 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Bacterial cell wall composition and the influence of antibiotics by cell-wall and whole-cell NMR

Science.gov (United States)

Romaniuk, Joseph A. H.; Cegelski, Lynette

2015-01-01

The ability to characterize bacterial cell-wall composition and structure is crucial to understanding the function of the bacterial cell wall, determining drug modes of action and developing new-generation therapeutics. Solid-state NMR has emerged as a powerful tool to quantify chemical composition and to map cell-wall architecture in bacteria and plants, even in the context of unperturbed intact whole cells. In this review, we discuss solid-state NMR approaches to define peptidoglycan composition and to characterize the modes of action of old and new antibiotics, focusing on examples in Staphylococcus aureus. We provide perspectives regarding the selected NMR strategies as we describe the exciting and still-developing cell-wall and whole-cell NMR toolkit. We also discuss specific discoveries regarding the modes of action of vancomycin analogues, including oritavancin, and briefly address the reconsideration of the killing action of β-lactam antibiotics. In such chemical genetics approaches, there is still much to be learned from perturbations enacted by cell-wall assembly inhibitors, and solid-state NMR approaches are poised to address questions of cell-wall composition and assembly in S. aureus and other organisms. PMID:26370936

Mechanism of bubble detachment from vibrating walls

Energy Technology Data Exchange (ETDEWEB)

Kim, Dongjun; Park, Jun Kwon, E-mail: junkeun@postech.ac.kr; Kang, Kwan Hyoung [Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang 790-784 (Korea, Republic of); Kang, In Seok [Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang 790-784 (Korea, Republic of)

2013-11-15

We discovered a previously unobserved mechanism by which air bubbles detach from vibrating walls in glasses containing water. Chaotic oscillation and subsequent water jets appeared when a wall vibrated at greater than a critical level. Wave forms were developed at water-air interface of the bubble by the wall vibration, and water jets were formed when sufficiently grown wave-curvatures were collapsing. Droplets were pinched off from the tip of jets and fell to the surface of the glass. When the solid-air interface at the bubble-wall attachment point was completely covered with water, the bubble detached from the wall. The water jets were mainly generated by subharmonic waves and were generated most vigorously when the wall vibrated at the volume resonant frequency of the bubble. Bubbles of specific size can be removed by adjusting the frequency of the wall's vibration.

Turbine airfoil having near-wall cooling insert

Science.gov (United States)

Martin, Jr., Nicholas F.; Wiebe, David J.

2017-09-12

A turbine airfoil is provided with at least one insert positioned in a cavity in an airfoil interior. The insert extends along a span-wise extent of the turbine airfoil and includes first and second opposite faces. A first near-wall cooling channel is defined between the first face and a pressure sidewall of an airfoil outer wall. A second near-wall cooling channel is defined between the second face and a suction sidewall of the airfoil outer wall. The insert is configured to occupy an inactive volume in the airfoil interior so as to displace a coolant flow in the cavity toward the first and second near-wall cooling channels. A locating feature engages the insert with the outer wall for supporting the insert in position. The locating feature is configured to control flow of the coolant through the first or second near-wall cooling channel.

Arctic sea ice decline: Projected changes in timing and extent of sea ice in the Bering and Chukchi Seas

Science.gov (United States)

Douglas, David C.

2010-01-01

The Arctic region is warming faster than most regions of the world due in part to increasing greenhouse gases and positive feedbacks associated with the loss of snow and ice cover. One consequence has been a rapid decline in Arctic sea ice over the past 3 decades?a decline that is projected to continue by state-of-the-art models. Many stakeholders are therefore interested in how global warming may change the timing and extent of sea ice Arctic-wide, and for specific regions. To inform the public and decision makers of anticipated environmental changes, scientists are striving to better understand how sea ice influences ecosystem structure, local weather, and global climate. Here, projected changes in the Bering and Chukchi Seas are examined because sea ice influences the presence of, or accessibility to, a variety of local resources of commercial and cultural value. In this study, 21st century sea ice conditions in the Bering and Chukchi Seas are based on projections by 18 general circulation models (GCMs) prepared for the fourth reporting period by the Intergovernmental Panel on Climate Change (IPCC) in 2007. Sea ice projections are analyzed for each of two IPCC greenhouse gas forcing scenarios: the A1B `business as usual? scenario and the A2 scenario that is somewhat more aggressive in its CO2 emissions during the second half of the century. A large spread of uncertainty among projections by all 18 models was constrained by creating model subsets that excluded GCMs that poorly simulated the 1979-2008 satellite record of ice extent and seasonality. At the end of the 21st century (2090-2099), median sea ice projections among all combinations of model ensemble and forcing scenario were qualitatively similar. June is projected to experience the least amount of sea ice loss among all months. For the Chukchi Sea, projections show extensive ice melt during July and ice-free conditions during August, September, and October by the end of the century, with high agreement

South China Sea

Energy Technology Data Exchange (ETDEWEB)

Morton, Brian [Hong Kong Univ., Swire Inst. of Marine Science, Hong Kong (China); Hong Kong Univ., Dept. of Ecology and Biodiversity, Hong Kong (China); Blackmore, Graham [Hong Kong Univ. of Science and Technology, Dept. of Biology, Hong Kong (China)

2001-07-01

The South China Sea is poorly understood in terms of its marine biota, ecology and the human impacts upon it. What is known is most often contained in reports and workshops and conference documents that are not available to the wider scientific community. The South China Sea has an area of some 3.3 million km{sup 2} and depths range from the shallowest coastal fringe to 5377m in the Manila Trench. It is also studded with numerous islets, atolls and reefs many of which are just awash at low tide. It is largely confined within the Tropic of Cancer and, therefore, experiences a monsoonal climate being influenced by the Southwest Monsoon in summer and the Northeast Monsoon in winter. The South China Sea is a marginal sea and, therefore, largely surrounded by land. Countries that have a major influence on and claims to the sea include China, Malaysia, the Philippines and Vietnam, although Thailand, Indonesia and Taiwan have some too. The coastal fringes of the South China Sea are home to about 270 million people that have had some of the fastest developing and most vibrant economics on the globe. Consequently, anthropogenic impacts, such as over-exploitation of resources and pollution, are anticipated to be huge although, in reality, relatively little is known about them. The Indo-West Pacific biogeographic province, at the centre of which the South China Sea lies, is probably the world's most diverse shallow-water marine area. Of three major nearshore habitat types, i.e., coral reefs, mangroves and seagrasses, 45 mangrove species out of a global total of 51, most of the currently recognised 70 coral genera and 20 of 50 known seagrass species have been recorded from the South China Sea. The island groups of the South China Sea are all disputed and sovereignty is claimed over them by a number of countries. Conflicts have in recent decades arisen over them because of perceived national rights. It is perhaps because of this that so little research has been undertaken

South China Sea

Science.gov (United States)

Morton, Brian; Blackmore, Graham

2001-01-01

The South China Sea is poorly understood in terms of its marine biota, ecology and the human impacts upon it. What is known is most often contained in reports and workshop and conference documents that are not available to the wider scientific community. The South China Sea has an area of some 3.3 million km2 and depths range from the shallowest coastal fringe to 5377 m in the Manila Trench. It is also studded with numerous islets, atolls and reefs many of which are just awash at low tide. It is largely confined within the Tropic of Cancer and, therefore, experiences a monsoonal climate being influenced by the Southwest Monsoon in summer and the Northeast Monsoon in winter. The South China Sea is a marginal sea and, therefore, largely surrounded by land. Countries that have a major influence on and claims to the sea include China, Malaysia, the Philippines and Vietnam, although Thailand, Indonesia and Taiwan have some too. The coastal fringes of the South China Sea are home to about 270 million people that have had some of the fastest developing and most vibrant economies on the globe. Consequently, anthropogenic impacts, such as over-exploitation of resources and pollution, are anticipated to be huge although, in reality, relatively little is known about them. The Indo-West Pacific biogeographic province, at the centre of which the South China Sea lies, is probably the world's most diverse shallow-water marine area. Of the three major nearshore habitat types, i.e., coral reefs, mangroves and seagrasses, 45 mangrove species out of a global of 51, most of the currently recognised 70 coral genera and 20 of 50 known seagrass species have been recorded from the South China Sea. The island groups of the South China Sea are all disputed and sovereignty is claimed over them by a number of countries. Conflicts have in recent decades arisen over them because of perceived national rights. It is perhaps because of this that so little research has been undertaken on the South

Enrichment, Distribution of Vanadium-Containing Protein in Vanadium-Enriched Sea Cucumber Apostichopus japonicus and the Ameliorative Effect on Insulin Resistance.

Science.gov (United States)

Liu, Yanjun; Zhou, Qingxin; Zhao, Yanlei; Wang, Yiming; Wang, Yuming; Wang, Jingfeng; Xu, Jie; Xue, Changhu

2016-05-01

Sea cucumbers are a potential source of natural organic vanadium that may improve insulin resistance. In this work, vanadium was accumulated rapidly in blood, body wall, and intestine by sea cucumber Apostichopus japonicus. Furthermore, water-soluble vanadium-containing proteins, the main form of the organic vanadium, were tentatively accumulated and isolated by a bioaccumulation experiment. It was also designed to evaluate the beneficial effect of vanadium-containing proteins (VCPs) from sea cucumber rich in vanadium on the development of hyperglycemia and insulin resistance in C57BL/6J mice fed with a high-fat high-sucrose diet (HFSD). HFSD mice treated with VCPs significantly decreased fasting blood glucose, serum insulin, and HOMA-IR values as compared to HFSD mice, respectively. Serum adiponectin, resistin, TNF-α, and leptin levels in insulin-resistant mice were dramatically reduced by a VCP supplement. These results show an ameliorative effect on insulin resistance by treatment with VCPs. Such compound seems to be a valuable therapy to achieve and/or maintain glycemic control and therapeutic agents in the treatment arsenal for insulin resistance and type 2 diabetes.

An Evaluation on the Ratio of Plant to Animal Protein in the Diet of Juvenile Sea Cucumber (Apostichopus japonicus): Growth, Nutrient Digestibility and Nonspecific Immunity

Science.gov (United States)

Bao, Pengyun; Li, Xiaoyu; Xu, Yongping

2018-05-01

This study was conducted to evaluate the effects of plant/animal (P/A) protein ratios (viz.1:4, 1:3, 1:2, 1:1,2:1, 3:1, 4:1) on growth performance, body composition, apparent digestibility of diets, and nonspecific immunity of juvenile sea cucumber (Apostichopus japonicus). Sea cucumbers were divided into 21 plastic tanks, and each tank was stocked with 15 individuals (initial weight: about 23.73 g). Each feed was allocated to three replicates of sea cucumbers. The feeding experiment lasted for 50 days. Results indicated that weight gain rate (WGR) and body wall weight (BWW) significantly increased as dietary ratio of P/A increased from 1:4 to 3:1, and then decreased significantly with further increase of this ratio (P 0.05). The apparent digestibility of dry matter, protein and lipid increased with ratio of P/A increasing from 1:4 to 2:1 (P protein (1:1-3:1) significantly increased the growth performance, apparent digestibility, and nonspecific immunity of sea cucumber. This will contribute to improving the feed formulation for juvenile cucumbers.

Evolution of the Stability Work from Classic Retaining Walls to Mechanically Stabilized Earth Walls

Directory of Open Access Journals (Sweden)

Anghel Stanciu

2008-01-01

Full Text Available For the consolidation of soil mass and the construction of the stability works for roads infrastructure it was studied the evolution of these kinds of works from classical retaining walls - common concrete retaining walls, to the utilization in our days of the modern and competitive methods - mechanically stabilized earth walls. Like type of execution the variety of the reinforced soil is given by the utilization of different types of reinforcing inclusions (steel strips, geosynthetics, geogrids or facing (precast concrete panels, dry cast modular blocks, metal sheets and plates, gabions, and wrapped sheets of geosynthetics.

Estimation of bladder wall location in ultrasound images.

Science.gov (United States)

Topper, A K; Jernigan, M E

1991-05-01

A method of automatically estimating the location of the bladder wall in ultrasound images is proposed. Obtaining this estimate is intended to be the first stage in the development of an automatic bladder volume calculation system. The first step in the bladder wall estimation scheme involves globally processing the images using standard image processing techniques to highlight the bladder wall. Separate processing sequences are required to highlight the anterior bladder wall and the posterior bladder wall. The sequence to highlight the anterior bladder wall involves Gaussian smoothing and second differencing followed by zero-crossing detection. Median filtering followed by thresholding and gradient detection is used to highlight as much of the rest of the bladder wall as was visible in the original images. Then a 'bladder wall follower'--a line follower with rules based on the characteristics of ultrasound imaging and the anatomy involved--is applied to the processed images to estimate the bladder wall location by following the portions of the bladder wall which are highlighted and filling in the missing segments. The results achieved using this scheme are presented.

Development of fatty acid biomarkers for the identification of wild and aquacultured sea cucumber ( Apostichopus japonicus)

Science.gov (United States)

Zadorozhnyj, P. A.; Pivnenko, T. N.; Kovalev, N. N.

2016-02-01

In this study, the fatty acids (FAs) of the organs and tissues of sea cucumber ( Apostichopus japonicus) were profiled in order to compare the FA composition of sea cucumber collected from natural habitat (wild) and cages (cultured). The differences in FA contents in dermomuscular tube, peripharyngeal annulus, gonad and intestine (with or without content) between the wild and the cultured were determined. The main fatty acids in all organs and tissues were 20:5n-3, 16:1n-7, 20:4n-6, 22:6n-3, 18:0, and 18:1n-7. The basically different FAs of body wall and digestive tube were 16:1n-7, 18:1n-9 and 20:1n-11. The ratio of saturated to mono- and polyunsaturated FAs in digestive tube was independent on inside content while there was a redistribution of the total amount of n-3 and n-6 fatty acids. The comparison of FA composition of the wild and the cultured sea cucumber showed that 20:5n-3, 16:1n-7 and 18:1n-7 predominated the wild while 20:4n-6 predominated the cultured. The content of branched-chain fatty acids in the wild was 3%-4% and about 9% in the cultured. The possible FAs for identifying the wild and the cultured sea cucumbers were selected. It was suggested that the indexes such as the ratio of either (n-3:n-6) to (n-7:n-6) or (n-3) + (n-7) to (n-6) may serve as the biomarkers distinguishing the wild and the cultured sea cucumber.

Arabidopsis Regenerating Protoplast: A Powerful Model System for Combining the Proteomics of Cell Wall Proteins and the Visualization of Cell Wall Dynamics

Science.gov (United States)

Yokoyama, Ryusuke; Kuki, Hiroaki; Kuroha, Takeshi; Nishitani, Kazuhiko

2016-01-01

The development of a range of sub-proteomic approaches to the plant cell wall has identified many of the cell wall proteins. However, it remains difficult to elucidate the precise biological role of each protein and the cell wall dynamics driven by their actions. The plant protoplast provides an excellent means not only for characterizing cell wall proteins, but also for visualizing the dynamics of cell wall regeneration, during which cell wall proteins are secreted. It therefore offers a unique opportunity to investigate the de novo construction process of the cell wall. This review deals with sub-proteomic approaches to the plant cell wall through the use of protoplasts, a methodology that will provide the basis for further exploration of cell wall proteins and cell wall dynamics. PMID:28248244

Radioactivity in the Arctic Seas. Report for the International Arctic Seas Assessment Project (IASAP)

International Nuclear Information System (INIS)

1999-04-01

This report provides comprehensive information on environmental conditions in the Arctic Seas as required for the study of possible radiological consequences from dumped high level radioactive wastes in the Kara Sea. The report describes the oceanography of the regions, with emphasis on the Kara and Barents Seas, including the East Novaya Zemlya Fjords. The ecological description concentrates on biological production, marine food-weds and fisheries in the Arctic Seas. The report presents data on radionuclide concentrations in the Kara and Barents Seas and uses these data to estimate the inventories of radionuclides currently in the marine environment of the Kara and Barents Seas

Low-rise shear wall failure modes

International Nuclear Information System (INIS)

Farrar, C.R.; Hashimoto, P.S.; Reed, J.W.

1991-01-01

A summary of the data that are available concerning the structural response of low-rise shear walls is presented. This data will be used to address two failure modes associated with the shear wall structures. First, data concerning the seismic capacity of the shear walls with emphasis on excessive deformations that can cause equipment failure are examined. Second, data concerning the dynamic properties of shear walls (stiffness and damping) that are necessary to compute the seismic inputs to attached equipment are summarized. This case addresses the failure of equipment when the structure remains functional. 23 refs

Applied radiotracer techniques for studying pollutant bioaccumulation in selected marine organisms (jellyfish, crabs and sea stars)

International Nuclear Information System (INIS)

Fowler, S.W.; Teyssie, J.-L.; Cotret, O.; Danis, B.; Warnau, M.; Rouleau, C.

2004-01-01

Obtaining specific information on contaminant biokinetics in marine biota is often necessary for properly interpreting monitoring data on trace contaminant levels in bioindicator species living under varying environmental conditions. Radiotracers have been employed in laboratory experiments to assess the uptake, distribution and retention of selected heavy metals and PCB congeners in three potential marine bioindicators occupying different ecological niches in the coastal zone. Pelagic and benthic jellyfish readily accumulated Co, Ag, Zn, Cd, 137 Cs and 241 Am from both water and food and retained them with biological half-lives (Tb1/2) ranging from a few days to several weeks. Zinc and silver were accumulated to the greatest degree (CF ∼ 4 · 10 2 ), with benthic jellyfish having a greater affinity for metals than the pelagic species. Results from light-dark experiments indicate that the enhanced metal uptake in the benthic jellyfish is due to the presence of endosymbiotic photosynthetic zooxanthellae situated in the arms of organisms. Shore crabs ingesting Ag, a sewage-related contaminant, readily accumulated the metal with male crabs assimilating some 71% and female crabs 51% of the Ag from their food. Moreover, the assimilated fraction of Ag remained virtually immobile in their tissues as evidenced by an extremely long Tb1/2 for depuration of 7.3 years. Sea stars exposed to 14 C-labelled PCB congener no. 153 in sea water accumulated the congener mainly in the body wall and podia reaching lipid weight CFs that ranged between approximately 2 · 10 5 to 4 · 10 5 . In contrast, following exposure in radiolabelled sediments, the corresponding PCB transfer factors in the same tissues were much lower, viz., 3 · 10 2 to 5 · 10 2 . Nevertheless, regardless of the exposure mode, CFs of PCB in the other tissues (digestive system, gonads, pyloric and rectal caeca) were consistently one to two orders of magnitude lower, an observation which suggests that sea star body

Late Holocene sea ice conditions in Herald Canyon, Chukchi Sea

Science.gov (United States)

Pearce, C.; O'Regan, M.; Rattray, J. E.; Hutchinson, D. K.; Cronin, T. M.; Gemery, L.; Barrientos, N.; Coxall, H.; Smittenberg, R.; Semiletov, I. P.; Jakobsson, M.

2017-12-01

Sea ice in the Arctic Ocean has been in steady decline in recent decades and, based on satellite data, the retreat is most pronounced in the Chukchi and Beaufort seas. Historical observations suggest that the recent changes were unprecedented during the last 150 years, but for a longer time perspective, we rely on the geological record. For this study, we analyzed sediment samples from two piston cores from Herald Canyon in the Chukchi Sea, collected during the 2014 SWERUS-C3 Arctic Ocean Expedition. The Herald Canyon is a local depression across the Chukchi Shelf, and acts as one of the main pathways for Pacific Water to the Arctic Ocean after entering through the narrow and shallow Bering Strait. The study site lies at the modern-day seasonal sea ice minimum edge, and is thus an ideal location for the reconstruction of past sea ice variability. Both sediment cores contain late Holocene deposits characterized by high sediment accumulation rates (100-300 cm/kyr). Core 2-PC1 from the shallow canyon flank (57 m water depth) is 8 meter long and extends back to 4200 cal yrs BP, while the upper 3 meters of Core 4-PC1 from the central canyon (120 mwd) cover the last 3000 years. The chronologies of the cores are based on radiocarbon dates and the 3.6 ka Aniakchak CFE II tephra, which is used as an absolute age marker to calculate the marine radiocarbon reservoir age. Analysis of biomarkers for sea ice and surface water productivity indicate stable sea ice conditions throughout the entire late Holocene, ending with an abrupt increase of phytoplankton sterols in the very top of both sediment sequences. The shift is accompanied by a sudden increase in coarse sediments (> 125 µm) and a minor change in δ13Corg. We interpret this transition in the top sediments as a community turnover in primary producers from sea ice to open water biota. Most importantly, our results indicate that the ongoing rapid ice retreat in the Chukchi Sea of recent decades was unprecedented during the

Coastal seas as resource for Blue Growth - SmartSea project

Science.gov (United States)

Kotilainen, Aarno; Alvi, Kimmo; Boman, Anton; Hämäläinen, Jyrki; Kaskela, Anu; Rantataro, Jyrki; Vallius, Henry; Virtasalo, Joonas

2017-04-01

Blue growth is a long term strategy of the European Union (EU) to enhance the sustainable growth of the maritime sector. Our surrounding seas have been drivers for the European economy for a long time, but still they have great potential for further exploiting of natural resources and economic growth. Especially if the growth can be achieved in an environmentally sustainable way, benefits are obvious. It has been estimated that improvement of the state of the Baltic Sea would until 2030 create 900 000 jobs in the whole Baltic Sea area, mainly in Blue Tech, tourism, real estate and building businesses (Dahlgren et al. 2015). However, coastal seas already experience multiple stressors like off-shore construction, pollution, eutrophication, shipping, over-fishing, and climate change. In order to obtain sustainable Blue Growth, it is necessary to localize and assess the current maritime activities, estimate their growth potential, and investigate their present and future effects on each other and on the marine environment. The purpose of the SmartSea project is to support the growth of commercial marine activities in the Gulf of Bothnia region, in the northern Baltic Sea. The Gulf of Bothnia is an essential resource in terms of fish farming and wind power, for example, and it is also possible to make use of the geological resources of the gulf. Moreover, the rapid growth of the commercial marine activities and the consequences of the climate change may lead to conflicts between the different activities and harm the marine ecosystem of the Gulf of Bothnia. The SmartSea project aims to identify these risks and find solutions for the sustainable use of the sea. SmartSea project is funded by the Strategic Research Council of Academy of Finland, grant No: 292 985. The project will last for six years (2015-2020) and its funding totals nearly 8 million euros. The project involves close to 40 researchers from eight different institutions: the Finnish Meteorological Institute

Sunspot Light Walls Suppressed by Nearby Brightenings

Energy Technology Data Exchange (ETDEWEB)

Yang, Shuhong; Zhang, Jun; Hou, Yijun; Li, Xiaohong [CAS Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Erdélyi, Robertus [Solar Physics and Space Plasma Research Centre, School of Mathematics and Statistics, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Yan, Limei, E-mail: shuhongyang@nao.cas.cn [Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029 (China)

2017-07-01

Light walls, as ensembles of oscillating bright structures rooted in sunspot light bridges, have not been well studied, although they are important for understanding sunspot properties. Using the Interface Region Imaging Spectrograph and Solar Dynamics Observatory observations, here we study the evolution of two oscillating light walls each within its own active region (AR). The emission of each light wall decays greatly after the appearance of adjacent brightenings. For the first light wall, rooted within AR 12565, the average height, amplitude, and oscillation period significantly decrease from 3.5 Mm, 1.7 Mm, and 8.5 minutes to 1.6 Mm, 0.4 Mm, and 3.0 minutes, respectively. For the second light wall, rooted within AR 12597, the mean height, amplitude, and oscillation period of the light wall decrease from 2.1 Mm, 0.5 Mm, and 3.0 minutes to 1.5 Mm, 0.2 Mm, and 2.1 minutes, respectively. Particularly, a part of the second light wall even becomes invisible after the influence of a nearby brightening. These results reveal that the light walls are suppressed by nearby brightenings. Considering the complex magnetic topology in light bridges, we conjecture that the fading of light walls may be caused by a drop in the magnetic pressure, where the flux is canceled by magnetic reconnection at the site of the nearby brightening. Another hypothesis is that the wall fading is due to the suppression of driver source ( p -mode oscillation), resulting from the nearby avalanche of downward particles along reconnected brightening loops.

