Derivation of intermediate to silicic magma from the basalt analyzed at the Vega 2 landing site, Venus

PubMed Central

2018-01-01

Geochemical modeling using the basalt composition analyzed at the Vega 2 landing site indicates that intermediate to silicic liquids can be generated by fractional crystallization and equilibrium partial melting. Fractional crystallization modeling using variable pressures (0.01 GPa to 0.5 GPa) and relative oxidation states (FMQ 0 and FMQ -1) of either a wet (H2O = 0.5 wt%) or dry (H2O = 0 wt%) parental magma can yield silicic (SiO2 > 60 wt%) compositions that are similar to terrestrial ferroan rhyolite. Hydrous (H2O = 0.5 wt%) partial melting can yield intermediate (trachyandesite to andesite) to silicic (trachydacite) compositions at all pressures but requires relatively high temperatures (≥ 950°C) to generate the initial melt at intermediate to low pressure whereas at high pressure (0.5 GPa) the first melts will be generated at much lower temperatures (< 800°C). Anhydrous partial melt modeling yielded mafic (basaltic andesite) and alkaline compositions (trachybasalt) but the temperature required to produce the first liquid is very high (≥ 1130°C). Consequently, anhydrous partial melting is an unlikely process to generate derivative liquids. The modeling results indicate that, under certain conditions, the Vega 2 composition can generate silicic liquids that produce granitic and rhyolitic rocks. The implication is that silicic igneous rocks may form a small but important component of the northeast Aphrodite Terra. PMID:29584745

Co(salophen)-Catalyzed Aerobic Oxidation of p-Hydroquinone: Mechanism and Implications for Aerobic Oxidation Catalysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anson, Colin W.; Ghosh, Soumya; Hammes-Schiffer, Sharon

2016-03-30

Macrocyclic metal complexes and p-benzoquinones are commonly used as co-catalytic redox mediators in aerobic oxidation reactions. In an effort to gain insight into the mechanism and energetic efficiency of these reactions, we investigated Co(salophen)-catalyzed aerobic oxidation of p-hydroquinone. Kinetic and spectroscopic data suggest that the catalyst resting-state consists of an equilibrium between a CoII(salophen) complex, a CoIII-superoxide adduct, and a hydrogen-bonded adduct between the hydroquinone and the CoIII–O2 species. The kinetic data, together with density functional theory data, suggest that the turnover-limiting step features proton-coupled electron transfer from a semi-hydroquinone species and a CoIII-hydroperoxide intermediate. Additional experimental and computational datamore » suggest that a coordinated H2O2 intermediate oxidizes a second equivalent of hydroquinone. This research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center, funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. The NSF provided partial support for the EPR instrumentation (NSF CHE-0741901).« less

The equilibrium properties and folding kinetics of an all-atom Go model of the Trp-cage.

PubMed

Linhananta, Apichart; Boer, Jesse; MacKay, Ian

2005-03-15

The ultrafast-folding 20-residue Trp-cage protein is quickly becoming a new benchmark for molecular dynamics studies. Already several all-atom simulations have probed its equilibrium and kinetic properties. In this work an all-atom Go model is used to accurately represent the side-chain packing and native atomic contacts of the Trp-cage. The model reproduces the hallmark thermodynamics cooperativity of small proteins. Folding simulations observe that in the fast-folding dominant pathway, partial alpha-helical structure forms before hydrophobic core collapse. In the slow-folding secondary pathway, partial core collapse occurs before helical structure. The slow-folding rate of the secondary pathway is attributed to the loss of side-chain rotational freedom, due to the early core collapse, which impedes the helix formation. A major finding is the observation of a low-temperature kinetic intermediate stabilized by a salt bridge between residues Asp-9 and Arg-16. Similar observations [R. Zhou, Proc. Natl. Acad. Sci. U.S.A. 100, 13280 (2003)] were reported in a recent study using an all-atom model of the Trp-cage in explicit water, in which the salt-bridge stabilized intermediate was hypothesized to be the origin of the ultrafast-folding mechanism. A theoretical mutation that eliminates the Asp-9-Arg-16 salt bridge, but leaves the residues intact, is performed. Folding simulations of the mutant Trp-cage observe a two-state free-energy landscape with no kinetic intermediate and a significant decrease in the folding rate, in support of the hypothesis.

The equilibrium properties and folding kinetics of an all-atom Go xAF model of the Trp-cage

NASA Astrophysics Data System (ADS)

Linhananta, Apichart; Boer, Jesse; MacKay, Ian

2005-03-01

The ultrafast-folding 20-residue Trp-cage protein is quickly becoming a new benchmark for molecular dynamics studies. Already several all-atom simulations have probed its equilibrium and kinetic properties. In this work an all-atom Go ¯ model is used to accurately represent the side-chain packing and native atomic contacts of the Trp-cage. The model reproduces the hallmark thermodynamics cooperativity of small proteins. Folding simulations observe that in the fast-folding dominant pathway, partial α-helical structure forms before hydrophobic core collapse. In the slow-folding secondary pathway, partial core collapse occurs before helical structure. The slow-folding rate of the secondary pathway is attributed to the loss of side-chain rotational freedom, due to the early core collapse, which impedes the helix formation. A major finding is the observation of a low-temperature kinetic intermediate stabilized by a salt bridge between residues Asp-9 and Arg-16. Similar observations [R. Zhou, Proc. Natl. Acad. Sci. U.S.A. 100, 13280 (2003)] were reported in a recent study using an all-atom model of the Trp-cage in explicit water, in which the salt-bridge stabilized intermediate was hypothesized to be the origin of the ultrafast-folding mechanism. A theoretical mutation that eliminates the Asp-9-Arg-16 salt bridge, but leaves the residues intact, is performed. Folding simulations of the mutant Trp-cage observe a two-state free-energy landscape with no kinetic intermediate and a significant decrease in the folding rate, in support of the hypothesis.

Density function theoretical study on the complex involved in Th atom-activated C-C bond in C2H6

NASA Astrophysics Data System (ADS)

Qing-Qing, Wang; Peng, Li; Tao, Gao; Hong-Yan, Wang; Bing-Yun, Ao

2016-06-01

Density functional theory (DFT) calculations are performed to investigate the reactivity of Th atom toward ethane C-C bond activation. A comprehensive description of the reaction mechanisms leading to two different reaction products is presented. We report a complete exploration of the potential energy surfaces by taking into consideration different spin states. In addition, the intermediate and transition states along the reaction paths are characterized. Total, partial, and overlap population density of state diagrams and analyses are also presented. Furthermore, the natures of the chemical bonding of intermediate and transition states are studied by using topological method combined with electron localization function (ELF) and Mayer bond order. Infrared spectrum (IR) is obtained and further discussed based on the optimized geometries. Project supported by the National Natural Science Foundation of China (Grant Nos. 21371160, 21401173, and 11364023).

Partial to complete wetting transitions in immiscible ternary blends with PLA: the influence of interfacial confinement.

PubMed

Zolali, Ali M; Favis, Basil D

2017-04-12

In this study it is shown that the three different intermediate phases in melt blended ternary PLA/PHBV/PBS, PLA/PBAT/PE and PLA/PE/PBAT systems all demonstrate partial wetting, but have very different wetting behaviors as a function of composition and annealing. The interfacial tension of the various components, their spreading coefficients and the contact angles of the confined partially wet droplets at the interface are examined in detail. A wetting transition from partially wet droplets to a complete layer at the interface is observed for both PHBV and PBAT by increasing the concentration and also by annealing. In contrast, in PLA/PE/PBAT, the partially wet droplets of PE at the interface of PLA/PBAT coalesce and grow in size, but remain partially wet even at a high PE concentration of 20% and after 30 min of quiescent annealing. The dewetting speed of the intermediate phase is found to be the principal factor controlling these wetting transitions. This work shows the significant potential for controlled wetting and structuring in ternary polymer systems.

Mechanism of IAPP amyloid fibril formation involves an intermediate with a transient β-sheet

PubMed Central

Buchanan, Lauren E.; Dunkelberger, Emily B.; Tran, Huong Q.; Cheng, Pin-Nan; Chiu, Chi-Cheng; Cao, Ping; Raleigh, Daniel P.; de Pablo, Juan J.; Nowick, James S.; Zanni, Martin T.

2013-01-01

Amyloid formation is implicated in more than 20 human diseases, yet the mechanism by which fibrils form is not well understood. We use 2D infrared spectroscopy and isotope labeling to monitor the kinetics of fibril formation by human islet amyloid polypeptide (hIAPP or amylin) that is associated with type 2 diabetes. We find that an oligomeric intermediate forms during the lag phase with parallel β-sheet structure in a region that is ultimately a partially disordered loop in the fibril. We confirm the presence of this intermediate, using a set of homologous macrocyclic peptides designed to recognize β-sheets. Mutations and molecular dynamics simulations indicate that the intermediate is on pathway. Disrupting the oligomeric β-sheet to form the partially disordered loop of the fibrils creates a free energy barrier that is the origin of the lag phase during aggregation. These results help rationalize a wide range of previous fragment and mutation studies including mutations in other species that prevent the formation of amyloid plaques. PMID:24218609

15. DETAIL VIEW OF MAIN LOCK MITER GATE IN PARTIALLY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. DETAIL VIEW OF MAIN LOCK MITER GATE IN PARTIALLY OPENED POSITION, LOOKING NORTHWEST (UPSTREAM). COMPRESSOR BUILDING VISIBLE TO REAR ON INTERMEDIATE WALL - Upper Mississippi River 9-Foot Channel Project, Lock & Dam 27, Granite City, Madison County, IL

Multi-hop teleportation based on W state and EPR pairs

NASA Astrophysics Data System (ADS)

Hai-Tao, Zhan; Xu-Tao, Yu; Pei-Ying, Xiong; Zai-Chen, Zhang

2016-05-01

Multi-hop teleportation has significant value due to long-distance delivery of quantum information. Many studies about multi-hop teleportation are based on Bell pairs, partially entangled pairs or W state. The possibility of multi-hop teleportation constituted by partially entangled pairs relates to the number of nodes. The possibility of multi-hop teleportation constituted by double W states is after n-hop teleportation. In this paper, a multi-hop teleportation scheme based on W state and EPR pairs is presented and proved. The successful possibility of quantum information transmitted hop by hop through intermediate nodes is deduced. The possibility of successful transmission is after n-hop teleportation. Project supported by the National Natural Science Foundation of China (Grant No. 61571105), the Prospective Future Network Project of Jiangsu Province, China (Grant No. BY2013095-1-18), and the Independent Project of State Key Laboratory of Millimeter Waves, China (Grant No. Z201504).

Contemporary Cambodian: The Social Institutions.

ERIC Educational Resources Information Center

Kheang, Lim Hack; And Others

"Contemporary Cambodian" consists of seven parts: the "Grammatical Sketch," the "Introduction," four intermediate modules, and a Cambodian-English glossary containing all the words in the series. After completing the "Introduction," a student can study the intermediate modules in any order, since each serves as a partial review of the others. This…

Catalyst containing oxygen transport membrane

DOEpatents

Christie, Gervase Maxwell; Wilson, Jamie Robyn; van Hassel, Bart Antonie

2012-12-04

A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a high average pore diameter and the intermediate porous layer has a lower permeability and lower pore diameter than the porous support layer. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.

Exploring the chemical kinetics of partially oxidized intermediates by combining experiments, theory, and kinetic modeling.

PubMed

Hoyermann, Karlheinz; Mauß, Fabian; Olzmann, Matthias; Welz, Oliver; Zeuch, Thomas

2017-07-19

Partially oxidized intermediates play a central role in combustion and atmospheric chemistry. In this perspective, we focus on the chemical kinetics of alkoxy radicals, peroxy radicals, and Criegee intermediates, which are key species in both combustion and atmospheric environments. These reactive intermediates feature a broad spectrum of chemical diversity. Their reactivity is central to our understanding of how volatile organic compounds are degraded in the atmosphere and converted into secondary organic aerosol. Moreover, they sensitively determine ignition timing in internal combustion engines. The intention of this perspective article is to provide the reader with information about the general mechanisms of reactions initiated by addition of atomic and molecular oxygen to alkyl radicals and ozone to alkenes. We will focus on critical branching points in the subsequent reaction mechanisms and discuss them from a consistent point of view. As a first example of our integrated approach, we will show how experiment, theory, and kinetic modeling have been successfully combined in the first infrared detection of Criegee intermediates during the gas phase ozonolysis. As a second example, we will examine the ignition timing of n-heptane/air mixtures at low and intermediate temperatures. Here, we present a reduced, fuel size independent kinetic model of the complex chemistry initiated by peroxy radicals that has been successfully applied to simulate standard n-heptane combustion experiments.

GroEL actively stimulates folding of the endogenous substrate protein PepQ.

PubMed

Weaver, Jeremy; Jiang, Mengqiu; Roth, Andrew; Puchalla, Jason; Zhang, Junjie; Rye, Hays S

2017-06-30

Many essential proteins cannot fold without help from chaperonins, like the GroELS system of Escherichia coli. How chaperonins accelerate protein folding remains controversial. Here we test key predictions of both passive and active models of GroELS-stimulated folding, using the endogenous E. coli metalloprotease PepQ. While GroELS increases the folding rate of PepQ by over 15-fold, we demonstrate that slow spontaneous folding of PepQ is not caused by aggregation. Fluorescence measurements suggest that, when folding inside the GroEL-GroES cavity, PepQ populates conformations not observed during spontaneous folding in free solution. Using cryo-electron microscopy, we show that the GroEL C-termini make physical contact with the PepQ folding intermediate and help retain it deep within the GroEL cavity, resulting in reduced compactness of the PepQ monomer. Our findings strongly support an active model of chaperonin-mediated protein folding, where partial unfolding of misfolded intermediates plays a key role.

Improving the representation of soluble iron in climate models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahowald, Natalie

Funding from this grant supported Rachel Sanza, Yan Zhang and partially Samuel Albani. Substantial progress has been made on inclusion of mineralogy, showing the quality of the simulations, and the impact on radiation in the CAM4 and CAM5 (Scanza et al., 2015). In addition, the elemental distribution has been evaluated (and partially supported by this grant) (Zhang et al., 2015), showing that using spatial distributions of mineralogy, improved resperentation of Fe, Ca and Al are possible, compared to the limited available data. A new intermediate complexity soluble iron scheme was implemented in the Bulk Aerosol Model (BAM), which was completedmore » as part of Rachel Scanza’s PhD thesis. Currently Rachel is writing up at least two first author papers describing the general methods and comparison to observations (Scanza et al., in prep.), as well as papers describing the sensitivity to preindustrial conditions and interannual variability. This work lead to the lead PI being asked to write a commentary in Nature (Mahowald, 2013) and two review papers (Mahowald et al., 2014, Mahowald et al., submitted) and contributed to related papers (Albani et al., 2016, Albani et al., 2014, Albani et al., 2015).« less

Molecular cytogenetic characterization and stem rust resistance of five wheat-thinopyrum ponticum partial amphiploids

USDA-ARS?s Scientific Manuscript database

Partial amphiploids created by crossing common wheat (Triticum aestivum L.) and Thinopyrum ponticum (Podp.), Barkworth & D. R. Dewey may be resistant to major wheat diseases and are an important intermediate material in wheat breeding. In this study, we examined chromosome composition of five Xiaoy...

Kinetically trapped metastable intermediate of a disulfide-deficient mutant of the starch-binding domain of glucoamylase.

PubMed

Sugimoto, Hayuki; Nakaura, Miho; Nishimura, Shigenori; Karita, Shuichi; Miyake, Hideo; Tanaka, Akiyoshi

2009-08-01

Refolding of a thermally unfolded disulfide-deficient mutant of the starch-binding domain of glucoamylase was investigated using differential scanning calorimetry, isothermal titration calorimetry, CD, and (1)H NMR. When the protein solution was rapidly cooled from a higher temperature, a kinetic intermediate was formed during refolding. The intermediate was unexpectedly stable compared with typical folding intermediates that have short half-lives. It was shown that this intermediate contained substantial secondary structure and tertiary packing and had the same binding ability with beta-cyclodextrin as the native state, suggesting that the intermediate is highly-ordered and native-like on the whole. These characteristics differ from those of partially folded intermediates such as molten globule states. Far-UV CD spectra showed that the secondary structure was once disrupted during the transition from the intermediate to the native state. These results suggest that the intermediate could be an off-pathway type, possibly a misfolded state, that has to undergo unfolding on its way to the native state.

Hoxd11 specifies a program of metanephric kidney development within the intermediate mesoderm of the mouse embryo.

PubMed

Mugford, Joshua W; Sipilä, Petra; Kobayashi, Akio; Behringer, Richard R; McMahon, Andrew P

2008-07-15

The mammalian kidney consists of an array of tubules connected to a ductal system that collectively function to control water/salt balance and to remove waste from the organisms' circulatory system. During mammalian embryogenesis, three kidney structures form within the intermediate mesoderm. The two most anterior structures, the pronephros and the mesonephros, are transitory and largely non-functional, while the most posterior, the metanephros, persists as the adult kidney. We have explored the mechanisms underlying regional specific differentiation of the kidney forming mesoderm. Previous studies have shown a requirement for Hox11 paralogs (Hoxa11, Hoxc11 and Hoxd11) in metanephric development. Mice lacking all Hox11 activity fail to form metanephric kidney structures. We demonstrate that the Hox11 paralog expression is restricted in the intermediate mesoderm to the posterior, metanephric level. When Hoxd11 is ectopically activated in the anterior mesonephros, we observe a partial transformation to a metanephric program of development. Anterior Hoxd11(+) cells activate Six2, a transcription factor required for the maintenance of metanephric tubule progenitors. Additionally, Hoxd11(+) mesonephric tubules exhibit an altered morphology and activate several metanephric specific markers normally confined to distal portions of the functional nephron. Collectively, our data support a model where Hox11 paralogs specify a metanephric developmental program in responsive intermediate mesoderm. This program maintains tubule forming progenitors and instructs a metanephric specific pattern of nephron differentiation.

Protein vivisection reveals elusive intermediates in folding

PubMed Central

Zheng, Zhongzhou; Sosnick, Tobin R.

2010-01-01

Although most folding intermediates escape detection, their characterization is crucial to the elucidation of folding mechanisms. Here we outline a powerful strategy to populate partially unfolded intermediates: A buried aliphatic residue is substituted with a charged residue (e.g., Leu→Glu−) to destabilize and unfold a specific region of the protein. We apply this strategy to Ubiquitin, reversibly trapping a folding intermediate in which the β5 strand is unfolded. The intermediate refolds to a native-like structure upon charge neutralization under mildly acidic conditions. Characterization of the trapped intermediate using NMR and hydrogen exchange methods identifies a second folding intermediate and reveals the order and free energies of the two major folding events on the native side of the rate-limiting step. This general strategy may be combined with other methods and have broad applications in the study of protein folding and other reactions that require trapping of high energy states. PMID:20144618

Prediction of properties and elemental composition of biomass pyrolysis oils by NMR and partial least squares analysis

USDA-ARS?s Scientific Manuscript database

Several partial least squares (PLS) models were created correlating various properties and chemical composition measurements with the 1H and 13C NMR spectra of 73 different of pyrolysis bio-oil samples from various biomass sources (crude and intermediate products), finished oils and small molecule s...

Detonation nanodiamond introduced into samarium doped ceria electrolyte improving performance of solid oxide fuel cell

NASA Astrophysics Data System (ADS)

Pei, Kai; Li, Hongdong; Zou, Guangtian; Yu, Richeng; Zhao, Haofei; Shen, Xi; Wang, Liying; Song, Yanpeng; Qiu, Dongchao

2017-02-01

A novel electrolyte materials of introducing detonation nanodiamond (DNDs) into samarium doped ceria (SDC) is reported here. 1%wt. DNDs doping SDC (named SDC/ND) can enlarge the electrotyle grain size and change the valence of partial ceria. DNDs provide the widen channel to accelerate the mobility of oxygen ions in electrolyte. Larger grain size means that oxygen ions move easier in electrolyte, it can also reduce the alternating current (AC) impedance spectra of internal grains. The lower valence of partial Ce provides more oxygen vacancies to enhance mobility rate of oxygen ions. Hence all of them enhance the transportation of oxygen ions in SDC/ND electrolyte and the OCV. Ultimately the power density of SOFC can reach 762 mw cm-2 at 800 °C (twice higher than pure SDC, which is 319 mw cm-2 at 800 °C), and it remains high power density in the intermediate temperature (600-800 °C). It is relatively high for the electrolyte supported (300 μm) cells.

Mechanism of insulin fibrillation: the structure of insulin under amyloidogenic conditions resembles a protein-folding intermediate.

PubMed

Hua, Qing-xin; Weiss, Michael A

2004-05-14

Insulin undergoes aggregation-coupled misfolding to form a cross-beta assembly. Such fibrillation has long complicated its manufacture and use in the therapy of diabetes mellitus. Of interest as a model for disease-associated amyloids, insulin fibrillation is proposed to occur via partial unfolding of a monomeric intermediate. Here, we describe the solution structure of human insulin under amyloidogenic conditions (pH 2.4 and 60 degrees C). Use of an enhanced sensitivity cryogenic probe at high magnetic field avoids onset of fibrillation during spectral acquisition. A novel partial fold is observed in which the N-terminal segments of the A- and B-chains detach from the core. Unfolding of the N-terminal alpha-helix of the A-chain exposes a hydrophobic surface formed by native-like packing of the remaining alpha-helices. The C-terminal segment of the B-chain, although not well ordered, remains tethered to this partial helical core. We propose that detachment of N-terminal segments makes possible aberrant protein-protein interactions in an amyloidogenic nucleus. Non-cooperative unfolding of the N-terminal A-chain alpha-helix resembles that observed in models of proinsulin folding intermediates and foreshadows the extensive alpha --> beta transition characteristic of mature fibrils.

An index-based algorithm for fast on-line query processing of latent semantic analysis

PubMed Central

Li, Pohan; Wang, Wei

2017-01-01

Latent Semantic Analysis (LSA) is widely used for finding the documents whose semantic is similar to the query of keywords. Although LSA yield promising similar results, the existing LSA algorithms involve lots of unnecessary operations in similarity computation and candidate check during on-line query processing, which is expensive in terms of time cost and cannot efficiently response the query request especially when the dataset becomes large. In this paper, we study the efficiency problem of on-line query processing for LSA towards efficiently searching the similar documents to a given query. We rewrite the similarity equation of LSA combined with an intermediate value called partial similarity that is stored in a designed index called partial index. For reducing the searching space, we give an approximate form of similarity equation, and then develop an efficient algorithm for building partial index, which skips the partial similarities lower than a given threshold θ. Based on partial index, we develop an efficient algorithm called ILSA for supporting fast on-line query processing. The given query is transformed into a pseudo document vector, and the similarities between query and candidate documents are computed by accumulating the partial similarities obtained from the index nodes corresponds to non-zero entries in the pseudo document vector. Compared to the LSA algorithm, ILSA reduces the time cost of on-line query processing by pruning the candidate documents that are not promising and skipping the operations that make little contribution to similarity scores. Extensive experiments through comparison with LSA have been done, which demonstrate the efficiency and effectiveness of our proposed algorithm. PMID:28520747

An index-based algorithm for fast on-line query processing of latent semantic analysis.

PubMed

Zhang, Mingxi; Li, Pohan; Wang, Wei

2017-01-01

Latent Semantic Analysis (LSA) is widely used for finding the documents whose semantic is similar to the query of keywords. Although LSA yield promising similar results, the existing LSA algorithms involve lots of unnecessary operations in similarity computation and candidate check during on-line query processing, which is expensive in terms of time cost and cannot efficiently response the query request especially when the dataset becomes large. In this paper, we study the efficiency problem of on-line query processing for LSA towards efficiently searching the similar documents to a given query. We rewrite the similarity equation of LSA combined with an intermediate value called partial similarity that is stored in a designed index called partial index. For reducing the searching space, we give an approximate form of similarity equation, and then develop an efficient algorithm for building partial index, which skips the partial similarities lower than a given threshold θ. Based on partial index, we develop an efficient algorithm called ILSA for supporting fast on-line query processing. The given query is transformed into a pseudo document vector, and the similarities between query and candidate documents are computed by accumulating the partial similarities obtained from the index nodes corresponds to non-zero entries in the pseudo document vector. Compared to the LSA algorithm, ILSA reduces the time cost of on-line query processing by pruning the candidate documents that are not promising and skipping the operations that make little contribution to similarity scores. Extensive experiments through comparison with LSA have been done, which demonstrate the efficiency and effectiveness of our proposed algorithm.

Catalyst containing oxygen transport membrane

DOEpatents

Lane, Jonathan A.; Wilson, Jamie R.; Christie, Gervase Maxwell; Petigny, Nathalie; Sarantopoulos, Christos

2017-02-07

A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a microstructure exhibiting substantially uniform pore size distribution as a result of using PMMA pore forming materials or a bi-modal particle size distribution of the porous support layer materials. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.

Hexafluoroisopropanol-induced helix-sheet transition of stem bromelain: correlation to function.

PubMed

Dave, Sandeep; Dkhar, H Kitdorlang; Singh, Manvendra Pratap; Gupta, Garima; Chandra, Vemika; Mahajan, Sahil; Gupta, Pawan

2010-06-01

Stem bromelain is a proteolytic phytoprotein with a variety of therapeutic effects. Understanding its structural properties could provide insight into the mechanisms underlying its clinical utility. Stem bromelain was evaluated for its conformational and folding properties at the pH conditions it encounters when administered orally. It exists as a partially folded intermediate at pH 2.0. The conformational changes to this intermediate state were evaluated using fluorinated alcohols known to induce changes similar to those seen in vivo. Studies using circular dichroism, fluorescence emission spectroscopy, binding of the hydrophobic dye 1-anilino-8-naphthalene sulfonic acid and mass spectrometry indicate that treatment with 10-30% hexafluoroisopropanol induces the partially folded intermediate to adopt much of the native protein's secondary structure, but only a rudimentary tertiary structure, characteristic of the molten globule state. Addition of slightly higher concentrations of hexafluoroisopropanol caused transformation from an alpha-helix to a beta-sheet and induced formation of a compact nonnative structure. This nonnative form was more inhibitory of cell survival than either the native or the partially folded intermediate forms, as measured by enhanced suppression of proliferative cues (e.g., extracellular-signal-regulated kinase) and initiation of apoptotic events. The nonnative form also showed better antitumorigenic properties, as evaluated using an induced two-stage mouse skin papilloma model. In contrast, the nonnative state showed only a fraction of the proteolytic activity of the native form. This study demonstrates that hexafluoroisopropanol can induce a conformational change in stem bromelain to a form with potentially useful therapeutic properties different from those of the native protein. Copyright 2010 Elsevier Ltd. All rights reserved.

PA03.13. Effect of triphaladi rasayana along with yoga therapy on low grade non hodgkins lymphoma and resistant intermediate and high grade non hodgkins lymphoma

PubMed Central

Soumya, MS Surya; Sarasa, TP

2013-01-01

Purpose: 1. To find out the effect of Thriphaladi Rasayana along with Yoga Therapy on low grade Non Hodgkins Lymphoma and resistant intermediate and high grade NonHodgkins Lymphoma. 2. To apply a less costly, less morbid, well accepted method of treatment on NHL. 3.To find a simple method to increase the immunity. 4.To try a drug which is easy to prepare? Method: Purposive sampling technique was used for the study. Sample of 30 patients age range 25 75 years with histologicaly proven NonHodgkins lymphoma, attending the M.O.I.O.P of the regional cancer centre during a period of 18 months. Groups1) Low grade NonHodgkins Lymphoma 2) Resistant intermediate &High grade NonHodgkins lymphoma (failed chemotherapy) were taken. Procedure : 2 groups were given Triphaladhi Rasayana (15 grams of powder with ghee and honey) twice dailymorning& at bed time with milk as anupana for period of 1month along with selected yoga asanas and niyama? Result: Symptoms included were fever, night sweats, weight loss, lymph nodes enlargement, splenomegaly, and hepatomegaly. In low grade symptom relief was noted in almost all cases. Lymph node changes notedLow grade5 2% (complete remission), 38% (partial remission), 10% (no change), intermediate35% (CR), 52% (PR) & 13% (NC), High grade67% (CR), 33%(PR). Hepatomegaly changes :ve in low grade92.86%, intermediate 90.9% & high grade100%. Splenomegaly changes :ve in low grade92.86%, intermediate72.72% & high grade80% Over all remission status of 30 patientscomplete remission30%, partial remission 30% & no change30%? Conclusion: Thriphaladirasayana along with Yoga therapy is very effective in Low grade NonHodgkins lymphoma and resistant intermediate and high grade Non hodgkins Lymphoma?

Partially entangled states bridge in quantum teleportation

NASA Astrophysics Data System (ADS)

Cai, Xiao-Fei; Yu, Xu-Tao; Shi, Li-Hui; Zhang, Zai-Chen

2014-10-01

The traditional method for information transfer in a quantum communication system using partially entangled state resource is quantum distillation or direct teleportation. In order to reduce the waiting time cost in hop-by-hop transmission and execute independently in each node, we propose a quantum bridging method with partially entangled states to teleport quantum states from source node to destination node. We also prove that the designed specific quantum bridging circuit is feasible for partially entangled states teleportation across multiple intermediate nodes. Compared to two traditional ways, our partially entanglement quantum bridging method uses simpler logic gates, has better security, and can be used in less quantum resource situation.

Do Partial Home Smoking Bans Signal Progress toward a Smoke-Free Home?

ERIC Educational Resources Information Center

Kegler, Michelle C.; Haardörfer, Regine; Bundy, Lucja T.; Escoffery, Cam; Berg, Carla J.; Fernandez, Maria; Williams, Rebecca; Hovell, Mel

2016-01-01

Understanding who establishes partial home smoking bans, what these bans cover, and whether they are an intermediate step in going smoke-free would help to inform smoke-free home interventions. Participants were recruited from United Way of Greater Atlanta's 2-1-1 contact center. Data were collected at baseline, 3 and 6 months via telephone…

Structural analysis of kinetic folding intermediates for a TIM barrel protein, indole-3-glycerol phosphate synthase, by hydrogen exchange mass spectrometry and Gō-model simulation

PubMed Central

Gu, Zhenyu; Rao, Maithreyi K.; Forsyth, William R.

2009-01-01

The structures of partially-folded states appearing during the folding of a (βα)8 TIM barrel protein, the indole-3-glycerol phosphate synthase from S. solfataricus (sIGPS), was assessed by hydrogen exchange mass spectrometry (HX-MS) and Gō-model simulations. HX-MS analysis of the peptic peptides derived from the pulse-labeled product of the sub-millisecond folding reaction from the urea-denatured state revealed strong protection in the (βα)4 region, modest protection in the neighboring (βα)1–3 and (βα)5β6 segments and no significant protection in the remaining N- and C-terminal segments. These results demonstrate that this species is not a collapsed form of the unfolded state under native-favoring conditions nor is it the native state formed via fast-track folding. However, the striking contrast of these results with the strong protection observed in the (βα)2–5β6 region after 5 s of folding demonstrates that these species represent kinetically-distinct folding intermediates that are not identical as previously thought. A re-examination of the kinetic folding mechanism by chevron analysis of fluorescence data confirmed distinct roles for these two species: the burst-phase intermediate is predicted to be a misfolded, off-pathway intermediate while the subsequent 5 s intermediate corresponds to an on-pathway equilibrium intermediate. Comparison with the predictions using a Cα Gō-model simulation of the kinetic folding reaction for sIGPS shows good agreement with the core of structure offering protection against exchange in the on-pathway intermediate(s). Because the native-centric Gō-model simulations do not explicitly include sequence-specific information, the simulation results support the hypothesis that the topology of TIM barrel proteins is a primary determinant of the folding free energy surface for the productive folding reaction. The early misfolding reaction must involve aspects of non-native structure not detected by the Gō-model simulation. PMID:17942114

Synchronization versus decoherence of neutrino oscillations at intermediate densities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raffelt, Georg G.; Tamborra, Irene

2010-12-15

We study collective oscillations of a two-flavor neutrino system with arbitrary but fixed density. In the vacuum limit, modes with different energies quickly dephase (kinematical decoherence), whereas in the limit of infinite density they lock to each other (synchronization). For intermediate densities, we find different classes of solutions. There is always a phase transition in the sense of partial synchronization occurring only above a density threshold. For small mixing angles, partial or complete decoherence can be induced by a parametric resonance, introducing a new time scale to the problem, the final outcome depending on the spectrum and mixing angle. Wemore » derive an analytic relation that allows us to calculate the late-time degree of coherence based on the spectrum alone.« less

Fluorinated elastomeric materials

DOEpatents

Lagow, Richard J.; Dumitru, Earl T.

1986-11-04

This invention relates to a method of making perfluorinated elastomeric materials, and to materials made by such methods. In the full synthetic scheme, a partially fluorinated polymeric compound, with moieties to prevent crystallization, is created. It is then crosslinked to a desired degree, then perfluorinated. Various intermediate materials, such as partially fluorinated crosslinked polymers, have useful properties, and are or may become commercially available. One embodiment of this invention therefore relates to perfluorination of a selected partially fluorinated, crosslinked material, which is one step of the full synthetic scheme.

Fluorinated elastomeric materials

DOEpatents

Lagow, Richard J.; Dumitru, Earl T.

1990-02-13

This invention relates to a method of making perfluorinated elastomeric materials, and to materials made by such methods. In the full synthetic scheme, a partially fluorinated polymeric compound, with moieties to prevent crystallization, is created. It is then crosslinked to a desired degree, then perfluorinated. Various intermediate materials, such as partially fluorinated crosslinked polymers, have useful properties, and are or may become commercially available. One embodiment of this invention therefore relates to perfluorination of a selected partially fluorinated, crosslinked material, which is one step of the full synthetic scheme.

Variation in chromosome constitution of the Xiaoyan series partial amphiploids and its relations to stripe rust and stem rust resistance

USDA-ARS?s Scientific Manuscript database

In the tertiary gene pool of wheat, tall wheatgrass Thinopyrum ponticum (2n = 10x = 70) is an excellent source of resistance genes against numerous wheat diseases. The creation of wheat-Th. ponticum partial amphiploids is an intermediate step for transferring the useful genes from Th. ponticum to w...

Dehydration of 1-octadecanol over H-BEA: A combined experimental and computational study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Wenji; Liu, Yuanshuai; Barath, Eszter

Liquid phase dehydration of 1-octdecanol, which is intermediately formed during the hydrodeoxygenation of microalgae oil, has been explored in a combined experimental and computational study. The alkyl chain of C18 alcohol interacts with acid sites during diffusion inside the zeolite pores, resulting in an inefficient utilization of the Brønsted acid sites for samples with high acid site concentrations. The parallel intra- and inter- molecular dehydration pathways having different activation energies pass through alternative reaction intermediates. Formation of surface-bound alkoxide species is the rate-limiting step during intramolecular dehydration, whereas intermolecular dehydration proceeds via a bulky dimer intermediate. Octadecene is the primarymore » dehydration product over H-BEA at 533 K. Despite of the main contribution of Brønsted acid sites towards both dehydration pathways, Lewis acid sites are also active in the formation of dioctadecyl ether. The intramolecular dehydration to octadecene and cleavage of the intermediately formed ether, however, require strong BAS. L. Wang, D. Mei and J. A. Lercher, acknowledge the partial support from the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle. Computing time was granted by the grand challenge of computational catalysis of the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL) and by the National Energy Research Scientific Computing Center (NERSC). EMSL is a national scientific user facility located at Pacific Northwest National Laboratory (PNNL) and sponsored by DOE’s Office of Biological and Environmental Research.« less

The Complex History of Alarcon Rise Mid-Ocean Ridge Rhyolite Revealed through Mineral Chemistry

NASA Astrophysics Data System (ADS)

Dreyer, B. M.; Portner, R. A.; Clague, D. A.; Daczko, N. R.; Castillo, P.; Bindeman, I. N.

2014-12-01

A suite of basalts to rhyolites recovered from the Alarcon Rise, the northern extension of the intermediate spreading-rate East Pacific Rise, provides an unparalleled test of established mechanisms for high-Si lava formation at ridges. Rhyolites are ≤35% phyric and poorly vesicular. Mafic xenoclasts are common, and plagioclase is the dominant phase. Olivine and clinopyroxene are also common, and orthopyroxene, FeTi-oxides, zircon, and rare pyrite blebs are present. Major and trace element glass data are consistent with MELTS models of fractional crystallization from a parental melt, but a diverse mineral population records added complexity. Olivine and plagioclase compositions are broadly consistent with models, with the exception of more variable Fo52-77 and An87-28 in a basaltic andesitic composition where pigeonite is predicted to replace olivine in the crystallizing assemblage between ~1085-1015°C; pigeonites analyzed in an andesite have lower Ca and Fe than predicted. Clinopyroxene variability generally increases with host melt SiO2, from Mg# 86-84 in basalts to Mg# 80-21 in rhyolites, and zoning is common with higher-MgO anhedral cores mantled by lower-MgO euhedral rims. Cooler magmas aided the preservation of disequilibrium and are supported by ~715-835°C Ti-in-zircon and ilmenite-magnetite thermometry in rhyolites. Despite a well-predicted liquid line of decent, multiple signals of chemical disequilibrium in intermediate to silicic melts support mixing of magmatic batches and/or assimilation of partially hydrous crust. Assimilation is permissible given δ18O values that are lower than expected solely from fractional crystallization (i.e., <6.3‰ at 77% SiO2), but assimilation extent is limited on the basis of δD ~82±8 and Pacific MORB-like 87Sr/86Sr. Zircon Hf-isotopes and trace element patterns support a juvenile oceanic crustal source. Whereas depleted Pacific MORB mantle source reservoir is supported by whole rock Sr-Nd isotopes, slight enrichments in zircon 176Hf/177Hf and whole rock 207,206Pb/204Pb may indicate an enriched MORB mantle component. In conclusion, mid-ocean rhyolite at Alarcon formed from a variety of petrogenetic processes including magma-mixing, assimilation, and crystallization following partial melting of slightly heterogeneous mantle source(s).

Molecular and morphological characterization of the cercariae of Lecithodendrium linstowi (Dollfus, 1931), a trematode of bats, and incrimination of the first intermediate snail host, Radix balthica.

PubMed

Enabulele, Egie E; Lawton, Scott P; Walker, Anthony J; Kirk, Ruth S

2018-03-01

Lecithodendrium linstowi is one of the most prevalent and abundant trematodes of bats, but the larval stages and intermediate hosts have not been identified. We present the first molecular and morphological characterization of the cercariae of L. linstowi based on a phylogenetic analysis of partial fragments of LSU and ITS2 rDNA. The first intermediate host was incriminated as Radix balthica by DNA barcoding using cox1 and ITS2 sequences, although the snail morphologically resembled Radix peregra, emphasizing the requirement for molecular identification of lymnaeids as important intermediate hosts of medical and veterinary impact. The application of molecular data in this study has enabled linkage of life cycle stages and accurate incrimination of the first intermediate host.

Selective Hydrodeoxygenation of Vegetable Oils and Waste Cooking Oils to Green Diesel Using a Silica-Supported Ir-ReOx Bimetallic Catalyst.

PubMed

Liu, Sibao; Simonetti, Trent; Zheng, Weiqing; Saha, Basudeb

2018-05-09

High yields of diesel-range alkanes are prepared by hydrodeoxygenation of vegetable oils and waste cooking oils over ReO x -modified Ir/SiO 2 catalysts under mild reaction conditions. The catalyst containing a Re/Ir molar ratio of 3 exhibits the best performance, achieving 79-85 wt % yield of diesel-range alkanes at 453 K and 2 MPa H 2 . The yield is nearly quantitative for the theoretical possible long-chain alkanes on the basis of weight of the converted oils. The catalyst retains comparable activity upon regeneration through calcination. Control experiments using probe molecules as model substrates suggest that C=C bonds of unsaturated triglycerides and free fatty acids are first hydrogenated to their corresponding saturated intermediates, which are then converted to aldehyde intermediates through hydrogenolysis of acyl C-O bonds and subsequently hydrogenated to fatty alcohols. Finally, long-chain alkanes without any carbon loss are formed by direct hydrogenolysis of the fatty alcohols. Small amounts of alkanes with one carbon fewer are also formed by decarbonylation of the aldehyde intermediates. A synergy between Ir and partially reduced ReO x sites is discussed to elucidate the high activity of Ir-ReO x /SiO 2. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phase behavior and reactive transport of partial melt in heterogeneous mantle model

NASA Astrophysics Data System (ADS)

Jordan, J.; Hesse, M. A.

2013-12-01

The reactive transport of partial melt is the key process that leads to the chemical and physical differentiation of terrestrial planets and smaller celestial bodies. The essential role of the lithological heterogeneities during partial melting of the mantle is increasingly recognized. How far can enriched melts propagate while interacting with the ambient mantle? Can the melt flow emanating from a fertile heterogeneity be localized through a reactive infiltration feedback in a model without exogenous factors or contrived initial conditions? A full understanding of the role of heterogeneities requires reactive melt transport models that account for the phase behavior of major elements. Previous work on reactive transport in the mantle focuses on trace element partitioning; we present the first nonlinear chromatographic analysis of reactive melt transport in systems with binary solid solution. Our analysis shows that reactive melt transport in systems with binary solid solution leads to the formation of two separate reaction fronts: a slow melting/freezing front along which enthalpy change is dominant and a fast dissolution/precipitation front along which compositional changes are dominated by an ion-exchange process over enthalpy change. An intermediate state forms between these two fronts with a bulk-rock composition and enthalpy that are not necessarily bounded by the bulk-rock composition and enthalpy of either the enriched heterogeneity or the depleted ambient mantle. The formation of this intermediate state makes it difficult to anticipate the porosity changes and hence the stability of reaction fronts. Therefore, we develop a graphical representation for the solution that allows identification of the intermediate state by inspection, for all possible bulk-rock compositions and enthalpies of the heterogeneity and the ambient mantle. We apply the analysis to the partial melting of an enriched heterogeneity. This leads to the formation of moving precipitation front that followes a stationary melting front which creates low porosity intermediate states. Therefore, localization of the melt flow is not observed because the precipitation front is stable and the melting front is always stationary under these conditions. This analysis illustrates the counterintuitive behavior that can arise when the phase behavior is taken into account and is a first step to understanding reactive melt transport and the reactive constraints on channelization in partial melts. ¬¬

A partially folded structure of amyloid-beta(1-40) in an aqueous environment.

PubMed

Vivekanandan, Subramanian; Brender, Jeffrey R; Lee, Shirley Y; Ramamoorthy, Ayyalusamy

2011-07-29

Aggregation of the Aβ(1-40) peptide is linked to the development of extracellular plaques characteristic of Alzheimer's disease. While previous studies commonly show the Aβ(1-40) is largely unstructured in solution, we show that Aβ(1-40) can adopt a compact, partially folded structure. In this structure (PDB ID: 2LFM), the central hydrophobic region of the peptide forms a 3(10) helix from H13 to D23 and the N- and C-termini collapse against the helix due to the clustering of hydrophobic residues. Helical intermediates have been predicted to be crucial on-pathway intermediates in amyloid fibrillogenesis, and the structure presented here presents a new target for investigation of early events in Aβ(1-40) fibrillogenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

Development and Validation of a Novel Robotic Procedure Specific Simulation Platform: Partial Nephrectomy.

PubMed

Hung, Andrew J; Shah, Swar H; Dalag, Leonard; Shin, Daniel; Gill, Inderbir S

2015-08-01

We developed a novel procedure specific simulation platform for robotic partial nephrectomy. In this study we prospectively evaluate its face, content, construct and concurrent validity. This hybrid platform features augmented reality and virtual reality. Augmented reality involves 3-dimensional robotic partial nephrectomy surgical videos overlaid with virtual instruments to teach surgical anatomy, technical skills and operative steps. Advanced technical skills are assessed with an embedded full virtual reality renorrhaphy task. Participants were classified as novice (no surgical training, 15), intermediate (less than 100 robotic cases, 13) or expert (100 or more robotic cases, 14) and prospectively assessed. Cohort performance was compared with the Kruskal-Wallis test (construct validity). Post-study questionnaire was used to assess the realism of simulation (face validity) and usefulness for training (content validity). Concurrent validity evaluated correlation between virtual reality renorrhaphy task and a live porcine robotic partial nephrectomy performance (Spearman's analysis). Experts rated the augmented reality content as realistic (median 8/10) and helpful for resident/fellow training (8.0-8.2/10). Experts rated the platform highly for teaching anatomy (9/10) and operative steps (8.5/10) but moderately for technical skills (7.5/10). Experts and intermediates outperformed novices (construct validity) in efficiency (p=0.0002) and accuracy (p=0.002). For virtual reality renorrhaphy, experts outperformed intermediates on GEARS metrics (p=0.002). Virtual reality renorrhaphy and in vivo porcine robotic partial nephrectomy performance correlated significantly (r=0.8, p <0.0001) (concurrent validity). This augmented reality simulation platform displayed face, content and construct validity. Performance in the procedure specific virtual reality task correlated highly with a porcine model (concurrent validity). Future efforts will integrate procedure specific virtual reality tasks and their global assessment. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Defining the Nature of Thermal Intermediate in 3 State Folding Proteins: Apoflavodoxin, a Study Case

PubMed Central

García-Fandiño, Rebeca; Bernadó, Pau; Ayuso-Tejedor, Sara; Sancho, Javier; Orozco, Modesto

2012-01-01

The early stages of the thermal unfolding of apoflavodoxin have been determined by using atomistic multi microsecond-scale molecular dynamics (MD) simulations complemented with a variety of experimental techniques. Results strongly suggest that the intermediate is reached very early in the thermal unfolding process and that it has the properties of an “activated” form of the native state, where thermal fluctuations in the loops break loop-loop contacts. The unrestrained loops gain then kinetic energy corrupting short secondary structure elements without corrupting the core of the protein. The MD-derived ensembles agree with experimental observables and draw a picture of the intermediate state inconsistent with a well-defined structure and characteristic of a typical partially disordered protein. Our results allow us to speculate that proteins with a well packed core connected by long loops might behave as partially disordered proteins under native conditions, or alternatively behave as three state folders. Small details in the sequence, easily tunable by evolution, can yield to one or the other type of proteins. PMID:22927805

Mechanistic Insights into the Catalytic Oxidation of Carboxylic Acids on Au/TiO 2: Partial Oxidation of Propionic and Butyric Acid to Gold Ketenylidene through Unsaturated Acids

DOE Office of Scientific and Technical Information (OSTI.GOV)

McEntee, Monica; Tang, Wenjie; Neurock, Matthew

Here, the partial oxidation of model C 2–C 4 (acetic, propionic, and butyric) carboxylic acids on Au/TiO 2 catalysts consisting of Au particles ~3 nm in size was investigated using transmission infrared spectroscopy and density functional theory. All three acids readily undergo oxidative dehydrogenation on Au/TiO 2. Propionic and butyric acid dehydrogenate at the C2–C3 positions, whereas acetic acid dehydrogenates at the C1–C2 position. The resulting acrylate and crotonate intermediates are subsequently oxidized to form β-keto acids that decarboxylate. All three acids form a gold ketenylidene intermediate, Au 2C=C=O, along the way to their full oxidation to form CO 2.more » Infrared measurements of Au 2C=C=O formation as a function of time provides a surface spectroscopic probe of the kinetics for the activation and oxidative dehydrogenation of the alkyl groups in the carboxylate intermediates that form.« less

Mechanistic Insights into the Catalytic Oxidation of Carboxylic Acids on Au/TiO 2: Partial Oxidation of Propionic and Butyric Acid to Gold Ketenylidene through Unsaturated Acids

DOE PAGES

McEntee, Monica; Tang, Wenjie; Neurock, Matthew; ...

2014-12-12

Here, the partial oxidation of model C 2–C 4 (acetic, propionic, and butyric) carboxylic acids on Au/TiO 2 catalysts consisting of Au particles ~3 nm in size was investigated using transmission infrared spectroscopy and density functional theory. All three acids readily undergo oxidative dehydrogenation on Au/TiO 2. Propionic and butyric acid dehydrogenate at the C2–C3 positions, whereas acetic acid dehydrogenates at the C1–C2 position. The resulting acrylate and crotonate intermediates are subsequently oxidized to form β-keto acids that decarboxylate. All three acids form a gold ketenylidene intermediate, Au 2C=C=O, along the way to their full oxidation to form CO 2.more » Infrared measurements of Au 2C=C=O formation as a function of time provides a surface spectroscopic probe of the kinetics for the activation and oxidative dehydrogenation of the alkyl groups in the carboxylate intermediates that form.« less

Characterization of a transient +2 sulfur oxidation state intermediate from the oxidation of aqueous sulfide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vairavmurthy, M.A.; Zhou, Weiqing

1995-04-01

The oxidation H{sub 2}S to sulfate involves a net transfer of eight electrons and occurs through the formation of several partially oxidized intermediates with oxidation states ranging from {minus}1 to +5. Known intermediates include elemental sulfur (oxidation state 0), polysulfides (outer sulfur: {minus}1, inner sulfur: 0), sulfite (+4) and thiosulfate (outer sulfur: {minus}1, inner sulfur: +5). A noticeable gap in this series of intermediates is that of a +2 sulfur oxidation state oxoacid/oxoanion species, which was never detected experimentally. Here, we present evidence of the transient existence of +2 oxidation state intermediate in the Ni(II)-catalyzed oxidation of aqueous sulfide. X-raymore » absorption near-edge structure (XANES) spectroscopy and Fourier-transform-infrared (FT-IR) spectroscopy were used to characterize this species; they suggest that it has a sulfoxylate ion (SO{sub 2}{sup 2{minus}}) structure.« less

RPA Stabilization of Single-Stranded DNA Is Critical for Break-Induced Replication.

PubMed

Ruff, Patrick; Donnianni, Roberto A; Glancy, Eleanor; Oh, Julyun; Symington, Lorraine S

2016-12-20

DNA double-strand breaks (DSBs) are cytotoxic lesions that must be accurately repaired to maintain genome stability. Replication protein A (RPA) plays an important role in homology-dependent repair of DSBs by protecting the single-stranded DNA (ssDNA) intermediates formed by end resection and by facilitating Rad51 loading. We found that hypomorphic mutants of RFA1 that support intra-chromosomal homologous recombination are profoundly defective for repair processes involving long tracts of DNA synthesis, in particular break-induced replication (BIR). The BIR defects of the rfa1 mutants could be partially suppressed by eliminating the Sgs1-Dna2 resection pathway, suggesting that Dna2 nuclease attacks the ssDNA formed during end resection when not fully protected by RPA. Overexpression of Rad51 was also found to suppress the rfa1 BIR defects. We suggest that Rad51 binding to the ssDNA formed by excessive end resection and during D-loop migration can partially compensate for dysfunctional RPA. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Mutational and Functional Analysis of the β-Carotene Ketolase Involved in the Production of Canthaxanthin and Astaxanthin

PubMed Central

Ye, Rick W.; Stead, Kristen J.; Yao, Henry; He, Hongxian

2006-01-01

Biosynthesis of the commercial carotenoids canthaxanthin and astaxanthin requires β-carotene ketolase. The functional importance of the conserved amino acid residues of this enzyme from Paracoccus sp. strain N81106 (formerly classified as Agrobacterium aurantiacum) was analyzed by alanine-scanning mutagenesis. Mutations in the three highly conserved histidine motifs involved in iron coordination abolished its ability to catalyze the formation of ketocarotenoids. This supports the hypothesis that the CrtW ketolase belongs to the family of iron-dependent integral membrane proteins. Most of the mutations generated at other highly conserved residues resulted in partial activity. All partially active mutants showed a higher amount of adonixanthin accumulation than did the wild type when expressed in Escherichia coli cells harboring the zeaxanthin biosynthetic gene cluster. Some of the partially active mutants also produced a significant amount of echinenone when expressed in cells producing β-carotene. In fact, expression of a mutant carrying D117A resulted in the accumulation of echinenone as the predominant carotenoid. These observations indicate that partial inactivation of the CrtW ketolase can often lead to the production of monoketolated intermediates. In order to improve the conversion rate of astaxanthin catalyzed by the CrtW ketolase, a color screening system was developed. Three randomly generated mutants, carrying L175M, M99V, and M99I, were identified to have improved activity. These mutants are potentially useful in pathway engineering for the production of astaxanthin. PMID:16957201

Unfolding Kinetics of β-Lactoglobulin Induced by Surfactant and Denaturant: A Stopped-Flow/Fluorescence Study

PubMed Central

Viseu, Maria Isabel; Melo, Eduardo P.; Carvalho, Teresa Isabel; Correia, Raquel F.; Costa, Sílvia M. B.

2007-01-01

The β→α transition of β-lactoglobulin, a globular protein abundant in the milk of several mammals, is investigated in this work. This transition, induced by the cationic surfactant dodecyltrimethylammonium chloride (DTAC), is accompanied by partial unfolding of the protein. In this work, unfolding of bovine β-lactoglobulin in DTAC is compared with its unfolding induced by the chemical denaturant guanidine hydrochloride (GnHCl). The final protein states attained in the two media have quite different secondary structure: in DTAC the α-helical content increases, leading to the so-called α-state; in GnHCl the amount of ordered secondary-structure decreases, resulting in a random coil-rich final state (denatured, or D, state). To obtain information on both mechanistic routes, in DTAC and GnHCl, and to characterize intermediates, the kinetics of unfolding were investigated in the two media. Equilibrium and kinetic data show the partial accumulation of an on-pathway intermediate in each unfolding route: in DTAC, an intermediate (I1) with mostly native secondary structure but loose tertiary structure appears between the native (β) and α-states; in GnHCl, another intermediate (I2) appears between states β and D. Kinetic rate constants follow a linear Chevron-plot representation in GnHCl, but show a more complex mechanism in DTAC, which acts like a stronger binding species. PMID:17693475

A macroinvertebrate assessment of Ozark streams located in lead-zinc mining areas of the Viburnum Trend in southeastern Missouri, USA

USGS Publications Warehouse

Poulton, Barry C.; Allert, Ann L.; Besser, John M.; Schmitt, Christopher J.; Brumbaugh, William G.; Fairchild, James F.

2010-01-01

The Viburnum Trend lead-zinc mining subdistrict is located in the southeast Missouri portion of the Ozark Plateau. In 2003 and 2004, we assessed the ecological effects of mining in several watersheds in the region. We included macroinvertebrate surveys, habitat assessments, and analysis of metals in sediment, pore water, and aquatic biota. Macroinvertebrates were sampled at 21 sites to determine aquatic life impairment status (full, partial, or nonsupport) and relative biotic condition scores. Macroinvertebrate biotic condition scores were significantly correlated with cadmium, nickel, lead, zinc, and specific conductance in 2003 (r = -0.61 to -0.68) and with cadmium, lead, and pore water toxic units in 2004 (r = -0.55 to -0.57). Reference sites were fully supporting of aquatic life and had the lowest metals concentrations and among the highest biotic condition scores in both years. Sites directly downstream from mining and related activities were partially supporting, with biotic condition scores 10% to 58% lower than reference sites. Sites located greater distances downstream from mining activities had intermediate scores and concentrations of metals. Results indicate that elevated concentrations of metals originating from mining activities were the underlying cause of aquatic life impairment in several of the streams studied. There was general concurrence among the adversely affected sites in how the various indicators responded to mining activities during the overall study.

Theoretical study of bismuth-doped cadmium telluride

NASA Astrophysics Data System (ADS)

Menendez-Proupin, E.; Rios-Gonzalez, J. A.; Pena, J. L.

Cadmium telluride heavily doped with bismuth has been proposed as an absorber with an intermediate band for solar cells. Increase in the photocurrent has been shown recently, although the overall cell efficiency has not improved. In this work, we study the electronic structure and the formation energies of the defects associated to bismuth impurities. We have performed electronic structure calculations within generalized density functional theory, using the exchange-correlation functional HSE(w) , where the range-separation parameter w has been tuned to reproduce the CdTe bandgap. Improving upon previous reports, we have included the spin-orbit interaction, which modifies the structure of the valence band and the energy levels of bismuth. We have found that interstitial Bi (Bii) tends to occupy Cd vacancies, cadmium substitution (BiCd) creates single donor level, while tellurium substitution (BiTe) is a shallow single acceptor. We investigate the interaction between these point defects and how can they be combined to create a partially filled intermediate band. Supported by FONDECYT Grant 1130437, CONACYT-SENER SUSTENTABILIDAD ENERGETICA/project CeMIE-Sol PY-207450/25 and PY-207450/26. JARG acknowledges CONACYT fellowship for research visit. Powered@NLHPC (ECM-02).

Four-Photon Stark Induced Ladder Climbing Prepares Large Ensemble of H2in Selected High Lying Vibrational Levels

NASA Astrophysics Data System (ADS)

Mukherjee, Nandini; Perreault, William; Zare, Richard

2017-04-01

To selectively prepare highly vibrationally excited quantum states of molecules like H2, we present a novel multi-photon ladder-climbing technique where the successive rungs of the ladder are connected by Stark-induced adiabatic Raman passage (SARP). Previously, we have demonstrated that SARP achieves complete population transfer from the v = 0 to the v = 1 and v = 4 levels of H2. We show here that SARP can be generalized into a continuously coupled, multiphoton adiabatic passage which uses one or more intermediate states having strong Raman coupling to access highly vibrationally excited states weakly coupled to the ground state. As an example, we consider the case of four-photon coherent excitation to high vibrational levels of H2 via an intermediate level coupled to both the initial and target levels by two-photon SARP. Using a sequence of commercially available single mode, nanosecond lasers, a pump pulse partially overlapping with two Stokes pulses, we show that the complete population of v = 0 can be selectively transferred to the most weakly coupled v = 6 and v = 9 vibrational levels of H2, without leaving any population stranded in the intermediate level. The present method provides a practical way of generating an entangled pair of fragments without resorting to an ultracold system. This work has been supported by US Army Research Office under ARO Grant No. W911NF-16-1-1061.

The Organization of Collective Group Movements in Wild Barbary Macaques (Macaca sylvanus): Social Structure Drives Processes of Group Coordination in Macaques

PubMed Central

Seltmann, Anne; Majolo, Bonaventura

2013-01-01

Social animals have to coordinate activities and collective movements to benefit from the advantages of group living. Animals in large groups maintain cohesion by self-organization processes whereas in smaller groups consensus decisions can be reached. Where consensus decisions are relevant leadership may emerge. Variation in the organization of collective movements has been linked to variation in female social tolerance among macaque species ranging from despotic to egalitarian. Here we investigated the processes underlying group movements in a wild macaque species characterized by a degree of social tolerance intermediate to previously studied congeneric species. We focused on processes before, during and after the departure of the first individual. To this end, we observed one group of wild Barbary macaques (Macaca sylvanus) in the Middle Atlas, Morocco using all-occurrence behaviour sampling of 199 collective movements. We found that initiators of a collective movement usually chose the direction in which more individuals displayed pre-departure behavior. Dominant individuals contributed to group movements more than subordinates, especially juveniles, measured as frequencies of successful initiations and pre-departure behaviour. Joining was determined by affiliative relationships and the number of individuals that already joined the movement (mimetism). Thus, in our study group partially shared consensus decisions mediated by selective mimetism seemed to be prevalent, overall supporting the suggestion that a species’ social style affects the organization of group movements. As only the most tolerant species show equally shared consensus decisions whereas in others the decision is partially shared with a bias to dominant individuals the type of consensus decisions seems to follow a stepwise relation. Joining order may also follow a stepwise, however opposite, relationship, because dominance only determined joining in highly despotic, but not in intermediate and tolerant species. PMID:23805305

Effect of plasma nitriding on the structural stability and hydrogen absorption capability of Pd-coated Nb during thermal treatment

NASA Astrophysics Data System (ADS)

Ohtsu, Naofumi; Kozuka, Taro; Shibata, Yuga; Yamane, Misao

2017-11-01

Plasma nitriding was explored for improving the thermal stability of a composite hydrogen permeable membrane comprising a Pd coating on Nb substrate. A NbN intermediate layer was formed on the Nb substrate, and the progress of interdiffusion and deterioration of hydrogen absorption behavior after a thermal treatment at 573 and 773 K, respectively, were investigated. The intermediate layer significantly suppressed the interdiffusion between the coating and the substrate. Furthermore, an increase in the NbN concentration of the intermediate layer enhanced the suppression efficiency. However, the hydrogen permeability of the intermediate layer was significantly low, and hence, an increase in NbN concentration further decreased the hydrogen permeability. We concluded that the nitride layer with a high NbN content was unsuitable as an intermediate layer owing to its low hydrogen permeability, while the partial nitride layer with a low NbN content was inefficient in suppressing the interdiffusion.

Canada Warbler use of harvested stands following timber management in the southern portion of their range

USGS Publications Warehouse

Becker, Douglas A.; Wood, Petra B.; Keyser, Patrick D.

2012-01-01

We evaluated Canada Warbler (Cardellina canadensis) responses to changes in habitat characteristics (landscape metrics, landcover, and microhabitat features) at multiple spatial scales resulting from timber harvests (clear-cut, heavy partial, and light partial) between 1996 and 2009. Relative abundance of Canada Warblers decreased over time on our West Virginia study area (Wildlife and Ecosystem Research Forest) and within the Appalachian Bird Conservation Region. Initially, relative abundance was greater closer to roads, but as timber harvests became more common, relative abundance became positively associated with amount of light partial harvests at the local scale. Nest survival was 45.6 ± 18.3% during 1996–1998 and 24.9 ± 14.6% during 2007–2009, but did not differ (P = 0.38) between these periods. Areas around nests in 2007–2009 (n = 17) had less intermediate canopy cover and fewer residual trees but more green cover, woody debris, and pole trees than areas around nests in 1996–1998 (n = 10). Successful nests had more low cover, less vertical diversity, more woody debris, more saplings, and greater edge density than failed nests. We found a positive association between relative abundance and all three types of timber harvests and an improvement in habitat through understory development and retention of residual trees. Our research finds preliminary support for use of timber harvests, particularly light partial harvests, as a management tool for Canada Warblers in the southern portion of their range with the need for extended research using treatments and controls to confirm successful management.

Conformational plasticity of DM43, a metalloproteinase inhibitor from Didelphis marsupialis: chemical and pressure-induced equilibrium (un)folding studies.

PubMed

Chapeaurouge, Alex; Martins, Samantha M; Holub, Oliver; Rocha, Surza L G; Valente, Richard H; Neves-Ferreira, Ana G C; Ferreira, Sérgio T; Domont, Gilberto B; Perales, Jonas

2009-10-01

We have investigated the folding of DM43, a homodimeric metalloproteinase inhibitor isolated from the serum of the South American opossum Didelphis marsupialis. Denaturation of the protein induced by GdnHCl (guanidine hydrochloride) was monitored by extrinsic and intrinsic fluorescence spectroscopy. While the equilibrium (un)folding of DM43 followed by tryptophan fluorescence was well described by a cooperative two-state transition, bis-ANS (4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid) fluorescence measurements revealed an intensity maximum at the midpoint of the unfolding transition (2 M GdnHCl), indicating a partially folded intermediate state. We further investigated the DM43 intermediate stabilized at 2 M GdnHCl using size exclusion chromatography. This analysis revealed that the folding intermediate can be best described as partially folded DM43 monomers. Thermodynamic analysis of the GdnHCl-induced denaturation of DM43 revealed Gibbs free-energy changes of 13.57 kcal/mol for dimer dissociation and 1.86 kcal/mol for monomer unfolding, pointing to a critical role of dimerization as a determinant of the structure and stability of this protein. In addition, by using hydrostatic pressure (up to 3.5 kbar) we were able to stabilize partially folded states different from those stabilized in the presence of GdnHCl. Taken together, these results indicate that the conformational plasticity of DM43 could provide this protein with the ability to adapt its conformation to a variety of different environments and biological partners during its biological lifetime.

Partial entrainment of gravel bars during floods

USGS Publications Warehouse

Konrad, Christopher P.; Booth, Derek B.; Burges, Stephen J.; Montgomery, David R.

2002-01-01

Spatial patterns of bed material entrainment by floods were documented at seven gravel bars using arrays of metal washers (bed tags) placed in the streambed. The observed patterns were used to test a general stochastic model that bed material entrainment is a spatially independent, random process where the probability of entrainment is uniform over a gravel bar and a function of the peak dimensionless shear stress τ0* of the flood. The fraction of tags missing from a gravel bar during a flood, or partial entrainment, had an approximately normal distribution with respect to τ0* with a mean value (50% of the tags entrained) of 0.085 and standard deviation of 0.022 (root‐mean‐square error of 0.09). Variation in partial entrainment for a given τ0* demonstrated the effects of flow conditioning on bed strength, with lower values of partial entrainment after intermediate magnitude floods (0.065 < τ0*< 0.08) than after higher magnitude floods. Although the probability of bed material entrainment was approximately uniform over a gravel bar during individual floods and independent from flood to flood, regions of preferential stability and instability emerged at some bars over the course of a wet season. Deviations from spatially uniform and independent bed material entrainment were most pronounced for reaches with varied flow and in consecutive floods with small to intermediate magnitudes.

Starch and the Control of Kernel Number in Maize at Low Water Potentials1

PubMed Central

Zinselmeier, Christopher; Jeong, Byeong-Ryong; Boyer, John S.

1999-01-01

After reproduction is initiated in plants, subsequent reproductive development is sometimes interrupted, which decreases the final number of seeds and fruits. We subjected maize (Zea mays L.) to low water potentials (ψw) that frequently cause this kind of failure. We observed metabolite pools and enzyme activities in the developing ovaries while we manipulated the sugar stream by feeding sucrose (Suc) to the stems. Low ψw imposed for 5 d around pollination allowed embryos to form, but abortion occurred and kernel number decreased markedly. The ovary contained starch that nearly disappeared during this abortion. Analyses showed that all of the intermediates in starch synthesis were depleted. However, when labeled Suc was fed to the stems, label arrived at the ovaries. Solute accumulated and caused osmotic adjustment. Suc accumulated, but other intermediates did not, showing that a partial block in starch synthesis occurred at the first step in Suc utilization. This step was mediated by invertase, which had low activity. Because of the block, Suc feeding only partially prevented starch disappearance and abortion. These results indicate that young embryos abort when the sugar stream is interrupted sufficiently to deplete starch during early ovary development, and this abortion results in a loss of mature seeds and fruits. At low ψw, maintaining the sugar stream partially prevented the abortion, but invertase regulated the synthesis of ovary starch and partially prevented full recovery. PMID:10482657

Partial oxidation of alkanes by dioxiranes formed in situ at low temperature.

PubMed

Yacob, Sara; Caulfield, Michael J; Barckholtz, Timothy A

2018-01-13

Partial oxidation catalysts capable of efficiently operating at low temperatures may limit the over-oxidation of alkane substrates and thereby improve selectivity. This work focuses on examining alkane oxidation using completely metal-free organocatalysts, dioxiranes. The dioxiranes employed here are synthesized by oxidation of a ketone using a terminal oxidant, such as hydrogen peroxide. Our work generates the dioxirane in situ , so that the process can be catalytic with respect to the ketone. To date, we have demonstrated selective partial oxidation of adamantane using ketone catalysts resulting in yields upwards of 60% towards 1-adamantanol with greater than 99% selectivity. Furthermore, we have demonstrated that changing the electrophilic character of the ketone R groups to contain more electron-donating ligands facilitates the dioxirane ring formation and improves overall oxidation yields. Isotopic labelling studies using H 2 18 O 2 show the preferential incorporation of an 18 O label into the parent ketone, providing evidence for a dioxirane intermediate formed in situ The isotopic labelling studies, along with solvent effect studies, suggest the formation of peracetic acid as a reactive intermediate.This article is part of a discussion meeting issue 'Providing sustainable catalytic solutions for a rapidly changing world'. © 2017 The Author(s).

Method for producing metal oxide aerogels

DOEpatents

Tillotson, Thomas M.; Poco, John F.; Hrubesh, Lawrence W.; Thomas, Ian M.

1995-01-01

A two-step hydrolysis-condensation method was developed to form metal oxide aerogels of any density, including densities of less than 0.003g/cm.sup.3 and greater than 0.27g/cm.sup.3. High purity metal alkoxide is reacted with water, alcohol solvent, and an additive to form a partially condensed metal intermediate. All solvent and reaction-generated alcohol is removed, and the intermediate is diluted with a nonalcoholic solvent. The intermediate can be stored for future use to make aerogels of any density. The aerogels are formed by reacting the intermediate with water, nonalcoholic solvent, and a catalyst, and extracting the nonalcoholic solvent directly. The resulting monolithic aerogels are hydrophobic and stable under atmospheric conditions, and exhibit good optical transparency, high clarity, and homogeneity. The aerogels have high thermal insulation capacity, high porosity, mechanical strength and stability, and require shorter gelation times than aerogels formed by conventional methods.

Method for producing metal oxide aerogels

DOEpatents

Tillotson, T.M.; Poco, J.F.; Hrubesh, L.W.; Thomas, I.M.

1995-04-25

A two-step hydrolysis-condensation method was developed to form metal oxide aerogels of any density, including densities of less than 0.003g/cm{sup 3} and greater than 0.27g/cm{sup 3}. High purity metal alkoxide is reacted with water, alcohol solvent, and an additive to form a partially condensed metal intermediate. All solvent and reaction-generated alcohol is removed, and the intermediate is diluted with a nonalcoholic solvent. The intermediate can be stored for future use to make aerogels of any density. The aerogels are formed by reacting the intermediate with water, nonalcoholic solvent, and a catalyst, and extracting the nonalcoholic solvent directly. The resulting monolithic aerogels are hydrophobic and stable under atmospheric conditions, and exhibit good optical transparency, high clarity, and homogeneity. The aerogels have high thermal insulation capacity, high porosity, mechanical strength and stability, and require shorter gelation times than aerogels formed by conventional methods. 8 figs.