Projecting future sea level

Science.gov (United States)

Cayan, Daniel R.; Bromirski, Peter; Hayhoe, Katharine; Tyree, Mary; Dettinger, Mike; Flick, Reinhard

2006-01-01

California’s coastal observations and global model projections indicate that California’s open coast and estuaries will experience increasing sea levels over the next century. Sea level rise has affected much of the coast of California, including the Southern California coast, the Central California open coast, and the San Francisco Bay and upper estuary. These trends, quantified from a small set of California tide gages, have ranged from 10–20 centimeters (cm) (3.9–7.9 inches) per century, quite similar to that estimated for global mean sea level. So far, there is little evidence that the rate of rise has accelerated, and the rate of rise at California tide gages has actually flattened since 1980, but projections suggest substantial sea level rise may occur over the next century. Climate change simulations project a substantial rate of global sea level rise over the next century due to thermal expansion as the oceans warm and runoff from melting land-based snow and ice accelerates. Sea level rise projected from the models increases with the amount of warming. Relative to sea levels in 2000, by the 2070–2099 period, sea level rise projections range from 11–54 cm (4.3–21 in) for simulations following the lower (B1) greenhouse gas (GHG) emissions scenario, from 14–61 cm (5.5–24 in) for the middle-upper (A2) emission scenario, and from 17–72 cm (6.7–28 in) for the highest (A1fi) scenario. In addition to relatively steady secular trends, sea levels along the California coast undergo shorter period variability above or below predicted tide levels and changes associated with long-term trends. These variations are caused by weather events and by seasonal to decadal climate fluctuations over the Pacific Ocean that in turn affect the Pacific coast. Highest coastal sea levels have occurred when winter storms and Pacific climate disturbances, such as El Niño, have coincided with high astronomical tides. This study considers a range of projected future

Semiautomatic vessel wall detection and quantification of wall thickness in computed tomography images of human abdominal aortic aneurysms

International Nuclear Information System (INIS)

Shum, Judy; DiMartino, Elena S.; Goldhammer, Adam; Goldman, Daniel H.; Acker, Leah C.; Patel, Gopal; Ng, Julie H.; Martufi, Giampaolo; Finol, Ender A.

2010-01-01

Purpose: Quantitative measurements of wall thickness in human abdominal aortic aneurysms (AAAs) may lead to more accurate methods for the evaluation of their biomechanical environment. Methods: The authors describe an algorithm for estimating wall thickness in AAAs based on intensity histograms and neural networks involving segmentation of contrast enhanced abdominal computed tomography images. The algorithm was applied to ten ruptured and ten unruptured AAA image data sets. Two vascular surgeons manually segmented the lumen, inner wall, and outer wall of each data set and a reference standard was defined as the average of their segmentations. Reproducibility was determined by comparing the reference standard to lumen contours generated automatically by the algorithm and a commercially available software package. Repeatability was assessed by comparing the lumen, outer wall, and inner wall contours, as well as wall thickness, made by the two surgeons using the algorithm. Results: There was high correspondence between automatic and manual measurements for the lumen area (r=0.978 and r=0.996 for ruptured and unruptured aneurysms, respectively) and between vascular surgeons (r=0.987 and r=0.992 for ruptured and unruptured aneurysms, respectively). The authors' automatic algorithm showed better results when compared to the reference with an average lumen error of 3.69%, which is less than half the error between the commercially available application Simpleware and the reference (7.53%). Wall thickness measurements also showed good agreement between vascular surgeons with average coefficients of variation of 10.59% (ruptured aneurysms) and 13.02% (unruptured aneurysms). Ruptured aneurysms exhibit significantly thicker walls (1.78±0.39 mm) than unruptured ones (1.48±0.22 mm), p=0.044. Conclusions: While further refinement is needed to fully automate the outer wall segmentation algorithm, these preliminary results demonstrate the method's adequate reproducibility and

A comparative analysis of two Early Palaeozoic marine impact structures in Estonia, Baltic Sea: Neugrund and Kärdla

Directory of Open Access Journals (Sweden)

Sten Suuroja

2013-07-01

Full Text Available Kärdla and Neugrund are two Early Palaeozoic offshore impact structures located some 50 km apart along the Estonian coast of the Baltic Sea. They share many similarities but differing features are also found. The Kärdla impact structure is located at the NE coastof Hiiumaa Island (58°58’N, 22°46’E. The inner crater has a 4 km rim-to-rim diameter and a c. 130 m high central uplift, surrounded by a ring fault, c. 12 km in diameter. The well-preserved buried inner crater is outlined in the landscape by a circular ridge of upliftedbedrock. The perimeter of the outer crater is outlined on the seafloor by a semicircular ridge of narrow shoals. The variable height of the rim wall (50–240 m above the crystalline basement level and the asymmetric location of the inner crater is obviously a result of an oblique impact in a layered target and partial collapse of the rim wall. Shortly after the impact in a shallow epicontinental sea during Late Ordovician time (c. 455 My, calcareous biodetritic muds were deposited and the crater was buried. The Neugrund impact structure is located in the seabed at the entrance of the Gulf of Finland (59°20’N, 23°31’E. The inner crater has a 7 km rim-to-rim diameter and the outer limit of the structure passes through the Osmussaar Island to the southwest of the impact centre. The crater wasburied in a shallow epicontinental sea with siliciclastic deposition shortly after the impact at Early Cambrian time, c. 535 My. It was partially re-exposed by erosion during Pliocene. The target had a three-layered composition: Precambrian metamorphic rocks covered byEdiacaran and Early Cambrian siliciclastic rocks (c. 150 m and water (c. 100 m. The structure has been studied with seismoacoustic and sidescan sonar profiling, and by diving and sampling of submarine outcrops. Several hundred samples of impact breccias have been collected and investigated from erratic boulders distributed by glacial action in the west

Double wall steam generator tubing

International Nuclear Information System (INIS)

Padden, T.R.; Uber, C.F.

1983-01-01

Double-walled steam generator tubing for the steam generators of a liquid metal cooled fast breeder reactor prevents sliding between the surfaces due to a mechanical interlock. Forces resulting from differential thermal expansion between the outer tube and the inner tube are insufficient in magnitude to cause shearing of base metal. The interlock is formed by jointly drawing the tubing, with the inside wall of the outer tube being already formed with grooves. The drawing causes the outer wall of the inner tube to form corrugations locking with the grooves. (author)

Connection of thin-walled casings

Energy Technology Data Exchange (ETDEWEB)

Druyan, V.M.; Grinev, A.F.; Gruzdev, V.D.; Perchanik, V.V.; Syplenko, V.T.

1981-08-28

A connection is suggested for castings which contains a nipple and coupling part with conical triangular threading. in order to improve the strength of the connection of thin-walled casings with ratio D/S>22, where D is the outer diameter of the casing, S is the thickness of the wall of the casing, the end of the pipe on the length from the end to the main plane of the thread is conical with constant thickness of the wall and conicity eqal to the conicity of the thread.

Air–Sea Interaction and Horizontal Circulation in the Red Sea

KAUST Repository

Bower, Amy S.

2015-01-01

This chapter discusses the horizontal circulation of the Red Sea and the surface meteorology that drives it, and recent satellite and in situ measurements from the region are used to illustrate properties of the Red Sea circulation and the atmospheric forcing. The surface winds over the Red Sea have rich spatial structure, with variations in speed and direction on both synoptic and seasonal timescales. Wintertime mountain-gap wind jets drive large heat losses and evaporation at some locations, with as much as 9 cm of evaporation in a week. The near-surface currents in the Red Sea exhibit similarly rich variability, with an energetic and complex flow field dominated by persistent, quasi-stationary eddies, and convoluted boundary currents. At least one quasi-stationary eddy pair is driven largely by winds blowing through a gap in the mountains (Tokar Gap), but numerical simulations suggest that much of the eddy field is driven by the interaction of the buoyancy-driven flow with topography. Recent measurements suggest that Gulf of Aden Intermediate Water (GAIW) penetrates further northward into the Red Sea than previously reported.

Making Your Music Word Wall Work

Science.gov (United States)

Leonhardt, Angela

2011-01-01

This article looks at what a word wall is and its use in the music classroom. The author outlines steps for creation of a word wall within the music classroom as well as the importance of such a resource. The author encourages the creation and consistent use of the word wall as leading to the development of stronger musicians and also independent,…

Satellite altimetry in sea ice regions - detecting open water for estimating sea surface heights

Science.gov (United States)

Müller, Felix L.; Dettmering, Denise; Bosch, Wolfgang

2017-04-01

The Greenland Sea and the Farm Strait are transporting sea ice from the central Arctic ocean southwards. They are covered by a dynamic changing sea ice layer with significant influences on the Earth climate system. Between the sea ice there exist various sized open water areas known as leads, straight lined open water areas, and polynyas exhibiting a circular shape. Identifying these leads by satellite altimetry enables the extraction of sea surface height information. Analyzing the radar echoes, also called waveforms, provides information on the surface backscatter characteristics. For example waveforms reflected by calm water have a very narrow and single-peaked shape. Waveforms reflected by sea ice show more variability due to diffuse scattering. Here we analyze altimeter waveforms from different conventional pulse-limited satellite altimeters to separate open water and sea ice waveforms. An unsupervised classification approach employing partitional clustering algorithms such as K-medoids and memory-based classification methods such as K-nearest neighbor is used. The classification is based on six parameters derived from the waveform's shape, for example the maximum power or the peak's width. The open-water detection is quantitatively compared to SAR images processed while accounting for sea ice motion. The classification results are used to derive information about the temporal evolution of sea ice extent and sea surface heights. They allow to provide evidence on climate change relevant influences as for example Arctic sea level rise due to enhanced melting rates of Greenland's glaciers and an increasing fresh water influx into the Arctic ocean. Additionally, the sea ice cover extent analyzed over a long-time period provides an important indicator for a globally changing climate system.

HVI Ballistic Performance Characterization of Non-Parallel Walls

Science.gov (United States)

Bohl, William; Miller, Joshua; Christiansen, Eric

2012-01-01

The Double-Wall, "Whipple" Shield [1] has been the subject of many hypervelocity impact studies and has proven to be an effective shield system for Micro-Meteoroid and Orbital Debris (MMOD) impacts for spacecraft. The US modules of the International Space Station (ISS), with their "bumper shields" offset from their pressure holding rear walls provide good examples of effective on-orbit use of the double wall shield. The concentric cylinder shield configuration with its large radius of curvature relative to separation distance is easily and effectively represented for testing and analysis as a system of two parallel plates. The parallel plate double wall configuration has been heavily tested and characterized for shield performance for normal and oblique impacts for the ISS and other programs. The double wall shield and principally similar Stuffed Whipple Shield are very common shield types for MMOD protection. However, in some locations with many spacecraft designs, the rear wall cannot be modeled as being parallel or concentric with the outer bumper wall. As represented in Figure 1, there is an included angle between the two walls. And, with a cylindrical outer wall, the effective included angle constantly changes. This complicates assessment of critical spacecraft components located within outer spacecraft walls when using software tools such as NASA's BumperII. In addition, the validity of the risk assessment comes into question when using the standard double wall shield equations, especially since verification testing of every set of double wall included angles is impossible.

Wall shear stress measurement of near-wall flow over inclined and curved boundaries by stereo interfacial particle image velocimetry

International Nuclear Information System (INIS)

Nguyen, Thien Duy; Wells, John Craig; Nguyen, Chuong Vinh

2010-01-01

In investigations of laminar or turbulent flows, wall shear is often important. Nevertheless, conventional particle image velocimetry (PIV) is difficult in near-wall regions. A near-wall measurement technique, named interfacial PIV (IPIV) [Nguyen, C., Nguyen, T., Wells, J., Nakayama, A., 2008. Proposals for PIV of near-wall flow over curved boundaries. In: Proceedings of 14th International Symposium on Applications of Laser Technique to Fluid Mechanics], handles curved boundaries by means of conformal transformation, directly measures the wall gradient, and yields the near-wall tangential velocity profile at one-pixel resolution. In this paper, we show the feasibility of extending IPIV to measure wall gradients by stereo reconstruction. First, we perform a test on synthetic images generated from a direct numerical simulation (DNS) snapshot of turbulent flow over sinusoidal bed. Comparative assessment of wall gradients derived by IPIV, stereo-IPIV and particle image distortion (PID) [Huang, H.T., Fiedler, H.E., Wang, J.J., 1993. Limitation and improvement of PIV. Experiments in Fluids 15(4), 263-273] is evaluated with DNS data. Also, the sensitivity of IPIV and stereo-IPIV results to the uncertainty of identified wall position is examined. As a practical application of IPIV and stereo-IPIV to experimental images, results from turbulent open channel flow over a backward-facing step are discussed in detail.

Sea Turtle Conservation on Bonaire. Sea Turtle Club Bonaire 1997. Project Report

NARCIS (Netherlands)

Schuit, M.; Put, van A.L.L.M.; Valkering, N.P.; Eijck, van T.J.W.

1998-01-01

The Sea Turtle Club Bonaire (STCB) is a non-governmental, non-profit organization. Its main goal is the conservation of the sea turtles that occur on Bonaire. To reach this goal, annual projects are undertaken, such as research and the promotion of public awareness on sea turtle conservation. The

Don't Forget the Abdominal Wall: Imaging Spectrum of Abdominal Wall Injuries after Nonpenetrating Trauma.

Science.gov (United States)

Matalon, Shanna A; Askari, Reza; Gates, Jonathan D; Patel, Ketan; Sodickson, Aaron D; Khurana, Bharti

2017-01-01

Abdominal wall injuries occur in nearly one of 10 patients coming to the emergency department after nonpenetrating trauma. Injuries range from minor, such as abdominal wall contusion, to severe, such as abdominal wall rupture with evisceration of abdominal contents. Examples of specific injuries that can be detected at cross-sectional imaging include abdominal muscle strain, tear, or hematoma, including rectus sheath hematoma (RSH); traumatic abdominal wall hernia (TAWH); and Morel-Lavallée lesion (MLL) (closed degloving injury). These injuries are often overlooked clinically because of (a) a lack of findings at physical examination or (b) distraction by more-severe associated injuries. However, these injuries are important to detect because they are highly associated with potentially grave visceral and vascular injuries, such as aortic injury, and because their detection can lead to the diagnosis of these more clinically important grave traumatic injuries. Failure to make a timely diagnosis can result in delayed complications, such as bowel hernia with potential for obstruction or strangulation, or misdiagnosis of an abdominal wall neoplasm. Groin injuries, such as athletic pubalgia, and inferior costochondral injuries should also be considered in patients with abdominal pain after nonpenetrating trauma, because these conditions may manifest with referred abdominal pain and are often included within the field of view at cross-sectional abdominal imaging. Radiologists must recognize and report acute abdominal wall injuries and their associated intra-abdominal pathologic conditions to allow appropriate and timely treatment. © RSNA, 2017.

The Ross Sea Dipole – temperature, snow accumulation and sea ice variability in the Ross Sea region, Antarctica, over the past 2700 years

Directory of Open Access Journals (Sweden)

N. A. N. Bertler

2018-02-01

Full Text Available High-resolution, well-dated climate archives provide an opportunity to investigate the dynamic interactions of climate patterns relevant for future projections. Here, we present data from a new, annually dated ice core record from the eastern Ross Sea, named the Roosevelt Island Climate Evolution (RICE ice core. Comparison of this record with climate reanalysis data for the 1979–2012 interval shows that RICE reliably captures temperature and snow precipitation variability in the region. Trends over the past 2700 years in RICE are shown to be distinct from those in West Antarctica and the western Ross Sea captured by other ice cores. For most of this interval, the eastern Ross Sea was warming (or showing isotopic enrichment for other reasons, with increased snow accumulation and perhaps decreased sea ice concentration. However, West Antarctica cooled and the western Ross Sea showed no significant isotope temperature trend. This pattern here is referred to as the Ross Sea Dipole. Notably, during the Little Ice Age, West Antarctica and the western Ross Sea experienced colder than average temperatures, while the eastern Ross Sea underwent a period of warming or increased isotopic enrichment. From the 17th century onwards, this dipole relationship changed. All three regions show current warming, with snow accumulation declining in West Antarctica and the eastern Ross Sea but increasing in the western Ross Sea. We interpret this pattern as reflecting an increase in sea ice in the eastern Ross Sea with perhaps the establishment of a modern Roosevelt Island polynya as a local moisture source for RICE.

ENHANCEMENT OF A SUNSPOT LIGHT WALL WITH EXTERNAL DISTURBANCES

Energy Technology Data Exchange (ETDEWEB)

Yang, Shuhong; Zhang, Jun [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Erdélyi, Robert, E-mail: shuhongyang@nao.cas.cn [Solar Physics and Space Plasma Research Centre, School of Mathematics and Statistics, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom)

2016-12-20

Based on the Interface Region Imaging Spectrograph observations, we study the response of a solar sunspot light wall to external disturbances. A flare occurrence near the light wall caused material to erupt from the lower solar atmosphere into the corona. Some material falls back to the solar surface and hits the light bridge (i.e., the base of the light wall), then sudden brightenings appear at the wall base followed by the rise of wall top, leading to an increase of the wall height. Once the brightness of the wall base fades, the height of the light wall begins to decrease. Five hours later, another nearby flare takes place, and a bright channel is formed that extends from the flare toward the light bridge. Although no obvious material flow along the bright channel is found, some ejected material is conjectured to reach the light bridge. Subsequently, the wall base brightens and the wall height begins to increase again. Once more, when the brightness of the wall base decays, the wall top fluctuates to lower heights. We suggest, based on the observed cases, that the interaction of falling material and ejected flare material with the light wall results in the brightenings of wall base and causes the height of the light wall to increase. Our results reveal that the light wall can be not only powered by the linkage of p -mode from below the photosphere, but may also be enhanced by external disturbances, such as falling material.

Construction Guide to Next-Generation High-Performance Walls in Climate Zones 3-5 - Part 2: 2x4 Walls

Energy Technology Data Exchange (ETDEWEB)

Kochkin, V. [Home Innovation Research Labs, Upper Marlboro, MD (United States); Wiehagen, J. [Home Innovation Research Labs, Upper Marlboro, MD (United States)

2017-06-01

Part 2 of this Construction Guide to High-Performance Walls in Climate Zones 3-5 provides straightforward and cost-effective strategies to construct durable, energy-efficient walls. It addresses walls constructed with 2x4 wood frame studs, wood structural panel (WSP) sheathing as wall bracing and added backing for foam sheathing, a layer of rigid foam sheathing insulation up to 1.5 inches thick over the WSP, and a cladding system installed over the foam sheathing in low-rise residential buildings up to three stories high. Walls with 2x6 framing are addressed in Part 1 of the Guide.

Construction Guide to Next-Generation High-Performance Walls in Climate Zones 3-5 - Part 2: 2x4 Walls

Energy Technology Data Exchange (ETDEWEB)

Kochkin, V. [Home Innovation Research Labs, Upper Marlboro, MD (United States); Wiehagen, J. [Home Innovation Research Labs, Upper Marlboro, MD (United States)

2017-08-31

Part 2 of this Construction Guide to High-Performance Walls in Climate Zones 3-5 provides straightforward and cost-effective strategies to construct durable, energy-efficient walls. It addresses walls constructed with 2x4 wood frame studs, wood structural panel (WSP) sheathing as wall bracing and added backing for foam sheathing, a layer of rigid foam sheathing insulation up to 1.5 inches thick over the WSP, and a cladding system installed over the foam sheathing in low-rise residential buildings up to three stories high. Walls with 2x6 framing are addressed in Part 1 of the Guide.

Sea Reclamation Status of Countries around the South China Sea from 1975 to 2010

Directory of Open Access Journals (Sweden)

Junjue Zhang

2017-05-01

Full Text Available As a way of turning sea into land for living space for humans, the actions of sea reclamation bring about significant benefits. Nevertheless, it is also an under-recognized threat to the environment and the marine ecosystem. Based on images in two periods, sea reclamation information of countries around the South China Sea was extracted from 1975 to 2010. The spatial state and driven forces of sea reclamation are then discussed. Results show that the overall strength of sea reclamation in the South China Sea was great. New reclaimed land added up to 3264 km2. Sea reclamation for fish farming was the main reclamation type and widely distributed in the whole area, especially on the coast from the Pearl River Delta to the Red River Delta, and the coast of Ca Mau Peninsula. Sea reclamation in China and Vietnam was rather significant, which occupies 80.6% of the total reclamation area. Singapore had the highest level of sea reclamation. New reclaimed land for fish farming holds a key role in China, Vietnam, and Indonesia, while new reclaimed land for construction and docks dominated in Malaysia, Singapore, and Brunei. Areas and use-type compositions of new reclaimed land in countries varied greatly due to the differences of economic factors, policy inclination, and landscapes in the respective countries.

An Investigation of the Radiative Effects and Climate Feedbacks of Sea Ice Sources of Sea Salt Aerosol

Science.gov (United States)

Horowitz, H. M.; Alexander, B.; Bitz, C. M.; Jaegle, L.; Burrows, S. M.

2017-12-01

In polar regions, sea ice is a major source of sea salt aerosol through lofting of saline frost flowers or blowing saline snow from the sea ice surface. Under continued climate warming, an ice-free Arctic in summer with only first-year, more saline sea ice in winter is likely. Previous work has focused on climate impacts in summer from increasing open ocean sea salt aerosol emissions following complete sea ice loss in the Arctic, with conflicting results suggesting no net radiative effect or a negative climate feedback resulting from a strong first aerosol indirect effect. However, the radiative forcing from changes to the sea ice sources of sea salt aerosol in a future, warmer climate has not previously been explored. Understanding how sea ice loss affects the Arctic climate system requires investigating both open-ocean and sea ice sources of sea-salt aerosol and their potential interactions. Here, we implement a blowing snow source of sea salt aerosol into the Community Earth System Model (CESM) dynamically coupled to the latest version of the Los Alamos sea ice model (CICE5). Snow salinity is a key parameter affecting blowing snow sea salt emissions and previous work has assumed constant regional snow salinity over sea ice. We develop a parameterization for dynamic snow salinity in the sea ice model and examine how its spatial and temporal variability impacts the production of sea salt from blowing snow. We evaluate and constrain the snow salinity parameterization using available observations. Present-day coupled CESM-CICE5 simulations of sea salt aerosol concentrations including sea ice sources are evaluated against in situ and satellite (CALIOP) observations in polar regions. We then quantify the present-day radiative forcing from the addition of blowing snow sea salt aerosol with respect to aerosol-radiation and aerosol-cloud interactions. The relative contributions of sea ice vs. open ocean sources of sea salt aerosol to radiative forcing in polar regions is

Seismic Performance of Precast Polystyrene RC Walls

Directory of Open Access Journals (Sweden)

Wibowo Ari

2017-01-01

Full Text Available Precast concrete structure such as precast wall is a concept that is growing rapidly these days. However, the earthquake resistance is believed to be one of its drawbacks. Additionally, the large weight of solid elements also increase the building weight significantly which consequently increase the earthquake base shear force as well. Therefore, investigation on the seismic performance of precast concrete wall has been carried out. Three RC wall specimens using wire mesh reinforcement and EPS (Extended Polystyrene System panel have been tested. This wall was designed as a structural wall that was capable in sustaining lateral loads (in-plane yet were lightweight to reduce the total weight of the building. Parameter observed was the ratio of height to width (aspect ratio of wall of 1.0, 1.5 and 2.0 respectively with the aim to study the behaviour of brittle to ductile transition of the wall. Incremental static load tests were conducted until reaching peak load and then followed by displacement control until failure. Several data were measured at every stage of loading comprising lateral load-displacement behaviour, ultimate strength and collapse mechanism. The outcomes showed that precast concrete walls with a steel wire and EPS panel filler provided considerably good resistance against lateral load.

Sarcocystis neurona infections in sea otter (Enhydra lutris): evidence for natural infections with sarcocysts and transmission of infection to opossums (Didelphis virginiana)

Science.gov (United States)

Dubey, J.P.; Rosypal, A.C.; Rosenthal, B.M.; Thomas, N.J.; Lindsay, D.S.; Stanek, J.F.; Reed, S.M.; Saville, W.J.A.

2001-01-01

Although Sarcocystis neurona has been identified in an array of terrestrial vertebrates, recent recognition of its capacity to infect marine mammals was unexpected. Here, sarcocysts from 2 naturally infected sea otters (Enhydra lutris) were characterized biologically, ultrastructurally, and genetically. DNA was extracted from frozen muscle of the first of these sea otters and was characterized as S. neurona by polymerase chain reation (PCR) amplification followed by restriction fragment length polymorphism analysis and sequencing. Sarcocysts from sea otter no. 1 were up to 350 I?m long, and the villar protrusions on the sarcocyst wall were up to 1.3 I?m long and up to 0.25 I?m wide. The villar protrusions were tapered towards the villar tip. Ultrastructurally, sarcocysts were similar to S. neurona sarcocysts from the muscles of cats experimentally infected with S. neurona sporocysts. Skeletal muscles from a second sea otter failed to support PCR amplification of markers considered diagnostic for S. neurona but did induce the shedding of sporocysts when fed to a laboratory-raised opossum (Didelphis virginiana). Such sporocysts were subsequently fed to knockout mice for the interferon-gamma gene, resulting in infections with an agent identified as S. neurona on the basis of immunohistochemistry, serum antibodies, and diagnostic sequence detection. Thus, sea otters exposed to S. neurona may support the development of mature sarcocysts that are infectious to competent definitive hosts.

Sarcocystis neurona infections in sea otter (Enhydra lutris): evidence for natural infections with sarcocysts and transmission of infection to opossums (Didelphis virginiana).

Science.gov (United States)

Dubey, J R; Rosypal, A C; Rosenthal, B M; Thomas, N J; Lindsay, D S; Stanek, J F; Reed, S M; Saville, W J

2001-12-01

Although Sarcocystis neurona has been identified in an array of terrestrial vertebrates, recent recognition of its capacity to infect marine mammals was unexpected. Here, sarcocysts from 2 naturally infected sea otters (Enhydra lutris) were characterized biologically, ultrastructurally, and genetically. DNA was extracted from frozen muscle of the first of these sea otters and was characterized as S. neurona by polymerase chain reation (PCR) amplification followed by restriction fragment length polymorphism analysis and sequencing. Sarcocysts from sea otter no. 1 were up to 350 microm long, and the villar protrusions on the sarcocyst wall were up to 1.3 microm long and up to 0.25 microm wide. The villar protrusions were tapered towards the villar tip. Ultrastructurally, sarcocysts were similar to S. neurona sarcocysts from the muscles of cats experimentally infected with S. neurona sporocysts. Skeletal muscles from a second sea otter failed to support PCR amplification of markers considered diagnostic for S. neurona but did induce the shedding of sporocysts when fed to a laboratory-raised opossum (Didelphis virginiana). Such sporocysts were subsequently fed to knockout mice for the interferon-gamma gene, resulting in infections with an agent identified as S. neurona on the basis of immunohistochemistry, serum antibodies, and diagnostic sequence detection. Thus, sea otters exposed to S. neurona may support the development of mature sarcocysts that are infectious to competent definitive hosts.

Kinetic wall from Israel

Energy Technology Data Exchange (ETDEWEB)

Godolphin, D.

1985-05-01

An unusual solar mass wall is described. At the turn of a handle it can change from a solar energy collector to a heat-blocker. An appropriate name for it might be the rotating prism wall. An example of the moving wall is at work in an adobe test home in Sede Boqer. Behind a large south-facing window stand four large adobe columns that are triangular in plan. One face of each of them is painted black to absorb sunlight, a second is covered with panels of polystyrene insulation, and a third is painted to match the room decor. These columns can rotate. On winter nights, the insulated side faces the glass, keeping heat losses down. The same scheme works in summer to keep heat out of the house. Small windows provide ventilation.

Measurements of wall shear stress in a planar turbulent Couette flow with porous walls

Science.gov (United States)

Beuther, Paul

2013-11-01

Measurements of drag on a moving web in a multi-span festoon show a stronger than expected dependency on the porosity of the web. The experiments suggest a wall shear stress 3-4 times larger than non-porous webs or historical Couette flow data for solid walls. Previous DNS studies by Jimenez et al. (JFM Vol 442) of boundary layers with passive porous surfaces predict a much smaller increase in wall shear stress for a porous wall of only 40%. Other DNS studies by Quadrio et al. (JFM Vol 576) of porous walls with periodic transpiration do show a large increase in drag under certain periodic conditions of modest amplitude. Although those results are aligned in magnitude with this study, the exact reason for the observed high drag for porous webs in this present study is not understood because there was no external disturbance applied to the web. It can be hypothesized that natural flutter of the web results in a similar mechanism shown in the periodic DNS study, but when the natural flutter was reduced by increasing web tension, there was only a small decrease of the drag. A key difference in this study is that because of the multiple parallel spans in a festoon, any transpiration in one layer must act in the opposite manner on the adjacent span.

High Performance Walls in Hot-Dry Climates

Energy Technology Data Exchange (ETDEWEB)

Hoeschele, Marc [National Renewable Energy Lab. (NREL), Golden, CO (United States); Springer, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dakin, Bill [National Renewable Energy Lab. (NREL), Golden, CO (United States); German, Alea [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-01-01

High performance walls represent a high priority measure for moving the next generation of new homes to the Zero Net Energy performance level. The primary goal in improving wall thermal performance revolves around increasing the wall framing from 2x4 to 2x6, adding more cavity and exterior rigid insulation, achieving insulation installation criteria meeting ENERGY STAR's thermal bypass checklist, and reducing the amount of wood penetrating the wall cavity.

Post wall fixation by lag screw only in associated both column fractures with posterior wall involvement.

Science.gov (United States)

Wang, Hu; Utku, Kandemir; Zhuang, Yan; Zhang, Kun; Fu, Ya-Hui; Wei, Xing; Wang, Peng-Fei; Cong, Yu-Xuan; Lei, Jin-Lai; Zhang, Bin-Fei

2017-07-01

To evaluate the quality of reduction, clinical outcomes and complications of associated both column acetabular fractures with posterior wall involvement that are treated through single ilioinguinal approach and fixation of posterior wall by lag screws only. We conducted a retrospective review involving ninety-nine consecutive patients with associated both column fractures of acetabulum treated through single ilioinguinal approach. Patients were divided into two groups. The first group consisted of 35 patients presented with both column fractures with posterior wall involvement that fixation performed with lag screws. This group was compared to a second group of 64 patients with both column fractures without posterior wall involvement. The quality of reduction was assessed using criteria described by Matta. The size of posterior wall fragment was measured. Functional outcome was evaluated using Modified Postel Merle D'Aubigne score. Radiographs at the latest follow up were analyzed for arthritis (Kellgren-Lawrence classification), and femoral head avascular necrosis (Ficat/Arlet classification). The study showed no significant differences in all preoperative variables (P>0.05). While intraoperative blood loss and operative time in group 1 were increased compared to group 2, the difference was not statistically significant (P>0.05). The height, relative depth and peripheral length of posterior wall respectively were 27.8±2.5mm (range: 24-35mm), 71.5±5.4% (range: 65-88%), 23.0±2.3mm (range: 17-28mm). The mean posterior wall fracture displacement is 5.0±3.2mm (range: 0-11mm). There was no difference regarding the quality of reduction between the two groups (P>0.05). The excellent to good clinical outcome was around 71.4% in the group 1 versus 73.4% in the group 2 at the final follow-up, this difference was not statistically significant (P>0.05). There was no difference in rate of complications between the two groups (P>0.05). Lag screws fixation of posterior wall

Dynamics of plane-symmetric thin walls in general relativity

International Nuclear Information System (INIS)

Wang, A.

1992-01-01

Plane walls (including plane domain walls) without reflection symmetry are studied in the framework of Einstein's general relativity. Using the distribution theory, all the Einstein field equations and Bianchi identities are split into two groups: one holding in the regions outside of the wall and the other holding at the wall. The Einstein field equations at the wall are found to take a very simple form, and given explicitly in terms of the discontinuities of the metric coefficients and their derivatives. The Bianchi identities at the wall are also given explicitly. Using the latter, the interaction of a plane wall with gravitational waves and some specific matter fields is studied. In particular, it is found that, when a gravitational plane wave passes through a wall, if the wall has no reflection symmetry, the phenomena, such as reflection, stimulation, or absorption, in general, occur. It is also found that, unlike for gravitational waves, a massless scalar wave or an electromagnetic wave continuously passes through a wall without any reflection. The repulsion and attraction of a plane wall are also studied. It is found that the acceleration of an observer who is at rest relative to the wall usually consists of three parts: one is due to the force produced by the wall, the second is due to the force produced by the space-time curvature, which is zero if the wall has reflection symmetry, and the last is due to the accelerated motion of the wall. As a result, a repulsive (attractive) plane wall may not be repulsive (attractive) at all. Finally, the collision and interaction among the walls are studied

Desalting of sea water by a wall-less evaporation process; Dessalement de l'eau de mer par un procede d'evaporation sans paroi

Energy Technology Data Exchange (ETDEWEB)

Kassel, C; Sachine, P; Vuillemey, R [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

1966-06-01

The need for fresh water supplies in many parts of the globe has given a great impetus to the study of the desalting of sea-water. Research into this problem has been very varied. Although it is possible in the more-or-less near future that methods based on freezing may be developed, only evaporation methods have industrial applications at the present time. Amongst the many techniques using this method, the most favorably placed installations from the technical and economic points of view are those based on multiple effects and wall-less heat transfer. We have defined the characteristics of a wall-less evaporation process using the various factors involved in this evaporation: energy source, corrosion, furring, heat transfer, maximum temperature, etc... The unit considered in this work has a daily output of 100,000 m{sup 3}, and makes use of the multi-stage technique with an organic heat-carrier. The maximum temperature of the first stage is 150 deg C and the evaporation factor is 0.4. After the description of the process and, the calculation of the equipment, an economic estimate is given of the cost-price : 1.49 F/m{sup 3}. It is likely that more detailed study of the process (technique, equipment and energy consumed) should make it possible to obtain a significant improvement in the process and to reduce the price to 1 F/m{sup 3}. (authors) [French] Le probleme de l 'approvisionnement en eau de nombreuses regions du globe a mis a 1'ordre du jour le dessalement de l'eau de mer. Des recherches sur cette question ont ete faites dans de multiples directions. Si dans un avenir plus ou moins proche les procedes par congelation peuvent se developper, actuellement seules les methodes d'evaporation ont des applications industrielles. Parmi les nombreuses techniques qui visent a mettre en oeuvre ce principe, les installations a multiples effets et transfert de chaleur sans paroi semblent les mieux placees du point de vue technique et economique. A partir des divers

THE CITY- THE PORT-THE SEA The evolutive features of a complex relation

Directory of Open Access Journals (Sweden)

Mario Coletta

2014-01-01

ordinary landscape/town planning tools, or as design interventions for the aesthetic renewal of waterfront building facade. We need to go further, allowing the city to demolish definitely the port barriers which still deprive it of the fruition of its sea, acting consistently with the intervention designed and implemented by Hippodamus of Miletus in Athens during the Age of Pericles, so that the city could join its port (Piraeus, thought with some mediation: a protective wall which would sanction a right of reciprocal belonging, physically and institutionally, between the city and the sea.

OSCILLATING LIGHT WALL ABOVE A SUNSPOT LIGHT BRIDGE

Energy Technology Data Exchange (ETDEWEB)

Yang, Shuhong; Zhang, Jun; Jiang, Fayu [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Xiang, Yongyuan, E-mail: shuhongyang@nao.cas.cn [Fuxian Solar Observatory, Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)

2015-05-10

With the high tempo-spatial Interface Region Imaging Spectrograph 1330 Å images, we find that many bright structures are rooted in the light bridge of NOAA 12192, forming a light wall. The light wall is brighter than the surrounding areas, and the wall top is much brighter than the wall body. The New Vacuum Solar Telescope Hα and the Solar Dynamics Observatory 171 and 131 Å images are also used to study the light-wall properties. In 1330, 171, and 131 Å, the top of the wall has a higher emission, while in the Hα line, the wall-top emission is very low. The wall body corresponds to bright areas in 1330 Å and dark areas in the other lines. The top of the light wall moves upward and downward successively, performing oscillations in height. The deprojected mean height, amplitude, oscillation velocity, and the dominant period are determined to be 3.6 Mm, 0.9 Mm, 15.4 km s{sup −1}, and 3.9 minutes, respectively. We interpret the oscillations of the light wall as the leakage of p-modes from below the photosphere. The constant brightness enhancement of the wall top implies the existence of some kind of atmospheric heating, e.g., via the persistent small-scale reconnection or the magneto-acoustic waves. In another series of 1330 Å images, we find that the wall top in the upward motion phase is significantly brighter than in the downward phase. This kind of oscillation may be powered by the energy released due to intermittent impulsive magnetic reconnection.

Evaluation of cell wall preparations for proteomics: a new procedure for purifying cell walls from Arabidopsis hypocotyls

Directory of Open Access Journals (Sweden)

Canut Hervé

2006-05-01

Full Text Available Abstract Background The ultimate goal of proteomic analysis of a cell compartment should be the exhaustive identification of resident proteins; excluding proteins from other cell compartments. Reaching such a goal closely depends on the reliability of the isolation procedure for the cell compartment of interest. Plant cell walls possess specific difficulties: (i the lack of a surrounding membrane may result in the loss of cell wall proteins (CWP during the isolation procedure, (ii polysaccharide networks of cellulose, hemicelluloses and pectins form potential traps for contaminants such as intracellular proteins. Several reported procedures to isolate cell walls for proteomic analyses led to the isolation of a high proportion (more than 50% of predicted intracellular proteins. Since isolated cell walls should hold secreted proteins, one can imagine alternative procedures to prepare cell walls containing a lower proportion of contaminant proteins. Results The rationales of several published procedures to isolate cell walls for proteomics were analyzed, with regard to the bioinformatic-predicted subcellular localization of the identified proteins. Critical steps were revealed: (i homogenization in low ionic strength acid buffer to retain CWP, (ii purification through increasing density cushions, (iii extensive washes with a low ionic strength acid buffer to retain CWP while removing as many cytosolic proteins as possible, and (iv absence of detergents. A new procedure was developed to prepare cell walls from etiolated hypocotyls of Arabidopsis thaliana. After salt extraction, a high proportion of proteins predicted to be secreted was released (73%, belonging to the same functional classes as proteins identified using previously described protocols. Finally, removal of intracellular proteins was obtained using detergents, but their amount represented less than 3% in mass of the total protein extract, based on protein quantification. Conclusion The

Control of Wall Mounting Robot

DEFF Research Database (Denmark)

Sloth, Christoffer; Pedersen, Rasmus

2017-01-01

This paper presents a method for designing controllers for trajectory tracking with actuator constraints. In particular, we consider a joystick-controlled wall mounting robot called WallMo. In contrast to previous works, a model-free approach is taken to the control problem, where the path...

Moisture Research - Optimizing Wall Assemblies

Energy Technology Data Exchange (ETDEWEB)

Arena, L.; Mantha, P.

2013-05-01

The Consortium for Advanced Residential Buildings (CARB) evaluated several different configurations of wall assemblies to determine the accuracy of moisture modeling and make recommendations to ensure durable, efficient assemblies. WUFI and THERM were used to model the hygrothermal and heat transfer characteristics of these walls.

Arctic Sea Level Reconstruction

DEFF Research Database (Denmark)

Svendsen, Peter Limkilde

Reconstruction of historical Arctic sea level is very difficult due to the limited coverage and quality of tide gauge and altimetry data in the area. This thesis addresses many of these issues, and discusses strategies to help achieve a stable and plausible reconstruction of Arctic sea level from...... 1950 to today.The primary record of historical sea level, on the order of several decades to a few centuries, is tide gauges. Tide gauge records from around the world are collected in the Permanent Service for Mean Sea Level (PSMSL) database, and includes data along the Arctic coasts. A reasonable...... amount of data is available along the Norwegian and Russian coasts since 1950, and most published research on Arctic sea level extends cautiously from these areas. Very little tide gauge data is available elsewhere in the Arctic, and records of a length of several decades,as generally recommended for sea...

Putting SEA in context: A discourse perspective on how SEA contributes to decision-making

International Nuclear Information System (INIS)

Runhaar, Hens

2009-01-01

Over the last couple of years there is an ongoing debate in the environmental assessment literature about the contribution of Strategic Environmental Assessment (SEA) to public decision-making and how this can be understood and enhanced by better incorporating insights from policy analysis, planning theory and political sciences. By explicitly framing SEA as an element in a process where stakeholders with diverging interests struggle, acceptability of SEA processes and results by stakeholders has become an important element in SEA evaluation. In addition, the importance of other context variables, such as the institutional organisation, and the need for SEA to adapt to this context, is stressed. Thus far, publications in this area have been dealing with the operationalisation of SEA's 'contribution', typologies of roles that SEA can or should play in different policy settings and on factors that stimulate or impede SEA to play these roles. In this paper an alternative approach is suggested that starts from the deliberative processes around a particular policy issue or decision supported by SEA. Of particular interest are 'discourses': the frames through which groups of actors give meaning to aspects of the policy issues and decisions that are supported by SEA. Discourses do not only reflect conflicts of interests and power play, but also the ways in which actors perceive and understand aspects of the world. Decision-making is conceptualised as a 'system of competing discourse coalitions and their struggles to 'control shared meanings' and to gain acceptance of their framing of a policy issue' [Durning D. A review of Fischer and Forrester (1993) The argumentative turn in policy analysis and planning. Policy Sci 1995;28(1):102-8]. SEA is one of the events in this process that may impact upon dominant discourses. Discourse analysis allows for an understanding of arguments that are considered legitimate for (not) incorporating particular elements of SEA. In addition it

Sea-ice thickness from field measurements in the northwestern Barents Sea

Science.gov (United States)

King, Jennifer; Spreen, Gunnar; Gerland, Sebastian; Haas, Christian; Hendricks, Stefan; Kaleschke, Lars; Wang, Caixin

2017-02-01

The Barents Sea is one of the fastest changing regions of the Arctic, and has experienced the strongest decline in winter-time sea-ice area in the Arctic, at -23±4% decade-1. Sea-ice thickness in the Barents Sea is not well studied. We present two previously unpublished helicopter-borne electromagnetic (HEM) ice thickness measurements from the northwestern Barents Sea acquired in March 2003 and 2014. The HEM data are compared to ice thickness calculated from ice draft measured by ULS deployed between 1994 and 1996. These data show that ice thickness varies greatly from year to year; influenced by the thermodynamic and dynamic processes that govern local formation vs long-range advection. In a year with a large inflow of sea-ice from the Arctic Basin, the Barents Sea ice cover is dominated by thick multiyear ice; as was the case in 2003 and 1995. In a year with an ice cover that was mainly grown in situ, the ice will be thin and mechanically unstable; as was the case in 2014. The HEM data allow us to explore the spatial and temporal variability in ice thickness. In 2003 the dominant ice class was more than 2 years old; and modal sea-ice thickness varied regionally from 0.6 to 1.4 m, with the thinner ice being either first-year ice, or multiyear ice which had come into contact with warm Atlantic water. In 2014 the ice cover was predominantly locally grown ice less than 1 month old (regional modes of 0.5-0.8 m). These two situations represent two extremes of a range of possible ice thickness distributions that can present very different conditions for shipping traffic; or have a different impact on heat transport from ocean to atmosphere.

Modeling of shear wall buildings

Energy Technology Data Exchange (ETDEWEB)

Gupta, A K [North Carolina State Univ., Raleigh (USA). Dept. of Civil Engineering

1984-05-01

Many nuclear power plant buildings, for example, the auxiliary building, have reinforced concrete shear walls as the primary lateral load resisting system. Typically, these walls have low height to length ratio, often less than unity. Such walls exhibit marked shear lag phenomenon which would affect their bending stiffness and the overall stress distribution in the building. The deformation and the stress distribution in walls have been studied which is applicable to both the short and the tall buildings. The behavior of the wall is divided into two parts: the symmetric flange action and the antisymmetry web action. The latter has two parts: the web shear and the web bending. Appropriate stiffness equations have been derived for all the three actions. These actions can be synthesized to solve any nonlinear cross-section. Two specific problems, that of lateral and torsional loadings of a rectangular box, have been studied. It is found that in short buildings shear lag plays a very important role. Any beam type formulation which either ignores shear lag or includes it in an idealized form is likely to lead to erroneous results. On the other hand a rigidity type approach with some modifications to the standard procedures would yield nearly accurate answers.

Timber frame walls

DEFF Research Database (Denmark)

Hansen, Ernst Jan de Place; Brandt, Erik

2010-01-01

A ventilated cavity is usually considered good practice for removing moisture behind the cladding of timber framed walls. Timber frame walls with no cavity are a logical alternative as they are slimmer and less expensive to produce and besides the risk of a two-sided fire behind the cladding....... It was found that the specific damages made to the vapour barrier as part of the test did not have any provable effect on the moisture content. In general elements with an intact vapour barrier did not show a critical moisture content at the wind barrier after four years of exposure....

From Soft Walls to Infrared Branes

CERN Document Server

von Gersdorff, Gero

2010-01-01

Five dimensional warped spaces with soft walls are generalizations of the standard Randall-Sundrum compactifications, where instead of an infrared brane one has a curvature singularity (with vanishing warp factor) at finite proper distance in the bulk. We project the physics near the singularity onto a hypersurface located a small distance away from it in the bulk. This results in a completely equivalent description of the soft wall in terms of an effective infrared brane, hiding any singular point. We perform explicitly this calculation for two classes of soft wall backgrounds used in the literature. The procedure has several advantages. It separates in a clean way the physics of the soft wall from the physics of the five dimensional bulk, facilitating a more direct comparison with standard two-brane warped compactifications. Moreover, consistent soft walls show a sort of universal behavior near the singularity which is reflected in the effective brane Lagrangian. Thirdly, for many purposes, a good approxima...

Experimental investigation on particle-wall interactions

International Nuclear Information System (INIS)

Zeisel, H.; Dorfner, V.

1988-01-01

There is still a lack in the knowledge about many physical processes in two-phase flows and therefore their mathematical description for the modelling of two-phase flows by computer simulations still needs some improvement. One required information is the physical procedure of the momentum transfer between the phases themselves, such as particle-particle or particle-fluid interactions, and between the phases and the flow boundaries, such as particle-wall or fluid-wall interactions. The interaction between the two phases can be either a 'long-range' interference or a direct contact between both. For the particle-fluid two-phase flow system the interaction can be devided in particle-fluid, particle-particle and particle-boundary interactions. In this investigation the attention is drawn to the special case of a particle-wall interaction and its 'long-range' interference effect between the wall and a small particle which approaches the wall in normal direction. (orig./GL)

SeaRAM: an evaluation of the safety of RAM transport by sea

International Nuclear Information System (INIS)

McConnell, P.; Sorenson, K.B.; Carter, M.H.; Keane, M.P.; Keith, V.F.; Heid, R.J.

1995-01-01

SeaRAM is a multi-year Department of Energy (DOE) project designed to validate the safety of shipping radioactive materials (RAM) by sea. The project has an ultimate goal of developing and demonstrating analytic tools for performing comprehensive analyses to evaluate the risks to humans and the environment due to sea transport of plutonium, vitrified high-level waste (VHLW), and spent fuel associated with reprocessing and research reactors. To achieve this end, evaluations of maritime databases and structural an thermal analyses of particular severe collision and fire accidents have been and will continue to be conducted. Program management for SeaRAM is based at the DOE's Office of Environmental Restoration. Technical activities for the project are being conducted at Sandia National Laboratories (SNL). Several private organizations are also involved in providing technical support, notably Engineering Computer Optecnomics, Inc. (ECO). The technical work performed for SeaRAM also supports DOE participation in an International Atomic Energy Agency (IAEA) Cooperative Research Program (CRP) entitled Accident Severity at Sea During Transport of Radioactive Material. This paper discusses activities performed during the first year of the project

Effects of dietary n-3 highly unsaturated fatty acids (HUFAs) on growth, fatty acid profiles, antioxidant capacity and immunity of sea cucumber Apostichopus japonicus (Selenka).