Modular heat exchanger

DOEpatents

Giardina, A.R.

1981-03-03

A shell and tube heat exchanger is described having a plurality of individually removable tube bundle modules. A lattice of structural steel forming rectangular openings therein is placed at each end of a cylindrical shell. Longitudinal structural members are placed in the shell between corners of the rectangular openings situated on opposite ends of the shell. Intermediate support members interconnect the longitudinal supports so as to increase the longitudinal supports rigidity. Rectangular parallelepiped tube bundle modules occupy the space defined by the longitudinal supports and end supports and each include a rectangular tube sheet situated on each end of a plurality of tubes extending there through, a plurality of rectangular tube supports located between the tube sheets, and a tube bundle module stiffening structure disposed about the bundle's periphery and being attached to the tube sheets and tube supports. The corners of each tube bundle module have longitudinal framework members which are mateable with and supported by the longitudinal support members. Intermediate support members constitute several lattices, each of which is situated in a plane between the end support members. The intermediate support members constituting the several lattices extend horizontally and vertically between longitudinal supports of adjacent tube module voids. An alternative embodiment for intermediate support members constitute a series of structural plates situated at the corners of the module voids and having recesses therein for receiving the respective longitudinal support members adjacent thereto, protrusions separating the recesses, and a plurality of struts situated between protrusions of adjacent structural plates. 12 figs.

Modular heat exchanger

DOEpatents

Giardina, Angelo R. [Marple Township, Delaware County, PA

1981-03-03

A shell and tube heat exchanger having a plurality of individually removable tube bundle modules. A lattice of structural steel forming rectangular openings therein is placed at each end of a cylindrical shell. Longitudinal structural members are placed in the shell between corners of the rectangular openings situated on opposite ends of the shell. Intermediate support members interconnect the longitudinal supports so as to increase the longitudinal supports rigidity. Rectangular parallelpiped tube bundle moldules occupy the space defined by the longitudinal supports and end supports and each include a rectangular tube sheet situated on each end of a plurality of tubes extending therethrough, a plurality of rectangular tube supports located between the tube sheets, and a tube bundle module stiffening structure disposed about the bundle's periphery and being attached to the tube sheets and tube supports. The corners of each tube bundle module have longitudinal framework members which are mateable with and supported by the longitudinal support members. Intermediate support members constitute several lattice, each of which is situate d in a plane between the end support members. The intermediate support members constituting the several lattice extend horizontally and vertically between longitudinal supports of adjacent tube module voids. An alternative embodiment for intermediate support members constitute a series of structural plates situated at the corners of the module voids and having recesses therein for receiving the respective longitudinal support members adjacent thereto, protrusions separating the recesses, and a plurality of struts situated between protrusions of adjacent structural plates.

The electromagnetic interchange mode in a partially ionized collisional plasma. [spread F region

NASA Technical Reports Server (NTRS)

Hudson, M. K.; Kennel, C. F.

1974-01-01

A collisional electromagnetic dispersion relation is derived from two-fluid theory for the interchange mode coupled to the Alfven, acoustic, drift and entropy modes in a partially ionized plasma. The fundamental electromagnetic nature of the interchange model is noted; coupling to the intermediate Alfven mode is strongly stabilizing for finite k sub z. Both ion viscous and ion-neutral stabilization are included, and it was found that collisions destroy the ion finite Larmor radius cutoff at short perpendicular wavelengths.

Intraspecific Genetic Admixture and the Morphological Diversification of an Estuarine Fish Population Complex

PubMed Central

Legault, Michel

2015-01-01

The North-east American Rainbow smelt (Osmerus mordax) is composed of two glacial races first identified through the spatial distribution of two distinct mtDNA lineages. Contemporary breeding populations of smelt in the St. Lawrence estuary comprise contrasting mixtures of both lineages, suggesting that the two races came into secondary contact in this estuary. The overall objective of this study was to assess the role of intraspecific genetic admixture in the morphological diversification of the estuarine rainbow smelt population complex. The morphology of mixed-ancestry populations varied as a function of the relative contribution of the two races to estuarine populations, supporting the hypothesis of genetic admixture. Populations comprising both ancestral mtDNA races did not exhibit intermediate morphologies relative to pure populations but rather exhibited many traits that exceeded the parental trait values, consistent with the hypothesis of transgressive segregation. Evidence for genetic admixture at the level of the nuclear gene pool, however, provided only partial support for this hypothesis. Variation at nuclear AFLP markers revealed clear evidence of the two corresponding mtDNA glacial races. The admixture of the two races at the nuclear level is only pronounced in mixed-ancestry populations dominated by one of the mtDNA lineages, the same populations showing the greatest degree of morphological diversification and population structure. In contrast, mixed-ancestry populations dominated by the alternate mtDNA lineage showed little evidence of introgression of the nuclear genome, little morphological diversification and little contemporary population genetic structure. These results only partially support the hypothesis of transgressive segregation and may be the result of the differential effects of natural selection acting on admixed genomes from different sources. PMID:25856193

Structure based aggregation studies reveal the presence of helix-rich intermediate during α-Synuclein aggregation

PubMed Central

Ghosh, Dhiman; Singh, Pradeep K.; Sahay, Shruti; Jha, Narendra Nath; Jacob, Reeba S.; Sen, Shamik; Kumar, Ashutosh; Riek, Roland; Maji, Samir K.

2015-01-01

Mechanistic understanding of nucleation dependent polymerization by α-synuclein (α-Syn) into toxic oligomers and amyloids is important for the drug development against Parkinson's disease. However the structural and morphological characterization during nucleation and subsequent fibrillation process of α-Syn is not clearly understood. Using a variety of complementary biophysical techniques monitoring entire pathway of nine different synucleins, we found that transition of unstructured conformation into β-sheet rich fibril formation involves helix-rich intermediates. These intermediates are common for all aggregating synucleins, contain high solvent-exposed hydrophobic surfaces, are cytotoxic to SHSY-5Y cells and accelerate α-Syn aggregation efficiently. A multidimensional NMR study characterizing the intermediate accompanied with site-specific fluorescence study suggests that the N-terminal and central portions mainly participate in the helix-rich intermediate formation while the C-terminus remained in an extended conformation. However, significant conformational transitions occur at the middle and at the C-terminus during helix to β-sheet transition as evident from Trp fluorescence study. Since partial helix-rich intermediates were also observed for other amyloidogenic proteins such as Aβ and IAPP, we hypothesize that this class of intermediates may be one of the important intermediates for amyloid formation pathway by many natively unstructured protein/peptides and represent a potential target for drug development against amyloid diseases. PMID:25784353

[Stakeholder representations of the role of the intermediate level of the DRC health system].

PubMed

Mbeva, Jean Bosco Kahindo; Karemere, Hermès; Schirvel, Carole; Porignon, Denis

2014-01-01

Intermediate health care structures in the DRC were designed during the setting-up of primary health care in a perspective of health district support. This study was designed to describe stakeholder representations of the intermediate level of the DRC health system during the first 30 years of the primary health care system. This case study was based on inductive analysis of data from 27 key informant interviews.. The intermediate level of the health system, lacking sufficient expertise and funding during the 1980s, was confined to inspection and control functions, answering to the central level of the Ministry of health and provincial authorities. Since the 1990s, faced with the pressing demand for support from health district teams, whose self-management had to deal with humanitarian emergencies, the need to integrate vertical programmes, and cope with the logistics of many different actors, the intermediate heath system developed methods and tools to support heath districts. This resulted in a subsidiary model of the intermediate level, the perceived efficacy of which varies according to the province over recent years. The "subsidiary" model of the intermediary health system level seems a good alternative to the "control" model in DRC.

Solvent sensitivity of protein unfolding: dynamical study of chicken villin headpiece subdomain in water-ethanol binary mixture.

PubMed

Ghosh, Rikhia; Roy, Susmita; Bagchi, Biman

2013-12-12

We carry out a series of long atomistic molecular dynamics simulations to study the unfolding of a small protein, chicken villin headpiece (HP-36), in water-ethanol (EtOH) binary mixture. The prime objective of this work is to explore the sensitivity of protein unfolding dynamics toward increasing concentration of the cosolvent and unravel essential features of intermediates formed in search of a dynamical pathway toward unfolding. In water-ethanol binary mixtures, HP-36 is found to unfold partially, under ambient conditions, that otherwise requires temperature as high as ∼600 K to denature in pure aqueous solvent. However, an interesting course of pathway is observed to be followed in the process, guided by the formation of unique intermediates. The first step of unfolding is essentially the separation of the cluster formed by three hydrophobic (phenylalanine) residues, namely, Phe-7, Phe-11, and Phe-18, which constitute the hydrophobic core, thereby initiating melting of helix-2 of the protein. The initial steps are similar to temperature-induced unfolding as well as chemical unfolding using DMSO as cosolvent. Subsequent unfolding steps follow a unique path. As water-ethanol shows composition-dependent anomalies, so do the details of unfolding dynamics. With an increase in cosolvent concentration, different partially unfolded intermediates are found to be formed. This is reflected in a remarkable nonmonotonic composition dependence of several order parameters, including fraction of native contacts and protein-solvent interaction energy. The emergence of such partially unfolded states can be attributed to the preferential solvation of the hydrophobic residues by the ethyl groups of ethanol. We further quantify the local dynamics of unfolding by using a Marcus-type theory.

Geochemistry of the Archean Yellowknife Supergroup

NASA Astrophysics Data System (ADS)

Jenner, G. A.; Fryer, B. J.; McLennan, S. M.

1981-07-01

The Archean Yellowknife Supergroup (Slave Structural Province. Canada) is composed of a thick sequence of supracrustal rocks, which differs from most Archean greenstone belts in that it contains a large proportion ( ~ 80%) of sedimentary rocks. Felsic volcanics of the Banting Formation are characterized by HREE depletion without Eu-anomalies, indicating an origin by small degrees of partial melting of a mafic source, with minor garnet in the residua. Granitic rocks include synkinematic granites [HREE-depleted; low ( 87Sr /86Sr ) I], post-kinematic granites [negative Eu-anomalies, high ( 87Sr /86Sr ) I] and granitic gneisses with REE patterns similar to the post-kinematic granites. Sedimentary rocks (turbidites) of the Burwash and Walsh Formations have similar chemical compositions and were derived from 20% mafic-intermediate volcanics, 55% felsic volcanics and 25% granitic rocks. Jackson Lake Formation lithic wackes can be divided into two groups with Group A derived from 50% mafic-intermediate volcanics and 50% felsic volcanics and Group B, characterized by HREE depletion, derived almost exclusively from felsic volcanics. REE patterns of Yellowknife sedimentary rocks are similar to other Archean sedimentary REE patterns, although they have higher La N/Yb N. These patterns differ significantly from typical post-Archean sedimentary REE patterns, supporting the idea that Archean exposed crust had a different composition than the present day exposed crust.

Study of Intermediate Age (~10-30 Myr) Open Clusters

NASA Astrophysics Data System (ADS)

Olguin, Lorenzo; Michel, Raul; Contreras, Maria; Hernandez, Jesus; Schuster, William; Chavarria-Kleinhenn, Carlos

2013-07-01

We present the study of a sample of intermediate age open clusters (age ~ 10-30 Myr) using optical (UBVRI) and infrared photometric data. Optical photometry was obtained as part of the San Pedro Martir Open Clusters Project (SPM-OCP, Schuster et al. 2007; Michel et al. 2013). Infrared photometry was retrieved from 2MASS public data archive and WISE database. Open clusters included in the SPM-OCP were selected from catalogues presented by Dias et al. (2002) and Froebrich, Scholz & Raftery (2007). One of the main goals of the SPM-OCP is to compile a self-consistent and homogeneous set of cluster fundamental parameters such as reddening, distance, age, and metallicity whenever possible. In this work, we have analyzed a set of 25 clusters from the SPM-OCP with estimated ages between 10 and 30 Myr. Derived fundamental parameters for each cluster in the sample as well as an example of typical color-color and color-magnitude diagrams are presented. Kinematic membership was established by using proper motion data taken from the literature. Based on infrared photometry, we have searched for candidate stars to posses a circumstellar disk within each clusters. For those selected candidates a follow-up spectroscpic study is being carried out. This work was partially supported by UNAM-PAPIIT grant IN-109311.

Computational Analysis of Intra-Ventricular Flow Pattern Under Partial and Full Support of BJUT-II VAD.

PubMed

Zhang, Qi; Gao, Bin; Chang, Yu

2017-02-27

BACKGROUND Partial support, as a novel support mode, has been widely applied in clinical practice and widely studied. However, the precise mechanism of partial support of LVAD in the intra-ventricular flow pattern is unclear. MATERIAL AND METHODS In this study, a patient-specific left ventricular geometric model was reconstructed based on CT data. The intra-ventricular flow pattern under 3 simulated conditions - "heart failure", "partial support", and "full support" - were simulated by using fluid-structure interaction (FSI). The blood flow pattern, wall shear stress (WSS), time-average wall shear stress (TAWSS), oscillatory shear index (OSI), and relative residence time (RRT) were calculated to evaluate the hemodynamic effects. RESULTS The results demonstrate that the intra-ventricular flow pattern is significantly changed by the support level of BJUT-II VAD. The intra-ventricular vortex was enhanced under partial support and was eliminated under full support, and the high OSI and RRT regions changed from the septum wall to the cardiac apex. CONCLUSIONS In brief, the support level of the BJUT-II VAD has significant effects on the intra-ventricular flow pattern. The partial support mode of BJUT-II VAD can enhance the intra-ventricular vortex, while the distribution of high OSI and RRT moved from the septum wall to the cardiac apex. Hence, the partial support mode of BJUT-II VAD can provide more benefit for intra-ventricular flow pattern.

Ambiguities in model-independent partial-wave analysis

NASA Astrophysics Data System (ADS)

Krinner, F.; Greenwald, D.; Ryabchikov, D.; Grube, B.; Paul, S.

2018-06-01

Partial-wave analysis is an important tool for analyzing large data sets in hadronic decays of light and heavy mesons. It commonly relies on the isobar model, which assumes multihadron final states originate from successive two-body decays of well-known undisturbed intermediate states. Recently, analyses of heavy-meson decays and diffractively produced states have attempted to overcome the strong model dependences of the isobar model. These analyses have overlooked that model-independent, or freed-isobar, partial-wave analysis can introduce mathematical ambiguities in results. We show how these ambiguities arise and present general techniques for identifying their presence and for correcting for them. We demonstrate these techniques with specific examples in both heavy-meson decay and pion-proton scattering.

A Concurrent Support Course for Intermediate Algebra

ERIC Educational Resources Information Center

Cooper, Cameron I.

2011-01-01

This article summarizes the creation and implementation of a concurrent support class for TRS 92--Intermediate Algebra, a developmental mathematics course at Fort Lewis College in Durango, Colorado. The concurrent course outlined in this article demonstrates a statistically significant increase in student success rates since its inception.…

Getting into the Jet Stream.

ERIC Educational Resources Information Center

Boggs, Elizabeth M.

1992-01-01

This paper reacts to previous symposium papers (EC 604 155-161) concerning regulations and quality assurance in Intermediate Care Facilities for the Mentally Retarded (ICF/MR). Contributions of the Home and Community Based Services program model, which is seen as a partial solution to overregulation, are highlighted. (DB)

CD44 Is a Negative Cell Surface Marker for Pluripotent Stem Cell Identification during Human Fibroblast Reprogramming

PubMed Central

Vaz, Candida; Tanavde, Vivek; Lakshmipathy, Uma

2014-01-01

Induced pluripotent stem cells (iPSCs) are promising tools for disease research and cell therapy. One of the critical steps in establishing iPSC lines is the early identification of fully reprogrammed colonies among unreprogrammed fibroblasts and partially reprogrammed intermediates. Currently, colony morphology and pluripotent stem cell surface markers are used to identify iPSC colonies. Through additional clonal characterization, we show that these tools fail to distinguish partially reprogrammed intermediates from fully reprogrammed iPSCs. Thus, they can lead to the selection of suboptimal clones for expansion. A subsequent global transcriptome analysis revealed that the cell adhesion protein CD44 is a marker that differentiates between partially and fully reprogrammed cells. Immunohistochemistry and flow cytometry confirmed that CD44 is highly expressed in the human parental fibroblasts used for the reprogramming experiments. It is gradually lost throughout the reprogramming process and is absent in fully established iPSCs. When used in conjunction with pluripotent cell markers, CD44 staining results in the clear identification of fully reprogrammed cells. This combination of positive and negative surface markers allows for easier and more accurate iPSC detection and selection, thus reducing the effort spent on suboptimal iPSC clones. PMID:24416407

Glutamate Induced Thermal Equilibrium Intermediate and Counteracting Effect on Chemical Denaturation of Proteins.

PubMed

Anumalla, Bramhini; Prabhu, N Prakash

2018-01-25

When organisms are subjected to stress conditions, one of their adaptive responses is accumulation of small organic molecules called osmolytes. These osmolytes affect the structure and stability of the biological macromolecules including proteins. The present study examines the effect of a negatively charged amino acid osmolyte, glutamate (Glu), on two model proteins, ribonuclease A (RNase A) and α-lactalbumin (α-LA), which have positive and negative surface charges at pH 7, respectively. These proteins follow two-state unfolding transitions during both heat and chemical induced denaturation processes. The addition of Glu stabilizes the proteins against temperature and induces an early equilibrium intermediate during unfolding. The stability is found to be enthalpy-driven, and the free energy of stabilization is more for α-LA compared to RNase A. The decrease in the partial molar volume and compressibility of both of the proteins in the presence of Glu suggests that the proteins attain a more compact state through surface hydration which could provide a more stable conformation. This is also supported by molecule dynamic simulation studies which demonstrate that the water density around the proteins is increased upon the addition of Glu. Further, the intermediates could be completely destabilized by lower concentrations (∼0.5 M) of guanidinium chloride and salt. However, urea subverts the Glu-induced intermediate formed by α-LA, whereas it only slightly destabilizes in the case of RNase A which has a positive surface charge and could possess charge-charge interactions with Glu. This suggests that, apart from hydration, columbic interactions might also contribute to the stability of the intermediate. Gdm-induced denaturation of RNase A and α-LA in the absence and the presence of Glu at different temperatures was carried out. These results also show the Glu-induced stabilization of both of the proteins; however, all of the unfolding transitions followed two-state transitions during chemical denaturation. The extent of stability exerted by Glu is higher for RNase A at higher temperature, whereas it provides more stability for α-LA at lower temperature. Thus, the experiments indicate that Glu induces a thermal equilibrium intermediate and increases the thermodynamic stability of proteins irrespective of their surface charges. The extent of stability varies between the proteins in a temperature-dependent manner.

77 FR 72920 - Federal Housing Administration (FHA) Section 232 Healthcare Mortgage Insurance Program: Partial...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-07

...This rule amends the regulations governing FHA's Section 232 Healthcare Mortgage Insurance program (Section 232 program) by establishing the criteria and process by which FHA will accept and pay a partial payment of a claim under the FHA mortgage insurance contract. The Section 232 program insures mortgage loans to facilitate the construction, substantial rehabilitation, purchase, and refinancing of nursing homes, intermediate care facilities, board and care homes, and assisted-living facilities. Through acceptance and payment of a partial payment of claim, FHA pays the lender a portion of the unpaid principal balance and recasts a portion of the mortgage under terms and conditions determined by FHA, as an alternative to the lender assigning the entire mortgage to HUD. Partial payment of claim also allows FHA- insured healthcare projects to continue operating and providing services.

Formation of a quinoneimine intermediate of 4-fluoro-N-methylaniline by FMO1: carbon oxidation plus defluorination.

PubMed

Driscoll, James P; Aliagas, Ignacio; Harris, Jennifer J; Halladay, Jason S; Khatib-Shahidi, Sheerin; Deese, Alan; Segraves, Nathaniel; Khojasteh-Bakht, S Cyrus

2010-05-17

Here, we report on the mechanism by which flavin-containing monooxygenase 1 (FMO1) mediates the formation of a reactive intermediate of 4-fluoro-N-methylaniline. FMO1 catalyzed a carbon oxidation reaction coupled with defluorination that led to the formation of 4-N-methylaminophenol, which was a reaction first reported by Boersma et al. (Boersma et al. (1993) Drug Metab. Dispos. 21 , 218 - 230). We propose that a labile 1-fluoro-4-(methylimino)cyclohexa-2,5-dienol intermediate was formed leading to an electrophilic quinoneimine intermediate. The identification of N-acetylcysteine adducts by LC-MS/MS and NMR further supports the formation of a quinoneimine intermediate. Incubations containing stable labeled oxygen (H(2)(18)O or (18)O(2)) and ab initio calculations were performed to support the proposed reaction mechanism.

Microstructural impacts on the electrical properties of copper and titanium substituted bismuth vanadates

NASA Astrophysics Data System (ADS)

Ring, Kevin

In the search for a material that can exceed the performance of YSZ as an ionic oxide conductor at intermediate temperatures (300°C to 600°C) a group of Aurivillius phase ceramics dubbed the BIMEVOX (Bi 2V1-xMexO5.5-delta) family has garnered much attention over the past 20 years. Novel results regarding the influence of microstructure on electrical properties were obtained by non-conventional methods of fabrication and characterization. Approaches included: uniaxial, load assisted sintering, molten salt synthesis, templated grain growth, and the use of ion blocking electrodes to measure the partial electronic conductivity. Molten salt synthesis methods successfully produced high aspect ratio platelets of both BiCuVOx (Bi2V0.9Cu0.1O 5.5-delta) and BiCuTiVOx (Bi2V0.9Cu0.05 Ti0.05O5.5-delta), at a variety of temperatures and times. Uniaxial load assisted sintering (or "hot-forging") when combined with templated grain growth produced high density (rho>95% theoretical) samples of moderate texture (F(00l) up to 29%). Impedance spectroscopy measurements indicated that increased texture and grain size reduce the thermal stability of BiCuVOx below the critical gamma-phase transition temperature. Measurements of total conductivity were made with changing oxygen partial pressure down to 10-4 atm of oxygen between temperatures of 400°C and 550°C. Under those conditions, total conductivity was invariant, confirming published results of operation within the ionic compensated regime. Partial electronic conductivity and electronic transference numbers were estimated by asymmetric DC polarization measurements down to 10-6 atm of oxygen between 500°C and 550°C. The results indicate that the partial pressure of oxygen in normal air is already below the intrinsic minimum of conductivity at 500°C and that electronic conductivity may become significant (te>0.01) no lower than 10-6 atm of oxygen. The culmination of research since its first publication poses uncertainty regarding the longevity of BIMEVOX compounds in long term and intermediate temperature electrochemical devices. The work performed on samples of BiCuVOx corroborates many of the conclusions found in the literature and does not support the use of these formulations as a continuous use electrolyte at temperatures greater than 500°C. Results also indicate that operation at temperatures below 500°C might be possible if the phase stability issues are addressed by tailoring the microstructure or use of dual substitutions, such as BiCuTiVOx.

Dispersion relation for hadronic light-by-light scattering: two-pion contributions

DOE PAGES

Colangelo, Gilberto; Hoferichter, Martin; Procura, Massimiliano; ...

2017-04-27

In our third paper of a series dedicated to a dispersive treatment of the hadronic light-by-light (HLbL) tensor, we derive a partial-wave formulation for two-pion intermediate states in the HLbL contribution to the anomalous magnetic moment of the muon (g - 2) μ, including a detailed discussion of the unitarity relation for arbitrary partial waves. We show that obtaining a final expression free from unphysical helicity partial waves is a subtle issue, which we thoroughly clarify. As a by-product, we obtain a set of sum rules that could be used to constrain future calculations of γ*γ* → ππ. We validate the formalism extensively using the pion-box contribution, defined by two-pion intermediate states with a pion-pole left-hand cut, and demonstrate how the full known result is reproduced when resumming the partial waves. Using dispersive fits to high-statistics data for the pion vector form factor, we provide an evaluation of the full pion box, amore » $$π-box\\atop{μ}$$ =-15.9(2) × 10 -11. As an application of the partial-wave formalism, we present a first calculation of ππ-rescattering effects in HLbL scattering, with γ*γ* → ππ helicity partial waves constructed dispersively using ππ phase shifts derived from the inverse-amplitude method. In this way, the isospin-0 part of our calculation can be interpreted as the contribution of the f0(500) to HLbL scattering in (g - 2) μ. We also argue that the contribution due to charged-pion rescattering implements corrections related to the corresponding pion polarizability and show that these are moderate. Our final result for the sum of pion-box contribution and its S-wave rescattering corrections reads a$$π-box\\atop{μ}$$ + a$$ππ, π-pole LHC\\atop{μ, J=0}$$ = -24(1) × 10 -11.« less

Dispersion relation for hadronic light-by-light scattering: two-pion contributions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colangelo, Gilberto; Hoferichter, Martin; Procura, Massimiliano

In our third paper of a series dedicated to a dispersive treatment of the hadronic light-by-light (HLbL) tensor, we derive a partial-wave formulation for two-pion intermediate states in the HLbL contribution to the anomalous magnetic moment of the muon (g - 2) μ, including a detailed discussion of the unitarity relation for arbitrary partial waves. We show that obtaining a final expression free from unphysical helicity partial waves is a subtle issue, which we thoroughly clarify. As a by-product, we obtain a set of sum rules that could be used to constrain future calculations of γ*γ* → ππ. We validate the formalism extensively using the pion-box contribution, defined by two-pion intermediate states with a pion-pole left-hand cut, and demonstrate how the full known result is reproduced when resumming the partial waves. Using dispersive fits to high-statistics data for the pion vector form factor, we provide an evaluation of the full pion box, amore » $$π-box\\atop{μ}$$ =-15.9(2) × 10 -11. As an application of the partial-wave formalism, we present a first calculation of ππ-rescattering effects in HLbL scattering, with γ*γ* → ππ helicity partial waves constructed dispersively using ππ phase shifts derived from the inverse-amplitude method. In this way, the isospin-0 part of our calculation can be interpreted as the contribution of the f0(500) to HLbL scattering in (g - 2) μ. We also argue that the contribution due to charged-pion rescattering implements corrections related to the corresponding pion polarizability and show that these are moderate. Our final result for the sum of pion-box contribution and its S-wave rescattering corrections reads a$$π-box\\atop{μ}$$ + a$$ππ, π-pole LHC\\atop{μ, J=0}$$ = -24(1) × 10 -11.« less

Discrete structure of an RNA folding intermediate revealed by cryo-electron microscopy.

PubMed

Baird, Nathan J; Ludtke, Steven J; Khant, Htet; Chiu, Wah; Pan, Tao; Sosnick, Tobin R

2010-11-24

RNA folding occurs via a series of transitions between metastable intermediate states. It is unknown whether folding intermediates are discrete structures folding along defined pathways or heterogeneous ensembles folding along broad landscapes. We use cryo-electron microscopy and single-particle image reconstruction to determine the structure of the major folding intermediate of the specificity domain of a ribonuclease P ribozyme. Our results support the existence of a discrete conformation for this folding intermediate.

Association between partial-volume corrected SUVmax and Oncotype DX recurrence score in early-stage, ER-positive/HER2-negative invasive breast cancer.

PubMed

Lee, Su Hyun; Ha, Seunggyun; An, Hyun Joon; Lee, Jae Sung; Han, Wonshik; Im, Seock-Ah; Ryu, Han Suk; Kim, Won Hwa; Chang, Jung Min; Cho, Nariya; Moon, Woo Kyung; Cheon, Gi Jeong

2016-08-01

Oncotype DX, a 21-gene expression assay, provides a recurrence score (RS) which predicts prognosis and the benefit from adjuvant chemotherapy in patients with early-stage, estrogen receptor-positive (ER-positive), and human epidermal growth factor receptor 2-negative (HER2-negative) invasive breast cancer. However, Oncotype DX tests are expensive and not readily available in all institutions. The purpose of this study was to investigate whether metabolic parameters on (18)F-FDG PET/CT are associated with the Oncotype DX RS and whether (18)F-FDG PET/CT can be used to predict the Oncotype DX RS. The study group comprised 38 women with stage I/II, ER-positive/HER2-negative invasive breast cancer who underwent pretreatment (18)F-FDG PET/CT and Oncotype DX testing. On PET/CT, maximum (SUVmax) and average standardized uptake values, metabolic tumor volume, and total lesion glycolysis were measured. Partial volume-corrected SUVmax (PVC-SUVmax) determined using the recovery coefficient method was also evaluated. Oncotype DX RS (0 - 100) was categorized as low (<18), intermediate (18 - 30), or high (≥31). The associations between metabolic parameters and RS were analyzed. Multivariate logistic regression was used to identify significant independent predictors of low versus intermediate-to-high RS. Of the 38 patients, 22 (58 %) had a low RS, 13 (34 %) had an intermediate RS, and 3 (8 %) had a high RS. In the analysis with 38 index tumors, PVC-SUVmax was higher in tumors in patients with intermediate-to-high RS than in those with low RS (5.68 vs. 4.06; P = 0.067, marginally significant). High PVC-SUVmax (≥4.96) was significantly associated with intermediate-to-high RS (odds ratio, OR, 10.556; P = 0.004) in univariate analysis. In multivariate analysis with clinicopathologic factors, PVC-SUVmax ≥4.96 (OR 8.459; P = 0.013) was a significant independent predictor of intermediate-to-high RS. High PVC-SUVmax on (18)F-FDG PET/CT was significantly associated with an intermediate-to-high Oncotype DX RS. PVC metabolic parameters on (18)F-FDG PET/CT can be used to predict the Oncotype DX RS in patients with early-stage, ER-positive/HER2-negative breast cancer.

Mechanism for accurate, protein-assisted DNA annealing by Deinococcus radiodurans DdrB

PubMed Central

Sugiman-Marangos, Seiji N.; Weiss, Yoni M.; Junop, Murray S.

2016-01-01

Accurate pairing of DNA strands is essential for repair of DNA double-strand breaks (DSBs). How cells achieve accurate annealing when large regions of single-strand DNA are unpaired has remained unclear despite many efforts focused on understanding proteins, which mediate this process. Here we report the crystal structure of a single-strand annealing protein [DdrB (DNA damage response B)] in complex with a partially annealed DNA intermediate to 2.2 Å. This structure and supporting biochemical data reveal a mechanism for accurate annealing involving DdrB-mediated proofreading of strand complementarity. DdrB promotes high-fidelity annealing by constraining specific bases from unauthorized association and only releases annealed duplex when bound strands are fully complementary. To our knowledge, this mechanism provides the first understanding for how cells achieve accurate, protein-assisted strand annealing under biological conditions that would otherwise favor misannealing. PMID:27044084

Retention of intermediate polarization states in ferroelectric materials enabling memories for multi-bit data storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Dong; Asadi, Kamal; Blom, Paul W. M.

A homogeneous ferroelectric single crystal exhibits only two remanent polarization states that are stable over time, whereas intermediate, or unsaturated, polarization states are thermodynamically instable. Commonly used ferroelectric materials however, are inhomogeneous polycrystalline thin films or ceramics. To investigate the stability of intermediate polarization states, formed upon incomplete, or partial, switching, we have systematically studied their retention in capacitors comprising two classic ferroelectric materials, viz. random copolymer of vinylidene fluoride with trifluoroethylene, P(VDF-TrFE), and Pb(Zr,Ti)O{sub 3}. Each experiment started from a discharged and electrically depolarized ferroelectric capacitor. Voltage pulses were applied to set the given polarization states. The retention wasmore » measured as a function of time at various temperatures. The intermediate polarization states are stable over time, up to the Curie temperature. We argue that the remarkable stability originates from the coexistence of effectively independent domains, with different values of polarization and coercive field. A domain growth model is derived quantitatively describing deterministic switching between the intermediate polarization states. We show that by using well-defined voltage pulses, the polarization can be set to any arbitrary value, allowing arithmetic programming. The feasibility of arithmetic programming along with the inherent stability of intermediate polarization states makes ferroelectric materials ideal candidates for multibit data storage.« less

29 CFR 1918.31 - Hatch coverings.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 29 Labor 7 2011-07-01 2011-07-01 false Hatch coverings. 1918.31 Section 1918.31 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Working Surfaces § 1918.31 Hatch coverings. (a) No cargo... partially opened intermediate deck unless either the hatch at that deck is sufficiently covered or an...

29 CFR 1918.31 - Hatch coverings.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Hatch coverings. 1918.31 Section 1918.31 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Working Surfaces § 1918.31 Hatch coverings. (a) No cargo... partially opened intermediate deck unless either the hatch at that deck is sufficiently covered or an...

29 CFR 1918.31 - Hatch coverings.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 29 Labor 7 2013-07-01 2013-07-01 false Hatch coverings. 1918.31 Section 1918.31 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Working Surfaces § 1918.31 Hatch coverings. (a) No cargo... partially opened intermediate deck unless either the hatch at that deck is sufficiently covered or an...

29 CFR 1918.31 - Hatch coverings.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 29 Labor 7 2014-07-01 2014-07-01 false Hatch coverings. 1918.31 Section 1918.31 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Working Surfaces § 1918.31 Hatch coverings. (a) No cargo... partially opened intermediate deck unless either the hatch at that deck is sufficiently covered or an...

29 CFR 1918.31 - Hatch coverings.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 29 Labor 7 2012-07-01 2012-07-01 false Hatch coverings. 1918.31 Section 1918.31 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Working Surfaces § 1918.31 Hatch coverings. (a) No cargo... partially opened intermediate deck unless either the hatch at that deck is sufficiently covered or an...

Creative Educational Leadership (A Partial Evaluation).

ERIC Educational Resources Information Center

Kralik, Daniel J.

The purpose of the project was to demonstrate the role and function of the new intermediate school district and to show that it could creatively initiate needed changes in education within three years in Pierce County, Washington. Three specific projects are delineated: (1) guidance training for teachers and administrators; (2) development of…

Computerized algorithms for partial cuts

Treesearch

R.L. Ernst; S.L. Stout

1991-01-01

Stand density, stand structure (diameter distribution), and species composition are all changed by intermediate treatments in forest stands. To use computer stand-growth simulators to assess the effects of different treatments on stand growth and development, users must be able to duplicate silviculturally realistic treatments in the simulator. In this paper, we review...

Partial Immersion Program for Saudi Bilinguals

ERIC Educational Resources Information Center

Alsulami, Sumayyah Qaed

2017-01-01

English is taught as a foreign language in Kingdom of Saudi Arabia. Although the government tries gradually to integrate teaching English in all grades: secondary, intermediate and elementary, learning English is still limited and need more developing. This essay is a brief review about bilingualism in Saudi education. This essay will be divided…

38 CFR 3.350 - Special monthly compensation ratings.

Code of Federal Regulations, 2010 CFR

2010-07-01

... constant inability to communicate by speech or, in the case of a woman veteran, loss of 25% or more of tissue from a single breast or both breasts in combination (including loss by mastectomy or partial... intermediate or next higher rate provisions outlined above, additional single permanent disability or...

Predictive Coding in Area V4: Dynamic Shape Discrimination under Partial Occlusion

PubMed Central

Choi, Hannah; Pasupathy, Anitha; Shea-Brown, Eric

2018-01-01

The primate visual system has an exquisite ability to discriminate partially occluded shapes. Recent electrophysiological recordings suggest that response dynamics in intermediate visual cortical area V4, shaped by feedback from prefrontal cortex (PFC), may play a key role. To probe the algorithms that may underlie these findings, we build and test a model of V4 and PFC interactions based on a hierarchical predictive coding framework. We propose that probabilistic inference occurs in two steps. Initially, V4 responses are driven solely by bottom-up sensory input and are thus strongly influenced by the level of occlusion. After a delay, V4 responses combine both feedforward input and feedback signals from the PFC; the latter reflect predictions made by PFC about the visual stimulus underlying V4 activity. We find that this model captures key features of V4 and PFC dynamics observed in experiments. Specifically, PFC responses are strongest for occluded stimuli and delayed responses in V4 are less sensitive to occlusion, supporting our hypothesis that the feedback signals from PFC underlie robust discrimination of occluded shapes. Thus, our study proposes that area V4 and PFC participate in hierarchical inference, with feedback signals encoding top-down predictions about occluded shapes. PMID:29566355

The effect of coal bed dewatering and partial oxidation on biogenic methane potential

USGS Publications Warehouse

Jones, Elizabeth J.P.; Harris, Steve H.; Barnhart, Elliott P.; Orem, William H.; Clark, Arthur C.; Corum, Margo D.; Kirshtein, Julie D.; Varonka, Matthew S.; Voytek, Mary A.

2013-01-01

Coal formation dewatering at a site in the Powder River Basin was associated with enhanced potential for secondary biogenic methane determined by using a bioassay. We hypothesized that dewatering can stimulate microbial activity and increase the bioavailability of coal. We analyzed one dewatered and two water-saturated coals to examine possible ways in which dewatering influences coal bed natural gas biogenesis by looking at differences with respect to the native coal microbial community, coal-methane organic intermediates, and residual coal oxidation potential. Microbial biomass did not increase in response to dewatering. Small Subunit rRNA sequences retrieved from all coals sampled represented members from genera known to be aerobic, anaerobic and facultatively anaerobic. A Bray Curtis similarity analysis indicated that the microbial communities in water-saturated coals were more similar to each other than to the dewatered coal, suggesting an effect of dewatering. There was a higher incidence of long chain and volatile fatty acid intermediates in incubations of the dewatered coal compared to the water-saturated coals, and this could either be due to differences in microbial enzymatic activities or to chemical oxidation of the coal associated with O2 exposure. Dilute H2O2 treatment of two fractions of structural coal (kerogen and bitumen + kerogen) was used as a proxy for chemical oxidation by O2. The dewatered coal had a low residual oxidation potential compared to the water-saturated coals. Oxidation with 5% H2O2 did increase the bioavailability of structural coal, and the increase in residual oxidation potential in the water saturated coals was approximately equivalent to the higher methanogenic potential measured in the dewatered coal. Evidence from this study supports the idea that coal bed dewatering could stimulate biogenic methanogenesis through partial oxidation of the structural organics in coal once anaerobic conditions are restored.

Patient goal setting as a method for program improvement/development in partial hospitalization programs.

PubMed

Gates, A

1991-12-01

Data were collected from a study of 49 patients in 1990 and 106 patients in 1991 admitted into Country View Treatment Center and Green Country Counseling Center. Country View is a 30-bed chemical dependency residential center operating under St. John Medical Center in Tulsa, Oklahoma. Green Country is an evening partial hospital chemical dependency program operating under St. John Medical Center in Tulsa, Oklahoma, The tools used in this study were the Country View Patient Self-Reporting Questionnaire, the global Rating Scale, and the Model of Recovering Alcoholics Behavior Stages and Goal Setting (Wing, 1990). These assessments were specifically designed to measure the patient's perceptions of goal setting and the patient's perspective on treatment outcome. The study outcome resulted in program improvement (Green Country evening partial hospital program) and the development of the Country View Substance Abuse Intermediate Link (SAIL) Program (day partial hospital).

Absolute total and partial dissociative cross sections of pyrimidine at electron and proton intermediate impact velocities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wolff, Wania, E-mail: wania@if.ufrj.br; Luna, Hugo; Sigaud, Lucas

Absolute total non-dissociative and partial dissociative cross sections of pyrimidine were measured for electron impact energies ranging from 70 to 400 eV and for proton impact energies from 125 up to 2500 keV. MOs ionization induced by coulomb interaction were studied by measuring both ionization and partial dissociative cross sections through time of flight mass spectrometry and by obtaining the branching ratios for fragment formation via a model calculation based on the Born approximation. The partial yields and the absolute cross sections measured as a function of the energy combined with the model calculation proved to be a useful toolmore » to determine the vacancy population of the valence MOs from which several sets of fragment ions are produced. It was also a key point to distinguish the dissociation regimes induced by both particles. A comparison with previous experimental results is also presented.« less

Partially oxidized iridium clusters within dendrimers: size-controlled synthesis and selective hydrogenation of 2-nitrobenzaldehyde

NASA Astrophysics Data System (ADS)

Higaki, Tatsuya; Kitazawa, Hirokazu; Yamazoe, Seiji; Tsukuda, Tatsuya

2016-06-01

Iridium clusters nominally composed of 15, 30 or 60 atoms were size-selectively synthesized within OH-terminated poly(amidoamine) dendrimers of generation 6. Spectroscopic characterization revealed that the Ir clusters were partially oxidized. All the Ir clusters efficiently converted 2-nitrobenzaldehyde to anthranil and 2-aminobenzaldehyde under atmospheric hydrogen at room temperature in toluene via selective hydrogenation of the NO2 group. The selectivity toward 2-aminobenzaldehyde over anthranil was improved with the reduction of the cluster size. The improved selectivity is ascribed to more efficient reduction than intramolecular heterocyclization of a hydroxylamine intermediate on smaller clusters that have a higher Ir(0)-phase population on the surface.Iridium clusters nominally composed of 15, 30 or 60 atoms were size-selectively synthesized within OH-terminated poly(amidoamine) dendrimers of generation 6. Spectroscopic characterization revealed that the Ir clusters were partially oxidized. All the Ir clusters efficiently converted 2-nitrobenzaldehyde to anthranil and 2-aminobenzaldehyde under atmospheric hydrogen at room temperature in toluene via selective hydrogenation of the NO2 group. The selectivity toward 2-aminobenzaldehyde over anthranil was improved with the reduction of the cluster size. The improved selectivity is ascribed to more efficient reduction than intramolecular heterocyclization of a hydroxylamine intermediate on smaller clusters that have a higher Ir(0)-phase population on the surface. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01460g

Physiology and growth of advance Picea rubens and Abies balsamea regeneration following different canopy openings.

PubMed

Dumais, Daniel; Prévost, Marcel

2014-02-01

We examined the ecophysiology and growth of 0.3-1.3 m tall advance red spruce (Picea rubens Sarg.) and balsam fir (Abies balsamea [L.] Mill.) regeneration during a 5-year period following the application of different harvest types producing three sizes of canopy openings: (i) small gaps (<100 m(2) in area; SMA) created by partial uniform single-tree harvest; (ii) irregular gaps of intermediate size (100-300 m(2); INT) created by group-selection harvest (removal of groups of trees, mainly balsam fir, with uniform partial removal between groups); and (iii) large circular gaps (700 m(2); LAR) created by patch-selection harvest (removal of trees in 30-m diameter circular areas with uniform partial removal between gaps). An unharvested control (CON) was monitored for comparison. At the ecophysiological level, we mainly found differences in light-saturated photosynthesis of red spruce and specific leaf area of balsam fir among treatments. Consequently, we observed good height growth of both species in CON and INT, but fir surpassed spruce in SMA and LAR. Results suggest that intermediate 100-300 m(2) irregular openings create microenvironmental conditions that may promote short-term ecophysiology and growth of red spruce, allowing the species to compete with balsam fir advance regeneration. Finally, results observed for spruce in large 700-m(2) openings confirm its inability to grow as rapidly as fir in comparable open conditions.

Partially filled intermediate band of Cr-doped GaN films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sonoda, S.

2012-05-14

We investigated the band structure of sputtered Cr-doped GaN (GaCrN) films using optical absorption, photoelectron yield spectroscopy, and charge transport measurements. It was found that an additional energy band is formed in the intrinsic band gap of GaN upon Cr doping, and that charge carriers in the material move in the inserted band. Prototype solar cells showed enhanced short circuit current and open circuit voltage in the n-GaN/GaCrN/p-GaN structure compared to the GaCrN/p-GaN structure, which validates the proposed concept of an intermediate-band solar cell.

[Supporting the intermediate level of health care in urban health areas in Kinshasa (1995-2005), DR Congo].

PubMed

Mbeva, Jean-Bosco Kahindo; Schirvel, Carole; Karemere, Hermès; Porignon, Denis

2012-06-08

As a result of the decentralization of health systems, some countries have introduced intermediate (provincial) levels in their public health system. This paper presents the results of a case study conducted in Kinshasa on health system decentralization. The study identified a shift from a focus on regulation compliance assessment to an emphasis on health system coordination and health district support. It also highlighted the emergence of a?managerial (as opposed to a bureaucratic) approach to health district support. The performance of health districts in terms of health care coverage and health service use were also found to have improved. The results highlight the importance of intermediate levels in?the health care system and the value of a more organic and managerial rationality in supporting health districts faced with the complexity of urban environments and the integration of specialized multi-partner programs and interventions.

The thermal properties of beeswaxes: unexpected findings.

PubMed

Buchwald, Robert; Breed, Michael D; Greenberg, Alan R

2008-01-01

Standard melting point analyses only partially describe the thermal properties of eusocial beeswaxes. Differential scanning calorimetry (DSC) revealed that thermal phase changes in wax are initiated at substantially lower temperatures than visually observed melting points. Instead of a sharp, single endothermic peak at the published melting point of 64 degrees C, DSC analysis of Apis mellifera Linnaeus wax yielded a broad melting curve that showed the initiation of melting at approximately 40 degrees C. Although Apis beeswax retained a solid appearance at these temperatures, heat absorption and initiation of melting could affect the structural characteristics of the wax. Additionally, a more complete characterization of the thermal properties indicated that the onset of melting, melting range and heat of fusion of beeswaxes varied significantly among tribes of social bees (Bombini, Meliponini, Apini). Compared with other waxes examined, the relatively malleable wax of bumblebees (Bombini) had the lowest onset of melting and lowest heat of fusion but an intermediate melting temperature range. Stingless bee (Meliponini) wax was intermediate between bumblebee and honeybee wax (Apini) in heat of fusion, but had the highest onset of melting and the narrowest melting temperature range. The broad melting temperature range and high heat of fusion in the Apini may be associated with the use of wax comb as a free-hanging structural material, while the Bombini and Meliponini support their wax structures with exogenous materials.

Mechanistic studies on the Pd-catalyzed vinylation of aryl halides with vinylalkoxysilanes in water: the effect of the solvent and NaOH promoter.

PubMed

Gordillo, Alvaro; Ortuño, Manuel A; López-Mardomingo, Carmen; Lledós, Agustí; Ujaque, Gregori; de Jesús, Ernesto

2013-09-18

The mechanism of the Pd-catalyzed vinylation of aryl halides with vinylalkoxysilanes in water has been studied using different catalytic precursors. The NaOH promoter converts the initial vinylalkoxysilane into a highly reactive water-soluble vinylsilanolate species. Similarly, deuterium-labeling experiments have shown that, irrespective of the catalytic precursor used, vinylation occurs exclusively at the CH vinylic functionality via a Heck reaction and not at the C-Si bond via a Hiyama cross-coupling. The involvement of a Heck mechanism is interpreted in terms of the reduced nucleophilicity of the base in water, which disfavors the transmetalation step. The Heck product (β-silylvinylarene) undergoes partial desilylation, with formation of a vinylarene, by three different routes: (a) hydrolytic desilylation by the aqueous solvent (only at high temperature); (b) transmetalation of the silyl olefin on the PdH Heck intermediate followed by reductive elimination of vinylarene; (c) reinsertion of the silyl olefin into the PdH bond of the Heck intermediate followed by β-Si syn-elimination. Both the Hiyama and Heck catalytic cycles and desilylation mechanisms b and c have been computationally evaluated for the [Pd(en)Cl2] precursor in water as solvent. The calculated Gibbs energy barriers support the reinsertion route proposed on the basis of the experimental results.

V-doped SnS2: a new intermediate band material for a better use of the solar spectrum.

PubMed

Wahnón, Perla; Conesa, José C; Palacios, Pablo; Lucena, Raquel; Aguilera, Irene; Seminovski, Yohanna; Fresno, Fernando

2011-12-07

Intermediate band materials can boost photovoltaic efficiency through an increase in photocurrent without photovoltage degradation thanks to the use of two sub-bandgap photons to achieve a full electronic transition from the valence band to the conduction band of a semiconductor structure. After having reported in previous works several transition metal-substituted semiconductors as able to achieve the electronic structure needed for this scheme, we propose at present carrying out this substitution in sulfides that have bandgaps of around 2.0 eV and containing octahedrally coordinated cations such as In or Sn. Specifically, the electronic structure of layered SnS(2) with Sn partially substituted by vanadium is examined here with first principles quantum methods and seen to give favourable characteristics in this respect. The synthesis of this material in nanocrystalline powder form is then undertaken and achieved using solvothermal chemical methods. The insertion of vanadium in SnS(2) is found to produce an absorption spectrum in the UV-Vis-NIR range that displays a new sub-bandgap feature in agreement with the quantum calculations. A photocatalytic reaction-based test verifies that this sub-bandgap absorption produces highly mobile electrons and holes in the material that may be used for the solar energy conversion, giving experimental support to the quantum calculations predictions.

An environmental stress model correctly predicts unimodal trends in overall species richness and diversity along intertidal elevation gradients

NASA Astrophysics Data System (ADS)

Zwerschke, Nadescha; Bollen, Merle; Molis, Markus; Scrosati, Ricardo A.

2013-12-01

Environmental stress is a major factor structuring communities. An environmental stress model (ESM) predicts that overall species richness and diversity should follow a unimodal trend along the full stress gradient along which assemblages from a regional biota can occur (not to be confused with the intermediate disturbance hypothesis, which makes predictions only for basal species along an intermediate-to-high stress range). Past studies could only provide partial support for ESM predictions because of the limited stress range surveyed or a low sampling resolution. In this study, we measured overall species richness and diversity (considering all seaweeds and invertebrates) along the intertidal elevation gradient on two wave-sheltered rocky shores from Helgoland Island, on the NE Atlantic coast. In intertidal habitats, tides cause a pronounced gradient of increasing stress from low to high elevations. We surveyed up to nine contiguous elevation zones between the lowest intertidal elevation (low stress) and the high intertidal boundary (high stress). Nonlinear regression analyses revealed that overall species richness and diversity followed unimodal trends across elevations on the two studied shores. Therefore, our study suggests that the ESM might constitute a useful tool to predict local richness and diversity as a function of environmental stress. Performing tests on other systems (marine as well as terrestrial) should help to refine the model.

Photorespiration maintains carbon recycling efficiency at low irradiance despite impaired glycolate/glycerate antiport or hydroxypyruvate reduction

USDA-ARS?s Scientific Manuscript database

Photorespiration partially recycles fixed carbon that would otherwise be lost following the oxygenation reaction of Ribulose, 1-5, carboxylase oxygenase (Rubisco) and significantly reduces net photosynthesis in C3 plants. The recycling of photorespiratory C2 to C3 intermediates is not perfectly effi...

Purification, characterization, and bioinformatics studies of phosphatidic acid phosphohydrolase from Lagenaria siceraria

USDA-ARS?s Scientific Manuscript database

Phosphatidic acid phosphohydrolase (PAP), EC 3.1.3.4, is the penultimate step in the Kennedy pathway of triacyl glycerol (TAG) synthesis leading to the formation of diacyl glycerol (DAG), which is a key intermediate in TAG synthesis. We partially purified a soluble PAP from mid maturing seeds of bot...

Knee contact forces and lower extremity support moments during running in young individuals post-partial meniscectomy.

PubMed

Willy, R W; Bigelow, M A; Kolesar, A; Willson, J D; Thomas, J S

2017-01-01

While partial meniscectomy results in a compromised tibiofemoral joint, little is known regarding tibiofemoral joint loading during running in individuals who are post-partial meniscectomy. It was hypothesized that individuals post-partial meniscectomy would run with a greater hip support moment, yielding reduced peak knee extension moments and reduced tibiofemoral joint contact forces. 3-D Treadmill running mechanics were evaluated in 23 athletic individuals post-partial meniscectomy (37.5 ± 19.0 months post-partial meniscectomy) and 23 matched controls. Bilateral hip, knee and ankle contributions to the total support moment and the peak knee extension moment were calculated. A musculoskeletal model estimated peak and impulse tibiofemoral joint contact forces. Knee function was quantified with the Knee injury and Osteoarthritis Outcome Score (KOOS). During running, the partial meniscectomy group had a greater hip support moment (p = 0.002) and a reduced knee support moment (p < 0.001) relative to the total support moment. This movement pattern was associated with a 14.5 % reduction (p = 0.019) in the peak knee extension moment. Despite these differences, there were no significant group differences in peak or impulse tibiofemoral joint contact forces. Lower KOOS Quality of Life scores were associated with greater hip support moment (p = 0.004, r = -0.58), reduced knee support moment (p = 0.006, r = 0.55) and reduced peak knee extension moment (p = 0.01, r = 0.52). Disordered running mechanics are present long term post-partial meniscectomy. A coordination strategy that shifts a proportion of the total support moment away from the knee to the hip reduces the peak knee extension moment, but does not equate to reduced tibiofemoral joint contact forces during running in individuals post-partial meniscectomy. III.

Mechanical and Metallurgical Evolution of Stainless Steel 321 in a Multi-step Forming Process

NASA Astrophysics Data System (ADS)

Anderson, M.; Bridier, F.; Gholipour, J.; Jahazi, M.; Wanjara, P.; Bocher, P.; Savoie, J.

2016-04-01

This paper examines the metallurgical evolution of AISI Stainless Steel 321 (SS 321) during multi-step forming, a process that involves cycles of deformation with intermediate heat treatment steps. The multi-step forming process was simulated by implementing interrupted uniaxial tensile testing experiments. Evolution of the mechanical properties as well as the microstructural features, such as twins and textures of the austenite and martensite phases, was studied as a function of the multi-step forming process. The characteristics of the Strain-Induced Martensite (SIM) were also documented for each deformation step and intermediate stress relief heat treatment. The results indicated that the intermediate heat treatments considerably increased the formability of SS 321. Texture analysis showed that the effect of the intermediate heat treatment on the austenite was minor and led to partial recrystallization, while deformation was observed to reinforce the crystallographic texture of austenite. For the SIM, an Olson-Cohen equation type was identified to analytically predict its formation during the multi-step forming process. The generated SIM was textured and weakened with increasing deformation.

Effects of the impurity-host interactions on the nonradiative processes in ZnS:Cr

NASA Astrophysics Data System (ADS)

Tablero, C.

2010-11-01

There is a great deal of controversy about whether the behavior of an intermediate band in the gap of semiconductors is similar or not to the deep-gap levels. It can have significant consequences, for example, on the nonradiative recombination. In order to analyze the behavior of an intermediate band, we have considered the effect of the inward and outward displacements corresponding to breathing and longitudinal modes of Cr-doped ZnS and on the charge density for different processes involved in the nonradiative recombination using first-principles. This metal-doped zinc chalcogenide has a partially filled band within the host semiconductor gap. In contrast to the properties exhibited by deep-gap levels in other systems, we find small variations in the equilibrium configurations, forces, and electronic density around the Cr when the nonradiative recombination mechanisms modify the intermediate band charge. The charge density around the impurity is equilibrated in response to the perturbations in the equilibrium nuclear configuration and the charge of the intermediate band. The equilibration follows a Le Chatelier principle through the modification of the contribution from the impurity to the intermediate band and to the valence band. The intermediate band introduced by Cr in ZnS for the concentrations analyzed makes the electronic capture difficult and later multiphonon emission in the charge-transfer processes, in accordance with experimental results.

Intermediate-depth earthquakes within young Cocos plate beneath Central Mexico: A hypothesis test for dehydration embrittlement and shear instability

NASA Astrophysics Data System (ADS)

Song, T.

2010-12-01

Subducting slab undergoes a series of dehydration reactions on their ways into the mantle and these processes are responsible for transporting water, recycling volatiles and chemical elements in arc magmas. It is generally accepted that the SOC is hydrated. However, it is not clear if subducting oceanic mantle (SOM) is hydrated and how deep the hydration is. Seismic refraction studies found that normal-fault type faulting can extend 12-20 km deep into the interior of the slab off Nicaragua, suggesting deep hydration of the SOM. Seismic refraction studies also found that the uppermost SOM is seismically slow and is partially serpentinized. The fluids released from dehydration inside the SOM can reduce the normal stress locally and facilitate the occurrences of intra-slab events through dehydration embrittlement and hydraulic fracture. It has been suggested that the dehydration of antigorite at about 600C is particularly important in facilitating the lower plane of the double seismic zone. To link the dehydration process to the occurrences of intra-slab events, it is critical to clarify where these events are located, either located at the dehydration boundary or in the neighborhood rocks. However, if the SOM is anhydrous, other mechanism, such as shear instabilities, has to be invoked to explain the occurrences of intermediate-depth intraslab earthquakes. Here I discuss locations of intermediate-depth intraslab earthquakes in Central Mexico subduction zone, where young Cocos plate subducts beneath North America plate. Recent studies involving local converted wave modeling and receiver function analysis indicate the presence of an ultra-slow velocity layer (USL) of about 3 km thick, likely an over-pressured upper oceanic crust. Most events display anomalously large converted SP waves that are 2-2.5 secs after direct P waves and finite difference modeling converge the location of these events about 9 km below the lower boundary USL. With a lower oceanic crust of about 3-5 km estimated from receiver function, these intermediate-depth earthquakes are about 6 km inside the SOM. There is no clear evidence yet indicating the presence of a partially serpentinized layer in such a young plate (10-15 Ma). Further waveform modeling is undertaken to explore the presence of such a partially serpentinized layer.

Hyperthermophile Protein Behavior: Partially-Structured Conformations of Pyrococcus furiosus Rubredoxin Monomers Generated through Forced Cold-Denaturation and Refolding

PubMed Central

Ahmed, Shubbir; Guptasarma, Purnananda

2014-01-01

Some years ago, we showed that thermo-chemically denatured, partially-unfolded forms of Pyrococcus furiosus triosephosphateisomerase (PfuTIM) display cold-denaturation upon cooling, and heat-renaturation upon reheating, in proportion with the extent of initial partial unfolding achieved. This was the first time that cold-denaturation was demonstrated for a hyperthermophile protein, following unlocking of surface salt bridges. Here, we describe the behavior of another hyperthermophile protein, the small, monomeric, 53 residues-long rubredoxin from Pyrococcus furiosus (PfRd), which is one of the most thermostable proteins known to man. Like PfuTIM, PfRd too displays cold-denaturation after initial thermo-chemical perturbation, however, with two differences: (i) PfRd requires considerably higher temperatures as well as higher concentrations of guanidium hydrochloride (Gdm.HCl) than PfuTIM; (ii) PfRd's cold-denaturation behavior during cooling after thermo-chemical perturbation is incompletely reversible, unlike PfuTIM's, which was clearly reversible (from each different conformation generated). Differential cold-denaturation treatments allow PfRd to access multiple partially-unfolded states, each of which is clearly highly kinetically-stable. We refer to these as ‘Trishanku’ unfolding intermediates (or TUIs). Fascinatingly, refolding of TUIs through removal of Gdm.HCl generates multiple partially-refolded, monomeric, kinetically-trapped, non-native ‘Trishanku’ refolding intermediates (or TRIs), which differ from each other and from native PfRd and TUIs, in structural content and susceptibility to proteolysis. We find that the occurrence of cold denaturation and observations of TUI and TRI states is contingent on the oxidation status of iron, with redox agents managing to modulate the molecule's behavior upon gaining access to PfRd's iron atom. Mass spectrometric examination provides no evidence of the formation of disulfide bonds, but other experiments suggest that the oxidation status of iron (and its extent of burial) together determine whether or not PfRd shows cold denaturation, and also whether redox agents are able to modulate its behavior. PMID:24603413

Effects of Catalytic Action and Ligand Binding on Conformational Ensembles of Adenylate Kinase.

PubMed

Onuk, Emre; Badger, John; Wang, Yu Jing; Bardhan, Jaydeep; Chishti, Yasmin; Akcakaya, Murat; Brooks, Dana H; Erdogmus, Deniz; Minh, David D L; Makowski, Lee

2017-08-29

Crystal structures of adenylate kinase (AdK) from Escherichia coli capture two states: an "open" conformation (apo) obtained in the absence of ligands and a "closed" conformation in which ligands are bound. Other AdK crystal structures suggest intermediate conformations that may lie on the transition pathway between these two states. To characterize the transition from open to closed states in solution, X-ray solution scattering data were collected from AdK in the apo form and with progressively increasing concentrations of five different ligands. Scattering data from apo AdK are consistent with scattering predicted from the crystal structure of AdK in the open conformation. In contrast, data from AdK samples saturated with Ap5A do not agree with that calculated from AdK in the closed conformation. Using cluster analysis of available structures, we selected representative structures in five conformational states: open, partially open, intermediate, partially closed, and closed. We used these structures to estimate the relative abundances of these states for each experimental condition. X-ray solution scattering data obtained from AdK with AMP are dominated by scattering from AdK in the open conformation. For AdK in the presence of high concentrations of ATP and ADP, the conformational ensemble shifts to a mixture of partially open and closed states. Even when AdK is saturated with Ap5A, a significant proportion of AdK remains in a partially open conformation. These results are consistent with an induced-fit model in which the transition of AdK from an open state to a closed state is initiated by ATP binding.

Efficacy of robust optimization plan with partial-arc VMAT for photon volumetric-modulated arc therapy: A phantom study.

PubMed

Miura, Hideharu; Ozawa, Shuichi; Nagata, Yasushi

2017-09-01

This study investigated position dependence in planning target volume (PTV)-based and robust optimization plans using full-arc and partial-arc volumetric modulated arc therapy (VMAT). The gantry angles at the periphery, intermediate, and center CTV positions were 181°-180° (full-arc VMAT) and 181°-360° (partial-arc VMAT). A PTV-based optimization plan was defined by 5 mm margin expansion of the CTV to a PTV volume, on which the dose constraints were applied. The robust optimization plan consisted of a directly optimized dose to the CTV under a maximum-uncertainties setup of 5 mm. The prescription dose was normalized to the CTV D 99% (the minimum relative dose that covers 99% of the volume of the CTV) as an original plan. The isocenter was rigidly shifted at 1 mm intervals in the anterior-posterior (A-P), superior-inferior (S-I), and right-left (R-L) directions from the original position to the maximum-uncertainties setup of 5 mm in the original plan, yielding recalculated dose distributions. It was found that for the intermediate and center positions, the uncertainties in the D 99% doses to the CTV for all directions did not significantly differ when comparing the PTV-based and robust optimization plans (P > 0.05). For the periphery position, uncertainties in the D 99% doses to the CTV in the R-L direction for the robust optimization plan were found to be lower than those in the PTV-based optimization plan (P < 0.05). Our study demonstrated that a robust optimization plan's efficacy using partial-arc VMAT depends on the periphery CTV position. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Effect of wellbore storage and finite thickness skin on flow to a partially penetrating well in a phreatic aquifer

NASA Astrophysics Data System (ADS)

Pasandi, M.; Samani, N.; Barry, D. A.

2008-02-01

An analytical model is presented for the analysis of constant flux tests conducted in a phreatic aquifer having a partially penetrating well with a finite thickness skin. The solution is derived in the Laplace transform domain for the drawdown in the pumping well, skin and formation regions. The time-domain solution in terms of the aquifer drawdown is then obtained from the numerical inversion of the Laplace transform and presented as dimensionless drawdown-time curves. The derived solution is used to investigate the effects of the hydraulic conductivity contrast between the skin and formation, in addition to wellbore storage, skin thickness, delayed yield, partial penetration and distance to the observation well. The results of the developed solution were compared with those from an existing solution for the case of an infinitesimally thin skin. The latter solution can never approximate that for the developed finite skin. Dimensionless drawdown-time curves were compared with the other published results for a confined aquifer. Positive skin effects are reflected in the early time and disappear in the intermediate and late time aquifer responses. But in the case of negative skin this is reversed and the negative skin also tends to disguise the wellbore storage effect. A thick negative skin lowers the overall drawdown in the aquifer and leads to more persistent delayed drainage. Partial penetration increases the drawdown in the case of a positive skin; however its effect is masked by the negative skin. The influence of a negative skin is pronounced over a broad range of radial distances. At distant observation points the influence of a positive skin is too small to be reflected in early and intermediate time pumping test data and consequently the type curve takes its asymptotic form.

Enhancement of oxidative electrocatalytic properties of platinum nanoparticles by supporting onto mixed WO3/ZrO2 matrix

NASA Astrophysics Data System (ADS)

Rutkowska, Iwona A.; Wadas, Anna; Kulesza, Pawel J.

2016-12-01

Nanostructured mixed metal (W, Zr) oxide matrices (in a form of layered intercalated films of WO3 and ZrO2) are considered here for supporting and activating catalytic platinum nanoparticles toward electrooxidation of ethanol. Remarkable increases of electrocatalytic (voltammetric, chronoamperometric) currents measured in 0.5 mol dm-3 H2SO4 (containing 0.5 mol dm-3 ethanol) have been observed. Comparison has been made to the behavior of methanol and acetaldehyde under analogous conditions. The enhancement effects are interpreted in terms of specific interactions between platinum nanoparticles and the metal oxide species, high acidity of the mixed oxide sites, as well as high population of surface hydroxyl groups and high mobility of protons existing in close vicinity of Pt catalytic sites. The metal oxide nanostructures are expected to interact competitively (via the surface hydroxyl groups) with adsorbates of the undesirable reaction intermediates, including CO, facilitating their desorption ("third body effect"), or even oxidative removal (e.g., of CO to CO2). The fact that the partially reduced tungsten oxide (HxWO3) component is characterized by fast electron transfers coupled to proton displacements tends to improve the overall charge propagation at the electrocatalytic interface.

Removable partial denture supported by implants with prefabricated telescopic abutments - a case report.

PubMed

Kumar, Lalit; Sehgal, Komal

2014-06-01

Implants have been designed to rehabilitate edentulous patients with fixed prosthesis or implant supported overdentures. Implant-supported single crowns and fixed partial dentures have become successful treatment alternatives to removable and fixed partial dentures. However, it is common to have clinical situations which make it impossible to use conventional as well as implant supported fixed partial dentures. The implant supported removable partial dentures can be a treatment modality that offers the multitude of benefits of implant-based therapy-biologic, biomechanical, social, and psychological to such patients. The aim of this article is to present a case report describing the fabrication and advantages of removable partial denture supported by teeth and implants for a patient with long edentulous span. The patient was satisfied with his dentures in terms of function and aesthetics. Regular follow-up visits over a period of three years revealed that the periodontal condition of remaining natural dentition and peri-implant conditions were stable. There was no evidence of excessive residual ridge resorption or mobility of the teeth, nor were any visible changes in the bone levels of the natural teeth or implants noted on radiographs.

The ARES High-level Intermediate Representation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moss, Nicholas David

The LLVM intermediate representation (IR) lacks semantic constructs for depicting common high-performance operations such as parallel and concurrent execution, communication and synchronization. Currently, representing such semantics in LLVM requires either extending the intermediate form (a signi cant undertaking) or the use of ad hoc indirect means such as encoding them as intrinsics and/or the use of metadata constructs. In this paper we discuss a work in progress to explore the design and implementation of a new compilation stage and associated high-level intermediate form that is placed between the abstract syntax tree and when it is lowered to LLVM's IR. Thismore » highlevel representation is a superset of LLVM IR and supports the direct representation of these common parallel computing constructs along with the infrastructure for supporting analysis and transformation passes on this representation.« less

Role of Intermediate Filaments in Vesicular Traffic.

PubMed

Margiotta, Azzurra; Bucci, Cecilia

2016-04-25

Intermediate filaments are an important component of the cellular cytoskeleton. The first established role attributed to intermediate filaments was the mechanical support to cells. However, it is now clear that intermediate filaments have many different roles affecting a variety of other biological functions, such as the organization of microtubules and microfilaments, the regulation of nuclear structure and activity, the control of cell cycle and the regulation of signal transduction pathways. Furthermore, a number of intermediate filament proteins have been involved in the acquisition of tumorigenic properties. Over the last years, a strong involvement of intermediate filament proteins in the regulation of several aspects of intracellular trafficking has strongly emerged. Here, we review the functions of intermediate filaments proteins focusing mainly on the recent knowledge gained from the discovery that intermediate filaments associate with key proteins of the vesicular membrane transport machinery. In particular, we analyze the current understanding of the contribution of intermediate filaments to the endocytic pathway.

Prevalence and Axis I Comorbidity of Full and Partial Posttraumatic Stress Disorder in the United States: Results from Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions

PubMed Central

Pietrzak, Robert H.; Goldstein, Risë B.; Southwick, Steven M.; Grant, Bridget F.

2010-01-01

The present study used data from the Wave 2 National Epidemiologic Survey on Alcohol and Related Conditions (n=34,653) to examine lifetime Axis I psychiatric comorbidity of posttraumatic stress disorder (PTSD) in a nationally representative sample of U.S. adults. Lifetime prevalences±standard errors of PTSD and partial PTSD were 6.4%±0.18 and 6.6%±0.18, respectively. Rates of PTSD and partial PTSD were higher among women (8.6%±0.26 and 8.6%±0.26) than men (4.1%±0.19 and 4.5%±0.21). Respondents with both PTSD and partial PTSD most commonly reported unexpected death of someone close, serious illness or injury to someone close, and sexual assault as their worst stressful experiences. PTSD and partial PTSD were associated with elevated lifetime rates of mood, anxiety, and substance use disorders, and suicide attempts. Respondents with partial PTSD generally had intermediate odds of comorbid Axis I disorders and psychosocial impairment relative to trauma controls and full PTSD. PMID:21168991

Improved optical properties of InAs quantum dots for intermediate band solar cells by suppression of misfit strain relaxation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xie, H.; School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, Arizona 85287-6106; Prioli, R.