Science.gov (United States)

Yu, Haibo; Gao, Qinfeng; Dong, Shuanglin; Zhou, Jishu; Ye, Zhi; Lan, Ying

2016-07-01

The present study was conducted to understand the effects of dietary n-3 highly unsaturated fatty acids (HUFAs) on growth, fatty acid profiles, antioxidant capacity and the immunity of sea cucumber Apostichopus japonicus (Selenka). Five experimental diets were prepared, containing graded levels of n-3 HUFAs (0.46%, 0.85%, 1.25%, 1.61% and 1.95%, respectively), and the 0.46% group was used as control group. The specific growth rates, fatty acid profiles, activities and gene expression of antioxidative enzymes and lysozyme of the sea cucumbers that were fed with the 5 experimental diets were determined. The results showed that the specific growth rate of sea cucumbers in all the treatment groups significantly increased compared to the control group (P sea cucumbers. The contents of eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) in the body wall of the sea cucumbers gradually increased with the increasing levels of n-3 HUFAs in the diets. The suitable supplement of n-3 HUFAs in diets improved the activities of superoxide dismutase (SOD) and catalase (CAT) of sea cucumbers by up-regulating the expression of SOD and CAT mRNA in sea cucumbers. However, excess n-3 HUFAs in diets caused lipid peroxidation, inhibited the expression of lysozyme (LSZ) mRNA and decreased the activities of LSZ in sea cucumbers. In summary, the suitable supplement levels of n-3 HUFAs in diets of sea cucumbers A. japonicus were estimated between 0.85% and 1.25% considering the growth performance, cost and the indicators of antioxidant capacity and immunity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sea level ~400 000 years ago (MIS 11: analogue for present and future sea-level?

Directory of Open Access Journals (Sweden)

D. Q. Bowen

2010-01-01

Full Text Available Comparison of the sea-level today with that of 400 000 years ago (MIS 11, when the Earth's orbital characteristics were similar may provide, under conditions of natural variability, indications of future sea-level during the present interglacial. Then, as now, orbital eccentricity was low and precession dampened. Evidence for MIS 11 sea-level occurs on uplifting coastlines where shorelines with geochronological ages have been preserved. The sea-level term and the uplift term may be separated with an "uplift correction" formula. This discovers the original sea-level at which the now uplifted shoreline was fashioned. Estimates are based on average uplift rates of the "last interglacial" sea-level (MIS 5.5 using a range of estimates for sea-level and age at that time at different locations. These, with varying secular tectonic regimes in different ocean basins, provide a band of estimates for the MIS 11 sea-level. They do not support the hypothesis of an MIS 11 sea-level at ~20 m, and instead show that it was closer to its present level.

Moisture Management for High R-Value Walls

Energy Technology Data Exchange (ETDEWEB)

Lepage, R.; Schumacher, C.; Lukachko, A.

2013-11-01

The following report explains the moisture-related concerns for High R-value wall assemblies and discusses past Building America research work that informs this study. Hygrothermal simulations were prepared for several common approaches to High R-value wall construction in six cities (Houston, Atlanta, Seattle, St. Louis, Chicago, and International Falls) representing a range of climate zones (2, 3, 4C, 4, 5A, and 7, respectively). The simulations are informed by experience gained from past research in this area and validated by field measurement and forensic experience. The modeling program was developed to assess the moisture durability of the wall assemblies based on three primary sources of moisture: construction moisture, air leakage condensation, and bulk water leakage. The peak annual moisture content of the wood based exterior sheathing was used to comparatively analyze the response to the moisture loads for each of the walls in each given city. Walls which experienced sheathing moisture contents between 20% and 28% were identified as risky, whereas those exceeding 28% were identified as very high risk. All of the wall assemblies perform well under idealized conditions. However, only the walls with exterior insulation, or cavity insulation which provides a hygrothermal function similar to exterior insulation, perform adequately when exposed to moisture loads. Walls with only cavity insulation are particularly susceptible to air leakage condensation. None of the walls performed well when a precipitation based bulk water leak was introduced to the backside of the sheathing, emphasizing the importance of proper flashing details.

Hygrothermal behavior for a clay brick wall

Science.gov (United States)

Allam, R.; Issaadi, N.; Belarbi, R.; El-Meligy, M.; Altahrany, A.

2018-06-01

In Egypt, the clay brick is the common building materials which are used. By studying clay brick walls behavior for the heat and moisture transfer, the efficient use of the clay brick can be reached. So, this research studies the hygrothermal transfer in this material by measuring the hygrothermal properties and performing experimental tests for a constructed clay brick wall. We present the model for the hygrothermal transfer in the clay brick which takes the temperature and the vapor pressure as driving potentials. In addition, this research compares the presented model with previous models. By constructing the clay brick wall between two climates chambers with different boundary conditions, we can validate the numerical model and analyze the hygrothermal transfer in the wall. The temperature and relative humidity profiles within the material are measured experimentally and determined numerically. The numerical and experimental results have a good convergence with 3.5% difference. The surface boundary conditions, the ground effect, the infiltration from the closed chambers and the material heterogeneity affects the results. Thermal transfer of the clay brick walls reaches the steady state very rapidly than the moisture transfer. That means the effect of using only the external brick wall in the building in hot climate without increase the thermal resistance for the wall, will add more energy losses in the clay brick walls buildings. Also, the behavior of the wall at the heat and mass transfer calls the three-dimensional analysis for the whole building to reach the real behavior.

Hygrothermal behavior for a clay brick wall

Science.gov (United States)

Allam, R.; Issaadi, N.; Belarbi, R.; El-Meligy, M.; Altahrany, A.

2018-01-01

In Egypt, the clay brick is the common building materials which are used. By studying clay brick walls behavior for the heat and moisture transfer, the efficient use of the clay brick can be reached. So, this research studies the hygrothermal transfer in this material by measuring the hygrothermal properties and performing experimental tests for a constructed clay brick wall. We present the model for the hygrothermal transfer in the clay brick which takes the temperature and the vapor pressure as driving potentials. In addition, this research compares the presented model with previous models. By constructing the clay brick wall between two climates chambers with different boundary conditions, we can validate the numerical model and analyze the hygrothermal transfer in the wall. The temperature and relative humidity profiles within the material are measured experimentally and determined numerically. The numerical and experimental results have a good convergence with 3.5% difference. The surface boundary conditions, the ground effect, the infiltration from the closed chambers and the material heterogeneity affects the results. Thermal transfer of the clay brick walls reaches the steady state very rapidly than the moisture transfer. That means the effect of using only the external brick wall in the building in hot climate without increase the thermal resistance for the wall, will add more energy losses in the clay brick walls buildings. Also, the behavior of the wall at the heat and mass transfer calls the three-dimensional analysis for the whole building to reach the real behavior.

The radioactivity of the sea

International Nuclear Information System (INIS)

Walker, M.I.; Rose, K.S.B.

1990-01-01

The radioactivity in the world's surface sea water averages 13.6 Bq/kg of water. Over 88% of this activity arises from a single natural radionuclide, 40 K, and 7% of the remainder results from nuclear weapon test fallout. Variations in the radioactivity occur due to changes in salinity, weapon test fallout and discharges of artificial radionuclides, and are examined here on the basis of published measurements. The most radioactive sea identified by these measurements is the Dead Sea, which averages 178 Bq/kg due to its high salinity. Other enclosed, highly saline waters can be expected to have similar levels. The radioactivity in open seas varies within a much narrower range, generally within 20% of the world average. The highest averages are found in the Persian Gulf (22 Bq/kg), the Red Sea (15 Bq/kg) and the Eastern Mediterranean (14.6 Bq/kg). The Irish Sea averaged 13.7 Bq/kg in 1987, with the effect of the Sellafield discharges being partly offset by lower than average salinity. Although higher levels occurred in the Irish Sea during the 1970s when the Sellafield discharges were higher, the average level has always been much less than that in the Dead Sea, so that the Irish Sea has never been the most radioactive sea in the world. Exceptionally low levels of radioactivity (4 Bq/kg) occur in the Baltic Sea due to dilution by fresh water. (author)

Functional duality of the cell wall.

Science.gov (United States)

Latgé, Jean-Paul; Beauvais, Anne

2014-08-01

The polysaccharide cell wall is the extracellular armour of the fungal cell. Although essential in the protection of the fungal cell against aggressive external stresses, the biosynthesis of the polysaccharide core is poorly understood. For a long time it was considered that this cell wall skeleton was a fixed structure whose role was only to be sensed as non-self by the host and consequently trigger the defence response. It is now known that the cell wall polysaccharide composition and localization continuously change to adapt to their environment and that these modifications help the fungus to escape from the immune system. Moreover, cell wall polysaccharides could function as true virulence factors. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chronic Abdominal Wall Pain.

Science.gov (United States)

Koop, Herbert; Koprdova, Simona; Schürmann, Christine

2016-01-29

Chronic abdominal wall pain is a poorly recognized clinical problem despite being an important element in the differential diagnosis of abdominal pain. This review is based on pertinent articles that were retrieved by a selective search in PubMed and EMBASE employing the terms "abdominal wall pain" and "cutaneous nerve entrapment syndrome," as well as on the authors' clinical experience. In 2% to 3% of patients with chronic abdominal pain, the pain arises from the abdominal wall; in patients with previously diagnosed chronic abdominal pain who have no demonstrable pathological abnormality, this likelihood can rise as high as 30% . There have only been a small number of clinical trials of treatment for this condition. The diagnosis is made on clinical grounds, with the aid of Carnett's test. The characteristic clinical feature is strictly localized pain in the anterior abdominal wall, which is often mischaracterized as a "functional" complaint. In one study, injection of local anesthesia combined with steroids into the painful area was found to relieve pain for 4 weeks in 95% of patients. The injection of lidocaine alone brought about improvement in 83-91% of patients. Long-term pain relief ensued after a single lidocaine injection in 20-30% of patients, after repeated injections in 40-50% , and after combined lidocaine and steroid injections in up to 80% . Pain that persists despite these treatments can be treated with surgery (neurectomy). Chronic abdominal wall pain is easily diagnosed on physical examination and can often be rapidly treated. Any physician treating patients with abdominal pain should be aware of this condition. Further comparative treatment trials will be needed before a validated treatment algorithm can be established.

Soft impact testing of a wall-floor-wall reinforced concrete structure

Energy Technology Data Exchange (ETDEWEB)

Vepsä, Ari, E-mail: ari.vepsa@vtt.fi; Calonius, Kim; Saarenheimo, Arja; Aatola, Seppo; Halonen, Matti

2017-01-15

Highlights: • A wall-floor-wall reinforced concrete structure was built. • The structure was subjected to three almost identical soft impact tests. • Response was measured with accelerometers, displacement sensors and strain gauges. • Modal tests was also carried out with the same structure in different conditions. • The results are meant to be used for validation of computational methods and models. - Abstract: Assessing the safety of the reactor building of a nuclear power plant against the crash of an airplane calls for valid computational tools such as finite element models and material constitutive models. Validation of such tools and models in turn calls for reliable and relevant experimental data. The problem is that such data is scarcely available. One of the aspects of such a crash is vibrations that are generated by the impact. These vibrations tend to propagate from the impact point to the internal parts of the building. If strong enough, these vibrations may cause malfunction of the safety-critical equipment inside the building. To enable validation of computational models for this type of behaviour, we have conducted a series of three tests with a wall-floor-wall reinforced concrete structure under soft impact loading. The response of the structure was measured with accelerometers, displacement sensors and strain gauges. In addition to impact tests, the structure was subjected to modal tests under different conditions. The tests yielded a wealth of useful data for validation of computational models and better understanding about shock induced vibration physics especially in reinforced concrete structures.

Potential of sea level rise impact on South China Sea: a preliminary ...

African Journals Online (AJOL)

The effect of the sea level rise was involved the existence of sea water intrusion and coastal erosion phenomenon in the coastal of Terengganu. This study aim to determine fluctuation of high and low tides of the South China Sea in their relation to water quality value of Marang and Paka Rivers as well as from wells ...

Formation and spreading of Red Sea Outflow Water in the Red Sea

Science.gov (United States)

Zhai, Ping; Bower, Amy S.; Smethie, William M.; Pratt, Larry J.

2015-09-01

Hydrographic data, chlorofluorocarbon-12 (CFC-12) and sulfur hexafluoride (SF6) measurements collected in March 2010 and September-October 2011 in the Red Sea, as well as an idealized numerical experiment are used to study the formation and spreading of Red Sea Outflow Water (RSOW) in the Red Sea. Analysis of inert tracers, potential vorticity distributions, and model results confirm that RSOW is formed through mixed-layer deepening caused by sea surface buoyancy loss in winter in the northern Red Sea and reveal more details on RSOW spreading rates, pathways, and vertical structure. The southward spreading of RSOW after its formation is identified as a layer with minimum potential vorticity and maximum CFC-12 and SF6. Ventilation ages of seawater within the RSOW layer, calculated from the partial pressure of SF6 (pSF6), range from 2 years in the northern Red Sea to 15 years at 17°N. The distribution of the tracer ages is in agreement with the model circulation field which shows a rapid transport of RSOW from its formation region to the southern Red Sea where there are longer circulation pathways and hence longer residence time due to basin wide eddies. The mean residence time of RSOW within the Red Sea estimated from the pSF6 age is 4.7 years. This time scale is very close to the mean transit time (4.8 years) for particles from the RSOW formation region to reach the exit at the Strait of Bab el Mandeb in the numerical experiment.

Formation of Barents Sea Branch Water in the north-eastern Barents Sea

Directory of Open Access Journals (Sweden)

Vidar S. Lien

2013-09-01

Full Text Available The Barents Sea throughflow accounts for approximately half of the Atlantic Water advection to the Arctic Ocean, while the other half flows through Fram Strait. Within the Barents Sea, the Atlantic Water undergoes considerable modifications before entering the Arctic Ocean through the St. Anna Trough. While the inflow area in the south-western Barents Sea is regularly monitored, oceanographic data from the outflow area to the north-east are very scarce. Here, we use conductivity, temperature and depth data from August/September 2008 to describe in detail the water masses present in the downstream area of the Barents Sea, their spatial distribution and transformations. Both Cold Deep Water, formed locally through winter convection and ice-freezing processes, and Atlantic Water, modified mainly through atmospheric cooling, contribute directly to the Barents Sea Branch Water. As a consequence, it consists of a dense core characterized by a temperature and salinity maximum associated with the Atlantic Water, in addition to the colder, less saline and less dense core commonly referred to as the Barents Sea Branch Water core. The denser core likely constitutes a substantial part of the total flow, and it is more saline and considerably denser than the Fram Strait branch as observed within the St. Anna Trough. Despite the recent warming of the Barents Sea, the Barents Sea Branch Water is denser than observed in the 1990s, and the bottom water observed in the St. Anna Trough matches the potential density at 2000 m depth in the Arctic Ocean.

Sea ice contribution to the air-sea CO{sub 2} exchange in the Arctic and Southern Oceans

Energy Technology Data Exchange (ETDEWEB)

Rysgaard, Soeren (Greenland Climate Research Centre, Greenland Inst. of Natural Resources, Nuuk, Greenland (Denmark); Centre for Earth Observation Science, CHR Faculty of Environment Earth and Resources, Univ. of Manitoba, Winnipeg (Canada)), e-mail: rysgaard@natur.gl; Bendtsen, Joergen (Greenland Climate Research Centre, Greenland Inst. of Natural Resources, Nuuk, Greenland (Denmark); Centre for Ice and Climate, Niels Bohr Inst., Univ. of Copenhagen, Copenhagen O (Denmark)); Delille, Bruno (Unit' e d' Oceanographie Chimique, Interfacultary Centre for Marine Research, Universite de Liege, Liege (Belgium)); Dieckmann, Gerhard S. (Alfred Wegener Inst. for Polar and Marine Research, Bremerhaven (Germany)); Glud, Ronnie N. (Greenland Climate Research Centre, Greenland Inst. of Natural Resources, Nuuk, Greenland (Denmark); Scottish Association of Marine Sciences, Scotland UK, Southern Danish Univ. and NordCee, Odense M (Denmark)); Kennedy, Hilary; Papadimitriou, Stathys (School of Ocean Sciences, Bangor Univ., Menai Bridge, Anglesey, Wales (United Kingdom)); Mortensen, John (Greenland Climate Research Centre, Greenland Inst. of Natural Resources, Nuuk, Greenland (Denmark)); Thomas, David N. (School of Ocean Sciences, Bangor Univ., Menai Bridge, Anglesey, Wales (United Kingdom); Finnish Environment Inst. (SYKE), Marine Research Centre, Helsinki (Finland)); Tison, Jean-Louis (Glaciology Unit, Dept. of Earth and Environmental Sciences, Universite Libre de Bruxelles, Bruxelles, (Belgium))

2011-11-15

Although salt rejection from sea ice is a key process in deep-water formation in ice-covered seas, the concurrent rejection of CO{sub 2} and the subsequent effect on air-sea CO{sub 2} exchange have received little attention. We review the mechanisms by which sea ice directly and indirectly controls the air-sea CO{sub 2} exchange and use recent measurements of inorganic carbon compounds in bulk sea ice to estimate that oceanic CO{sub 2} uptake during the seasonal cycle of sea-ice growth and decay in ice-covered oceanic regions equals almost half of the net atmospheric CO{sub 2} uptake in ice-free polar seas. This sea-ice driven CO{sub 2} uptake has not been considered so far in estimates of global oceanic CO{sub 2} uptake. Net CO{sub 2} uptake in sea-ice-covered oceans can be driven by; (1) rejection during sea-ice formation and sinking of CO{sub 2}-rich brine into intermediate and abyssal oceanic water masses, (2) blocking of air-sea CO{sub 2} exchange during winter, and (3) release of CO{sub 2}-depleted melt water with excess total alkalinity during sea-ice decay and (4) biological CO{sub 2} drawdown during primary production in sea ice and surface oceanic waters

The Red Sea during the Last Glacial Maximum: implications for sea level reconstructions

Science.gov (United States)

Gildor, H.; Biton, E.; Peltier, W. R.

2006-12-01

The Red Sea (RS) is a semi-enclosed basin connected to the Indian Ocean via a narrow and shallow strait, and surrounded by arid areas which exhibits high sensitivity to atmospheric changes and sea level reduction. We have used the MIT GCM to investigate the changes in the hydrography and circulation in the RS in response to reduced sea level, variability in the Indian monsoons, and changes in atmospheric temperature and humidity that occurred during the Last Glacial Maximum (LGM). The model results show high sensitivity to sea level reduction especially in the salinity field (increasing with the reduction in sea level) together with a mild atmospheric impact. Sea level reduction decreases the stratification, increases subsurface temperatures, and alters the circulation pattern at the Strait of Bab el Mandab, which experiences a transition from submaximal flow to maximal flow. The reduction in sea level at LGM alters the location of deep water formation which shifts to an open sea convective site in the northern part of the RS compared to present day situation in which deep water is formed from the Gulf of Suez outflow. Our main result based on both the GCM and on a simple hydraulic control model which takes into account mixing process at the Strait of Bab El Mandeb, is that sea level was reduced by only ~100 m in the Bab El Mandeb region during the LGM, i.e. the water depth at the Hanish sill (the shallowest part in the Strait Bab el Mandab) was around 34 m. This result agrees with the recent reconstruction of the LGM low stand of the sea in this region based upon the ICE-5G (VM2) model of Peltier (2004).

Ballistic Limit Equation for Single Wall Titanium

Science.gov (United States)

Ratliff, J. M.; Christiansen, Eric L.; Bryant, C.

2009-01-01

Hypervelocity impact tests and hydrocode simulations were used to determine the ballistic limit equation (BLE) for perforation of a titanium wall, as a function of wall thickness. Two titanium alloys were considered, and separate BLEs were derived for each. Tested wall thicknesses ranged from 0.5mm to 2.0mm. The single-wall damage equation of Cour-Palais [ref. 1] was used to analyze the Ti wall's shielding effectiveness. It was concluded that the Cour-Palais single-wall equation produced a non-conservative prediction of the ballistic limit for the Ti shield. The inaccurate prediction was not a particularly surprising result; the Cour-Palais single-wall BLE contains shield material properties as parameters, but it was formulated only from tests of different aluminum alloys. Single-wall Ti shield tests were run (thicknesses of 2.0 mm, 1.5 mm, 1.0 mm, and 0.5 mm) on Ti 15-3-3-3 material custom cut from rod stock. Hypervelocity impact (HVI) tests were used to establish the failure threshold empirically, using the additional constraint that the damage scales with impact energy, as was indicated by hydrocode simulations. The criterion for shield failure was defined as no detached spall from the shield back surface during HVI. Based on the test results, which confirmed an approximately energy-dependent shield effectiveness, the Cour-Palais equation was modified.

Morphological beak differences of loliginid squid, Uroteuthis chinensis and Uroteuthis edulis, in the northern South China Sea

Science.gov (United States)

Jin, Yue; Liu, Bilin; Chen, Xinjun; Staples, Kevin

2018-03-01

The mitre squid ( Uroteuthis chinensis) and the swordtip squid ( U. edulis) are Indo-Pacific cephalopod species that are abundant in the western Pacific Ocean. They are currently exploited in the East and South China Seas and make up a significant portion of the Chinese neritic squid catch. Beaks, the feeding organs of squid, are important for individual size and biomass estimation because of their high resistance to degradation in predator stomachs and consistent dimensions. In this study, 104 U. chinensis and 143 U. edulis individuals were sampled from northern South China Sea with mantle length from 70 to 260 mm and 96 to 284 mm, respectively. The results indicated that morphological beak values were greater for U. edulis, compared to U. chinensis, for upper hood length (UHL), upper crest length (UCL), upper lateral wall length (ULWL), lower crest length (LCL), and lower lateral wall length (LLWL). According to principal component analysis, UHL/ML, UCL/ML, ULWL/ML, LCL/ML, LLWL/ML and LWL/ML could represent the characteristics of beaks for U. chinensis, while UHL/ML, UCL/ML, ULWL/ML, LHL/ML, LCL/ML and LLWL/ML could represent it for U. edulis. According to Akaike's information criterion (AIC) values, a power function was the most suitable model for U. chinensis, while a linear function was the most suitable model for U. edulis. The beak variable-mantle length ratio (beak variable/mantle length) declined with the increasing of mantle length and declined sharply at the early stage of growth in both beaks and species. The ratio changed quickly after achieving the mantle length of 140 mm for U. chinensis, while the ratio changed quickly after 170 mm for U. edulis. Beaks in both species experienced sharper changes through maturity stage I to II than other maturity stages. This study gives us basic beak morphology information for U. chinensis and U. edulis in the East and South China Seas. Geometric morphological methods combined with dietary analysis should be used

Intermittency and scaling laws for wall bounded turbulence

OpenAIRE

Benzi, R.; Amati, G.; Casciola, C. M.; Toschi, F.; Piva, R.

1998-01-01

Well defined scaling laws clearly appear in wall bounded turbulence, even very close to the wall, where a distinct violation of the refined Kolmogorov similarity hypothesis (RKSH) occurs together with the simultaneous persistence of scaling laws. A new form of RKSH for the wall region is here proposed in terms of the structure functions of order two which, in physical terms, confirms the prevailing role of the momentum transfer towards the wall in the near wall dynamics.

Active compliant wall for skin friction reduction

International Nuclear Information System (INIS)

Pätzold, A.; Peltzer, I.; Nitsche, W.; Goldin, N.; King, R.; Haller, D.; Woias, P.

2013-01-01

Highlights: • Objective: Delay of laminar-turbulent transition on a wing by active wall actuation. • Natural, convective TS-instabilities are damped by travelling counter waves. • Piezo driven active wall and model predictive controller were developed. • TS amplitudes were damped by 83.6% (equals 15.7 dB within instability band). • Significant effect on skin friction distribution. -- Abstract: In order to reduce skin friction drag, an active laminarisation method is developed. Laminar-turbulent boundary layer transition caused by Tollmien–Schlichting (TS) waves is delayed by attenuation of these convective instabilities. An actively driven compliant wall is integrated as part of a wing’s surface. Different configurations of piezo-based actuators are combined with an array of sensitive surface flow sensors. Wall-normal actuation as well as inclined wall displacement are investigated. Together with a realtime-control strategy, transition onset is shifted downstream by six average TS-wave lengths. Using the example of flow velocity, the influence of variable flow conditions on TS-damping rates was investigated. Besides, the boundary layer flow downstream of the active wall area as well as required wall deflections and the global damping effect on skin friction are presented in this paper

30 years of battling the cell wall.

Science.gov (United States)

Latgé, J P

2017-01-01

In Aspergillus fumigatus, like in other pathogenic fungi, the cell wall is essential for fungal growth as well as for resisting environmental stresses such as phagocytic killing. Most of the chemical analyses undertaken on the cell wall of A. fumigatus are focused on the mycelial cell wall because it is the vegetative stage of the fungus. However, the cell walls of the mycelium and conidium (which is the infective propagule) are different especially at the level of the surface layer, which plays a significant role in the interaction between A. fumigatus conidia and phagocytic cells of the immune system. In spite of the essential function of the cell wall in fungal life, progresses have been extremely slow in the understanding of biosynthesis as well in the identification of the key host responses against the cell wall components. A major difficulty is the fact that the composition and structural organization of the cell wall is not immutably set and is constantly reshuffled depending on the environmental conditions. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The plant cell wall integrity maintenance mechanism--a case study of a cell wall plasma membrane signaling network.

Science.gov (United States)

Hamann, Thorsten

2015-04-01

Some of the most important functions of plant cell walls are protection against biotic/abiotic stress and structural support during growth and development. A prerequisite for plant cell walls to perform these functions is the ability to perceive different types of stimuli in both qualitative and quantitative manners and initiate appropriate responses. The responses in turn involve adaptive changes in cellular and cell wall metabolism leading to modifications in the structures originally required for perception. While our knowledge about the underlying plant mechanisms is limited, results from Saccharomyces cerevisiae suggest the cell wall integrity maintenance mechanism represents an excellent example to illustrate how the molecular mechanisms responsible for stimulus perception, signal transduction and integration can function. Here I will review the available knowledge about the yeast cell wall integrity maintenance system for illustration purposes, summarize the limited knowledge available about the corresponding plant mechanism and discuss the relevance of the plant cell wall integrity maintenance mechanism in biotic stress responses. Copyright © 2014 Elsevier Ltd. All rights reserved.

Biologically-Oriented Processes in the Coastal Sea Ice Zone of the White Sea

Science.gov (United States)

Melnikov, I. A.

2002-12-01

The annual advance and retreat of sea ice is a major physical determinant of spatial and temporal changes in the structure and function of marine coastal biological communities. Sea ice biological data obtained in the tidal zone of Kandalaksha Gulf (White Sea) during 1996-2001 period will be presented. Previous observations in this area were mainly conducted during the ice-free summer season. However, there is little information on the ice-covered winter season (6-7 months duration), and, especially, on the sea-ice biology in the coastal zone within tidal regimes. During the January-May period time-series observations were conducted on transects along shorelines with coastal and fast ice. Trends in the annual extent of sea ice showed significant impacts on ice-associated biological communities. Three types of sea ice impact on kelps, balanoides, littorinas and amphipods are distinguished: (i) positive, when sea ice protects these populations from grinding (ii) negative, when ice grinds both fauna and flora, and (iii) a combined effect, when fast ice protects, but anchored ice grinds plant and animals. To understand the full spectrum of ecological problems caused by pollution on the coastal zone, as well as the problems of sea ice melting caused by global warming, an integrated, long-term study of the physical, chemical, and biological processes is needed.

Warming in the Nordic Seas, North Atlantic storms and thinning Arctic sea ice

Science.gov (United States)

Alexeev, Vladimir A.; Walsh, John E.; Ivanov, Vladimir V.; Semenov, Vladimir A.; Smirnov, Alexander V.

2017-08-01

Arctic sea ice over the last few decades has experienced a significant decline in coverage both in summer and winter. The currently warming Atlantic Water layer has a pronounced impact on sea ice in the Nordic Seas (including the Barents Sea). More open water combined with the prevailing atmospheric pattern of airflow from the southeast, and persistent North Atlantic storms such as the recent extremely strong Storm Frank in December 2015, lead to increased energy transport to the high Arctic. Each of these storms brings sizeable anomalies of heat to the high Arctic, resulting in significant warming and slowing down of sea ice growth or even melting. Our analysis indicates that the recently observed sea ice decline in the Nordic Seas during the cold season around Svalbard, Franz Joseph Land and Novaya Zemlya, and the associated heat release from open water into the atmosphere, contributed significantly to the increase in the downward longwave radiation throughout the entire Arctic. Added to other changes in the surface energy budget, this increase since the 1960s to the present is estimated to be at least 10 W m-2, which can result in thinner (up to at least 15-20 cm) Arctic ice at the end of the winter. This change in the surface budget is an important contributing factor accelerating the thinning of Arctic sea ice.

Gas from the wall socket

International Nuclear Information System (INIS)

Vermeer, B.

1997-01-01

A Dutch public utility (Obragas) introduces a new way to supply gas for their household clients in Helmond, Netherlands: the gas wall socket. The use of gas wall sockets must prevent the decrease of the market share for natural gas compared to the market share of electricity for households

Diplopia and Orbital Wall Fractures

NARCIS (Netherlands)

Boffano, P.; Roccia, F.; Gallesio, C.; Karagozoglu, K.H.; Forouzanfar, T.

2014-01-01

Diplopia is a symptom that is frequently associated with orbital wall fractures. The aim of this article was to present the incidence and patterns of diplopia after orbital wall blow-out fractures in 2 European centers, Turin and Amsterdam, and to identify any correlation between this symptom and

Diplopia and orbital wall fractures

NARCIS (Netherlands)

Boffano, P.; Roccia, F.; Gallesio, C.; Karagozoglu, K.H.; Forouzanfar, T.

2014-01-01

Diplopia is a symptom that is frequently associated with orbital wall fractures. The aim of this article was to present the incidence and patterns of diplopia after orbital wall blow-out fractures in 2 European centers, Turin and Amsterdam, and to identify any correlation between this symptom and

Influence of Coherent Structures on the Wall Shear Stress in Axial Flow Between a Cylinder and a Plane Wall

International Nuclear Information System (INIS)

Khabbouchi, Imed; Guellouz, Mohamed Sadok; Tavoularis, Stavros

2009-01-01

Synchronised hot-film and hot-wire measurements were made in the narrower region of a rectangular channel containing a cylindrical rod. The hot-film probe was mounted flush with the channel bottom wall to measure the wall shear stress, while the hot-wire probe was placed at a fixed position, selected in order to easily detect the passage of coherent structures. Mean and rms profiles of the wall shear stress show the influence of the gap to diameter ratio on their respective distributions. The latter presented peculiarities that could only be explained by the presence of coherent structures in the flow between the rod and the wall. Evidence of this presence is seen in the velocity power spectra. The strong influence of the coherent structures on the wall shear stress spatial and temporal distributions is established through velocity-wall shear stress cross-correlations functions and through conditionally sampled measurements

Polarimetric signatures of sea ice in the Greenland Sea

DEFF Research Database (Denmark)

Skriver, Henning; Pedersen, Leif Toudal

1995-01-01

Polarimetric SAR data of sea ice have been acquired by the Danish polarimetric SAR (EMISAR) during a mission at the Greenland Sea in August 1994. Video recordings from a low-altitude acquisition have been used for interpretation of the SAR data. Also, ERS-1 SAR data and NOAA AVHRR-data have been...

Arabidopsis Regenerating Protoplast: A Powerful Model System for Combining the Proteomics of Cell Wall Proteins and the Visualization of Cell Wall Dynamics

OpenAIRE

Yokoyama, Ryusuke; Kuki, Hiroaki; Kuroha, Takeshi; Nishitani, Kazuhiko

2016-01-01

The development of a range of sub-proteomic approaches to the plant cell wall has identified many of the cell wall proteins. However, it remains difficult to elucidate the precise biological role of each protein and the cell wall dynamics driven by their actions. The plant protoplast provides an excellent means not only for characterizing cell wall proteins, but also for visualizing the dynamics of cell wall regeneration, during which cell wall proteins are secreted. It therefore offers a uni...

Wall Turbulence.

Science.gov (United States)

Hanratty, Thomas J.

1980-01-01

This paper gives an account of research on the structure of turbulence close to a solid boundary. Included is a method to study the flow close to the wall of a pipe without interferring with it. (Author/JN)

Temperature, salinity, and nutrients data collected from North Atlantic Ocean, White Sea, Mediterranean Sea, Black Sea, and Sea of Azov from 1924-03-19 to 1989-11-19 by multiple Soviet Union institutes (NODC Accession 0077413)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Temperature, salinity, and nutrients data collected from North Atlantic Ocean, White Sea, Mediterranean Sea, Black Sea, and Sea of Azov from 1924-03-19 to 1989-11-19...

Sideways wall force produced during tokamak disruptions

Science.gov (United States)

Strauss, H.; Paccagnella, R.; Breslau, J.; Sugiyama, L.; Jardin, S.

2013-07-01

A critical issue for ITER is to evaluate the forces produced on the surrounding conducting structures during plasma disruptions. We calculate the non-axisymmetric ‘sideways’ wall force Fx, produced in disruptions. Simulations were carried out of disruptions produced by destabilization of n = 1 modes by a vertical displacement event (VDE). The force depends strongly on γτwall, where γ is the mode growth rate and τwall is the wall penetration time, and is largest for γτwall = constant, which depends on initial conditions. Simulations of disruptions caused by a model of massive gas injection were also performed. It was found that the wall force increases approximately offset linearly with the displacement from the magnetic axis produced by a VDE. These results are also obtained with an analytical model. Disruptions are accompanied by toroidal variation of the plasma current Iφ. This is caused by toroidal variation of the halo current, as verified computationally and analytically.

Deposit and scale prevention methods in thermal sea water desalination

International Nuclear Information System (INIS)

Froehner, K.R.

1977-01-01

Introductory remarks deal with the 'fouling factor' and its influence on the overall heat transfer coefficient of msf evaporators. The composition of the matter dissolved in sea water and the thermal and chemical properties lead to formation of alkaline scale or even hard, sulphate scale on the heat exchanger tube walls and can hamper plant operation and economics seriously. Among the scale prevention methods are 1) pH control by acid dosing (decarbonation), 2) 'threshold treatment' by dosing of inhibitors of different kind, 3) mechanical cleaning by sponge rubber balls guided through the heat exchanger tubes, in general combined with methods no. 1 or 2, and 4) application of a scale crystals germ slurry (seeding). Mention is made of several other scale prevention proposals. The problems encountered with marine life (suspension, deposit, growth) in desalination plants are touched. (orig.) [de

Raising the Dead without a Red Sea-Dead Sea project? Hydro-economics and governance

Directory of Open Access Journals (Sweden)

D. E. Rosenberg

2011-04-01

Full Text Available Seven decades of extractions have dramatically reduced Jordan River flows, lowered the Dead Sea level, opened sink holes, and caused other environmental problems. The fix Jordan, Israel, and the Palestinians propose would build an expensive multipurpose conveyance project from the Red Sea to the Dead Sea that would also generate hydropower and desalinate water. This paper compares the Red-Dead project to alternatives that may also raise the Dead Sea level. Hydro-economic model results for the Jordan-Israel-Palestinian inter-tied water systems show two restoration alternatives are more economically viable than the proposed Red-Dead project. Many decentralized new supply, wastewater reuse, conveyance, conservation, and leak reduction projects and programs in each country can together increase economic benefits and reliably deliver up to 900 MCM yr⁻¹ to the Dead Sea. Similarly, a smaller Red-Dead project that only generates hydropower can deliver large flows to the Dead Sea when the sale price of generated electricity is sufficiently high. However, for all restoration options, net benefits fall and water scarcity rises as flows to the Dead Sea increase. This finding suggests (i each country has no individual incentive to return water to the Dead Sea, and (ii outside institutions that seek to raise the Dead must also offer countries direct incentives to deliver water to the Sea besides building the countries new infrastructure.

Cell wall heterogeneity in root development of Arabidopsis

Directory of Open Access Journals (Sweden)

Marc Somssich

2016-08-01

Full Text Available Plant cell walls provide stability and protection to plant cells. During growth and development the composition of cell walls changes, but provides enough strength to withstand the turgor of the cells. Hence, cell walls are highly flexible and diverse in nature. These characteristics are important during root growth, as plant roots consist of radial patterns of cells that have diverse functions and that are at different developmental stages along the growth axis. Young stem cell daughters undergo a series of rapid cell divisions, during which new cell walls are formed that are highly dynamic, and that support rapid anisotropic cell expansion. Once the cells have differentiated, the walls of specific cell types need to comply with and support different cell functions. For example, a newly formed root hair needs to be able to break through the surrounding soil, while endodermal cells modify their walls at distinct positions to form Casparian strips between them. Hence, the cell walls are modified and rebuilt while cells transit through different developmental stages. In addition, the cell walls of roots readjust to their environment to support growth and to maximize nutrient uptake. Many of these modifications are likely driven by different developmental and stress signalling pathways. However, our understanding of how such pathways affect cell wall modifications and what enzymes are involved remain largely unknown. In this review we aim to compile data linking cell wall content and re-modelling to developmental stages of root cells, and dissect how root cell walls respond to certain environmental changes.

Economics of abdominal wall reconstruction.

Science.gov (United States)

Bower, Curtis; Roth, J Scott

2013-10-01

The economic aspects of abdominal wall reconstruction are frequently overlooked, although understandings of the financial implications are essential in providing cost-efficient health care. Ventral hernia repairs are frequently performed surgical procedures with significant economic ramifications for employers, insurers, providers, and patients because of the volume of procedures, complication rates, the significant rate of recurrence, and escalating costs. Because biological mesh materials add significant expense to the costs of treating complex abdominal wall hernias, the role of such costly materials needs to be better defined to ensure the most cost-efficient and effective treatments for ventral abdominal wall hernias. Copyright © 2013 Elsevier Inc. All rights reserved.

Theory of topological edges and domain walls

NARCIS (Netherlands)

Bais, F.A.; Slingerland, J.K.; Haaker, S.M.

2009-01-01

We investigate domain walls between topologically ordered phases in two spatial dimensions. We present a method which allows for the determination of the superselection sectors of excitations of such walls and which leads to a unified description of the kinematics of a wall and the two phases to

[Multiple scattering of visible and infrared light by sea fog over wind driving rough sea surface].

Science.gov (United States)

Sun, Xian-Ming; Wang, Hai-Hua; Lei, Cheng-Xin; Shen, Jin

2013-08-01

The present paper is concerned with computing the multiple scattering characteristics of a sea fog-sea surface couple system within this context. The single scattering characteristics of sea fog were studied by Mie theory, and the multiple scattering of sunlight by single sea fog layer was studied by radiative transfer theory. The reflection function of a statistically rough ocean surface was obtained using the standard Kirchhoff formulation, with shadowing effects taken into account. The reflection properties of the combined sea fog and ocean surface were obtained employing the adding method, and the results indicated that the reflected light intensity of sea fog increased with the sea background.

An NPARC Turbulence Module with Wall Functions

Science.gov (United States)

Zhu, J.; Shih, T.-H.

1997-01-01

The turbulence module recently developed for the NPARC code has been extended to include wall functions. The Van Driest transformation is used so that the wall functions can be applied to both incompressible and compressible flows. The module is equipped with three two-equation K-epsilon turbulence models: Chien, Shih-Lumley and CMOTR models. Details of the wall functions as well as their numerical implementation are reported. It is shown that the inappropriate artificial viscosity in the near-wall region has a big influence on the solution of the wall function approach. A simple way to eliminate this influence is proposed, which gives satisfactory results during the code validation. The module can be easily linked to the NPARC code for practical applications.

Aging near the wall in colloidal glasses

Science.gov (United States)

Cao, Cong; Huang, Xinru; Weeks, Eric

In a colloidal glass system, particles move slower as sample ages. In addition, their motions may be affected by their local structure, and this structure will be different near a wall. We examine how the aging process near a wall differs from that in the bulk of the sample. In particular, we use a confocal microscope to observe 3D motion in a bidisperse colloidal glass sample. We find that flat walls induce the particles to organize into layers. The aging process behaves differently near the boundary, especially within the first three layers. Particle motion near the wall is noticeably slower but also changes less dramatically with age. We compare and contrast aging seen in samples with flat and rough walls.

Frost flowers and sea-salt aerosols over seasonal sea-ice areas in northwestern Greenland during winter–spring

Directory of Open Access Journals (Sweden)

K. Hara

2017-07-01

Full Text Available Sea salts and halogens in aerosols, frost flowers, and brine play an important role in atmospheric chemistry in polar regions. Simultaneous sampling and observations of frost flowers, brine, and aerosol particles were conducted around Siorapaluk in northwestern Greenland during December 2013 to March 2014. Results show that water-soluble frost flower and brine components are sea-salt components (e.g., Na+, Cl−, Mg2+, K+, Ca2+, Br−, and iodine. Concentration factors of sea-salt components of frost flowers and brine relative to seawater were 1.14–3.67. Sea-salt enrichment of Mg2+, K+, Ca2+, and halogens (Cl−, Br−, and iodine in frost flowers is associated with sea-salt fractionation by precipitation of mirabilite and hydrohalite. High aerosol number concentrations correspond to the occurrence of higher abundance of sea-salt particles in both coarse and fine modes, and blowing snow and strong winds. Aerosol number concentrations, particularly in coarse mode, are increased considerably by release from the sea-ice surface under strong wind conditions. Sulfate depletion by sea-salt fractionation was found to be limited in sea-salt aerosols because of the presence of non-sea-salt (NSS SO42−. However, coarse and fine sea-salt particles were found to be rich in Mg. Strong Mg enrichment might be more likely to proceed in fine sea-salt particles. Magnesium-rich sea-salt particles might be released from the surface of snow and slush layer (brine on sea ice and frost flowers. Mirabilite-like and ikaite-like particles were identified only in aerosol samples collected near new sea-ice areas. From the field evidence and results from earlier studies, we propose and describe sea-salt cycles in seasonal sea-ice areas.

Frost flowers and sea-salt aerosols over seasonal sea-ice areas in northwestern Greenland during winter-spring

Science.gov (United States)

Hara, Keiichiro; Matoba, Sumito; Hirabayashi, Motohiro; Yamasaki, Tetsuhide

2017-07-01

Sea salts and halogens in aerosols, frost flowers, and brine play an important role in atmospheric chemistry in polar regions. Simultaneous sampling and observations of frost flowers, brine, and aerosol particles were conducted around Siorapaluk in northwestern Greenland during December 2013 to March 2014. Results show that water-soluble frost flower and brine components are sea-salt components (e.g., Na+, Cl-, Mg2+, K+, Ca2+, Br-, and iodine). Concentration factors of sea-salt components of frost flowers and brine relative to seawater were 1.14-3.67. Sea-salt enrichment of Mg2+, K+, Ca2+, and halogens (Cl-, Br-, and iodine) in frost flowers is associated with sea-salt fractionation by precipitation of mirabilite and hydrohalite. High aerosol number concentrations correspond to the occurrence of higher abundance of sea-salt particles in both coarse and fine modes, and blowing snow and strong winds. Aerosol number concentrations, particularly in coarse mode, are increased considerably by release from the sea-ice surface under strong wind conditions. Sulfate depletion by sea-salt fractionation was found to be limited in sea-salt aerosols because of the presence of non-sea-salt (NSS) SO42-. However, coarse and fine sea-salt particles were found to be rich in Mg. Strong Mg enrichment might be more likely to proceed in fine sea-salt particles. Magnesium-rich sea-salt particles might be released from the surface of snow and slush layer (brine) on sea ice and frost flowers. Mirabilite-like and ikaite-like particles were identified only in aerosol samples collected near new sea-ice areas. From the field evidence and results from earlier studies, we propose and describe sea-salt cycles in seasonal sea-ice areas.

Experimental studies on the geochemical behaviour of 54-Mn considering coastal and deep sea sediments

International Nuclear Information System (INIS)

Guegueniat, P.; Boust, D.; Aprosi, G.

1986-01-01

In order to study the geochemical behaviour of 54-Mn in the marine environment (Mn 2+ ) 200 sediments gathered in deep sea and in coastal waters were contaminated experimentally. To correlate the various results, the oxidation processes occuring with or without sediments should be specified. Without sediments, in 'blanks', the deposition rate of 54-Mn on the walls brings into play oxidation developing approximately according to a single order linear function. Consequently, it is characterized by a half-life (time for half 54-Mn to be retained) very similar to a residence time (Tsub(R)). In our water samples, Tsub(R) ranged from 12 to 150 days. (author)

An innovation wall model based on interlayer ventilation

International Nuclear Information System (INIS)

Feng Jinmei; Lian Zhiwei; Hou Zhijian

2008-01-01

The thermal characteristics of the external wall are important to the energy consumption of the air conditioning system. Great attention should also be paid to the energy loss of the air exhaust. An innovation wall model based on interlayer ventilation is presented in this paper. The interlayer ventilation wall combines the wall and air exhaust of heating, ventilating and air conditioning (HVAC). The results of the experiment show that the energy loss of the exhaust air can be fully recovered by the interlayer ventilation wall. The cooling load can be reduced greatly because the temperature difference between the internal surface of the interlayer ventilation wall and the indoor air is very small. Clearly, the small temperature difference can enhance thermal comfort. In order to popularize the interlayer ventilation wall, technical and economical analysis is presented in this paper. Based on the buildings in the Shanghai area and a standard air conditioning system, a 4 years payback period for interlayer ventilation wall implementation was found according to the analysis

Black Sea aerosols

International Nuclear Information System (INIS)

Hacisalihoglu, G.; Eliyakut, F.; Anwari, M.A.; Ataman, O.Y.; Balkas, T.I.; Tuncel, G.; Olmez, I.

1991-01-01

Shipboard, high volume air particulate samples were collected from the Black Sea atmosphere and analyzed by instrumental neutron activation analysis, atomic absorption spectrophotometry and ion chromatography for about 40 elements and ions. Concentrations of elements in the eastern and western parts of the Black Sea are different at the 95% confidence level, with lower concentrations in the eastern Black Sea. Back-trajectories and concentrations of elements in trajectory groups show that Europe accounts for more than 70% of the anthropogenic elements in the atmosphere. The average sulfate concentration was 7 μg/m 3 , which is comparable with rural sulfate levels in western Europe. Fluxes of elements from the atmosphere to the Black Sea are in good agreement with the results of similar flux calculations for other regions

Sea Surface Temperature Climate Data Record for the North Sea and Baltic Sea

DEFF Research Database (Denmark)

Høyer, Jacob L.; Karagali, Ioanna

2016-01-01

A 30-yr climate data record (CDR) of sea surface temperature (SST) has been produced with daily gap-free analysis fields for the North Sea and the Baltic Sea region from 1982 to 2012 by combining the Pathfinder AVHRR satellite data record with the Along-Track Scanning Radiometer (ATSR) Reprocessing...... for Climate (ARC) dataset and with in situ observations. A dynamical bias correction scheme adjusts the Pathfinder observations toward the ARC and in situ observations. Largest Pathfinder-ARC differences are found in the summer months, when the Pathfinder observations are up to 0.4 °C colder than the ARC...... observations on average. Validation against independent in situ observations shows a very stable performance of the data record, with a mean difference of -0.06 °C compared to moored buoys and a 0.46 °C standard deviation of the differences. The mean annual biases of the SST CDR are small for all years...