The properties of InAs quantum dots (QDs) have been studied for application in intermediate band solar cells. It is found that suppression of plastic relaxation in the QDs has a significant effect on the optoelectronic properties. Partial capping plus annealing is shown to be effective in controlling the height of the QDs and in suppressing plastic relaxation. A force balancing model is used to explain the relationship between plastic relaxation and QD height. A strong luminescence has been observed from strained QDs, indicating the presence of localized states in the desired energy range. No luminescence has been observed from plasticallymore » relaxed QDs.« less

Generalized intermediate long-wave hierarchy in zero-curvature representation with noncommutative spectral parameter

NASA Astrophysics Data System (ADS)

Degasperis, A.; Lebedev, D.; Olshanetsky, M.; Pakuliak, S.; Perelomov, A.; Santini, P. M.

1992-11-01

The simplest generalization of the intermediate long-wave hierarchy (ILW) is considered to show how to extend the Zakharov-Shabat dressing method to nonlocal, i.e., integro-partial differential, equations. The purpose is to give a procedure of constructing the zero-curvature representation of this class of equations. This result obtains by combining the Drinfeld-Sokolov formalism together with the introduction of an operator-valued spectral parameter, namely, a spectral parameter that does not commute with the space variable x. This extension provides a connection between the ILWk hierarchy and the Saveliev-Vershik continuum graded Lie algebras. In the case of ILW2 the Fairlie-Zachos sinh-algebra was found.

In situ Identification of Labile Precursor Compounds and their Short-lived Intermediates in Plants using in vivo Nanospray High-resolution Mass Spectrometry.

PubMed

Chang, Qing; Peng, Yue'e; Shi, Bin; Dan, Conghui; Yang, Yijun; Shuai, Qin

2016-05-01

Many secondary metabolites in plants are labile compounds which under environmental stress, are difficult to detect and track due to the lack of rapid in situ identification techniques, making plant metabolomics research difficult. Therefore, developing a reliable analytical method for rapid in situ identification of labile compounds and their short-lived intermediates in plants is of great importance. To develop under atmospheric pressure, a rapid in situ method for effective identification of labile compounds and their short-lived intermediates in fresh plants. An in vivo nanospray high-resolution mass spectrometry (HR-MS) method was used for rapid capture of labile compounds and their short-lived intermediates in plants. A quartz capillary was partially inserted into fresh plant tissues, and the liquid flowed out through the capillary tube owing to the capillary effect. A high direct current (d.c.) voltage was applied to the plant to generate a spray of charged droplets from the tip of the capillary carrying bioactive molecules toward the inlet of mass spectrometer for full-scan and MS/MS analysis. Many labile compounds and short-lived intermediates were identified via this method: including glucosinolates and their short-lived intermediates (existing for only 10 s) in Raphanus sativus roots, alliin and its conversion intermediate (existing for 20 s) in Allium sativum and labile precursor compound chlorogenic acid in Malus pumila Mill. The method is an effective approach for in situ identification of internal labile compounds and their short-lived intermediates in fresh plants and it can be used as an auxiliary tool to explore the degradation mechanisms of new labile plant compounds. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Do partial home smoking bans signal progress toward a smoke-free home?

PubMed Central

Kegler, Michelle C.; Haardörfer, Regine; Bundy, Lucja T.; Escoffery, Cam; Berg, Carla J.; Fernandez, Maria; Williams, Rebecca; Hovell, Mel

2016-01-01

Understanding who establishes partial home smoking bans, what these bans cover, and whether they are an intermediate step in going smoke-free would help to inform smoke-free home interventions. Participants were recruited from United Way of Greater Atlanta’s 2-1-1 contact center. Data were collected at baseline, 3 and 6 months via telephone interview. Participants (n = 375) were mostly African American (84.2%) and female (84.3%). The majority (58.5%) had annual household incomes <$10 000. At baseline, 61.3% reported a partial smoking ban and 38.7% reported no ban. Existence of a partial ban as compared with no ban was associated with being female, having more than a high school education, being married and younger age. Partial bans most often meant smoking was allowed only in designated rooms (52.6%). Other common rules included: no smoking in the presence of children (18.4%) and smoking allowed only in combination with actions such as opening a window or running a fan (9.8%). A higher percentage of households with partial bans at baseline were smoke-free at 6 months (36.5%) compared with households with no bans at baseline (22.1%). Households with partial smoking bans may have a higher level of readiness to go smoke-free than households with no restrictions. PMID:26661723

Evidence for a Shared Mechanism in the Formation of Urea-Induced Kinetic and Equilibrium Intermediates of Horse Apomyoglobin from Ultrarapid Mixing Experiments.

PubMed

Mizukami, Takuya; Abe, Yukiko; Maki, Kosuke

2015-01-01

In this study, the equivalence of the kinetic mechanisms of the formation of urea-induced kinetic folding intermediates and non-native equilibrium states was investigated in apomyoglobin. Despite having similar structural properties, equilibrium and kinetic intermediates accumulate under different conditions and via different mechanisms, and it remains unknown whether their formation involves shared or distinct kinetic mechanisms. To investigate the potential mechanisms of formation, the refolding and unfolding kinetics of horse apomyoglobin were measured by continuous- and stopped-flow fluorescence over a time range from approximately 100 μs to 10 s, along with equilibrium unfolding transitions, as a function of urea concentration at pH 6.0 and 8°C. The formation of a kinetic intermediate was observed over a wider range of urea concentrations (0-2.2 M) than the formation of the native state (0-1.6 M). Additionally, the kinetic intermediate remained populated as the predominant equilibrium state under conditions where the native and unfolded states were unstable (at ~0.7-2 M urea). A continuous shift from the kinetic to the equilibrium intermediate was observed as urea concentrations increased from 0 M to ~2 M, which indicates that these states share a common kinetic folding mechanism. This finding supports the conclusion that these intermediates are equivalent. Our results in turn suggest that the regions of the protein that resist denaturant perturbations form during the earlier stages of folding, which further supports the structural equivalence of transient and equilibrium intermediates. An additional folding intermediate accumulated within ~140 μs of refolding and an unfolding intermediate accumulated in <1 ms of unfolding. Finally, by using quantitative modeling, we showed that a five-state sequential scheme appropriately describes the folding mechanism of horse apomyoglobin.

Carbon Monoxide, Hydrogen, and Formate Metabolism during Methanogenesis from Acetate by Thermophilic Cultures of Methanosarcina and Methanothrix Strains.

PubMed

Zinder, S H; Anguish, T

1992-10-01

CO and H(2) have been implicated in methanogenesis from acetate, but it is unclear whether they are directly involved in methanogenesis or electron transfer in acetotrophic methanogens. We compared metabolism of H(2), CO, and formate by cultures of the thermophilic acetotrophic methanogens Methanosarcina thermophila TM-1 and Methanothrix sp. strain CALS-1. M. thermophila accumulated H(2) to partial pressures of 40 to 70 Pa (1 Pa = 0.987 x 10 atm), as has been previously reported for this and other Methanosarcina cultures. In contrast, Methanothrix sp. strain CALS-1 accumulated H(2) to maximum partial pressures near 1 Pa. Growing cultures of Methanothrix sp. strain CALS-1 initially accumulated CO, which reached partial pressures near 0.6 Pa (some CO came from the rubber stopper) during the middle of methanogenesis; this was followed by a decrease in CO partial pressures to less than 0.01 Pa by the end of methanogenesis. Accumulation or consumption of CO by cultures of M. thermophila growing on acetate was not detected. Late-exponential-phase cultures of Methanothrix sp. strain CALS-1, in which the CO partial pressure was decreased by flushing with N(2)-CO(2), accumulated CO to 0.16 Pa, whereas cultures to which ca. 0.5 Pa of CO was added consumed CO until it reached this partial pressure. Cyanide (1 mM) blocked CO consumption but not production. High partial pressures of H(2) (40 kPa) inhibited methanogenesis from acetate by M. thermophila but not by Methanothrix sp. strain CALS-1, and 2 kPa of CO was not inhibitory to M. thermophila but was inhibitory to Methanothrix sp. strain CALS-1. Levels of CO dehydrogenase, hydrogenase, and formate dehydrogenase in Methanothrix sp. strain CALS-1 were 9.1, 0.045, and 5.8 mumol of viologen reduced min mg of protein. These results suggest that CO plays a role in Methanothrix sp. strain CALS-1 similar to that of H(2) in M. thermophila and are consistent with the conclusion that CO is an intermediate in a catabolic or anabolic pathway in Methanothrix sp. strain CALS-1; however, they could also be explained by passive equilibration of CO with a metabolic intermediate.

Carbon Monoxide, Hydrogen, and Formate Metabolism during Methanogenesis from Acetate by Thermophilic Cultures of Methanosarcina and Methanothrix Strains

PubMed Central

Zinder, S. H.; Anguish, T.

1992-01-01

CO and H2 have been implicated in methanogenesis from acetate, but it is unclear whether they are directly involved in methanogenesis or electron transfer in acetotrophic methanogens. We compared metabolism of H2, CO, and formate by cultures of the thermophilic acetotrophic methanogens Methanosarcina thermophila TM-1 and Methanothrix sp. strain CALS-1. M. thermophila accumulated H2 to partial pressures of 40 to 70 Pa (1 Pa = 0.987 × 10-5 atm), as has been previously reported for this and other Methanosarcina cultures. In contrast, Methanothrix sp. strain CALS-1 accumulated H2 to maximum partial pressures near 1 Pa. Growing cultures of Methanothrix sp. strain CALS-1 initially accumulated CO, which reached partial pressures near 0.6 Pa (some CO came from the rubber stopper) during the middle of methanogenesis; this was followed by a decrease in CO partial pressures to less than 0.01 Pa by the end of methanogenesis. Accumulation or consumption of CO by cultures of M. thermophila growing on acetate was not detected. Late-exponential-phase cultures of Methanothrix sp. strain CALS-1, in which the CO partial pressure was decreased by flushing with N2-CO2, accumulated CO to 0.16 Pa, whereas cultures to which ca. 0.5 Pa of CO was added consumed CO until it reached this partial pressure. Cyanide (1 mM) blocked CO consumption but not production. High partial pressures of H2 (40 kPa) inhibited methanogenesis from acetate by M. thermophila but not by Methanothrix sp. strain CALS-1, and 2 kPa of CO was not inhibitory to M. thermophila but was inhibitory to Methanothrix sp. strain CALS-1. Levels of CO dehydrogenase, hydrogenase, and formate dehydrogenase in Methanothrix sp. strain CALS-1 were 9.1, 0.045, and 5.8 μmol of viologen reduced min-1 mg of protein-1. These results suggest that CO plays a role in Methanothrix sp. strain CALS-1 similar to that of H2 in M. thermophila and are consistent with the conclusion that CO is an intermediate in a catabolic or anabolic pathway in Methanothrix sp. strain CALS-1; however, they could also be explained by passive equilibration of CO with a metabolic intermediate. PMID:16348788

Density functional theory study of ethylene partial oxidation on Ag 7 clusters

NASA Astrophysics Data System (ADS)

Yu, Hua-Gen

2006-11-01

The partial oxidation reaction of ethylene on neutral and anionic Ag 7 clusters has been studied using the BPW91 hybrid DFT method with the Stuttgart RSC97 relativistic pseudopotential for the 28-electron ionic core of Ag. The atomic oxygen reaction mechanism is mainly addressed. Results show that the reaction occurs via a stable oxametallacycle intermediate ( AgOCH4p, p = 0 or -1), but it involves small reaction barriers along the reaction path. The ZPE-corrected barrier heights are obtained as 0.7-6.5 kcal/mole. In addition, the structure and anionic effects of Ag 7 clusters are also discussed.

Biomass hydrolysis inhibition at high hydrogen partial pressure in solid-state anaerobic digestion.

PubMed

Cazier, E A; Trably, E; Steyer, J P; Escudie, R

2015-08-01

In solid-state anaerobic digestion, so-called ss-AD, biogas production is inhibited at high total solids contents. Such inhibition is likely caused by a slow diffusion of dissolved reaction intermediates that locally accumulate. In this study, we investigated the effect of H2 and CO2 partial pressure on ss-AD. Partial pressure of H2 and/or CO2 was artificially fixed, from 0 to 1 557mbars for H2 and from 0 to 427mbars for CO2. High partial pressure of H2 showed a significant effect on methanogenesis, while CO2 had no impact. At high [Formula: see text] , the overall substrate degradation decreased with no accumulation of metabolites from acidogenic bacteria, indicating that the hydrolytic activity was specifically impacted. Interestingly, such inhibition did not occur when CO2 was added with H2. This result suggests that CO2 gas transfer is probably a key factor in ss-AD from biomass. Copyright © 2015 Elsevier Ltd. All rights reserved.

Independent saturation of three TrpRS subsites generates a partially assembled state similar to those observed in molecular simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laowanapiban, Poramaet; Kapustina, Maryna; Vonrhein, Clemens

2009-03-05

Two new crystal structures of Bacillus stearothermophilus tryptophanyl-tRNA synthetase (TrpRS) afford evidence that a closed interdomain hinge angle requires a covalent bond between AMP and an occupant of either pyrophosphate or tryptophan subsite. They also are within experimental error of a cluster of structures observed in a nonequilibrium molecular dynamics simulation showing partial active-site assembly. Further, the highest energy structure in a minimum action pathway computed by using elastic network models for Open and Pretransition state (PreTS) conformations for the fully liganded TrpRS monomer is intermediate between that simulated structure and a partially disassembled structure from a nonequilibrium molecular dynamicsmore » trajectory for the unliganded PreTS. These mutual consistencies provide unexpected validation of inferences drawn from molecular simulations.« less

Filling-enforced nonsymmorphic Kondo semimetals in two dimensions

NASA Astrophysics Data System (ADS)

Pixley, J. H.; Lee, SungBin; Brandom, B.; Parameswaran, S. A.

2017-08-01

We study the competition between Kondo screening and frustrated magnetism on the nonsymmorphic Shastry-Sutherland Kondo lattice at a filling of two conduction electrons per unit cell. This model is known to host a set of gapless partially Kondo screened phases intermediate between the Kondo-destroyed paramagnet and the heavy Fermi liquid. Based on crystal symmetries, we argue that (i) both the paramagnet and the heavy Fermi liquid are semimetals protected by a glide symmetry; and (ii) partial Kondo screening breaks the symmetry, removing this protection and allowing the partially Kondo screened phase to be deformed into a Kondo insulator via a Lifshitz transition. We confirm these results using large-N mean-field theory and then use nonperturbative arguments to derive a generalized Luttinger sum rule constraining the phase structure of two-dimensional nonsymmorphic Kondo lattices beyond the mean-field limit.

Screwless fixed detachable partial overdenture treatment for atrophic partial edentulism of the anterior maxilla.

PubMed

Flanagan, Dennis

2008-01-01

This is a case report of the restoration of a partially edentulous atrophic anterior maxilla and atrophic mandibular posterior ridges. This case report demonstrates one method for successful treatment of partial edentulism at No. 7 to 10, where interlock attachments on natural cuspids and mini dental implants support an acrylic-based screwless fixed detachable partial denture to provide lip support and masticatory function in the anterior maxilla. The presenting qualities of this case were similar to combination syndrome.

A multi-faceted tailored strategy to implement an electronic clinical decision support system for pressure ulcer prevention in nursing homes: a two-armed randomized controlled trial.

PubMed

Beeckman, Dimitri; Clays, Els; Van Hecke, Ann; Vanderwee, Katrien; Schoonhoven, Lisette; Verhaeghe, Sofie

2013-04-01

Frail older people admitted to nursing homes are at risk of a range of adverse outcomes, including pressure ulcers. Clinical decision support systems are believed to have the potential to improve care and to change the behaviour of healthcare professionals. To determine whether a multi-faceted tailored strategy to implement an electronic clinical decision support system for pressure ulcer prevention improves adherence to recommendations for pressure ulcer prevention in nursing homes. Two-armed randomized controlled trial in a nursing home setting in Belgium. The trial consisted of a 16-week implementation intervention between February and June 2010, including one baseline, four intermediate, and one post-testing measurement. Primary outcome was the adherence to guideline-based care recommendations (in terms of allocating adequate pressure ulcer prevention in residents at risk). Secondary outcomes were the change in resident outcomes (pressure ulcer prevalence) and intermediate outcomes (knowledge and attitudes of healthcare professionals). Random sample of 11 wards (6 experimental; 5 control) in a convenience sample of 4 nursing homes in Belgium. In total, 464 nursing home residents and 118 healthcare professionals participated. The experimental arm was involved in a multi-faceted tailored implementation intervention of a clinical decision support system, including interactive education, reminders, monitoring, feedback and leadership. The control arm received a hard-copy of the pressure ulcer prevention protocol, supported by standardized 30 min group lecture. Patients in the intervention arm were significantly more likely to receive fully adequate pressure ulcer prevention when seated in a chair (F=16.4, P=0.003). No significant improvement was observed on pressure ulcer prevalence and knowledge of the professionals. While baseline attitude scores were comparable between both groups [exp. 74.3% vs. contr. 74.5% (P=0.92)], the mean score after the intervention was 83.5% in the experimental group vs. 72.1% in the control group (F=15.12, P<0.001). The intervention was only partially successful to improve the primary outcome. Attitudes improved significantly while the knowledge of the healthcare workers remained unsatisfactorily low. Further research should focus on the underlying reasons for these findings. Copyright © 2012 Elsevier Ltd. All rights reserved.

Spectroscopic Observation of a Hydrogenated CO Dimer Intermediate During CO Reduction on Cu(100) Electrodes.

PubMed

Pérez-Gallent, Elena; Figueiredo, Marta C; Calle-Vallejo, Federico; Koper, Marc T M

2017-03-20

Carbon dioxide and carbon monoxide can be electrochemically reduced to useful products such as ethylene and ethanol on copper electrocatalysts. The process is yet to be optimized and the exact mechanism and the corresponding reaction intermediates are under debate or unknown. In particular, it has been hypothesized that the C-C bond formation proceeds via CO dimerization and further hydrogenation. Although computational support for this hypothesis exists, direct experimental evidence has been elusive. In this work, we detect a hydrogenated dimer intermediate (OCCOH) using Fourier transform infrared spectroscopy at low overpotentials in LiOH solutions. Density functional theory calculations support our assignment of the observed vibrational bands. The formation of this intermediate is structure sensitive, as it is observed only during CO reduction on Cu(100) and not on Cu(111), in agreement with previous experimental and computational observations. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dynamic partial reconfiguration of logic controllers implemented in FPGAs

NASA Astrophysics Data System (ADS)

Bazydło, Grzegorz; Wiśniewski, Remigiusz

2016-09-01

Technological progress in recent years benefits in digital circuits containing millions of logic gates with the capability for reprogramming and reconfiguring. On the one hand it provides the unprecedented computational power, but on the other hand the modelled systems are becoming increasingly complex, hierarchical and concurrent. Therefore, abstract modelling supported by the Computer Aided Design tools becomes a very important task. Even the higher consumption of the basic electronic components seems to be acceptable because chip manufacturing costs tend to fall over the time. The paper presents a modelling approach for logic controllers with the use of Unified Modelling Language (UML). Thanks to the Model Driven Development approach, starting with a UML state machine model, through the construction of an intermediate Hierarchical Concurrent Finite State Machine model, a collection of Verilog files is created. The system description generated in hardware description language can be synthesized and implemented in reconfigurable devices, such as FPGAs. Modular specification of the prototyped controller permits for further dynamic partial reconfiguration of the prototyped system. The idea bases on the exchanging of the functionality of the already implemented controller without stopping of the FPGA device. It means, that a part (for example a single module) of the logic controller is replaced by other version (called context), while the rest of the system is still running. The method is illustrated by a practical example by an exemplary Home Area Network system.

Can false memory for critical lures occur without conscious awareness of list words?

PubMed

Sadler, Daniel D; Sodmont, Sharon M; Keefer, Lucas A

2018-02-01

We examined whether the DRM false memory effect can occur when list words are presented below the perceptual identification threshold. In four experiments, subjects showed robust veridical memory for studied words and false memory for critical lures when masked list words were presented at exposure durations of 43 ms per word. Shortening the exposure duration to 29 ms virtually eliminated veridical recognition of studied words and completely eliminated false recognition of critical lures. Subjective visibility ratings in Experiments 3a and 3b support the assumption that words presented at 29 ms were subliminal for most participants, but were occasionally experienced with partial awareness by participants with higher perceptual awareness. Our results indicate that a false memory effect does not occur in the absence of conscious awareness of list words, but it does occur when word stimuli are presented at an intermediate level of visibility. Copyright © 2017 Elsevier Inc. All rights reserved.

Numerical simulation of exploding pusher targets

NASA Astrophysics Data System (ADS)

Atzeni, S.; Rosenberg, M. J.; Gatu Johnson, M.; Petrasso, R. D.

2017-10-01

Exploding pusher targets, i.e. gas-filled large aspect-ratio glass or plastic shells, driven by a strong laser-generated shock, are widely used as pulsed sources of neutrons and fast charged particles. Recent experiments on exploding pushers provided evidence for the transition from a purely fluid behavior to a kinetic one. Indeed, fluid models largely overpredict yield and temperature as the Knudsen number Kn (ratio of ion mean-free path to compressed gas radius) is comparable or larger than one. At Kn = 0.3 - 1, fluid codes reasonably estimate integral quantities as yield and neutron-averaged temperatures, but do not reproduce burn radii, burn profiles and DD/DHe3 yield ratio. This motivated a detailed simulation study of intermediate-Kn exploding pushers. We will show how simulation results depend on models for laser-interaction, electron conductivity (flux-limited local vs nonlocal), viscosity (physical vs artificial), and ion mixing. Work partially supported by Sapienza Project C26A15YTMA, Sapienza 2016 (n. 257584), and Eurofusion Project AWP17-ENR-IFE-CEA-01.

Mycobacterium minnesotense sp. nov., a photochromogenic bacterium isolated from sphagnum peat bogs.

PubMed

Hannigan, Geoffrey D; Krivogorsky, Bogdana; Fordice, Daniel; Welch, Jacqueline B; Dahl, John L

2013-01-01

Several intermediate-growing, photochromogenic bacteria were isolated from sphagnum peat bogs in northern Minnesota, USA. Acid-fast staining and 16S rRNA gene sequence analysis placed these environmental isolates in the genus Mycobacterium, and colony morphologies and PCR restriction analysis patterns of the isolates were similar. Partial sequences of hsp65 and dnaJ1 from these isolates showed that Mycobacterium arupense ATCC BAA-1242(T) was the closest mycobacterial relative, and common biochemical characteristics and antibiotic susceptibilities existed between the isolates and M. arupense ATCC BAA-1242(T). However, compared to nonchromogenic M. arupense ATCC BAA-1242(T), the environmental isolates were photochromogenic, had a different mycolic acid profile and had reduced cell-surface hydrophobicity in liquid culture. The data reported here support the conclusion that the isolates are representatives of a novel mycobacterial species, for which the name Mycobacterium minnesotense sp. nov. is proposed. The type strain is DL49(T) (=DSM 45633(T) = JCM 17932(T) = NCCB 100399(T)).

Charge-Triggered Membrane Insertion of Matrix Metalloproteinase-7, Supporter of Innate Immunity and Tumors.

PubMed

Prior, Stephen H; Fulcher, Yan G; Koppisetti, Rama K; Jurkevich, Alexander; Van Doren, Steven R

2015-11-03

Matrix metalloproteinase-7 (MMP-7) sheds signaling proteins from cell surfaces to activate bacterial killing, wound healing, and tumorigenesis. The mechanism targeting soluble MMP-7 to membranes has been investigated. Nuclear magnetic resonance structures of the zymogen, free and bound to membrane mimics without and with anionic lipid, reveal peripheral binding to bilayers through paramagnetic relaxation enhancements. Addition of cholesterol sulfate partially embeds the protease in the bilayer, restricts its diffusion, and tips the active site away from the bilayer. Its insertion of hydrophobic residues organizes the lipids, pushing the head groups and sterol sulfate outward toward the enzyme's positive charge on the periphery of the enlarged interface. Fluorescence probing demonstrates a similar mode of binding to plasma membranes and internalized vesicles of colon cancer cells. Binding of bilayered micelles induces allosteric activation and conformational change in the auto-inhibitory peptide and the adjacent scissile site, illustrating a potential intermediate in the activation of the zymogen. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mechanistic understanding of monosaccharide-air flow battery electrochemistry

NASA Astrophysics Data System (ADS)

Scott, Daniel M.; Tsang, Tsz Ho; Chetty, Leticia; Aloi, Sekotilani; Liaw, Bor Yann

Recently, an inexpensive monosaccharide-air flow battery configuration has been demonstrated to utilize a strong base and a mediator redox dye to harness electrical power from the partial oxidation of glucose. Here the mechanistic understanding of glucose oxidation in this unique glucose-air power source is further explored by acid-base titration experiments, 13C NMR, and comparison of results from chemically different redox mediators (indigo carmine vs. methyl viologen) and sugars (fructose vs. glucose) via studies using electrochemical techniques. Titration results indicate that gluconic acid is the main product of the cell reaction, as supported by evidence in the 13C NMR spectra. Using indigo carmine as the mediator dye and fructose as the energy source, an abiotic cell configuration generates a power density of 1.66 mW cm -2, which is greater than that produced from glucose under similar conditions (ca. 1.28 mW cm -2). A faster transition from fructose into the ene-diol intermediate than from glucose likely contributed to this difference in power density.

Free Radicals and Reactive Intermediates for the SAGE III Ozone Loss and Validation Experiment (SOLVE) Mission

NASA Technical Reports Server (NTRS)

Anderson, James G.

2001-01-01

This grant provided partial support for participation in the SAGE III Ozone Loss and Validation Experiment. The NASA-sponsored SOLVE mission was conducted Jointly with the European Commission-sponsored Third European Stratospheric Experiment on Ozone (THESEO 2000). Researchers examined processes that control ozone amounts at mid to high latitudes during the arctic winter and acquired correlative data needed to validate the Stratospheric Aerosol and Gas Experiment (SAGE) III satellite measurements that are used to quantitatively assess high-latitude ozone loss. The campaign began in September 1999 with intercomparison flights out of NASA Dryden Flight Research Center in Edwards. CA. and continued through March 2000. with midwinter deployments out of Kiruna. Sweden. SOLVE was co-sponsored by the Upper Atmosphere Research Program (UARP). Atmospheric Effects of Aviation Project (AEAP). Atmospheric Chemistry Modeling and Analysis Program (ACMAP). and Earth Observing System (EOS) of NASA's Earth Science Enterprise (ESE) as part of the validation program for the SAGE III instrument.

Conceptual design of a data reduction system

NASA Technical Reports Server (NTRS)

1983-01-01

A telemetry data processing system was defined of the Data Reduction. Data reduction activities in support of the developmental flights of the Space Shuttle were used as references against which requirements are assessed in general terms. A conceptual system design believed to offer significant throughput for the anticipated types of data reduction activities is presented. The design identifies the use of a large, intermediate data store as a key element in a complex of high speed, single purpose processors, each of which performs predesignated, repetitive operations on either raw or partially processed data. The recommended approach to implement the design concept is to adopt an established interface standard and rely heavily on mature or promising technologies which are considered main stream of the integrated circuit industry. The design system concept, is believed to be implementable without reliance on exotic devices and/or operational procedures. Numerical methods were employed to examine the feasibility of digital discrimination of FDM composite signals, and of eliminating line frequency noises in data measurements.

Aggregation and Stability of Reduced Graphene Oxide: Complex Roles of Divalent Cations, pH, and Natural Organic Matter

EPA Science Inventory

The aggregation and stability of graphene oxide (GO) and three successively reduced GO (rGO) nanomaterials were investigated. Reduced GO species were partially reduced GO (rGO-1h), intermediately reduced GO (rGO-2h), and fully reduced GO (rGO-5h). Specifically, influence of pH, i...

The impacts of NAFTA on U.S. and Canadian forest product exports to Mexico

Treesearch

Jeffrey P. Prestemon; Joseph Buongiorno

1996-01-01

The North American Free Trade Agreement (NAFTA) will lower barriers to trade and investment across the continent. This paper presents predictions of the effects of NAFTA on Mexico's imports of intermediate wood products, scrap and waste paper, pulp, and newsprint from the United States and Canada. Predictions were made with a partial equilibrium model. Model...

Importance of succession, harvest, and climate change in determining future composition in US Central Hardwood Forests

Treesearch

Wen J. Wang; Hong S. He; Frank R. Thompson; Jacob S. Fraser; Brice B. Hanberry; William D. Dijak

2015-01-01

Most temperate forests in U.S. are recovering from heavy exploitation and are in intermediate successional stages where partial tree harvest is the primary disturbance. Changes in regional forest composition in response to climate change are often predicted for plant functional types using biophysical process models. These models usually simplify the simulation of...

Growth and yield of western larch under controlled levels of stocking in the Blue Mountains of Oregon.

Treesearch

P.H. Cochran; K.W. Seidel

1999-01-01

Repeated thinning to five growing-stock levels resulted in widely differing tree sizes and volumes per acre after 30 years. Largest trees but the least cubic-volume yield per acre were produced in the heaviest thinning level, whereas highest board-foot yields were found in intermediate thinning levels. Partial defoliation by larch casebearer (Coleophora...

The Spin Pulse of the Intermediate Polar V1062 Tauri

NASA Technical Reports Server (NTRS)

Hellier, Coel; Beardmore, A. P.; Mukai, Koji; White, Nicholas E. (Technical Monitor)

2002-01-01

We combine ASCA and RXTE data of V1062 Tau to confirm the presence of a 62-min X-ray pulsation. We show that the pulsation is caused largely by the variation of dense partial absorption, in keeping with current models of accretion onto magnetic white dwarfs. Further parameterisation of the spin pulse is, however, hampered by ambiguities in the models.

Partial dehydration and cryopreservation of Citrus seeds.

PubMed

Graiver, Natalia; Califano, Alicia; Zaritzky, Noemí

2011-11-01

Three categories of seed storage behavior are generally recognized among plant species: orthodox, intermediate and recalcitrant. Intermediate seeds cannot be stored in liquid nitrogen (LN) without a previous partial dehydration process. The water content (WC) of the seeds at the moment of immersion in LN must be regarded as the most critical factor in cryopreservation. The purpose of this study was to investigate the basis of the optimal hydration status for cryopreservation of Citrus seeds: C. sinensis (sweet orange), C. paradisi (grapefruit), C. reticulata (mandarin) in LN. To study the tolerance to dehydration and LN exposure, seeds were desiccated by equilibration at relative humidities between 11 and 95%. Sorption isotherms were determined and modeled; lipid content of the seeds was measured. Seed desiccation sensitivity was quantified by the quantal response model. Differential scanning calorimetry (DSC) thermograms were determined on cotyledon tissue at different moisture contents to measure ice melting enthalpies and unfrozen WC. Samples of total seed lipid extract were also analyzed by DSC to identify lipid transitions in the thermograms. The limit of hydration for LN Citrus seeds treatment corresponded to the unfrozen WC in the tissue, confirming that seed survival strictly depended on avoidance of intracellular ice formation. Copyright © 2011 Society of Chemical Industry.

Transitional Disks Associated with Intermediate-Mass Stars: Results of the SEEDS YSO Survey

NASA Technical Reports Server (NTRS)

Grady, C.; Fukagawa, M.; Maruta, Y.; Ohta, Y.; Wisniewski, J.; Hashimoto, J.; Okamoto, Y.; Momose, M.; Currie, T.; McElwain, M.;

Mechanisms of protein misfolding: Novel therapeutic approaches to protein-misfolding diseases

NASA Astrophysics Data System (ADS)

Salahuddin, Parveen; Siddiqi, Mohammad Khursheed; Khan, Sanaullah; Abdelhameed, Ali Saber; Khan, Rizwan Hasan

2016-11-01

In protein misfolding, protein molecule acquires wrong tertiary structure, thereby induces protein misfolding diseases. Protein misfolding can occur through various mechanisms. For instance, changes in environmental conditions, oxidative stress, dominant negative mutations, error in post-translational modifications, increase in degradation rate and trafficking error. All of these factors cause protein misfolding thereby leading to diseases conditions. Both in vitro and in vivo observations suggest that partially unfolded or misfolded intermediates are particularly prone to aggregation. These partially misfolded intermediates aggregate via the interaction with the complementary intermediates and consequently enhance oligomers formation that grows into fibrils and proto-fibrils. The amyloid fibrils for example, accumulate in the brain and central nervous system (CNS) as amyloid deposits in the Parkinson's disease (PD), Alzheimer's disease (AD), Prion disease and Amylo lateral Sclerosis (ALS). Furthermore, tau protein shows intrinsically disorder conformation; therefore its interaction with microtubule is impaired and this protein undergoes aggregation. This is also underlying cause of Alzheimers and other neurodegenerative diseases. Treatment of such misfolding maladies is considered as one of the most important challenges of the 21st century. Currently, several treatments strategies have been and are being discovered. These therapeutic interventions partly reversed or prevented the pathological state. More recently, a new approach was discovered, which employs nanobodies that targets multisteps in fibril formation pathway that may possibly completely cure these misfolding diseases. Keeping the above views in mind in the current review, we have comprehensively discussed the different mechanisms underlying protein misfolding thereby leading to diseases conditions and their therapeutic interventions.

Upper Tract Urological Laparoendoscopic Single-Site Surgery (LESS)

PubMed Central

Tugcu, Volkan; Sahin, Selcuk; Seker, Gokhan; Kargi, Taner; Tasci, Ali Ihsan

2015-01-01

Background and Objectives: Our objective is to report intermediate-term outcomes for patients who have undergone upper tract urologic laparoendoscopic single-site surgery (LESS) at a single institution. Methods: From January 1, 2008, through November 30, 2012, 107 cases treated with LESS were identified, including pyeloplasty (n = 30), ureterolithotomy (n = 32), nephrectomy (n = 35; simple = 31, partial = 4), and cyst decortication (n = 10). Perioperative data were reviewed, and conversion and complication rates were noted. Results: The median follow-up was 21.5 months for pyeloplasty, 20.5 for ureterolithotomy, 28.0 for simple nephrectomy, 14.0 for partial nephrectomy, and 19.0 for cyst decortication. Major complications were encountered in 8 patients, including 3 intraoperative complications (2 bowel injury with serosal tearing and 1 intraoperative bleeding), which were recognized and repaired with LESS or conversion to conventional laparoscopy (CL). During the intermediate postoperative period (30–90 days) major complications occurred in 5 patients: 4 ureteral strictures (Clavien-Dindo grade [CG] IIIb) and 1 urinoma formation (CG IIIa). During the early postoperative period (<30 days), the most common minor complications were flank pain (CG I) in 16 patients and urinary tract infection (CG II) in 11, followed by urinary leakage (CG I) in 8. Conclusions: Intermediate-term functional outcomes of this single-center study confirm that upper tract LESS is a challenging procedure that can be safe and effective when performed by an experienced team. Prospective studies with longer follow-up periods are needed to investigate the safety of LESS in the treatment of various upper urinary tract conditions. PMID:26648679

Active Surveillance for Low and Intermediate Risk Prostate Cancer: Opinions of North American Genitourinary Oncology Expert Radiation Oncologists.

PubMed

McClelland, Shearwood; Sandler, Kiri A; Degnin, Catherine; Chen, Yiyi; Mitin, Timur

2018-04-01

The ProtecT trial has provided level 1 evidence supporting active surveillance for prostate cancer patients with low-risk and intermediate-risk disease. The effect of these findings on the opinions of North American genitourinary (GU) experts regarding the role of active surveillance for these patients has not been previously examined. A survey was distributed to 88 practicing North American GU physicians serving on decision-making committees of cooperative group research organizations. Questions pertained to appropriateness of active surveillance in patients with low-risk and intermediate-risk (Gleason 3+4) disease. Opinions regarding active surveillance were correlated with practice patterns using Fisher exact test. Forty-two radiation oncologists completed the survey. Forty percent had been in practice for more than 20 years; 90% practice at an academic center. Forty-five percent see ≥ 20 patients per month in consultation. More than 95% (40 of 42) recommended active surveillance for Gleason 6 disease, whereas only 17% recommended active surveillance for Gleason 3+4 disease. There were no demographic differences between supporters or opponents regarding active surveillance with regard to monthly patient volume, practice type, likelihood of self-identifying as an expert brachytherapist, belief in advanced imaging techniques, or preferred default external beam radiation therapy dose/fractionation for either low-risk or intermediate-risk disease. However, there was a trend toward greater support of active surveillance for Gleason 3+4 disease among experts having practiced < 10 years versus ≥ 10 years (P = .085). Active surveillance is almost universally supported by North American GU expert radiation oncologists for low-risk prostate cancer. However, there is very weak support for this strategy in Gleason 3+4 disease despite the ProtecT trial providing level 1 evidentiary support in both risk groups. There were no significant differences between experts supporting versus opposing active surveillance for either low-risk or intermediate-risk disease. These preferences might affect the design of future clinical studies, influencing the adoption of active surveillance in North American clinical practice. Copyright © 2017 Elsevier Inc. All rights reserved.

Elements of progressive patient care in the Yale Health Plan HMO.

PubMed

Pearson, D A; Rowe, D S; Goldberg, B; Seigel, E

1975-01-01

The results of a study of the use of intermediate care beds in the intermediate care facility (ICF) of the Yale Health Plan, a prepaid group practice plan for students and an enrolled non-student population, indicate that the ICF may be a possible model for other health maintenance organizations. The ICF, with 30 beds in active use, is located in the Yale health center. Approximately one-third of the ICF patients would have been admitted to the affiliated short-term general hospital if the ICF did not exist. The plan's medical staff also has the option of transferring patients between the affiliated hospital and the ICF, depending on which institution is most appropriate for the patient's needs. A comparison of the levels of care provided in the ICF with those presented in selected articles from the progressive patient care literature revealed that the ICF is not only providing intermediate care but several other classic elements of progressive patient care -self care, continuing care, minimal care, and partial care.

Elements of progressive patient care in the Yale Health Plan HMO.

PubMed Central

Pearson, D A; Rowe, D S; Goldberg, B; Seigel, E

1975-01-01

The results of a study of the use of intermediate care beds in the intermediate care facility (ICF) of the Yale Health Plan, a prepaid group practice plan for students and an enrolled non-student population, indicate that the ICF may be a possible model for other health maintenance organizations. The ICF, with 30 beds in active use, is located in the Yale health center. Approximately one-third of the ICF patients would have been admitted to the affiliated short-term general hospital if the ICF did not exist. The plan's medical staff also has the option of transferring patients between the affiliated hospital and the ICF, depending on which institution is most appropriate for the patient's needs. A comparison of the levels of care provided in the ICF with those presented in selected articles from the progressive patient care literature revealed that the ICF is not only providing intermediate care but several other classic elements of progressive patient care -self care, continuing care, minimal care, and partial care. PMID:805444

ATP-induced noncooperative thermal unfolding of hen lysozyme

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Honglin; Yin, Peidong; He, Shengnan

To understand the role of ATP underlying the enhanced amyloidosis of hen egg white lysozyme (HEWL), the synchrotron radiation circular dichroism, combined with tryptophan fluorescence, dynamic light-scattering, and differential scanning calorimetry, is used to examine the alterations of the conformation and thermal unfolding pathway of the HEWL in the presence of ATP, Mg{sup 2+}-ATP, ADP, AMP, etc. It is revealed that the binding of ATP to HEWL through strong electrostatic interaction changes the secondary structures of HEWL and makes the exposed residue W62 move into hydrophobic environments. This alteration of W62 decreases the {beta}-domain stability of HEWL, induces a noncooperativemore » unfolding of the secondary structures, and produces a partially unfolded intermediate. This intermediate containing relatively rich {alpha}-helix and less {beta}-sheet structures has a great tendency to aggregate. The results imply that the ease of aggregating of HEWL is related to the extent of denaturation of the amyloidogenic region, rather than the electrostatic neutralizing effect or monomeric {beta}-sheet enriched intermediate.« less

4. VAL PARTIAL ELEVATION SHOWING LAUNCHER BRIDGE ON SUPPORTS, LAUNCHER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. VAL PARTIAL ELEVATION SHOWING LAUNCHER BRIDGE ON SUPPORTS, LAUNCHER SLAB, SUPPORT CARRIAGE, CONCRETE 'A' FRAME STRUCTURE AND CAMERA TOWER LOOKING SOUTHEAST. - Variable Angle Launcher Complex, Variable Angle Launcher, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

The structure of molten CuCl: Reverse Monte Carlo modeling with high-energy X-ray diffraction data and molecular dynamics of a polarizable ion model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alcaraz, Olga; Trullàs, Joaquim, E-mail: quim.trullas@upc.edu; Tahara, Shuta

2016-09-07

The results of the structural properties of molten copper chloride are reported from high-energy X-ray diffraction measurements, reverse Monte Carlo modeling method, and molecular dynamics simulations using a polarizable ion model. The simulated X-ray structure factor reproduces all trends observed experimentally, in particular the shoulder at around 1 Å{sup −1} related to intermediate range ordering, as well as the partial copper-copper correlations from the reverse Monte Carlo modeling, which cannot be reproduced by using a simple rigid ion model. It is shown that the shoulder comes from intermediate range copper-copper correlations caused by the polarized chlorides.

Benzene oxidation at diamond electrodes: comparison of microcrystalline and nanocrystalline diamonds.

PubMed

Pleskov, Yu V; Krotova, M D; Elkin, V V; Varnin, V P; Teremetskaya, I G; Saveliev, A V; Ralchenko, V G

2012-08-27

A comparative study of benzene oxidation at boron-doped diamond (BDD) and nitrogenated nanocrystalline diamond (NCD) anodes in 0.5 M K(2)SO(4) aqueous solution is conducted by using cyclic voltammetry and electrochemical impedance spectroscopy. It is shown by measurements of differential capacitance and anodic current that during the benzene oxidation at the BDD electrode, adsorption of a reaction intermediate occurs, which partially blocks the electrode surface and lowers the anodic current. At the NCD electrode, benzene is oxidized concurrently with oxygen evolution, a (quinoid) intermediate being adsorbed at the electrode. The adsorption and the electrode surface blocking are reflected in the impedance-frequency and impedance-potential complex-plane plots. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fluorination of 1,2,3-, 1,2,4-, and 1,3,5-trihalobenzenes with potassium fluoride in dimethyl sulfone

USGS Publications Warehouse

Shiley, R.H.; Dickerson, D.R.; Finger, G.C.

1972-01-01

Three trifluorobenzenes were prepared by reaction of the corresponding trichlorobenzenes with potassium fluoride or pottassium fluoride-cesium fluoride mixtures in dimethyl sulfone. Molar yields were 12.8% for 1,2,3-, 8.3% for 1,2,4-, and 56.2% for 1,3,5-. Improved yields of the 1,2,3- (23.9%) and the 1,2,4- (34.0%) trifluorobenzenes were obtained from certain partially fluorinated intermediates. Several chlorofluorobenzene intermediates were obtained in goods yields by careful control of the reaction variables. The instability of the polyfluorobenzenes in the halogen-exchange reaction medium explains, in part, why only limited yields of the polyfluorobenzenes are obtained by using this method. ?? 1972.

Isolation of three hexahydro-1,3,5-trinitro-1,3,5-triazine-degrading species of the family Enterobacteriaceae from nitramine explosive-contaminated soil.

PubMed Central

Kitts, C L; Cunningham, D P; Unkefer, P J

1994-01-01

Three species of the family Enterobacteriaceae that biochemically reduced hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) were isolated from nitramine explosive-contaminated soil. Two isolates, identified as Morganella morganii and Providencia rettgeri, completely transformed both RDX and the nitroso-RDX reduction intermediates. The third isolate, identified as Citrobacter freundii, partially transformed RDX and generated high concentrations of nitroso-RDX intermediates. All three isolates produced 14CO2 from labeled RDX under O2-depleted culture conditions. While all three isolates transformed HMX, only M. morganii transformed HMX in the presence of RDX. PMID:7811097

The association of 83 plasma proteins with CHD mortality, BMI, HDL-, and total-cholesterol in men: applying multivariate statistics to identify proteins with prognostic value and biological relevance.

PubMed

Heidema, A Geert; Thissen, Uwe; Boer, Jolanda M A; Bouwman, Freek G; Feskens, Edith J M; Mariman, Edwin C M

2009-06-01

In this study, we applied the multivariate statistical tool Partial Least Squares (PLS) to analyze the relative importance of 83 plasma proteins in relation to coronary heart disease (CHD) mortality and the intermediate end points body mass index, HDL-cholesterol and total cholesterol. From a Dutch monitoring project for cardiovascular disease risk factors, men who died of CHD between initial participation (1987-1991) and end of follow-up (January 1, 2000) (N = 44) and matched controls (N = 44) were selected. Baseline plasma concentrations of proteins were measured by a multiplex immunoassay. With the use of PLS, we identified 15 proteins with prognostic value for CHD mortality and sets of proteins associated with the intermediate end points. Subsequently, sets of proteins and intermediate end points were analyzed together by Principal Components Analysis, indicating that proteins involved in inflammation explained most of the variance, followed by proteins involved in metabolism and proteins associated with total-C. This study is one of the first in which the association of a large number of plasma proteins with CHD mortality and intermediate end points is investigated by applying multivariate statistics, providing insight in the relationships among proteins, intermediate end points and CHD mortality, and a set of proteins with prognostic value.

Formal support for informal caregivers to older persons with dementia through the course of the disease: an exploratory, cross-sectional study.

PubMed

Lethin, Connie; Leino-Kilpi, Helena; Roe, Brenda; Soto, Maria Martin; Saks, Kai; Stephan, Astrid; Zwakhalen, Sandra; Zabalegui, Adelaida; Karlsson, Staffan

2016-01-29

In European countries, knowledge about availability and utilization of support for informal caregivers caring for older persons (≥65 years) with dementia (PwD) is lacking. To be able to evaluate and develop the dementia support system for informal caregivers to PwD, a survey of European support systems and professionals involved is needed. The aim of this study was to explore support for informal caregivers to PwD in European countries. We investigated the availability and utilization of support in each of the participating countries, and the professional care providers involved, through the dementia disease. A mapping system was used in 2010-2011 to gather information about estimations of availability, utilization, and professional providers of support to informal caregivers caring for PwD. Data collected was representing each country as a whole. There was high availability of counselling, caregiver support, and education from the diagnosis to the intermediate stage, with a decrease in the late to end of life stage. Utilization was low, although there was a small increase in the intermediate stage. Day care and respite care were highly available in the diagnosis to the intermediate stage, with a decrease in the late to end of life stage, but both types of care were utilized by few or no caregivers through any of the disease stages. Professionals specialized in dementia (Bachelor to Master's degree) provided counselling and education, whereas caregiver support for informal caregivers and day care, respite care, and respite care at home were provided by professionals with education ranging from upper secondary schooling to a Master's degree. Counselling, caregiver support, and education were highly available in European countries from diagnosis to the intermediate stage of the dementia disease, decreasing in the late/end of life stages but were rarely utilized. Countries with care systems based on national guidelines for dementia care seem to be more aware of the importance of professionals specialized in dementia care when providing support to informal caregivers. Mapping the systems of support for informal caregivers of PwD is a valuable tool for evaluating existing systems, internationally, nationally and locally for policy making.

Methanol partial oxidation on Ag(111) from first principles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aljama, Hassan; Yoo, Jong Suk; Nørskov, Jens K.

In this work, we examine the thermochemistry and kinetics of the partial oxidation of methanol to formaldehyde on silver surfaces. Periodic density functional theory calculations employing the BEEF-vdW functional are used to identify the most stable phases of the silver surface under relevant reaction conditions and the reaction energetics are obtained on these surfaces. The calculated binding energies and transition state energies are used as input in a mean-field microkinetic model providing the reaction kinetics on silver surfaces under different reaction conditions. Our results show that, under conditions pertaining to methanol partial oxidation, oxygen is present at low concentrations andmore » it plays a critical role in the catalytic reaction. Surface oxygen promotes the reaction by activating the OH bond in methanol, thus forming a methoxy intermediate, which can react further to form formaldehyde. Finally, the dissociation of molecular oxygen is identified as the most critical step.« less

Methanol partial oxidation on Ag(111) from first principles

DOE PAGES

Aljama, Hassan; Yoo, Jong Suk; Nørskov, Jens K.; ...

2016-10-26

In this work, we examine the thermochemistry and kinetics of the partial oxidation of methanol to formaldehyde on silver surfaces. Periodic density functional theory calculations employing the BEEF-vdW functional are used to identify the most stable phases of the silver surface under relevant reaction conditions and the reaction energetics are obtained on these surfaces. The calculated binding energies and transition state energies are used as input in a mean-field microkinetic model providing the reaction kinetics on silver surfaces under different reaction conditions. Our results show that, under conditions pertaining to methanol partial oxidation, oxygen is present at low concentrations andmore » it plays a critical role in the catalytic reaction. Surface oxygen promotes the reaction by activating the OH bond in methanol, thus forming a methoxy intermediate, which can react further to form formaldehyde. Finally, the dissociation of molecular oxygen is identified as the most critical step.« less

Building polyhedra by self-assembly: theory and experiment.

PubMed

Kaplan, Ryan; Klobušický, Joseph; Pandey, Shivendra; Gracias, David H; Menon, Govind

2014-01-01

We investigate the utility of a mathematical framework based on discrete geometry to model biological and synthetic self-assembly. Our primary biological example is the self-assembly of icosahedral viruses; our synthetic example is surface-tension-driven self-folding polyhedra. In both instances, the process of self-assembly is modeled by decomposing the polyhedron into a set of partially formed intermediate states. The set of all intermediates is called the configuration space, pathways of assembly are modeled as paths in the configuration space, and the kinetics and yield of assembly are modeled by rate equations, Markov chains, or cost functions on the configuration space. We review an interesting interplay between biological function and mathematical structure in viruses in light of this framework. We discuss in particular: (i) tiling theory as a coarse-grained description of all-atom models; (ii) the building game-a growth model for the formation of polyhedra; and (iii) the application of these models to the self-assembly of the bacteriophage MS2. We then use a similar framework to model self-folding polyhedra. We use a discrete folding algorithm to compute a configuration space that idealizes surface-tension-driven self-folding and analyze pathways of assembly and dominant intermediates. These computations are then compared with experimental observations of a self-folding dodecahedron with side 300 μm. In both models, despite a combinatorial explosion in the size of the configuration space, a few pathways and intermediates dominate self-assembly. For self-folding polyhedra, the dominant intermediates have fewer degrees of freedom than comparable intermediates, and are thus more rigid. The concentration of assembly pathways on a few intermediates with distinguished geometric properties is biologically and physically important, and suggests deeper mathematical structure.

77 FR 14022 - Guidance for Industry on Chemistry, Manufacturing, and Controls Information-Fermentation-Derived...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-08

...] Guidance for Industry on Chemistry, Manufacturing, and Controls Information--Fermentation-Derived... (CMC) Information-- Fermentation-Derived Intermediates, Drug Substances, and Related Drug Products for... to submit to support the CMC information for fermentation-derived intermediates, drug substances, and...

Investigation of the Origin of Catalytic Activity in Oxide-Supported Nanoparticle Gold

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harrison, Ian

Since Haruta’s discovery in 1987 of the surprising catalytic activity of supported Au nanoparticles, we have seen a very large number of experimental and theoretical efforts to explain this activity and to fully understand the nature of the behavior of the responsible active sites. In 2011, we discovered that a dual catalytic site at the perimeter of ~3nm diameter Au particles supported on TiO 2 is responsible for oxidative catalytic activity. O 2 molecules bind with Au atoms and Ti4+ ions in the TiO 2 support and the weakened O-O bond dissociates at low temperatures, proceeding to produce O atomsmore » which act as oxidizing agents for the test molecule, CO. The papers supported by DOE have built on this finding and have been concerned with two aspects of the behavior of Au/TiO 2 catalysts: (1). Mechanistic behavior of dual catalytic sites in the oxidation of organic molecules such as ethylene and acetic acid; (2). Studies of the electronic properties of the TiO 2 (110) single crystal in relation to its participation in charge transfer at the occupied dual catalytic site. A total of 20 papers have been produced through DOE support of this work. The papers combine IR spectroscopic investigations of Au/TiO 2 catalysts with surface science on the TiO 2(110) and TiO 2 nanoparticle surfaces with modern density functional modeling. The primary goals of the work were to investigate the behavior of the dual Au/Ti 4+ site for the partial oxidation of alcohols to acids, the hydrogenation of aldehydes and ketones to alcohols, and the condensation of oxygenate intermediates- all processes related to the utilization of biomass in the production of useful chemical energy sources.« less

The physical chemistry of Criegee intermediates in the gas phase

DOE PAGES

Osborn, David L.; Taatjes, Craig A.

2015-07-24

Here, carbonyl oxides, also known as Criegee intermediates, are key intermediates in both gas phase ozonolysis of unsaturated hydrocarbons in the troposphere and solution phase organic synthesis via ozonolysis. Although the study of Criegee intermediates in both arenas has a long history, direct studies in the gas phase have only recently become possible through new methods of generating stabilised Criegee intermediates in sufficient quantities. This advance has catalysed a large number of new experimental and theoretical investigations of Criegee intermediate chemistry. In this article we review the physical chemistry of Criegee intermediates, focusing on their molecular structure, spectroscopy, unimolecular andmore » bimolecular reactions. These recent results have overturned conclusions from some previous studies, while confirming others, and have clarified areas of investigation that will be critical targets for future studies. In addition to expanding our fundamental understanding of Criegee intermediates, the rapidly expanding knowledge base will support increasingly predictive models of their impacts on society.« less

[Biomedical research, the market, clinicians, safety and corporate social responsibility post-phase III: maintaining confidence].

PubMed

Marín-Gámez, N; Kessel-Sardiñas, H; Cervantes-Bonet, B; López-Palmero, S; Antón-Molina, F; Martínez-García, L

2010-01-01

Randomised controlled trials (RCTs) are the gold standard in the western world for decision making, as much for the clinicians as for the agencies or managers for community policies. In this powerful deployment of investigative effort there are variable degrees of conflict of interests, and the clinicians, not foreign to this, are entering a sea of doubts on safety, a dimension that emerges like a diacritical, inalienable element. The aim of the study was to select and ctically evaluate editorials, clinical trials and/or meta-analyses published on physical support, or the more important internationally credited websites, which has patient safety as their primary objective. Evaluative study performed in the Torrecardenas Hospital, of the Andalucian Public Health Service (SSPA), in the context of an accredited training unit (Mejora_F), so called "transference of the biomedical knowledge from the bibliography" from 2008 to 2009. Analyzed articles: 170 (75 % in English, with predominance of N Eng J Med >50 %; followed by Journal Of the American Medical Association, The Lancet, British Medical Journal, Journal of American Geriatrics; Med Clin, Rev Clin Esp.; and Infectología). From 170 eligible articles we selected 5 key topoi due to their impact as the most representative owing to their citation frequency. They represented, in our judgment, "a red flag" of safety: long-acting beta-stimulators or LABS and increase in mortality in asthma; neuroleptics in the elderly and extension of the QT interval associated with sudden death; thiazolidinediones in type II diabetes and negative cardiovascular effects; promotion of statins-ezetimibe and the debatable association with major mortality for cancer, and intensive treatment in diabetes and probable increase in mortality. What really maters in biomedicine is that it leads to a given strategy in real patients, not the intermediate points. Clinicians should not support partial results of designs based on intermediate information - undoubtedly less costly and more rapid - without adequately knowing the safety of the strategy built to reach them. Only in this way we can be real guarantors of safety, and only in this way, and in absence of conflicts of interests we will be able to support the given confidence.

Endemic angiostrongyliasis in the Brazilian Amazon: natural parasitism of Angiostrongylus cantonensis in Rattus rattus and R. norvegicus, and sympatric giant African land snails, Achatina fulica.

PubMed

Moreira, V L C; Giese, E G; Melo, F T V; Simões, R O; Thiengo, S C; Maldonado, A; Santos, J N

2013-01-01

Angiostrongylus cantonensis, the rat lungworm, is one etiological agent of eosinophilic meningoencephalitis in humans. This zoonosis is frequently found in Asia and, more recently, in North America, Caribbean Island and northeastern of South America. Until now, research of A. cantonensis in southern, southeastern and northeastern regions of Brazil has been found natural infections only terrestrial and freshwater intermediate snail hosts (Achatina fulica, Sarasinula marginata, Subulina octona, Bradybaena similaris and Pomacea lineate). In this study, we examined the occurrence of helminthes in the synantropic rodents Rattus rattus and Rattus norvegicus in northern Brazil, focusing on the role of these species as vertebrate hosts of A. cantonensis and A. fulica as intermediate host have found natural. Thirty specimens of R. rattus and twelve of R. norvegicus were collected in the Guamá and Jurunas neighborhoods of the city of Belém, in the Brazilian state of Pará, of which almost 10% harbored adult worms in their pulmonary arteries. Sympatric A. fulica were found to be infected by L(3) larvae, which experimental infection confirmed to be A. cantonensis. Natural infection of snails and rodents with A. cantonensis was confirmed through morphological and morphometrical analyses of adults and larvae using light microscopy, scanning electron microscopy and molecular sequences of partial Cytochrome Oxidase subunit I. Phylogenetic analyses showed that A. cantonensis isolated from Pará, Brazil is similar to Japan isolate; once these specimens produced a single haplotype with high bootstrap support with Rio de Janeiro isolate. This study confirms that A. cantonensis is now endemic in northern Brazil, and that R. rattus and R. norvegicus act as natural definitive hosts, and A. fulica as the intermediate host of the parasite in this region. Copyright © 2012 Elsevier B.V. All rights reserved.

L-Phenylalanine and L-tyrosine catabolism by selected Streptomyces species

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pometto, A.L. III; Crawford, D.L.

L-Phenylalanine and L-tyrosine were completely catabolized through homogentisate by Streptomyces setonii 75Vi2 but only partially degraded by Streptomyces badius 252, Streptomyces sioyaensis P5, Streptomyces viridosporus T7A, and Streptomyces sp. strain V7. Intermediates of catabolism were confirmed by the thin-layer, gas, and high-pressure liquid chromatography. Homogentisate 1,2-dioxygenase was present in all cell extracts.

L-Phenylalanine and L-tyrosine catabolism by selected Streptomyces species.

PubMed Central

Pometto, A L; Crawford, D L

1985-01-01

L-Phenylalanine and L-tyrosine were completely catabolized through homogentisate by Streptomyces setonii 75Vi2 but only partially degraded by Streptomyces badius 252, Streptomyces sioyaensis P5, Streptomyces viridosporus T7A, and Streptomyces sp. strain V7. Intermediates of catabolism were confirmed by thin-layer, gas, and high-pressure liquid chromatography. Homogentisate 1,2-dioxygenase was present in all cell extracts. PMID:3994376

Identification and subsequent phosphorylation of sequestered partially processed caseins in the lactating guinea-pig mammary gland.

PubMed Central

Boulton, A P; Pascall, J C; Craig, R K

1984-01-01

Golgi and endoplasmic-reticulum fractions were prepared from the lactating guinea-pig mammary gland. The endoplasmic-reticulum fraction was highly active in the processing and sequestration of milk-protein primary translation products. Explants from the lactating gland in organ culture were used to identify milk-protein intermediates present in the secretory pathway, and the timing of the events leading to their post-translational modification. With [35S]methionine, the milk proteins labelled after a short pulse (3 min) were represented by the partially processed (but not phosphorylated) caseins and alpha-lactalbumin sequestered within membrane-bound vesicles. After a 30 min labelling period, higher-Mr caseins with electrophoretic mobilities identical with those of the phosphorylated caseins isolated from milk were identified in the incubation medium, and sequestered within membrane-bound vesicles. Pulse-chase experiments established a precursor-product relationship between these forms. Secretion is apparent approx. 30 min after sequestration. Caseins are highly phosphorylated; removal of the phosphate residues with acid phosphatase results in proteins with increased electrophoretic mobility, similar to those of the partially processed early casein intermediates found sequestered in explants after a 3 min pulse with [35S]methionine, and those sequestered within microsomal membranes after mRNA-directed cell-free protein synthesis. A comparison of the proteins labelled during both short (5 min) and long (30 min) pulses with [35S]methionine and [32P]Pi shows that, in contrast with the 35S-labelled caseins, those labelled with [32P]Pi exhibit only electrophoretic mobilities identical with those of the mature caseins isolated from milk and those identified after long labelling periods with [35S]methionine. No phosphorylated early intermediate forms of caseins were identified. We conclude that the synthesis and post-translational modification of guinea-pig caseins occurs in two stages, (i) an early event involving synthesis and sequestration within the endoplasmic reticulum, an event that involves signal-peptide removal, followed (ii) 10-20 min later by phosphorylation at a different point in the secretory pathway, probably in the Golgi complex. Secretion of the phosphorylated caseins occurs 10-20 min later. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. PMID:6477529

Method of making metal oxide ceramic powders by using a combustible amino acid compound

DOEpatents

Pederson, L.R.; Chick, L.A.; Exarhos, G.J.

1992-05-19

This invention is directed to the formation of homogeneous, aqueous precursor mixtures of at least one substantially soluble metal salt and a substantially soluble, combustible co-reactant compound, typically an amino acid. This produces, upon evaporation, a substantially homogeneous intermediate material having a total solids level which would support combustion. The homogeneous intermediate material essentially comprises highly dispersed or solvated metal constituents and the co-reactant compound. The intermediate material is quite flammable. A metal oxide powder results on ignition of the intermediate product which combusts same to produce the product powder.

Method of making metal oxide ceramic powders by using a combustible amino acid compound

DOEpatents

Pederson, Larry R.; Chick, Lawrence A.; Exarhos, Gregory J.

1992-01-01

This invention is directed to the formation of homogeneous, aqueous precursor mixtures of at least one substantially soluble metal salt and a substantially soluble, combustible co-reactant compound, typically an amino acid. This produces, upon evaporation, a substantially homogeneous intermediate material having a total solids level which would support combustion. The homogeneous intermediate material essentially comprises highly dispersed or solvated metal constituents and the co-reactant compound. The intermediate material is quite flammable. A metal oxide powder results on ignition of the intermediate product which combusts same to produce the product powder.

Evidence for a Shared Mechanism in the Formation of Urea-Induced Kinetic and Equilibrium Intermediates of Horse Apomyoglobin from Ultrarapid Mixing Experiments

PubMed Central

Mizukami, Takuya; Abe, Yukiko; Maki, Kosuke

2015-01-01

In this study, the equivalence of the kinetic mechanisms of the formation of urea-induced kinetic folding intermediates and non-native equilibrium states was investigated in apomyoglobin. Despite having similar structural properties, equilibrium and kinetic intermediates accumulate under different conditions and via different mechanisms, and it remains unknown whether their formation involves shared or distinct kinetic mechanisms. To investigate the potential mechanisms of formation, the refolding and unfolding kinetics of horse apomyoglobin were measured by continuous- and stopped-flow fluorescence over a time range from approximately 100 μs to 10 s, along with equilibrium unfolding transitions, as a function of urea concentration at pH 6.0 and 8°C. The formation of a kinetic intermediate was observed over a wider range of urea concentrations (0–2.2 M) than the formation of the native state (0–1.6 M). Additionally, the kinetic intermediate remained populated as the predominant equilibrium state under conditions where the native and unfolded states were unstable (at ~0.7–2 M urea). A continuous shift from the kinetic to the equilibrium intermediate was observed as urea concentrations increased from 0 M to ~2 M, which indicates that these states share a common kinetic folding mechanism. This finding supports the conclusion that these intermediates are equivalent. Our results in turn suggest that the regions of the protein that resist denaturant perturbations form during the earlier stages of folding, which further supports the structural equivalence of transient and equilibrium intermediates. An additional folding intermediate accumulated within ~140 μs of refolding and an unfolding intermediate accumulated in <1 ms of unfolding. Finally, by using quantitative modeling, we showed that a five-state sequential scheme appropriately describes the folding mechanism of horse apomyoglobin. PMID:26244984

76 FR 13629 - Draft Guidance for Industry on Chemistry, Manufacturing, and Controls Information-Fermentation...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-14

...] Draft Guidance for Industry on Chemistry, Manufacturing, and Controls Information--Fermentation-Derived... Controls (CMC) Information-- Fermentation-Derived Intermediates, Drug Substances, and Related Drug Products... documentation to submit to support the CMC information for fermentation-derived intermediates, drug substances...

Reversible Aggregation Plays a Crucial Role on the Folding Landscape of p53 Core Domain

PubMed Central

Ishimaru, Daniella; Lima, Luis M. T. R.; Maia, Lenize F.; Lopez, Priscila M.; Ano Bom, Ana P.; Valente, Ana P.; Silva, Jerson L.

2004-01-01

The role of tumor suppressor protein p53 in cell cycle control depends on its flexible and partially unstructured conformation, which makes it crucial to understand its folding landscape. Here we report an intermediate structure of the core domain of the tumor suppressor protein p53 (p53C) during equilibrium and kinetic folding/unfolding transitions induced by guanidinium chloride. This partially folded structure was undetectable when investigated by intrinsic fluorescence. Indeed, the fluorescence data showed a simple two-state transition. On the other hand, analysis of far ultraviolet circular dichroism in 1.0 M guanidinium chloride demonstrated a high content of secondary structure, and the use of an extrinsic fluorescent probe, 4,4′-dianilino-1,1′ binaphthyl-5,5′-disulfonic acid, indicated an increase in exposure of the hydrophobic core at 1 M guanidinium chloride. This partially folded conformation of p53C was plagued by aggregation, as suggested by one-dimensional NMR and demonstrated by light-scattering and gel-filtration chromatography. Dissociation by high pressure of these aggregates reveals the reversibility of the process and that the aggregates have water-excluded cavities. Kinetic measurements show that the intermediate formed in a parallel reaction between unfolded and folded structures and that it is under fine energetic control. They are not only crucial to the folding pathway of p53C but may explain as well the vulnerability of p53C to undergo departure of the native to an inactive state, which makes the cell susceptible to malignant transformation. PMID:15298872

Successful infection control for a vancomycin-intermediate Staphylococcus aureus outbreak in an advanced emergency medical service centre.

PubMed

Sakai, Y; Qin, L; Miura, M; Masunaga, K; Tanamachi, C; Iwahashi, J; Kida, Y; Takasu, O; Sakamoto, T; Watanabe, H

2016-04-01

A vancomycin-intermediate Staphylococcus aureus (VISA) (vancomycin minimum inhibitory concentration: 4mg/L) outbreak occurred in an advanced emergency medical service centre [hereafter referred to as the intensive care unit (ICU)] between 2013 and 2014. Our objective was to evaluate the infection control measures that were successful. Seventeen VISA strains were isolated from the sputum of 15 inpatients and the skin of two inpatients. Fourteen VISA strains were recognized as colonization. However, three VISA strains were isolated from the sputum of three inpatients with pneumonia. Environmental cultures were performed and VISA strains were detected in five of 65 sites. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) was performed on 21 VISA strains. Molecular typing including PFGE and MLST showed that the patterns of 19 VISA strains were identical and those of the other two VISA strains were possibly related. This meant that a horizontal transmission of VISA strains had occurred in the ICU. In August 2013, the infection control team began interventions. However, new inpatients with VISA strains continued to appear. Therefore, in October 2013, the ICU was partially closed in order to try to prevent further horizontal transmission, and existing inpatients with the VISA strain were isolated. Although new cases quickly dissipated after the partial closure, it took approximately five months to eradicate the VISA outbreak. Our data suggest that despite the employment of various other infection control measures, partial closure of the ICU was essential in terminating this VISA outbreak. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Folding of the RNA Recognition Motif (RRM) Domains of the Amyotrophic Lateral Sclerosis (ALS)-linked Protein TDP-43 Reveals an Intermediate State*

PubMed Central

Mackness, Brian C.; Tran, Meme T.; McClain, Shannan P.; Matthews, C. Robert; Zitzewitz, Jill A.

2014-01-01

Pathological alteration of TDP-43 (TAR DNA-binding protein-43), a protein involved in various RNA-mediated processes, is a hallmark feature of the neurodegenerative diseases amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Fragments of TDP-43, composed of the second RNA recognition motif (RRM2) and the disordered C terminus, have been observed in cytoplasmic inclusions in sporadic amyotrophic lateral sclerosis cases, suggesting that conformational changes involving RRM2 together with the disordered C terminus play a role in aggregation and toxicity. The biophysical data collected by CD and fluorescence spectroscopies reveal a three-state equilibrium unfolding model for RRM2, with a partially folded intermediate state that is not observed in RRM1. Strikingly, a portion of RRM2 beginning at position 208, which mimics a cleavage site observed in patient tissues, increases the population of this intermediate state. Mutually stabilizing interactions between the domains in the tethered RRM1 and RRM2 construct reduce the population of the intermediate state and enhance DNA/RNA binding. Despite the high sequence homology of the two domains, a network of large hydrophobic residues in RRM2 provides a possible explanation for the increased stability of RRM2 compared with RRM1. The cluster analysis suggests that the intermediate state may play a functional role by enhancing access to the nuclear export signal contained within its sequence. The intermediate state may also serve as a molecular hazard linking productive folding and function with pathological misfolding and aggregation that may contribute to disease. PMID:24497641

Evaluating the effects of trophic complexity on a keystone predator by disassembling a partial intraguild predation food web.