Investigation of Plant Cell Wall Properties: A Study of Contributions from the Nanoscale to the Macroscale Impacting Cell Wall Recalcitrance

Science.gov (United States)

Crowe, Jacob Dillon

Biochemical conversion of lignocellulosic biomass to fuel ethanol is one of a few challenging, yet opportune technologies that can reduce the consumption of petroleum-derived transportation fuels, while providing parallel reductions in greenhouse gas emissions. Biomass recalcitrance, or resistance to deconstruction, is a major technical challenge that limits effective conversion of biomass to fermentable sugars, often requiring a costly thermochemical pretreatment step to improve biomass deconstruction. Biomass recalcitrance is imparted largely by the secondary cell wall, a complex polymeric matrix of cell wall polysaccharides and aromatic heteropolymers, that provides structural stability to cells and enables plant upright growth. Polymers within the cell wall can vary both compositionally and structurally depending upon plant species and anatomical fraction, and have varied responses to thermochemical pretreatments. Cell wall properties impacting recalcitrance are still not well understood, and as a result, the goal of this dissertation is to investigate structural features of the cell wall contributing to recalcitrance (1) in diverse anatomical fractions of a single species, (2) in response to diverse pretreatments, and (3) resulting from genetic modification. In the first study, feedstock cell wall heterogeneity was investigated in anatomical (stem, leaf sheaths, and leaf blades) and internode fractions of switchgrass at varying tissue maturities. Lignin content was observed as the key contributor to recalcitrance in maturing stem tissues only, with non-cellulosic substituted glucuronoarabinoxylans and pectic polysaccharides contributing to cell wall recalcitrance in leaf sheath and leaf blades. Hydroxycinnamate (i.e., saponifiable p-coumarate and ferulate) content along with xylan and pectin extractability decreased with tissue maturity, suggesting lignification is only one component imparting maturity specific cell wall recalcitrance. In the second study

Dietary Yeast Cell Wall Extract Alters the Proteome of the Skin Mucous Barrier in Atlantic Salmon (Salmo salar: Increased Abundance and Expression of a Calreticulin-Like Protein.

Directory of Open Access Journals (Sweden)

Giulia Micallef

Full Text Available In order to improve fish health and reduce use of chemotherapeutants in aquaculture production, the immunomodulatory effect of various nutritional ingredients has been explored. In salmon, there is evidence that functional feeds can reduce the abundance of sea lice. This study aimed to determine if there were consistent changes in the skin mucus proteome that could serve as a biomarker for dietary yeast cell wall extract. The effect of dietary yeast cell wall extract on the skin mucus proteome of Atlantic salmon was examined using two-dimensional gel electrophoresis. Forty-nine spots showed a statistically significant change in their normalised volumes between the control and yeast cell wall diets. Thirteen spots were successfully identified by peptide fragment fingerprinting and LC-MS/MS and these belonged to a variety of functions and pathways. To assess the validity of the results from the proteome approach, the gene expression of a selection of these proteins was studied in skin mRNA from two different independent feeding trials using yeast cell wall extracts. A calreticulin-like protein increased in abundance at both the protein and transcript level in response to dietary yeast cell wall extract. The calreticulin-like protein was identified as a possible biomarker for yeast-derived functional feeds since it showed the most consistent change in expression in both the mucus proteome and skin transcriptome. The discovery of such a biomarker is expected to quicken the pace of research in the application of yeast cell wall extracts.

Motional Effect on Wall Shear Stresses

DEFF Research Database (Denmark)

Kock, Samuel Alberg; Torben Fründ, Ernst; Yong Kim, Won

Atherosclerosis is the leading cause of death and severe disability. Wall Shear Stress (WSS), the stress exerted on vessel walls by the flowing blood is a key factor in the development of atherosclerosis. Computational Fluid Dynamics (CFD) is widely used for WSS estimations. Most CFD simulations...... are based on static models to ease computational burden leading to inaccurate estimations. The aim of this work was to estimate the effect of vessel wall deformations (expansion and bending) on WSS levels....

Fin whales and microplastics: The Mediterranean Sea and the Sea of Cortez scenarios

International Nuclear Information System (INIS)

Fossi, Maria Cristina; Marsili, Letizia; Baini, Matteo; Giannetti, Matteo; Coppola, Daniele; Guerranti, Cristiana; Caliani, Ilaria; Minutoli, Roberta; Lauriano, Giancarlo; Finoia, Maria Grazia; Rubegni, Fabrizio; Panigada, Simone; Bérubé, Martine; Urbán Ramírez, Jorge; Panti, Cristina

2016-01-01

The impact that microplastics have on baleen whales is a question that remains largely unexplored. This study examined the interaction between free-ranging fin whales (Balaenoptera physalus) and microplastics by comparing populations living in two semi-enclosed basins, the Mediterranean Sea and the Sea of Cortez (Gulf of California, Mexico). The results indicate that a considerable abundance of microplastics and plastic additives exists in the neustonic samples from Pelagos Sanctuary of the Mediterranean Sea, and that pelagic areas containing high densities of microplastics overlap with whale feeding grounds, suggesting that whales are exposed to microplastics during foraging; this was confirmed by the observation of a temporal increase in toxicological stress in whales. Given the abundance of microplastics in the Mediterranean environment, along with the high concentrations of Persistent Bioaccumulative and Toxic (PBT) chemicals, plastic additives and biomarker responses detected in the biopsies of Mediterranean whales as compared to those in whales inhabiting the Sea of Cortez, we believe that exposure to microplastics because of direct ingestion and consumption of contaminated prey poses a major threat to the health of fin whales in the Mediterranean Sea. - Highlights: • Microplastics and phthalates were higher in the Mediterranean Sea than in the Sea of Cortez. • The overlap between the whale feeding areas and high microplastic density shows the risk of interaction. • Data suggest an increasing risk of chemical transfer from microplastic to whales during the foraging. • Mediterranean whales are exposed to higher ecotoxicological threat of than Sea of Cortez whales. - This study identified temporal and regional ecotoxicological variations in free-ranging fin whales inhabiting two seas different characterized by different microplastic abundance.

Oocyst wall formation and composition in coccidian parasites

Directory of Open Access Journals (Sweden)

Kelly Mai

2009-03-01

Full Text Available The oocyst wall of coccidian parasites is a robust structure that is resistant to a variety of environmental and chemical insults. This resilience allows oocysts to survive for long periods, facilitating transmission from host to host. The wall is bilayered and is formed by the sequential release of the contents of two specialized organelles - wall forming body 1 and wall forming body 2 - found in the macrogametocyte stage of Coccidia. The oocyst wall is over 90% protein but few of these proteins have been studied. One group is cysteine-rich and may be presumed to crosslink via disulphide bridges, though this is yet to be investigated. Another group of wall proteins is rich in tyrosine. These proteins, which range in size from 8-31 kDa, are derived from larger precursors of 56 and 82 kDa found in the wall forming bodies. Proteases may catalyze processing of the precursors into tyrosine-rich peptides, which are then oxidatively crosslinked in a reaction catalyzed by peroxidases. In support of this hypothesis, the oocyst wall has high levels of dityrosine bonds. These dityrosine crosslinked proteins may provide a structural matrix for assembly of the oocyst wall and contribute to its resilience.

Mechanical response of wall-patterned GaAs surface

International Nuclear Information System (INIS)

Le Bourhis, E.; Patriarche, G.

2005-01-01

Wall-patterned GaAs surfaces have been elaborated by photolithography and dry etching. Different surfaces were produced in order to change the aspect ratio of the walls formed at the substrate surface. The mechanical behaviour of individual walls was investigated by nanoindentation and the responses were compared to that of a standard bulk reference (flat surface). Deviation from the bulk response is detected in a load range of 1-25 mN depending on the aspect ratio of the walls. A central plastic zone criterion is proposed in view of transmission electron microscopy images of indented walls and allows the prediction of the response deviation of a given wall if its width is known. The mechanical response of the different types of walls is further investigated in terms of stiffness, total penetration of indenter and apparent hardness, and is scanned in relation to the proximity of a wall side. Overall results show that contact stiffness remains almost unaffected by aspect ratio, while penetration drastically increases because of the free sides of the wall as compared to a flat surface (bulk substrate). The application of substrate patterning for optoelectronic devices is discussed in the perspective of eliminating residual dislocations appearing in mismatched structures

Spalling of concrete walls under blast load

International Nuclear Information System (INIS)

Kot, C.A.

1977-01-01

A common effect of the detonation of explosives in close proximity of concrete shield walls is the spalling (scabbing) of the back face of the wall. Spalling is caused by the free surface reflection of the shock wave induced in the wall by high pressure air blast and occurs whenever the dynamic tensile rupture strength is exceeded. While a complex process, reasonable analytical spall estimates can be obtained for brittle materials with low tensile strengths, such as concrete, by assuming elastic material behavior and instantaneous spall formation. Specifically, the spall thicknesses and velocities for both normal and oblique incidence of the shock wave on the back face of the wall are calculated. The complex exponential decay wave forms of the air blast are locally approximated by simple power law expressions. Variations of blast wave strength with distance to the wall, charge weight and angle of incidence are taken into consideration. The shock wave decay in the wall is also accounted for by assuming elastic wave propagation. For explosions close-in to the wall, where the reflected blast wave pressures are sufficiently high, multiple spall layers are formed. Successive spall layers are of increasing thickness, at the same time the spall velocities decrease. The spall predictions based on elastic theory are in overall agreement with experimntal results and provide a rapid means of estimating spalling trends of concrete walls subjected to air blast. (Auth.)

The "Brick Wall" Graphic Organizer

Science.gov (United States)

Matteson, Shirley M.

2016-01-01

A brick wall provides a fitting description of what happens when teachers try to teach a concept for which students are unprepared. When students are unsuccessful academically, their foundational knowledge may be missing, incomplete, or incorrect. As a result, students "hit a brick wall," and their academic progress stops because they do…

Degradation processes and the methods of securing wall crests

Directory of Open Access Journals (Sweden)

Maciej Trochonowicz

2017-12-01

Full Text Available The protection of historical ruins requires solution of doctrinal and technical problems. Technical problems concern above all preservation of walls, which are exposed to the influence of atmospheric factors. The problem that needs to be solved in any historic ruin is securing of wall crests. Form of protection of the wall crests depends on many factors, mainly technical features of the wall and architectural and conservatory vision. The following article presents three aspects important for protection of wall crests. Firstly, analysis of features of the wall as a structure, secondly the characteristics of destructive agents, thirdly forms of protection of wall crests. In the summary of the following article, advantages and disadvantages of each method of preservation of the wall crests were presented.

Prenatal MRI evaluation of limb-body wall complex

Energy Technology Data Exchange (ETDEWEB)

Aguirre-Pascual, Elisa [Perelman School of Medicine at the University of Pennsylvania, Department of Radiology, The Children' s Hospital of Philadelphia, Philadelphia, PA (United States); Hospital Universitario Doce de Octubre, Department of Radiology, Madrid (Spain); Epelman, Monica [Perelman School of Medicine at the University of Pennsylvania, Department of Radiology, The Children' s Hospital of Philadelphia, Philadelphia, PA (United States); Nemours Children' s Hospital, Department of Medical Imaging, Orlando, FL (United States); Johnson, Ann M.; Chauvin, Nancy A.; Coleman, Beverly G.; Victoria, Teresa [Perelman School of Medicine at the University of Pennsylvania, Department of Radiology, The Children' s Hospital of Philadelphia, Philadelphia, PA (United States)

2014-11-15

The sonographic (US) features of limb-body wall complex have been well documented; however the literature regarding the findings on MRI in limb-body wall complex is scant. To characterize the prenatal MRI features of limb-body wall complex. We performed a retrospective review of all MRI scans of fetuses diagnosed with limb-body wall complex at our institution from 2001 to 2011. Fetuses without correlating US scans or follow-up information were excluded. Three pediatric radiologists blinded to the specific US findings reviewed the prenatal MRIs. Images were evaluated for the organ location and attachment, the body part affected, characterization of the body wall defect, and spinal, limb and umbilical cord abnormalities. Ten subjects met inclusion criteria. MRI was able to detect and characterize the body part affected and associated abnormalities. All fetuses had ventral wall defects, a small thorax and herniated liver and bowel. The kidneys were extracorporeal in three cases. The extruded organs were attached to the placenta or the uterine wall in all cases. Abnormal spinal curvatures of various degrees of severity were present in all cases. Eight cases had a short, uncoiled cord. Limb anomalies were present in 6 of the 10 cases. We illustrate the common fetal MRI findings of limb-body wall complex. The prenatal diagnosis of limb-body wall complex and the differentiation of this defect from treatable abdominal wall defects are crucial to providing appropriate guidance for patient counseling and management. (orig.)

Three modes of interdecadal trends in sea surface temperature and sea surface height

Science.gov (United States)

Gnanadesikan, A.; Pradal, M.

2013-12-01

It might be thought that sea surface height and sea surface temperature would be tightly related. We show that this is not necessarily the case on a global scale. We analysed this relationship in a suite of coupled climate models run under 1860 forcing conditions. The models are low-resolution variants of the GFDL Earth System Model, reported in Galbraith et al. (J. Clim. 2011). 1. Correlated changes in global sea surface height and global sea surface temperature. This mode corresponds to opening and closing of convective chimneys in the Southern Ocean. As the Southern Ocean destratifies, sea ice formation is suppressed during the winter and more heat is taken up during the summer. This mode of variability is highly correlated with changes in the top of the atmosphere radiative budget and weakly correlated with changes in the deep ocean circulation. 2. Uncorrelated changes in global sea surface height and global sea surface temperature. This mode of variability is associated with interdecadal variabliity in tropical winds. Changes in the advective flux of heat to the surface ocean play a critical role in driving these changes, which also result in significant local changes in sea level. Changes sea ice over the Southern Ocean still result in changes in solar absorption, but these are now largely cancelled by changes in outgoing longwave radiation. 3. Anticorrelated changes in global sea surface height and global sea surface temperatures. By varying the lateral diffusion coefficient in the ocean model, we are able to enhance and suppress convection in the Southern and Northern Pacific Oceans. Increasing the lateral diffusion coefficients shifts the balance sources of deep water away from the warm salty deep water of the North Atlantic and towards cold fresh deep water from the other two regions. As a result, even though the planet as a whole warms, the deep ocean cools and sea level falls, with changes of order 30 cm over 500 years. The increase in solar absorption

Failure modes of low-rise shear walls

International Nuclear Information System (INIS)

Farrar, C.R.; Reed, J.W.; Salmon, M.W.

1993-01-01

A summary of available data concerning the structural response of low-rise shear walls is presented. These data will be used to address two failure modes associated with shear wall structures. First, the data concerning the seismic capacity of the shear walls are examined, with emphasis on excessive deformations that can cause equipment failure. Second, the data concerning the dynamic properties of shear walls (stiffness and damping) that are necessary for computing the seismic inputs to attached equipment are summarized. This case addresses the failure of equipment when the structure remains functional

KRE5 Suppression Induces Cell Wall Stress and Alternative ER Stress Response Required for Maintaining Cell Wall Integrity in Candida glabrata

Science.gov (United States)

Sasaki, Masato; Ito, Fumie; Aoyama, Toshio; Sato-Okamoto, Michiyo; Takahashi-Nakaguchi, Azusa; Chibana, Hiroji; Shibata, Nobuyuki

2016-01-01

The maintenance of cell wall integrity in fungi is required for normal cell growth, division, hyphae formation, and antifungal tolerance. We observed that endoplasmic reticulum stress regulated cell wall integrity in Candida glabrata, which possesses uniquely evolved mechanisms for unfolded protein response mechanisms. Tetracycline-mediated suppression of KRE5, which encodes a predicted UDP-glucose:glycoprotein glucosyltransferase localized in the endoplasmic reticulum, significantly increased cell wall chitin content and decreased cell wall β-1,6-glucan content. KRE5 repression induced endoplasmic reticulum stress-related gene expression and MAP kinase pathway activation, including Slt2p and Hog1p phosphorylation, through the cell wall integrity signaling pathway. Moreover, the calcineurin pathway negatively regulated cell wall integrity, but not the reduction of β-1,6-glucan content. These results indicate that KRE5 is required for maintaining both endoplasmic reticulum homeostasis and cell wall integrity, and that the calcineurin pathway acts as a regulator of chitin-glucan balance in the cell wall and as an alternative mediator of endoplasmic reticulum stress in C. glabrata. PMID:27548283

Increased Land Use by Chukchi Sea Polar Bears in Relation to Changing Sea Ice Conditions.

Science.gov (United States)

Rode, Karyn D; Wilson, Ryan R; Regehr, Eric V; St Martin, Michelle; Douglas, David C; Olson, Jay

2015-01-01

Recent observations suggest that polar bears (Ursus maritimus) are increasingly using land habitats in some parts of their range, where they have minimal access to their preferred prey, likely in response to loss of their sea ice habitat associated with climatic warming. We used location data from female polar bears fit with satellite radio collars to compare land use patterns in the Chukchi Sea between two periods (1986-1995 and 2008-2013) when substantial summer sea-ice loss occurred. In both time periods, polar bears predominantly occupied sea-ice, although land was used during the summer sea-ice retreat and during the winter for maternal denning. However, the proportion of bears on land for > 7 days between August and October increased between the two periods from 20.0% to 38.9%, and the average duration on land increased by 30 days. The majority of bears that used land in the summer and for denning came to Wrangel and Herald Islands (Russia), highlighting the importance of these northernmost land habitats to Chukchi Sea polar bears. Where bears summered and denned, and how long they spent there, was related to the timing and duration of sea ice retreat. Our results are consistent with other studies supporting increased land use as a common response of polar bears to sea-ice loss. Implications of increased land use for Chukchi Sea polar bears are unclear, because a recent study observed no change in body condition or reproductive indices between the two periods considered here. This result suggests that the ecology of this region may provide a degree of resilience to sea ice loss. However, projections of continued sea ice loss suggest that polar bears in the Chukchi Sea and other parts of the Arctic may increasingly use land habitats in the future, which has the potential to increase nutritional stress and human-polar bear interactions.

Intermittent sea-level acceleration

Science.gov (United States)

Olivieri, M.; Spada, G.

2013-10-01

Using instrumental observations from the Permanent Service for Mean Sea Level (PSMSL), we provide a new assessment of the global sea-level acceleration for the last ~ 2 centuries (1820-2010). Our results, obtained by a stack of tide gauge time series, confirm the existence of a global sea-level acceleration (GSLA) and, coherently with independent assessments so far, they point to a value close to 0.01 mm/yr2. However, differently from previous studies, we discuss how change points or abrupt inflections in individual sea-level time series have contributed to the GSLA. Our analysis, based on methods borrowed from econometrics, suggests the existence of two distinct driving mechanisms for the GSLA, both involving a minority of tide gauges globally. The first effectively implies a gradual increase in the rate of sea-level rise at individual tide gauges, while the second is manifest through a sequence of catastrophic variations of the sea-level trend. These occurred intermittently since the end of the 19th century and became more frequent during the last four decades.

GHRSST Level 4 DMI_OI North Sea and Baltic Sea Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis by the Danish...

Regulatory heterochronies and loose temporal scaling between sea star and sea urchin regulatory circuits.

Science.gov (United States)

Gildor, Tsvia; Hinman, Veronica; Ben-Tabou-De-Leon, Smadar

2017-01-01

It has long been argued that heterochrony, a change in relative timing of a developmental process, is a major source of evolutionary innovation. Heterochronic changes of regulatory gene activation could be the underlying molecular mechanism driving heterochronic changes through evolution. Here, we compare the temporal expression profiles of key regulatory circuits between sea urchin and sea star, representative of two classes of Echinoderms that shared a common ancestor about 500 million years ago. The morphologies of the sea urchin and sea star embryos are largely comparable, yet, differences in certain mesodermal cell types and ectodermal patterning result in distinct larval body plans. We generated high resolution temporal profiles of 17 mesodermally-, endodermally- and ectodermally-expressed regulatory genes in the sea star, Patiria miniata, and compared these to their orthologs in the Mediterranean sea urchin, Paracentrotus lividus. We found that the maternal to zygotic transition is delayed in the sea star compared to the sea urchin, in agreement with the longer cleavage stage in the sea star. Interestingly, the order of gene activation shows the highest variation in the relatively diverged mesodermal circuit, while the correlations of expression dynamics are the highest in the strongly conserved endodermal circuit. We detected loose scaling of the developmental rates of these species and observed interspecies heterochronies within all studied regulatory circuits. Thus, after 500 million years of parallel evolution, mild heterochronies between the species are frequently observed and the tight temporal scaling observed for closely related species no longer holds.

The Satellite Passive-Microwave Record of Sea Ice in the Ross Sea Since Late 1978

Science.gov (United States)

Parkinson, Claire L.

2009-01-01

Satellites have provided us with a remarkable ability to monitor many aspects of the globe day-in and day-out and sea ice is one of numerous variables that by now have quite substantial satellite records. Passive-microwave data have been particularly valuable in sea ice monitoring, with a record that extends back to August 1987 on daily basis (for most of the period), to November 1970 on a less complete basis (again for most of the period), and to December 1972 on a less complete basis. For the period since November 1970, Ross Sea sea ice imagery is available at spatial resolution of approximately 25 km. This allows good depictions of the seasonal advance and retreat of the ice cover each year, along with its marked interannual variability. The Ross Sea ice extent typically reaches a minimum of approximately 0.7 x 10(exp 6) square kilometers in February, rising to a maximum of approximately 4.0 x 10(exp 6) square kilometers in September, with much variability among years for both those numbers. The Ross Sea images show clearly the day-by-day activity greatly from year to year. Animations of the data help to highlight the dynamic nature of the Ross Sea ice cover. The satellite data also allow calculation of trends in the ice cover over the period of the satellite record. Using linear least-squares fits, the Ross Sea ice extent increased at an average rate of 12,600 plus or minus 1,800 square kilometers per year between November 1978 and December 2007, with every month exhibiting increased ice extent and the rates of increase ranging from a low of 7,500 plus or minus 5,000 square kilometers per year for the February ice extents to a high of 20,300 plus or minus 6,100 kilometers per year for the October ice extents. On a yearly average basis, for 1979-2007 the Ross Sea ice extent increased at a rate of 4.8 plus or minus 1.6 % per decade. Placing the Ross Sea in the context of the Southern Ocean as a whole, over the November 1978-December 2007 period the Ross Sea had

Chest Wall tumor: combined management

International Nuclear Information System (INIS)

Rao Bhaskar, N.

1997-01-01

Cancer is relatively rare disease among children and adolescents. The incidence of solid tumors other than CNS is less than 2/100,000. Tumors of the chest wall can arise either from the somatic tissue or ribs. These are rare, so either institutional reviews or multi institutional studies should determine optimal therapeutic management. Of the bony chest wall, Ewing's sarcoma or the family of tumor (peripheral neuro epithelioma, Askin tumor), are the most common. These lesions are lytic and have associated large extra pleural component. This large extra pleural component often necessitates major chest wall resection (3 or more ribs), and when lower ribs are involved, this entails resection of portion of diaphragm. Despite this resection, survival in the early 1970 was 10-20%. Since 1970 multi agent chemotherapy has increased survival rates. of importance, however, is these regimens have caused significant reduction of these extra pleural components so that major chest wall resections have become a rarity. With improved survival and decreased morbidity preoperative chemotherapy followed by surgery is now the accepted modality of treatment. Another major advantage of this regimen is that potential radiation therapy may be obviated. The most common chest wall lesion is rhabdomyosarcoma. In the IRS study of 1620 RMS patients, in 141 (9%) the primary lesion was in the chest wall. these are primarily alveolar histology. when lesions were superficial, wide local excision with supplemental radiation therapy was associated with low morbidity and good overall survival. however, a majority have significant intra- thoracic components. in these circumstances the resectability rate is less than 30% and the survival poor. Other lesions include non rhabdomyosarcomas, eosinophilic granuloma, chondrosarcoma, and osteomyelitis. The management of these lesions varies according to extent, histology, and patient characteristics

A heavy sea fog event over the Yellow Sea in March 2005: Analysis and numerical modeling

Science.gov (United States)

Gao, Shanhong; Lin, Hang; Shen, Biao; Fu, Gang

2007-02-01

In this paper, a heavy sea fog episode that occurred over the Yellow Sea on 9 March 2005 is investigated. The sea fog patch, with a spatial scale of several hundred kilometers at its mature stage, reduced visibility along the Shandong Peninsula coast to 100 m or much less at some sites. Satellite images, surface observations and soundings at islands and coasts, and analyses from the Japan Meteorology Agency (JMA) are used to describe and analyze this event. The analysis indicates that this sea fog can be categorized as advection cooling fog. The main features of this sea fog including fog area and its movement are reasonably reproduced by the Fifth-generation Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model (MM5). Model results suggest that the formation and evolution of this event can be outlined as: (1) southerly warm/moist advection of low-level air resulted in a strong sea-surface-based inversion with a thickness of about 600 m; (2) when the inversion moved from the warmer East Sea to the colder Yellow Sea, a thermal internal boundary layer (TIBL) gradually formed at the base of the inversion while the sea fog grew in response to cooling and moistening by turbulence mixing; (3) the sea fog developed as the TIBL moved northward and (4) strong northerly cold and dry wind destroyed the TIBL and dissipated the sea fog. The principal findings of this study are that sea fog forms in response to relatively persistent southerly warm/moist wind and a cold sea surface, and that turbulence mixing by wind shear is the primary mechanism for the cooling and moistening the marine layer. In addition, the study of sensitivity experiments indicates that deterministic numerical modeling offers a promising approach to the prediction of sea fog over the Yellow Sea but it may be more efficient to consider ensemble numerical modeling because of the extreme sensitivity to model input.

Diaphragm walling for Sizewell B sets records

International Nuclear Information System (INIS)

Anon.

1988-01-01

The first phase of construction of the Sizewell-B nuclear reactor has been completed. This was the building of a diaphragm wall around the site. It is one of the largest and deepest diaphragm walls to be installed in Europe. The site can be pumped dry of groundwater and the foundations constructed in the dry. The specifications of the wall and its construction, using two Hydrofraise excavation rigs, are described. The excavated material is brought up as a slurry and the (bentonite) slurry is cleaned and desanded. Most of the wall has been formed using a plastic concrete but reinforced concrete has been used for some stretches. The diaphragm wall, which is 1258m long and 55m deep on average, was built in 19 weeks. (U.K.)

Hollow porous-wall glass microspheres for hydrogen storage

Science.gov (United States)

Heung, Leung K.; Schumacher, Ray F.; Wicks, George G.

2010-02-23

A porous wall hollow glass microsphere is provided having a diameter range of between 1 to 200 microns, a density of between 1.0 to 2.0 gm/cc, a porous-wall structure having wall openings defining an average pore size of between 10 to 1000 angstroms, and which contains therein a hydrogen storage material. The porous-wall structure facilitates the introduction of a hydrogen storage material into the interior of the porous wall hollow glass microsphere. In this manner, the resulting hollow glass microsphere can provide a membrane for the selective transport of hydrogen through the porous walls of the microsphere, the small pore size preventing gaseous or liquid contaminants from entering the interior of the hollow glass microsphere.

Imaging of chest wall infections

International Nuclear Information System (INIS)

Chelli Bouaziz, Mouna; Jelassi, Helmi; Chaabane, Skander; Ladeb, Mohamed Fethi; Ben Miled-Mrad, Khaoula

2009-01-01

A wide variety of infections can affect the chest wall including pyogenic, tuberculous, fungal, and some other unusual infections. These potentially life-threatening disorders are frequent especially among immunocompromised patients but often misdiagnosed by physical examination and radiographs. The purpose of this article is to describe the clinical and imaging features of these different chest wall infections according to the different imaging modalities with emphasis on ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI). The outcome of chest wall infection depends on early diagnosis, severity of the immunosuppression, offending organism, and extent of infection. Because clinical findings and laboratory tests may be not contributive in immunocompromised patients, imaging plays an important role in the early detection and precise assessment of the disease. US, CT, and MRI are all useful: bone destruction is more accurately detected with CT whereas soft tissue involvement are better visualized with US and MRI. CT and US are also used to guide percutaneous biopsy and drainage procedures. MR images are helpful in pre-operative planning of extensive chest wall infections. (orig.)

Soft-tissue masses in the abdominal wall

International Nuclear Information System (INIS)

Bashir, U.; Moskovic, E.; Strauss, D.; Hayes, A.; Thway, K.; Pope, R.; Messiou, C.

2014-01-01

Masses involving the abdominal wall arise from a large number of aetiologies. This article will describe a diagnostic approach, imaging features of the most common causes of abdominal wall masses, and highly specific characteristics of less common diseases. A diagnostic algorithm for abdominal wall masses combines clinical history and imaging appearances to classify lesions

Thick domain wall spacetimes with and without reflection symmetry

International Nuclear Information System (INIS)

Melfo, Alejandra; Pantoja, Nelson; Skirzewski, Aureliano

2003-01-01

We show that different thick domain wall spacetimes, for which the scalar field configuration and the potential are the same, can be found as solutions to the coupled Einstein-scalar field equations, depending on whether or not reflection symmetry on the wall is imposed. Spacetimes with reflection symmetry may be dynamic or static, while the asymmetric ones are static. Asymmetric walls are asymptotically flat on one side and reduce to the Taub spacetime on the other. Examples of asymmetric thick walls in D-dimensional spacetimes are given, and previous analysis on the distributional thin-wall limit of the dynamic symmetric thick walls are extended to the asymmetric case. A new family of reflection symmetric, static thick domain wall spacetimes, including previously known Bogomol'nyi-Prasad-Sommerfield walls, is presented

Plasma-wall interactions in RFX

International Nuclear Information System (INIS)

Valisa, M.; Bartiromo, R.; Carraro, L.

1999-01-01

Plasma wall interactions become a crucial issue in the Reversed Field Pinch RFX at high current (>0.7 MA). Wall-Mode Locking (WML) leads to carbon bloom, enhanced recycling and makes the density control very difficult to achieve. Several wall conditioning techniques have improved the capability of controlling recycling, especially boronization with diborane, but at 1 MA of plasma current removal of the WML becomes mandatory. Encouraging results have been achieved by rotating an externally induced perturbation that can unlock the WML. The strong impurity screening mechanism found at intermediate current does not degrade significantly at 1 MA. Modification of the tiles geometry could further reduce the power density dissipation and mitigate the PWI. (author)

Plasma-wall interactions in RFX

International Nuclear Information System (INIS)

Valisa, M.; Bartiromo, R.; Carraro, L.

2001-01-01

Plasma wall interactions become a crucial issue in the Reversed Field Pinch RFX at high current (>0.7 MA). Wall-Mode Locking (WML) leads to carbon bloom, enhanced recycling and makes the density control very difficult to achieve. Several wall conditioning techniques have improved the capability of controlling recycling, especially boronisation with diborane, but at 1 MA of plasma current removal of the WML becomes mandatory. Encouraging results have been achieved by rotating an externally induced perturbation that can unlock the WML. The strong impurity screening mechanism found at intermediate current does not degrade significantly at 1 MA. Modification of the tiles geometry could further reduce the power density dissipation and mitigate the PWI. (author)

Gravitational waves from domain walls and their implications

Directory of Open Access Journals (Sweden)

Kazunori Nakayama

2017-07-01

Full Text Available We evaluate the impact of domain-wall annihilation on the currently ongoing and planned gravitational wave experiments, including a case in which domain walls experience a frictional force due to interactions with the ambient plasma. We show the sensitivity reach in terms of physical parameters, namely, the wall tension and the annihilation temperature. We find that a Higgs portal scalar, which stabilizes the Higgs potential at high energy scales, can form domain walls whose annihilation produces a large amount of gravitational waves within the reach of the advanced LIGO experiment (O5. Domain wall annihilation can also generate baryon asymmetry if the scalar is coupled to either SU(2L gauge fields or the (B−L current. This is a variant of spontaneous baryogenesis, but it naturally avoids the isocurvature constraint due to the scaling behavior of the domain-wall evolution. We delineate the parameter space where the domain-wall baryogenesis works successfully and discuss its implications for the gravitational wave experiments.

Plant cell wall signalling and receptor-like kinases.

Science.gov (United States)

Wolf, Sebastian

2017-02-15

Communication between the extracellular matrix and the cell interior is essential for all organisms as intrinsic and extrinsic cues have to be integrated to co-ordinate development, growth, and behaviour. This applies in particular to plants, the growth and shape of which is governed by deposition and remodelling of the cell wall, a rigid, yet dynamic, extracellular network. It is thus generally assumed that cell wall surveillance pathways exist to monitor the state of the wall and, if needed, elicit compensatory responses such as altered expression of cell wall remodelling and biosynthesis genes. Here, I highlight recent advances in the field of cell wall signalling in plants, with emphasis on the role of plasma membrane receptor-like kinase complexes. In addition, possible roles for cell wall-mediated signalling beyond the maintenance of cell wall integrity are discussed. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

Condensation on a cooled plane upright wall

International Nuclear Information System (INIS)

Fortier, Andre.

1975-01-01

The vapor condensation along a cooled upright plane wall was studied. The theoretical and experimental results obtained in the simple case, give the essential characteristics of the phenomenon of condensation along a cold wall that keeps the vapor apart from the coolant inside a surface condenser. The phenomenon presents two different appearances according as the wall is wetted or not by the liquid. In the first case a continuous liquid film runs down the wall and a conventional Nusselt calculation gives the film thickness and the heat exchange coefficient between a pure saturated vapor and the cold wall. The calculation is developed in detail and the effect of a vapor flow along the film is discussed as well as that of the presence of a noncondensable gas inside the vapor. In the second case, separated liquid drops are formed on the wall, the phenomenon is called ''dropwise condensation'' and the heat exchange coefficients obtained are much higher than with film condensation. The theoretical aspects of the problem are discussed with some experimental results [fr

Analysis of wall-packed-bed thermal interactions

International Nuclear Information System (INIS)

Gorbis, Z.R.; Tillack, M.S.; Tehranian, F.; Abdou, M.A.

1995-01-01

One of the major issues remaining for ceramic breeder blankets involves uncertainties in heat transfer and thermomechanical interactions within the breeder and multiplier regions. Particle bed forms are considered in many reactor blanket designs for both the breeder and Be multiplier. The effective thermal conductivity of beds and the wall-bed thermal conductance are still not adequately characterized, particularly under the influence of mechanical stresses. The problem is particularly serious for the wall conductance between Be and its cladding, where the uncertainty can be greater than 50%. In this work, we describe a new model for the wall-bed conductance that treats the near-wall region as a finite-width zone. The model includes an estimate of the region porosity based on the number of contact points, and the contact area for smooth surfaces. It solves the heat conduction in a near-wall unit cell. The model is verified with existing data and used to predict the range of wall conductances expected in future simulation experiments and in reactor applications. (orig.)

Block survey of wall covered with plant in the city of Tokyo [Japan] and evaluation of thermal environment of wall greening system

International Nuclear Information System (INIS)

Shibuya, K.; Soh, Y.; Satoh, S.

2007-01-01

There were 384 (8877 square m) walls which covered with plant on 10 square km in the city of Tokyo, and the green wall rate in the city of Tokyo was 0.88%. Vines, for example Parthenocissus tricuspidata and Hedera helix, were widely used. The factor of thinking better of the landscape in urban area was one of the easily management of plants. The three wall greening systems, a wall covered with hanging climbers and two types of self-contained living wall, mitigated the thermal environment. However its degree can be depended on the greening method and the greenery occupancy rate of wall

Magnetization reversal in ferromagnetic spirals via domain wall motion

Science.gov (United States)

Schumm, Ryan D.; Kunz, Andrew

2016-11-01

Domain wall dynamics have been investigated in a variety of ferromagnetic nanostructures for potential applications in logic, sensing, and recording. We present a combination of analytic and simulated results describing the reliable field driven motion of a domain wall through the arms of a ferromagnetic spiral nanowire. The spiral geometry is capable of taking advantage of the benefits of both straight and circular wires. Measurements of the in-plane components of the spirals' magnetization can be used to determine the angular location of the domain wall, impacting the magnetoresistive applications dependent on the domain wall location. The spirals' magnetization components are found to depend on the spiral parameters: the initial radius and spacing between spiral arms, along with the domain wall location. The magnetization is independent of the parameters of the rotating field used to move the domain wall, and therefore the model is valid for current induced domain wall motion as well. The speed of the domain wall is found to depend on the frequency of the rotating driving field, and the domain wall speeds can be reliably varied over several orders of magnitude. We further demonstrate a technique capable of injecting multiple domain walls and show the reliable and unidirectional motion of domain walls through the arms of the spiral.

Sea Ice Summer Camp: Bringing Together Arctic Sea Ice Modelers and Observers

Science.gov (United States)

Perovich, D. K.; Holland, M. M.

2016-12-01

The Arctic sea ice has undergone dramatic change and numerical models project this to continue for the foreseeable future. Understanding the mechanisms behind sea ice loss and its consequences for the larger Arctic and global systems is of critical importance if we are to anticipate and plan for the future. One impediment to progress is a disconnect between the observational and modeling communities. A sea ice summer camp was held in Barrow Alaska from 26 May to 1 June 2016 to overcome this impediment and better integrate the sea ice community. The 25 participants were a mix of modelers and observers from 13 different institutions at career stages from graduate student to senior scientist. The summer camp provided an accelerated program on sea ice observations and models and also fostered future collaborative interdisciplinary activities. Each morning was spent in the classroom with a daily lecture on an aspect of modeling or remote sensing followed by practical exercises. Topics included using models to assess sensitivity, to test hypotheses and to explore sources of uncertainty in future Arctic sea ice loss. The afternoons were spent on the ice making observations. There were four observational activities; albedo observations, ice thickness measurements, ice coring and physical properties, and ice morphology surveys. The last field day consisted of a grand challenge where the group formulated a hypothesis, developed an observational and modeling strategy to test the hypothesis, and then integrated the observations and model results. The impacts of changing sea ice are being felt today in Barrow Alaska. We opened a dialog with Barrow community members to further understand these changes. This included an evening discussion with two Barrow sea ice experts and a community presentation of our work in a public lecture at the Inupiat Heritage Center.

Quaternary Sea-ice history in the Arctic Ocean based on a new Ostracode sea-ice proxy

Science.gov (United States)

Cronin, T. M.; Gemery, L.; Briggs, W.M.; Jakobsson, M.; Polyak, L.; Brouwers, E.M.

2010-01-01

Paleo-sea-ice history in the Arctic Ocean was reconstructed using the sea-ice dwelling ostracode Acetabulastoma arcticum from late Quaternary sediments from the Mendeleyev, Lomonosov, and Gakkel Ridges, the Morris Jesup Rise and the Yermak Plateau. Results suggest intermittently high levels of perennial sea ice in the central Arctic Ocean during Marine Isotope Stage (MIS) 3 (25-45 ka), minimal sea ice during the last deglacial (16-11 ka) and early Holocene thermal maximum (11-5 ka) and increasing sea ice during the mid-to-late Holocene (5-0 ka). Sediment core records from the Iceland and Rockall Plateaus show that perennial sea ice existed in these regions only during glacial intervals MIS 2, 4, and 6. These results show that sea ice exhibits complex temporal and spatial variability during different climatic regimes and that the development of modern perennial sea ice may be a relatively recent phenomenon. ?? 2010.

Grain-size based sea-level reconstruction in the south Bohai Sea during the past 135 kyr

Science.gov (United States)

Yi, Liang; Chen, Yanping

2013-04-01

Future anthropogenic sea-level rise and its impact on coastal regions is an important issue facing human civilizations. Due to the short nature of the instrumental record of sea-level change, development of proxies for sea-level change prior to the advent of instrumental records is essential to reconstruct long-term background sea-level changes on local, regional and global scales. Two of the most widely used approaches for past sea-level changes are: (1) exploitation of dated geomorphologic features such as coastal sands (e.g. Mauz and Hassler, 2000), salt marsh (e.g. Madsen et al., 2007), terraces (e.g. Chappell et al., 1996), and other coastal sediments (e.g. Zong et al., 2003); and (2) sea-level transfer functions based on faunal assemblages such as testate amoebae (e.g. Charman et al., 2002), foraminifera (e.g. Chappell and Shackleton, 1986; Horton, 1997), and diatoms (e.g. Horton et al., 2006). While a variety of methods has been developed to reconstruct palaeo-changes in sea level, many regions, including the Bohai Sea, China, still lack detailed relative sea-level curves extending back to the Pleistocene (Yi et al., 2012). For example, coral terraces are absent in the Bohai Sea, and the poor preservation of faunal assemblages makes development of a transfer function for a relative sea-level reconstruction unfeasible. In contrast, frequent alternations between transgression and regression has presumably imprinted sea-level change on the grain size distribution of Bohai Sea sediments, which varies from medium silt to coarse sand during the late Quaternary (IOCAS, 1985). Advantages of grainsize-based relative sea-level transfer function approaches are that they require smaller sample sizes, allowing for replication, faster measurement and higher spatial or temporal resolution at a fraction of the cost of detail micro-palaeontological analysis (Yi et al., 2012). Here, we employ numerical methods to partition sediment grain size using a combined database of

Sea-ice dynamics strongly promote Snowball Earth initiation and destabilize tropical sea-ice margins

Directory of Open Access Journals (Sweden)

A. Voigt

2012-12-01

Full Text Available The Snowball Earth bifurcation, or runaway ice-albedo feedback, is defined for particular boundary conditions by a critical CO₂ and a critical sea-ice cover (SI, both of which are essential for evaluating hypotheses related to Neoproterozoic glaciations. Previous work has shown that the Snowball Earth bifurcation, denoted as (CO₂, SI^*, differs greatly among climate models. Here, we study the effect of bare sea-ice albedo, sea-ice dynamics and ocean heat transport on (CO₂, SI^* in the atmosphere–ocean general circulation model ECHAM5/MPI-OM with Marinoan (~ 635 Ma continents and solar insolation (94% of modern. In its standard setup, ECHAM5/MPI-OM initiates a~Snowball Earth much more easily than other climate models at (CO₂, SI^* ≈ (500 ppm, 55%. Replacing the model's standard bare sea-ice albedo of 0.75 by a much lower value of 0.45, we find (CO₂, SI^* ≈ (204 ppm, 70%. This is consistent with previous work and results from net evaporation and local melting near the sea-ice margin. When we additionally disable sea-ice dynamics, we find that the Snowball Earth bifurcation can be pushed even closer to the equator and occurs at a hundred times lower CO₂: (CO₂, SI^* ≈ (2 ppm, 85%. Therefore, the simulation of sea-ice dynamics in ECHAM5/MPI-OM is a dominant determinant of its high critical CO₂ for Snowball initiation relative to other models. Ocean heat transport has no effect on the critical sea-ice cover and only slightly decreases the critical CO₂. For disabled sea-ice dynamics, the state with 85% sea-ice cover is stabilized by the Jormungand mechanism and shares characteristics with the Jormungand climate states. However, there is no indication of the Jormungand bifurcation and hysteresis in ECHAM5/MPI-OM. The state with 85% sea-ice cover therefore is a soft Snowball state rather than a true

Softenin, a novel protein that softens the connective tissue of sea cucumbers through inhibiting interaction between collagen fibrils.

Directory of Open Access Journals (Sweden)

Yasuhiro Takehana

Full Text Available The dermis in the holothurian body wall is a typical catch connective tissue or mutable collagenous tissue that shows rapid changes in stiffness. Some chemical factors that change the stiffness of the tissue were found in previous studies, but the molecular mechanisms of the changes are not yet fully understood. Detection of factors that change the stiffness by working directly on the extracellular matrix was vital to clarify the mechanisms of the change. We isolated from the body wall of the sea cucumber Stichopus chloronotus a novel protein, softenin, that softened the body-wall dermis. The apparent molecular mass was 20 kDa. The N-terminal sequence of 17 amino acids had low homology to that of known proteins. We performed sequential chemical and physical dissections of the dermis and tested the effects of softenin on each dissection stage by dynamic mechanical tests. Softenin softened Triton-treated dermis whose cells had been disrupted by detergent. The Triton-treated dermis was subjected to repetitive freeze-and-thawing to make Triton-Freeze-Thaw (TFT dermis that was softer than the Triton-treated dermis, implying that some force-bearing structure had been disrupted by this treatment. TFT dermis was stiffened by tensilin, a stiffening protein of sea cucumbers. Softenin softened the tensilin-stiffened TFT dermis while it had no effect on the TFT dermis without tensilin treatment. We isolated collagen from the dermis. When tensilin was applied to the suspending solution of collagen fibrils, they made a large compact aggregate that was dissolved by the application of softenin or by repetitive freeze-and-thawing. These results strongly suggested that softenin decreased dermal stiffness through inhibiting cross-bridge formation between collagen fibrils; the formation was augmented by tensilin and the bridges were broken by the freeze-thaw treatment. Softenin is thus the first softener of catch connective tissue shown to work on the cross

Halo current and resistive wall simulations of ITER

International Nuclear Information System (INIS)

Strauss, H.R.; Zheng Linjin; Kotschenreuther, M.; Park, W.; Jardin, S.; Breslau, J.; Pletzer, A.; Paccagnella, R.; Sugiyama, L.; Chu, M.; Chance, M.; Turnbull, A.

2005-01-01

A number of ITER relevant problems in resistive MHD concern the effects of a resistive wall: vertical displacement events (VDE), halo currents caused by disruptions, and resistive wall modes. Simulations of these events have been carried out using the M3D code. We have verified the growth rate scaling of VDEs, which is proportional to the wall resistivity. Simulations have been done of disruptions caused by large inversion radius internal kink modes, as well as by nonlinear growth of resistive wall modes. Halo current flowing during the disruption has asymmetries with toroidal peaking factor up to about 3. VDEs have larger growth rates during disruption simulations, which may account for the loss of vertical feedback control during disruptions in experiments. Further simulations have been made of disruptions caused by resistive wall modes in ITER equilibria. For these modes the toroidal peaking factor is close to 1. Resistive wall modes in ITER and reactors have also been investigated utilizing the newly developed AEGIS (Adaptive EiGenfunction Independent Solution) linear full MHD code, for realistically shaped, fully toroidal equilibria. The AEGIS code uses an adaptive mesh in the radial direction which allows thin inertial layers to be accurately resolved, such as those responsible for the stabilization of resistive wall modes (RWM) by plasma rotation. Stabilization of resistive wall modes by rotation and wall thickness effects are examined. (author)

The USGS Salton Sea Science Office

Science.gov (United States)

Case, Harvey Lee; Barnum, Douglas A.

2007-01-01

The U.S. Geological Survey's (USGS) Salton Sea Science Office (SSSO) provides scientific information and evaluations to decisionmakers who are engaged in restoration planning and actions associated with the Salton Sea. The primary focus is the natural resources of the Salton Sea, including the sea?s ability to sustain biological resources and associated social and economic values.

XXI century projections of wind-wave conditions and sea-level rise in the Black sea

Science.gov (United States)

Polonsky, A.; Garmashov, A.; Fomin, V.; Valchev, N.; Trifonova, E.