PubMed

Davenport, Jon M; Chalcraft, David R

2012-01-01

1. Many taxa can be found in food webs that differ in trophic complexity, but it is unclear how trophic complexity affects the performance of particular taxa. In pond food webs, larvae of the salamander Ambystoma opacum occupy the intermediate predator trophic position in a partial intraguild predation (IGP) food web and can function as keystone predators. Larval A. opacum are also found in simpler food webs lacking either top predators or shared prey. 2. We conducted an experiment where a partial IGP food web was simplified, and we measured the growth and survival of larval A. opacum in each set of food webs. Partial IGP food webs that had either a low abundance or high abundance of total prey were also simplified by independently removing top predators and/or shared prey. 3. Removing top predators always increased A. opacum survival, but removal of shared prey had no effect on A. opacum survival, regardless of total prey abundance. 4. Surprisingly, food web simplification had no effect on the growth of A. opacum when present in food webs with a low abundance of prey but had important effects on A. opacum growth in food webs with a high abundance of prey. Simplifying a partial IGP food web with a high abundance of prey reduced A. opacum growth when either top predators or shared prey were removed from the food web and the loss of top predators and shared prey influenced A. opacum growth in a non-additive fashion. 5. The non-additive response in A. opacum growth appears to be the result of supplemental prey availability augmenting the beneficial effects of top predators. Top predators had a beneficial effect on A. opacum populations by reducing the abundance of A. opacum present and thereby reducing the intensity of intraspecific competition. 6. Our study indicates that the effects of food web simplification on the performance of A. opacum are complex and depend on both how a partial IGP food web is simplified and how abundant prey are in the food web. These findings are important because they demonstrate how trophic complexity can create variation in the performance of intermediate predators that play important roles in temporary pond food webs. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.

Evolution of learning in fluctuating environments: when selection favors both social and exploratory individual learning.

PubMed

Borenstein, Elhanan; Feldman, Marcus W; Aoki, Kenichi

2008-03-01

Cumulative cultural change requires organisms that are capable of both exploratory individual learning and faithful social learning. In our model, an organism's phenotype is initially determined innately (by its genotypic value) or by social learning (copying a phenotype from the parental generation), and then may or may not be modified by individual learning (exploration around the initial phenotype). The environment alternates periodically between two states, each defined as a certain range of phenotypes that can survive. These states may overlap, in which case the same phenotype can survive in both states, or they may not. We find that a joint social and exploratory individual learning strategy-the strategy that supports cumulative culture-is likely to spread when the environmental states do not overlap. In particular, when the environmental states are contiguous and mutation is allowed among the genotypic values, this strategy will spread in either moderately or highly stable environments, depending on the exact nature of the individual learning applied. On the other hand, natural selection often favors a social learning strategy without exploration when the environmental states overlap. We find only partial support for the "consensus" view, which holds that individual learning, social learning, and innate determination of behavior will evolve at short, intermediate, and long environmental periodicities, respectively.

Long-term dynamic and pseudo-state modeling of complete partial nitrification process at high nitrogen loading rates in a sequential batch reactor (SBR).

PubMed

Soliman, Moomen; Eldyasti, Ahmed

2017-06-01

Recently, partial nitrification has been adopted widely either for the nitrite shunt process or intermediate nitrite generation step for the Anammox process. However, partial nitrification has been hindered by the complexity of maintaining stable nitrite accumulation at high nitrogen loading rates (NLR) which affect the feasibility of the process for high nitrogen content wastewater. Thus, the operational data of a lab scale SBR performing complete partial nitrification as a first step of nitrite shunt process at NLRs of 0.3-1.2kg/(m 3 d) have been used to calibrate and validate a process model developed using BioWin® in order to describe the long-term dynamic behavior of the SBR. Moreover, an identifiability analysis step has been introduced to the calibration protocol to eliminate the needs of the respirometric analysis for SBR models. The calibrated model was able to predict accurately the daily effluent ammonia, nitrate, nitrite, alkalinity concentrations and pH during all different operational conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Foreign Object Damage Behavior of a SiC/SiC Composite at Ambient and Elevated Temperatures

NASA Technical Reports Server (NTRS)

Bhatt, Ramakrishna T.; Pereira, J. Michael; Gyekenyesi, John P.; Choi, Sung R.

2004-01-01

Foreign object damage (FOD) behavior of a gas-turbine grade SiC/SiC ceramic matrix composite (CMC) was determined at 25 and 1316 C, employing impact velocities from 115 to 440 meters per second by 1.59-mm diameter stell-ball projectiles. Two different types of specimen support were used at each temperature: fully supported and partially supported. For a given temperature, the degree of post-impact strength degradation increased with increasing impact velocity, and was greater in a partially supported configuration than in a fully supported one. The elevated-temperature FOD resistance of the composite, particularly under partially supported loading at higher impact velocities greater than or equal to 350 meters per second, was significantly less than the ambient-temperature counterpart, attributed to a weakening effect of the composite. For fully supported loading, frontal contact stress played a major role in generating composite damage; whereas, for partially supported loading, both frontal contact and backside bending stresses were combined sources of damage generation. The SiC/SiC composite was able to survive higher energy impacts without complete structural failure but suffered more strength affecting damage from low energy impacts than AS800 and SN282 silicon nitrides.

Improving Orientation Outcomes: Implementation of Phased Orientation Process in an Intermediate Special Care Nursery.

PubMed

Rivera, Emily K; Shedenhelm, Heidi J; Gibbs, Ardyce L

2015-01-01

In response to changing needs of registered nurse orientees, the staff education committee in the Intermediate Special Care Nursery has implemented a phased orientation process. This phased process includes a mentoring experience postorientation to support a new nurse through the first year of employment. Since implementing the phased orientation process in the Intermediate Special Care Nursery, orientee satisfaction and preparation to practice have increased, and length of orientation has decreased.

Case and Administrative Support Tools

EPA Pesticide Factsheets

Case and Administrative Support Tools (CAST) is the secure portion of the Office of General Counsel (OGC) Dashboard business process automation tool used to help reduce office administrative labor costs while increasing employee effectiveness. CAST supports business functions which rely on and store Privacy Act sensitive data (PII). Specific business processes included in CAST (and respective PII) are: -Civil Rights Cast Tracking (name, partial medical history, summary of case, and case correspondance). -Employment Law Case Tracking (name, summary of case). -Federal Tort Claims Act Incident Tracking (name, summary of incidents). -Ethics Program Support Tools and Tracking (name, partial financial history). -Summer Honors Application Tracking (name, home address, telephone number, employment history). -Workforce Flexibility Initiative Support Tools (name, alternative workplace phone number). -Resource and Personnel Management Support Tools (name, partial employment and financial history).

Transformation of bisphenol A in water distribution systems: a pilot-scale study.

PubMed

Li, Cong; Wang, Zilong; Yang, Y Jeffrey; Liu, Jingqing; Mao, Xinwei; Zhang, Yan

2015-04-01

Halogenations of bisphenol A (BPA) in a pilot-scale water distribution system (WDS) of a cement-lined ductile cast iron pipe were investigated. The water in the pilot-scale WDS was chlorinated with a free chlorine concentration of 0.7 mg L(-1) using sodium hypochlorite, and with an initial BPA concentration of 100 μg L(-1) was spiked in the WDS. Halogenated compounds in the BPA experiments were identified using EI/GC/MS and GC. Several BPA congeners, including 2-chlorobisphenol A (MCBPA), dichlorobisphenol A (D2-CBPA), 2,2',6-trichlorobisphenol A (T3CBPA), 2,2',6,6'-tetrachlorobisphenol A (T4CBPA), 2-bromobisphenol A (MBBPA), and bromochlorobisphenol A (MBMCBPA) were found. Moreover, further halogenation yielded other reaction intermediates, including 2,4,6-trichlorophenol (T3CP), dichlorobisphenol A, bromodichlorophenol, and dibromochlorophenol. After halogenation for 120min, most of the abovementioned reaction intermediates disappeared and were replaced by trihalomethanes (THMs). Based on these experimental findings, the halogenation process of BPA oxidation in a WDS includes three stages: (1) halogenation on the aromatic ring; (2) chlorine or bromine substitution followed by cleavage of the α-C bond on the isopropyl moiety with a positive partial charge and a β'-C bond on the benzene moiety with a negative partial charge; and (3) THMs and a minor HAA formation from phenolic intermediates through the benzene ring opening with a chlorine and bromine substitution of the hydrogen on the carbon atoms. The oxidation mechanisms of the entire transformation from BPA to THM/HAA in the WDS were proposed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Aromatic residues engineered into the beta-turn nucleation site of ubiquitin lead to a complex folding landscape, non-native side-chain interactions, and kinetic traps.

PubMed

Rea, Anita M; Simpson, Emma R; Meldrum, Jill K; Williams, Huw E L; Searle, Mark S

2008-12-02

The fast folding of small proteins is likely to be the product of evolutionary pressures that balance the search for native-like contacts in the transition state with the minimum number of stable non-native interactions that could lead to partially folded states prone to aggregation and amyloid formation. We have investigated the effects of non-native interactions on the folding landscape of yeast ubiquitin by introducing aromatic substitutions into the beta-turn region of the N-terminal beta-hairpin, using both the native G-bulged type I turn sequence (TXTGK) as well as an engineered 2:2 XNGK type I' turn sequence. The N-terminal beta-hairpin is a recognized folding nucleation site in ubiquitin. The folding kinetics for wt-Ub (TLTGK) and the type I' turn mutant (TNGK) reveal only a weakly populated intermediate, however, substitution with X = Phe or Trp in either context results in a high propensity to form a stable compact intermediate where the initial U-->I collapse is visible as a distinct kinetic phase. The introduction of Trp into either of the two host turn sequences results in either complex multiphase kinetics with the possibility of parallel folding pathways, or formation of a highly compact I-state stabilized by non-native interactions that must unfold before refolding. Sequence substitutions with aromatic residues within a localized beta-turn capable of forming non-native hydrophobic contacts in both the native state and partially folded states has the undesirable consequence that folding is frustrated by the formation of stable compact intermediates that evolutionary pressures at the sequence level may have largely eliminated.

DETECTION OF THE INTERMEDIATE-WIDTH EMISSION LINE REGION IN QUASAR OI 287 WITH THE BROAD EMISSION LINE REGION OBSCURED BY THE DUSTY TORUS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zhenzhen; Zhou, Hongyan; Wang, Huiyuan

2015-10-20

The existence of intermediate-width emission line regions (IELRs) in active galactic nuclei has been discussed for over two decades. A consensus, however, is yet to be arrived at due to the lack of convincing evidence for their detection. We present a detailed analysis of the broadband spectrophotometry of the partially obscured quasar OI 287. The ultraviolet intermediate-width emission lines (IELs) are very prominent, in high contrast to the corresponding broad emission lines (BELs) which are heavily suppressed by dust reddening. Assuming that the IELR is virialized, we estimated its distance to the central black hole to be ∼2.9 pc, similarmore » to the dust sublimation radius of ∼1.3 pc. Photo-ionization calculations suggest that the IELR has a hydrogen density of ∼10{sup 8.8}–10{sup 9.4} cm{sup −3}, within the range of values quoted for the dusty torus near the sublimation radius. Both its inferred location and physical conditions suggest that the IELR originates from the inner surface of the dusty torus. In the spectrum of this quasar, we identified only one narrow absorption-line system associated with the dusty material. With the aid of photo-ionization model calculations, we found that the obscuring material might originate from an outer region of the dusty torus. We speculate that the dusty torus, which is exposed to the central ionizing source, may produce IELs through photo-ionization processes, as well as obscure BELs as a natural “coronagraph.” Such a “coronagraph” could be found in a large number of partially obscured quasars and may be a useful tool to study IELRs.« less

Can a Modified Bosniak Classification System Risk Stratify Pediatric Cystic Renal Masses?

PubMed

Saltzman, Amanda F; Carrasco, Alonso; Colvin, Alexandra N; Meyers, Mariana L; Cost, Nicholas G

2018-03-20

We characterize and apply the modified Bosniak classification system to a cohort of children with cystic renal lesions and known surgical pathology. We identified all patients at our institution with cystic renal masses who also underwent surgery for these lesions. Patients without available preoperative imaging or pathology were excluded. All radiological imaging was independently reviewed by a pediatric radiologist blinded to pathological findings. Imaging characteristics (size, border, septations, calcifications, solid components, vascularity) were recorded from the most recent preoperative ultrasounds and computerized tomograms. The modified Bosniak classification system was applied to these scans and then correlated with final pathology. A total of 22 patients met study criteria. Median age at surgery was 6.1 years (range 11 months to 16.8 years). Of the patients 12 (54.5%) underwent open nephrectomy, 6 (27.3%) open partial nephrectomy, 2 (9.1%) laparoscopic cyst decortication, 1 (4.5%) open renal biopsy and 1 (4.5%) laparoscopic partial nephrectomy. Final pathology was benign in 9 cases (41%), intermediate in 6 (27%) and malignant in 7 (32%). All malignant lesions were modified Bosniak class 4, all intermediate lesions were modified class 3 or 4 and 8 of 9 benign lesions (89%) were modified class 1 or 2. Cystic renal lesions in children with a modified Bosniak class of 1 or 2 were most often benign, while class 3 or 4 lesions warranted surgical excision since more than 90% of masses harbored intermediate or malignant pathology. The modified Bosniak classification system appears to allow for a reasonable clinical risk stratification of pediatric cystic renal masses. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

A prospective randomized study of Chop versus Chop plus alpha-2B interferon in patients with intermediate and high grade non-Hodgkin's lymphoma: the International Oncology Study Group NHL1 Study .

PubMed

Giles, F J; Shan, J; Advani, S H; Akan, H; Aydogdu, I; Aziz, Z; Azim, H A; Bapsy, P P; Buyukkececi, F; Chaimongkol, B; Chen, P M; Cheong, S K; Ferhanoglu, B; Hamza, R; Khalid, H M; Intragumtornchai, T; Kim, S W; Kim, S Y; Koc, H; Kumar, L; Kumar, R; Lei, K I; Lekhakula, A; Muthalib, A; Patel, M; Poovalingam, V P; Prayoonwiwat, W; Rana, F; Reksodiputro, A H; Ruff, P; Sagar, T G; Schwarer, A P; Song, H S; Suh, C W; Suharti, C; Supindiman, I; Tee, G Y; Thamprasit, T; Villalon, A H; Wickham, N R; Wong, J E; Yalcin, A; Jootar, S

2000-12-01

The addition of a brief alpha interferon regimen to each CHOP induction cycle, plus one year of alpha interferon thrice weekly maintenance therapy, has no early effect on response rates or survival in patients with Intermediate or High grade cell NHL. The CHOP (Cyclophosphamide, Adriamycin. Vincristine, Prednisone) regimen is the most widely used first-line therapy for patients with Intermediate or High Grade (IG/HG) non-Hodgkin's lymphoma (NHL). Alpha 2b interferon (INF) enhances response rates and improves survival in low-grade NHL. The International Oncology Study Group (IOSG) conducted a prospective randomized study comparing CHOP alone or combined with INF in patients with IG/HG-NHL. The primary study aim was to compare the objective response rates in these patient cohorts. Patients with a confirmed diagnosis of measurable NHL of International Working Formulation (IWF) groups D to H histology were randomized to receive CHOP alone or CHOP with 5Mu INF s.c. for 5 days on days 22 to 26 of each 28 day cycle with INF 5 million units (Mu) given three times per week subcutaneously for 52 weeks in those patients who responded to CHOP plus INF. The overall response rates were equivalent in both groups: CHOP alone (214 patients) 81% (complete 55%, partial 26%); CHOP plus INF (221 patients) 80% (complete 54%, partial 26%). At 36 months, the actuarial survival rate was equivalent in both groups. There is no apparent early advantage in terms of response or survival conferred by adding the study INF regimen to CHOP therapy for patients with IG/HG-NHL.

Intracellular processing, glycosylation, and cell surface expression of human metapneumovirus attachment glycoprotein.

PubMed

Liu, Li; Bastien, Nathalie; Li, Yan

2007-12-01

The biosynthesis and posttranslational processing of human metapneumovirus attachment G glycoprotein were investigated. After pulse-labeling, the G protein accumulated as three species with molecular weights of 45,000, 50,000, and 53,000 (45K, 50K, and 53K, respectively). N-Glycosidase digestion indicated that these forms represent the unglycosylated precursor and N-glycosylated intermediate products, respectively. After an appropriate chase, these three naive forms were further processed to a mature 97K form. The presence of O-linked sugars in mature G protein was confirmed by O-glycanase digestion and lectin-binding assay using Arachis hypogaea (peanut agglutinin), an O-glycan-specific lectin. In addition, in the O-glycosylation-deficient cell line (CHO ldlD cell), the G protein could not be processed to the mature form unless the exogenous Gal and GalNAc were supplemented, which provided added evidence supporting the O-linked glycosylation of G protein. The maturation of G was completely blocked by monensin but was partially sensitive to brefeldin A (BFA), suggesting the O-linked glycosylation of G initiated in the trans-Golgi compartment and terminated in the trans-Golgi network. Enzymatic deglycosylation analysis confirmed that the BFA-G was a partial mature form containing N-linked oligosaccharides and various amounts of O-linked carbohydrate side chains. The expression of G protein at the cell surface could be detected by indirect immunofluorescence staining assay. Furthermore, cell surface immunoprecipitation displayed an efficient intracellular transport of G protein.

Chain elongation and cyclization in type III PKS DpgA.

PubMed

Wu, Hai-Chen; Li, Yi-San; Liu, Yu-Chen; Lyu, Syue-Yi; Wu, Chang-Jer; Li, Tsung-Lin

2012-04-16

Chain elongation and cyclization of precursors of dihydroxyphenylacetyl-CoA (DPA-CoA) catalyzed by the bacterial type III polyketide synthase DpgA were studied. Two labile intermediates, di- and tri-ketidyl-CoA (DK- and TK-CoA), were proposed and chemically synthesized. In the presence of DpgABD, each of these with [(13)C(3)]malonyl-CoA (MA-CoA) was able to form partially (13)C-enriched DPA-CoA. By NMR and MS analysis, the distribution of (13)C atoms in the partially (13)C-enriched DPA-CoA shed light on how the polyketide chain elongates and cyclizes in the DpgA-catalyzed reaction. Polyketone intermediates elongate in a manner different from that which had been believed: two molecules of DK-CoA, or one DK-CoA plus one acetoacetyl-CoA (AA-CoA), but not two molecules of AA-CoA can form one molecule of DPA-CoA. As a result, polyketidyl-CoA serves as both the starter and extender, whereas polyketone-CoA without the terminal carboxyl group can only act as an extender. The terminal carboxyl group is crucial for the cyclization that likely takes place on CoA. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Decoding Structural Properties of a Partially Unfolded Protein Substrate: En Route to Chaperone Binding.

PubMed

Nagpal, Suhani; Tiwari, Satyam; Mapa, Koyeli; Thukral, Lipi

2015-01-01

Many proteins comprising of complex topologies require molecular chaperones to achieve their unique three-dimensional folded structure. The E.coli chaperone, GroEL binds with a large number of unfolded and partially folded proteins, to facilitate proper folding and prevent misfolding and aggregation. Although the major structural components of GroEL are well defined, scaffolds of the non-native substrates that determine chaperone-mediated folding have been difficult to recognize. Here we performed all-atomistic and replica-exchange molecular dynamics simulations to dissect non-native ensemble of an obligate GroEL folder, DapA. Thermodynamics analyses of unfolding simulations revealed populated intermediates with distinct structural characteristics. We found that surface exposed hydrophobic patches are significantly increased, primarily contributed from native and non-native β-sheet elements. We validate the structural properties of these conformers using experimental data, including circular dichroism (CD), 1-anilinonaphthalene-8-sulfonic acid (ANS) binding measurements and previously reported hydrogen-deutrium exchange coupled to mass spectrometry (HDX-MS). Further, we constructed network graphs to elucidate long-range intra-protein connectivity of native and intermediate topologies, demonstrating regions that serve as central "hubs". Overall, our results implicate that genomic variations (or mutations) in the distinct regions of protein structures might disrupt these topological signatures disabling chaperone-mediated folding, leading to formation of aggregates.

Cobalt (II) oxide and nickel (II) oxide alloys as potential intermediate-band semiconductors: A theoretical study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alidoust, Nima; Lessio, Martina; Carter, Emily A., E-mail: eac@princeton.edu

2016-01-14

Solar cells based on single pn junctions, employing single-gap semiconductors can ideally achieve efficiencies as high as 34%. Developing solar cells based on intermediate-band semiconductors (IBSCs), which can absorb light across multiple band gaps, is a possible way to defy this theoretical limit and achieve efficiencies as high as 60%. Here, we use first principles quantum mechanics methods and introduce CoO and Co{sub 0.25}Ni{sub 0.75}O as possible IBSCs. We show that the conduction band in both of these materials is divided into two distinct bands separated by a band gap. We further show that the lower conduction band (i.e., themore » intermediate band) is wider in Co{sub 0.25}Ni{sub 0.75}O compared with CoO. This should enhance light absorption from the valence band edge to the intermediate band, making Co{sub 0.25}Ni{sub 0.75}O more appropriate for use as an IBSC. Our findings provide the basis for future attempts to partially populate the intermediate band and to reduce the lower band gap in Co{sub 0.25}Ni{sub 0.75}O in order to enhance the potential of this material for use in IBSC solar cell technologies. Furthermore, with proper identification of heterojunctions and dopants, CoO and Co{sub 0.25}Ni{sub 0.75}O could be used in multi-color light emitting diode and laser technologies.« less

Transformations of C2-C4 alcohols on the surface of a copper catalyst

NASA Astrophysics Data System (ADS)

Magaeva, A. A.; Lyamina, G. V.; Sudakova, N. N.; Shilyaeva, L. P.; Vodyankina, O. V.

2007-10-01

The interaction of monoatomic alcohols C2-C4 with the surface of a copper catalyst preliminarily oxidized under various conditions was studied by the temperature-programmed reaction method to determine the detailed mechanism of partial oxidation. The conditions of oxygen preadsorption on the surface of copper for the preparation of the desired products were determined. The selective formation of carbonyl compounds was shown to occur at the boundary between reduced and oxidized copper surface regions. The role played by Cu2O was the deep oxidation of alcohols to CO2. Alcohols with branched hydrocarbon structures experienced parallel partial oxidation and dehydrogenation, which was related to the high stability of intermediate keto-type compounds.

Understanding curcumin-induced modulation of protein aggregation.

PubMed

Ahmad, Basir; Borana, Mohanish S; Chaudhary, Ankur P

2017-07-01

Curcumin, a diarylheptanoid compound, found in spice turmeric is known to alter the aggregation of proteins and reduce the toxicity of the aggregates. This review looks at the molecular basis of modulating protein aggregation and toxicity of the aggregates. Foremost, we identify the interaction of curcumin and its derivatives with proteins/peptides and the effect of their interaction on the conformational stability and unfolding/folding pathway(s). The unfolding/folding processes generate partially folded/unfolded intermediate, which serve as aggregation precursor state. Secondly, we discuss the effect of curcumin binding on the kinetics parameters of the aggregation process, which give information about the mechanism of the aggregation inhibition. We describe, in addition, that curcumin can accelerate/promote fibril formation by binding to oligomeric intermediate(s) accumulated in the aggregation pathway. Finally, we discuss the correlation of curcumin-induced monomeric and/or oligomeric precursor states with aggregate structure and toxicity. On the basis of these discussions, we propose a model describing curcumin-induced inhibition/promotion of formation of amyloid-like fibrils. Copyright © 2016 Elsevier B.V. All rights reserved.

Production of lignin based insoluble polymers (anionic hydrogels) by C. versicolor.

PubMed

Brzonova, Ivana; Kozliak, Evguenii I; Andrianova, Anastasia A; LaVallie, Audrey; Kubátová, Alena; Ji, Yun

2017-12-13

Unlike previous lignin biodegradation studies, white rot fungi were used to produce functional biopolymers from Kraft lignin. Lignin-based polymers (hydrogel precursors) partially soluble in both aqueous and organic solvents were produced employing a relatively fast (6 days) enzymation of Kraft lignin with basidiomycetes, primarily Coriolus versicolor, pre-grown on kenaf/lignin agar followed by either vacuum evaporation or acid precipitation. After drying followed by a treatment with alkaline water, this intermediate polymer became a pH-sensitive anionic hydrogel insoluble in either aqueous or organic solvents. The yield of this polymer increased from 20 to 72 wt% with the addition of 2% dimethylsulfoxide to distilled water used as a medium. The mechanical stability and buffering capacity of this hydrogel can be adjusted by washing the intermediate polymer/hydrogel precursor prior to drying with solvents of different polarity (water, methanol or ethanol). Any of these polymers featured a significant thermal resilience assessed as a high thermostable "coked" fraction in thermal carbon analysis, apparently resulting from significant covalent cross-linking that occurs during the treatment of their intermediate precursors.

A novel family of Nb-doped Bi0.5Sr0.5FeO3-δ perovskite as cathode material for intermediate-temperature solid oxide fuel cells

NASA Astrophysics Data System (ADS)

Gao, Lei; Li, Qiang; Sun, Liping; Zhang, Xianfa; Huo, Lihua; Zhao, Hui; Grenier, Jean-Claude

2017-12-01

Cobalt-free provskite oxides Bi0.5Sr0.5Fe1-xNbxO3-δ (BSFNx, x = 0.05, 0.10 and 0.15) were prepared and evaluated as cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs). In particular, the effects of Nb substitution on phase evolution, thermal expansion behavior and electrochemical performance were systematically investigated. The average thermal expansion coefficient (TEC) of BSFNx decreases from 13.3 × 10-6 K-1 at x = 0.05 to 12.6 × 10-6 K-1 at x = 0.15 within a temperature range of 50-800 °C. Among the BSFNx materials, Bi0.5Sr0.5Fe0.9Nb0.1O3-δ (BSFN0.10) oxide shows the best electrochemical performance. The polarization resistances (Rp) of BSFN0.10 cathode on CGO electrolyte are 0.038, 0.075 and 0.156 Ω cm2 at 700, 650 and 600 °C, respectively. Meanwhile the maximum power densities of the anode-supported single cells are 1.28, 1.54 and 1.34 W cm-2 at 700 °C for BSFNx cathodes with x = 0.05, 0.10, and 0.15, respectively. Furthermore, the relationship study of oxygen partial pressure dependence on Rp indicates that the oxygen reduction reaction (ORR) rate-limiting step is the oxygen adsorption-dissociation on the electrode surface. The desirable electrochemical performance demonstrates that BSFNx oxides are potential cathode materials for IT-SOFCs.

An intermediate along the recovery stroke of myosin VI revealed by X-ray crystallography and molecular dynamics.

PubMed

Blanc, Florian; Isabet, Tatiana; Benisty, Hannah; Sweeney, H Lee; Cecchini, Marco; Houdusse, Anne

2018-06-12

Myosins form a class of actin-based, ATPase motor proteins that mediate important cellular functions such as cargo transport and cell motility. Their functional cycle involves two large-scale swings of the lever arm: the force-generating powerstroke, which takes place on actin, and the recovery stroke during which the lever arm is reprimed into an armed configuration. Previous analyses of the prerecovery (postrigor) and postrecovery (prepowerstroke) states predicted that closure of switch II in the ATP binding site precedes the movement of the converter and the lever arm. Here, we report on a crystal structure of myosin VI, called pretransition state (PTS), which was solved at 2.2 Å resolution. Structural analysis and all-atom molecular dynamics simulations are consistent with PTS being an intermediate along the recovery stroke, where the Relay/SH1 elements adopt a postrecovery conformation, and switch II remains open. In this state, the converter appears to be largely uncoupled from the motor domain and explores an ensemble of partially reprimed configurations through extensive, reversible fluctuations. Moreover, we found that the free energy cost of hydrogen-bonding switch II to ATP is lowered by more than 10 kcal/mol compared with the prerecovery state. These results support the conclusion that closing of switch II does not initiate the recovery stroke transition in myosin VI. Rather, they suggest a mechanism in which lever arm repriming would be mostly driven by thermal fluctuations and eventually stabilized by the switch II interaction with the nucleotide in a ratchet-like fashion.

Survival with AGS-003, an autologous dendritic cell-based immunotherapy, in combination with sunitinib in unfavorable risk patients with advanced renal cell carcinoma (RCC): Phase 2 study results.

PubMed

Amin, Asim; Dudek, Arkadiusz Z; Logan, Theodore F; Lance, Raymond S; Holzbeierlein, Jeffrey M; Knox, Jennifer J; Master, Viraj A; Pal, Sumanta K; Miller, Wilson H; Karsh, Lawrence I; Tcherepanova, Irina Y; DeBenedette, Mark A; Williams, W Lee; Plessinger, Douglas C; Nicolette, Charles A; Figlin, Robert A

2015-01-01

AGS-003 is an autologous immunotherapy prepared from fully matured and optimized monocyte-derived dendritic cells, which are co-electroporated with amplified tumor RNA plus synthetic CD40L RNA. AGS-003 was evaluated in combination with sunitinib in an open label phase 2 study in intermediate and poor risk, treatment naïve patients with metastatic clear cell renal cell carcinoma (mRCC). Twenty-one intermediate and poor risk patients were treated continuously with sunitinib (4 weeks on, 2 weeks off per 6 week cycle). After completion of the first cycle of sunitinib, patients were treated with AGS-003 every 3 weeks for 5 doses, then every 12 weeks until progression or end of study. The primary endpoint was to determine the complete response rate. Secondary endpoints included clinical benefit, safety, progression free survival (PFS) and overall survival (OS). Immunologic response was also monitored. Thirteen patients (62%) experienced clinical benefit (9 partial responses, 4 with stable disease); however there were no complete responses in this group of intermediate and poor risk mRCC patients and enrollment was terminated early. Median PFS from registration was 11.2 months (95% CI 6.0, 19.4) and the median OS from registration was 30.2 months (95% CI 9.4, 57.1) for all patients. Seven (33%) patients survived for at least 4.5 years, while five (24%) survived for more than 5 years, including 2 patients who remain progression-free with durable responses for more than 5 years at the time of this report. AGS-003 was well tolerated with only mild injection-site reactions. The most common adverse events were related to expected toxicity from sunitinib therapy. In patients who had sequential samples available for immune monitoring, the magnitude of the increase in the absolute number of CD8(+) CD28(+) CD45RA(-) effector/memory T cells (CTLs) after 5 doses of AGS-003 relative to baseline, correlated with overall survival. AGS-003 in combination with sunitinib was well tolerated and yielded supportive immunologic responses coupled with extension of median and long-term survival in an unselected, intermediate and poor risk prognosis mRCC population. #NCT00678119.

Histopathological Validation of the Surface-Intermediate-Base Margin Score for Standardized Reporting of Resection Technique during Nephron Sparing Surgery.

PubMed

Minervini, Andrea; Campi, Riccardo; Kutikov, Alexander; Montagnani, Ilaria; Sessa, Francesco; Serni, Sergio; Raspollini, Maria Rosaria; Carini, Marco

2015-10-01

The surface-intermediate-base margin score is a novel standardized reporting system of resection techniques during nephron sparing surgery. We validated the surgeon assessed surface-intermediate-base score with microscopic histopathological assessment of partial nephrectomy specimens. Between June and August 2014 data were prospectively collected from 40 consecutive patients undergoing nephron sparing surgery. The surface-intermediate-base score was assigned to all cases. The score specific areas were color coded with tissue margin ink and sectioned for histological evaluation of healthy renal margin thickness. Maximum, minimum and mean thickness of healthy renal margin for each score specific area grade (surface [S] = 0, S = 1 ; intermediate [I] or base [B] = 0, I or B = 1, I or B = 2) was reported. The Mann-Whitney U and Kruskal-Wallis tests were used to compare the thickness of healthy renal margin in S = 0 vs 1 and I or B = 0 vs 1 vs 2 grades, respectively. Maximum, minimum and mean thickness of healthy renal margin was significantly different among score specific area grades S = 0 vs 1, and I or B = 0 vs 1, 0 vs 2 and 1 vs 2 (p <0.001). The main limitations of the study are the low number of the I or B = 1 and I or B = 2 samples and the assumption that each microscopic slide reflects the entire score specific area for histological analysis. The surface-intermediate-base scoring method can be readily harnessed in real-world clinical practice and accurately mirrors histopathological analysis for quantification and reporting of healthy renal margin thickness removed during tumor excision. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Structure–Reactivity Studies, Characterization, and Transformation of Intermediates by Lithium Chloride in the Direct Insertion of Alkyl and Aryl Iodides to Metallic Zinc Powder

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feng, Chao; Easter, Quinn T.; Blum, Suzanne A.

Employment of fluorophore-tagged alkyl and aryl iodides permitted detection of persistent surface intermediates during their direct insertion to commercially available zinc powder. The sensitivity of this subensemble microscopy technique enabled structure–reactivity studies in the formation of intermediates that are present in quantities sufficiently low as to have been undetected previously by traditional ensemble analytical techniques. In these surface intermediates we transformed them using lithium chloride, which lead to the assignment of the mechanistic role of lithium chloride as changing the rate-determining step in the reaction by lowering the barrier for solubilization of these otherwise persistent surface organometallic intermediates. The temperaturemore » dependence/qualitative barrier of the direct insertion step was determined independently from the solubilization step and from the barrier for the overall reaction. Detection of these zinc surface intermediates at the single-molecule level, i.e., of individual surface organometallic species, has been achieved for the first time. Energy dispersive X-ray spectroscopy (EDS) measurements of the elemental composition of the surface of the zinc powder determined that lithium chloride does not clean the surface of the oxides; instead, pretreatment of the surface with TMSCl effects partial removal of surface oxides after the 2 h pretreatment time previously reported in the empirically optimized synthetic procedure. The current limitations of this microscopy approach are also determined and discussed with respect to the addition of solid reagents during in operando imaging. Characterization of the resulting soluble fluorophore-tagged organozinc/LiCl complex by 1H NMR spectroscopy, mass spectrometry, and fluorescence spectroscopy provided insight into its solution dynamics and chemical exchange processes.« less

Structure–Reactivity Studies, Characterization, and Transformation of Intermediates by Lithium Chloride in the Direct Insertion of Alkyl and Aryl Iodides to Metallic Zinc Powder

DOE PAGES

Feng, Chao; Easter, Quinn T.; Blum, Suzanne A.

2017-02-03

Employment of fluorophore-tagged alkyl and aryl iodides permitted detection of persistent surface intermediates during their direct insertion to commercially available zinc powder. The sensitivity of this subensemble microscopy technique enabled structure–reactivity studies in the formation of intermediates that are present in quantities sufficiently low as to have been undetected previously by traditional ensemble analytical techniques. In these surface intermediates we transformed them using lithium chloride, which lead to the assignment of the mechanistic role of lithium chloride as changing the rate-determining step in the reaction by lowering the barrier for solubilization of these otherwise persistent surface organometallic intermediates. The temperaturemore » dependence/qualitative barrier of the direct insertion step was determined independently from the solubilization step and from the barrier for the overall reaction. Detection of these zinc surface intermediates at the single-molecule level, i.e., of individual surface organometallic species, has been achieved for the first time. Energy dispersive X-ray spectroscopy (EDS) measurements of the elemental composition of the surface of the zinc powder determined that lithium chloride does not clean the surface of the oxides; instead, pretreatment of the surface with TMSCl effects partial removal of surface oxides after the 2 h pretreatment time previously reported in the empirically optimized synthetic procedure. The current limitations of this microscopy approach are also determined and discussed with respect to the addition of solid reagents during in operando imaging. Characterization of the resulting soluble fluorophore-tagged organozinc/LiCl complex by 1H NMR spectroscopy, mass spectrometry, and fluorescence spectroscopy provided insight into its solution dynamics and chemical exchange processes.« less

Course and Curriculum Improvement Materials: Mathematics, Science, Social Sciences - Elementary, Intermediate, Secondary.

ERIC Educational Resources Information Center

National Science Foundation, Washington, DC.

This is a list of curriculum improvement materials produced by major course and curriculum projects supported by the National Science Foundation's Division of Pre-College Education in Science. The materials are grouped by educational level (elementary, intermediate, and secondary) and within each level by broad discipline groupings (mathematics,…

Vertical Integration at Junior and Intermediate Levels. School Research Newsletter.

ERIC Educational Resources Information Center

Marklund, Inger, Ed.; Hanse, Mona-Britt, Ed.

1984-01-01

In recent years, there has been a rapid growth of interest in Sweden in vertically integrated classes in compulsory schools, especially at junior high school and intermediate grade levels. This development is supported in various ways by the curriculum, partly because it puts more emphasis than previous curricula on the occurrence of teaching…

Postural Control During Cascade Ball Juggling: Effects of Expertise and Base of Support.

PubMed

Rodrigues, Sérgio T; Polastri, Paula F; Gotardi, Gisele C; Aguiar, Stefane A; Mesaros, Marcelo R; Pestana, Mayara B; Barbieri, Fabio A

2016-08-01

Cascade ball juggling is a complex perceptual motor skill which requires efficient postural stabilization. The aim of this study was to investigate effects of experience (expert and intermediate groups) and foot distance (wide and narrow stances) on body sway of jugglers during three ball cascade juggling. A total of 10 expert jugglers and 11 intermediate jugglers participated in this study. Participants stood barefoot on the force plate (some participants wore a gaze tracking system), with feet maintained in wide and narrow conditions and performed three 40-seconds trials of the three-ball juggling task. Dependent variables were sway mean velocity, amplitude, mean frequency, number of ball cycles, fixation number, mean duration and its variability, and area of gaze displacement. Two-way analyses of variance with factors for group and condition were conducted. Experts' body sway was characterized by lower velocity and smaller amplitude as compared to intermediate group. Interestingly, the more challenging (narrow) basis of support caused significant attenuation in body sway only for the intermediate group. These data suggest that expertise in cascade juggling was associated with refined postural control. © The Author(s) 2016.

Influence of Abutment Angle on Implant Strain When Supporting a Distal Extension Removable Partial Dental Prosthesis: An In Vitro Study.

PubMed

Hirata, Kiyotaka; Takahashi, Toshihito; Tomita, Akiko; Gonda, Tomoya; Maeda, Yoshinobu

This study evaluated the impact of angled abutments on strain in implants supporting a distal extension removable partial denture. An in vitro model of an implant supporting a distal extension removable partial denture was developed. The implant was positioned with a 17- or 30-degree mesial inclination, with either a healing abutment or a corrective multiunit abutment. Levels of strain under load were compared, and the results were compared using t test (P = .05). Correcting angulation with a multiunit angled abutment significantly decreased strain (P < .05) when compared with a healing abutment. An angled abutment decreased the strain on an inclined implant significantly more than a healing abutment when loaded under a distal extension removable partial denture.

Implant support for removable partial overdentures: a case report.

PubMed

Halterman, S M; Rivers, J A; Keith, J D; Nelson, D R

1999-01-01

Functional stability and the preservation of remaining alveolar bone are primary, and often elusive, goals when restoring the partially edentulous arch. The incorporation of dental implants for the partial support of removable prostheses offers a practical adjunct in the fulfillment of these objectives. Planning for complex courses of treatment that include dental implants requires close coordination between the surgeon and the restorative dentist. Decisions that deal with type, location, size, number of implant fixtures, and design of the prosthesis are critical. All of these areas must be discussed and established as acceptable to the patient and each clinician before the initiation of treatment. In this report, we present a course of patient treatment in which a removable partial denture is supported by natural remaining teeth in conjunction with osseointegrated implants.

The relationship between nitrogen fixation and the production of HD from D2 by cell-free extracts of soya-bean nodule bacteroids

PubMed Central

Turner, G. L.; Bergersen, F. J.

1969-01-01

1. Cell-free extracts prepared from soya-bean nodule bacteroids produced HD from D2 in the presence of dithionite, an ATP-generating system and nitrogen. 2. Crude extracts of bacteroids or of Azotobacter vinelandii showed some background D2 exchange when any one of these was omitted. 3. Partial purification of bacteroid extracts diminished this background activity and gave increased D2 exchange and nitrogen fixation. 4. Although increasing pN2 stimulated both reactions, the apparent Km (N2) for nitrogen fixation was much higher than the apparent Km (N2) for D2 exchange when partially purified bacteroid extracts were used. 5. Carbon monoxide was a competitive inhibitor of nitrogen fixation by partially purified bacteroid extracts, but D2 exchange was inhibited in a non-competitive fashion. 6. These results are discussed in relation to the possible existence of enzyme-bound intermediates of nitrogen fixation. PMID:5353527

Electron-pair-production cross section in the tip region of the positron spectrum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sud, K.K.; Sharma, D.K.

1984-11-01

The radial integrals for electron-pair production in a point Coulomb potential have been expressed by Sud, Sharma, and Sud in terms of the matrix generalization of the GAMMA function. Two new partial differential equations in photon energy satisfied by the matrix GAMMA function are obtained. We have obtained, on integrating the partial differential equations, accurate radial integrals as a function of photon energy for the pair production by intermediate-energy photons. The cross section in the tip region of the spectrum are calculated for photons of energy 5.0 to 10.0 MeV for /sup 92/U. The new technique results in extensive savingmore » in computer time as the basic radial integrals in terms of the hypergeometric function F/sub 2/ are computed at one photon energy for each pair of partial waves. The results of our calculations are compared with plane-wave Born-approximation results and with the calculations of Dugne and of Deck, Moroi, and Alling.« less

Direct Determinations of the πNN Coupling Constants

NASA Astrophysics Data System (ADS)

Ericson, T. E. O.; Loiseau, B.

1998-11-01

A novel extrapolation method has been used to deduce directly the charged πN N coupling constant from backward np differential scattering cross sections. The extracted value, g2c = 14.52(0.26) is higher than the indirectly deduced values obtained in nucleon-nucleon energy-dependent partial-wave analyses. Our preliminary direct value from a reanalysis of the GMO sum-rule points to an intermediate value of g2c about 13.97(30).

High-Energy Faceted SnO₂-Coated TiO₂ Nanobelt Heterostructure for Near-Ambient Temperature-Responsive Ethanol Sensor.

PubMed

Chen, Guohui; Ji, Shaozheng; Li, Haidong; Kang, Xueliang; Chang, Sujie; Wang, Yana; Yu, Guangwei; Lu, Jianren; Claverie, Jerome; Sang, Yuanhua; Liu, Hong

2015-11-11

A SnO2 gas sensor was prepared by a two-step oxidation process whereby a Sn(II) precursor was partially oxidized by a hydrothermal process and the resulting Sn3O4 nanoplates were thermally oxidized to yield SnO2 nanoplates. The SnO2 sensor was selective and responsive toward ethanol at a temperature as low as 43 °C. This low sensing temperature stems from the rapid charge transport within SnO2 and from the presence of high-energy (001) facets available for oxygen chemisorption. SnO2/TiO2 nanobelt heterostructures were fabricated by a similar two-step process in which TiO2 nanobelts acted as support for the epitaxial growth of intermediate Sn3O4. At temperatures ranging from 43 to 276 °C, the response of these branched nanobelts is more than double the response of SnO2 for ethanol detection. Our observations demonstrate the potential of low-cost SnO2-based sensors with controlled morphology and reactive facets for detecting gases around room temperature.

K-Ar geochronology of the Survey Pass, Ambler River and Eastern Baird Mountains quadrangles, southwestern Brooks Range, Alaska

USGS Publications Warehouse

Turner, Donald L.; Forbes, R.B.; Mayfield, C.F.

1978-01-01

We report 76 previously unpublished K-Ar mineral ages from 47 metamorphic and igneous rocks in the southwestern Brooks Range. The pattern of radiometric ages is complex, reflecting the complex geologic history of this area. Local and regional radiometric evidence suggests that the southern Brooks Range schist belt has, at least in part, undergone a late Precambrian metamorphism and that the parent sedimentary and igneous rocks for the metamorphic rocks dated as late Precambrian are at least this old (Precambrian Z). This schist terrane experienced a major thermal event in mid-Cretaceous time, causing widespread resetting of nearly all K-Ar mica ages. A series of apparent ages intermediate between late Precambrian and mid-Cretaceous are interpreted as indicating varying amounts of partial argon loss from older rocks during the Cretaceous event. The schist belt is characterized by dominant metasediments and subordinate metabasites and metafelsites. Blueschists occur within the schist belt from the Chandalar quadrangle westward to the Baird Mountains quadrangle, but geologic evidence does not support the existence of a fossil subduction zone.

Management applicability of the intermediate disturbance hypothesis across Mongolian rangeland ecosystems.

PubMed

Sasaki, Takehiro; Okubo, Satoru; Okayasu, Tomoo; Jamsran, Undarmaa; Ohkuro, Toshiya; Takeuchi, Kazuhiko

2009-03-01

The current growing body of evidence for diversity-disturbance relationships suggests that the peaked pattern predicted by the intermediate disturbance hypothesis (IDH) may not be the rule. Even if ecologists could quantify the diversity-disturbance relationship consistent with the IDH, the applicability of the IDH to land management has rarely been addressed. We examined two hypotheses related to the generality and management applicability of the IDH to Mongolian rangeland ecosystems: that the diversity-disturbance relationship varies as a function of landscape condition and that some intermediate scales of grazing can play an important role in terms of sustainable rangeland management through a grazing gradient approach. We quantified the landscape condition of each ecological site using an ordination technique and determined two types of landscape conditions: relatively benign and harsh environmental conditions. At the ecological sites characterized by relatively benign environmental conditions, diversity-disturbance relationships were generally consistent with the IDH, and maximum diversity was observed at some intermediate distance from the source of the grazing gradient. In contrast, the IDH was not supported at most (but not all) sites characterized by relatively harsh environmental conditions. The intermediate levels of grazing were generally located below the ecological threshold representing the points or zones at which disturbance should be limited to prevent drastic changes in ecological conditions, suggesting that there is little "conundrum" with regard to intermediate disturbance in the studied systems in terms of land management. We suggest that the landscape condition is one of the primary factors that cause inconsistencies in diversity-disturbance relationships. The ecological threshold can extend its utility in rangeland management because it also has the compatibility with the maintenance of species diversity. This study thus suggests that some intermediate scales of grazing and ecological thresholds are mutually supportive tools for sustainable management of Mongolian rangelands.

METHOD AND MEANS FOR SUPPORTING REACTOR FUEL CONTAINERS IN AN ASSEMBLY

DOEpatents

Currier, E.L. Jr.; Nicklas, J.H.; Coombs, C.A.

1962-12-11

This patent relates to means for supporting fuelcontaining tubes in an assembly which include grid means at either end of the fuel element assembly antl improved grid means intermediate of the ends to provide support against lateral displacement. (AEC)

Transition-metal-substituted indium thiospinels as novel intermediate-band materials: prediction and understanding of their electronic properties.

PubMed

Palacios, P; Aguilera, I; Sánchez, K; Conesa, J C; Wahnón, P

2008-07-25

Results of density-functional calculations for indium thiospinel semiconductors substituted at octahedral sites with isolated transition metals (M=Ti,V) show an isolated partially filled narrow band containing three t2g-type states per M atom inside the usual semiconductor band gap. Thanks to this electronic structure feature, these materials will allow the absorption of photons with energy below the band gap, in addition to the normal light absorption of a semiconductor. To our knowledge, we demonstrate for the first time the formation of an isolated intermediate electronic band structure through M substitution at octahedral sites in a semiconductor, leading to an enhancement of the absorption coefficient in both infrared and visible ranges of the solar spectrum. This electronic structure feature could be applied for developing a new third-generation photovoltaic cell.

The Mechanism of Viral Replication. Structure of Replication Complexes of Encephalomyocarditis Virus

PubMed Central

Thach, Sigrid S.; Dobbertin, Darrell; Lawrence, Charles; Golini, Fred; Thach, Robert E.

1974-01-01

The structure of the purified replicative intermediate of encephalomyocarditis virus was determined by electron microscopy. Approximately 80% of the replicative intermediate complexes were characterized by a filament of double-stranded RNA of widely variable length, which had a “bush” of single-stranded RNA at one end. In many examples one or more additional single-stranded bushes were appended internally to the double-stranded RNA filament. These results support the view that before deproteinization, replicative intermediate contains little if any double-stranded RNA. Images PMID:4366773

WISEP J004701.06+680352.1: An Intermediate Surface Gravity, Dusty Brown Dwarf in the AB Dor Moving Group

DTIC Science & Technology

2015-02-01

reserved. WISEP J004701.06+680352.1: AN INTERMEDIATE SURFACE GRAVITY, DUSTY BROWN DWARF IN THE AB DOR MOVING GROUP John E. Gizis1,9, Katelyn N...pc. The three-dimensional space mo- tion identifies it as a member of the AB Dor Moving Group, an identification supported by our classification of...SUBTITLE WISEP J004701+680352.1: An Intermediate Surface Gravity, Dusty Brown Dwarf In The AB Dor Moving Group 5a. CONTRACT NUMBER 5b. GRANT NUMBER

A unified intermediate and mechanism for soot combustion on potassium-supported oxides

PubMed Central

Li, Qian; Wang, Xiao; Xin, Ying; Zhang, Zhaoliang; Zhang, Yexin; Hao, Ce; Meng, Ming; Zheng, Lirong; Zheng, Lei

2014-01-01

The soot combustion mechanism over potassium-supported oxides (MgO, CeO2 and ZrO2) was studied to clarify the active sites and discover unified reaction intermediates in this typical gas-solid-solid catalytic reaction. The catalytically active sites were identified as free K+ rather than K2CO3, which can activate gaseous oxygen. The active oxygen spills over to soot and forms a common intermediate, ketene, before it was further oxidized into the end product CO2. The existence of ketene species was confirmed by density functional theory (DFT) calculations. The oxygen spillover mechanism is proposed, which is explained as an electron transfer from soot to gaseous oxygen through the active K+ sites. The latter mechanism is confirmed for the first time since it was put forward in 1950, not only by ultraviolet photoelectron spectroscopy (UPS) results but also by semi-empirical theoretical calculations. PMID:24740213

Singlet-to-triplet intermediates and triplet exciton dynamics in pentacene thinfilms

NASA Astrophysics Data System (ADS)

Thorsmolle, Verner; Korber, Michael; Obergfell, Emanuel; Kuhlman, Thomas; Campbell, Ian; Crone, Brian; Taylor, Antoinette; Averitt, Richard; Demsar, Jure

Singlet-to-triplet fission in organic semiconductors is a spin-conserving multiexciton process in which one spin-zero singlet excitation is converted into two spin-one triplet excitations on an ultrafast timescale. Current scientific interest into this carrier multiplication process is largely driven by prospects of enhancing the efficiency in photovoltaic applications by generating two long-lived triplet excitons by one photon. The fission process is known to involve intermediate states, known as correlated triplet pairs, with an overall singlet character, before being interchanged into uncorrelated triplets. Here we use broadband femtosecond real-time spectroscopy to study the excited state dynamics in pentacene thin films, elucidating the fission process and the role of intermediate triplet states. VKT and AJT acknowledge support by the LDRD program at Los Alamos National Laboratory and the Department of Energy, Grant No. DE-FG02-04ER118. MK, MO and JD acknowledge support by the Alexander von Humboldt Foundation.

ECUT: Energy Conversion and Utilization Technologies program. Heterogeneous catalysis modeling program concept

NASA Technical Reports Server (NTRS)

Voecks, G. E.

1983-01-01

Insufficient theoretical definition of heterogeneous catalysts is the major difficulty confronting industrial suppliers who seek catalyst systems which are more active, selective, and stable than those currently available. In contrast, progress was made in tailoring homogeneous catalysts to specific reactions because more is known about the reaction intermediates promoted and/or stabilized by these catalysts during the course of reaction. However, modeling heterogeneous catalysts on a microscopic scale requires compiling and verifying complex information on reaction intermediates and pathways. This can be achieved by adapting homogeneous catalyzed reaction intermediate species, applying theoretical quantum chemistry and computer technology, and developing a better understanding of heterogeneous catalyst system environments. Research in microscopic reaction modeling is now at a stage where computer modeling, supported by physical experimental verification, could provide information about the dynamics of the reactions that will lead to designing supported catalysts with improved selectivity and stability.

Biomechanical considerations on tooth-implant supported fixed partial dentures

PubMed Central

Calvani, Pasquale; Hirayama, Hiroshi

2012-01-01

This article discusses the connection of teeth to implants, in order to restore partial edentulism. The main problem arising from this connection is tooth intrusion, which can occur in up to 7.3% of the cases. The justification of this complication is being attempted through the perspective of biomechanics of the involved anatomical structures, that is, the periodontal ligament and the bone, as well as that of the teeth- and implant-supported fixed partial dentures. PMID:23255882

Inorganic dual-layer microporous supported membranes

DOEpatents

Brinker, C. Jeffrey; Tsai, Chung-Yi; Lu, Yungfeng

2003-03-25

The present invention provides for a dual-layer inorganic microporous membrane capable of molecular sieving, and methods for production of the membranes. The inorganic microporous supported membrane includes a porous substrate which supports a first inorganic porous membrane having an average pore size of less than about 25 .ANG. and a second inorganic porous membrane coating the first inorganic membrane having an average pore size of less than about 6 .ANG.. The dual-layered membrane is produced by contacting the porous substrate with a surfactant-template polymeric sol, resulting in a surfactant sol coated membrane support. The surfactant sol coated membrane support is dried, producing a surfactant-templated polymer-coated substrate which is calcined to produce an intermediate layer surfactant-templated membrane. The intermediate layer surfactant-templated membrane is then contacted with a second polymeric sol producing a polymeric sol coated substrate which is dried producing an inorganic polymeric coated substrate. The inorganic polymeric coated substrate is then calcined producing an inorganic dual-layered microporous supported membrane in accordance with the present invention.

Clinical experiences of implant-supported prostheses with laser-welded titanium frameworks in the partially edentulous jaw: a 5-year follow-up study.

PubMed

Ortorp, A; Jemt, T

1999-01-01

Titanium frameworks have been used in the endentulous implant patient for the last 10 years. However, knowledge of titanium frameworks for the partially dentate patient is limited. To report the 5-year clinical performance of implant-supported prostheses with laser-welded titanium frameworks in the partially edentulous jaw. A consecutive group of 383 partially edentulous patients were, on a routine basis, provided with fixed partial prostheses supported by Brånemark implants in the mandible or maxilla. Besides conventional frameworks in cast gold alloy, 58 patients were provided with titanium frameworks with three different veneering techniques, and clinical and radiographic 5-year data were collected for this group. The overall cumulative survival rate was 95.6% for titanium-framework prostheses and 93.6% for implants. Average bone loss during the follow-up period was 0.4 mm. The most common complications were minor veneering fractures. Loose and fractured implant screw components were fewer than 2%. An observation was that patients on medications for cardiovascular problems may lose more implants than others (p < .05). The clinical performance of prostheses with implant-supported laser-welded titanium frameworks was similar to that reported for conventional cast frames in partially edentulous jaws. Low-fusing porcelain veneers also showed clinical performance comparable to that reported for conventional porcelain-fused-to-metal techniques.

Tagging partially reconstructed objects with jet substructure

DOE PAGES

Freytsis, Marat; Volansky, Tomer; Walsh, Jonathan R.

2016-08-24

Here, we present a new tagger which aims at identifying partially reconstructed objects, in which only some of the constituents are collected in a single jet. As an example, we also focus on top decays in which either part of the hadronically decaying W or the b jet is soft or falls outside of the top jet cone. Furthermore, we construct an observable to identify remnant substructure from the decay and employ aggressive jet grooming to reject QCD backgrounds. The tagger is complementary to existing ones and works well in the intermediate boost regime where jet substructure techniques usually fail.more » It is anticipated that a similar tagger can be used to identify non-QCD hadronic jets, such as those expected from hidden valleys.« less

Geometrical and wave optics of paraxial beams.

PubMed

Meron, M; Viccaro, P J; Lin, B

1999-06-01

Most calculational techniques used to evaluate beam propagation are geared towards either fully coherent or fully incoherent beams. The intermediate partial-coherence regime, while in principle known for a long time, has received comparably little attention so far. The resulting shortage of adequate calculational techniques is currently being felt in the realm of x-ray optics where, with the advent of third generation synchrotron light sources, partially coherent beams become increasingly common. The purpose of this paper is to present a calculational approach which, utilizing a "variance matrix" representation of paraxial beams, allows for a straightforward evaluation of wave propagation through an optical system. Being capable of dealing with an arbitrary degree of coherence, this approach covers the whole range from wave to ray optics, in a seamless fashion.

Disease management programs in type 2 diabetes: quality of care.

PubMed

Berthold, Heiner K; Bestehorn, Kurt P; Jannowitz, Christina; Krone, Wilhelm; Gouni-Berthold, Ioanna

2011-06-01

To determine whether disease management programs (DMPs) for type 2 diabetes mellitus (T2DM) can improve some processes of care and intermediate outcomes. Two cross-sectional registries of patients with T2DM were used for data extraction before (previous cohort) and after (recent cohort) introduction of DMPs in Germany (N = 78,110). In the recent cohort, 15,293 patients were treated within the DMPs and 9791 were not. Processes of care, medications, and intermediate outcomes (achievement of treatment targets for low-density lipoprotein [LDL] cholesterol, blood pressure, and glycosylated hemoglobin [A1C]) were analyzed using multi- variable, multilevel logistic regression, adjusting for patient case-mix and physician-level clustering to derive odds ratios and 95% confidence intervals (CIs). Availability of structured diabetes education and of lipid, blood pressure, and A1C measurements increased over time. In DMP patients, availability was significantly higher for blood pressure and A1C but not for lipid measurements. Prescription of angiotensin-converting enzyme inhibitors, oral antidiabetic drugs, and insulin increased over time and was more common in DMP patients. Statin prescription increased over time but was not influenced by DMP status. Intermediate outcomes improved over time, but DMPs had no influence on intermediate outcomes except for reaching LDL cholesterol targets (odds ratio 1.12 [95% CI 1.06, 1.19] in favor of DMPs). While there may be some unmeasured confounding, our data suggest that improvement in processes of care by DMPs, as implemented in Germany, only partially translates into improvement of intermediate outcomes.

Crystallization Temperatures of Lower Crustal Gabbros from the Oman Ophiolite and the Persistence of the 'Mush Zone' at Intermediate/Fast Spreading Ridges

NASA Astrophysics Data System (ADS)

VanTongeren, J. A.

2017-12-01

Oceanic crust is formed when mantle-derived magmas are emplaced at the ridge axis, a zone of intense rifting and extension. Magmas begin to cool and crystallize on-axis, forming what is termed the "Mush Zone", a region of partially molten rocks. Several attempts have been made to understand the nature of the Mush Zone at fast spreading mid-ocean ridges, specifically how much partial melt exists and how far off-axis the Mush Zone extends. Geophysical estimates of P-wave velocity perturbations at the East Pacific Rise show a region of low velocity approximately 1.5-2.5 km off-axis, which can be interpreted to be the result of higher temperature [e.g. Dunn et al., 2000, JGR] or the existence of partial melt. New petrological and geochemical data and methods allow for the calculation of the lateral extent of the Mush Zone in the lower oceanic crust on exposed sections collected from the Oman ophiolite, a paleo-fast/intermediate spreading center. I will present new data quantifying the crystallization temperatures of gabbros from the Wadi Khafifah section of lower oceanic gabbros from the Oman ophiolite. Crystallization temperatures are calculated with the newly developed plagioclase-pyroxene REE thermometer of Sun and Liang [2017, Contrib. Min. Pet.]. There does not appear to be any systematic change in the crystallization temperature of lower crustal gabbros with depth in the crust. In order to quantify the duration of crystallization and the lateral extent of the Mush Zone of the lower crust, crystallization temperatures are paired with estimates of the solidus temperature and cooling rate determined from the same sample, previously constrained by the Ca diffusion in olivine geothermometer/ geospeedometer [e.g. VanTongeren et al., 2008 EPSL]. There is no systematic variation in the closure temperature of Ca in olivine, or the cooling rate to the 800°C isotherm. These results show that gabbros throughout the lower crust of the Oman ophiolite remain in a partially molten state for an average of 10,000 years. Assuming a paleo-spreading rate similar to that of the East Pacific Rise, this translates to a "Mush Zone" of partially molten rock up to 1 km off-axis, slightly less than the low velocity zone observed geophysically on the East Pacific Rise.

An impurity intermediate band due to Pb doping induced promising thermoelectric performance of Ca5In2Sb6.

PubMed

Feng, Zhenzhen; Wang, Yuanxu; Yan, Yuli; Zhang, Guangbiao; Yang, Jueming; Zhang, Jihua; Wang, Chao

2015-06-21

Band engineering is one of the effective approaches for designing ideal thermoelectric materials. Introducing an intermediate band in the band gap of semiconducting thermoelectric compounds may largely increase the carrier concentration and improve the electrical conductivity of these compounds. We test this hypothesis by Pb doping in Zintl Ca5In2Sb6. In the current work, we have systematically investigated the electronic structure and thermoelectric performances of substitutional doping with Pb on In sites at a doping level of 5% (0.2 e per cell) for Ca5In2Sb6 by using density functional theory combined with semi-classical Boltzmann theory. It is found that in contrast to Zn doping, Pb doping introduces a partially filled intermediate band in the band gap of Ca5In2Sb6, which originates from the Pb s states by weakly hybridizing with the Sb p states. Such an intermediate band dramatically increases the electrical conductivity of Ca5In2Sb6 and has little detrimental effect on its Seebeck coefficient, which may increase its thermoelectric figure of merit, ZT. Interestingly, a maximum ZT value of 2.46 may be achieved at 900 K for crystalline Pb-doped Ca5In2Sb6 when the carrier concentration is optimized. Therefore, Pb-doped Ca5In2Sb6 may be a promising thermoelectric material.

Treatment planning: implant-supported partial overdentures.

PubMed

Chee, Winston W L

2005-04-01

When multiple anterior teeth are missing, many options of replacement are available. Traditionally, the choice was between a fixed or removable prostheses. Today, with the predictability of dental implants, the options of tooth replacement range from removable partial dentures to implant-supported fixed prostheses. The choice of which restoration that will best provide occlusion and esthetics depends on multiple factors including the number and location of missing teeth, the residual ridge form in relation to the replacement teeth, the relationship of the maxillary and mandibular anterior teeth, the condition of teeth adjacent to the edentulous span, the amount of bone available for implant placement, the patients "smile line" and display of teeth, lip support, and financial constraints. When there is minimal loss of the ridge contour, restorations that emerge from the ridge are the most functional and esthetic restorations, adhesive-type fixed partial dentures, conventional fixed partial dentures, and implant-supported restorations can be indicated with the choice of restoration dependent on a risk benefit and cost benefit analysis. When there is a loss of ridge contour due to residual ridge resorption or trauma, the decision becomes more complex as not only does the tooth structure need to be replaced, the ridge form also has to be replaced. (Figures 1 and 2). This can be assessed clinically as illustrated by Figures 1 and 2 where a dis crepancy in arch form and ridge form in relation to the adjacent teeth and/or opposing arch can be observed. Other considerations are lip support and display of the teeth when smiling. This article presents a case and rationale for implant-supported par tial overdentures. Many authors have written on the merits of com plete overdentures. The complete overdenture has proven to be an improvement over conventional complete prostheses with respect to chewing efficiency, patient comfort and satisfaction. In partial edentulism, the implant-supported overdenture has several advantages, some in common with a removable partial denture.

Medical Comorbidity of Full and Partial Posttraumatic Stress Disorder in United States Adults: Results from Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions

PubMed Central

Pietrzak, Robert H.; Goldstein, Risë B.; Southwick, Steven M.; Grant, Bridget F.

2011-01-01

Objective This study examined associations between lifetime trauma exposures, PTSD and partial PTSD, and past-year medical conditions in a nationally representative sample of U.S. adults. Methods Face-to-face interviews were conducted with 34,653 participants in the Wave 2 National Epidemiologic Survey on Alcohol and Related Conditions. Logistic regression analyses evaluated associations of trauma exposure, PTSD and partial PTSD with respondent-reported medical diagnoses. Results After adjustment for sociodemographic characteristics and comorbid Axis I and II disorders, respondents with full PTSD were more likely than traumatized respondents without full or partial PTSD (comparison group) to report diagnoses of diabetes mellitus, noncirrhotic liver disease, angina pectoris, tachycardia, hypercholesterolemia, other heart disease, stomach ulcer, HIV seropositivity, gastritis, and arthritis (odds ratios [ORs]=1.2-2.5). Respondents with partial PTSD were more likely than the comparison group to report past-year diagnoses of stomach ulcer, angina pectoris, tachycardia, and arthritis (ORs=1.3-1.6). Men with full and partial PTSD were more likely than controls to report diagnoses of hypertension (both ORs=1.6), and both men and women with PTSD (ORs=1.8 and 1.6, respectively), and men with partial PTSD (OR=2.0) were more likely to report gastritis. Total number of lifetime traumatic event types was associated with many assessed medical conditions (ORs=1.04-1.16), reducing the magnitudes and rendering non-significant some of the associations between PTSD status and medical conditions. Conclusions Greater lifetime trauma exposure and PTSD are associated with numerous medical conditions, many of which are stress-related and chronic, in U.S. adults. Partial PTSD is associated with intermediate odds of some of these conditions. PMID:21949429

The role of single immediate loading implant in long Class IV Kennedy mandibular partial denture.

PubMed

Mohamed, Gehan F; El Sawy, Amal A

2012-10-01

The treatment of long-span Kennedy class IV considers a prosthodontic challenge. This study evaluated the integrity of principle abutments in long Kennedy class IV clinically and radiographically, when rehabilitated with conventional metallic partial denture as a control group and mandibular partial overdentures supported with single immediately loaded implant in symphyseal as a study group. Twelve male patients were divided randomly allotted into two equal groups. First group patients received removable metallic partial denture, whereas in the second group, patients received partial overdentures supported with single immediately loaded implant in symphyseal region. The partial dentures design in both groups was the same. Long-cone paralleling technique and transmission densitometer were used at the time of denture insertion, 3, 6, and 12 months. Gingival index, bone loss, and optical density were measured for principle abutments during the follow-up. A significant reduction in bone loss and density were detected in group II comparing with group I. Gingival index had no significant change (p-value < 0.05). A single symphyseal implant in long span class IV Kennedy can play a pivotal role to improve the integrity of the principle abutments and alveolar bone support. © 2010 Wiley Periodicals, Inc.

Cobalt spin states and hyperfine interactions in LaCoO3 investigated by LDA+U calculations

NASA Astrophysics Data System (ADS)

Leighton, C.; Hsu, H.; Blaha, P.; Wentzcovitch, R. M.

2010-12-01

The spin states of cobalt ions in the bulk and epitaxial-thin-film lanthanum cobaltite (LaCoO3) have been controversial for years. The controversial point is mainly the presence of intermediate-spin (IS) Co in the temperature range of 0-85 K. In this region, bulk LaCoO3 experiences a crossover from a diamagnetic to a paramagnetic phase, and the thin-film LaCoO3 is ferromagnetic and insulator. An approach to probe the Co spin state is thus of interest. With a series of LDA+U calculations, we have demonstrated that the electric field gradient (EFG) at the Co nucleus can be used as a fingerprint to identify the spin state of the Co ion in each case. Therefore, in principle, the spin state of the Co ion can be unambiguously determined from nuclear magnetic resonance (NMR) spectra. Our calculations also suggest that the presence of IS Co in this temperature range is unlikely, based not only on its relatively higher energy, but also on its associated conducting band structure incompatible with the measured insulating conductivity. This work was primarily supported by the MRSEC Program of NSF under Awards Number DMR-0212302 and DMR-0819885, and partially supported by NSF under ATM-0428774 (V-Lab), EAR-1019853, and EAR-0810272. The computations were performed mainly at the Minnesota Supercomputing Institute (MSI).

Attitudes toward the large-scale implementation of an incident reporting system.

PubMed

Braithwaite, Jeffrey; Westbrook, Mary; Travaglia, Joanne

2008-06-01

An electronic Incident Information Management System implemented system-wide by the Department of Health, New South Wales, Australia was evaluated. We hypothesized that health professionals (i) would support the system via utilization and favourable attitudes and (ii) that their usage and attitudes would vary according to profession with nurses being most, and doctors least, favourably disposed. An online, anonymous questionnaire survey of 2185 health practitioners. Undertaking system training, satisfaction with training, reporting incidents, incident reporting rates since system introduction and attitude questions focusing on use, security and evaluation of the system and workplace safety cultures. The first hypothesis received partial support. The majority of respondents had undertaken training and rated it highly. Most had reported incidents and maintained their previous reporting levels. Most attitudes regarding using the system and its security were favourable. Mixed attitudes were held about workplace safety cultures and the value of the system. Deficiencies in quality of reporting, feedback on incident reports and resources to analyse incident data were problems identified. The second hypothesis was confirmed. Nurses were most, and doctors least, likely to undertake training, report incidents and express favourable attitudes. Allied health responses were intermediate to those of the other professions. The system implementation was relatively successful, but more so with some professions. Problems identified indicated that expectations as to the goals achievable in the short term were optimistic, but these are amenable to planned interventions.

ICASE Semiannual Report. April 1, 1993 through September 30, 1993

DTIC Science & Technology

1993-12-01

scientists from universities and industry who have resident appointments for limited periods of time as well as by visiting and resident consultants... time integration. One of these is the time advancement of systems of hyperbolic partial differential equations via high order Runge- Kutta algorithms...Typically if the R-K methods is of, say, fourth order accuracy then there will be four intermediate steps between time level t = n6 and t + 6 = (n + 1)b

Nitrolysis of the CN Single Bond and Related Chemistry of Nitro and Nitroso Groups

DTIC Science & Technology

1985-02-01

nitrosonium cation, eq (1). 3 An alternative source of the iminium cation intermediate was proposed for the very poor conversions of tertiary aliphatic...the molecular ion I + at 228 (100%) and contained no evidence for the presence of contamination with partial deuter- ation products with masses 222...expected property of R-salt. Lewis acids also were found to be reac- tive. Both nitrosonium and nitronium tetrafluoroborate con- verted R-salt to the oxide

Process for the deposition of high temperature stress and oxidation resistant coatings on silicon-based substrates

DOEpatents

Sarin, V.K.

1991-07-30

A process is disclosed for depositing a high temperature stress and oxidation resistant coating on a silicon nitride- or silicon carbide-based substrate body. A gas mixture is passed over the substrate at about 900--1500 C and about 1 torr to about ambient pressure. The gas mixture includes one or more halide vapors with other suitable reactant gases. The partial pressure ratios, flow rates, and process times are sufficient to deposit a continuous, fully dense, adherent coating. The halide and other reactant gases are gradually varied during deposition so that the coating is a graded coating of at least two layers. Each layer is a graded layer changing in composition from the material over which it is deposited to the material of the layer and further to the material, if any, deposited thereon, so that no clearly defined compositional interfaces exist. The gases and their partial pressures are varied according to a predetermined time schedule and the halide and other reactant gases are selected so that the layers include (a) an adherent, continuous intermediate layer about 0.5-20 microns thick of an aluminum nitride or an aluminum oxynitride material, over and chemically bonded to the substrate body, and (b) an adherent, continuous first outer layer about 0.5-900 microns thick including an oxide of aluminum or zirconium over and chemically bonded to the intermediate layer.

Process for the deposition of high temperature stress and oxidation resistant coatings on silicon-based substrates

DOEpatents

Sarin, Vinod K.

1991-01-01

A process for depositing a high temperature stress and oxidation resistant coating on a silicon nitride- or silicon carbide-based substrate body. A gas mixture is passed over the substrate at about 900.degree.-1500.degree. C. and about 1 torr to about ambient pressure. The gas mixture includes one or more halide vapors with other suitable reactant gases. The partial pressure ratios, flow rates, and process times are sufficient to deposit a continuous, fully dense, adherent coating. The halide and other reactant gases are gradually varied during deposition so that the coating is a graded coating of at least two layers. Each layer is a graded layer changing in composition from the material over which it is deposited to the material of the layer and further to the material, if any, deposited thereon, so that no clearly defined compositional interfaces exist. The gases and their partial pressures are varied according to a predetermined time schedule and the halide and other reactant gases are selected so that the layers include (a) an adherent, continuous intermediate layer about 0.5-20 microns thick of an aluminum nitride or an aluminum oxynitride material, over and chemically bonded to the substrate body, and (b) an adherent, continuous first outer layer about 0.5-900 microns thick including an oxide of aluminum or zirconium over and chemically bonded to the intermediate layer.

Decoding Structural Properties of a Partially Unfolded Protein Substrate: En Route to Chaperone Binding

PubMed Central

Nagpal, Suhani; Tiwari, Satyam; Mapa, Koyeli; Thukral, Lipi

2015-01-01

Many proteins comprising of complex topologies require molecular chaperones to achieve their unique three-dimensional folded structure. The E.coli chaperone, GroEL binds with a large number of unfolded and partially folded proteins, to facilitate proper folding and prevent misfolding and aggregation. Although the major structural components of GroEL are well defined, scaffolds of the non-native substrates that determine chaperone-mediated folding have been difficult to recognize. Here we performed all-atomistic and replica-exchange molecular dynamics simulations to dissect non-native ensemble of an obligate GroEL folder, DapA. Thermodynamics analyses of unfolding simulations revealed populated intermediates with distinct structural characteristics. We found that surface exposed hydrophobic patches are significantly increased, primarily contributed from native and non-native β-sheet elements. We validate the structural properties of these conformers using experimental data, including circular dichroism (CD), 1-anilinonaphthalene-8-sulfonic acid (ANS) binding measurements and previously reported hydrogen-deutrium exchange coupled to mass spectrometry (HDX-MS). Further, we constructed network graphs to elucidate long-range intra-protein connectivity of native and intermediate topologies, demonstrating regions that serve as central “hubs”. Overall, our results implicate that genomic variations (or mutations) in the distinct regions of protein structures might disrupt these topological signatures disabling chaperone-mediated folding, leading to formation of aggregates. PMID:26394388

Intermediate-energy inverse-kinematics one-proton pickup reactions on neutron-deficient fp-shell nuclei

NASA Astrophysics Data System (ADS)

McDaniel, S.; Gade, A.; Tostevin, J. A.; Baugher, T.; Bazin, D.; Brown, B. A.; Cook, J. M.; Glasmacher, T.; Grinyer, G. F.; Ratkiewicz, A.; Weisshaar, D.

2012-01-01

Background: Thick-target-induced nucleon-adding transfer reactions onto energetic rare-isotope beams are an emerging spectroscopic tool. Their sensitivity to single-particle structure complements one-nucleon removal reaction capabilities in the quest to reveal the evolution of nuclear shell structure in very exotic nuclei. Purpose: Our purpose is to add intermediate-energy, carbon-target-induced one-proton pickup reactions to the arsenal of γ-ray-tagged direct reactions applicable in the regime of low beam intensities and to apply these for the first time to fp-shell nuclei. Methods: Inclusive and partial cross sections were measured for the 12C(48Cr,49Mn+γ)X and 12C(50Fe,51Co+γ)X proton pickup reactions at 56.7 and 61.2 MeV/nucleon, respectively, using coincident particle-γ spectroscopy at the National Superconducting Cyclotron Laboratory. The results are compared to reaction theory calculations using fp-shell-model nuclear structure input. For comparison with our previous work, the same reactions were measured on 9Be targets. Results: The measured partial cross sections confirm the specific population pattern predicted by theory, with pickup into high-ℓ orbitals being strongly favored, driven by linear and angular momentum matching. Conclusion: Carbon-target-induced pickup reactions are well suited, in the regime of modest beam intensity, to study the evolution of nuclear structure, with specific sensitivities that are well described by theory.

Prolonged partial cardiopulmonary bypass in rats.

PubMed

Alexander, B; Al Ani, H R

1983-07-01

Membrane oxygenators have been shown to be atraumatic during cardiopulmonary bypass. A novel design for a membrane tubing oxygenator originated in this laboratory was used for prolonged partial supportive cardiopulmonary bypass in lambs and displayed excellent biocompatability characteristics. This was miniaturized, to result in a prime volume of 12 ml, in order to investigate the feasibility of prolonged partial supportive cardiopulmonary bypass in rats. The performance of this miniaturized circuit over perfusion periods up to 6 hr is described, with particular reference to hematological changes.

Restoration of unfavorably positioned implants for a partially endentulous patient by using an overdenture retained with a milled bar and attachments: a clinical report.

PubMed

Asvanund, Chanavut; Morgano, Steven M

2004-01-01

The restorative dentist may encounter patients with previously placed misaligned implants that are well integrated. Often, these patients have deficient alveolar ridge contour further complicating treatment options. This clinical report describes a treatment approach for a partially edentulous patient with unfavorably positioned implants that incorporated: (1) an implant-supported milled bar with a removable, metal-acrylic resin, partial overdenture, (2) implant-supported single crowns, and (3) crowns retained by natural teeth.

Motor planning flexibly optimizes performance under uncertainty about task goals.

PubMed

Wong, Aaron L; Haith, Adrian M

2017-03-03

In an environment full of potential goals, how does the brain determine which movement to execute? Existing theories posit that the motor system prepares for all potential goals by generating several motor plans in parallel. One major line of evidence for such theories is that presenting two competing goals often results in a movement intermediate between them. These intermediate movements are thought to reflect an unintentional averaging of the competing plans. However, normative theories suggest instead that intermediate movements might actually be deliberate, generated because they improve task performance over a random guessing strategy. To test this hypothesis, we vary the benefit of making an intermediate movement by changing movement speed. We find that participants generate intermediate movements only at (slower) speeds where they measurably improve performance. Our findings support the normative view that the motor system selects only a single, flexible motor plan, optimized for uncertain goals.

User's guide to computer program CIVM-JET 4B to calculate the transient structural responses of partial and/or complete structural rings to engine-rotor-fragment impact

NASA Technical Reports Server (NTRS)

Stagliano, T. R.; Spilker, R. L.; Witmer, E. A.

1976-01-01

A user-oriented computer program CIVM-JET 4B is described to predict the large-deflection elastic-plastic structural responses of fragment impacted single-layer: (a) partial-ring fragment containment or deflector structure or (b) complete-ring fragment containment structure. These two types of structures may be either free or supported in various ways. Supports accommodated include: (1) point supports such as pinned-fixed, ideally-clamped, or supported by a structural branch simulating mounting-bracket structure and (2) elastic foundation support distributed over selected regions of the structure. The initial geometry of each partial or complete ring may be circular or arbitrarily curved; uniform or variable thicknesses of the structure are accommodated. The structural material is assumed to be initially isotropic; strain hardening and strain rate effects are taken into account.

Organometallics in High Energy Chemistry.

DTIC Science & Technology

1983-10-31

Luines Physeical ftaenc Chemistry DepatneWu. SJI International. Menlo PWr *. CaiOwrnia M10 Rceived Nouvber 8. 1IM The otslytic formation of6nw carbon...support the idea that the metalloazocyclopropane intermediate is the reactive intermediate that leads to transalkylation. A discussion of the...exceptionally good correlation between the catalytic reactivity patterns of palladium black in its reactions with tertiary amines and those of homogeneous

Development of Anode-Supported Single Cells and Small Stacks for Intermediate Temperature Sofc at Kepri

NASA Astrophysics Data System (ADS)

Yoo, Y.-S.; Park, J.-W.; Park, J.-K.; Lim, H.-C.; Oh, J.-M.; Bae, J.-M.

Recent results on intermediate temperature-operating solid oxide fuel cells (IT-SOFC) are mainly focused on getting the higher performance of single cell at lower operating temperature, especially using planar type. We have started a project to develop 1 kW-class SOFC system for Residential Power Generation(RPG) application. For a 1 kW-class SOFC stack that can be operated at intermediate temperatures, we have developed anode-supported, planar type SOFC to have advantages for commercialization of SOFCs considering mass production and using cost-effective interconnects such as ferritic stainless steels. At higher temperature, performance of SOFC can be increased due to higher electrochemical activity of electrodes and lower ohmic losses, but the surface of metallic interconnects at cathode side is rapidly oxidized into resistive oxide scale. For efficient operation of SOFC at reduced temperature at, firstly we have developed alternative cathode materials of LSCF instead of LSM to get higher performance of electrodes, and secondly introduced functional-layered structure at anode side. The I-V and AC impedance characteristics of improved single cells and small stacks were evaluated at intermediate temperatures (650°C and 750°C) using hydrogen gas as a fuel.

Research in Applied Mathematics Related to Nonlinear System Theory.

DTIC Science & Technology

1985-08-01

This list includes A. OZGULER, P. KHARGONEKAR, J. RIBERA , and T. GEORGIOU. Also supported was the Principal Investigator (partial summer support only...regulator problem with internal stability", Ph.D. dissertation, University of Florida, 63 pages. J. RIBERA [1982] "Identification of linear relations... Ribera , doctoral student (now on faculty of I. E. S. E., Barcelona, SPAIN) Dr. A. Tannenbaum, Visiting Professor (partial summer support only, now

Overcoming difficulties with equipoise to enable recruitment to a randomised controlled trial of partial ablation versus radical prostatectomy for unilateral localised prostate cancer.

PubMed

Elliott, Daisy; Hamdy, Freddie C; Leslie, Tom A; Rosario, Derek; Dudderidge, Tim; Hindley, Richard; Emberton, Mark; Brewster, Simon; Sooriakumaran, Prasanna; Catto, James W F; Emara, Amr; Ahmed, Hashim; Whybrow, Paul; le Conte, Steffi; Donovan, Jenny L

2018-06-11

To describe how clinicians conceptualised equipoise in the PART (Partial prostate Ablation versus Radical prosTatectomy in intermediate risk, unilateral clinically localised prostate cancer) feasibility study and how this affected recruitment. PART included a QuinteT Recruitment Intervention (QRI) to optimise recruitment. Phase I aimed to understand recruitment, and included scrutinising recruitment data, interviewing the Trial Management Group and recruiters (n=13), and audio-recording recruitment consultations (n=64). Data were analysed using qualitative content and thematic analysis methods. In Phase II, strategies to improve recruitment were developed and delivered. Initially many recruiters found it difficult to maintain a position of equipoise and held preconceptions about which treatment was best for particular patients. They did not feel comfortable about approaching all eligible patients, and when the study was discussed, biases were conveyed through the use of terminology, poorly balanced information and direct treatment recommendations. Individual and group feedback led to presentations to patients becoming clearer and enabled recruiters to reconsider their sense of equipoise. Although the precise impact of the QRI alone cannot be determined, recruitment increased (from mean 1.4 (range=0-4) to 4.5 (range=0-12) patients per month) and the feasibility study reached its recruitment target. Although clinicians find it challenging to recruit participants to a trial comparing different contemporary treatments for prostate cancer, training and support can enable recruiters to become more comfortable with conveying equipoise and providing clearer information to patients. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Photosynthesis and growth response of almond to increased atmospheric ozone partial pressures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Retzlaff, W.A.; Williams, L.E.; DeJong, T.M.

Uniform nursery stock of five almond cultivars [Prunus dulcis (Mill) D.A. Webb syn. P. amygdalus Batsch, cv. Butte, Carmel, Mission, Nonpareil, and Sonora] propagated on peach (P. domstica L. Batsch.) rootstock were exposed to three different atmospheric ozone (O[sub 3]) partial pressures. The trees were planted in open-top fumigation chambers on 19 Apr. 1989 at the University of California Kearny Agricultural Center located in the San Joaquin Valley of California. Exposures of the trees to three atmospheric O[sub 3] partial pressures lasted from 1 June to 2 Nov. 1989. The mean 12-h [0800-2000 h Pacific Daylight Time (PDT)] O[sub 3]more » partial pressures measured in the open-top chambers during the experimental period were 0.038, 0.060, and 0.112 [mu]Pa Pa[sup [minus]1] O[sub 3] in the charcoal filtered, ambient, and ambient + O[sub 3] treatments, respectively. Leaf net CO[sub 2] assimilation, trunk cross-sectional area growth, and root, trunk, foliage, and total dry weight of Nonpareil were reduced by increased atmospheric O[sub 3] partial pressures. Mission was unaffected by O[sub 3] and Butte, Carmel, and Sonora were intermediate in their responses. Foliage of Nonpareil also abscised prematurely in the ambient and ambient + O[sub 3] treatments. The results indicate that there are almond cultivars that are sensitive to O[sub 3] exposure.« less

Experimental and geochemical evidence for derivation of the El Capitan Granite, California, by partial melting of hydrous gabbroic lower crust

USGS Publications Warehouse

Ratajeski, K.; Sisson, T.W.; Glazner, A.F.

2005-01-01

Partial melting of mafic intrusions recently emplaced into the lower crust can produce voluminous silicic magmas with isotopic ratios similar to their mafic sources. Low-temperature (825 and 850??C) partial melts synthesized at 700 MPa in biotite-hornblende gabbros from the central Sierra Nevada batholith (Sisson et al. in Contrib Mineral Petrol 148:635-661, 2005) have major-element and modeled trace-element (REE, Rb, Ba, Sr, Th, U) compositions matching those of the Cretaceous El Capitan Granite, a prominent granite and silicic granodiorite pluton in the central part of the Sierra Nevada batholith (Yosemite, CA, USA) locally mingled with coeval, isotopically similar quartz diorite through gabbro intrusions (Ratajeski et al. in Geol Soc Am Bull 113:1486-1502, 2001). These results are evidence that the El Capitan Granite, and perhaps similar intrusions in the Sierra Nevada batholith with lithospheric-mantle-like isotopic values, were extracted from LILE-enriched, hydrous (hornblende-bearing) gabbroic rocks in the Sierran lower crust. Granitic partial melts derived by this process may also be silicic end members for mixing events leading to large-volume intermediate composition Sierran plutons such as the Cretaceous Lamarck Granodiorite. Voluminous gabbroic residues of partial melting may be lost to the mantle by their conversion to garnet-pyroxene assemblages during batholithic magmatic crustal thickening. ?? Springer-Verlag 2005.

H2O2/TiO2 photocatalytic oxidation of metol. Identification of intermediates and reaction pathways.

PubMed

Aceituno, Mónica; Stalikas, Constantine D; Lunar, Loreto; Rubio, Soledad; Pérez-Bendito, Dolores

2002-08-01

The applicability of H2O2 to increase the efficiency of TiO2 photocatalytic degradations was investigated. The photographic developer metol [N-methyl-p-aminophenol] that does not adsorb on the surface of TiO2 particulates was used as a model for this purpose. It was proved that metol was mineralised under oxidation with H2O2/TiO2/UV through different thermal and photochemical reactions. Identification of intermediates by both HPLC-electron impact-MS and HPLC-electrospray ionisation-MS helped to elucidate the role of H2O2 and TiO2 in the degradation process and to establish degradation pathways. Intermediates yielded were partially oxygenated aromatic species and dimers, which were amenable to oxidation. The optimal degradation conditions found for mineralisation were 0.4 M H2O2, 5 mg/ml TiO2, pH 9 and irradiation centred at 360 nm (4.9 mW/cm2). The use of oxidants opens an interesting medium to the treatment of effluents containing a diversity of organics since they increase substantially the efficiency of TiO2 photocatalytic degradations.

The high content of β-carotene present in orange-pulp fruits of Carica papaya L. is not correlated with a high expression of the CpLCY-β2 gene.

PubMed

Chan-León, Arianna C; Estrella-Maldonado, Humberto; Dubé, Pascal; Fuentes Ortiz, Gabriela; Espadas-Gil, Francisco; Talavera May, Carlos; Ramírez Prado, Jorge; Desjardins, Yves; Santamaría, Jorge M

2017-10-01

We investigated the transcriptional regulation of six genes involved in carotenoid biosynthesis, together with the carotenoid accumulation during postharvest ripening of three different papaya genotypes of contrasting pulp color. Red-pulp genotype (RPG) showed the lowest content of yellow pigments (YP), such as β-cryptoxanthin, zeaxanthin, and violaxanthin, together with the lowest relative expression levels (REL) of CpLCY-β2 and CpCHX-β genes. On the contrary, the yellow-pulp genotype (YPG) showed the highest content of YP and the highest REL of CpLCY-β2 and CpCHX-β genes. Interestingly, the orange-pulp genotype (OPG) showed intermediate content of YP and intermediate REL of CpLCY-β2 and CpCHX-β genes. The highest content of β-carotene shown by OPG despite having an intermediate REL of the CpLCY-β2 genes, suggests a post-transcriptional regulation. Thus, the transcriptional level of the genes, directing the carotenoid biosynthesis pathway, can partially explain the accumulation of carotenoids during the postharvest ripening in C. papaya genotypes of contrasting pulp color. Copyright © 2017 Elsevier Ltd. All rights reserved.

Altering lipase activity and enantioselectivity in organic media using organo-soluble bases: Implication for rate-limiting proton transfer in acylation step.

PubMed

Chen, Chun-Chi; Chen, Teh-Liang; Tsai, Shau-Wei

2006-06-05

With the hydrolytic resolution of (R,S)-naproxen 2,2,2-trifluoroethyl esters via a partially purified papaya lipase (PCPL) in water-saturated isooctane as the model system, the enzyme activity, and enantioselectivty is altered by adding a variety of organo-soluble bases that act as either enzyme activators (i.e., TEA, MP, TOA, DPA, PY, and DMA) or enzyme inhibitors (i.e., PDP, DMAP, and PP). Triethylamine (TEA) is selected as the best enzyme activator as 2.24-fold increase of the initial rate for the (S)-ester is obtained when adding 120 mM of the base. By using an expanded Michaelis-Menten mechanism for the acylation step, the kinetic analysis indicates that the proton transfer for the breakdown of tetrahedral intermediates to acyl-enzyme intermediates is the rate-limiting step, or more sensitive than that for the formation of tetrahedral intermediates when the enzyme activators of different pKa are added. However, no correlation for the proton transfers in the acylation step is found when adding the bases acting as enzyme deactivators. Copyright 2006 Wiley Periodicals, Inc.

The mechanism of action of serine transhydroxymethylase

PubMed Central

Jordan, P. M.; Akhtar, M.

1970-01-01

1. The preparation of stereospecifically tritiated glycines and the determination of their absolute configurations by the use of d-amino acid oxidase are described. 2. The reaction catalysed by serine transhydroxymethylase, which results in the conversion of glycine into serine, has been separated into at least four partial reactions. It is suggested that the first event in this conversion is the formation of a Schiff base intermediate of glycine and pyridoxal phosphate. The next important step involves the removal of the 2S-hydrogen atom of glycine to give a carbanion intermediate. Experiments pertinent to the mechanism of conversion of this carbanion intermediate into serine are described. 3. The enzyme preparation catalysing the conversion of glycine into serine also participates in the conversion of glycine into threonine and allothreonine. In both these conversions, glycine → serine and glycine → threonine, the 2S-hydrogen atom of glycine is eliminated and the 2R-hydrogen atom of glycine is retained. 4. In the light of these experiments the mechanism of action of serine transhydroxymethylase is discussed. It is suggested that methylenetetrahydrofolate is the carrier of formaldehyde, from which formaldehyde may be liberated at the active site of the enzyme, thus allowing the overall reaction to take place. PMID:5414101

High-pressure applications in medicine and pharmacology

NASA Astrophysics Data System (ADS)

Silva, Jerson L.; Foguel, Debora; Suarez, Marisa; Gomes, Andre M. O.; Oliveira, Andréa C.

2004-04-01

High pressure has emerged as an important tool to tackle several problems in medicine and biotechnology. Misfolded proteins, aggregates and amyloids have been studied, which point toward the understanding of the protein misfolding diseases. High hydrostatic pressure (HHP) has also been used to dissociate non-amyloid aggregates and inclusion bodies. The diverse range of diseases that result from protein misfolding has made this theme an important research focus for pharmaceutical and biotech companies. The use of high pressure promises to contribute to identifying the mechanisms behind these defects and creating therapies against these diseases. High pressure has also been used to study viruses and other infectious agents for the purpose of sterilization and in the development of vaccines. Using pressure, we have detected the presence of a ribonucleoprotein intermediate, where the coat protein is partially unfolded but bound to RNA. These intermediates are potential targets for antiviral compounds. The ability of pressure to inactivate viruses, prions and bacteria has been evaluated with a view toward the applications of vaccine development and virus sterilization. Recent studies demonstrate that pressure causes virus inactivation while preserving the immunogenic properties. There is increasing evidence that a high-pressure cycle traps a virus in the 'fusion intermediate state', not infectious but highly immunogenic.

In situ XPS study of methanol reforming on PdGa near-surface intermetallic phases

PubMed Central

Rameshan, Christoph; Stadlmayr, Werner; Penner, Simon; Lorenz, Harald; Mayr, Lukas; Hävecker, Michael; Blume, Raoul; Rocha, Tulio; Teschner, Detre; Knop-Gericke, Axel; Schlögl, Robert; Zemlyanov, Dmitry; Memmel, Norbert; Klötzer, Bernhard

2012-01-01

In situ X-ray photoelectron spectroscopy and low-energy ion scattering were used to study the preparation, (thermo)chemical and catalytic properties of 1:1 PdGa intermetallic near-surface phases. Deposition of several multilayers of Ga metal and subsequent annealing to 503–523 K led to the formation of a multi-layered 1:1 PdGa near-surface state without desorption of excess Ga to the gas phase. In general, the composition of the PdGa model system is much more variable than that of its PdZn counterpart, which results in gradual changes of the near-surface composition with increasing annealing or reaction temperature. In contrast to near-surface PdZn, in methanol steam reforming, no temperature region with pronounced CO2 selectivity was observed, which is due to the inability of purely intermetallic PdGa to efficiently activate water. This allows to pinpoint the water-activating role of the intermetallic/support interface and/or of the oxide support in the related supported PdxGa/Ga2O3 systems, which exhibit high CO2 selectivity in a broad temperature range. In contrast, corresponding experiments starting on the purely bimetallic model surface in oxidative methanol reforming yielded high CO2 selectivity already at low temperatures (∼460 K), which is due to efficient O2 activation on PdGa. In situ detected partial and reversible oxidative Ga segregation on intermetallic PdGa is associated with total oxidation of intermediate C1 oxygenates to CO2. PMID:22875996

Coherence rephasing combined with spin-wave storage using chirped control pulses

NASA Astrophysics Data System (ADS)

Demeter, Gabor

2014-06-01

Photon-echo based optical quantum memory schemes often employ intermediate steps to transform optical coherences to spin coherences for longer storage times. We analyze a scheme that uses three identical chirped control pulses for coherence rephasing in an inhomogeneously broadened ensemble of three-level Λ systems. The pulses induce a cyclic permutation of the atomic populations in the adiabatic regime. Optical coherences created by a signal pulse are stored as spin coherences at an intermediate time interval, and are rephased for echo emission when the ensemble is returned to the initial state. Echo emission during a possible partial rephasing when the medium is inverted can be suppressed with an appropriate choice of control pulse wave vectors. We demonstrate that the scheme works in an optically dense ensemble, despite control pulse distortions during propagation. It integrates conveniently the spin-wave storage step into memory schemes based on a second rephasing of the atomic coherences.

Exhaust emission survey of an F100 afterburning turbofan engine at simulated altitude flight conditions

NASA Technical Reports Server (NTRS)

Moss, J. E.; Cullom, R. R.

1981-01-01

Emissions of carbon monoxide, total oxides of nitrogen, unburned hydrocarbons, and carbon dioxide from an F100, afterburning, two spool turbofan engine at simulated flight conditions are reported. For each flight condition emission measurements were made for two or three power levels from intermediate power (nonafterburning) through maximum afterburning. The data showed that emissions vary with flight speed, altitude, power level, and radial position across the nozzle. Carbon monoxide emissions were low for intermediate power (nonafterburning) and partial afterburning, but regions of high carbon monoxide were present downstream of the flame holder at maximum afterburning. Unburned hydrocarbon emissions were low for most of the simulated flight conditions. The local NOX concentrations and their variability with power level increased with increasing flight Mach number at constant altitude, and decreased with increasing altitude at constant Mach number. Carbon dioxide emissions were proportional to local fuel air ratio for all conditions.

Bending-related faulting and mantle serpentinization at the Middle America trench.

PubMed

Ranero, C R; Morgan, J Phipps; McIntosh, K; Reichert, C

2003-09-25

The dehydration of subducting oceanic crust and upper mantle has been inferred both to promote the partial melting leading to arc magmatism and to induce intraslab intermediate-depth earthquakes, at depths of 50-300 km. Yet there is still no consensus about how slab hydration occurs or where and how much chemically bound water is stored within the crust and mantle of the incoming plate. Here we document that bending-related faulting of the incoming plate at the Middle America trench creates a pervasive tectonic fabric that cuts across the crust, penetrating deep into the mantle. Faulting is active across the entire ocean trench slope, promoting hydration of the cold crust and upper mantle surrounding these deep active faults. The along-strike length and depth of penetration of these faults are also similar to the dimensions of the rupture area of intermediate-depth earthquakes.

Autothermal and partial oxidation reformer-based fuel processor, method for improving catalyst function in autothermal and partial oxidation reformer-based processors

DOEpatents

Ahmed, Shabbir; Papadias, Dionissios D.; Lee, Sheldon H. D.; Ahluwalia, Rajesh K.

2013-01-08

The invention provides a fuel processor comprising a linear flow structure having an upstream portion and a downstream portion; a first catalyst supported at the upstream portion; and a second catalyst supported at the downstream portion, wherein the first catalyst is in fluid communication with the second catalyst. Also provided is a method for reforming fuel, the method comprising contacting the fuel to an oxidation catalyst so as to partially oxidize the fuel and generate heat; warming incoming fuel with the heat while simultaneously warming a reforming catalyst with the heat; and reacting the partially oxidized fuel with steam using the reforming catalyst.

Catalytic and non-catalytic wet air oxidation of sodium dodecylbenzene sulfonate: kinetics and biodegradability enhancement.

PubMed

Suárez-Ojeda, María Eugenia; Kim, Jungkwon; Carrera, Julián; Metcalfe, Ian S; Font, Josep

2007-06-18

Wet air oxidation (WAO) and catalytic wet air oxidation (CWAO) were investigated as suitable precursors for the biological treatment of industrial wastewater containing sodium dodecylbenzene sulfonate (DBS). Two hours WAO semi-batch experiments were conducted at 15 bar of oxygen partial pressure (P(O2)) and at 180, 200 and 220 degrees C. It was found that the highest temperature provides appreciable total organic carbon (TOC) and chemical oxygen demand (COD) abatement of about 42 and 47%, correspondingly. Based on the main identified intermediates (acetic acid and sulfobenzoic acid) a reaction pathway for DBS and a kinetic model in WAO were proposed. In the case of CWAO experiments, seventy-two hours tests were done in a fixed bed reactor in continuous trickle flow regime, using a commercial activated carbon (AC) as catalyst. The temperature and P(O2) were 140-160 degrees C and 2-9 bar, respectively. The influence of the operating conditions on the DBS oxidation, the occurrence of oxidative coupling reactions over the AC, and the catalytic activity (in terms of substrate removal) were established. The results show that the AC without any supported active metal behaves bi-functional as adsorbent and catalyst, giving TOC conversions up to 52% at 160 degrees C and 2 bar of P(O2), which were comparable to those obtained in WAO experiments. Respirometric tests were completed before and after CWAO and to the main intermediates identified through the WAO and CWAO oxidation route. Then, the readily biodegradable COD (COD(RB)) of the CWAO and WAO effluents were found. Taking into account these results it was possible to compare whether or not the CWAO or WAO effluents were suitable for a conventional activated sludge plant inoculated with non adapted culture.

Physical, mechanical and electrochemical characterization of all-perovskite intermediate temperature solid oxide fuel cells

NASA Astrophysics Data System (ADS)

Mohammadi, Alidad

Strontium- and magnesium-doped lanthanum gallate (LSGM) has been considered as a promising electrolyte for solid oxide fuel cell (SOFC) systems in recent years due to its high ionic conductivity and chemical stability over a wide range of oxygen partial pressures and temperatures. This research describes synthesis, physical and mechanical behavior, electrochemical properties, phase evolution, and microstructure of components of an all-perovskite anode-supported intermediate temperature solid oxide fuel cell (ITSOFC), based on porous La 0.75Sr0.25Cr0.5Mn0.5O3 (LSCM) anode, La0.8Sr0.2Ga0.8Mg0.2O 2.8 (LSGM) electrolyte, and porous La0.6Sr0.4Fe 0.8Co0.2O3 (LSCF) cathode. The phase evolution of synthesized LSGM and LSCM powders has been investigated, and it has been confirmed that there is no reaction between LSGM and LSCM at sintering temperature. Using different amounts of poreformers and binders as well as controlling firing temperature, porosity of the anode was optimized while still retaining good mechanical integrity. The effect of cell operation conditions under dry hydrogen fuel on the SOFC open circuit voltage (OCV) and cell performance were also investigated. Characterization study of the synthesized LSGM indicates that sintering at 1500°C obtains higher electrical conductivity compared to the currently published results, while conductivity of pellets sintered at 1400°C and 1450°C would be slightly lower. The effect of sintering temperature on bulk and grain boundary resistivities was also discussed. The mechanical properties, such as hardness, Young's modulus, fracture toughness and modulus of rupture of the electrolyte were determined and correlated with scanning electron microscopy (SEM) morphological characterization. Linear thermal expansion and thermal expansion coefficient of LSGM were also measured.

Solid-state membrane module

DOEpatents

Hinklin, Thomas Ray; Lewinsohn, Charles Arthur

2015-06-30

A module for separating oxygen from an oxygen-containing gaseous mixture comprising planar solid-state membrane units, each membrane unit comprising planar dense mixed conducting oxides layers, planar channel-free porous support layers, and one or more planar intermediate support layers comprising at least one channeled porous support layer. The porosity of the planar channeled porous support layers is less than the porosity of the planar channel-free porous support layers.

Aqueous pyrite oxidation by dissolved oxygen and by ferric iron

USGS Publications Warehouse

Moses, Carl O.; Nordstrom, D. Kirk; Herman, Janet S.; Mills, Aaron L.

1987-01-01

Rates of aqueous, abiotic pyrite oxidation were measured in oxygen-saturated and anaerobic Fe(III)-saturated solutions with initial pH from 2 to 9. These studies included analyses of sulfite, thiosulfate, polythionates and sulfate and procedures for cleaning oxidation products from pyrite surfaces were evaluated. Pyrite oxidation in oxygen-saturated solutions produced (1) rates that were only slightly dependent on initial pH, (2) linear increases in sulfoxy anions and (3) thiosulfate and polythionates at pH > 3.9. Intermediate sulfoxy anions were observed only at high stirring rates. In anaerobic Fe(III)-saturated solutions, no intermediates were observed except traces of sulfite at pH 9. The faster rate of oxidation in Fe(III)-saturated solutions supports a reaction mechanism in which Fe(III) is the direct oxidant of pyrite in both aerobic and anaerobic systems. The proposal of this mechanism is also supported by theoretical considerations regarding the low probability of a direct reaction between paramagnetic molecular oxygen and diamagnetic pyrite. Results from a study of sphalerite oxidation support the hypothesis that thiosulfate is a key intermediate in sulfate production, regardless of the bonding structure of the sulfide mineral.

Treadmill training with partial body weight support compared with conventional gait training for low-functioning children and adolescents with nonspastic cerebral palsy: a two-period crossover study.

PubMed

Su, Ivan Y W; Chung, Kenny K Y; Chow, Daniel H K

2013-12-01

Partial body weight-supported treadmill training has been shown to be effective in gait training for patients with neurological disorders such as spinal cord injuries and stroke. Recent applications on children with cerebral palsy were reported, mostly on spastic cerebral palsy with single subject design. There is lack of evidence on the effectiveness of such training for nonspastic cerebral palsy, particularly those who are low functioning with limited intellectual capacity. This study evaluated the effectiveness of partial body weight-supported treadmill training for improving gross motor skills among these clients. A two-period randomized crossover design with repeated measures. A crossover design following an A-B versus a B-A pattern was adopted. The two training periods consisted of 12-week partial body weight-supported treadmill training (Training A) and 12-week conventional gait training (Training B) with a 10-week washout in between. Ten school-age participants with nonspastic cerebral palsy and severe mental retardation were recruited. The Gross Motor Function Measure-66 was administered immediately before and after each training period. Significant improvements in dimensions D and E of the Gross Motor Function Measure-66 and the Gross Motor Ability Estimator were obtained. Our findings revealed that the partial body weight-supported treadmill training was effective in improving gross motor skills for low-functioning children and adolescents with nonspastic cerebral palsy. .

Heritable IUGR and adult metabolic syndrome are reversible and associated with alterations in the metabolome following dietary supplementation of 1-carbon intermediates

PubMed Central

Seferovic, Maxim D.; Goodspeed, Danielle M.; Chu, Derrick M.; Krannich, Laura A.; Gonzalez-Rodriguez, Pablo J.; Cox, James E.; Aagaard, Kjersti M.

2015-01-01

Metabolic syndrome (MetS), following intrauterine growth restriction (IUGR), is epigenetically heritable. Recently, we abrogated the F2 adult phenotype with essential nutrient supplementation (ENS) of intermediates along the 1-carbon pathway. With the use of the same grandparental uterine artery ligation model, we profiled the F2 serum metabolome at weaning [postnatal day (d)21; n = 76] and adulthood (d160; n = 12) to test if MetS is preceded by alterations in the metabolome. Indicative of developmentally programmed MetS, adult F2, formerly IUGR rats, were obese (621 vs. 461 g; P < 0.0001), dyslipidemic (133 vs. 67 mg/dl; P < 0.001), and glucose intolerant (26 vs. 15 mg/kg/min; P < 0.01). Unbiased gas chromatography-mass spectrometry (GC-MS) profiling revealed 34 peaks corresponding to 12 nonredundant metabolites and 9 unknowns to be changing at weaning [false discovery rate (FDR) < 0.05]. Markers of later-in-life MetS included citric acid, glucosamine, myoinositol, and proline (P < 0.03). Hierarchical clustering revealed grouping by IUGR lineage and supplementation at d21 and d160. Weanlings grouped distinctly for ENS and IUGR by partial least-squares discriminate analysis (PLS-DA; P < 0.01), whereas paternal and maternal IUGR (IUGRpat/IUGRmat, respectively) control-fed rats, destined for MetS, had a distinct metabolome at weaning (randomForest analysis; class error < 0.1) and adulthood (PLS-DA; P < 0.05). In sum, we have found that alterations in the metabolome accompany heritable IUGR, precede adult-onset MetS, and are partially amenable to dietary intervention.—Seferovic, M. D., Goodspeed, D. M., Chu, D. M., Krannich, L. A., Gonzalez-Rodriguez, P. J., Cox, J. E., Aagaard, K. M. Heritable IUGR and adult metabolic syndrome are reversible and associated with alterations in the metabolome following dietary supplementation of one-carbon intermediates. PMID:25757570

Survival outcome of intermediate risk neuroblastoma at Children Cancer Hospital Egypt.

PubMed

Elzomor, Hossam; Ahmed, Gehad; Elmenawi, Salma; Elkinaai, Naglaa; Refaat, Amal; Soliman, Sonya; Abdelwahab, Mai Amr; Zaghloul, Mohamed Saad; Fawzy, Mohamed

2018-03-01

The study aims to evaluate survival outcome in newly diagnosed pediatric intermediate risk neuroblastoma patients treated at the Children Cancer Hospital - Egypt and their relation to various clinical and pathological factors. The study included stage 3 patients <1.5 years, children 1.5 years or older with stage 3 disease and favorable histopathological features, infants (<1 year) with International Neuroblastoma Staging System (INSS) stage 4 disease, stage 4 children 1-1.5 years with favorable biology, and infants stage 4 s (with unfavorable biologic features). Patients received systemic chemotherapy, in the form of etoposide and carboplatin alternating with cyclophosphamide, doxorubicin and vincristine, administered at 3-week intervals, with a total of 6 or 8 cycles guided by reaching objective overall response (complete/very good partial/partial response). The study included 136 patients, 67 males and 69 females. 101 patients had abdominal primary tumors, 28 had mediastinal masss and 7 with masses in the neck; 68% were stage 3 and the remaining (n = 44) had metastatic disease. The three-year overall survival (OS) and event-free survival (EFS) estimates were 94% ± 2% and 90.9% ± 2.5%, respectively. OS and EFS by gender, age, pathology and INPC were all statistically not significantly different. Moreover, OS for patients having surgery versus no surgery (inoperable residual only) was statistically significant (98.4% ± 1.6% & 88.7% ± 5.3%, respectively, p = .034). A very high rate of survival is currently achievable in patients with intermediate risk neuroblastoma by chemotherapy or chemotherapy and surgery. In addition to response, our plan is to adopt biologically-based treatment to reduce treatment-induced complications among survivors. Copyright © 2018 National Cancer Institute, Cairo University. Production and hosting by Elsevier B.V. All rights reserved.

General relativistic corrections to the weak lensing convergence power spectrum

NASA Astrophysics Data System (ADS)

Giblin, John T.; Mertens, James B.; Starkman, Glenn D.; Zentner, Andrew R.

2017-11-01

We compute the weak lensing convergence power spectrum, Cℓκκ, in a dust-filled universe using fully nonlinear general relativistic simulations. The spectrum is then compared to more standard, approximate calculations by computing the Bardeen (Newtonian) potentials in linearized gravity and partially utilizing the Born approximation. We find corrections to the angular power spectrum amplitude of order ten percent at very large angular scales, ℓ˜2 - 3 , and percent-level corrections at intermediate angular scales of ℓ˜20 - 30 .

N-Methylamino Pyrimidyl Amides (MAPA): Highly Reactive, Electronically-Activated Amides in Catalytic N-C(O) Cleavage.

PubMed

Meng, Guangrong; Lalancette, Roger; Szostak, Roman; Szostak, Michal

2017-09-01

Despite recent progress in catalytic cross-coupling technologies, the direct activation of N-alkyl-N-aryl amides has been a challenging transformation. Here, we report the first Suzuki cross-coupling of N-methylamino pyrimidyl amides (MAPA) enabled by the controlled n N → π Ar conjugation and the resulting remodeling of the partial double bond character of the amide bond. The new mode of amide activation is suitable for generating acyl-metal intermediates from unactivated primary and secondary amides.

Magnetic anisotropy and order parameter in nanostructured CoPt particles

NASA Astrophysics Data System (ADS)

Komogortsev, S. V.; Iskhakov, R. S.; Zimin, A. A.; Filatov, E. Yu.; Korenev, S. V.; Shubin, Yu. V.; Chizhik, N. A.; Yurkin, G. Yu.; Eremin, E. V.

2013-10-01

The correlation of magnetic anisotropy energy with order parameter in the crystallites of CoPt nanostructured particles prepared by thermal decomposition and further annealing has been studied by investigation of the approach magnetization to saturation curves and x-ray powder diffraction pattern profiles. It is shown that magnetic anisotropy energy value in partially ordered CoPt crystallite could be described as an intermediate case between two extremes, corresponding to either single or several c-domains of L10 phase in crystallite.

Nitrolysis of the CN Single Bond and Related Chemistry of Nitro and Nitroso Groups.

DTIC Science & Technology

1988-03-01

oxime of be 4,5-diphenyl-l-triphenylmethoxy-l,23- triazole (11). It was benzoyl cyanide (Scheme 6), for which radical intermediates hydrolysed by...S-Pnitroxide (a radical scavenger) or benzoyl peroxide (a radical *PhC CCN)- NO2 Ag PhCON--CPh suc)I I source). A partial extension of the overall...two anomethylenenitronate anion. (Attempts to prepare the pathways for fragmentation of the ester (3) (C,.H,0 N.O,): one ketenimine (15) by a

Transition metal partially supported graphene: Magnetism and oscillatory electrostatic potentials

DOE PAGES

Liu, Xiaojie; Wang, Cai-Zhuang

2017-08-07

Using first-principles calculations here, we show that Mn and Cr layers under graphene exhibit almost zero magnetic moment due to anti-ferromagnetic order, while ferromagnetic coupling in Fe, Co, and Ni leads to large magnetic moment. The transition metal partially supported graphene, with a mixture of supported and pristine areas, exhibits an oscillatory electrostatic potential, thus alternating the electric field across the supported and pristine areas. Such an effect can be utilized to control mass transport and nanostructure self-organization on graphene at the atomic level.

Transition metal partially supported graphene: Magnetism and oscillatory electrostatic potentials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Xiaojie; Wang, Cai-Zhuang

Using first-principles calculations here, we show that Mn and Cr layers under graphene exhibit almost zero magnetic moment due to anti-ferromagnetic order, while ferromagnetic coupling in Fe, Co, and Ni leads to large magnetic moment. The transition metal partially supported graphene, with a mixture of supported and pristine areas, exhibits an oscillatory electrostatic potential, thus alternating the electric field across the supported and pristine areas. Such an effect can be utilized to control mass transport and nanostructure self-organization on graphene at the atomic level.

Providing effective and preferred care closer to home: a realist review of intermediate care.

PubMed

Pearson, Mark; Hunt, Harriet; Cooper, Chris; Shepperd, Sasha; Pawson, Ray; Anderson, Rob

2015-11-01

Intermediate care is one of the number of service delivery models intended to integrate care and provide enhanced health and social care services closer to home, especially to reduce reliance on acute care hospital beds. In order for health and social care practitioners, service managers and commissioners to make informed decisions, it is vital to understand how to implement the admission avoidance and early supported discharge components of intermediate care within the context of local care systems. This paper reports the findings of a theory-driven (realist) review conducted in 2011-2012. A broad range of evidence contained in 193 sources was used to construct a conceptual framework for intermediate care. This framework forms the basis for exploring factors at service user, professional and organisational levels that should be considered when designing and delivering intermediate care services within a particular local context. Our synthesis found that involving service users and their carers in collaborative decision-making about the objectives of care and the place of care is central to achieving the aims of intermediate care. This pivotal involvement of the service user relies on practitioners, service managers and commissioners being aware of the impact that organisational structures at the local level can have on enabling or inhibiting collaborative decision-making and care co-ordination. Through all interactions with service users and their care networks, health and social care professionals should establish the meaning which alternative care environments have for different service users. Doing so means decisions about the best place of care will be better informed and gives service users choice. This in turn is likely to support psychological and social stability, and the attainment of functional goals. At an organisational level, integrated working can facilitate the delivery of intermediate care, but there is not a straightforward relationship between integrated organisational processes and integrated professional practice. © 2015 John Wiley & Sons Ltd.

Integrated modulation of phorbol ester-induced Raf activation in EL4 lymphoma cells.

PubMed

Han, Shujie; Meier, Kathryn E

2009-05-01

The EL4 murine lymphoma cell line exists in variant phenotypes that differ with respect to responses to the tumor promoter phorbol 12-myristate 13-acetate (PMA1). Previous work showed that "PMA-sensitive" cells, characterized by a high magnitude of PMA-induced Erk activation, express RasGRP, a phorbol ester receptor that directly activates Ras. In "PMA-resistant" and "intermediate" EL4 cell lines, PMA induces Erk activation to lesser extents, but with a greater response in intermediate cells. In the current study, these cell lines were used to examine mechanisms of Raf-1 modulation. Phospho-specific antibodies were utilized to define patterns and kinetics of Raf-1 phosphorylation on several sites. Further studies showed that Akt is constitutively activated to a greater extent in PMA-resistant than in PMA-sensitive cells, and also to a greater extent in resistant than intermediate cells. Akt negatively regulates Raf-1 activation (Ser259), partially explaining the difference between resistant and intermediate cells. Erk activation exerts negative feedback on Raf-1 (Ser289/296/301), thus resulting in earlier termination of the signal in cells with a higher level of Erk activation. RKIP, a Raf inhibitory protein, is expressed at higher levels in resistant cells than in sensitive or intermediate cells. Knockdown of RKIP increases Erk activation and also negative feedback. In conclusion, this study delineates Raf-1 phosphorylation events occurring in response to PMA in cell lines with different extents of Erk activation. Variations in the levels of expression and activation of multiple signaling proteins work in an integrated fashion to modulate the extent and duration of Erk activation.

Validity of Partial Protocols to Assess the Prevalence of Periodontal Outcomes and Associated Sociodemographic and Behavior Factors in Adolescents and Young Adults

PubMed Central

Peres, Marco A.; Peres, Karen G.; Cascaes, Andreia M.; Correa, Marcos B.; Demarco, Flávio F.; Hallal, Pedro C.; Horta, Bernardo L.; Gigante, Denise P.; Menezes, Ana B.

2012-01-01

Background Most studies comparing prevalence of periodontal disease and risk factors by using partial protocols were performed in adult populations, with several studies being conducted in clinical settings. The aim of this study is to assess the accuracy of partial protocols in estimating the prevalence of periodontal outcomes in adolescents and young adults from two population-based birth cohorts from Pelotas, Brazil, and to assess differences in the estimation and strength of the effect measures when partial protocols are adopted compared to full-mouth examination. Methods Gingival bleeding at probing among adolescents (n = 339) and young adults (n = 720) and dental calculus and periodontal probing depth among young adults were assessed using full-mouth examinations and four partial protocols: Ramfjord teeth (RT), community periodontal index (CPI), and two random diagonal quadrants (1 and 3, 2 and 4). Socioeconomic, demographic, and periodontal health-related variables were also collected. Sensitivity, absolute and relative bias, and inflation factors were calculated. Prevalence ratio for each periodontal outcome for the risk factors was estimated. Results Two diagonal quadrants showed better accuracy; RT had the worst, whereas CPI presented an intermediate pattern when compared to full-mouth examination. For bleeding assessment in adolescence, RT and CPI underestimated by 18.4% and 16.2%, respectively, the true outcome prevalence, whereas among young adults, all partial protocols underestimated the prevalence. All partial protocols presented similar magnitude of association measures for all investigated periodontal potential risk factors. Conclusion Two diagonal quadrants protocol may be effective in identifying the risk factors for the most relevant periodontal outcomes in adolescence and in young adulthood. PMID:21859320

Validity of partial protocols to assess the prevalence of periodontal outcomes and associated sociodemographic and behavior factors in adolescents and young adults.

PubMed

Peres, Marco A; Peres, Karen G; Cascaes, Andreia M; Correa, Marcos B; Demarco, Flávio F; Hallal, Pedro C; Horta, Bernardo L; Gigante, Denise P; Menezes, Ana B

2012-03-01

Most studies comparing prevalence of periodontal disease and risk factors by using partial protocols were performed in adult populations, with several studies being conducted in clinical settings. The aim of this study is to assess the accuracy of partial protocols in estimating the prevalence of periodontal outcomes in adolescents and young adults from two population-based birth cohorts from Pelotas, Brazil, and to assess differences in the estimation and strength of the effect measures when partial protocols are adopted compared to full-mouth examination. Gingival bleeding at probing among adolescents (n = 339) and young adults (n = 720) and dental calculus and periodontal probing depth among young adults were assessed using full-mouth examinations and four partial protocols: Ramfjord teeth (RT), community periodontal index (CPI), and two random diagonal quadrants (1 and 3, 2 and 4). Socioeconomic, demographic, and periodontal health-related variables were also collected. Sensitivity, absolute and relative bias, and inflation factors were calculated. Prevalence ratio for each periodontal outcome for the risk factors was estimated. Two diagonal quadrants showed better accuracy; RT had the worst, whereas CPI presented an intermediate pattern when compared to full-mouth examination. For bleeding assessment in adolescence, RT and CPI underestimated by 18.4% and 16.2%, respectively, the true outcome prevalence, whereas among young adults, all partial protocols underestimated the prevalence. All partial protocols presented similar magnitude of association measures for all investigated periodontal potential risk factors. Two diagonal quadrants protocol may be effective in identifying the risk factors for the most relevant periodontal outcomes in adolescence and in young adulthood.

Turbulence in the Ott-Antonsen equation for arrays of coupled phase oscillators

NASA Astrophysics Data System (ADS)

Wolfrum, M.; Gurevich, S. V.; Omel'chenko, O. E.

2016-02-01

In this paper we study the transition to synchrony in an one-dimensional array of oscillators with non-local coupling. For its description in the continuum limit of a large number of phase oscillators, we use a corresponding Ott-Antonsen equation, which is an integro-differential equation for the evolution of the macroscopic profiles of the local mean field. Recently, it was reported that in the spatially extended case at the synchronisation threshold there appear partially coherent plane waves with different wave numbers, which are organised in the well-known Eckhaus scenario. In this paper, we show that for Kuramoto-Sakaguchi phase oscillators the phase lag parameter in the interaction function can induce a Benjamin-Feir-type instability of the partially coherent plane waves. The emerging collective macroscopic chaos appears as an intermediate stage between complete incoherence and stable partially coherent plane waves. We give an analytic treatment of the Benjamin-Feir instability and its onset in a codimension-two bifurcation in the Ott-Antonsen equation as well as a numerical study of the transition from phase turbulence to amplitude turbulence inside the Benjamin-Feir unstable region.

Flame Spray Strain Gages with Improved Durability and Lifetimes

NASA Technical Reports Server (NTRS)

Fralick, Gustave (Technical Monitor); Gregory, Otto

2003-01-01

The focus of this APP research program was to improve the bond coats used in the fabrication of flame sprayed instrumentation. Typically. a bond coat is applied to a superalloy surface prior to the application of a thin dielectric coating onto which instrumentation is placed. After affixing the instrumentation, a much thicker ceramic topcoat is typically applied to protect the instrumentation from harsh environments. The fatigue life of NiCoCrAlY coated superalloys was extended beyond current state-of-the-art by relatively simple and cost effective means. Heat treatment in reduced oxygen partial pressures at 1750 to 1800 F effectively doubled the fatigue life of NiCoCrAlY coated substrates relative to as-sprayed substrates and when used in conjunction with platinum diffusion barriers yielded a four fold increase in the fatigue life of NiCoCrAlY coated substrates. Further improvements in the fatigue life of thermally sprayed coatings were made by employing intermediate coatings, which minimized thermal expansion differences between the bond coat and top coat. Combinatorial chemistry experiments yielded an optimum composition for an intermediate TCE matching coating that showed considerable promise in extending the fatigue life of thermal spray instrumentation. The intermediate coating had two functions: to reduce the surface roughness of the peaks and valleys associated with the as-sprayed NiCoCrAlY bond coat, and to produce a thin layer of a mixture of Al2O3 and NiCoCrAlY that exhibited an intermediate TCE. The optimal composition of the intermediate coating consisted of 60 wt% Al2O3 and 40 wt% NiCoCrAlY, as determined by energy dispersive analysis of x-rays (EDS). Intermediate coatings having this composition were prepared by physical vapor deposition and the resulting coating systems are being evaluated in our test facility.

Communication Efficient Gaussian Elimination with Partial Pivoting using a Shape Morphing Data Layout

DTIC Science & Technology

2013-02-21

support comes from ParLab affiliates National Instruments, Nokia, NVIDIA , Oracle and Samsung, as well as MathWorks. Research is also supported by DOE...affiliates National Instruments, Nokia, NVIDIA , Oracle and Samsung, as well as MathWorks. Research is also supported by DOE grants DE-SC0004938, DE-SC0005136...International Business Machines Company , 1966. [17] S. Toledo. Locality of reference in LU decomposition with partial pivoting. SIAM J. Matrix Anal. Appl., 18

Positive Adult Support and Depression Symptoms in Adolescent Females: The Partially Mediating Role of Eating Disturbances

ERIC Educational Resources Information Center

Linville, Deanna; O'Neil, Maya; Huebner, Angela

2011-01-01

This study examined linkages between depression symptoms (DEP) and positive adult support (PAS) in female adolescents and the partially mediating influence of eating disturbances (ED). Structural equation modeling was used to establish measurement models for each of the latent constructs, determine the relationships among the latent constructs,…

Allosteric Partial Inhibition of Monomeric Proteases. Sulfated Coumarins Induce Regulation, not just Inhibition, of Thrombin

PubMed Central

Verespy III, Stephen; Mehta, Akul Y.; Afosah, Daniel; Al-Horani, Rami A.; Desai, Umesh R.

2016-01-01

Allosteric partial inhibition of soluble, monomeric proteases can offer major regulatory advantages, but remains a concept on paper to date; although it has been routinely documented for receptors and oligomeric proteins. Thrombin, a key protease of the coagulation cascade, displays significant conformational plasticity, which presents an attractive opportunity to discover small molecule probes that induce sub-maximal allosteric inhibition. We synthesized a focused library of some 36 sulfated coumarins to discover two agents that display sub-maximal efficacy (~50%), high potency (<500 nM) and high selectivity for thrombin (>150-fold). Michaelis-Menten, competitive inhibition, and site-directed mutagenesis studies identified exosite 2 as the site of binding for the most potent sulfated coumarin. Stern-Volmer quenching of active site-labeled fluorophore suggested that the allosteric regulators induce intermediate structural changes in the active site as compared to those that display ~80–100% efficacy. Antithrombin inactivation of thrombin was impaired in the presence of the sulfated coumarins suggesting that allosteric partial inhibition arises from catalytic dysfunction of the active site. Overall, sulfated coumarins represent first-in-class, sub-maximal inhibitors of thrombin. The probes establish the concept of allosteric partial inhibition of soluble, monomeric proteins. This concept may lead to a new class of anticoagulants that are completely devoid of bleeding. PMID:27053426

Autothermal Processing of Renewable Liquids

NASA Astrophysics Data System (ADS)

Kruger, Jacob Scott

The vast majority of petrochemicals are synthesized from just six building block molecules, but current feedstocks are an unsustainable resource with negative externalities. Biomass represents a potentially sustainable feedstock, but needs densification, preferably to a liquid form, to be a suitable replacement. Fermentation to butanol and pyrolysis to bio-oil are two promising liquid intermediates. Catalytic partial oxidation (CPO) of the liquid intermediates over noble metal catalysts, which converts the liquids primarily into syngas and light olefins, is a promising technique for processing densified biomass. The study of liquids at high temperatures requires consideration of a range of complex phenomena, including boiling behavior on hot surfaces, reactions of the feed molecules at high temperatures and on catalyst surfaces, and interactions of impurities in the liquid with the catalyst. Chapter 2 deals with the behavior of the transient liquid that forms when cellulose, a major constituent of biomass, is pyrolized. Fast photography experiments and numerical simulations are performed to show that the aerosols formed in the boiling of this liquid are capable of transporting nonvolatile fragments of biomass intact into the gas phase. These nonvolatile fragments have significant implications in the storage and downstream processing of bio-oil. Some of the behavior of bio-oil at high temperature may also be explained by the variety of molecules in the liquid. Many different functional groups are present, each with its own set of chemical reactions in combustion, pyrolysis, and partial oxidation on a metal catalyst. Chapters 3 and 4 investigate these reactions through a survey of two-carbon surrogates of the functional group classes found in bio-oil. Chapter 3 examines reactions occuring in the complete CPO system over Pt and Rh catalysts, and in the complete system absent O 2. The selectivity data from each molecule and the surface science literature of each molecule are used to propose a reaction mechanism over the catalyst surface. Chapter 4 investigates the reactions that may be occurring in the gas phase and over the alpha-Al2O3 foam monolith support. Significant gas-phase chemistry is likely present in the autothermal reactor, although different temperature gradients between the autothermal reactions and the externally heated tube makes quantification of the amount of homogeneous chemistry in the autothermal system impossible. The alpha-Al2O 3 support may serve as a heat transfer medium and radical quencher (due to its foam structure with small-diameter pores), but not likely acid catalysis, as selectivity to dehydration products was similar both with and without the foam support. Because butanol is another promising liquid intermediate in biomass processing, a series of experiments with butanol in an CPO reactor was also carried out. Chapter 5 compares the four butanol isomers in a CPO reactor over Pt, PtCe, Rh, and RhCe catalysts. The reactivity of tert-butanol was as high or higher than the other alcohols, indicating that the lack of a carbonyl decomposition path does not necessarily in uence the reactivity of the molecule. Rather, the reactivity appeared to be more a function of the initial pyrolysis temperature of the alcohol. Thus, much of the initial chemistry of the higher alcohols in a CPO reactor may be homogeneous. The main function of the catalyst may be to decompose the intermediate carbonyls and alkenes to syngas. To that end, the PtCe had significantly lower reforming activity than the other catalysts, evidenced by the lower selectivity to CO and H2 and generally higher temperatures. Selectivity to syngas and light olefins was high and tunable depending on feed ratios, indicating the potential of CPO to provide petrochemical building blocks from butanol. Chapter 6 combines CPO with a water-gas shift (WGS) stage and investigates the addition of steam to isobutanol for the production of a high-purity H2 stream. A RhCe catalyst was used in the CPO stage to convert 100% of the isobutanol feed to primarily equilibrium products, although a non-negligible fraction of intermediate isobutryaldehyde, propylene and isobutene. The use of a PtCe catalyst directly downstream allowed the incorporation of a high-temperature WGS stage with no external heat addition. Concentration of CO in the exit stream ≤ 3%, and H2 selectivity ≥ 100% (based on H from isobutanol) was achieved, similar to industrial high-temperature WGS operations. Additionally, the use of a PtCe WGS catalyst allowed conversion of intermediate products remaining from the CPO stage, indicating the robustness of the CPO-WGS system. Finally, because any feedstock intended to produce petrochemical feedstocks will contain impurities, Chapter 7 investigates the durability of a RhCe catalyst over several hundred hours with CPO of food-grade glycerol. This feedstock contains ppm levels of Fe and several other impurities. Despite several perturbations to the system and the addition of impurity levels comparable to catalyst loading by the end of the test, the catalyst maintained 100% conversion of glycerol to equilibrium products throughout the experiment, although some loss of WGS activity was observed. In Chapter 8, several experiments are proposed to strengthen the conclusions of the experiments described in the previous chapters, including co-feeding of radicalscavenging molecules, in-situ spectroscopic studies, and mechanism validation with the current data. Further study of boiling phenomena is also proposed, and some preliminary results are presented. Additionally, integration of photochemistry into a CPO reactor is proposed as a method of improving catalyst durability for processing particularly recalcitrant feedstocks. The ability of CPO to handle high-moisture feedstocks may allow for its use in processing aquatic biomass; a potential design for a photobioreactor for algae cultivation with integration of a CPO reactor is described. Finally, the study of ethanol conversion to butanol through a Guerbet-type reaction is proposed. A Guerbet stage would function particularly well downstream of a CPO reactor because it requires heat, dehydrogenated alcohols, and H 2 addition. Although a comprehensive understanding of the phenomena occuring in a CPO reactor is far from available, the diversity of applications in which sustainably produced syngas and heat find use suggests that CPO reaction engineering is an important area of research. This thesis offers preliminary insight into some of the phenomena and applications of catalytic partial oxidation.

Functional Green-Tuned Proteorhodopsin from Modern Stromatolites

PubMed Central

Albarracín, Virginia Helena; Kraiselburd, Ivana; Bamann, Christian; Wood, Phillip G.; Bamberg, Ernst; Farias, María Eugenia; Gärtner, Wolfgang

2016-01-01

The sequenced genome of the poly-extremophile Exiguobacterium sp. S17, isolated from modern stromatolites at Laguna Socompa (3,570 m), a High-Altitude Andean Lake (HAAL) in Argentinean Puna revealed a putative proteorhodopsin-encoding gene. The HAAL area is exposed to the highest UV irradiation on Earth, making the microbial community living in the stromatolites test cases for survival strategies under extreme conditions. The heterologous expressed protein E17R from Exiguobacterium (248 amino acids, 85% sequence identity to its ortholog ESR from E. sibiricum) was assembled with retinal displaying an absorbance maximum at 524 nm, which makes it a member of the green-absorbing PR-subfamily. Titration down to low pH values (eventually causing partial protein denaturation) indicated a pK value between two and three. Global fitting of data from laser flash-induced absorption changes gave evidence for an early red-shifted intermediate (its formation being below the experimental resolution) that decayed (τ1 = 3.5 μs) into another red-shifted intermediate. This species decayed in a two-step process (τ2 = 84 μs, τ3 = 11 ms), to which the initial state of E17-PR was reformed with a kinetics of 2 ms. Proton transport capability of the HAAL protein was determined by BLM measurements. Additional blue light irradiation reduced the proton current, clearly identifying a blue light absorbing, M-like intermediate. The apparent absence of this intermediate is explained by closely matching formation and decay kinetics. PMID:27187791

Functional Green-Tuned Proteorhodopsin from Modern Stromatolites.

PubMed

Albarracín, Virginia Helena; Kraiselburd, Ivana; Bamann, Christian; Wood, Phillip G; Bamberg, Ernst; Farias, María Eugenia; Gärtner, Wolfgang

2016-01-01

The sequenced genome of the poly-extremophile Exiguobacterium sp. S17, isolated from modern stromatolites at Laguna Socompa (3,570 m), a High-Altitude Andean Lake (HAAL) in Argentinean Puna revealed a putative proteorhodopsin-encoding gene. The HAAL area is exposed to the highest UV irradiation on Earth, making the microbial community living in the stromatolites test cases for survival strategies under extreme conditions. The heterologous expressed protein E17R from Exiguobacterium (248 amino acids, 85% sequence identity to its ortholog ESR from E. sibiricum) was assembled with retinal displaying an absorbance maximum at 524 nm, which makes it a member of the green-absorbing PR-subfamily. Titration down to low pH values (eventually causing partial protein denaturation) indicated a pK value between two and three. Global fitting of data from laser flash-induced absorption changes gave evidence for an early red-shifted intermediate (its formation being below the experimental resolution) that decayed (τ1 = 3.5 μs) into another red-shifted intermediate. This species decayed in a two-step process (τ2 = 84 μs, τ3 = 11 ms), to which the initial state of E17-PR was reformed with a kinetics of 2 ms. Proton transport capability of the HAAL protein was determined by BLM measurements. Additional blue light irradiation reduced the proton current, clearly identifying a blue light absorbing, M-like intermediate. The apparent absence of this intermediate is explained by closely matching formation and decay kinetics.

Solid oxide fuel cell generator

DOEpatents

Draper, Robert; George, Raymond A.; Shockling, Larry A.

1993-01-01

A solid oxide fuel cell generator has a pair of spaced apart tubesheets in a housing. At least two intermediate barrier walls are between the tubesheets and define a generator chamber between two intermediate buffer chambers. An array of fuel cells have tubes with open ends engaging the tubesheets. Tubular, axially elongated electrochemical cells are supported on the tubes in the generator chamber. Fuel gas and oxidant gas are preheated in the intermediate chambers by the gases flowing on the other side of the tubes. Gas leakage around the tubes through the tubesheets is permitted. The buffer chambers reentrain the leaked fuel gas for reintroduction to the generator chamber.

Abandoning the ship: spontaneous mass exodus of Clinostomum complanatum (Rudolphi, 1814) progenetic metecercariae from the dying intermediate host Trichogaster fasciatus (Bloch & Schneider, 1801).

PubMed

Rizvi, Asim; Alam, Md Maroof; Parveen, Saltanat; Saleemuddin, M; Abidi, S M A

2012-04-01

The dramatic and spontaneous exodus of live Clinostomum complanatum progenetic metacercaria from the gill slits of the dying intermediate host, Trichogaster fasciatus is reported. Basic water parameter tests for dissolved oxygen, pH and temperature revealed slightly lower level of dissolved oxygen in tank water used for water change. To the best of our knowledge, it is the first report of a digenean metacercariae, en mass leaving their intermediate host, upon its death in search of an alternative host to support their survival and help in continuing their life cycle.

Photocrystallographic observation of halide-bridged intermediates in halogen photoeliminations.

PubMed

Powers, David C; Anderson, Bryce L; Hwang, Seung Jun; Powers, Tamara M; Pérez, Lisa M; Hall, Michael B; Zheng, Shao-Liang; Chen, Yu-Sheng; Nocera, Daniel G

2014-10-29

Polynuclear transition metal complexes, which frequently constitute the active sites of both biological and chemical catalysts, provide access to unique chemical transformations that are derived from metal-metal cooperation. Reductive elimination via ligand-bridged binuclear intermediates from bimetallic cores is one mechanism by which metals may cooperate during catalysis. We have established families of Rh2 complexes that participate in HX-splitting photocatalysis in which metal-metal cooperation is credited with the ability to achieve multielectron photochemical reactions in preference to single-electron transformations. Nanosecond-resolved transient absorption spectroscopy, steady-state photocrystallography, and computational modeling have allowed direct observation and characterization of Cl-bridged intermediates (intramolecular analogues of classical ligand-bridged intermediates in binuclear eliminations) in halogen elimination reactions. On the basis of these observations, a new class of Rh2 complexes, supported by CO ligands, has been prepared, allowing for the isolation and independent characterization of the proposed halide-bridged intermediates. Direct observation of halide-bridged structures establishes binuclear reductive elimination as a viable mechanism for photogenerating energetic bonds.

Observation of the time-course for peptidoglycan lipid intermediate II polymerization by Staphylococcus aureus monofunctional transglycosylase.

PubMed

Braddick, Darren; Sandhu, Sandeep; Roper, David I; Chappell, Michael J; Bugg, Timothy D H

2014-08-01

The polymerization of lipid intermediate II by the transglycosylase activity of penicillin-binding proteins (PBPs) represents an important target for antibacterial action, but limited methods are available for quantitative assay of this reaction, or screening potential inhibitors. A new labelling method for lipid II polymerization products using Sanger's reagent (fluoro-2,4-dinitrobenzene), followed by gel permeation HPLC analysis, has permitted the observation of intermediate polymerization products for Staphylococcus aureus monofunctional transglycosylase MGT. Peak formation is inhibited by 6 µM ramoplanin or enduracidin. Characterization by mass spectrometry indicates the formation of tetrasaccharide and octasaccharide intermediates, but not a hexasaccharide intermediate, suggesting a dimerization of a lipid-linked tetrasaccharide. Numerical modelling of the time-course data supports a kinetic model involving addition to lipid-linked tetrasaccharide of either lipid II or lipid-linked tetrasaccharide. Observation of free octasaccharide suggests that hydrolysis of the undecaprenyl diphosphate lipid carrier occurs at this stage in peptidoglycan transglycosylation. © 2014 The Authors.

Supported metal alloy catalysts

DOEpatents

Barrera, Joseph; Smith, David C.

2000-01-01

A process of preparing a Group IV, V, or VI metal carbonitride including reacting a Group IV, V, or VI metal amide complex with ammonia to obtain an intermediate product; and, heating the intermediate product to temperatures and for times sufficient to form a Group IV, V, or VI metal carbonitride is provided together with the product of the process and a process of reforming an n-alkane by use of the product.

Degradation of caffeine by conductive diamond electrochemical oxidation.