2012-04-01

Projection of regional climate changes for XXI century is one of the priorities of EC environmental programme. Potential worsening of the waves' statistics, sea level rise and extreme surges are the principal negative consequences of the climate change for marine environment. That is why the main purpose of this presentation is to discuss the above issue for the Black sea region (with a strong focus to the south-west subregion because the maximum heights of waves exceeding 10 m occur just here) using output of several global coupled models (GCM) for XXI century, wave simulation, long-term observations of sea level and statistical techniques. First of all we tried to choose the best coupled model (s) simulated the Black sea climate change and variability using the control experiments for 20 century (203). The principal result is as follows. There is not one model which is simulating adequately even one atmospheric parameter for all seasons. Therefore we considered (for the climate projection) different outputs form various models. When it was possible we calculated also the ensemble mean projection for the selected model (s) and emission scenarios. To calculate the wave projection we used the output of SWAN model forced by the GCM wind projection for 2010 to 2100. To estimate the sea level rise in XXI century and future surges statistics we extrapolate the observed sea level rise tendencies, statistical relation between wave heights and sea level and wave scenarios. Results show that in general, the climate change in XXI century doesn't lead to the catastrophic change of the Black sea wind-wave statistics including the extreme waves in the S-W Black sea. The typical atmospheric pattern leading to the intense storm in the S-W Black sea is characterized by the persistent anticyclonic area to the North of the Black sea and cyclonic conditions in the Southern Black sea region. Such pressure pattern causes persistent and strong eastern or north-eastern wind which

The future for the Global Sea Level Observing System (GLOSS) Sea Level Data Rescue

Science.gov (United States)

Bradshaw, Elizabeth; Matthews, Andrew; Rickards, Lesley; Aarup, Thorkild

2016-04-01

Historical sea level data are rare and unrepeatable measurements with a number of applications in climate studies (sea level rise), oceanography (ocean currents, tides, surges), geodesy (national datum), geophysics and geology (coastal land movements) and other disciplines. However, long-term time series are concentrated in the northern hemisphere and there are no records at the Permanent Service for Mean Sea Level (PSMSL) global data bank longer than 100 years in the Arctic, Africa, South America or Antarctica. Data archaeology activities will help fill in the gaps in the global dataset and improve global sea level reconstruction. The Global Sea Level Observing System (GLOSS) is an international programme conducted under the auspices of the WMO-IOC Joint Technical Commission for Oceanography and Marine Meteorology. It was set up in 1985 to collect long-term tide gauge observations and to develop systems and standards "for ocean monitoring and flood warning purposes". At the GLOSS-GE-XIV Meeting in 2015, GLOSS agreed on a number of action items to be developed in the next two years. These were: 1. To explore mareogram digitisation applications, including NUNIEAU (more information available at: http://www.mediterranee.cerema.fr/logiciel-de-numerisation-des-enregistrements-r57.html) and other recent developments in scanning/digitisation software, such as IEDRO's Weather Wizards program, to see if they could be used via a browser. 2. To publicise sea level data archaeology and rescue by: • maintaining and regularly updating the Sea Level Data Archaeology page on the GLOSS website • strengthening links to the GLOSS data centres and data rescue organisations e.g. linking to IEDRO, ACRE, RDA • restarting the sea level data rescue blog with monthly posts. 3. Investigate sources of funding for data archaeology and rescue projects. 4. Propose "Guidelines" for rescuing sea level data. These action items will aid the discovery, scanning, digitising and quality control

The dorsal shell wall structure of Mesozoic ammonoids

Directory of Open Access Journals (Sweden)

Gregor Radtke

2017-03-01

Full Text Available The study of pristine preserved shells of Mesozoic Ammonoidea shows different types of construction and formation of the dorsal shell wall. We observe three major types: (i The vast majority of Ammonoidea, usually planispirally coiled, has a prismatic reduced dorsal shell wall which consists of an outer organic component (e.g., wrinkle layer, which is the first layer to be formed, and the subsequently formed dorsal inner prismatic layer. The dorsal mantle tissue suppresses the formation of the outer prismatic layer and nacreous layer. With the exception of the outer organic component, secretion of a shell wall is omitted at the aperture. A prismatic reduced dorsal shell wall is always secreted immediately after the hatching during early teleoconch formation. Due to its broad distribution in (planispiral Ammonoidea, the prismatic reduced dorsal shell wall is probably the general state. (ii Some planispirally coiled Ammonoidea have a nacreous reduced dorsal shell wall which consists of three mineralized layers: two prismatic layers (primary and secondary dorsal inner prismatic layer and an enclosed nacreous layer (secondary dorsal nacreous layer. The dorsal shell wall is omitted at the aperture and was secreted in the rear living chamber. Its layers are a continuation of an umbilical shell doubling (reinforcement by additional shell layers that extends towards the ventral crest of the preceding whorl. The nacreous reduced dorsal shell wall is formed in the process of ontogeny following a prismatic reduced dorsal shell wall. (iii Heteromorph and some planispirally coiled taxa secrete a complete dorsal shell wall which forms a continuation of the ventral and lateral shell layers. It is formed during ontogeny following a prismatic reduced dorsal shell wall or a priori. The construction is identical with the ventral and lateral shell wall, including a dorsal nacreous layer. The wide distribution of the ability to form dorsal nacre indicates that it is

Effect of Wall Friction and Vortex Generation on Radial Void Distribution The Wall - Vortex Effect

Energy Technology Data Exchange (ETDEWEB)

Rouhani, Zia

1974-09-15

Arguments are presented to prove the existence of rolling vortices in two-phase flow. In liquid phase they will appear in a boundary layer near the walls while in the continuous vapor phase they will occur near the interface with a liquid film. The intensity and size of these vortices are expected to depend on the local velocity gradients normal to the walls. A discussion is given of the interaction between the rotational field associated with such vortices and bubbles in liquid flow or droplets in vapor-flow. This interaction is called the wall-vortex effect. It appears that several, apparently unrelated, phenomena observed in two-phase flow systems may be interpreted in terms of this mechanism. Among these are: Radial void peaking near the walls; Slip ratios less than unity observed even in vertical upward flow; Reduced droplet diffusion near the liquid film; Reduced vapor mixing between subchannels at low steam qualities; and Accelerated flashing process in flow of depressurized liquid. Finally, a comparison with the well-known Magnus effect is also included

Autolysis and extension of isolated walls from growing cucumber hypocotyls

Science.gov (United States)

Cosgrove, D. J.; Durachko, D. M.

1994-01-01

Walls isolated from cucumber hypocotyls retain autolytic activities and the ability to extend when placed under the appropriate conditions. To test whether autolysis and extension are related, we treated the walls in various ways to enhance or inhibit long-term wall extension ('creep') and measured autolysis as release of various saccharides from the wall. Except for some non-specific inhibitors of enzymatic activity, we found no correlation between wall extension and wall autolysis. Most notably, autolysis and extension differed strongly in their pH dependence. We also found that exogenous cellulases and pectinases enhanced extension in native walls, but when applied to walls previously inactivated with heat or protease these enzymes caused breakage without sustained extension. In contrast, pretreatment of walls with pectinase or cellulase, followed by boiling in methanol to inactivate the enzymes, resulted in walls with much stronger expansin-mediated extension responses. Crude protein preparations from the digestive tracts of snails enhanced extension of both native and inactivated walls, and these preparations contained expansin-like proteins (assessed by Western blotting). Our results indicate that the extension of isolated cucumber walls does not depend directly on the activity of endogenous wall-bound autolytic enzymes. The results with exogenous enzymes suggest that the hydrolysis of matrix polysaccharides may not induce wall creep by itself, but may act synergistically with expansins to enhance wall extension.

Temporal variability in SeaWiFS derived apparent optical properties in European seas

Science.gov (United States)

Vantrepotte, V.; Mélin, F.

2010-02-01

The 10-year record of ocean color data provided by the SeaWiFS mission is an important asset for monitoring and research activities conducted on the optically complex European seas. This study makes use of the SeaWiFS data set of normalized water leaving radiances LWN to study the major characteristics of temporal variability associated with optical properties across the entire European domain. Specifically, the time series of LWN and associated band ratios are decomposed into terms representing a fixed seasonal cycle, irregular variations and trends, and the contribution of these components to the total variance is described for the various basins. The diversity of the European waters is fully reflected by the range of results varying with regions and wavelengths. Generally, the Mediterranean and Baltic seas appear as two end-members with, respectively, high and low contributions of the seasonal component to the total variance. The existence of linear trends affecting the satellite products is also explored for each basin. By focusing the analysis on LWN and band ratios, the validity of the results is not limited by the varying levels of uncertainty that characterize derived products such as the concentration of chlorophyll a in optically complex waters. Statistically significant, and in some cases large, trends are detected in the Atlantic Ocean west of the European western shelf, the central North Sea, the English Channel, the Black Sea, the northern Adriatic, and various regions of the Mediterranean Sea and the northern Baltic Sea, revealing changes in the concentrations of optically significant constituents in these regions.

The Influence of Wind and Basin Eddies in Controlling Sea Level Variations in the Coastal Red Sea

KAUST Repository

Abualnaja, Yasser

2015-04-01

Sea level variations in the central Red Sea coastal zone span a range of roughly 1.2 m. Though relatively small, these water level changes can significantly impact the environment over the shallow reef tops prevalent in the central Red Sea, altering the water depth by a factor or two or more. Roughly half of the coastal sea level variance in central Red Sea is due to elevation changes in an \\'intermediate\\' frequency band, with periods between 2 days and 1 month. We examined the sea level signal in this band using the data from pressure sensors maintained for more than five years at a number of locations in Saudi Arabian coastal waters between 20.1 and 23.5 oN. We find that the intermediate-band sea level variations are strongly correlated with the local wind stress measured at a meteorological buoy. The maximum pressure-wind correlation occurs at wind direction closely aligned with the alongshore orientation and at a lag (wind leading) of 45 hr, which is consistent with the expected response of the coastal sea level to local wind forcing. However, less than half of the sea level variance in the intermediate band is related, through linear correlation, with local wind forcing. Our analysis indicates that the residual coastal sea level signal, not associated with wind forcing, is largely driven remotely by the passage of mesoscale eddies, revealed by satellite altimeter-derived sea level anomaly fields of the central Red Sea. These eddy-driven coastal sea level changes occur on time scales of 10-30 days. They span a range of 0.5 m, and thus constitute an import component of the sea level signal in the coastal Red Sea.

The Influence of Wind and Basin Eddies in Controlling Sea Level Variations in the Coastal Red Sea

KAUST Repository

Abualnaja, Yasser; Churchill, James H.; Nellayaputhenpeedika, Mohammedali; Limeburner, Richard

2015-01-01

Sea level variations in the central Red Sea coastal zone span a range of roughly 1.2 m. Though relatively small, these water level changes can significantly impact the environment over the shallow reef tops prevalent in the central Red Sea, altering the water depth by a factor or two or more. Roughly half of the coastal sea level variance in central Red Sea is due to elevation changes in an 'intermediate' frequency band, with periods between 2 days and 1 month. We examined the sea level signal in this band using the data from pressure sensors maintained for more than five years at a number of locations in Saudi Arabian coastal waters between 20.1 and 23.5 oN. We find that the intermediate-band sea level variations are strongly correlated with the local wind stress measured at a meteorological buoy. The maximum pressure-wind correlation occurs at wind direction closely aligned with the alongshore orientation and at a lag (wind leading) of 45 hr, which is consistent with the expected response of the coastal sea level to local wind forcing. However, less than half of the sea level variance in the intermediate band is related, through linear correlation, with local wind forcing. Our analysis indicates that the residual coastal sea level signal, not associated with wind forcing, is largely driven remotely by the passage of mesoscale eddies, revealed by satellite altimeter-derived sea level anomaly fields of the central Red Sea. These eddy-driven coastal sea level changes occur on time scales of 10-30 days. They span a range of 0.5 m, and thus constitute an import component of the sea level signal in the coastal Red Sea.

The Red Sea: An Arena for Wind-Wave Modeling in Enclosed Seas

KAUST Repository

Langodan, Sabique

2016-12-01

Wind and waves play a major role in important ocean dynamical processes, such as the exchange of heat, momentum and gases between atmosphere and ocean, that greatly contributes to the earth climate and marine lives. Knowledge on wind and wave weather and climate is crucial for a wide range of applications, including oceanographic studies, maritime activities and ocean engineering. Despite being one of the important world shipping routes, the wind-wave characteristics in the Red Sea are yet to be fully explored. Because of the scarcity of waves data in the Red Sea, numerical models become crucial and provide very powerful tools to extrapolate wind and wave data in space, and backward and forward in time. Unlike open oceans, enclosed basins wave have different characteristics, mainly because of their local generation processes. The complex orography on both sides of the Red Sea makes the local wind, and consequently wave, modeling very challenging. This thesis considers the modeling of wind-wave characteristics in the Red Sea, including their climate variability and trends using state-of-the-art numerical models and all available observations. Different approaches are investigated to model and understand the general and unusual wind and wave conditions in the basin using standard global meteorological products and customised regional wind and wave models. After studying and identifying the main characteristics of the wind-wave variability in the Red Sea, we demonstrate the importance of generating accurate atmospheric forcing through data assimilation for reliable wave simulations. In particular, we show that the state-of-the-art physical formulation of wave models is not suitable to model the unique situation of the two opposing wind-waves systems in the Red Sea Convergence Zone, and propose and successfully test a modification to the input and white-capping source functions to address this problem. We further investigate the climate variability and trends of wind

Estimating the effective nitrogen import: An example for the North Sea-Baltic Sea boundary

Science.gov (United States)

Radtke, H.; Maar, M.

2016-10-01

Semienclosed water bodies such as the Baltic Sea are prone to eutrophication problems. If local nutrient abatement measures are taken to tackle these problems, their success may be limited if a strong nutrient exchange with the adjacent waters exists. The quantification of this exchange is therefore essential to estimate its impact on the ecosystem status. At the example of the Baltic Sea and the North Sea, we illustrate that neither gross transports nor net transports of nutrients have a strong informative value in this context. Instead, we define an "effective import" as the import of nutrients which have not been inside the Baltic Sea before and estimate it in an ecological model with a nutrient-tagging technique. This effective import of bioreactive nitrogen from the Skagerrak to the Kattegat amounts to 103 kt/yr; from Kattegat to Belt Sea it is 54 kt/yr. The nitrogen exchange is therefore 30% stronger than other estimates, e.g., based on import in the deep water, suggest. An isolated view on the Baltic Sea and the North Sea in terms of eutrophication, as it is practiced in management today, is therefore questionable. Nitrogen imported from the North Sea typically spreads eastward up to the Bornholm Basin but can be transported into the deep waters of the Gotland Basin during Major Baltic Inflows in a significant amount.

Sublacustrine river valley in the shelf zone of the Black Sea parallel to the Bulgarian coast

Science.gov (United States)

Preisinger, A.; Aslanian, S.; Beigelbeck, R.; Heinitz, W.-D.

2009-04-01

The considered sublacustrine river valley is situated in the shelf zone of the Black Sea. It runs in parallel to the Bulgarian coast, was formed in the time period of the Younger Dryas (Preisinger et al., 2005), and features an inclination of about 0.5 m/km. An about 200 km long sediment wall separates the approximately 10 km broad river valley from the outside shelf zone. This wall was generated during the Older Dryas until the beginning of the Younger Dryas. Its shape was formed by transportation of water and sediment from the Strait of Kerch by a circulating rim current in the Black Sea and water as well as sediment flow of the Danube in direction to the Bosporus. New investigations of the sediments of this river valley were performed by utilizing a Sediment Echo Sounder (SES 2000). This Echo Sounder is a parametric sub-bottom profiler enabling a high resolution sub-bottom analyses. It is capable of penetrating sea beds up to more than 50 m of water depth. The received echo data are real-time processed. The signal amplitudes are valuated in context to a logarithmic scale and graphically visualized by means of a colorized echogram utilizing false colours ranging from red for a high to blue representing a low signal (W.-D. Heinitz et al., 1998). The highest signal (red) is given by the acoustic impedance of the boundary between sea water and river sediment. The echograms of the river valley depict spatially isolated (red) high-signal peaks, which are periodically repeated in vertical direction between the sediment surface and the bottom of the valley. The number of these high-signal parts increase with an increasing valley depth. Studying of the distribution of these peaks allows to draw conclusions regarding the content and composition of the sediment. This prediction of the sediment composition obtained by means of the SES 2000 was successfully verified by analyzing a gravity core taken near Nos Maslen (at 44 m water depth) with a particular focus on the water

Fermentation of the endosperm cell walls of monocotyledon and dicotyledon plant species: The relationship between cell wall characteristics and fermentability

NARCIS (Netherlands)

Laar, van H.; Tamminga, S.; Williams, B.A.; Verstegen, M.W.A.

2000-01-01

Cell walls from the endosperm of four monocotyledons (maize, wheat, rye, and rice) and four dicotyledons (soya bean, lupin, faba bean, and pea) seeds were studied to relate cell wall composition and structure with fermentation characteristics. Cell wall material was isolated from the endosperm of

Daytime sea fog retrieval based on GOCI data: a case study over the Yellow Sea.

Science.gov (United States)

Yuan, Yibo; Qiu, Zhongfeng; Sun, Deyong; Wang, Shengqiang; Yue, Xiaoyuan

2016-01-25

In this paper, a new daytime sea fog detection algorithm has been developed by using Geostationary Ocean Color Imager (GOCI) data. Based on spectral analysis, differences in spectral characteristics were found over different underlying surfaces, which include land, sea, middle/high level clouds, stratus clouds and sea fog. Statistical analysis showed that the Rrc (412 nm) (Rayleigh Corrected Reflectance) of sea fog pixels is approximately 0.1-0.6. Similarly, various band combinations could be used to separate different surfaces. Therefore, three indices (SLDI, MCDI and BSI) were set to discern land/sea, middle/high level clouds and fog/stratus clouds, respectively, from which it was generally easy to extract fog pixels. The remote sensing algorithm was verified using coastal sounding data, which demonstrated that the algorithm had the ability to detect sea fog. The algorithm was then used to monitor an 8-hour sea fog event and the results were consistent with observational data from buoys data deployed near the Sheyang coast (121°E, 34°N). The goal of this study was to establish a daytime sea fog detection algorithm based on GOCI data, which shows promise for detecting fog separately from stratus.

The potential role of sea spray droplets in facilitating air-sea gas transfer

Science.gov (United States)

Andreas, E. L.; Vlahos, P.; Monahan, E. C.

2016-05-01

For over 30 years, air-sea interaction specialists have been evaluating and parameterizing the role of whitecap bubbles in air-sea gas exchange. To our knowledge, no one, however, has studied the mirror image process of whether sea spray droplets can facilitate air-sea gas exchange. We are therefore using theory, data analysis, and numerical modeling to quantify the role of spray on air-sea gas transfer. In this, our first formal work on this subject, we seek the rate-limiting step in spray-mediated gas transfer by evaluating the three time scales that govern the exchange: τ air , which quantifies the rate of transfer between the atmospheric gas reservoir and the surface of the droplet; τ int , which quantifies the exchange rate across the air-droplet interface; and τ aq , which quantifies gas mixing within the aqueous solution droplet.

Two endogenous proteins that induce cell wall extension in plants

Science.gov (United States)

McQueen-Mason, S.; Durachko, D. M.; Cosgrove, D. J.

1992-01-01

Plant cell enlargement is regulated by wall relaxation and yielding, which is thought to be catalyzed by elusive "wall-loosening" enzymes. By employing a reconstitution approach, we found that a crude protein extract from the cell walls of growing cucumber seedlings possessed the ability to induce the extension of isolated cell walls. This activity was restricted to the growing region of the stem and could induce the extension of isolated cell walls from various dicot stems and the leaves of amaryllidaceous monocots, but was less effective on grass coleoptile walls. Endogenous and reconstituted wall extension activities showed similar sensitivities to pH, metal ions, thiol reducing agents, proteases, and boiling in methanol or water. Sequential HPLC fractionation of the active wall extract revealed two proteins with molecular masses of 29 and 30 kD associated with the activity. Each protein, by itself, could induce wall extension without detectable hydrolytic breakdown of the wall. These proteins appear to mediate "acid growth" responses of isolated walls and may catalyze plant cell wall extension by a novel biochemical mechanism.

The White Sea, Russia

Science.gov (United States)

2002-01-01

Editor's Note: The caption below, published on May 10, 2001, is incorrect. According to Masha Vorontsova, director of the International Fund for Animal Welfare in Moscow, the situation with the seal pups in the White Sea is normal. There is no disaster and there never was. For more details, refer to the article entitled 'No Danger' on the New Scientist home page. The Earth Observatory regrets the earlier errant report. Original Caption According to the Russian Polar Research Institute for Fisheries and Oceanography, between 250,000 and 300,000 Greenland seal pups face death by starvation over the next two months due to a cruel trick by mother nature. The seals, most of them less than two months old, are trapped on ice sheets that remain locked in the White Sea, located near Archangel in Northern Russia. Typically, during the spring thaw the ice sheets break up and flow with the currents northward into the Barents Sea, the seals' spring feeding grounds. The seal pups hitch a ride on the ice floes, living on their own individual stores of fat until they arrive in the Barents Sea. Their mothers departed for the Barents Sea weeks ago. In a normal year, the seal pups' trip from the White Sea out to the Barents takes about six weeks and the seals have adapted to rely upon this mechanism of mother nature. During their yearly migration, the mother seals usually stay with their pups and feed them until their pelts turn from white to grey--a sign that the pups are mature enough to swim and feed themselves. Unfortunately, this year unusually strong northerly winds created a bottleneck of ice near the mouth of the white sea, thus blocking the flow of ice and trapping the pups. These true-color images of the White Sea were acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. This image, taken May 2, 2000 that there is usually much less ice in the White Sea this time of year as most of it is typically en route to the

Energy efficient residential house wall system

International Nuclear Information System (INIS)

Aldawi, Fayez; Date, Abhijit; Alam, Firoz; Khan, Iftekhar; Alghamdi, Mohammed

2013-01-01

The energy consumption and greenhouse gas emission by the residential housing sector are considered to be one of the largest in economically developed countries. The larger energy consumption and greenhouse gas emission not only put additional pressure on finite fossil fuel resources but also cause global warming and climate change. Additionally, the residential housing sector will be consuming more energy as the house demand and average house floor area are progressively increasing. With currently used residential house wall systems, it is hard to reduce energy consumption for ongoing house space heating and cooling. A smart house wall envelope with optimal thermal masses and insulation materials is vital for reducing our increasing energy consumption. The major aim of this study is to investigate thermal performance and energy saving potential of a new house wall system for variable climate conditions. The thermal performance modelling was carried out using commercially developed software AccuRate ® . The findings indicate that a notable energy savings can be accomplished if a smart house wall system is used. -- Highlights: • Smart house wall system. • Thermal performance modelling and star energy rating. • Energy savings and greenhouse gas reduction

Sea Ice Ecosystems

Science.gov (United States)

Arrigo, Kevin R.

2014-01-01

Polar sea ice is one of the largest ecosystems on Earth. The liquid brine fraction of the ice matrix is home to a diverse array of organisms, ranging from tiny archaea to larger fish and invertebrates. These organisms can tolerate high brine salinity and low temperature but do best when conditions are milder. Thriving ice algal communities, generally dominated by diatoms, live at the ice/water interface and in recently flooded surface and interior layers, especially during spring, when temperatures begin to rise. Although protists dominate the sea ice biomass, heterotrophic bacteria are also abundant. The sea ice ecosystem provides food for a host of animals, with crustaceans being the most conspicuous. Uneaten organic matter from the ice sinks through the water column and feeds benthic ecosystems. As sea ice extent declines, ice algae likely contribute a shrinking fraction of the total amount of organic matter produced in polar waters.

The SeaDAS Processing and Analysis System: SeaWiFS, MODIS, and Beyond

Science.gov (United States)

MacDonald, M. D.; Ruebens, M.; Wang, L.; Franz, B. A.

2005-12-01

The SeaWiFS Data Analysis System (SeaDAS) is a comprehensive software package for the processing, display, and analysis of ocean data from a variety of satellite sensors. Continuous development and user support by programmers and scientists for more than a decade has helped to make SeaDAS the most widely used software package in the world for ocean color applications, with a growing base of users from the land and sea surface temperature community. Full processing support for past (CZCS, OCTS, MOS) and present (SeaWiFS, MODIS) sensors, and anticipated support for future missions such as NPP/VIIRS, enables end users to reproduce the standard ocean archive product suite distributed by NASA's Ocean Biology Processing Group (OBPG), as well as a variety of evaluation and intermediate ocean, land, and atmospheric products. Availability of the processing algorithm source codes and a software build environment also provide users with the tools to implement custom algorithms. Recent SeaDAS enhancements include synchronization of MODIS processing with the latest code and calibration updates from the MODIS Calibration Support Team (MCST), support for all levels of MODIS processing including Direct Broadcast, a port to the Macintosh OS X operating system, release of the display/analysis-only SeaDAS-Lite, and an extremely active web-based user support forum.