PubMed

Indermuhle, Chloe; Martín de Vidales, Maria J; Sáez, Cristina; Robles, José; Cañizares, Pablo; García-Reyes, Juan F; Molina-Díaz, Antonio; Comninellis, Christos; Rodrigo, Manuel A

2013-11-01

The use of Conductive-Diamond Electrochemical Oxidation (CDEO) and Sonoelectrochemical Oxidation (CDSEO) has been evaluated for the removal of caffeine of wastewater. Effects of initial concentration, current density and supporting electrolyte on the process efficiency are assessed. Results show that caffeine is very efficiently removed with CDEO and that depletion of caffeine has two stages depending on its concentration. At low concentrations, opposite to what it is expected in a mass-transfer controlled process, the efficiency increases with current density very significantly, suggesting a very important role of mediated oxidation processes on the removal of caffeine. In addition, the removal of caffeine is faster than TOC, indicating the formation of reaction intermediates. The number and relative abundance of them depend on the operating conditions and supporting electrolyte used. In chloride media, removal of caffeine is faster and more efficiently, although the occurrence of more intermediates takes place. CDSEO does not increase the efficiency of caffeine removal, but it affects to the formation of intermediates. A detailed characterization of intermediates by liquid chromatography time-of-flight mass spectrometry seems to indicate that the degradation of caffeine by CDEO follows an oxidation pathway similar to mechanism proposed by other advanced oxidation processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Thiols in Hydrothermal Solution: Standard Partial Molal Properties and Their Role in the Organic Geochemistry of Hydrothermal Environments

NASA Technical Reports Server (NTRS)

Schulte, Mitchell D.; Rogers, Karyn L.; DeVincenzi, D. (Technical Monitor)

2001-01-01

Modern seafloor hydrothermal systems are locations where great varieties of geochemistry occur due to the enormous disequilibrium between vent fluids and seawater. The disequilibrium geochemistry has been hypothesized to include reactions to synthesize organic compounds. Despite the incomplete understanding of the carbon budget in hydrothermal systems, the organic geochemistry of these sites has received little attention. Experimental simulations of these environments, however, indicate that organic compounds may have difficulty forming in a purely aqueous environment. On the other hand, thiols, thioesters and disulfides have been implicated as reaction intermediates between CO or CO2 in experiments of carbon reduction in hydrothermal environments, as well as in a variety of biological processes and other abiotic reactions. The reduction of CO2 to thesis, for example, is observed using the FeS-H2S/FeS2 couple to provide the reducing power. We have used recent advances in theoretical geochemistry to estimate the standard partial moral thermodynamic properties and parameters for the revised Helgeson-Kirkham-Flowers equation of state for aqueous straight-chain alkyl thesis. With these data and parameters we have evaluated the role that organic sulfur compounds may play as reaction intermediates during organic compound synthesis. We conclude that organic sulfur compounds may hold the key to the organic chemistry leading to the origin of life in hydrothermal settings. These results may also explain the presence of sulfur in a number of biomolecules present in ancient thermophilic microorganisms.

Partial inertia induces additional phase transition in the majority vote model.

PubMed

Harunari, Pedro E; de Oliveira, M M; Fiore, C E

2017-10-01

Explosive (i.e., discontinuous) transitions have aroused great interest by manifesting in distinct systems, such as synchronization in coupled oscillators, percolation regime, absorbing phase transitions, and more recently, the majority-vote model with inertia. In the latter, the model rules are slightly modified by the inclusion of a term depending on the local spin (an inertial term). In such a case, Chen et al. [Phys Rev. E 95, 042304 (2017)2470-004510.1103/PhysRevE.95.042304] have found that relevant inertia changes the nature of the phase transition in complex networks, from continuous to discontinuous. Here we give a further step by embedding inertia only in vertices with degree larger than a threshold value 〈k〉k^{*}, 〈k〉 being the mean system degree and k^{*} the fraction restriction. Our results, from mean-field analysis and extensive numerical simulations, reveal that an explosive transition is presented in both homogeneous and heterogeneous structures for small and intermediate k^{*}'s. Otherwise, a large restriction can sustain a discontinuous transition only in the heterogeneous case. This shares some similarities with recent results for the Kuramoto model [Phys. Rev. E 91, 022818 (2015)PLEEE81539-375510.1103/PhysRevE.91.022818]. Surprisingly, intermediate restriction and large inertia are responsible for the emergence of an extra phase, in which the system is partially synchronized and the classification of phase transition depends on the inertia and the lattice topology. In this case, the system exhibits two phase transitions.

On the interrelation of multiplication and division in secondary school children.

PubMed

Huber, Stefan; Fischer, Ursula; Moeller, Korbinian; Nuerk, Hans-Christoph

2013-01-01

Each division problem can be transformed into as a multiplication problem and vice versa. Recent research has indicated strong developmental parallels between multiplication and division in primary school children. In this study, we were interested in (i) whether these developmental parallels persist into secondary school, (ii) whether similar developmental parallels can be observed for simple and complex problems, (iii) whether skill level modulates this relationship, and (iv) whether the correlations are specific and not driven by general cognitive or arithmetic abilities. Therefore, we assessed performance of 5th and 6th graders attending two secondary school types of the German educational system in simple and complex multiplication as well as division while controlling for non-verbal intelligence, short-term memory, and other arithmetic abilities. Accordingly, we collected data from students differing in skills levels due to either age (5th < 6th grade) or school type (general < intermediate secondary school). We observed moderate to strong bivariate and partial correlations between multiplication and division with correlations being higher for simple tasks but nevertheless reliable for complex tasks. Moreover, the association between simple multiplication and division depended on students' skill levels as reflected by school types, but not by age. Partial correlations were higher for intermediate than for general secondary school children. In sum, these findings emphasize the importance of the inverse relationship between multiplication and division which persists into later developmental stages. However, evidence for skill-related differences in the relationship between multiplication and division was restricted to the differences for school types.

A Naval Marksmanship Training Transfer Study: The Use of Indoor Simulated Marksmanship Trainers to Train for Live Fire

DTIC Science & Technology

2012-03-01

on the standard Navy Handgun Qualification Course. Results partially supported the hypotheses. The simulation group showed greater improvement in MPI...standard Navy Handgun Qualification Course. Results partially supported the hypotheses. The simulation group showed greater improvement in MPI than the...14 3. Navy Handgun Qualification Course Firing Sequence ..................15 F. PROCEDURES

Partially unzipped carbon nanotubes as a superior catalyst support for PEM fuel cells.

PubMed

Long, Donghui; Li, Wei; Qiao, Wenming; Miyawaki, Jin; Yoon, Seong-Ho; Mochida, Isao; Ling, Licheng

2011-09-07

Partially unzipped carbon nanotubes prepared by strong oxidation and thermal expansion of carbon nanotubes were explored as an advanced catalyst support for PEM fuel cells. The unique hybrid structure of 1D nanotube and 2D double-side graphene resulted in an outstanding electrocatalytic performance. This journal is © The Royal Society of Chemistry 2011

Molecular analysis of peroxisome proliferation in the hamster.

PubMed

Choudhury, Agharul I; Sims, Helen M; Horley, Neill J; Roberts, Ruth A; Tomlinson, Simon R; Salter, Andrew M; Bruce, Mary; Shaw, P Nicholas; Kendall, David; Barrett, David A; Bell, David R

2004-05-15

Three novel P450 members of the cytochrome P450 4A family were cloned as partial cDNAs from hamster liver, characterised as novel members of the CYP4A subfamily, and designated CYP4A17, 18, and 19. Hamsters were treated with the peroxisome proliferator-activated receptor alpha (PPARalpha) agonists, methylclofenapate (MCP) or Wy-14,643, and shown to develop hepatomegaly and induction of CYP4A17 RNA, and concomitant induction of lauric acid 12- hydroxylase. This treatment also resulted in hypolipidaemia, which was most pronounced in the VLDL fraction, with up to 50% reduction in VLDL-triglycerides; by contrast, blood cholesterol concentration was unaffected by this treatment. These data show that hamster is highly responsive to induction of CYP4A by peroxisome proliferators. To characterise the molecular basis of peroxisome proliferation, the hamster PPARalpha was cloned and shown to encode a 468-amino-acid protein, which is highly similar to rat and mouse PPARalpha proteins. The level of expression of hamster PPARalpha in liver is intermediate between mouse and guinea pig. These results fail to support the hypothesis that the level of PPARalpha in liver is directly responsible for species differences in peroxisome proliferation.

Numerical calculation of charge exchange cross sections for plasma diagnostics

NASA Astrophysics Data System (ADS)

Mendez, Luis

2016-09-01

The diagnostics of impurity density and temperature in the plasma core in tokamak plasmas is carried out by applying the charge exchange recombination spectroscopy (CXRS) technique, where a fast beam of H atoms collides with the plasma particles leading to electron capture reactions with the impurity ions. The diagnostics is based on the emission of the excited ions formed in the electron capture. The application of the CXRS requires the knowledge of accurate state-selective cross sections, which in general are not accessible experimentally, and the calculation of cross sections for the high n capture levels, required for the diagnostics in the intermediate energy domain of the probe beam, is particularly difficult. In this work, we present a lattice numerical method to solve the time dependent Schrödinger equation. The method is based on the GridTDSE package, it is applicable in the wide energy range 1 - 500 keV/u and can be used to assess the accuracy of previous calculations. The application of the method will be illustrated with calculations for collisions of multiply charged ions with H. Work partially supported by project ENE2014-52432-R (Secretaria de Estado de I+D+i, Spain).

Resveratrol and its oligomers from wine grapes are selective (1)O2 quenchers: mechanistic implication by high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry and theoretical calculation.

PubMed

Jiang, Li-Yan; He, Shan; Jiang, Ke-Zhi; Sun, Cui-Rong; Pan, Yuan-Jiang

2010-08-25

Resveratrol and its oligomers, abundantly present in wine grapes, are believed to be effective phytoalexins for the phenomenon "French paradox" partially by virtue of their powerful antiradical properties. EPR spin-trapping technique was utilized, demonstrating all polyphenols were selective (1)O2 quenchers but not effective (•)OH and O2(•¯) scavengers. On the basis of the HPLC-ESI-MS(2) analysis for the simulated reactions of polyphenols with (1)O2, the molecular weights of the resulting photochemical products were 14 or 28 Da higher than those of their substrates. No fragment C2H2O (42 Da), which was rather distinctive of the resorcinol rings in these cases, had been observed, whereas their MS/MS spectra displayed characteristic neutral fragments including carbon monoxide (CO, 28 Da) and 2-hydroxy[1,4]benzoquinone (C6H4O3, 124 Da). Finally, PM3 semiempirical calculations and HR-FTICR-MS experiments were performed, supporting the assertion that their quenching mechanism involved physical and chemical pathways. Chemical quenching underwent an endoperoxide intermediate form to generate quinones.

Keratin 1 maintains skin integrity and participates in an inflammatory network in skin through interleukin-18.

PubMed

Roth, Wera; Kumar, Vinod; Beer, Hans-Dietmar; Richter, Miriam; Wohlenberg, Claudia; Reuter, Ursula; Thiering, Sören; Staratschek-Jox, Andrea; Hofmann, Andrea; Kreusch, Fatima; Schultze, Joachim L; Vogl, Thomas; Roth, Johannes; Reichelt, Julia; Hausser, Ingrid; Magin, Thomas M

2012-11-15

Keratin 1 (KRT1) and its heterodimer partner keratin 10 (KRT10) are major constituents of the intermediate filament cytoskeleton in suprabasal epidermis. KRT1 mutations cause epidermolytic ichthyosis in humans, characterized by loss of barrier integrity and recurrent erythema. In search of the largely unknown pathomechanisms and the role of keratins in barrier formation and inflammation control, we show here that Krt1 is crucial for maintenance of skin integrity and participates in an inflammatory network in murine keratinocytes. Absence of Krt1 caused a prenatal increase in interleukin-18 (IL-18) and the S100A8 and S100A9 proteins, accompanied by a barrier defect and perinatal lethality. Depletion of IL-18 partially rescued Krt1(-/-) mice. IL-18 release was keratinocyte-autonomous, KRT1 and caspase-1 dependent, supporting an upstream role of KRT1 in the pathology. Finally, transcriptome profiling revealed a Krt1-mediated gene expression signature similar to atopic eczema and psoriasis, but different from Krt5 deficiency and epidermolysis bullosa simplex. Our data suggest a functional link between KRT1 and human inflammatory skin diseases.

Emotion recognition following early psychosocial deprivation

PubMed Central

Nelson, Charles A.; Westerlund, Alissa; McDermott, Jennifer Martin; Zeanah, Charles H.; Fox, Nathan A.

2014-01-01

We examined the ability to discriminate facial expressions among 8-year-old children who had been abandoned and placed in institutions in infancy and children with no institutional rearing (Never Institutionalized Group; NIG). Following a baseline assessment (average age=22 months), half the institutionalized children were randomly assigned to a foster care intervention (foster care group; FCG) and half to remain in the institution (care as usual group; CAUG). All three groups had a more difficult time recognizing fearful as compared to neutral expressions. However, the NIG and FCG were both better at inhibiting responses to neutral and fearful faces than the CAUG. Regarding ERPs, the P1 was biggest to angry faces for the NIG, smallest among the CAUG and intermediate for the FCG. The N170 and the P300 were biggest to fear in all groups. Although the children in foster care showed improvements in their ability to recognize fear and neutral faces, and their P1 to angry was midway between the NIG and CAUG, we observed no timing of placement effects. These findings support the view that institutional rearing leads to deficits in the ability to process facial emotion, and placement in foster care partially, although incompletely, ameliorates these deficits. PMID:23627960

Processes Modifying Cratered Terrains on Pluto

NASA Technical Reports Server (NTRS)

Moore, J. M.

2015-01-01

The July encounter with Pluto by the New Horizons spacecraft permitted imaging of its cratered terrains with scales as high as approximately 100 m/pixel, and in stereo. In the initial download of images, acquired at 2.2 km/pixel, widely distributed impact craters up to 260 km diameter are seen in the near-encounter hemisphere. Many of the craters appear to be significantly degraded or infilled. Some craters appear partially destroyed, perhaps by erosion such as associated with the retreat of scarps. Bright ice-rich deposits highlight some crater rims and/or floors. While the cratered terrains identified in the initial downloaded images are generally seen on high-to-intermediate albedo surfaces, the dark equatorial terrain informally known as Cthulhu Regio is also densely cratered. We will explore the range of possible processes that might have operated (or still be operating) to modify the landscape from that of an ancient pristinely cratered state to the present terrains revealed in New Horizons images. The sequence, intensity, and type of processes that have modified ancient landscapes are, among other things, the record of climate and volatile evolution throughout much of the Pluto's existence. The deciphering of this record will be discussed. This work was supported by NASA's New Horizons project.

Source localization of non-stationary acoustic data using time-frequency analysis

NASA Astrophysics Data System (ADS)

Stoughton, Jack; Edmonson, William

2005-04-01

An improvement in temporal locality of the generalized cross-correlation (GCC) for angle of arrival (AOA) estimation can be achieved by employing 2-D cross-correlation of infrasonic sensor data transformed to its time-frequency (TF) representation. Intermediate to the AOA evaluation is the time delay between pairs of sensors. The signal class of interest includes far field sources which are partially coherent across the array, nonstationary, and wideband. In addition, signals can occur as multiple short bursts, for which TF representations may be more appropriate for time delay estimation. The GCC tends to smooth out such temporal energy bursts. Simulation and experimental results will demonstrate the improvement in using a TF-based GCC, using the Cohen class, over the classic GCC method. Comparative demonstration of the methods will be performed on data captured on an infrasonic sensor array located at NASA Langley Research Center (LaRC). The infrasonic data sources include Delta IV and Space Shuttle launches from Kennedy Space Center which belong to the stated signal class. Of interest is to apply this method to the AOA estimation of atmospheric turbulence. [Work supported by NASA LaRC Creativity and Innovation project: Infrasonic Detection of Clear Air Turbulence and Severe Storms.

Learning physical biology via modeling and simulation: A new course and textbook for science and engineering undergraduates

NASA Astrophysics Data System (ADS)

Nelson, Philip

To a large extent, undergraduate physical-science curricula remain firmly rooted in pencil-and-paper calculation, despite the fact that most research is done with computers. To a large extent, undergraduate life-science curricula remain firmly rooted in descriptive approaches, despite the fact that much current research involves quantitative modeling. Not only does our pedagogy not reflect current reality; it also creates a spurious barrier between the fields, reinforcing the narrow silos that prevent students from connecting them. I'll describe an intermediate-level course on ``Physical Models of Living Systems.'' The prerequisite is first-year university physics and calculus. The course is a response to rapidly growing interest among undergraduates in a broad range of science and engineering majors. Students acquire several research skills that are often not addressed in traditional undergraduate courses: •Basic modeling skills; •Probabilistic modeling skills; •Data analysis methods; •Computer programming using a general-purpose platform like MATLAB or Python; •Pulling datasets from the Web for analysis; •Data visualization; •Dynamical systems, particularly feedback control. Partially supported by the NSF under Grants EF-0928048 and DMR-0832802.

Analysis of the process of representing clinical statements for decision-support applications: a comparison of openEHR archetypes and HL7 virtual medical record.

PubMed

González-Ferrer, A; Peleg, M; Marcos, M; Maldonado, J A

2016-07-01

Delivering patient-specific decision-support based on computer-interpretable guidelines (CIGs) requires mapping CIG clinical statements (data items, clinical recommendations) into patients' data. This is most effectively done via intermediate data schemas, which enable querying the data according to the semantics of a shared standard intermediate schema. This study aims to evaluate the use of HL7 virtual medical record (vMR) and openEHR archetypes as intermediate schemas for capturing clinical statements from CIGs that are mappable to electronic health records (EHRs) containing patient data and patient-specific recommendations. Using qualitative research methods, we analyzed the encoding of ten representative clinical statements taken from two CIGs used in real decision-support systems into two health information models (openEHR archetypes and HL7 vMR instances) by four experienced informaticians. Discussion among the modelers about each case study example greatly increased our understanding of the capabilities of these standards, which we share in this educational paper. Differing in content and structure, the openEHR archetypes were found to contain a greater level of representational detail and structure while the vMR representations took fewer steps to complete. The use of openEHR in the encoding of CIG clinical statements could potentially facilitate applications other than decision-support, including intelligent data analysis and integration of additional properties of data items from existing EHRs. On the other hand, due to their smaller size and fewer details, the use of vMR potentially supports quicker mapping of EHR data into clinical statements.

Electrochemical Behavior of TiO(x)C(y) as Catalyst Support for Direct Ethanol Fuel Cells at Intermediate Temperature: From Planar Systems to Powders.

PubMed

Calvillo, Laura; García, Gonzalo; Paduano, Andrea; Guillen-Villafuerte, Olmedo; Valero-Vidal, Carlos; Vittadini, Andrea; Bellini, Marco; Lavacchi, Alessandro; Agnoli, Stefano; Martucci, Alessandro; Kunze-Liebhäuser, Julia; Pastor, Elena; Granozzi, Gaetano

2016-01-13

To achieve complete oxidation of ethanol (EOR) to CO2, higher operating temperatures (often called intermediate-T, 150-200 °C) and appropriate catalysts are required. We examine here titanium oxycarbide (hereafter TiOxCy) as a possible alternative to standard carbon-based supports to enhance the stability of the catalyst/support assembly at intermediate-T. To test this material as electrocatalyst support, a systematic study of its behavior under electrochemical conditions was carried out. To have a clear description of the chemical changes of TiOxCy induced by electrochemical polarization of the material, a special setup that allows the combination of X-ray photoelectron spectroscopy and electrochemical measurements was used. Subsequently, an electrochemical study was carried out on TiOxCy powders, both at room temperature and at 150 °C. The present study has revealed that TiOxCy is a sufficiently conductive material whose surface is passivated by a TiO2 film under working conditions, which prevents the full oxidation of the TiOxCy and can thus be considered a stable electrode material for EOR working conditions. This result has also been confirmed through density functional theory (DFT) calculations on a simplified model system. Furthermore, it has been experimentally observed that ethanol molecules adsorb on the TiOxCy surface, inhibiting its oxidation. This result has been confirmed by using in situ Fourier transform infrared spectroscopy (FTIRS). The adsorption of ethanol is expected to favor the EOR in the presence of suitable catalyst nanoparticles supported on TiOxCy.

Partitioning of V, Mn, Co, Ni, Cu, Zn, As, Mo, Ag, Sn, Sb, W, Au, Pb, and Bi between sulfide phases and hydrous basanite melt at upper mantle conditions

NASA Astrophysics Data System (ADS)

Li, Yuan; Audétat, Andreas

2012-11-01

The partitioning of 15 major to trace metals between monosulfide solid solution (MSS), sulfide liquid (SL) and mafic silicate melt (SM) was determined in piston-cylinder experiments performed at 1175-1300 °C, 1.5-3.0 GPa and oxygen fugacities ranging from 3.1 log units below to 1.0 log units above the quartz-fayalite-magnetite fO2 buffer, which conditions are representative of partial melting in the upper mantle in different tectonic settings. The silicate melt was produced by partial melting of a natural, amphibole-rich mantle source rock, resulting in hydrous (˜5 wt% H2O) basanitic melts similar to low-degree partial melts of metasomatized mantle, whereas the major element composition of the starting sulfide (˜52 wt% Fe; 39 wt% S; 7 wt% Ni; 2 wt% Cu) was similar to the average composition of sulfides in this environment. SL/SM partition coefficients are high (≥100) for Au, Ni, Cu, Ag, Bi, intermediate (1-100) for Co, Pb, Sn, Sb (±As, Mo), and low (≤1) for the remaining elements. MSS/SM partition coefficients are generally lower than SL/SM partition coefficients and are high (≥100) for Ni, Cu, Au, intermediate (1-100) for Co, Ag (±Bi, Mo), and low (≤1) for the remaining elements. Most sulfide-silicate melt partition coefficients vary as a function of fO2, with Mo, Bi, As (±W) varying by a factor >10 over the investigated fO2 range, Sb, Ag, Sn (±V) varying by a factor of 3-10, and Pb, Cu, Ni, Co, Au, Zn, Mn varying by a factor of 3-10. The partitioning data were used to model the behavior of Cu, Au, Ag, and Bi during partial melting of upper mantle and during fractional crystallization of primitive MORB and arc magmas. Sulfide phase relationships and comparison of the modeling results with reported Cu, Au, Ag, and Bi concentrations from MORB and arc magmas suggest that: (i) MSS is the dominant sulfide in the source region of arc magmas, and thus that Au/Cu ratios in the silicate melt and residual sulfides may decrease with increasing degree of partial melting, (ii) both MSS and sulfide liquid are precipitated during fractional crystallization of MORB, and (iii) fractional crystallization of arc magmas is strongly dominated by MSS.

Design and Implementation of an Intelligent Cost Estimation Model for Decision Support System Software

DTIC Science & Technology

1990-09-01

following two chapters. 28 V. COCOMO MODEL A. OVERVIEW The COCOMO model which stands for COnstructive COst MOdel was developed by Barry Boehm and is...estimation model which uses an expert system to automate the Intermediate COnstructive Cost Estimation MOdel (COCOMO), developed by Barry W. Boehm and...cost estimation model which uses an expert system to automate the Intermediate COnstructive Cost Estimation MOdel (COCOMO), developed by Barry W

Tuning and Freezing Disorder in Photonic Crystals using Percolation Lithography.

PubMed

Burgess, Ian B; Abedzadeh, Navid; Kay, Theresa M; Shneidman, Anna V; Cranshaw, Derek J; Lončar, Marko; Aizenberg, Joanna

2016-01-21

Although common in biological systems, synthetic self-assembly routes to complex 3D photonic structures with tailored degrees of disorder remain elusive. Here we show how liquids can be used to finely control disorder in porous 3D photonic crystals, leading to complex and hierarchical geometries. In these optofluidic crystals, dynamically tunable disorder is superimposed onto the periodic optical structure through partial wetting or evaporation. In both cases, macroscopic symmetry breaking is driven by subtle sub-wavelength variations in the pore geometry. These variations direct site-selective infiltration of liquids through capillary interactions. Incorporating cross-linkable resins into our liquids, we developed methods to freeze in place the filling patterns at arbitrary degrees of partial wetting and intermediate stages of drying. These percolation lithography techniques produced permanent photonic structures with adjustable disorder. By coupling strong changes in optical properties to subtle differences in fluid behavior, optofluidic crystals may also prove useful in rapid analysis of liquids.

Validation of a partial coherence interferometry method for estimating retinal shape

PubMed Central

Verkicharla, Pavan K.; Suheimat, Marwan; Pope, James M.; Sepehrband, Farshid; Mathur, Ankit; Schmid, Katrina L.; Atchison, David A.

2015-01-01

To validate a simple partial coherence interferometry (PCI) based retinal shape method, estimates of retinal shape were determined in 60 young adults using off-axis PCI, with three stages of modeling using variants of the Le Grand model eye, and magnetic resonance imaging (MRI). Stage 1 and 2 involved a basic model eye without and with surface ray deviation, respectively and Stage 3 used model with individual ocular biometry and ray deviation at surfaces. Considering the theoretical uncertainty of MRI (12-14%), the results of the study indicate good agreement between MRI and all three stages of PCI modeling with <4% and <7% differences in retinal shapes along horizontal and vertical meridians, respectively. Stage 2 and Stage 3 gave slightly different retinal co-ordinates than Stage 1 and we recommend the intermediate Stage 2 as providing a simple and valid method of determining retinal shape from PCI data. PMID:26417496

Validation of a partial coherence interferometry method for estimating retinal shape.

PubMed

Verkicharla, Pavan K; Suheimat, Marwan; Pope, James M; Sepehrband, Farshid; Mathur, Ankit; Schmid, Katrina L; Atchison, David A

2015-09-01

To validate a simple partial coherence interferometry (PCI) based retinal shape method, estimates of retinal shape were determined in 60 young adults using off-axis PCI, with three stages of modeling using variants of the Le Grand model eye, and magnetic resonance imaging (MRI). Stage 1 and 2 involved a basic model eye without and with surface ray deviation, respectively and Stage 3 used model with individual ocular biometry and ray deviation at surfaces. Considering the theoretical uncertainty of MRI (12-14%), the results of the study indicate good agreement between MRI and all three stages of PCI modeling with <4% and <7% differences in retinal shapes along horizontal and vertical meridians, respectively. Stage 2 and Stage 3 gave slightly different retinal co-ordinates than Stage 1 and we recommend the intermediate Stage 2 as providing a simple and valid method of determining retinal shape from PCI data.

Aldehydes in hydrothermal solution - Standard partial molal thermodynamic properties and relative stabilities at high temperatures and pressures

NASA Technical Reports Server (NTRS)

Schulte, Mitchell D.; Shock, Everett L.

1993-01-01

Aldehydes are common in a variety of geologic environments and are derived from a number of sources, both natural and anthropogenic. Experimental data for aqueous aldehydes were taken from the literature and used, along with parameters for the revised Helgeson-Kirkham-Flowers (HKF) equations of state, to estimate standard partial molal thermodynamic data for aqueous straight-chain alkyl aldehydes at high temperatures and pressures. Examples of calculations involving aldehydes in geological environments are given, and the stability of aldehydes relative to carboxylic acids is evaluated. These calculations indicate that aldehydes may be intermediates in the formation of carboxylic acids from hydrocarbons in sedimentary basin brines and hydrothermal systems like they are in the atmosphere. The data and parameters summarized here allow evaluation of the role of aldehydes in the formation of prebiotic precursors, such as amino acids and hydroxy acids on the early Earth and in carbonaceous chondrite parent bodies.

Characterization of sympatric Platanthera bifolia and Platanthera chlorantha (Orchidaceae) populations with intermediate plants.

PubMed

Esposito, Fabiana; Vereecken, Nicolas J; Gammella, Maddalena; Rinaldi, Rosita; Laurent, Pascal; Tyteca, Daniel

2018-01-01

Platanthera bifolia and P. chlorantha are terrestrial and rewarding orchids with a wide Eurasian distribution. Although genetically closely related, they exhibit significant morphological, phenological and ecological differences that maintain reproductive isolation between the species. However, where both species co-occur, individuals with intermediate phenotypic traits, often considered as hybrids, are frequently observed. Here, we combined neutral genetic markers (AFLPs), morphometrics and floral scent analysis (GC-MS) to investigate two mixed Platanthera populations where morphologically intermediate plants were found. Self-pollination experiments revealed a low level of autogamy and artificial crossings combined with assessments of fruit set and seed viability, showed compatibility between the two species. The results of the genetic analyses showed that morphologically intermediate plants had similar genetic patterns as the P. bifolia group. These results are corroborated also by floral scent analyses, which confirmed a strong similarity in floral scent composition between intermediate morphotypes and P. bifolia . Therefore, this study provided a much more detailed picture of the genetic structure of a sympatric zone between two closely allied species and supports the hypothesis that intermediate morphotypes in sympatry could reflect an adaptive evolution in response to local pollinator-mediated selection.

Caenorhabditis elegans HIM-18/SLX-4 interacts with SLX-1 and XPF-1 and maintains genomic integrity in the germline by processing recombination intermediates.

PubMed

Saito, Takamune T; Youds, Jillian L; Boulton, Simon J; Colaiácovo, Monica P

2009-11-01

Homologous recombination (HR) is essential for the repair of blocked or collapsed replication forks and for the production of crossovers between homologs that promote accurate meiotic chromosome segregation. Here, we identify HIM-18, an ortholog of MUS312/Slx4, as a critical player required in vivo for processing late HR intermediates in Caenorhabditis elegans. DNA damage sensitivity and an accumulation of HR intermediates (RAD-51 foci) during premeiotic entry suggest that HIM-18 is required for HR-mediated repair at stalled replication forks. A reduction in crossover recombination frequencies-accompanied by an increase in HR intermediates during meiosis, germ cell apoptosis, unstable bivalent attachments, and subsequent chromosome nondisjunction-support a role for HIM-18 in converting HR intermediates into crossover products. Such a role is suggested by physical interaction of HIM-18 with the nucleases SLX-1 and XPF-1 and by the synthetic lethality of him-18 with him-6, the C. elegans BLM homolog. We propose that HIM-18 facilitates processing of HR intermediates resulting from replication fork collapse and programmed meiotic DSBs in the C. elegans germline.

Caenorhabditis elegans HIM-18/SLX-4 Interacts with SLX-1 and XPF-1 and Maintains Genomic Integrity in the Germline by Processing Recombination Intermediates

PubMed Central

Saito, Takamune T.; Youds, Jillian L.; Boulton, Simon J.; Colaiácovo, Monica P.

2009-01-01

Homologous recombination (HR) is essential for the repair of blocked or collapsed replication forks and for the production of crossovers between homologs that promote accurate meiotic chromosome segregation. Here, we identify HIM-18, an ortholog of MUS312/Slx4, as a critical player required in vivo for processing late HR intermediates in Caenorhabditis elegans. DNA damage sensitivity and an accumulation of HR intermediates (RAD-51 foci) during premeiotic entry suggest that HIM-18 is required for HR–mediated repair at stalled replication forks. A reduction in crossover recombination frequencies—accompanied by an increase in HR intermediates during meiosis, germ cell apoptosis, unstable bivalent attachments, and subsequent chromosome nondisjunction—support a role for HIM-18 in converting HR intermediates into crossover products. Such a role is suggested by physical interaction of HIM-18 with the nucleases SLX-1 and XPF-1 and by the synthetic lethality of him-18 with him-6, the C. elegans BLM homolog. We propose that HIM-18 facilitates processing of HR intermediates resulting from replication fork collapse and programmed meiotic DSBs in the C. elegans germline. PMID:19936019

Explaining local-scale species distributions: relative contributions of spatial autocorrelation and landscape heterogeneity for an avian assemblage

USGS Publications Warehouse

Mattsson, Brady J.; Zipkin, Elise F.; Gardner, Beth; Blank, Peter J.; Sauer, John R.; Royle, J. Andrew

2013-01-01

Understanding interactions between mobile species distributions and landcover characteristics remains an outstanding challenge in ecology. Multiple factors could explain species distributions including endogenous evolutionary traits leading to conspecific clustering and endogenous habitat features that support life history requirements. Birds are a useful taxon for examining hypotheses about the relative importance of these factors among species in a community. We developed a hierarchical Bayes approach to model the relationships between bird species occupancy and local landcover variables accounting for spatial autocorrelation, species similarities, and partial observability. We fit alternative occupancy models to detections of 90 bird species observed during repeat visits to 316 point-counts forming a 400-m grid throughout the Patuxent Wildlife Research Refuge in Maryland, USA. Models with landcover variables performed significantly better than our autologistic and null models, supporting the hypothesis that local landcover heterogeneity is important as an exogenous driver for species distributions. Conspecific clustering alone was a comparatively poor descriptor of local community composition, but there was evidence for spatial autocorrelation in all species. Considerable uncertainty remains whether landcover combined with spatial autocorrelation is most parsimonious for describing bird species distributions at a local scale. Spatial structuring may be weaker at intermediate scales within which dispersal is less frequent, information flows are localized, and landcover types become spatially diversified and therefore exhibit little aggregation. Examining such hypotheses across species assemblages contributes to our understanding of community-level associations with conspecifics and landscape composition.

Explaining local-scale species distributions: relative contributions of spatial autocorrelation and landscape heterogeneity for an avian assemblage.

PubMed

Mattsson, Brady J; Zipkin, Elise F; Gardner, Beth; Blank, Peter J; Sauer, John R; Royle, J Andrew

2013-01-01

Understanding interactions between mobile species distributions and landcover characteristics remains an outstanding challenge in ecology. Multiple factors could explain species distributions including endogenous evolutionary traits leading to conspecific clustering and endogenous habitat features that support life history requirements. Birds are a useful taxon for examining hypotheses about the relative importance of these factors among species in a community. We developed a hierarchical Bayes approach to model the relationships between bird species occupancy and local landcover variables accounting for spatial autocorrelation, species similarities, and partial observability. We fit alternative occupancy models to detections of 90 bird species observed during repeat visits to 316 point-counts forming a 400-m grid throughout the Patuxent Wildlife Research Refuge in Maryland, USA. Models with landcover variables performed significantly better than our autologistic and null models, supporting the hypothesis that local landcover heterogeneity is important as an exogenous driver for species distributions. Conspecific clustering alone was a comparatively poor descriptor of local community composition, but there was evidence for spatial autocorrelation in all species. Considerable uncertainty remains whether landcover combined with spatial autocorrelation is most parsimonious for describing bird species distributions at a local scale. Spatial structuring may be weaker at intermediate scales within which dispersal is less frequent, information flows are localized, and landcover types become spatially diversified and therefore exhibit little aggregation. Examining such hypotheses across species assemblages contributes to our understanding of community-level associations with conspecifics and landscape composition.

Explaining Local-Scale Species Distributions: Relative Contributions of Spatial Autocorrelation and Landscape Heterogeneity for an Avian Assemblage

PubMed Central

Mattsson, Brady J.; Zipkin, Elise F.; Gardner, Beth; Blank, Peter J.; Sauer, John R.; Royle, J. Andrew

2013-01-01

Understanding interactions between mobile species distributions and landcover characteristics remains an outstanding challenge in ecology. Multiple factors could explain species distributions including endogenous evolutionary traits leading to conspecific clustering and endogenous habitat features that support life history requirements. Birds are a useful taxon for examining hypotheses about the relative importance of these factors among species in a community. We developed a hierarchical Bayes approach to model the relationships between bird species occupancy and local landcover variables accounting for spatial autocorrelation, species similarities, and partial observability. We fit alternative occupancy models to detections of 90 bird species observed during repeat visits to 316 point-counts forming a 400-m grid throughout the Patuxent Wildlife Research Refuge in Maryland, USA. Models with landcover variables performed significantly better than our autologistic and null models, supporting the hypothesis that local landcover heterogeneity is important as an exogenous driver for species distributions. Conspecific clustering alone was a comparatively poor descriptor of local community composition, but there was evidence for spatial autocorrelation in all species. Considerable uncertainty remains whether landcover combined with spatial autocorrelation is most parsimonious for describing bird species distributions at a local scale. Spatial structuring may be weaker at intermediate scales within which dispersal is less frequent, information flows are localized, and landcover types become spatially diversified and therefore exhibit little aggregation. Examining such hypotheses across species assemblages contributes to our understanding of community-level associations with conspecifics and landscape composition. PMID:23393564

Partial Support Ventilation and Mitochondrial-Targeted Antioxidants Protect against Ventilator-Induced Decreases in Diaphragm Muscle Protein Synthesis.

PubMed

Hudson, Matthew B; Smuder, Ashley J; Nelson, W Bradley; Wiggs, Michael P; Shimkus, Kevin L; Fluckey, James D; Szeto, Hazel H; Powers, Scott K

2015-01-01

Mechanical ventilation (MV) is a life-saving intervention in patients in respiratory failure. Unfortunately, prolonged MV results in the rapid development of diaphragm atrophy and weakness. MV-induced diaphragmatic weakness is significant because inspiratory muscle dysfunction is a risk factor for problematic weaning from MV. Therefore, developing a clinical intervention to prevent MV-induced diaphragm atrophy is important. In this regard, MV-induced diaphragmatic atrophy occurs due to both increased proteolysis and decreased protein synthesis. While efforts to impede MV-induced increased proteolysis in the diaphragm are well-documented, only one study has investigated methods of preserving diaphragmatic protein synthesis during prolonged MV. Therefore, we evaluated the efficacy of two therapeutic interventions that, conceptually, have the potential to sustain protein synthesis in the rat diaphragm during prolonged MV. Specifically, these experiments were designed to: 1) determine if partial-support MV will protect against the decrease in diaphragmatic protein synthesis that occurs during prolonged full-support MV; and 2) establish if treatment with a mitochondrial-targeted antioxidant will maintain diaphragm protein synthesis during full-support MV. Compared to spontaneously breathing animals, full support MV resulted in a significant decline in diaphragmatic protein synthesis during 12 hours of MV. In contrast, diaphragm protein synthesis rates were maintained during partial support MV at levels comparable to spontaneous breathing animals. Further, treatment of animals with a mitochondrial-targeted antioxidant prevented oxidative stress during full support MV and maintained diaphragm protein synthesis at the level of spontaneous breathing animals. We conclude that treatment with mitochondrial-targeted antioxidants or the use of partial-support MV are potential strategies to preserve diaphragm protein synthesis during prolonged MV.

Structural Characterization of a Human-Type Corrinoid Adenosyltransferase Confirms That Coenzyme B[subscript 12] Is Synthesized through a Four-Coordinate Intermediate

DOE Office of Scientific and Technical Information (OSTI.GOV)

St. Maurice, Martin; Mera, Paola; Park, Kiyoung

ATP:cob(I)alamin adenosyltransferases (ACAs) catalyze the transfer of the 5{prime}-deoxyadenosyl moiety from ATP to the upper axial ligand position of cobalamin in the synthesis of coenzyme B{sub 12}. For the ACA-catalyzed reaction to proceed, cob(II)alamin must be reduced to cob(I)alamin in the enzyme active site. This reduction is facilitated through the generation of a four-coordinate cob(II)alamin intermediate on the enzyme. We have determined the high-resolution crystal structure of a human-type ACA from Lactobacillus reuteri with a four-coordinate cob(II)alamin bound in the enzyme active site and with the product, adenosylcobalamin, partially occupied in the active site. The assembled structures represent snapshots ofmore » the steps in the ACA-catalyzed formation of the cobalt-carbon bond of coenzyme B{sub 12}. The structures define the corrinoid binding site and provide visual evidence for a base-off, four-coordinate cob(II)alamin intermediate. The complete structural description of ACA-mediated catalysis reveals the molecular features of four-coordinate cob(II)alamin stabilization and provides additional insights into the molecular basis for dysfunction in human patients suffering from methylmalonic aciduria.« less

Estimating the atmospheric concentration of Criegee intermediates and their possible interference in a FAGE-LIF instrument

NASA Astrophysics Data System (ADS)

Novelli, Anna; Hens, Korbinian; Tatum Ernest, Cheryl; Martinez, Monica; Nölscher, Anke C.; Sinha, Vinayak; Paasonen, Pauli; Petäjä, Tuukka; Sipilä, Mikko; Elste, Thomas; Plass-Dülmer, Christian; Phillips, Gavin J.; Kubistin, Dagmar; Williams, Jonathan; Vereecken, Luc; Lelieveld, Jos; Harder, Hartwig

2017-06-01

We analysed the extensive dataset from the HUMPPA-COPEC 2010 and the HOPE 2012 field campaigns in the boreal forest and rural environments of Finland and Germany, respectively, and estimated the abundance of stabilised Criegee intermediates (SCIs) in the lower troposphere. Based on laboratory tests, we propose that the background OH signal observed in our IPI-LIF-FAGE instrument during the aforementioned campaigns is caused at least partially by SCIs. This hypothesis is based on observed correlations with temperature and with concentrations of unsaturated volatile organic compounds and ozone. Just like SCIs, the background OH concentration can be removed through the addition of sulfur dioxide. SCIs also add to the previously underestimated production rate of sulfuric acid. An average estimate of the SCI concentration of ˜ 5.0 × 104 molecules cm-3 (with an order of magnitude uncertainty) is calculated for the two environments. This implies a very low ambient concentration of SCIs, though, over the boreal forest, significant for the conversion of SO2 into H2SO4. The large uncertainties in these calculations, owing to the many unknowns in the chemistry of Criegee intermediates, emphasise the need to better understand these processes and their potential effect on the self-cleaning capacity of the atmosphere.

Pauling and Corey's alpha-pleated sheet structure may define the prefibrillar amyloidogenic intermediate in amyloid disease.

PubMed

Armen, Roger S; DeMarco, Mari L; Alonso, Darwin O V; Daggett, Valerie

2004-08-10

Transthyretin, beta(2)-microglobulin, lysozyme, and the prion protein are four of the best-characterized proteins implicated in amyloid disease. Upon partial acid denaturation, these proteins undergo conformational change into an amyloidogenic intermediate that can self-assemble into amyloid fibrils. Many experiments have shown that pH-mediated changes in structure are required for the formation of the amyloidogeneic intermediate, but it has proved impossible to characterize these conformational changes at high resolution using experimental means. To probe these conformational changes at atomic resolution, we have performed molecular dynamics simulations of these proteins at neutral and low pH. In low-pH simulations of all four proteins, we observe the formation of alpha-pleated sheet secondary structure, which was first proposed by L. Pauling and R. B. Corey [(1951) Proc. Natl. Acad. Sci. USA 37, 251-256]. In all beta-sheet proteins, transthyretin and beta(2)-microglobulin, alpha-pleated sheet structure formed over the strands that are highly protected in hydrogen-exchange experiments probing amyloidogenic conditions. In lysozyme and the prion protein, alpha-sheets formed in the specific regions of the protein implicated in the amyloidogenic conversion. We propose that the formation of alpha-pleated sheet structure may be a common conformational transition in amyloidosis.

Pauling and Corey's α-pleated sheet structure may define the prefibrillar amyloidogenic intermediate in amyloid disease

PubMed Central

Armen, Roger S.; DeMarco, Mari L.; Alonso, Darwin O. V.; Daggett, Valerie

2004-01-01

Transthyretin, β2-microglobulin, lysozyme, and the prion protein are four of the best-characterized proteins implicated in amyloid disease. Upon partial acid denaturation, these proteins undergo conformational change into an amyloidogenic intermediate that can self-assemble into amyloid fibrils. Many experiments have shown that pH-mediated changes in structure are required for the formation of the amyloidogeneic intermediate, but it has proved impossible to characterize these conformational changes at high resolution using experimental means. To probe these conformational changes at atomic resolution, we have performed molecular dynamics simulations of these proteins at neutral and low pH. In low-pH simulations of all four proteins, we observe the formation of α-pleated sheet secondary structure, which was first proposed by L. Pauling and R. B. Corey [(1951) Proc. Natl. Acad. Sci. USA 37, 251–256]. In all β-sheet proteins, transthyretin and β2-microglobulin, α-pleated sheet structure formed over the strands that are highly protected in hydrogen-exchange experiments probing amyloidogenic conditions. In lysozyme and the prion protein, α-sheets formed in the specific regions of the protein implicated in the amyloidogenic conversion. We propose that the formation of α-pleated sheet structure may be a common conformational transition in amyloidosis. PMID:15280548

Understanding and Mitigating the Effects of Stable Dodecahydro- closo -dodecaborate Intermediates on Hydrogen-Storage Reactions

DOE PAGES

White, James L.; Newhouse, Rebecca J.; Zhang, Jin Z.; ...

2016-10-25

Alkali metal borohydrides can reversibly store hydrogen; however, the materials display poor cyclability, often times linked to occurrence of stable closo-polyborate intermediate species. In an effort to understand the role of such intermediates on the hydrogen storage properties of metal borohydrides, several alkali metal dodecahydro-closo-dodecaborate salts were isolated in anhydrous form and characterized by diffraction and spectroscopic techniques. Mixtures of Li 2B 12H 12, Na 2B 12H 12, and K 2B 12H 12 with the corresponding alkali metal hydrides were subjected to hydrogenation conditions known to favor partial or full reversibility in metal borohydrides. The stoichiometric mixtures of MH andmore » M 2B 12H 12 salts form the corresponding metal borohydrides MBH 4 (M=Li, Na, K) in almost quantitative yield at 100 MPa H 2 and 500 °C. In addition, stoichiometric mixtures of Li 2B 12H 12 and MgH 2 were found to form MgB 2 at 500 °C and above upon desorption in vacuum. The two destabilization strategies outlined above suggest that metal polyhydro-closo-polyborate species can be converted into the corresponding metal borohydrides or borides, albeit under rather harsh conditions of hydrogen pressure and temperature.« less

The Structure of a High Fidelity DNA Polymerase Bound to a Mismatched Nucleotide Reveals an “Ajar” Intermediate Conformation in the Nucleotide Selection Mechanism*

PubMed Central

Wu, Eugene Y.; Beese, Lorena S.

2011-01-01

To achieve accurate DNA synthesis, DNA polymerases must rapidly sample and discriminate against incorrect nucleotides. Here we report the crystal structure of a high fidelity DNA polymerase I bound to DNA primer-template caught in the act of binding a mismatched (dG:dTTP) nucleoside triphosphate. The polymerase adopts a conformation in between the previously established “open” and “closed” states. In this “ajar” conformation, the template base has moved into the insertion site but misaligns an incorrect nucleotide relative to the primer terminus. The displacement of a conserved active site tyrosine in the insertion site by the template base is accommodated by a distinctive kink in the polymerase O helix, resulting in a partially open ternary complex. We suggest that the ajar conformation allows the template to probe incoming nucleotides for complementarity before closure of the enzyme around the substrate. Based on solution fluorescence, kinetics, and crystallographic analyses of wild-type and mutant polymerases reported here, we present a three-state reaction pathway in which nucleotides either pass through this intermediate conformation to the closed conformation and catalysis or are misaligned within the intermediate, leading to destabilization of the closed conformation. PMID:21454515

Treadmill Training with Partial Body-Weight Support in Children with Cerebral Palsy: A Systematic Review

ERIC Educational Resources Information Center

Mutlu, Akmer; Krosschell, Kristin; Spira, Deborah Gaebler

2009-01-01

OKAim: The aim of this systematic review was to examine the literature on the effects of partial body-weight support treadmill training (PBWSTT) in children with cerebral palsy (CP) on functional outcomes and attainment of ambulation. Method: We searched the relevant literature from 1950 to July 2007. We found eight studies on the use of PWSBTT on…

Involving older people in intermediate care.

PubMed

Andrews, JoyAnn; Manthorpe, Jill; Watson, Roger

2004-05-01

Intermediate care has become a crucial part of the United Kingdom government's programme for improving services for older people. Older people comprise a substantial part of the user base for these services, and it is increasingly recognized that there is a need for greater user involvement in service development for intermediate care. National initiatives undertaken in intermediate care have sought to widen and deepen the remit of such services, and in this way promote greater independence and improved quality of care for older people. In particular, the government has set out clear plans for reshaping services for older people in the National Health Service Plan and the rationale for greater involvement of older people in service development. This article considers ways in which these national and local objectives may be achieved and considers some of the implications for nursing. This paper aims to explore the concept of intermediate care and to identify trends and existing evidence of user involvement in care. In this way it charts a possible way forward for the development of a more 'user sensitive' approach. The following databases were searched: Medline, Cochrane Library, the Social Science Citation Index and CINAHL. Key words were 'intermediate care', 'older people', 'formal care', 'primary care', 'social services' and 'geriatrics', used in combination. The findings from this study indicate that there is considerable scope for increased user involvement in service development for intermediate care. Such challenges may be more effectively met through greater clarity of the concept of intermediate care, and a bridging of user involvement at the practice and policy levels. Nurses are key providers of intermediate care in the community. The involvement of older people in intermediate care service development must be premised on a shared comprehension of the purpose and function of intermediate care. Nurses must be involved in shifting intermediate care from being service-focused to patient-centred. Effective participation eschews the application of global constructs for older people, while supporting greater participation at all levels and robust implementation processes.

Factors associated with blood oxygen partial pressure and carbon dioxide partial pressure regulation during respiratory extracorporeal membrane oxygenation support: data from a swine model.

PubMed

Park, Marcelo; Mendes, Pedro Vitale; Costa, Eduardo Leite Vieira; Barbosa, Edzangela Vasconcelos Santos; Hirota, Adriana Sayuri; Azevedo, Luciano Cesar Pontes

2016-01-01

The aim of this study was to explore the factors associated with blood oxygen partial pressure and carbon dioxide partial pressure. The factors associated with oxygen - and carbon dioxide regulation were investigated in an apneic pig model under veno-venous extracorporeal membrane oxygenation support. A predefined sequence of blood and sweep flows was tested. Oxygenation was mainly associated with extracorporeal membrane oxygenation blood flow (beta coefficient = 0.036mmHg/mL/min), cardiac output (beta coefficient = -11.970mmHg/L/min) and pulmonary shunting (beta coefficient = -0.232mmHg/%). Furthermore, the initial oxygen partial pressure and carbon dioxide partial pressure measurements were also associated with oxygenation, with beta coefficients of 0.160 and 0.442mmHg/mmHg, respectively. Carbon dioxide partial pressure was associated with cardiac output (beta coefficient = 3.578mmHg/L/min), sweep gas flow (beta coefficient = -2.635mmHg/L/min), temperature (beta coefficient = 4.514mmHg/ºC), initial pH (beta coefficient = -66.065mmHg/0.01 unit) and hemoglobin (beta coefficient = 6.635mmHg/g/dL). In conclusion, elevations in blood and sweep gas flows in an apneic veno-venous extracorporeal membrane oxygenation model resulted in an increase in oxygen partial pressure and a reduction in carbon dioxide partial pressure 2, respectively. Furthermore, without the possibility of causal inference, oxygen partial pressure was negatively associated with pulmonary shunting and cardiac output, and carbon dioxide partial pressure was positively associated with cardiac output, core temperature and initial hemoglobin.

Hybrid songbirds employ intermediate routes in a migratory divide.

PubMed

Delmore, Kira E; Irwin, Darren E

2014-10-01

Migratory divides are contact zones between populations that use different routes to navigate around unsuitable areas on seasonal migration. Hybrids in divides have been predicted to employ intermediate and potentially inferior routes. We provide the first direct test of this hypothesis, using light-level geolocators to track birds breeding in a hybrid zone between Swainson's thrushes in western Canada. Compared to parental forms, hybrids exhibited increased variability in their migratory routes, with some using intermediate routes that crossed arid and mountainous regions, and some using the same routes as one parental group on fall migration and the other on spring migration. Hybrids also tended to use geographically intermediate wintering sites. Analysis of genetic variation across the hybrid zone suggests moderately strong selection against hybrids. These results indicate that seasonal migratory behaviour might be a source of selection against hybrids, supporting a possible role for migration in speciation. © 2014 John Wiley & Sons Ltd/CNRS.

Cellular level robotic surgery: Nanodissection of intermediate filaments in live keratinocytes.

PubMed

Yang, Ruiguo; Song, Bo; Sun, Zhiyong; Lai, King Wai Chiu; Fung, Carmen Kar Man; Patterson, Kevin C; Seiffert-Sinha, Kristina; Sinha, Animesh A; Xi, Ning

2015-01-01

We present the nanosurgery on the cytoskeleton of live cells using AFM based nanorobotics to achieve adhesiolysis and mimic the effect of pathophysiological modulation of intercellular adhesion. Nanosurgery successfully severs the intermediate filament bundles and disrupts cell-cell adhesion similar to the desmosomal protein disassembly in autoimmune disease, or the cationic modulation of desmosome formation. Our nanomechanical analysis revealed that adhesion loss results in a decrease in cellular stiffness in both cases of biochemical modulation of the desmosome junctions and mechanical disruption of intercellular adhesion, supporting the notion that intercellular adhesion through intermediate filaments anchors the cell structure as focal adhesion does and that intermediate filaments are integral components in cell mechanical integrity. The surgical process could potentially help reveal the mechanism of autoimmune pathology-induced cell-cell adhesion loss as well as its related pathways that lead to cell apoptosis. Copyright © 2015 Elsevier Inc. All rights reserved.

Using research to enhance student learning in intermediate mechanics

NASA Astrophysics Data System (ADS)

Ambrose, Bradley

2011-03-01

For many undergraduate physics majors the sophomore/junior level course in intermediate mechanics represents their first step beyond the introductory sequence. Over the past several years research has shown that intermediate mechanics students often encounter conceptual and reasoning difficulties similar to those that arise at the introductory level. Many difficulties suggest deeply-seated alternate conceptions, while others suggest loosely or spontaneously connected intuitions. Furthermore, students often do not connect the physics to the more sophisticated mathematics they are expected to use. This presentation will highlight results from research conducted at Grand Valley State University, the University of Maine (by co-PI Michael Wittmann) and pilot sites in the Intermediate Mechanics Tutorials project. These results, taken from the analysis of pretests (ungraded quizzes), written exams, and classroom observations, will illustrate specific student difficulties as well as examples of guided-inquiry teaching strategies that appear to address these difficulties. (Supported by NSF grants DUE-0441426 and DUE-0442388.)

Photopolymerization of Dienoyl Lipids Creates Planar Supported Poly(lipid) Membranes with Retained Fluidity.

PubMed

Orosz, Kristina S; Jones, Ian W; Keogh, John P; Smith, Christopher M; Griffin, Kaitlyn R; Xu, Juhua; Comi, Troy J; Hall, H K; Saavedra, S Scott

2016-02-16

Polymerization of substrate-supported bilayers composed of dienoylphosphatidylcholine (PC) lipids is known to greatly enhance their chemical and mechanical stability; however, the effects of polymerization on membrane fluidity have not been investigated. Here planar supported lipid bilayers (PSLBs) composed of dienoyl PCs on glass substrates were examined to assess the degree to which UV-initiated polymerization affects lateral lipid mobility. Fluorescence recovery after photobleaching (FRAP) was used to measure the diffusion coefficients (D) and mobile fractions of rhodamine-DOPE in unpolymerized and polymerized PSLBs composed of bis-sorbyl phosphatidylcholine (bis-SorbPC), mono-sorbyl-phosphatidylcholine (mono-SorbPC), bis-dienoyl-phosphatidylcholine (bis-DenPC), and mono-dienoyl phosphatidylcholine (mono-DenPC). Polymerization was performed in both the Lα and Lβ phase for each lipid. In all cases, polymerization reduced membrane fluidity; however, measurable lateral diffusion was retained which is attributed to a low degree of polymerization. The D values for sorbyl lipids were less than those of the denoyl lipids; this may be a consequence of the distal location of polymerizable group in the sorbyl lipids which may facilitate interleaflet bonding. The D values measured after polymerization were 0.1-0.8 of those measured before polymerization, a range that corresponds to fluidity intermediate between that of a Lα phase and a Lβ phase. This D range is comparable to ratios of D values reported for liquid-disordered (Ld) and liquid-ordered (Lo) lipid phases and indicates that the effect of UV polymerization on lateral diffusion in a dienoyl PSLB is similar to the transition from a Ld phase to a Lo phase. The partial retention of fluidity in UV-polymerized PSLBs, their enhanced stability, and the activity of incorporated transmembrane proteins and peptides is discussed.

Photopolymerization of dienoyl lipids creates planar supported poly(lipid) membranes with retained fluidity

PubMed Central

Orosz, Kristina S.; Jones, Ian W.; Keogh, John P.; Smith, Christopher M.; Griffin, Kaitlyn R.; Xu, Juhua; Comi, Troy J.; Hall, H. K.

2016-01-01

Polymerization of substrate-supported bilayers composed of dienoyl phosphatidylcholine (PC) lipids is known to greatly enhance their chemical and mechanical stability, however the effects of polymerization on membrane fluidity have not been investigated. Here planar supported lipid bilayers (PSLBs) composed of dienoyl PCs on glass substrates were examined to assess the degree to which UV-initiated polymerization affects lateral lipid mobility. Fluorescence recovery after photobleaching (FRAP) was used to measure the diffusion coefficients (D) and mobile fractions of rhodamine-DOPE in unpolymerized and polymerized PSLBs composed of bis-sorbyl phosphatidylcholine (bis-SorbPC), mono-sorbyl phosphatidylcholine (mono-SorbPC), bis-dienoyl phosphatidylcholine (bis-DenPC) and mono-dienoyl phosphatidylcholine (mono-DenPC). Polymerization was performed in both the Lα and Lβ phase for each lipid. In all cases, polymerization reduced membrane fluidity, however measurable lateral diffusion was retained which is attributed to a low degree of polymerization. The D values for sorbyl lipids were less than those of the denoyl lipids; this may be a consequence of the distal location of polymerizable group in the sorbyl lipids which may facilitate inter-leaflet bonding. The D values measured after polymerization were 0.1 to 0.8 of those measured before polymerization, a range that corresponds to fluidity intermediate between that of a Lα phase and a Lβ phase. This D range is comparable to ratios of D values reported for liquid-disordered (Ld) and liquid-ordered (Lo) lipid phases, and indicates that the effect of UV polymerization on lateral diffusion in a dienoyl PSLB is similar to the transition from a Ld phase to a Lo phase. The partial retention of fluidity in UV polymerized PSLBs, their enhanced stability, and the activity of incorporated transmembrane proteins and peptides is discussed. PMID:26794208

A finite element evaluation of mechanical function for 3 distal extension partial dental prosthesis designs with a 3-dimensional nonlinear method for modeling soft tissue.

PubMed

Nakamura, Yoshinori; Kanbara, Ryo; Ochiai, Kent T; Tanaka, Yoshinobu

2014-10-01

The mechanical evaluation of the function of partial removable dental prostheses with 3-dimensional finite element modeling requires the accurate assessment and incorporation of soft tissue behavior. The differential behaviors of the residual ridge mucosa and periodontal ligament tissues have been shown to exhibit nonlinear displacement. The mathematic incorporation of known values simulating nonlinear soft tissue behavior has not been investigated previously via 3-dimensional finite element modeling evaluation to demonstrate the effect of prosthesis design on the supporting tissues. The purpose of this comparative study was to evaluate the functional differences of 3 different partial removable dental prosthesis designs with 3-dimensional finite element analysis modeling and a simulated patient model incorporating known viscoelastic, nonlinear soft tissue properties. Three different designs of distal extension removable partial dental prostheses were analyzed. The stress distributions to the supporting abutments and soft tissue displacements of the designs tested were calculated and mechanically compared. Among the 3 dental designs evaluated, the RPI prosthesis demonstrated the lowest stress concentrations on the tissue supporting the tooth abutment and also provided wide mucosa-borne areas of support, thereby demonstrating a mechanical advantage and efficacy over the other designs evaluated. The data and results obtained from this study confirmed that the functional behavior of partial dental prostheses with supporting abutments and soft tissues are consistent with the conventional theories of design and clinical experience. The validity and usefulness of this testing method for future applications and testing protocols are shown. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Driving Forces of the Self-Assembly of Supramolecular Systems: Partially Ordered Mesophases

NASA Astrophysics Data System (ADS)

Shcherbina, M. A.; Chvalun, S. N.

2018-06-01

The main aspects are considered of the self-organization of a new class of liquid crystalline compounds, rigid sector-shaped and cone-shaped dendrons. Theoretical approaches to the self-assembly of different amphiphilic compounds (lipids, bolaamphiphiles, block copolymers, and polyelectrolytes) are described. Particular attention is given to the mesophase structures that emerge during the self-organization of mesophases characterized by intermediate degrees of ordering, e.g., plastic crystals, the rotation-crystalline phase in polymers, ordered and disordered two-dimensional columnar phases, and bicontinuous cubic phases of different symmetry.

Microgravity Processing of Oxide Superconductors

NASA Technical Reports Server (NTRS)

Hofmeister, William H.; Bayuzick, Robert J.; Vlasse, Marcus; McCallum, William; Peters, Palmer (Technical Monitor)

2000-01-01

The primary goal is to understand the microstructures which develop under the nonequilibrium solidification conditions achieved by melt processing in copper oxide superconductor systems. More specifically, to define the liquidus at the Y- 1:2:3 composition, the Nd-1:2:3 composition, and several intermediate partial substitution points between pure Y-1:2:3 and Nd-1:2:3. A secondary goal has been to understand resultant solidification morphologies and pathways under a variety of experimental conditions and to use this knowledge to better characterize solidification phenomena in these systems.

Passive cooling safety system for liquid metal cooled nuclear reactors

DOEpatents

Hunsbedt, Anstein; Boardman, Charles E.; Hui, Marvin M.; Berglund, Robert C.

1991-01-01

A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of partitions surrounding the reactor vessel in spaced apart relation forming intermediate areas for circulating heat transferring fluid which remove and carry away heat from the reactor vessel. The passive cooling system includes a closed primary fluid circuit through the partitions surrounding the reactor vessel and a partially adjoining secondary open fluid circuit for carrying transferred heat out into the atmosphere.

A simple kinetic model of a Ne-H2 Penning-plasma laser

NASA Astrophysics Data System (ADS)

Petrov, G. M.; Stefanova, M. S.; Pramatarov, P. M.

1995-09-01

A simple kinetic model of the Ne-H2 Penning-Plasma Laser (PPL) (NeI 585.3 nm) is proposed. The negative glow of a hollow cathode discharge at intermediate pressures is considered as the active medium. The balance equations for the upper and lower laser levels, electrons, ions and electron energy are solved. The dependences of the laser gain on the discharge conditions (Ne and H2 partial pressures, discharge current) are calculated and measured. The calculated values are in a good agreement with the experimental data.

Is the C-terminal flanking peptide of rat cholecystokinin double sulphated?

PubMed

Adrian, T E; Domin, J; Bacarese-Hamilton, A J; Bloom, S R

1986-02-03

A specific radioimmunoassay was developed to the predicted nine amino acid C-terminal flanking peptide of cholecystokinin (peptide serine serine, PSS). In aqueous extracts of rat brain, PSS was undetectable unless the extracts were first treated with arylsulphatase, which also resulted in desulphation of cholecystokinin. The reverse-phase HPLC analysis of partially desulphated extracts showed the presence of two peaks intermediate to the naturally occurring and the completely desulphated forms. It is therefore proposed that the CCK-flanking peptide PSS has both tyrosine residues sulphated.

Indirect passive cooling system for liquid metal cooled nuclear reactors

DOEpatents

Hunsbedt, Anstein; Boardman, Charles E.

1990-01-01

A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of partitions surrounding the reactor vessel in spaced apart relation forming intermediate areas for circulating heat transferring fluid which remove and carry away heat from the reactor vessel. The passive cooling system includes a closed primary fluid circuit through the partitions surrounding the reactor vessel and a partially adjoining secondary open fluid circuit for carrying transferred heat out into the atmosphere.

Distal extension mandibular removable partial denture with implant support

PubMed Central

Bural, Canan; Buzbas, Begum; Ozatik, Sebnem; Bayraktar, Gulsen; Emes, Yusuf

2016-01-01

This case report describes the fabrication of a distal extension removable partial denture (RPD) of a 65-year-old man with implant support. Loss of fibroelasticity of the peripheral tissues and reduced mandibular vestibular sulcular depth due to a previous surgical resection and radiotherapy at the right side were the main clinical factors that created difficulty for denture retention and stability. The fabrication of a mandibular RPD supported by anterior teeth and two bilaterally placed implants in the molar area to convert from Kennedy Class 1 design to Kennedy Class 3 implant-bounded RPD is reported. Retention and stability of the denture were improved with implant support on the distal extension site of the RPD. The common clinical problems about distally extended RPDs are lack of retention and stability due to the movement around the rotational axis. Dental implant placement to the distal edentulous site minimizes the potential dislodgement of the RPD is popular. Implant-supported RPD can be suggested as an advantageous and cost-effective treatment option for the partially edentulous patients. PMID:28042277

The Patient-Reported Information Multidimensional Exploration (PRIME) Framework for Investigating Emotions and Other Factors of Prostate Cancer Patients with Low Intermediate Risk Based on Online Cancer Support Group Discussions.

PubMed

Bandaragoda, Tharindu; Ranasinghe, Weranja; Adikari, Achini; de Silva, Daswin; Lawrentschuk, Nathan; Alahakoon, Damminda; Persad, Raj; Bolton, Damien

2018-06-01

This study aimed to use the Patient Reported Information Multidimensional Exploration (PRIME) framework, a novel ensemble of machine-learning and deep-learning algorithms, to extract, analyze, and correlate self-reported information from Online Cancer Support Groups (OCSG) by patients (and partners of patients) with low intermediate-risk prostate cancer (PCa) undergoing radical prostatectomy (RP), external beam radiotherapy (EBRT), and active surveillance (AS), and to investigate its efficacy in quality-of-life (QoL) and emotion measures. From patient-reported information on 10 OCSG, the PRIME framework automatically filtered and extracted conversations on low intermediate-risk PCa with active user participation. Side effects as well as emotional and QoL outcomes for 6084 patients were analyzed. Side-effect profiles differed between the methods analyzed, with men after RP having more urinary and sexual side effects and men after EBRT having more bowel symptoms. Key findings from the analysis of emotional expressions showed that PCa patients younger than 40 years expressed significantly high positive and negative emotions compared with other age groups, that partners of patients expressed more negative emotions than the patients, and that selected cohorts (< 40 years, > 70 years, partners of patients) have frequently used the same terms to express their emotions, which is indicative of QoL issues specific to those cohorts. Despite recent advances in patient-centerd care, patient emotions are largely overlooked, especially in younger men with a diagnosis of PCa and their partners. The authors present a novel approach, the PRIME framework, to extract, analyze, and correlate key patient factors. This framework improves understanding of QoL and identifies low intermediate-risk PCa patients who require additional support.

Experimental Data in Support of a Direct Displacement Mechanism for Type I/II l-Asparaginases*

PubMed Central

Schalk, Amanda M.; Antansijevic, Aleksandar; Caffrey, Michael; Lavie, Arnon

2016-01-01

Bacterial l-asparaginases play an important role in the treatment of certain types of blood cancers. We are exploring the guinea pig l-asparaginase (gpASNase1) as a potential replacement of the immunogenic bacterial enzymes. The exact mechanism used by l-asparaginases to catalyze the hydrolysis of asparagine into aspartic acid and ammonia has been recently put into question. Earlier experimental data suggested that the reaction proceeds via a covalent intermediate using a ping-pong mechanism, whereas recent computational work advocates the direct displacement of the amine by an activated water. To shed light on this controversy, we generated gpASNase1 mutants of conserved active site residues (T19A, T116A, T19A/T116A, K188M, and Y308F) suspected to play a role in hydrolysis. Using x-ray crystallography, we determined the crystal structures of the T19A, T116A, and K188M mutants soaked in asparagine. We also characterized their steady-state kinetic properties and analyzed the conversion of asparagine to aspartate using NMR. Our structures reveal bound asparagine in the active site that has unambiguously not formed a covalent intermediate. Kinetic and NMR assays detect significant residual activity for all of the mutants. Furthermore, no burst of ammonia production was observed that would indicate covalent intermediate formation and the presence of a ping-pong mechanism. Hence, despite using a variety of techniques, we were unable to obtain experimental evidence that would support the formation of a covalent intermediate. Consequently, our observations support a direct displacement rather than a ping-pong mechanism for l-asparaginases. PMID:26733195

Management of long span partially edentulous maxilla with fixed removable denture prosthesis

PubMed Central

Jeyavalan, Mahilan I.; Narasimman, M.; Venkatakrishnan, C. J.; Philip, Jacob M.

2012-01-01

Restoration of a long span partially edentulous maxilla with tooth supported prosthesis is challenging because of inherent anatomic limitations and unfavourable biomechanics present after the loss of teeth. A tooth supported fixed-removable prosthesis is a treatment option for restoration of such long span partially edentulous maxillary arches. This prosthesis meets the requirements for esthetics, phonetics, comfort, and hygiene, as well as favourable biomechanical stress distribution to the remaining natural tooth abutments. This article presents a procedure for fabrication of a fixed-removable prosthesis that has cement-retained custom cast bar metal substructure and a ball attachment retained removable superstructure prosthesis. PMID:23293488

Management of long span partially edentulous maxilla with fixed removable denture prosthesis.

PubMed

Jeyavalan, Mahilan I; Narasimman, M; Venkatakrishnan, C J; Philip, Jacob M

2012-07-01

Restoration of a long span partially edentulous maxilla with tooth supported prosthesis is challenging because of inherent anatomic limitations and unfavourable biomechanics present after the loss of teeth. A tooth supported fixed-removable prosthesis is a treatment option for restoration of such long span partially edentulous maxillary arches. This prosthesis meets the requirements for esthetics, phonetics, comfort, and hygiene, as well as favourable biomechanical stress distribution to the remaining natural tooth abutments. This article presents a procedure for fabrication of a fixed-removable prosthesis that has cement-retained custom cast bar metal substructure and a ball attachment retained removable superstructure prosthesis.

Hopper apparatuses for processing a bulk solid, and related systems and methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Westover, Tyler Lott; Ryan, John Chadron Benjamin; Matthews, Austin Colter

A hopper apparatus comprises a movable wall comprising opposing walls movably connected to a support assembly and oriented at acute angles relative to a central vertical axis of the support assembly, and movement control devices configured and positioned to move the opposing walls along the support assembly to control dimensions of a discharge outlet at least partially defined by converging ends of the opposing walls; a liner assembly comprising liner structures at least partially overlying inner surfaces of the opposing walls and configured to remain at least partially stationary relative to the opposing walls during movement of the opposing walls;more » and pressure sensors between the inner surfaces of opposing walls and portions of the liner structures thereover. A bulk solids processing system and a method of processing a bulk solid are also described.« less

Method of manufacturing a matrix for the detection of mismatches

DOEpatents

Ershov, Gennady Moiseevich; Mirzabekov, Andrei Darievich

1998-01-01

This method for preparing micromatrices consists in applying a specially-patterned intermediate layer of laser-absorbing substance on a solid support. The configuration of the sublayer fully corresponds to the topology of the manufactured matrix. The intermediate layer is further covered by a continuous layer of gel , the gel and the material of the support being transparent towards laser radiation. The gel layer is irradiated by a laser beam for a time needed to evaporate simultaneously the gel in the places immediately above the laser-absorbing sublayer and the sublayer itself. Oligonucleotides from a chosen set are then attached to the formed gel `cells`, one oligonucleotide to each cell. This method is intended for use in biotechnology, specifically for deciphering the nucleotide sequence of DNA.

Enhancement of C-H Oxidizing Ability in Co-O2  Complexes through an Isolated Heterobimetallic Oxo Intermediate.

PubMed

DeRosha, Daniel E; Mercado, Brandon Q; Lukat-Rodgers, Gudrun; Rodgers, Kenton R; Holland, Patrick L

2017-03-13

The characterization of intermediates formed through the reaction of transition-metal complexes with dioxygen (O 2 ) is important for understanding oxidation in biological and synthetic processes. Here, the reaction of the diketiminate-supported cobalt(I) complex L tBu Co with O 2 gives a rare example of a side-on dioxygen complex of cobalt. Structural, spectroscopic, and computational data are most consistent with its assignment as a cobalt(III)-peroxo complex. Treatment of L tBu Co(O 2 ) with low-valent Fe and Co diketiminate complexes affords isolable oxo species with M 2 O 2 "diamond" cores, including the first example of a crystallographically characterized heterobimetallic bis(μ-oxo) complex of two transition metals. The bimetallic species are capable of cleaving C-H bonds in the supporting ligands, and kinetic studies show that the Fe/Co heterobimetallic species activates C-H bonds much more rapidly than the Co/Co homobimetallic analogue. Thus heterobimetallic oxo intermediates provide a promising route for enhancing the rates of oxidation reactions. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cyclobutanone Mimics of Intermediates in Metallo-β-Lactamase Catalysis.

PubMed

Abboud, Martine I; Kosmopoulou, Magda; Krismanich, Anthony P; Johnson, Jarrod W; Hinchliffe, Philip; Brem, Jürgen; Claridge, Timothy D W; Spencer, James; Schofield, Christopher J; Dmitrienko, Gary I

2018-04-17

The most important resistance mechanism to β-lactam antibiotics involves hydrolysis by two β-lactamase categories: the nucleophilic serine and the metallo-β-lactamases (SBLs and MBLs, respectively). Cyclobutanones are hydrolytically stable β-lactam analogues with potential to inhibit both SBLs and MBLs. We describe solution and crystallographic studies on the interaction of a cyclobutanone penem analogue with the clinically important MBL SPM-1. NMR experiments using 19 F-labeled SPM-1 imply the cyclobutanone binds to SPM-1 with micromolar affinity. A crystal structure of the SPM-1:cyclobutanone complex reveals binding of the hydrated cyclobutanone through interactions with one of the zinc ions, stabilisation of the hydrate by hydrogen bonding to zinc-bound water, and hydrophobic contacts with aromatic residues. NMR analyses using a 13 C-labeled cyclobutanone support assignment of the bound species as the hydrated ketone. The results inform on how MBLs bind substrates and stabilize tetrahedral intermediates. They support further investigations on the use of transition-state and/or intermediate analogues as inhibitors of all β-lactamase classes. © 2018 Die Autoren. Veröffentlicht von Wiley-VCH Verlag GmbH & Co. KGaA.

Cyclobutanone Mimics of Intermediates in Metallo‐β‐Lactamase Catalysis

PubMed Central

Abboud, Martine I.; Kosmopoulou, Magda; Krismanich, Anthony P.; Johnson, Jarrod W.; Hinchliffe, Philip; Brem, Jürgen; Claridge, Timothy D. W.

2018-01-01

Abstract The most important resistance mechanism to β‐lactam antibiotics involves hydrolysis by two β‐lactamase categories: the nucleophilic serine and the metallo‐β‐lactamases (SBLs and MBLs, respectively). Cyclobutanones are hydrolytically stable β‐lactam analogues with potential to inhibit both SBLs and MBLs. We describe solution and crystallographic studies on the interaction of a cyclobutanone penem analogue with the clinically important MBL SPM‐1. NMR experiments using 19F‐labeled SPM‐1 imply the cyclobutanone binds to SPM‐1 with micromolar affinity. A crystal structure of the SPM‐1:cyclobutanone complex reveals binding of the hydrated cyclobutanone through interactions with one of the zinc ions, stabilisation of the hydrate by hydrogen bonding to zinc‐bound water, and hydrophobic contacts with aromatic residues. NMR analyses using a 13C‐labeled cyclobutanone support assignment of the bound species as the hydrated ketone. The results inform on how MBLs bind substrates and stabilize tetrahedral intermediates. They support further investigations on the use of transition‐state and/or intermediate analogues as inhibitors of all β‐lactamase classes. PMID:29250863

The development of expertise in pediatric rehabilitation therapists: changes in approach, self-knowledge, and use of enabling and customizing strategies.

PubMed

King, Gillian; Currie, Melissa; Bartlett, Doreen J; Gilpin, Michelle; Willoughby, Colleen; Tucker, Mary Ann; Strachan, Deborah; Baxter, Donna

2007-01-01

To examine the clinical decision making of novice, intermediate, and expert pediatric rehabilitation therapists from various disciplines. Two qualitative studies were conducted. Thirteen therapists took part in a study using the critical incident interview technique and 11 therapists took part in a study using the 'think aloud' technique. Therapists were classified as novice, intermediate, or expert in developmental level based on a cluster analysis of data collected using a multifaceted battery of assessment tools. Data were analyzed using a grounded theory approach. Expert and intermediate therapists differed from novices with respect to content, self-, and procedural knowledge. With increasing expertise, therapists use a supportive, educational, holistic, functional, and strengths-based approach; have heightened humility yet increased self-confidence; and understand how to facilitate and support client change and adaptation by using principles of engagement, coherence, and manageability. Expert therapists use enabling and customizing strategies to ensure a successful therapeutic session, optimize the child's functioning in the mid-term, and ensure child and family adaptation and accommodation over the longer-term.

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene.

PubMed

Call, Zachary; Suchewski, Meagan; Bradley, Christopher A

2017-03-20

A reliable, intermediate scale preparation of 1,2,3,4,5-pentamethylcyclopentadiene (Cp*H) is presented, based on modifications of existing protocols that derive from initial 2-bromo-2-butene lithiation followed by acid mediated dienol cyclization. The revised synthesis and purification of the ligand avoids the use of mechanical stirring while still permitting access to significant quantities (39 g) of Cp*H in good yield (58%). The procedure offers other additional benefits, including a more controlled quench of excess lithium during the production of the intermediate heptadienols and a simplified isolation of Cp*H of sufficient purity for metallation with transition metals. The ligand was subsequently used to synthesize [Cp*MCl2]2 complexes of both iridium and ruthenium to demonstrate the utility of the Cp*H prepared and purified by our method. The procedure outlined herein affords substantial quantities of a ubiquitous ancillary ligand support used in organometallic chemistry while minimizing the need for specialized laboratory equipment, thus providing a simpler and more accessible entry point into the chemistry of 1,2,3,4,5-pentamethylcyclopentadiene.

The HK-II Survey: Kinematics of Metal-Poor Stars in the Galaxy

NASA Astrophysics Data System (ADS)

Rhee, J.; Beers, T. C.

2003-12-01

The digitized HK-II survey (Rhee 2000, Ph.D. thesis, MSU) was originated as a follow-on to the HK-I survey of Beers and colleagues (e.g., Beers et al. 1992, AJ, 103, 1987). HK-I was based on visually-selected candidate metal-poor stars from objective-prism plates. Unfortunately, in the absence of color information, this selection technique introduced a rather severe temperature-related bias. As a result, the HK-I candidates do not include large numbers of metal-deficient giants. In HK-II, candidate metal-poor stars are quantitatively selected from digitized objective-prism spectra with JHK color information from the recently completeted 2MASS catalog. This approach eliminates much of the temperature bias. We have begun to survey candidate very metal-poor ([Fe/H] ≤ -2.0) giants from HK-II, over the magnitude range 11.0 ≤ B ≤ 16.0, covering some ˜7000 deg2 of intermediate to high Galactic-latitudes. Ongoing medium-resolution ( ˜ 1-2Å ) spectroscopic follow-up using NOAO observing facilities has allowed us to obtain, to date, some 1000 spectra (400, 450, and 150 spectra for red giants, subgiants near the main-sequence turnoff, and FHB/A stars, respectively) for the HK-II metal-poor star candidates. In particular, the detection rate of bona fide very metal-poor giants is about 45 %, which is quite encouraging. Most of the "mistakes" are slightly more metal-rich giants, with -2.0 < [Fe/H] < -1.0. Metallicities and radial velocities are determined from our spectroscopy, and proper motions for most of the program stars are obtained from the recently released UCAC2 astrometric survey catalog. Here we present an analysis of the full space motions for numerous metal-poor stars from the HK-II survey. A comparision of the chemical and kinematic properties between high- and low-halo populations (that is, giants vs. sub-giants) will aid us in understanding the formation history of the Milky Way. J.R. acknowledges partial support for this work by NASA through the AAS Small Research Grant Program. T.C.B. acknowledges partial support for this work from NSF grants AST 00-98508 and AST 00-98549.

Association between quality of response and outcomes in patients with newly diagnosed mantle cell lymphoma receiving VR-CAP versus R-CHOP in the phase 3 LYM-3002 study.

PubMed

Verhoef, Gregor; Robak, Tadeusz; Huang, Huiqiang; Pylypenko, Halyna; Siritanaratkul, Noppadol; Pereira, Juliana; Drach, Johannes; Mayer, Jiri; Okamoto, Rumiko; Pei, Lixia; Rooney, Brendan; Cakana, Andrew; van de Velde, Helgi; Cavalli, Franco

2017-05-01

In the phase 3 LYM-3002 study comparing intravenous VR-CAP with R-CHOP in patients with newly-diagnosed, measurable stage II-IV mantle cell lymphoma, not considered or ineligible for transplant, the median progression-free survival was significantly improved with VR-CAP (24.7 versus 14.4 months with R-CHOP; P <0.001). This post-hoc analysis evaluated the association between the improved outcomes and quality of responses achieved with VR-CAP versus R-CHOP in LYM-3002. Patients were randomized to six to eight 21-day cycles of VR-CAP or R-CHOP. Outcomes included progression-free survival, duration of response (both assessed by an independent review committee), and time to next anti-lymphoma treatment, evaluated by response (complete response/unconfirmed complete response and partial response), MIPI risk status, and maximum reduction of lymph-node measurements expressed as the sum of the product of the diameters. Within each response category, the median progression-free survival was longer for patients given VR-CAP than for those given R-CHOP (complete response/unconfirmed complete response: 40.9 versus 19.8 months; partial response: 17.1 versus 11.7 months, respectively); similarly, the median time to next anti-lymphoma treatment was longer among the patients given VR-CAP than among those treated with R-CHOP (complete response/unconfirmed complete response: not evaluable versus 26.6 months; partial response: 35.3 versus 24.3 months). Within the complete/unconfirmed complete and partial response categories, improvements in progression-free survival, duration of response and time to next anti-lymphoma treatment were more pronounced in patients with low-and intermediate-risk MIPI treated with VR-CAP than with R-CHOP. In each response category, more VR-CAP than R-CHOP patients had a sum of the product of the diameters nadir of 0 during serial radiological assessments. Results of this post-hoc analysis suggest a greater duration and quality of response in patients treated with VR-CAP in comparison with those treated with R-CHOP, with the improvements being more evident in patients with low- and intermediate-risk MIPI. LYM-3002 ClinicalTrials.gov: NCT00722137 . Copyright© Ferrata Storti Foundation.

Structures of aspartic acid-96 in the L and N intermediates of bacteriorhodopsin: analysis by Fourier transform infrared spectroscopy

NASA Technical Reports Server (NTRS)

Maeda, A.; Sasaki, J.; Shichida, Y.; Yoshizawa, T.; Chang, M.; Ni, B.; Needleman, R.; Lanyi, J. K.

1992-01-01

The light-induced difference Fourier transform infrared spectrum between the L or N intermediate minus light-adapted bacteriorhodopsin (BR) was measured in order to examine the protonated states and the changes in the interactions of carboxylic acids of Asp-96 and Asp-115 in these intermediates. Vibrational bands due to the protonated and unprotonated carboxylic acid were identified by isotope shift and band depletion upon substitution of Asp-96 or -115 by asparagine. While the signal due to the deprotonation of Asp-96 was clearly observed in the N intermediate, this residue remained protonated in L. Asp-115 was partially deprotonated in L. The C = O stretching vibration of protonated Asp-96 of L showed almost no shift upon 2H2O substitution, in contrast to the corresponding band of Asp-96 or Asp-115 of BR, which shifted by 9-12 cm-1 under the same conditions. In the model system of acetic acid in organic solvents, such an absence of the shift of the C = O stretching vibration of the protonated carboxylic acid upon 2H2O substitution was seen only when the O-H of acetic acid is hydrogen-bonded. The non-hydrogen-bonded monomer showed the 2H2O-dependent shift. Thus, the O-H bond of Asp-96 enters into hydrogen bonding upon conversion of BR to L. Its increased hydrogen bonding in L is consistent with the observed downshift of the O-H stretching vibration of the carboxylic acid of Asp-96.

Reappraisal of Hydatigera taeniaeformis (Batsch, 1786) (Cestoda: Taeniidae) sensu lato with description of Hydatigera kamiyai n. sp.

PubMed

Lavikainen, Antti; Iwaki, Takashi; Haukisalmi, Voitto; Konyaev, Sergey V; Casiraghi, Maurizio; Dokuchaev, Nikolai E; Galimberti, Andrea; Halajian, Ali; Henttonen, Heikki; Ichikawa-Seki, Madoka; Itagaki, Tadashi; Krivopalov, Anton V; Meri, Seppo; Morand, Serge; Näreaho, Anu; Olsson, Gert E; Ribas, Alexis; Terefe, Yitagele; Nakao, Minoru

2016-05-01

The common cat tapeworm Hydatigera taeniaeformis is a complex of three morphologically cryptic entities, which can be differentiated genetically. To clarify the biogeography and the host spectrum of the cryptic lineages, 150 specimens of H. taeniaeformis in various definitive and intermediate hosts from Eurasia, Africa and Australia were identified with DNA barcoding using partial mitochondrial cytochrome c oxidase subunit 1 gene sequences and compared with previously published data. Additional phylogenetic analyses of selected isolates were performed using nuclear DNA and mitochondrial genome sequences. Based on molecular data and morphological analysis, Hydatigera kamiyai n. sp. Iwaki is proposed for a cryptic lineage, which is predominantly northern Eurasian and uses mainly arvicoline rodents (voles) and mice of the genus Apodemus as intermediate hosts. Hydatigera taeniaeformis sensu stricto (s.s.) is restricted to murine rodents (rats and mice) as intermediate hosts. It probably originates from Asia but has spread worldwide. Despite remarkable genetic divergence between H. taeniaeformis s.s. and H. kamiyai, interspecific morphological differences are evident only in dimensions of rostellar hooks. The third cryptic lineage is closely related to H. kamiyai, but its taxonomic status remains unresolved due to limited morphological, molecular, biogeographical and ecological data. This Hydatigera sp. is confined to the Mediterranean and its intermediate hosts are unknown. Further studies are needed to classify Hydatigera sp. either as a distinct species or a variant of H. kamiyai. According to previously published limited data, all three entities occur in the Americas, probably due to human-mediated introductions. Copyright © 2016 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Topological Ordering and Viscosity in the Glassy Ge-Se System: The Search for a Structural or Dynamical Signature of the Intermediate Phase

NASA Astrophysics Data System (ADS)

Zeidler, Anita; Salmon, Philip S.; Whittaker, Dean A. J.; Pizzey, Keiron J.; Hannon, Alex C.

2017-11-01

The topological ordering of the network structure in vitreous Ge_xSe_{1-x} was investigated across most of the glass-forming region (0 ≤ x ≤ 0.4) by using high-resolution neutron diffraction to measure the Bhatia-Thornton number-number partial structure factor. This approach gives access to the composition dependence of the mean coordination number \\bar{n} and correlation lengths associated with the network ordering. The thermal properties of the samples were also measured by using temperature-modulated differential scanning calorimetry. The results do not point to a structural origin of the so-called intermediate phase, which in our work is indicated for the composition range 0.175(8) ≤ x ≤ 0.235(8) by a vanishingly-small non-reversing enthalpy near the glass transition. The midpoint of this range coincides with the mean-field expectation of a floppy-to-rigid transition at x = 0.20. The composition dependence of the liquid viscosity, as taken from the literature, was also investigated to look for a dynamical origin of the intermediate phase, using the Mauro-Yue-Ellison-Gupta-Allan (MYEGA) model to estimate the viscosity at the liquidus temperature. The evidence points to a maximum in the viscosity at the liquidus temperature, and a minimum in the fragility index, for the range 0.20 ≤ x ≤ 0.22. The utility of the intermediate phase as a predictor of the material properties in network glass-forming systems is discussed.

High Order Modulation Protograph Codes

NASA Technical Reports Server (NTRS)

Nguyen, Thuy V. (Inventor); Nosratinia, Aria (Inventor); Divsalar, Dariush (Inventor)

2014-01-01

Digital communication coding methods for designing protograph-based bit-interleaved code modulation that is general and applies to any modulation. The general coding framework can support not only multiple rates but also adaptive modulation. The method is a two stage lifting approach. In the first stage, an original protograph is lifted to a slightly larger intermediate protograph. The intermediate protograph is then lifted via a circulant matrix to the expected codeword length to form a protograph-based low-density parity-check code.

The Physical Demands of the Tree (Vriksasana) and One-Leg Balance (Utthita Hasta Padangusthasana) Poses Performed by Seniors: A Biomechanical Examination

PubMed Central

Yu, Sean S.-Y.; Wang, Man-Ying; Samarawickrame, Sachithra; Hashish, Rami; Kazadi, Leslie; Greendale, Gail A.; Salem, George J.

2012-01-01

Yoga is considered especially suitable for seniors because poses can be modified to accommodate practitioners' capabilities and limitations. In this study, biomechanical assessments on healthy seniors (n = 20; 70.1 ± 3.8 yr) were used to quantify the physical demands, (net joint moments of force [JMOFs] and muscular activation in the lower extremities) associated with the performance of 3 variations (introductory, intermediate, advanced) of 2 classical Hatha yoga poses – Tree and One-Leg Balance (OLB). ANOVA and Cohen's-d were used to contrast the postural variations statistically. The advanced (single-limb, without additional support) versions were hypothesized to generate the greatest demands, followed by the intermediate (single-limb [Tree] and bilateral-limb [OLB] with support) and introductory (bilateral-limb) versions. Our findings, however, suggest that common, long-held conceptions about pose modifications can be counter-intuitive. There was no difference between the intermediate and advanced Tree variations regarding hip and knee JMOFs in both the sagittal and frontal planes (P = 0.13–0.98). Similarly, OLB introductory and intermediate variations induced sagittal JMOFs that were in the opposite direction of the classic advanced pose version at the hip and knee (P < .001; d = 0.98–2.36). These biomechanical insights provide evidence that may be used by instructors, clinicians and therapists when selecting pose modifications for their yoga participants. PMID:22973410

Chitin biosynthesis: does it involve a lipid-bound intermediate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bade, M.L.

1983-01-01

In plants and animals, mechanical support is provided by insoluble extracellular fibers of high molecular weight which, in many invertebrates and fungi, consist in part of the nitrogen-containing carbohydrate chitin. At least in animals, chitin may be covalently bonded to protein. This possibility has given rise to the persistent search for a lipid-bound intermediate in chitin biosynthesis, since for certain glycoproteins such involvement is well established. Cell-free chitin synthetase systems from yeasts have been prepared, purified, and to some extent characterized. For such systems, in the cases where the product has been unequivocally identified as chitin, involvement of a lipid-boundmore » intermediate is most unlikely. Chitin synthesis by particulate cell-free preparations has been claimed for both crustaceans and insects. Careful inspection of the evidence in the latter instances reveals either that the synthetase is probably of microorganismic origin, or that the available results do not convincingly support the conclusions drawn from them. Semi-in vitro work involving short- or longer-term culture of epithelial cells synthesizing chitin has been done successfully in a number of laboratories. In cases where the question of lipid-bound intermediates has been addressed, the evidence has tended to militate against such involvement in insects and for it in crustaceans, but the evidence is as yet inconclusive. Further work is needed.« less

Provider and Patient Directed Financial Incentives to Improve Care and Outcomes for Patients with Diabetes

PubMed Central

Lorincz, Ilona S.; Lawson, Brittany C. T.

2012-01-01

Incentive programs directed at both providers and patients have become increasingly widespread. Pay-for-performance (P4P) where providers receive financial incentives to carry out specific care or improve clinical outcomes has been widely implemented. The existing literature indicates they probably spur initial gains which then level off or partially revert if incentives are withdrawn. The literature also indicates that process measures are easier to influence through P4P programs but that intermediate outcomes such as glucose, blood pressure, and cholesterol control are harder to influence, and the long term impact of P4P programs on health is largely unknown. Programs directed at patients show greater promise as a means to influence patient behavior and intermediate outcomes such as weight loss; however, the evidence for long term effects are lacking. In combination, both patient and provider incentives are potentially powerful tools but whether they are cost-effective has yet to be determined. PMID:23225214

Quench of paramagnetic orbital selective Mott phase and appearance of antiferromagnetic orbital selective slater phase in multiorbital correlated systems

NASA Astrophysics Data System (ADS)

Quan, Ya-Min; Liu, Da-Yong; Lin, Hai-Qing; Zou, Liang-Jian

2018-06-01

We present the modulation of magnetic order on the orbital selective Mott phases (OSMP) and the metal-insulator transitions (MIT) of multi-orbital Hubbard models by employing the rotationally invariant slave-boson methods. We show that at half filling, the well-known paramagnetic (PM) OSMP is completely covered by an antiferromagnetic (AFM) Slater insulator, and the PM Mott phase by an AFM Mott insulator when electron correlation strength varies from intermediate to strong both in two- and three-orbitals Hubbard systems. Away from half-filling, we find that a partial-polarized AFM orbital-selective Slater phase appears in the intermediate correlation regime, and an almost full-polarized AFM OSMP fully covers the paramagnetic OSMP. In addition, the ferromagnetic phase in the three-orbital case is more robust than that in the two-orbital case. These results demonstrate that the modulation of magnetic correlation to the quasiparticle spectra leads to much rich and more interesting MIT scenario in multiorbital correlated systems.

Solvent-driven reductive activation of carbon dioxide by gold anions.

PubMed

Knurr, Benjamin J; Weber, J Mathias

2012-11-14

Catalytic activation and electrochemical reduction of CO(2) for the formation of chemically usable feedstock and fuel are central goals for establishing a carbon neutral fuel cycle. The role of solvent molecules in catalytic processes is little understood, although solvent-solute interactions can strongly influence activated intermediate species. We use vibrational spectroscopy of mass-selected Au(CO(2))(n)(-) cluster ions to probe the solvation of AuCO(2)(-) as a model for a reactive intermediate in the reductive activation of a CO(2) ligand by a single-atom catalyst. For the first few solvent molecules, solvation of the complex preferentially occurs at the CO(2) moiety, enhancing reductive activation through polarization of the excess charge onto the partially reduced ligand. At higher levels of solvation, direct interaction of additional solvent molecules with the Au atom diminishes reduction. The results show how the solvation environment can enhance or diminish the effects of a catalyst, offering design criteria for single-atom catalyst engineering.

An infrared spectroscopy approach to follow β-sheet formation in peptide amyloid assemblies

NASA Astrophysics Data System (ADS)

Seo, Jongcheol; Hoffmann, Waldemar; Warnke, Stephan; Huang, Xing; Gewinner, Sandy; Schöllkopf, Wieland; Bowers, Michael T.; von Helden, Gert; Pagel, Kevin

2017-01-01

Amyloidogenic peptides and proteins play a crucial role in a variety of neurodegenerative disorders such as Alzheimer's and Parkinson's disease. These proteins undergo a spontaneous transition from a soluble, often partially folded form, into insoluble amyloid fibrils that are rich in β-sheets. Increasing evidence suggests that highly dynamic, polydisperse folding intermediates, which occur during fibril formation, are the toxic species in the amyloid-related diseases. Traditional condensed-phase methods are of limited use for characterizing these states because they typically only provide ensemble averages rather than information about individual oligomers. Here we report the first direct secondary-structure analysis of individual amyloid intermediates using a combination of ion mobility spectrometry-mass spectrometry and gas-phase infrared spectroscopy. Our data reveal that oligomers of the fibril-forming peptide segments VEALYL and YVEALL, which consist of 4-9 peptide strands, can contain a significant amount of β-sheet. In addition, our data show that the more-extended variants of each oligomer generally exhibit increased β-sheet content.

Wavelength assignment algorithm considering the state of neighborhood links for OBS networks

NASA Astrophysics Data System (ADS)

Tanaka, Yu; Hirota, Yusuke; Tode, Hideki; Murakami, Koso

2005-10-01

Recently, Optical WDM technology is introduced into backbone networks. On the other hand, as the future optical switching scheme, Optical Burst Switching (OBS) systems become a realistic solution. OBS systems do not consider buffering in intermediate nodes. Thus, it is an important issue to avoid overlapping wavelength reservation between partially interfered paths. To solve this problem, so far, the wavelength assignment scheme which has priority management tables has been proposed. This method achieves the reduction of burst blocking probability. However, this priority management table requires huge memory space. In this paper, we propose a wavelength assignment algorithm that reduces both the number of priority management tables and burst blocking probability. To reduce priority management tables, we allocate and manage them for each link. To reduce burst blocking probability, our method announces information about the change of their priorities to intermediate nodes. We evaluate its performance in terms of the burst blocking probability and the reduction rate of priority management tables.

Mechanism insight into the cyanide-catalyzed benzoin condensation: a density functional theory study.

PubMed

He, Yunqing; Xue, Ying

2010-09-02

The reaction mechanism of the cyanide-catalyzed benzoin condensation without protonic solvent assistance has been studied computationally for the first time employing the density functional theory (B3LYP) method in conjunction with 6-31+G(d,p) basis set. Four possible pathways have been investigated. A new proposed pathway on the basis of the Lapworth mechanism is determined to be the dominant pathway in aprotic solvent, in which the formation of the Lapworth's cyanohydrin intermediate is a sequence including three steps assisted by benzaldehyde, clearly manifesting that the reaction can take place in aprotic solvents such as DMSO. In this favorable pathway with six possible transition states located along the potential energy surface, the reaction of the cyanide/benzaldehyde complex with another benzaldehyde to afford an alpha-hydroxy ether is the rate-determining dynamically with the activation free energy barrier of 26.9 kcal/mol, and the step to form cyanohydrin intermediate from alpha-hydroxy ether is partially rate-determining for its relatively significant barrier 20.0 kcal/mol.

Ammonia formation by a thiolate-bridged diiron amide complex as a nitrogenase mimic

NASA Astrophysics Data System (ADS)

Li, Yang; Li, Ying; Wang, Baomin; Luo, Yi; Yang, Dawei; Tong, Peng; Zhao, Jinfeng; Luo, Lun; Zhou, Yuhan; Chen, Si; Cheng, Fang; Qu, Jingping

2013-04-01

Although nitrogenase enzymes routinely convert molecular nitrogen into ammonia under ambient temperature and pressure, this reaction is currently carried out industrially using the Haber-Bosch process, which requires extreme temperatures and pressures to activate dinitrogen. Biological fixation occurs through dinitrogen and reduced NxHy species at multi-iron centres of compounds bearing sulfur ligands, but it is difficult to elucidate the mechanistic details and to obtain stable model intermediate complexes for further investigation. Metal-based synthetic models have been applied to reveal partial details, although most models involve a mononuclear system. Here, we report a diiron complex bridged by a bidentate thiolate ligand that can accommodate HN=NH. Following reductions and protonations, HN=NH is converted to NH3 through pivotal intermediate complexes bridged by N2H3- and NH2- species. Notably, the final ammonia release was effected with water as the proton source. Density functional theory calculations were carried out, and a pathway of biological nitrogen fixation is proposed.

Tracking Co(I) Intermediate in operando in Photocatalytic Hydrogen Evolution by X-ray transient Absorption Spectroscopy and DFT Calculation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zhi-Jun; Zhan, Fei; Xiao, Hongyan

X-ray transient absorption spectroscopy (XTA) and optical transient spectroscopy (OTA) were used to probe the Co(I) intermediate generated in situ from an aqueous photocatalytic hydrogen evolution system, with [RuII(bpy)3]Cl2·6H2O as the photosensitizer, ascorbic acid/ascorbate as the electron donor, and the Co-polypyridyl complex ([CoII(DPABpy) Cl]Cl) as the pre-catalyst. Upon exposure to light, the XTA measured at Co K-edge visualizes the grow and decay of the Co(I) intermediate, and reveals its Co-N bond contraction of 0.09 ± 0.03 Å. Density functional theory (DFT) calculations support the bond contraction and illustrate that the metal-to-ligand π back-bonding greatly stabilizes the penta-coordinated Co(I) intermediate, whichmore » provides easy photon access. To the best of our knowledge, this is the first example of capturing the penta-coordinated Co(I) intermediate in operando with bond contraction by XTA, thereby providing new insights for fundamental understanding of structure– function relationship of cobalt-based molecular catalysts.« less

[Fixed partial denture on implants. Prosthodontic and biomechanical considerations].

PubMed

del Rio Highsmith, J; Garcia-Lomas, S; Mandinazagoitia, C

1990-01-01

In this issue are analyzed the factors that support the selection of the partial edentulous patients, for the construction of partial fixed prosthesis implantosupported, and the biomechanical considerations that we have to consider in relation to: relation implant-bone, the use of natural teeth, part of the jaw, length of the space, opponent jaw and materials.

Correlations between age, kinematics, and chemistry as seen by the RAVE survey

NASA Astrophysics Data System (ADS)

Wojno, Jennifer; Kordopatis, Georges; Steinmetz, Matthias; McMillan, Paul; Binney, James; Famaey, Benoit; Monari, Giacomo; Minchev, Ivan; Wyse, Rosemary F. G.; Antoja, Teresa; Siebert, Arnaud; Carrillo, Ismael; Bland-Hawthorn, Joss; Grebel, Eva K.; Zwitter, Tomaž; Bienaymé, Olivier; Gibson, Brad; Kunder, Andrea; Munari, Ulisse; Navarro, Julio; Parker, Quentin; Reid, Warren; Seabroke, George

2018-07-01

We explore the connections between stellar age, chemistry, and kinematics across a Galactocentric distance of 7.5 < R(kpc) < 9.0, using a sample of ˜12 000 intermediate-mass (FGK) turn-off stars observed with the RAdial Velocity Experiment (RAVE) survey. The kinematics of this sample are determined using radial velocity measurements from RAVE, and parallax and proper motion measurements from the Tycho-Gaia Astrometric Solution (TGAS). In addition, ages for RAVE stars are determined using a Bayesian method, taking TGAS parallaxes as a prior. We divide our sample into young (0 < τ < 3 Gyr) and old (8 < τ < 13 Gyr) populations, and then consider different metallicity bins for each of these age groups. We find significant differences in kinematic trends of young and old, metal-poor and metal-rich, stellar populations. In particular, we find a strong metallicity dependence in the mean Galactocentric radial velocity as a function of radius (partial {V_R}/partial R) for young stars, with metal-rich stars having a much steeper gradient than metal-poor stars. For partial {V_{φ }}/partial R, young, metal-rich stars significantly lag the LSR with a slightly positive gradient, while metal-poor stars show a negative gradient above the LSR. We interpret these findings as correlations between metallicity and the relative contributions of the non-axisymmetries in the Galactic gravitational potential (the spiral arms and the bar) to perturb stellar orbits.

Conformational state interactions provide clues to the pharmacochaperone potential of serotonin transporter partial substrates

PubMed Central

Bhat, Shreyas; Hasenhuetl, Peter S.; Kasture, Ameya; El-Kasaby, Ali; Baumann, Michael H.; Blough, Bruce E.; Sucic, Sonja; Sandtner, Walter; Freissmuth, Michael

2017-01-01

Point mutations in SLC6 transporters cause misfolding, which can be remedied by pharmacochaperones. The serotonin transporter (SERT/SLC6A4) has a rich pharmacology including inhibitors, releasers (amphetamines, which promote the exchange mode), and more recently, discovered partial substrates. We hypothesized that partial substrates trapped the transporter in one or several states of the transport cycle. This conformational trapping may also be conducive to folding. We selected naphthylpropane-2-amines of the phenethylamine library (PAL) including the partial substrate PAL1045 and its congeners PAL287 and PAL1046. We analyzed their impact on the transport cycle of SERT by biochemical approaches and by electrophysiological recordings; substrate-induced peak currents and steady-state currents monitored the translocation of substrate and co-substrate Na+ across the lipid bilayer and the transport cycle, respectively. These experiments showed that PAL1045 and its congeners bound with different affinities (ranging from nm to μm) to various conformational intermediates of SERT during the transport cycle. Consistent with the working hypothesis, PAL1045 was the most efficacious compound in restoring surface expression and transport activity to the folding-deficient mutant SERT-601PG602-AA. These experiments provide a proof-of-principle for a rational search for pharmacochaperones, which may be useful to restore function to clinically relevant folding-deficient transporter mutants. PMID:28842491

Peroxisome Degradation by Microautophagy in Pichia pastoris: Identification of Specific Steps and Morphological Intermediates

PubMed Central

Sakai, Yasuyoshi; Koller, Antonius; Rangell, Linda K.; Keller, Gilbert A.; Subramani, Suresh

1998-01-01

We used the dye N-(3-triethylammoniumpropyl)-4-(p-diethylaminophenylhexatrienyl) pyridinium dibromide (FM4-64) and a fusion protein, consisting of the green fluorescent protein appended to the peroxisomal targeting signal, Ser-Lys-Leu (SKL), to label the vacuolar membrane and the peroxisomal matrix, respectively, in living Pichia pastoris cells and followed by fluorescence microscopy the morphological and kinetic intermediates in the vacuolar degradation of peroxisomes by microautophagy and macroautophagy. Structures corresponding to the intermediates were also identified by electron microscopy. The kinetics of appearance and disappearance of these intermediates is consistent with a precursor–product relationship between intermediates, which form the basis of a model for microautophagy. Inhibitors affecting different steps of microautophagy did not impair peroxisome delivery to the vacuole via macroautophagy, although inhibition of vacuolar proteases affected the final vacuolar degradation of green fluorescent protein (S65T mutant version [GFP])-SKL via both autophagic pathways. P. pastoris mutants defective in peroxisome microautophagy (pag mutants) were isolated and characterized for the presence or absence of the intermediates. These mutants, comprising 6 complementation groups, support the model for microautophagy. Our studies indicate that the microautophagic degradation of peroxisomes proceeds via specific intermediates, whose generation and/or processing is controlled by PAG gene products, and shed light on the poorly understood phenomenon of peroxisome homeostasis. PMID:9566964

Crystal structure and magnetic properties of '{alpha} Prime Prime -Fe{sub 16}N{sub 2}' containing residual {alpha}-Fe prepared by low-temperature ammonia nitridation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamashita, S.; Masubuchi, Y.; Nakazawa, Y.

2012-10-15

Slight enhancement of saturation magnetization to 219 A m{sup 2} kg{sup -1} was observed from 199 A m{sup 2} kg{sup -1} for the original {alpha}-Fe on the intermediate nitrided mixture of '{alpha} Prime Prime -Fe{sub 16}N{sub 2}' with residual {alpha}-Fe among the low temperature ammonia nitridation products under 5 T magnetic field at room temperature. The value changed not linearly against the yield as had been expected. Crystal structure refinement indicated that the phase similar to {alpha} Prime Prime -Fe{sub 16}N{sub 2} had deviations on its lattice constants and positional parameters, compared to previously reported values for {alpha} Prime Primemore » -Fe{sub 16}N{sub 2}. Spin-polarized total energy calculations were performed using the projector-augmented wave method as implemented in the Vienna ab-initio simulation package (VASP) to calculate magnetic moment on the refined crystal structure of the intermediate '{alpha} Prime Prime -Fe{sub 16}N{sub 2}'. The calculations supported the observed magnetization enhancement in the intermediate nitridation product. - Graphical abstract: Crystal structural parameters slightly change in the intermediate nitrided '{alpha} Prime Prime -Fe{sub 16}N{sub 2}' from those in {alpha} Prime Prime -Fe{sub 16}N{sub 2} to show the magnetization maxima in the mixture of '{alpha} Prime Prime -Fe{sub 16}N{sub 2}' and the residual {alpha}-F. Highlights: Black-Right-Pointing-Pointer Larger magnetization was observed than the value of Fe{sub 16}N{sub 2} on its intermediate nitrided mixture with residual {alpha}-Fe. Black-Right-Pointing-Pointer The enhancement was related to the crystal structural deviation from Fe{sub 16}N{sub 2} on the intermediate nitride. Black-Right-Pointing-Pointer It was supported by spin-polarized total energy calculation using the deviated structure.« less

Adsorption Behavior, Thermodynamics, and Kinetics of the Methanol Decomposition Reaction on defective graphene-supported Pt13

NASA Astrophysics Data System (ADS)

Gasper, Raymond; Ramasubramaniam, Ashwin

Defective graphene has been shown experimentally to be an excellent support for transition-metal electrocatalysts in direct methanol fuel cells. Prior computational modeling has shown that the improved catalytic activity of graphene-supported metal clusters is in part due to increased resistance to catalyst sintering and CO poisoning, but the increased reaction rate for the methanol decomposition reaction (MDR) is not yet fully explained. Using DFT, we investigate the adsorption of MDR intermediates and reaction thermodynamics on defective graphene-supported Pt13 nanoclusters with realistic, low-symmetry morphologies. We find that the support-induced shifts in Pt13 electronic structure correlate well with a rigid shift in adsorption of MDR intermediates, and that adsorption energy scaling relationships perform well on the low-symmetry surface. We investigate the reaction kinetics and thermodynamics, including testing the effectiveness of scaling relationships for predicting reaction barriers on the nanoclusters. Using these fundamental data, we perform microkinetic modeling to quantify the effect of the support on the MDR, and to understand how the support influences surface coverages, CO poisoning, and the relationships between reaction pathways. Funded by U.S. Department of Energy under Award Number DE-SC0010610. Computational resources were provided by National Energy Research Scientific Computing Center.

Three-dimensional finite element analysis of implant-assisted removable partial dentures.

PubMed

Eom, Ju-Won; Lim, Young-Jun; Kim, Myung-Joo; Kwon, Ho-Beom

2017-06-01

Whether the implant abutment in implant-assisted removable partial dentures (IARPDs) functions as a natural removable partial denture (RPD) tooth abutment is unknown. The purpose of this 3-dimensional finite element study was to analyze the biomechanical behavior of implant crown, bone, RPD, and IARPD. Finite element models of the partial maxilla, teeth, and prostheses were generated on the basis of a patient's computed tomographic data. The teeth, surveyed crowns, and RPDs were created in the model. With the generated components, four 3-dimensional finite element models of the partial maxilla were constructed: tooth-supported RPD (TB), implant-supported RPD (IB), tooth-tissue-supported RPD (TT), and implant-tissue-supported RPD (IT) models. Oblique loading of 300 N was applied on the crowns and denture teeth. The von Mises stress and displacement of the denture abutment tooth and implant system were identified. The highest von Mises stress values of both IARPDs occurred on the implants, while those of both natural tooth RPDs occurred on the frameworks of the RPDs. The highest von Mises stress of model IT was about twice that of model IB, while the value of model TT was similar to that of model TB. The maximum displacement was greater in models TB and TT than in models IB and IT. Among the 4 models, the highest maximum displacement value was observed in the model TT and the lowest value was in the model IB. Finite element analysis revealed that the stress distribution pattern of the IARPDs was different from that of the natural tooth RPDs and the stress distribution of implant-supported RPD was different from that of implant-tissue-supported RPD. When implants are used for RPD abutments, more consideration concerning the RPD design and the number or location of the implant is necessary. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

EAO consensus conference: economic evaluation of implant-supported prostheses.

PubMed

Beikler, Thomas; Flemmig, Thomas F

2015-09-01

There are various alternatives for the management of oral conditions that may lead to or already have lead to partial or full edentulism. Economic evaluations measure the efficiency of alternative healthcare interventions and provide useful information for decision-making and the allocation of scarce resources. The current English literature dealing with "cost-effectiveness" of dental implant therapy versus different alternative treatment modalities, that is, complete and fixed partial dentures, root canal, and periodontal treatment, has been included in this narrative review. Due to the high heterogeneity within the literature, a meta-analysis could not be conducted. The available evidence from economic evaluations indicated that for the treatment of central incisors with irreversible pulpitis and coronal lesions, root canal treatments were most cost-effective initial treatment options. When initial root canal treatments failed, orthograde retreatments were most cost-effective. When root canal retreatments failed, extractions and replacement with single implant-supported crowns were more cost-effective compared to fixed or removable partial dentures. In the treatment of periodontitis in molars with Class I furcation invasion, non-surgical periodontal therapy was more effective and costed less than implant-supported single crowns. For the replacement of single missing teeth, two evaluations indicated that implant-supported single crowns provided better outcomes in terms of greater quality-adjusted tooth years or survival rates at lower costs compared to fixed partial prostheses. Another economic evaluation found that implant-supported crowns costed more, but provided greater survival rates compared to fixed partial dentures. For the restoration of edentulous mandibles, two evaluations indicated that overdentures retained by two or four implants improved oral health-related quality of life outcomes, but costed more than complete dentures. To better assess the efficiency of implant-supported prostheses in various clinical conditions, more economic evaluations are needed that follow well-established methodologies in health economics. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Presence of Peierls pairing and absence of insulator-to-metal transition in VO2 (A): a structure-property relationship study.

PubMed

Popuri, S R; Artemenko, A; Decourt, R; Villesuzanne, A; Pollet, M

2017-03-01

Layered vanadium oxides have been extensively explored due to their interesting metal-insulator transitions and energy conversion/storage applications. In the present study, we have successfully synthesized VO 2 (A) polymorph powder samples by a single-step hydrothermal synthesis process and consolidated them using spark plasma sintering. The structural and electronic properties of VO 2 (A) are measured over a large temperature range from liquid helium, across the structural transition (400-440 K) and up to 500 K. The structural analysis around this transition reveals an antiferrodistorsive to partially ferrodistorsive ordering upon cooling. It is followed by a progressive antiferromagnetic spin pairing which fully settles at about 150 K. The transport measurements show that, in contrast to the rutile archetype VO 2 (R/M1), the structural transition comes with a transition from semiconductor to band-type insulator. Under these circumstances, we propose a scenario with a high temperature antiferrodistorsive paramagnetic semiconducting phase, followed by an intermediate regime with a partially ferrodistorsive paramagnetic semiconducting phase, and finally a low temperature partially ferrodistorsive antiferromagnetic band insulator phase with a possible V-V Peierls-type pairing.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Papajak, Ewa; Truhlar, Donald G.

We present sets of convergent, partially augmented basis set levels corresponding to subsets of the augmented “aug-cc-pV(n+d)Z” basis sets of Dunning and co-workers. We show that for many molecular properties a basis set fully augmented with diffuse functions is computationally expensive and almost always unnecessary. On the other hand, unaugmented cc-pV(n+d)Z basis sets are insufficient for many properties that require diffuse functions. Therefore, we propose using intermediate basis sets. We developed an efficient strategy for partial augmentation, and in this article, we test it and validate it. Sequentially deleting diffuse basis functions from the “aug” basis sets yields the “jul”,more » “jun”, “may”, “apr”, etc. basis sets. Tests of these basis sets for Møller-Plesset second-order perturbation theory (MP2) show the advantages of using these partially augmented basis sets and allow us to recommend which basis sets offer the best accuracy for a given number of basis functions for calculations on large systems. Similar truncations in the diffuse space can be performed for the aug-cc-pVxZ, aug-cc-pCVxZ, etc. basis sets.« less

Intermediate-consumer identity and resources alter a food web with omnivory.

PubMed

Kneitel, Jamie M

2007-07-01

1. Omnivory is an important interaction that has been the centre of numerous theoretical and empirical studies in recent years. Most of these studies examine the conditions necessary for coexistence between an omnivore and an intermediate consumer. Trait variation in ecological interactions (competition and predator tolerance) among intermediate consumers has not been considered in previous empirical studies despite the evidence that variation in species-specific traits can have important community-level effects. 2. I conducted a multifactorial microcosm experiment using species from the Sarracenia purpurea phytotelmata community, organisms that inhabit the water collected within its modified leaves. The basal trophic level consisted of bacterial decomposers, the second trophic level (intermediate consumers) consisted of protozoa and rotifers, and the third trophic level (omnivore) were larvae of the pitcher plant mosquito Wyeomyia smithii. Trophic level number (1, 2 and 3), resources (low and high), omnivore density (low and high) and intermediate consumer (monoculture of five protozoa and rotifers) identity were manipulated. Abundance of the basal trophic level, intermediate consumers, and growth of the omnivore were measured, as well as time to extinction (intermediate consumers) and time to pupation (mosquito larvae). 3. The presence of different intermediate consumers affected both bacteria abundance and omnivore growth. At high resource levels, Poteriochromonas, Colpidium and Habrotrocha rosa reduced bacteria densities greater than omnivore reduction of bacteria. Mosquito larvae did not pupate at low resource levels except when Poteriochromonas and Colopoda were present as intermediate consumers. Communities with H. rosa were the only ones consistent with the prediction that omnivores should exclude intermediate consumers at high resources. 4. These results had mixed support for predictions from omnivory food web theory. Intermediate consumers responded and affected this community differently under different community structures and resource levels. Consequently, variation in species-specific traits can have important population- and community-level effects and needs to be considered in food webs with omnivory.

Pressures of Partial Crystallization of Magmas Along Transforms: Implications for Crustal Accretion

NASA Astrophysics Data System (ADS)

Scott, J. L.; Zerda, C.; Brown, D.; Ciaramitaro, S. C.; Barton, M.

2016-12-01

Plate spreading at mid-ocean ridges is responsible for the creation of most of the crust on earth. The ridge system is very complex and many questions remain unresolved. Among these is the nature of magma plumbing systems beneath transform faults. Pervious workers have suggested that increased conductive cooling along transforms promotes higher pressures of partial crystallization, and that this explains the higher partial pressures of crystallization inferred for magmas erupted along slow spreading ridges compared to magmas erupted along faster spreading ridges. To test this hypothesis, we undertook a detailed analysis of pressures of partial crystallization for magmas erupted at 3 transforms along the fast to intermediate spreading East Pacific Rise(Blanco, Clipperton, and Siqueiros) and 3 transforms along the slow spreading Mid Atlantic Ridge(Famous Transform B, Kane, and 15°20'N). Pressures of partial crystallization were calculated from the compositions of glasses (quenched liquids) lying along the P (and T) dependent olivine, plagioclase, and augite cotectic using the method described by Kelley and Barton (2008). Published analyses of mid-ocean ridge basalt glasses sampled from these transforms and surrounding ridge segments were used as input data. Samples with anomalous chemical compositions and samples that yielded pressures associated with unrealistically large uncertainties were filtered out of the database. The pressures of partial crystallization for the remaining 916 samples ranged from 0 to 520 MPa with the great majority ( 95%) of sample returning pressures of less than 300 MPa. Pressures of < 300 MPa are within error of the pressure range associated with partial crystallization within oceanic crust with a thickness of 7 km. Higher (sub-crustal) pressures (>300 MPa) are associated with a small number of samples from the Pacific segments. Except for the Blanco, pressures of partial crystallization do not increase as transforms are approached. These observations contrast with those of previous workers, who reported anomalously high pressures (up to 1000 MPa) for a large number of samples erupted near both Atlantic and Pacific Transforms. We conclude that higher rates of cooling along transform does not have a major effect on the onset of partial crystallization along the mid-ocean ridges

Factors associated with blood oxygen partial pressure and carbon dioxide partial pressure regulation during respiratory extracorporeal membrane oxygenation support: data from a swine model

PubMed Central

Park, Marcelo; Mendes, Pedro Vitale; Costa, Eduardo Leite Vieira; Barbosa, Edzangela Vasconcelos Santos; Hirota, Adriana Sayuri; Azevedo, Luciano Cesar Pontes

2016-01-01

Objective The aim of this study was to explore the factors associated with blood oxygen partial pressure and carbon dioxide partial pressure. Methods The factors associated with oxygen - and carbon dioxide regulation were investigated in an apneic pig model under veno-venous extracorporeal membrane oxygenation support. A predefined sequence of blood and sweep flows was tested. Results Oxygenation was mainly associated with extracorporeal membrane oxygenation blood flow (beta coefficient = 0.036mmHg/mL/min), cardiac output (beta coefficient = -11.970mmHg/L/min) and pulmonary shunting (beta coefficient = -0.232mmHg/%). Furthermore, the initial oxygen partial pressure and carbon dioxide partial pressure measurements were also associated with oxygenation, with beta coefficients of 0.160 and 0.442mmHg/mmHg, respectively. Carbon dioxide partial pressure was associated with cardiac output (beta coefficient = 3.578mmHg/L/min), sweep gas flow (beta coefficient = -2.635mmHg/L/min), temperature (beta coefficient = 4.514mmHg/ºC), initial pH (beta coefficient = -66.065mmHg/0.01 unit) and hemoglobin (beta coefficient = 6.635mmHg/g/dL). Conclusion In conclusion, elevations in blood and sweep gas flows in an apneic veno-venous extracorporeal membrane oxygenation model resulted in an increase in oxygen partial pressure and a reduction in carbon dioxide partial pressure 2, respectively. Furthermore, without the possibility of causal inference, oxygen partial pressure was negatively associated with pulmonary shunting and cardiac output, and carbon dioxide partial pressure was positively associated with cardiac output, core temperature and initial hemoglobin. PMID:27096671

Evidence for a New Intermediate Phase in a Strongly Correlated 2D System near Wigner Crystallization

NASA Astrophysics Data System (ADS)

Gao, Xuan; Qiu, Richard; Goble, Nicholas; Serafin, Alex; Yin, Liang; Xia, Jian-Sheng; Sullivan, Neil; Pfeiffer, Loren; West, Ken

How the two dimensional (2D) quantum Wigner crystal (WC) transforms into the metallic liquid phase remains an outstanding problem in physics. In theories considering the 2D WC to liquid transition in the clean limit, it was suggested that a number of intermediate phases might exist. We have studied the transformation between the metallic fluid phase and the low magnetic field reentrant insulating phase (RIP) which was interpreted as due to the WC [Qiu et al., PRL 108, 106404 (2012)], in a strongly correlated 2D hole system in GaAs quantum well with large interaction parameter rs (~20-30) and high mobility. Instead of a sharp transition, we found that increasing density (or lowering rs) drives the RIP into a state where the incipient RIP coexists with Fermi liquid. This apparent mixture phase intermediate between Fermi liquid and WC also exhibits a non-trivial temperature dependent resistivity behavior which can be qualitatively understood by the reversed melting of WC in the mixture, in analogy to the Pomeranchuk effect in the solid-liquid mixture of Helium-3. X.G. thanks NSF (DMR-0906415) for supporting work at CWRU. Experiments at the NHMFL High B/T Facility were supported by NSF Grant 0654118 and the State of Florida. L.P. thanks the Gordon and Betty Moore Foundation and NSF MRSEC (DMR-0819860) for support.

Intermediate-Band Photometric Luminosity Descrimination for M Stars

NASA Astrophysics Data System (ADS)

Robertson, T. H.; Furiak, N. M.

1995-12-01

Synthetic photometry has been used to design an intermediate-band filter to be used with CCD cameras to facilitate the luminosity classification of M stars. Spectrophotometric data published by Gunn & Stryker (1983) were used to test various bandwidths and centers. Based on these calculations an intermediate-band filter has been purchased. This filter is being used in conjunction with standard BVRI filters to test its effectiveness in luminosity classification of M stars having a wide range of temperatures and different chemical compositions. The results of the theoretical calculations, filter design specifications and preliminary results of the testing program are presented. This research is supported in part by funds provided by Ball State University, The Fund for Astrophysical Research and the Indiana Academy of Science.

Isotope Effects Reveal the Mechanism of Enamine Formation in l-Proline-Catalyzed α-Amination of Aldehydes.

PubMed

Ashley, Melissa A; Hirschi, Jennifer S; Izzo, Joseph A; Vetticatt, Mathew J

2016-02-17

The mechanism of l-proline-catalyzed α-amination of 3-phenylpropionaldehyde was studied using a combination of experimental kinetic isotope effects (KIEs) and theoretical calculations. Observation of a significant carbonyl (13)C KIE and a large primary α-deuterium KIE support rate-determining enamine formation. Theoretical predictions of KIEs exclude the widely accepted mechanism of enamine formation via intramolecular deprotonation of an iminium carboxylate intermediate. An E2 elimination mechanism catalyzed by a bifunctional base that directly forms an N-protonated enamine species from an oxazolidinone intermediate accounts for the experimental KIEs. These findings provide the first experimental picture of the transition-state geometry of enamine formation and clarify the role of oxazolidinones as nonparasitic intermediates in proline catalysis.

The Impact of Surgeon Volume on Perioperative Outcomes and Cost for Patients Receiving Robotic Partial Nephrectomy.

PubMed

Khandwala, Yash S; Jeong, In Gab; Kim, Jae Heon; Han, Deok Hyun; Li, Shufeng; Wang, Ye; Chang, Steven L; Chung, Benjamin I

2017-09-01

Little is known about the impact of surgeon volume on the success of the robot-assisted partial nephrectomy (RAPN). The objective of this study was to compare the perioperative outcomes and cost related to RAPN by annual surgeon volumes. Using the Premier Hospital Database, we retrospectively analyzed 39,773 patients who underwent RAPN between 2003 and 2015 in the United States. Surgeons for each index case were grouped into quintiles for each respective year. Outcomes were 90-day postoperative complications, operating room time (ORT), blood transfusion, length of stay, and direct hospital costs. Logistic regression and generalized linear models were used to identify factors predicting complications and cost. After accounting for patient and hospital demographics, high- and very high-volume surgeons had 40% and 42% decreased odds of having major complications (p = 0.045 and p = 0.027, respectively). Surgeons with higher volumes were associated with fewer odds of prolonged ORT (0.68 for low, 0.72 for intermediate, 0.56 for high, 0.44 for very high volume, all p < 0.05) and length of hospital stay (0.67 for intermediate, 0.51 for high, 0.45 for very high volume, all p < 0.01) compared with very low-volume surgeons. The 90-day hospital cost was also significantly lower for the surgeons with higher volume, but the statistical significance diminished after consideration of hospital clustering. Surgeons with very high RAPN volumes were found to have superior perioperative outcomes. Although cost of care appeared to correlate with surgeon volume, there may be other more influential factors predicting cost.

On the interrelation of multiplication and division in secondary school children

PubMed Central

Huber, Stefan; Fischer, Ursula; Moeller, Korbinian; Nuerk, Hans-Christoph

2013-01-01

Multiplication and division are conceptually inversely related: Each division problem can be transformed into as a multiplication problem and vice versa. Recent research has indicated strong developmental parallels between multiplication and division in primary school children. In this study, we were interested in (i) whether these developmental parallels persist into secondary school, (ii) whether similar developmental parallels can be observed for simple and complex problems, (iii) whether skill level modulates this relationship, and (iv) whether the correlations are specific and not driven by general cognitive or arithmetic abilities. Therefore, we assessed performance of 5th and 6th graders attending two secondary school types of the German educational system in simple and complex multiplication as well as division while controlling for non-verbal intelligence, short-term memory, and other arithmetic abilities. Accordingly, we collected data from students differing in skills levels due to either age (5th < 6th grade) or school type (general < intermediate secondary school). We observed moderate to strong bivariate and partial correlations between multiplication and division with correlations being higher for simple tasks but nevertheless reliable for complex tasks. Moreover, the association between simple multiplication and division depended on students' skill levels as reflected by school types, but not by age. Partial correlations were higher for intermediate than for general secondary school children. In sum, these findings emphasize the importance of the inverse relationship between multiplication and division which persists into later developmental stages. However, evidence for skill-related differences in the relationship between multiplication and division was restricted to the differences for school types. PMID:24133476

Isotope geochemistry of early Kilauea magmas from the submarine Hilina bench: The nature of the Hilina mantle component

USGS Publications Warehouse

Kimura, Jun-Ichi; Sisson, Thomas W.; Nakano, Natsuko; Coombs, Michelle L.; Lipman, Peter W.

2006-01-01

Submarine lavas recovered from the Hilina bench region, offshore Kilauea, Hawaii Island provide information on ancient Kilauea volcano and the geochemical components of the Hawaiian hotspot. Alkalic lavas, including nephelinite, basanite, hawaiite, and alkali basalt, dominate the earliest stage of Kilauea magmatism. Transitional basalt pillow lavas are an intermediate phase, preceding development of the voluminous tholeiitic subaerial shield and submarine Puna Ridge. Most alkalic through transitional lavas are quite uniform in Sr–Nd–Pb isotopes, supporting the interpretation that variable extent partial melting of a relatively homogeneous source was responsible for much of the geochemical diversity of early Kilauea magmas (Sisson et al., 2002). These samples are among the highest 206Pb/204Pb known from Hawaii and may represent melts from a distinct geochemical and isotopic end-member involved in the generation of most Hawaiian tholeiites. This end-member is similar to the postulated literature Kea component, but we propose that it should be renamed Hilina, to avoid confusion with the geographically defined Kea-trend volcanoes. Isotopic compositions of some shield-stage Kilauea tholeiites overlap the Hilina end-member but most deviate far into the interior of the isotopic field defined by magmas from other Hawaiian volcanoes, reflecting the introduction of melt contributions from both “Koolau” (high 87Sr/86Sr, low 206Pb/204Pb) and depleted (low 87Sr/86Sr, intermediate 206Pb/204Pb) source materials. This shift in isotopic character from nearly uniform, end-member, and alkalic, to diverse and tholeiitic corresponds with the major increase in Kilauea's magmatic productivity. Two popular geodynamic models can account for these relations: (1) The upwelling mantle source could be concentrically zoned in both chemical/isotopic composition, and in speed/extent of upwelling, with Hilina (and Loihi) components situated in the weakly ascending margins and the Koolau component in the interior. The depleted component could be refractory and spread throughout or scavenged from the overlying lithosphere. (2) The Hilina (and Loihi) components could be a more fertile material (lower melting temperature) spread irregularly throughout the Hawaiian source in a matrix of more refractory depleted and Koolau compositions. Modest upwelling along the leading hotspot margin melts the fertile domains predominantly, while the refractory matrix also partially melts in the more vigorously upwelling hotspot interior, diluting the Hilina and Loihi components and yielding voluminous isotopically diverse tholeiitic magmas.

discovery toolset for Emulytics v. 1.0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fritz, David; Crussell, Jonathan

The discovery toolset for Emulytics enables the construction of high-fidelity emulation models of systems. The toolset consists of a set of tools and techniques to automatically go from network discovery of operational systems to emulating those complex systems. Our toolset combines data from host discovery and network mapping tools into an intermediate representation that can then be further refined. Once the intermediate representation reaches the desired state, our toolset supports emitting the Emulytics models with varying levels of specificity based on experiment needs.

Phenylalanine 445 within oxidosqualene-lanosterol cyclase from Saccharomyces cerevisiae influences C-Ring cyclization and deprotonation reactions.

PubMed

Wu, Tung-Kung; Liu, Yuan-Ting; Chiu, Feng-Hsuan; Chang, Cheng-Hsiang

2006-10-12

[reaction: see text] We describe the Saccharomyces cerevisiae oxidosqualene-lanosterol cyclase Phe445 site-saturated mutants that generate truncated tricyclic and altered deprotonation product profiles. Among these mutants, only polar side-chain group substitutions genetically complemented yeast viability and produced spatially related product diversity, supporting the Johnson model that cation-pi interactions between a carbocationic intermediate and an enzyme can be replaced by an electrostatic or polar side chain to stabilize the cationic intermediate, but with product differentiation.

N,N-Diethylurea-Catalyzed Amidation between Electron-Defficient Aryl Azides and Phenylacetaldehydes

PubMed Central

Xie, Sheng; Ramström, Olof; Yan, Mingdi

2015-01-01

Urea structures, of which N,N-diethylurea (DEU) proved to be the most efficient, were discovered to catalyze amidation reactions between electron-defficient aryl azides and phenylacetaldehydes. Experimental data support 1,3-dipolar cycloaddition between DEU-activated enols and electrophilic phenyl azides, especially perfluoroaryl azides, followed by rearrangement of the triazoline intermediate. The activation of the aldehyde under near-neutral conditions was of special importance in inhibiting dehydration/aromatization of the triazoline intermediate, thus promoting the rearrangement to form aryl amides. PMID:25616121

Retrospective analysis of porcelain failures of metal ceramic crowns and fixed partial dentures supported by 729 implants in 152 patients: patient-specific and implant-specific predictors of ceramic failure.

PubMed

Kinsel, Richard P; Lin, Dongming

2009-06-01

Porcelain fracture associated with an implant-supported, metal ceramic crown or fixed partial denture occurs at a higher rate than in tooth-supported restorations, according to the literature. Implant-specific and patient-specific causes of ceramic failure have not been fully evaluated. The purpose of this retrospective study was to evaluate the potential statistical predictors for porcelain fracture of implant-supported, metal ceramic restorations. Over a 6-month period, a consecutive series of patients having previously received implant-supported, metal ceramic fixed restorations were examined during periodic recall appointments. The number of supporting implants, number of dental units, type of restoration, date of prosthesis insertion, location in the dental arch, opposing dentition, type of occlusion, presence of parafunctional habits, use of an occlusal protective device, presence or absence of ceramic fractures, gender, and age were recorded for each patient. The generalized estimating equation (GEE) approach was used for the intrasubject correlated measurements analysis of categorical outcomes (presence or absence of ceramic fractures) to determine which patient- and implant-specific factors would predict porcelain fracture (alpha=.05). Data were collected from 152 patients representing 998 dental units (390 single crowns and 94 fixed partial dentures) supported by 729 implants. Porcelain fractures of 94 dental units occurred in 35 patients. The fractures were significantly (P<.05) associated with opposing implant-supported metal ceramic restorations, bruxism, and not wearing a protective occlusal device. Metal ceramic prostheses (single crown or fixed partial dentures) had approximately 7 times higher odds of porcelain fracture (odds ratio (OR)=7.06; 95% confidence interval (CI): 2.57 to 19.37) and 13 times greater odds of a fracture requiring either repair or replacement (OR=13.95; 95% CI: 2.25 to 86.41) when in occlusion with another implant-supported restoration, as compared to opposing a natural tooth. In addition, patients exhibiting bruxism or not wearing an occlusal device had approximately 7 times higher odds (OR=7.23; 95% CI: 3.86 to 13.54), and 2 times higher odds (OR=1.92; 95% CI: 1.01 to 3.67) of porcelain fracture when compared to patients without bruxism and patients not wearing an occlusal device. Implant-supported metal ceramic single crowns and fixed partial dentures were found to have a significantly higher risk of porcelain fracture in patients with bruxism habits, when a protective occlusal device was not used, and when the restoration opposed another implant-supported metal ceramic restoration.

English Language Teaching Profile: Saudi Arabia.

ERIC Educational Resources Information Center

British Council, London (England). English Language and Literature Div.

The role and status of English in Saudi Arabia are examined, with attention directed to: (1) English within the education system; (2) teachers of English; (3) English outside the education system; (4) materials support; (5) British support for the teaching of English; and (6) English syllabi at intermediate, secondary, and higher education levels.…

CALUTRON STRUCTURE

DOEpatents

Price, D.

1958-09-01

An improved means is described for removably installing and supporting a collector pocket in a calutron. The salient feature of the invention is the support of the collector pocket by means of suspension bolts engaging the pocket at a point intermediate the top and bottom of the pocket, and having nuts so arranged that by turing the desired predetermined position.

Crystal structure of cathepsin A, a novel target for the treatment of cardiovascular diseases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schreuder, Herman A., E-mail: herman.schreuder@sanofi.com; Liesum, Alexander, E-mail: alexander.liesum@sanofi.com; Kroll, Katja, E-mail: katja.kroll@sanofi.com

2014-03-07

Graphical abstract: - Highlights: • The structures of active cathepsin A and the inactive precursor are very similar. • The only major difference is the absence of a 40 residue activation domain. • The termini of the active catalytic core are held together by a disulfide bond. • Compound 1 reacts with the catalytic Ser150, building a tetrahedral intermediate. • Compound 2 is cleaved by the enzyme and a fragment remained bound. - Abstract: The lysosomal serine carboxypeptidase cathepsin A is involved in the breakdown of peptide hormones like endothelin and bradykinin. Recent pharmacological studies with cathepsin A inhibitors inmore » rodents showed a remarkable reduction in cardiac hypertrophy and atrial fibrillation, making cathepsin A a promising target for the treatment of heart failure. Here we describe the crystal structures of activated cathepsin A without inhibitor and with two compounds that mimic the tetrahedral intermediate and the reaction product, respectively. The structure of activated cathepsin A turned out to be very similar to the structure of the inactive precursor. The only difference was the removal of a 40 residue activation domain, partially due to proteolytic removal of the activation peptide, and partially by an order–disorder transition of the peptides flanking the removed activation peptide. The termini of the catalytic core are held together by the Cys253–Cys303 disulfide bond, just before and after the activation domain. One of the compounds we soaked in our crystals reacted covalently with the catalytic Ser150 and formed a tetrahedral intermediate. The other compound got cleaved by the enzyme and a fragment, resembling one of the natural reaction products, was found in the active site. These studies establish cathepsin A as a classical serine proteinase with a well-defined oxyanion hole. The carboxylate group of the cleavage product is bound by a hydrogen-bonding network involving one aspartate and two glutamate side chains. This network can only form if at least half of the carboxylate groups involved are protonated, which explains the acidic pH optimum of the enzyme.« less

Relocation of Intermediate-depth Seismicity in the Relic Alboran Slab: Clustering and Relationship to Tearing and Dehydration Embrittlement.

NASA Astrophysics Data System (ADS)

Sun, M.; Bezada, M.

2017-12-01

Intermediate-depth seismicity outside active subduction zones is rare. However, there is a well-known occurrence of such events in a N-S elongated volume between Spain and Morocco, within what most researchers consider to be the relic Alboran slab. Partial subduction of, and tearing from the adjoining continental lithosphere have been suggested in this area. We investigate whether dehydration embrittlement or shear instability is more consistent with the Alboran intermediate depth seismicity by considering their location relative to the expected thermal structure and expected areas of high strain rate associated with thinning or tearing of the slab. We use a dense temporary seismograph deployment in Spain and Morocco to relocate 65 intermediate-depth events occurring between 2010 and 2013 in this region. The relocation procedure is realized by a grid-search approach that minimizes the normalized misfit between the picked times and travel times calculated using a regional 3D velocity model. Results indicate that, compared with catalog results, hypocenters after relocation are more concentrated in space; they tend to shift southward and eastward while no systematic shift in depth is observed. Relocated hypocenters concentrate at a depth range between 50-100 km and along a narrow longitude range around 4.5W. Investigation of the earthquake density distribution indicates these earthquakes concentrate into several clusters. One such cluster sits above the spain-arm of the Alboran slab and beneath the Spain continental lithosphere, indicating that it is likely associated to the thinning process of the Alboran slab. The other four clusters all lie within the interior of the slab. Interestingly, two of them are near the middle of the subducted lithosphere and the other two lie near its base. This observation seems at odds with expectations based on the two leading hypotheses for enabling brittle failure at intermediate depths.

Intermediate Pond Sizes Contain the Highest Density, Richness, and Diversity of Pond-Breeding Amphibians

PubMed Central

Semlitsch, Raymond D.; Peterman, William E.; Anderson, Thomas L.; Drake, Dana L.; Ousterhout, Brittany H.

2015-01-01

We present data on amphibian density, species richness, and diversity from a 7140-ha area consisting of 200 ponds in the Midwestern U.S. that represents most of the possible lentic aquatic breeding habitats common in this region. Our study includes all possible breeding sites with natural and anthropogenic disturbance processes that can be missing from studies where sampling intensity is low, sample area is small, or partial disturbance gradients are sampled. We tested whether pond area was a significant predictor of density, species richness, and diversity of amphibians and if values peaked at intermediate pond areas. We found that in all cases a quadratic model fit our data significantly better than a linear model. Because small ponds have a high probability of pond drying and large ponds have a high probability of fish colonization and accumulation of invertebrate predators, drying and predation may be two mechanisms driving the peak of density and diversity towards intermediate values of pond size. We also found that not all intermediate sized ponds produced many larvae; in fact, some had low amphibian density, richness, and diversity. Further analyses of the subset of ponds represented in the peak of the area distribution showed that fish, hydroperiod, invertebrate density, and canopy are additional factors that drive density, richness and diversity of ponds up or down, when extremely small or large ponds are eliminated. Our results indicate that fishless ponds at intermediate sizes are more diverse, produce more larvae, and have greater potential to recruit juveniles into adult populations of most species sampled. Further, hylid and chorus frogs are found predictably more often in ephemeral ponds whereas bullfrogs, green frogs, and cricket frogs are found most often in permanent ponds with fish. Our data increase understanding of what factors structure and maintain amphibian diversity across large landscapes. PMID:25906355

Efficacy and Safety of apatinib in patients with intermediate/advanced hepatocellular carcinoma: A prospective observation study.

PubMed

Yu, Wen-Chang; Zhang, Kong-Zhi; Chen, Shi-Guang; Liu, Wei-Fu

2018-01-01

This prospective study aimed to evaluate the efficacy and safety of apatinib in patients with intermediate/advanced hepatocellular carcinoma (HCC).The patients with intermediate/advanced HCC, who met predetermined inclusion and exclusion criteria, underwent oral treatment of apatinib 500 mg daily. The drug-related adverse effects were monitored by regular follow-up and workup including laboratory tests and imaging examinations. Tumor response was assessed by response evaluation criteria in solid tumor criteria. The time to tumor progression (TTP) and overall survival rate (OS) were calculated using the Kaplan-Meier method.A total of 31 patients were enrolled in the study from October 28, 2015 to December 28, 2016. The number of patients with intermediate and advanced HCC was 4 (12.90%) and 27 (87.10%), respectively. The mean tumor size was 9.47 ± 5.48 cm (range: 1.2-19 cm). Vascular invasion was seen in 14 patients (45.16%). A total of 21 (67.74%) patients exhibited extrahepatic metastases. On the basis of first follow-up computed tomography and magnetic resonance imaging at 6 weeks after treatment, 10 (32.26%), 15 (48.39%), and 6 (19.35%) of 31 patients achieved a partial response, stable disease, and progression of disease, respectively. Response rate and disease control rate were 32.26% and 80.65%, respectively. The median TTP was 4.8 months (95% confidence interval: 3.75-5.86 months). Furthermore, 6- and 12-month OS rates were 73.8% and 55.4%, respectively. Grade 3 thrombocytopenia (6.45%) and hypertension (48.39%) were the most common hematologic and nonhematologic toxicities. Grade 3 elevation of either serum total bilirubin or aminotransferase (6.45%) was observed as the top incidence among important indexes of liver function.Our preliminary findings suggest apatinib is a safe and effective therapy in intermediate/advanced HCC patients with high tumor response and survival rates. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

Efficacy and Safety of apatinib in patients with intermediate/advanced hepatocellular carcinoma: A prospective observation study

PubMed Central

Yu, Wen-Chang; Zhang, Kong-Zhi; Chen, Shi-Guang; Liu, Wei-Fu

2018-01-01

Abstract This prospective study aimed to evaluate the efficacy and safety of apatinib in patients with intermediate/advanced hepatocellular carcinoma (HCC). The patients with intermediate/advanced HCC, who met predetermined inclusion and exclusion criteria, underwent oral treatment of apatinib 500 mg daily. The drug-related adverse effects were monitored by regular follow-up and workup including laboratory tests and imaging examinations. Tumor response was assessed by response evaluation criteria in solid tumor criteria. The time to tumor progression (TTP) and overall survival rate (OS) were calculated using the Kaplan–Meier method. A total of 31 patients were enrolled in the study from October 28, 2015 to December 28, 2016. The number of patients with intermediate and advanced HCC was 4 (12.90%) and 27 (87.10%), respectively. The mean tumor size was 9.47 ± 5.48 cm (range: 1.2–19 cm). Vascular invasion was seen in 14 patients (45.16%). A total of 21 (67.74%) patients exhibited extrahepatic metastases. On the basis of first follow-up computed tomography and magnetic resonance imaging at 6 weeks after treatment, 10 (32.26%), 15 (48.39%), and 6 (19.35%) of 31 patients achieved a partial response, stable disease, and progression of disease, respectively. Response rate and disease control rate were 32.26% and 80.65%, respectively. The median TTP was 4.8 months (95% confidence interval: 3.75–5.86 months). Furthermore, 6- and 12-month OS rates were 73.8% and 55.4%, respectively. Grade 3 thrombocytopenia (6.45%) and hypertension (48.39%) were the most common hematologic and nonhematologic toxicities. Grade 3 elevation of either serum total bilirubin or aminotransferase (6.45%) was observed as the top incidence among important indexes of liver function. Our preliminary findings suggest apatinib is a safe and effective therapy in intermediate/advanced HCC patients with high tumor response and survival rates. PMID:29505026

Ligand Docking to Intermediate and Close-To-Bound Conformers Generated by an Elastic Network Model Based Algorithm for Highly Flexible Proteins

PubMed Central

Kurkcuoglu, Zeynep; Doruker, Pemra

2016-01-01

Incorporating receptor flexibility in small ligand-protein docking still poses a challenge for proteins undergoing large conformational changes. In the absence of bound structures, sampling conformers that are accessible by apo state may facilitate docking and drug design studies. For this aim, we developed an unbiased conformational search algorithm, by integrating global modes from elastic network model, clustering and energy minimization with implicit solvation. Our dataset consists of five diverse proteins with apo to complex RMSDs 4.7–15 Å. Applying this iterative algorithm on apo structures, conformers close to the bound-state (RMSD 1.4–3.8 Å), as well as the intermediate states were generated. Dockings to a sequence of conformers consisting of a closed structure and its “parents” up to the apo were performed to compare binding poses on different states of the receptor. For two periplasmic binding proteins and biotin carboxylase that exhibit hinge-type closure of two dynamics domains, the best pose was obtained for the conformer closest to the bound structure (ligand RMSDs 1.5–2 Å). In contrast, the best pose for adenylate kinase corresponded to an intermediate state with partially closed LID domain and open NMP domain, in line with recent studies (ligand RMSD 2.9 Å). The docking of a helical peptide to calmodulin was the most challenging case due to the complexity of its 15 Å transition, for which a two-stage procedure was necessary. The technique was first applied on the extended calmodulin to generate intermediate conformers; then peptide docking and a second generation stage on the complex were performed, which in turn yielded a final peptide RMSD of 2.9 Å. Our algorithm is effective in producing conformational states based on the apo state. This study underlines the importance of such intermediate states for ligand docking to proteins undergoing large transitions. PMID:27348230

Kinetics of proton uptake and dye binding by photoactive yellow protein in wild type and in the E46Q and E46A mutants.

PubMed

Borucki, Berthold; Devanathan, Savitha; Otto, Harald; Cusanovich, Michael A; Tollin, Gordon; Heyn, Maarten P

2002-08-06

We studied the kinetics of proton uptake and release by photoactive yellow protein (PYP) from Ectothiorhodospira halophila in wild type and the E46Q and E46A mutants by transient absorption spectroscopy with the pH-indicator dyes bromocresol purple or cresol red in unbuffered solution. In parallel, we investigated the kinetics of chromophore protonation as monitored by the rise and decay of the blue-shifted state I(2) (lambda(max) = 355 nm). For wild type the proton uptake kinetics is synchronized with the fast phase of I(2) formation (tau = 500 micros at pH 6.2). The transient absorption signal from the dye also contains a slower component which is not due to dye deprotonation but is caused by dye binding to a hydrophobic patch that is transiently exposed in the structurally changed and partially unfolded I(2) intermediate. This conclusion is based on the wavelength, pH, and concentration dependence of the dye signal and on dye measurements in the presence of buffer. SVD analysis, moreover, indicates the presence of two components in the dye signal: protonation and dye binding. The dye binding has a rise time of about 4 ms and is coupled kinetically with a transition between two I(2) intermediates. In the mutant E46Q, which lacks the putative internal proton donor E46, the formation of I(2) is accelerated, but the proton uptake kinetics remains kinetically coupled to the fast phase of I(2) formation (tau = 100 micros at pH 6.3). For this mutant the protein conformational change, as monitored by the dye binding, occurs with about the same time constant as in wild type but with reduced amplitude. In the alkaline form of the mutant E46A the formation of the I(2)-like intermediate is even faster as is the proton uptake (tau = 20 micros at pH 8.3). No dye binding occurred in E46A, suggesting the absence of a conformational change. In all of the systems proton release is synchronized with the decay of I(2). Our results support mechanisms in which the chromophore of PYP is protonated directly from the external medium rather than by the internal donor E46.

Computational analysis of aortic hemodynamics during total and partial extracorporeal membrane oxygenation and intra-aortic balloon pump support.

PubMed

Caruso, Maria Vittoria; Gramigna, Vera; Renzulli, Attilio; Fragomeni, Gionata

2016-01-01

The extracorporeal membrane oxygenation (ECMO) is a temporary, but prolonged circulatory support for cardiopulmonary failure. Clinical evidence suggests that pulsed flow is healthier than non pulsatile perfusion. The aim of this study was to computationally evaluate the effects of total and partial ECMO assistance and pulsed flow on hemodynamics in a patient-specific aorta model. The pulsatility was obtained by means of the intra-aortic balloon pump (IABP), and two different cases were investigated, considering a cardiac output (CO) of 5 L/min: Case A - total assistance - the whole flow delivered through the ECMO arterial cannula; Case B - partial assistance - flow delivered half through the cannula and half through the aorta. Computational fluid dynamic (CFD) analysis was carried out using the multiscale approach to couple the 3D aorta model with the lumped parameter model (resistance boundary condition). In case A pulsatility followed the balloon radius change, while in case B it was mostly influenced by the cardiac one. Furthermore, during total assistance, a blood stagnation occurred in the ascending aorta; in the case of partial assistance, the flow was orderly when the IABP was on and was chaotic when the balloon was off. Moreover, the mean arterial pressure (MAP) was higher in case B. The wall shear stress was worse in ascending aorta in case A. Partial support is hemodynamically advisable.

Social Relationships, Gender, and Recovery From Mobility Limitation Among Older Americans

PubMed Central

Clarke, Philippa J.; Pavela, Greg

2015-01-01

Objectives. Evidence suggests social relationships may be important facilitators for recovery from functional impairment, but the extant literature is limited in its measurement of social relationships including an over emphasis on filial social support and a paucity of nationally representative data. Methods. Using data from Waves 4–9 (1998–2008) of the Health and Retirement Study (HRS), this research examines the association between social relationships and recovery from severe mobility limitation (i.e., difficulty walking one block or across the room) among older Americans. Using a more nuanced measure of recovery that includes complete and partial recovery, a series of discrete-time event history models with multiple competing recovery outcomes were estimated using multinomial logistic regression. Results. Providing instrumental support to peers increased the odds of complete and partial recovery from severe mobility limitation, net of numerous social, and health factors. Having relatives living nearby decreased the odds of complete recovery, while being engaged in one’s neighborhood increased the odds of partial recovery. The influence of partner status on partial and complete recovery varied by gender, whereby partnered men were more likely to experience recovery relative to partnered women. The effect of neighborhood engagement on partial recovery also varied by gender. Disengaged women were the least likely to experience partial recovery compared with any other group. Discussion. The rehabilitative potential of social relationships has important policy implications. Interventions aimed at encouraging older adults with mobility limitation to be engaged in their neighborhoods and/or provide instrumental support to peers may improve functional health outcomes. PMID:25583597

Biomechanical evaluation of the natural abutment teeth in combined tooth-implant-supported telescopic prostheses: a three-dimensional finite element analysis.

PubMed

Chen, Yu; Wang, Chao; Huang, Yuanding; Feng, Tianming; Zou, Huawei; Fan, Yubo

2017-07-01

Telescopic overdentures supported by the combination of natural teeth and implants have been thought a valuable treatment for the severely compromised partially edentulous patients. But the combination of teeth and implants involves highly complex biomechanical problems. This study is to evaluate biomechanical behaviors of the natural abutment teeth with the treatment of combined tooth-implant supported telescopic crown prostheses in mandible through 3D FEA. According to this study, the prosthetic option supported by a combination of teeth and implants and retained by double crowns could protect teeth and their periodontal support tissues acting as a rigid splint, and may be a valuable treatment option for partially edentulous patients with severely reduced remaining teeth in mandible.

VISA/VRSA (Vancomycin-Intermediate/Resistant Staphylococcus aureus) in Healthcare Settings

MedlinePlus

... Personnel PPE Training Infection Control Assessment Tools Water Management Programs Map: HAI Prevention Activities Research CDC Supported Projects Prevention Epicenters (PE) Healthcare Safety Research (SHEPheRD) Environmental ...

Influence of length and diameter of implants associated with distal extension removable partial dentures.

PubMed

Verri, Fellippo Ramos; Pellizzer, Eduardo Piza; Rocha, Eduardo Passos; Pereira, João Antônio

2007-09-01

The aim of this study was to evaluate the influence of the length and diameter of the implant incorporated under the saddle of a distal-extension removable partial denture, acting as support. Six hemi-mandibular models were made with the presence of left inferior cuspid and first bicuspid, with the following differences: model A, without removable partial denture; model B, removable partial denture only; model C, removable partial denture and implant of 3.75 x x mm; model D, removable partial denture and implant of 3.75 x x3 mm; model E, removable partial denture and implant of 5 x x mm; and model F, removable partial denture and implant of 5 x x3 mm. These models were designed with the aid of AutoCAD 2000 (Autodesk, Inc., San Rafael, CA) and processed for finite element analysis by ANSYS 5.4 (Swanson Analysis Systems, Houston, PA). The loads applied were 50 N vertical on each cuspid point. It was noted that the presence of the removable partial denture overloaded the supporting tooth and other structures. The introduction of the implant reduced tensions, mainly at the extremities of the edentulous edge. Both the length and diameter tended to reduce tensions as their dimensions increased. Increasing the length of the implant had a great influence on the decrease of displacement and von Mises tension values. Increasing the diameter of the implant had a great influence on the decrease of von Mises tension values, but did not influence the displacement values. According to the results of this study, it is a good choice to use the greater and larger implant possible in the association between implant and distal extension removable partial denture.

Report on Partial Findings of an Ongoing Research: Social Networking Sites (SNS) as a Platform to Support Teaching and Learning in Secondary Schools

ERIC Educational Resources Information Center

Bt. Ubaidullah, Nor Hasbiah; Samsuddin, Khairulanuar; Bt. Fabil, Norsikin; Bt. Mahadi, Norhayati

2011-01-01

This paper reports the partial findings of a survey that was carried out in the analysis phase of an ongoing research for the development of a prototype of a Social Networking Site (SNS) to support teaching and learning in secondary schools. For the initial phase of the study, a quantitative research method was used based on a survey involving 383…

Treadmill training with partial body-weight support after anterior cruciate ligament reconstruction: a randomized controlled trial.

PubMed

Luo, Yuan; Shen, Weizhong; Jiang, Zhong; Sha, Jiao

2016-12-01

[Purpose] To compare the effects of treadmill training with partial body weight support (TTPBWS) and conventional physical therapy (PT) on subjects with anterior cruciate ligament reconstructions. [Subjects and Methods] A total of 40 subjects were randomly allocated to either a treatment group or a control group. Subjects received either treadmill training with partial body weight support (treatment group) or conventional physical therapy (control group). The circumferences of the lower extremities, Holden classifications, 10-meter walking times and the International Knee Documentation Committee (IKDC) scores were compared at 12 and 24 weeks post-operation. The knee joint stability was tested at 24 weeks post-operation using a KT-1000. [Results] Significant differences were found between the two groups at the 12 weeks post-operation. For most of the measures, there was no significant difference between the groups at 24 weeks post-operation. Interestingly, for most of the measures, there was no significant difference between their values in the treatment group at 12 weeks and their values in the control group at 24 weeks post-operation. [Conclusion] The function of a subject's lower extremities can be improved and the improvement was clearly accelerated by the intervention of treadmill training with partial body weight support, without compromising the stability of the knee joints in a given follow-up period.

Perceived discrimination and antisocial behaviour among Chinese rural-to-urban migrant adolescents: Mediating effects of social support.

PubMed

Jia, Xuji; Liu, Xia

2017-08-01

Using cross-sectional data from rural-to-urban migrant adolescents in urban areas of Beijing, China, we examined the mediating effects of social support (i.e. teacher support and classmate support) in the relationship between perceived discrimination (PD) and antisocial behaviour (ASB) among Chinese migrant adolescents. Participants were 897 adolescents (459 boys and 438 girls, mean age = 13.34 years) from four migrant schools (68.8%) and four public schools (31.2%). Participants completed self-report questionnaires concerning PD, ASB, teacher support and classmate support. Results indicated that Chinese migrant adolescents who perceived more discrimination were more likely to engage in ASB. Teacher support partially mediated the relationship between PD and ASB. Gender moderated this mediational relationship, such that teacher support exerted a mediating role among girls, but not boys. The findings suggest that reductions in teacher support may partially account for the effect of PD on ASB among Chinese migrant adolescents girls. © 2016 International Union of Psychological Science.

The reaction of indole with the aminoacrylate intermediate of Salmonella typhimurium tryptophan synthase: observation of a primary kinetic isotope effect with 3-[(2)H]indole.

PubMed

Cash, Michael T; Miles, Edith W; Phillips, Robert S

2004-12-15

The bacterial tryptophan synthase alpha(2)beta(2) complex catalyzes the final reactions in the biosynthesis of L-tryptophan. Indole is produced at the active site of the alpha-subunit and is transferred through a 25-30 A tunnel to the beta-active site, where it reacts with an aminoacrylate intermediate. Lane and Kirschner proposed a two-step nucleophilic addition-tautomerization mechanism for the reaction of indole with the aminoacrylate intermediate, based on the absence of an observed kinetic isotope effect (KIE) when 3-[(2)H]indole reacts with the aminoacrylate intermediate. We have now observed a KIE of 1.4-2.0 in the reaction of 3-[(2)H]indole with the aminoacrylate intermediate in the presence of monovalent cations, but not when an alpha-subunit ligand, disodium alpha-glycerophosphate (Na(2)GP), is present. Rapid-scanning stopped flow kinetic studies were performed of the reaction of indole and 3-[(2)H]indole with tryptophan synthase preincubated with L-serine, following the decay of the aminoacrylate intermediate at 350 nm, the formation of the quinonoid intermediate at 476 nm, and the formation of the L-Trp external aldimine at 423 nm. The addition of Na(2)GP dramatically slows the rate of reaction of indole with the alpha-aminoacrylate intermediate. A primary KIE is not observed in the reaction of 3-[(2)H]indole with the aminoacrylate complex of tryptophan synthase in the presence of Na(2)GP, suggesting binding of indole with tryptophan synthase is rate limiting under these conditions. The reaction of 2-methylindole does not show a KIE, either in the presence of Na(+) or Na(2)GP. These results support the previously proposed mechanism for the beta-reaction of tryptophan synthase, but suggest that the rate limiting step in quinonoid intermediate formation from indole and the aminoacrylate intermediate is deprotonation.

[Psychosocial rehabilitation at the dawn of the 21st century: II: Therapeutic or rehabilitative modalities and institutional disposition].

PubMed

Gasset, François; Orita, Alina; Spagnoli, Dany; Pomini, Valentino; Rabia, Sophie; Ducret, Michel; Veillon, Henri; Cucchia, Anne-Therèse

2004-04-01

The main goal of psychosocial rehabilitation is to compensate the vulnerability underlying psychiatric disorders through intermediate institutions when the persistence and recurrence of these disorders have led to social and professional exclusion. Intermediate institutions refer to services which allow transition between the state of dependence on the hospital to the state of relative autonomy in social community. Psychosocial rehabilitation is a comprehensive approach which link the type of interventions: treatment, rehabilitation and support integrated in multimodal and individualized programs. A study of the out-patients followed by the rehabilitation unit of the psychiatric department in Lausanne has shown that provision of services is divided into 60% for rehabilitation, 20% for treatment and 20% for support independently of the psychiatric disorders. The implementation of these programs necessitates institutional support from psychiatric hospital to outpatient clinics through different types of facilities in order to offer a medical and psychosocial device of rehabilitation into the community.

Adsorption and oxidation of formaldehyde on a polycrystalline Pt film electrode: An in situ IR spectroscopy search for adsorbed reaction intermediates

PubMed Central

Behm, R Jürgen

2014-01-01

Summary As part of a mechanistic study of the electrooxidation of C1 molecules we have systematically investigated the dissociative adsorption/oxidation of formaldehyde on a polycrystalline Pt film electrode under experimental conditions optimizing the chance for detecting weakly adsorbed reaction intermediates. Employing in situ IR spectroscopy in an attenuated total reflection configuration (ATR-FTIRS) with p-polarized IR radiation to further improve the signal-to-noise ratio, and using low reaction temperatures (3 °C) and deuterium substitution to slow down the reaction kinetics and to stabilize weakly adsorbed reaction intermediates, we could detect an IR absorption band at 1660 cm−1 characteristic for adsorbed formyl intermediates. This assignment is supported by an isotope shift in wave number. Effects of temperature, potential and deuterium substitution on the formation and disappearance of different adsorbed species (COad, adsorbed formate, adsorbed formyl), are monitored and quantified. Consequences on the mechanism for dissociative adsorption and oxidation of formaldehyde are discussed. PMID:24991512

Electrochemical oxidation of quinoline aqueous solution on β-PbO2 anode and the evolution of phytotoxicity on duckweed.

PubMed

Ma, Xiangjuan; Bian, Lixia; Ding, Jingfeng; Wu, Yaping; Xia, Huilong; Li, Jionghui

2017-04-01

Electrochemical oxidation of quinoline on a β-PbO 2 electrode modified with fluoride resin and the comprehensive toxicity of intermediates formed during oxidation on duckweed were investigated in detail. The results showed that quinoline was initially hydroxylated at the C-2 and C-8 positions by hydroxyl radicals (·OH) electro-generated on a β-PbO 2 anode, yielding 2(1H)-quinolinone and 8-hydroxyquinoline, then undergoing ring cleavage to form pyridine, nicotinic acid, pyridine-2-carboxaldehyde and acetophenone, which were ultimately converted to biodegradable organic acids. NO 3 - was the final form of quinoline-N. The growth of duckweed exposed to the oxidized quinoline solution was gradually inhibited with the decrease in pH and the formation of intermediates. However, the growth inhibition of duckweed could be eliminated beyond 120 min of oxidation, indicating the comprehensive toxicity of the quinoline solution reduced when the amount of quinoline removed was above 80%. Additionally, the adjustment of the pH to 7.5 and the addition of nutrients to the treated quinoline solution before culturing duckweed could obviously alleviate the inhibition on duckweed. Thus, partial electrochemical degradation of quinoline offers a cost-effective and clean alternative for pretreatment of wastewater containing nitrogen-heterocyclic compounds before biological treatment. The duckweed test presents a simple method for assessing the comprehensive toxicity of intermediates.

Shoe drop reduction influences the lower limb biomechanics of children tennis players during an open stance forehand: A longitudinal study.

PubMed

Herbaut, Alexis; Simoneau-Buessinger, Emilie; Barbier, Franck; Gillet, Christophe; Roux, Maxime; Guéguen, Nils; Chavet, Pascale

2017-11-01

Compared to traditional tennis shoes, using 0-drop shoes was shown to induce an immediate switch from rear- to forefoot strike pattern to perform an open stance tennis forehand for 30% of children tennis players. The purpose of the study was to examine the long-term effects of a gradual reduction in the shoe drop on the biomechanics of children tennis players performing open stance forehands. Thirty children tennis players participated in 2 laboratory biomechanical test sessions (intermediate: +4 months and final: +8 months) after an inclusion visit where they were randomly assigned to control (CON) or experimental (EXP) group. CON received 12-mm-drop shoes twice, whereas EXP received 8 mm then 4-mm-drop shoes. Strike index indicated that all CON were rearfoot strikers in intermediate and final test sessions. All EXP were rearfoot strikers in intermediate test session, but half the group switched towards a forefoot strike pattern in final test session. This switch resulted in a decreased loading rate of the ground reaction force (-73%, p = .005) but increased peak ankle plantarflexors moment (+47%, p = .050) and peak ankle power absorption (+107%, p = .005) for these participants compared with CON. Biomechanical changes associated with the long-term use of partial minimalist shoes suggest a reduction in heel compressive forces but an increase in Achilles tendon tensile forces.

In-Situ and Real-time Monitoring of Mechanochemical Preparation of Li2 Mg(NH2 BH3 )4 and Na2 Mg(NH2 BH3 )4 and Their Thermal Dehydrogenation.

PubMed

Biliškov, Nikola; Borgschulte, Andreas; Užarević, Krunoslav; Halasz, Ivan; Lukin, Stipe; Milošević, Sanja; Milanović, Igor; Novaković, Jasmina Grbović

2017-11-16

For the first time, in situ monitoring of uninterrupted mechanochemical synthesis of two bimetallic amidoboranes, M 2 Mg(NH 2 BH 3 ) 4 (M=Li, Na), by means of Raman spectroscopy, has been applied. This approach allowed real-time observation of key intermediate phases, and a straightforward follow-up of the reaction course. Detailed analysis of time-dependent spectra revealed a two-step mechanism through MNH 2 BH 3 ⋅NH 3 BH 3 adducts as key intermediate phases which further reacted with MgH 2 , giving M 2 Mg(NH 2 BH 3 ) 4 as final products. The intermediates partially take a competitive pathway toward the oligomeric M(BH 3 NH 2 BH 2 NH 2 BH 3 ) phases. The crystal structure of the novel bimetallic amidoborane Li 2 Mg(NH 2 BH 3 ) 4 was solved from high-resolution powder diffraction data and showed an analogous metal coordination to Na 2 Mg(NH 2 BH 3 ) 4 , but a significantly different crystal packing. Li 2 Mg(NH 2 BH 3 ) 4 thermally dehydrogenates releasing highly pure H 2 in the amount of 7 wt.%, and at a lower temperature then its sodium analogue, making it significantly more viable for practical applications. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

First detection of Echinococcus multilocularis in rodent intermediate hosts in Turkey.

PubMed

Avcioglu, Hamza; Guven, Esin; Balkaya, Ibrahim; Kirman, Ridvan; Bia, Mohammed Mebarek; Gulbeyen, Hatice; Kurt, Ali; Yaya, Sali; Demirtas, Sadik

2017-11-01

Echinococcus multilocularis is the causative agent of alveolar echinococcosis (AE), a potentially fatal zoonotic disease. Large parts of Turkey are considered as endemic for E. multilocularis. The aim of this study was to determine the occurrence of metacestode of E. multilocularis in wild rodents in Erzurum, an endemic region for human AE in Turkey. During the sampling period, a total of 498 rodents were trapped in twenty counties of Erzurum Province. Suspected lesions were observed on the livers of 48 rodents, and then partial fragment of mitochondrial 12S rRNA gene was PCR-amplified. Five liver samples exhibited E. multilocularis infection. The prevalence of E. multilocularis for Microtus spp. was 1·3%. All of the infected rodents had fertile metacestodes. Infected rodents were morphologically and molecularly analysed and were confirmed to be Microtus irani by the mitochondrial cytochrome b gene sequence analysis. This is the first report of the presence of E. multilocularis in rodent intermediate hosts in Turkey. Our findings of infected M. irani with protoscoleces show that this rodent can act as suitable intermediate host for E. multilocularis' life cycle in Turkey. However, there was a complete lack of data on the infection of carnivores from the country. An extensive survey is recommended to determine the prevalence of E. multilocularis in definitive hosts in this endemic region.

V x In (2–x) S 3 Intermediate Band Absorbers Deposited by Atomic Layer Deposition

DOE PAGES

McCarthy, Robert F.; Weimer, Matthew S.; Haasch, Richard T.; ...

2016-03-21

Substitutional alloys of several thin film semiconductors have been proposed as intermediate band (IB) materials for use in next-generation photovoltaics, which aim to utilize a larger fraction of the solar spectrum without sacrificing significant photovoltage. Here, we demonstrate a novel approach to IB material growth, namely atomic layer deposition (ALD), to enable unique control over substitutional-dopant location and density. Two new ALD processes for vanadium sulfide incorporation are introduced, one of which incorporates a vanadium (III) amidinate previously untested for ALD. We synthesize the first thin film V xIn (2-x)S 3 intermediate band semiconductors, using this process, and further demonstratemore » that the V:In ratio, and therefore intraband gap density of states, can be finely tuned according to the ALD dosing schedule. Deposition on a crystalline In 2S 3 underlayer promotes the growth of a tetragonal β-In 2S 3-like phase V xIn (2-x)S 3, which exhibits a distinct sub-band gap absorption peak with onset near 1.1 eV in agreement with computational predictions. But, the V xIn (2-x)S 3 films lack the lower energy transition predicted for a partially filled IB, and photoelectrochemical devices reveal a photocurrent response only from illumination with energy sufficient to span the parent band-gap.« less

Parenting Stress and Parent Support Among Mothers With High and Low Education

PubMed Central

2015-01-01

Current theorizing and evidence suggest that parenting stress might be greater among parents from both low and high socioeconomic positions (SEP) compared with those from intermediate levels because of material hardship among parents of low SEP and employment demands among parents of high SEP. However, little is known about how this socioeconomic variation in stress relates to the support that parents receive. This study explored whether variation in maternal parenting stress in a population sample was associated with support deficits. To obtain a clearer understanding of support deficits among mothers of high and low education, we distinguished subgroups according to mothers’ migrant and single-parent status. Participants were 5,865 mothers from the Growing Up in Scotland Study, who were interviewed when their children were 10 months old. Parenting stress was greater among mothers with either high or low education than among mothers with intermediate education, although it was highest for those with low education. Support deficits accounted for around 50% of higher stress among high- and low-educated groups. Less frequent grandparent contact mediated parenting stress among both high- and low-educated mothers, particularly migrants. Aside from this common feature, different aspects of support were relevant for high- compared with low-educated mothers. For high-educated mothers, reliance on formal childcare and less frequent support from friends mediated higher stress. Among low-educated mothers, smaller grandparent and friend networks and barriers to professional parent support mediated higher stress. Implications of differing support deficits are discussed. PMID:26192130

Working while on a disability pension in Finland: Association of diagnosis and financial factors to employment.

PubMed

Polvinen, Anu; Laaksonen, Mikko; Rantala, Juha; Hietaniemi, Marjukka; Kannisto, Jari; Kuivalainen, Susan

2018-02-01

The aim of this study was to find out whether health and financial factors are associated with engagement in paid work during a disability pension. The data included a 10 per cent sample of Finns aged 20-62 years who were drawing earnings-related full or partial disability pension in 2012 ( n = 14,418). Logistic regression analysis was used to estimate odds ratios for working while on a full or partial disability pension. Fourteen per cent of full disability pensioners and 76 per cent of partial disability pensioners were engaged in paid work. Full disability pensioners due to mental disorders were working less often than full disability pensioners due to other diseases. Partial disability pensioners due to cardiovascular diseases were working more than partial disability pensioners due to other diseases. More recent timing of disability pension was associated with working for both partial and full disability pensioners. Working while on disability pension was more common among those with higher education. Partial disability pensioners with average pension worked more often than those with high pension. By knowing the factors associated with working while on a disability pension, policies could be more efficiently allocated to encourage disability pensioners to take up work. One way would be to support disability pensioners with low education to work more. Another way to increase work among disability pensioners is to support the recently retired in working longer.

Methane to methanol conversion induced by thorium oxide through the CH3Th(O)H intermediate in solid argon.

PubMed

Gong, Yu; Andrews, Lester; Jackson, Virgil E; Dixon, David A

2012-10-15

Reactions of ThO molecules and CH(4) have been investigated in solid argon near 4 K. The CH(3)Th(O)H molecule is produced when the sample is exposed to UV irradiation. Identification of this new intermediate is substantiated by observation of the Th═O and Th-H stretching vibrational modes with isotopic substitution via matrix infrared spectroscopy, and the assignments are supported by electronic structure frequency calculations. Methanol absorptions increase together with formation of the CH(3)Th(O)H molecule, suggesting a methane to methanol conversion induced by thorium oxide proceeding through the CH(3)Th(O)H intermediate. The formation of CH(3)Th(O)H from ThO + CH(4) is exothermic (ΔH(rxn) = -11 kcal/mol) with an energy barrier of 30 kcal/mol at the CCSD(T)//B3LYP level. Decomposition of this intermediate to form methanol involves spin crossing, and the overall reaction from the intermediate is endothermic by 127 kcal/mol. There is no activation energy for the reaction of thorium atoms with methanol to give CH(3)Th(O)H, as observed in separate experiments with Th and CH(3)OH.

Vector-like quarks and leptons, SU(5) ⊗ SU(5) grand unification, and proton decay

NASA Astrophysics Data System (ADS)

Lee, Chang-Hun; Mohapatra, Rabindra N.

2017-02-01

SU(5) ⊗ SU(5) provides a minimal grand unification scheme for fermions and gauge forces if there are vector-like quarks and leptons in nature. We explore the gauge coupling unification in a non-supersymmetric model of this type, and study its implications for proton decay. The properties of vector-like quarks and intermediate scales that emerge from coupling unification play a central role in suppressing proton decay. We find that in this model, the familiar decay mode p → e +π0 may have a partial lifetime within the reach of currently planned experiments.

Weak η production off the nucleon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alam, M. Rafi; Athar, M. Sajjad; Alvarez-Ruso, L.

2015-05-15

The weak η-meson production off the nucleon induced by (anti)neutrinos is studied at low and intermediate energies, the range of interest for several ongoing and future neutrino experiments. We consider Born diagrams and the excitation of N{sup *} (1535)S{sub 11} and N{sup *} (1650)S{sub 11} resonances. The vector part of the N-S{sub 11} transition form factors has been obtained from the MAID helicity amplitudes while the poorly known axial part is constrained with the help of the partial conservation of the axial current (PCAC) and assuming the pion-pole dominance of the pseudoscalar form factor.

Suicide inactivation of cytochrome P-450 by methoxsalen. Evidence for the covalent binding of a reactive intermediate to the protein moiety

DOE Office of Scientific and Technical Information (OSTI.GOV)

Labbe, G.; Descatoire, V.; Beaune, P.

Incubation of rat liver microsomes with (3H)methoxsalen and NADPH resulted in the covalent binding of a methoxsalen intermediate to proteins comigrating with cytochromes P-450 UT-A, PB-B/D, ISF-G and PCN-E. Binding was increased by pretreatments with phenobarbital, beta-naphthoflavone (beta NF) and dexamethasone. Such pretreatments also increased the loss of CO-binding capacity either after administration of methoxsalen, or after incubation of hepatic microsomes with methoxsalen and NADPH. Immunoprecipitation of the methoxsalen metabolite-protein adducts in phenobarbital-induced microsomes was moderate with anti-UT-A antibodies, but marked with anti-PB-B/D and anti-PCN-E antibodies. Immunoprecipitation was observed also with anti-ISF-G (anti-beta NF-B) antibodies in beta NF-induced microsomes. Methoxsalenmore » (0.25 mM) inhibited markedly the benzphetamine demethylase activity of phenobarbital-induced microsomes and the erythromycin demethylase activity of dexamethasone-induced microsomes. Whereas methoxsalen itself did not produce any binding spectrum, in contrast either in vivo administration of methoxsalen or incubation in vitro with methoxsalen and NADPH resulted in a low-to-high spin conversion of cytochrome P-450 as suggested by the appearance of a spectrum analogous to a type I binding spectrum. This low-to-high spin conversion was apparently due to a methoxsalen intermediate (probably, covalently bound to the protein and preventing partial sixth ligation of the iron). We conclude that suicide inactivation of cytochrome P-450 by methoxsalen is related to the covalent binding of a methoxsalen intermediate to the protein moiety of several cytochrome P-450 isoenzymes (including UT-A, PB-B/D, PCN-E as well as ISF-G and/or beta NF-B).« less

Multiple-probe analysis of folding and unfolding pathways of human serum albumin. Evidence for a framework mechanism of folding.

PubMed

Santra, Manas Kumar; Banerjee, Abhijit; Krishnakumar, Shyam Sundar; Rahaman, Obaidur; Panda, Dulal

2004-05-01

The changes in the far-UV CD signal, intrinsic tryptophan fluorescence and bilirubin absorbance showed that the guanidine hydrochloride (GdnHCl)-induced unfolding of a multidomain protein, human serum albumin (HSA), followed a two-state process. However, using environment sensitive Nile red fluorescence, the unfolding and folding pathways of HSA were found to follow a three-state process and an intermediate was detected in the range 0.25-1.5 m GdnHCl. The intermediate state displayed 45% higher fluorescence intensity than that of the native state. The increase in the Nile red fluorescence was found to be due to an increase in the quantum yield of the HSA-bound Nile red. Low concentrations of GdnHCl neither altered the binding affinity of Nile red to HSA nor induced the aggregation of HSA. In addition, the secondary structure of HSA was not perturbed during the first unfolding transition (<1.5 m GdnHCl); however, the secondary structure was completely lost during the second transition. The data together showed that the half maximal loss of the tertiary structure occurred at a lower GdnHCl concentration than the loss of the secondary structure. Further kinetic studies of the refolding process of HSA using multiple spectroscopic techniques showed that the folding occurred in two phases, a burst phase followed by a slow phase. An intermediate with native-like secondary structure but only a partial tertiary structure was found to form in the burst phase of refolding. Then, the intermediate slowly folded into the native state. An analysis of the refolding data suggested that the folding of HSA could be best explained by the framework model.

INTEGRATED MODULATION OF PHORBOL ESTER-INDUCED RAF ACTIVATION IN EL4 LYMPHOMA CELLS

PubMed Central

Han, Shujie; Meier, Kathryn E.

2009-01-01

The EL4 murine lymphoma cell line exists in variant phenotypes that differ with respect to responses to the tumor promoter phorbol 12-myristate 13-acetate (PMA1). Previous work showed that “PMA-sensitive” cells, characterized by a high magnitude of PMA-induced Erk activation, express RasGRP, a phorbol ester receptor that directly activates Ras. In “PMA-resistant” and “intermediate” EL4 cell lines, PMA induces Erk activation to lesser extents, but with a greater response in intermediate cells. In the current study, these cell lines were used to examine mechanisms of Raf-1 modulation. Phospho-specific antibodies were utilized to define patterns and kinetics of Raf-1 phosphorylation on several sites. Further studies showed that Akt is constitutively activated to a greater extent in PMA-resistant than in PMA-sensitive cells, and also to a greater extent in resistant than intermediate cells. Akt negatively regulates Raf-1 activation (Ser259), partially explaining the difference between resistant and intermediate cells. Erk activation exerts negative feedback on Raf-1 (Ser289/296/301), thus resulting in earlier termination of the signal in cells with a higher level of Erk activation. RKIP, a Raf inhibitory protein, is expressed at higher levels in resistant cells than in sensitive or intermediate cells. Knockdown of RKIP increases Erk activation and also negative feedback. In conclusion, this study delineates Raf-1 phosphorylation events occurring in response to PMA in cell lines with different extents of Erk activation. Variations in the levels of expression and activation of multiple signaling proteins work in an integrated fashion to modulate the extent and duration of Erk activation. PMID:19263515

The most prevalent genetic cause of ALS-FTD, C9orf72 synergizes the toxicity of ATXN2 intermediate polyglutamine repeats through the autophagy pathway

PubMed Central

Ciura, Sorana; Sellier, Chantal; Campanari, Maria-Letizia; Charlet-Berguerand, Nicolas; Kabashi, Edor

2016-01-01

ABSTRACT The most common genetic cause for amyotrophic lateral sclerosis and frontotemporal dementia (ALS-FTD) is repeat expansion of a hexanucleotide sequence (GGGGCC) within the C9orf72 genomic sequence. To elucidate the functional role of C9orf72 in disease pathogenesis, we identified certain molecular interactors of this factor. We determined that C9orf72 exists in a complex with SMCR8 and WDR41 and that this complex acts as a GDP/GTP exchange factor for RAB8 and RAB39, 2 RAB GTPases involved in macroautophagy/autophagy. Consequently, C9orf72 depletion in neuronal cultures leads to accumulation of unresolved aggregates of SQSTM1/p62 and phosphorylated TARDBP/TDP-43. However, C9orf72 reduction does not lead to major neuronal toxicity, suggesting that a second stress may be required to induce neuronal cell death. An intermediate size of polyglutamine repeats within ATXN2 is an important genetic modifier of ALS-FTD. We found that coexpression of intermediate polyglutamine repeats (30Q) of ATXN2 combined with C9orf72 depletion increases the aggregation of ATXN2 and neuronal toxicity. These results were confirmed in zebrafish embryos where partial C9orf72 knockdown along with intermediate (but not normal) repeat expansions in ATXN2 causes locomotion deficits and abnormal axonal projections from spinal motor neurons. These results demonstrate that C9orf72 plays an important role in the autophagy pathway while genetically interacting with another major genetic risk factor, ATXN2, to contribute to ALS-FTD pathogenesis. PMID:27245636

The most prevalent genetic cause of ALS-FTD, C9orf72 synergizes the toxicity of ATXN2 intermediate polyglutamine repeats through the autophagy pathway.

PubMed

Ciura, Sorana; Sellier, Chantal; Campanari, Maria-Letizia; Charlet-Berguerand, Nicolas; Kabashi, Edor

2016-08-02

The most common genetic cause for amyotrophic lateral sclerosis and frontotemporal dementia (ALS-FTD) is repeat expansion of a hexanucleotide sequence (GGGGCC) within the C9orf72 genomic sequence. To elucidate the functional role of C9orf72 in disease pathogenesis, we identified certain molecular interactors of this factor. We determined that C9orf72 exists in a complex with SMCR8 and WDR41 and that this complex acts as a GDP/GTP exchange factor for RAB8 and RAB39, 2 RAB GTPases involved in macroautophagy/autophagy. Consequently, C9orf72 depletion in neuronal cultures leads to accumulation of unresolved aggregates of SQSTM1/p62 and phosphorylated TARDBP/TDP-43. However, C9orf72 reduction does not lead to major neuronal toxicity, suggesting that a second stress may be required to induce neuronal cell death. An intermediate size of polyglutamine repeats within ATXN2 is an important genetic modifier of ALS-FTD. We found that coexpression of intermediate polyglutamine repeats (30Q) of ATXN2 combined with C9orf72 depletion increases the aggregation of ATXN2 and neuronal toxicity. These results were confirmed in zebrafish embryos where partial C9orf72 knockdown along with intermediate (but not normal) repeat expansions in ATXN2 causes locomotion deficits and abnormal axonal projections from spinal motor neurons. These results demonstrate that C9orf72 plays an important role in the autophagy pathway while genetically interacting with another major genetic risk factor, ATXN2, to contribute to ALS-FTD pathogenesis.

Continental lithospheric subduction and intermediate-depth seismicity: Constraints from S-wave velocity structures in the Pamir and Hindu Kush

NASA Astrophysics Data System (ADS)

Li, Wei; Chen, Yun; Yuan, Xiaohui; Schurr, Bernd; Mechie, James; Oimahmadov, Ilhomjon; Fu, Bihong

2018-01-01

The Pamir has experienced more intense deformation and shortening than Tibet, although it has a similar history of terrane accretion. Subduction as a primary way to accommodate lithospheric shortening beneath the Pamir has induced the intermediate-depth seismicity, which is rare in Tibet. Here we construct a 3D S-wave velocity model of the lithosphere beneath the Pamir by surface wave tomography using data of the TIPAGE (Tien Shan-Pamir Geodynamic program) and other seismic networks in the area. We imaged a large-scale low velocity anomaly in the crust at 20-50 km depth in the Pamir overlain by a high velocity anomaly at a depth shallower than 15 km. The high velocity anomalies colocate with exposed gneiss domes, which may imply a similar history of crustal deformation, partial melting and exhumation in the hinterland, as has occurred in the Himalaya/Tibet system. At mantle depths, where the intermediate-depth earthquakes are located, a low velocity zone is clearly observed extending to about 180 km and 150 km depth in the Hindu Kush and eastern Pamir, respectively. Moreover, the geometry of the low-velocity anomaly suggests that lower crustal material has been pulled down into the mantle by the subducting Asian and Indian lithospheric mantle beneath the Pamir and Hindu Kush, respectively. Metamorphic processes in the subducting lower crust may cause the intermediate-depth seismicity down to 150-180 km depth beneath the Pamir and Hindu Kush. We inverted focal mechanisms in the seismic zone for the stress field. Differences in the stress field between the upper and lower parts of the Indian slab imply that subduction and detachment of the Indian lithosphere might cause intense seismicity associated with the thermal shear instability in the deep Hindu Kush.

Analysis and design of composite slab by varying different parameters

NASA Astrophysics Data System (ADS)

Lambe, Kedar; Siddh, Sharda

2018-03-01

Composite deck slabs are in demand because of its faster, lighter and economical construction work. Composite slab consists of cold formed deck profiled sheet and concrete either lightweight or normal. Investigation of shear behaviour of the composite slab is very complex. Shear bond strength depends on the various parameter such as a shape of sheeting, a thickness of the sheet, type of embossment and its frequency of use, shear stiffener or intermediate stiffener, type of load, an arrangement of load, length of shear span, the thickness of concrete and support friction etc. In present study finite element analysis is carried out with ABAQUS 6.13, a simply supported composite slab is considered for the investigation of the shear bond behaviour of the composite slab by considering variation in three different parameters, the shape of a sheet, thickness of sheet and shear span. Different shear spans of two different shape of cold formed deck profiled sheet i.e. with intermediate stiffeners and without intermediate stiffeners are considered with two different thicknesses (0.8 mm and 1.2 mm) for simulation. In present work, simulation of models has done for static loading with 20 mm mesh size is considered.

Glycerol electro-oxidation on a carbon-supported platinum catalyst at intermediate temperatures

NASA Astrophysics Data System (ADS)

Ishiyama, Keisuke; Kosaka, Fumihiko; Shimada, Iori; Oshima, Yoshito; Otomo, Junichiro

2013-03-01

The electro-oxidation of glycerol on a carbon-supported platinum catalyst (Pt/C) in combination with a reaction products analysis was investigated at intermediate temperatures (235-260 °C) using a single cell with a CsH2PO4 proton conducting solid electrolyte. A high current density was achieved. The main products were H2, CO2 and CO but the formation of C2 compounds, such as glycolic acid and ethane, was also observed. In addition, several C3 compounds were detected as minor products. A reaction products analysis revealed that the C-C bond dissociation ratio of glycerol was 70-80% at both low and high potentials (>200 mV vs. reversible hydrogen electrode) at 250 °C, suggesting that rapid dissociation occurs on Pt/C. The reaction products analysis also suggested that hydrogen production via thermal decomposition and/or steam reforming of glycerol (indirect path) and direct electro-oxidation of glycerol (direct path) proceed in parallel. More detailed reaction paths involving C1, C2 and C3 reaction products are discussed as well as the possible rate-determining step in glycerol electro-oxidation at intermediate temperatures.

Evaluation of Supported Placements in Integrated Community Environments Project (SPICE). Executive Summary of the Final Report.

ERIC Educational Resources Information Center

Wilson, Leslie; And Others

This executive summary presents highlights of a study which sought to determine whether participants in the Supported Placements in Integrated Community Environments project were better off after moving to community homes from intermediate care facilities and skilled nursing facilities, and to determine the variables that contribute to quality…

Living Independently in a Home and Community of Choice: How?

ERIC Educational Resources Information Center

Braswell, Gail; Ritter, Linda; Sufficool, Mary Jane

2009-01-01

Residents in a group home, supported apartment, or intermediate care facility for the mentally retarded (ICF/MR) are not guaranteed a place for life. Neither are they guaranteed they won't have to move if their provider needs to "rearrange" clients. Separating residence from support gives an individual control over the most basic decisions…

Evaluation of Supported Placements in Integrated Community Environments Project (SPICE). Final Report.

ERIC Educational Resources Information Center

Wilson, Leslie; And Others

This evaluation project was designed to assess 37 persons (ages 21-72) who had moved from intermediate care facilities or skilled nursing facilities into innovative one-person or two-person community integrated living arrangements as a result of the Supported Placements in Integrated Community Environments project. The 37 persons had severe or…

Aposematism and crypsis are not enough to explain dorsal polymorphism in the Iberian adder

NASA Astrophysics Data System (ADS)

Martínez-Freiría, Fernando; Pérez i de Lanuza, Guillem; Pimenta, António A.; Pinto, Tiago; Santos, Xavier

2017-11-01

Aposematic organisms can show phenotypic variability across their distributional ranges. The ecological advantages of this variability have been scarcely studied in vipers. We explored this issue in Vipera seoanei, a species that exhibits five geographically structured dorsal colour phenotypes across Northern Iberia: two zigzag patterned (Classic and Cantabrica), one dorsal-strip patterned (Bilineata), one even grey (Uniform), and one melanistic (Melanistic). We compared predation rates (raptors and mammals) on plasticine models resembling each colour phenotype in three localities. Visual modelling techniques were used to infer detectability (i.e. conspicuousness) of each model type for visually guided predators (i.e. diurnal raptors). We hypothesize that predation rates will be lower for the two zigzag models (aposematism hypothesis) and that models with higher detectability would show higher predation rates (detectability hypothesis). Classic and Bilineata models were the most conspicuous, while Cantabrica and Uniform were the less. Melanistic presented an intermediate conspicuousness. Predation rate was low (3.24% of models) although there was variation in attack frequency among models. Zigzag models were scarcely predated supporting the aposematic role of the zigzag pattern in European vipers to reduce predation (aposematism hypothesis). From the non-zigzag models, high predation occurred on Bilineata and Melanistic models, and low on Uniform models, partially supporting our detectability hypothesis. These results suggest particular evolutionary advantages for non-zigzag phenotypes such as better performance of Melanistic phenotypes in cold environments or better crypsis of Uniform phenotypes. Polymorphism in V. seoanei may respond to a complex number of forces acting differentially across an environmental gradient.

SUPERMODEL ANALYSIS OF A1246 AND J255: ON THE EVOLUTION OF GALAXY CLUSTERS FROM HIGH TO LOW ENTROPY STATES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fusco-Femiano, R.; Lapi, A., E-mail: roberto.fuscofemiano@iaps.inaf.it

2015-02-10

We present an analysis of high-quality X-ray data out to the virial radius for the two galaxy clusters A1246 and GMBCG J255.34805+64.23661 (J255) by means of our entropy-based SuperModel. For A1246 we find that the spherically averaged entropy profile of the intracluster medium (ICM) progressively flattens outward, and that a nonthermal pressure component amounting to ≈20% of the total is required to support hydrostatic equilibrium in the outskirts; there we also estimate a modest value C ≈ 1.6 of the ICM clumping factor. These findings agree with previous analyses on other cool-core, relaxed clusters, and lend further support to themore » picture by Lapi et al. that relates the entropy flattening, the development of the nonthermal pressure component, and the azimuthal variation of ICM properties to weakening boundary shocks. In this scenario clusters are born in a high-entropy state throughout, and are expected to develop on similar timescales a low-entropy state both at the center due to cooling, and in the outskirts due to weakening shocks. However, the analysis of J255 testifies how such a typical evolutionary course can be interrupted or even reversed by merging especially at intermediate redshift, as predicted by Cavaliere et al. In fact, a merger has rejuvenated the ICM of this cluster at z ≈ 0.45 by reestablishing a high-entropy state in the outskirts, while leaving intact or erasing only partially the low-entropy, cool core at the center.« less

Maxillary implant-retained partial overdenture with Dolder bar attachment: a clinical report.

PubMed

Kim, Hyeongil; Buhite, Robert J; Monaco, Edward A

2015-03-01

This article describes a technique for maintaining a maxillary Kennedy III partial removable dental prosthesis design in a patient who had non-restorable failing abutments by replacing the abutments with dental implants. Two implants were placed immediately after extraction of the abutment teeth in the anterior maxilla. After the implants were fully integrated, a Dolder bar attachment was fitted onto the implants. A new maxillary partial removable dental prosthesis was fabricated using the implants and the remaining natural teeth as abutments to restore function and esthetics. With the aid of dental implants, this Kennedy III maxillary removable dental prosthesis design could provide additional retention and support by promoting cross-arch stability and tissue, implant and tooth support. The patient's satisfaction was significantly increased.

Composite resin root coping with a keeper for magnetic attachment for replacing the missing coronal portion of a removable partial denture abutment.

PubMed

Maeda, Yoshinobu; Nakao, Katsuhiko; Yagi, Kazutomo; Matsuda, Shisuke

2006-08-01

Numerous methods for replacing missing removable partial denture abutments have been introduced, however, most of them are time consuming and require several visits to complete the procedure. Since magnetic attachments can provide support and bracing as well as retention for overdenture abutments, the remaining tooth root structure can be used to support the coping with the keeper. Through the use of composite resin and adhesive material, improved retention of the keeper to the root may be achieved, along with improved esthetics. This article describes a method for replacing the missing abutment of a removable partial denture with a magnetic attachment, and a composite resin coping with a keeper.

High throughput operando studies using Fourier transform infrared imaging and Raman spectroscopy.

PubMed

Li, Guosheng; Hu, Dehong; Xia, Guanguang; White, J M; Zhang, Conrad

2008-07-01

A prototype high throughput operando (HTO) reactor designed and built for catalyst screening and characterization combines Fourier transform infrared (FT-IR) imaging and Raman spectroscopy in operando conditions. Using a focal plane array detector (HgCdTe focal plane array, 128x128 pixels, and 1610 Hz frame rate) for the FT-IR imaging system, the catalyst activity and selectivity of all parallel reaction channels can be simultaneously followed. Each image data set possesses 16 384 IR spectra with a spectral range of 800-4000 cm(-1) and with an 8 cm(-1) resolution. Depending on the signal-to-noise ratio, 2-20 s are needed to generate a full image of all reaction channels for a data set. Results on reactant conversion and product selectivity are obtained from FT-IR spectral analysis. Six novel Raman probes, one for each reaction channel, were specially designed and house built at Pacific Northwest National Laboratory, to simultaneously collect Raman spectra of the catalysts and possible reaction intermediates on the catalyst surface under operando conditions. As a model system, methanol partial oxidation reaction on silica-supported molybdenum oxide (MoO3SiO2) catalysts has been studied under different reaction conditions to demonstrate the performance of the HTO reactor.

Non-inductive Hybrid Scenario-Transport and Turbulence at Reduced Plasma Torque

NASA Astrophysics Data System (ADS)

Thome, K. E.; Petty, C. C.; Pace, D. C.; Turco, F.; Rhodes, T. L.

2016-10-01

As the neutral beam injection (NBI) torque is lowered in steady-state hybrid plasmas via counter-beam injection, increased turbulence and thermal transport is observed, particularly in the ion channel. These discharges require Pco-NBI = 11 MW and PECH = 3 MW to achieve zero surface loop voltage. As the beam torque is reduced from 8.5 N-m to 4 N-m with βN 3 and q95 6 , the global confinement decreases from H 98 y , 2 of 1.5 to 1.2 . Local transport analysis using TRANSP shows that the lower torque discharges have increased ion thermal diffusivity across the whole profile and increased electron thermal diffusivity localized to the ρ = 0.7 region. Similarly, Doppler Backscattering shows increased density fluctuations at intermediate wavenumbers at the lower torque. However, fast-ion transport caused by off-axis fishbones favorably decreases from 0.7m2 /s to 0.1m2 /s as the torque is lowered, partially offsetting the thermal transport reduction. These measured changes in turbulence and transport are being compared to plasma simulations using TGLF/GYRO to better predict the confinement of future steady-state hybrids that will be primarily RF-heated. Work supported by the US DOE under DE-FC02-04ER54698.

Dioxygenase-like reactivity of an isolable superoxo-nickel(II) complex.

PubMed

Company, Anna; Yao, Shenglai; Ray, Kallol; Driess, Matthias

2010-08-16

Although O(2) activation by metals such as iron and copper has been a matter of intensive research in the last decades, this type of chemistry for nickel systems is still in its infancy. Moreover, studies regarding the oxidizing ability of the resulting "Ni(n)-O(2)" species towards exogenous substrates are scarce. In this work, we report on the reactivity of an isolable and thermally stable mononuclear superoxo-nickel compound [Ni(II)(beta-diketiminato)(O(2))] (1) towards different types of organic substrates. In addition, we have been able to prove that the beta-diketiminato ligand can undergo partial intramolecular oxidation due to close proximity between the isopropyl groups of the beta-diketiminato-aryl and the superoxo subunits. Compound 1 performs hydrogen-atom abstraction from O-H and N-H groups and most importantly it shows an unprecedented dioxygenase-like reactivity in the oxidation of 2,4,6-tri-tert-butylphenol. The latter reaction most likely occurs through the mediation of a putative [Ni(III)-oxo] intermediate, affording an unprecedented oxidation product of the phenol that incorporates two oxygen atoms from a single O(2) subunit. Results presented herein provide evidence of the striking oxidizing ability of dioxygen-nickel species and further support the viability to use such systems as oxidation catalysts analogous to its heavy metal congener, palladium.

Structure and thermotropic phase behavior of sodium and potassium carboxylate ionomers

NASA Astrophysics Data System (ADS)

Mantsch, H. H.; Weng, S. F.; Yang, P. W.; Eysel, H. H.

1994-07-01

A molecular complex is formed between long-chain carboxylic acids and their alkali salts in a 1 : 1 mixture. These so-called "acid soaps" or carboxylate ionomers have multilamellar bilayer-type structures in solid state, which are retained in the presence of excess water, resembling the dispersions (gels) formed by typical two-chain amphiphiles, e.g. lipids. The special arrangement of hydrogen-bonded pairs of carboxylic acid and carboxylate groups into a unique "head-group" is supported by frequency shifts and partial or total disappearance of the characteristic vibrations of carboxylic acid dimers and of carboxylate groups. The existence of well-ordered hydrocarbon chains is demonstrated by the existence and polarization properties of the methylene rocking and wagging propagation modes. The gel to liquid-crystal phase transition of the hydrated acid soaps shows practically no cation dependence, unlike the corresponding phase transition in neutral soaps which varies considerably with the nature of the counterion. There is spectroscopic evidence to suggest a cooperative process that involves "melting" of the alkyl chains and disintegration of the hydrogen-bonded carboxylate—carboxylic acid complex, followed by a cation-dependent equilibrium that favors the formation of acid dimers at elevated temperatures and some form of hydrogen-bonded ion pair aggregates at intermediate temperatures.

Astrocytes influence the severity of spinal muscular atrophy

PubMed Central

Rindt, Hansjörg; Feng, Zhihua; Mazzasette, Chiara; Glascock, Jacqueline J.; Valdivia, David; Pyles, Noah; Crawford, Thomas O.; Swoboda, Kathryn J.; Patitucci, Teresa N.; Ebert, Allison D.; Sumner, Charlotte J.; Ko, Chien-Ping; Lorson, Christian L.

2015-01-01

Systemically low levels of survival motor neuron-1 (SMN1) protein cause spinal muscular atrophy (SMA). α-Motor neurons of the spinal cord are considered particularly vulnerable in this genetic disorder and their dysfunction and loss cause progressive muscle weakness, paralysis and eventually premature death of afflicted individuals. Historically, SMA was therefore considered a motor neuron-autonomous disease. However, depletion of SMN in motor neurons of normal mice elicited only a very mild phenotype. Conversely, restoration of SMN to motor neurons in an SMA mouse model had only modest effects on the SMA phenotype and survival. Collectively, these results suggested that additional cell types contribute to the pathogenesis of SMA, and understanding the non-autonomous requirements is crucial for developing effective therapies. Astrocytes are critical for regulating synapse formation and function as well as metabolic support for neurons. We hypothesized that astrocyte functions are disrupted in SMA, exacerbating disease progression. Using viral-based restoration of SMN specifically to astrocytes, survival in severe and intermediate SMA mice was observed. In addition, neuromuscular circuitry was improved. Astrogliosis was prominent in end-stage SMA mice and in post-mortem patient spinal cords. Increased expression of proinflammatory cytokines was partially normalized in treated mice, suggesting that astrocytes contribute to the pathogenesis of SMA. PMID:25911676

Erythrocyte phosphofructokinase in rat strains with genetically determined differences in 2,3-diphosphoglycerate levels.

PubMed

Noble, N A; Tanaka, K R

1981-02-01

We have studied the erythrocyte enzyme phosphofructokinase (PFK) from two strains of Long-Evans rats with genetically determined differences in erythrocyte 2,3-diphosphoglycerate (DPG) levels. The DPG difference is due to two alleles at one locus. With one probable exception, the genotype at this locus is always associated with the hemoglobin (Hb) electrophoretic phenotype, due to a polymorphism at the III beta-globin locus. The enzyme PFK has been implicated in the DPG difference because glycolytic intermediate levels suggest that this enzyme has a higher in vivo activity in High-DPG strain rats, although the total PFK activity does not differ. We report here that partially purified erythrocyte PFK from Low-DPG strain cells is inhibited significantly more at physiological levels of DPG (P less than 0.01) than PFK from High-DPG strain erythrocytes. Citrate and adenosine triphosphate also inhibit the Low-DPG enzyme more than the High-DPG enzyme. Therefore, a structurally different PFK, with a greater sensitivity to inhibitors, may explain the lower DPG and ATP levels observed in Low-DPG strain animals. These data support a two-locus (Hb and PFK) hypothesis and provide a gene marker to study the underlying genetic and physiologic relationships of these loci.

Structural analysis of viral replicative intermediates isolated from adenovirus type 2-infected HeLa cell nuclei.

PubMed Central

Kedinger, C; Brison, O; Perrin, F; Wilhelm, J

1978-01-01

Deoxyribonucleoprotein complexes released 17 h postinfection from adenovirus type 1 (Ad2)-infected HeLa cell nuclei were shown by electron microscopy to contain filaments much thicker (about 200 A [20 nm]) than double-stranded DNA (about 20 A [2 nm]). The complexes were partially purified through a linear sucrose gradient, concentrated, and further purified in a metrizamide gradient. The major protein present in the complexes was identified as the 72,000-dalton (72K), adenovirus-coded single-stranded DNA-binding protein (72K DBP). Three types of complexes have been visualized by electron microscopy. Some linear complexes were uniformly thick, and their length corresponded roughly to that of the adenovirus genome. Other linear genome-length complexes appeared to consist of a thick filament connected to a thinner filament with the diameter of double-stranded DNA. Forked complexes consisting of one thick filament connected to a genome-length, thinner double-stranded DNA filament were also visualized. Both thick and thin filaments were sensitive to DNase and not to RNase, but only the thick filaments were digested by the single-strand-specific Neurospora crassa nuclease, indicating that they correspond to a complex of 72K DBP and Ad2 single-stranded DNA. Experiments with anti-72K DBP immunoglobulins indicated that these nucleoprotein complexes, containing the 72K DBP, correspond to replicative intermediates. Both strands of the Ad2 genome were found associated to the 72K DBP. Altogether, our results establish the in vivo association of the 72K DBP with adenovirus single-stranded DNA, as previously suggested from in vitro studies, and support a strand displacement mechanism for Ad2 DNA replication, in which both strands can be displaced. In addition, our results indicate that, late in infection, histones are not bound to adenovirus DNA in the form of a nucleosomal chromatine-like structure. Images PMID:207893

Structural analysis of viral replicative intermediates isolated from adenovirus type 2-infected HeLa cell nuclei.

PubMed

Kedinger, C; Brison, O; Perrin, F; Wilhelm, J

1978-05-01

Deoxyribonucleoprotein complexes released 17 h postinfection from adenovirus type 1 (Ad2)-infected HeLa cell nuclei were shown by electron microscopy to contain filaments much thicker (about 200 A [20 nm]) than double-stranded DNA (about 20 A [2 nm]). The complexes were partially purified through a linear sucrose gradient, concentrated, and further purified in a metrizamide gradient. The major protein present in the complexes was identified as the 72,000-dalton (72K), adenovirus-coded single-stranded DNA-binding protein (72K DBP). Three types of complexes have been visualized by electron microscopy. Some linear complexes were uniformly thick, and their length corresponded roughly to that of the adenovirus genome. Other linear genome-length complexes appeared to consist of a thick filament connected to a thinner filament with the diameter of double-stranded DNA. Forked complexes consisting of one thick filament connected to a genome-length, thinner double-stranded DNA filament were also visualized. Both thick and thin filaments were sensitive to DNase and not to RNase, but only the thick filaments were digested by the single-strand-specific Neurospora crassa nuclease, indicating that they correspond to a complex of 72K DBP and Ad2 single-stranded DNA. Experiments with anti-72K DBP immunoglobulins indicated that these nucleoprotein complexes, containing the 72K DBP, correspond to replicative intermediates. Both strands of the Ad2 genome were found associated to the 72K DBP. Altogether, our results establish the in vivo association of the 72K DBP with adenovirus single-stranded DNA, as previously suggested from in vitro studies, and support a strand displacement mechanism for Ad2 DNA replication, in which both strands can be displaced. In addition, our results indicate that, late in infection, histones are not bound to adenovirus DNA in the form of a nucleosomal chromatine-like structure.

Phylogenetic relationship of the Brazilian isolates of the rat lungworm Angiostrongylus cantonensis (Nematoda: Metastrongylidae) employing mitochondrial COI gene sequence data

PubMed Central

2012-01-01

Background The rat lungworm Angiostrongylus cantonensis can cause eosinophilic meningoencephalitis in humans. This nematode’s main definitive hosts are rodents and its intermediate hosts are snails. This parasite was first described in China and currently is dispersed across several Pacific islands, Asia, Australia, Africa, some Caribbean islands and most recently in the Americas. Here, we report the genetic variability among A. cantonensis isolates from different geographical locations in Brazil using mitochondrial cytochrome c oxidase subunit I (COI) gene sequences. Methods The isolates of A. cantonensis were obtained from distinct geographical locations of Brazil. Genomic DNAs were extracted, amplified by polymerase reaction, purified and sequenced. A partial sequence of COI gene was determined to assess their phylogenetic relationship. Results The sequences of A. cantonensis were monophyletic. We identified a distinct clade that included all isolates of A. cantonensis from Brazil and Asia based on eight distinct haplotypes (ac1, ac2, ac3, ac4, ac5, ac6, ac7 and ac8) from a previous study. Interestingly, the Brazilian haplotype ac5 is clustered with isolates from Japan, and the Brazilian haplotype ac8 from Rio de Janeiro, São Paulo, Pará and Pernambuco states formed a distinct clade. There is a divergent Brazilian haplotype, which we named ac9, closely related to Chinese haplotype ac6 and Japanese haplotype ac7. Conclusion The genetic variation observed among Brazilian isolates supports the hypothesis that the appearance of A. cantonensis in Brazil is likely a result of multiple introductions of parasite-carrying rats, transported on ships due to active commerce with Africa and Asia during the European colonization period. The rapid spread of the intermediate host, Achatina fulica, also seems to have contributed to the dispersion of this parasite and the infection of the definitive host in different Brazilian regions. PMID:23130987

The timing of compositionally-zoned magma reservoirs and mafic 'priming' weeks before the 1912 Novarupta-Katmai rhyolite eruption

USGS Publications Warehouse

Singer, Brad S.; Costa, Fidel; Herrin, Jason S.; Hildreth, Wes; Fierstein, Judith

2016-01-01

The June 6, 1912 eruption of more than 13 km3 of dense rock equivalent (DRE) magma at Novarupta vent, Alaska was the largest of the 20th century. It ejected >7 km3 of rhyolite, ~1.3 km3 of andesite and ~4.6 km3 of dacite. Early ideas about the origin of pyroclastic flows and magmatic differentiation (e.g., compositional zonation of reservoirs) were shaped by this eruption. Despite being well studied, the timing of events that led to the chemically and mineralogically zoned magma reservoir remain poorly known. Here we provide new insights using the textures and chemical compositions of plagioclase and orthopyroxene crystals and by reevaluating previous U-Th isotope data. Compositional zoning of the magma reservoir likely developed a few thousand years before the eruption by several additions of mafic magma below an extant silicic reservoir. Melt compositions calculated from Sr contents in plagioclase fill the compositional gap between 68 and 76% SiO2 in whole pumice clasts, consistent with uninterrupted crystal growth from a continuum of liquids. Thus, our findings support a general model in which large volumes of crystal-poor rhyolite are related to intermediate magmas through gradual separation of melt from crystal-rich mush. The rhyolite is incubated by, but not mixed with, episodic recharge pulses of mafic magma that interact thermochemically with the mush and intermediate magmas. Hot, Mg-, Ca-, and Al-rich mafic magma intruded into, and mixed with, deeper parts of the reservoir (andesite and dacite) multiple times. Modeling the relaxation of the Fe-Mg concentrations in orthopyroxene and Mg in plagioclase rims indicates that the final recharge event occurred just weeks prior to the eruption. Rapid addition of mass, volatiles, and heat from the recharge magma, perhaps aided by partial melting of cumulate mush below the andesite and dacite, pressurized the reservoir and likely propelled a ~10 km lateral dike that allowed the overlying rhyolite to reach the surface.

Relationship between day 1 and day 2 Vancomycin area under the curve values and emergence of heterogeneous Vancomycin-intermediate Staphylococcus aureus (hVISA) by Etest® macromethod among patients with MRSA bloodstream infections: a pilot study.

PubMed

Martirosov, Dmitriy M; Bidell, Monique R; Pai, Manjunath P; Scheetz, Marc H; Rosenkranz, Susan L; Faragon, Corey; Malik, M; Mendes, R E; Jones, R N; McNutt, Louise-Anne; Lodise, Thomas P

2017-08-02

In vitro data suggests that suboptimal initial vancomycin exposure may select for heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) infections. However, no clinical studies have evaluated the relationship between initial vancomycin exposure and emergence of hVISA. This pilot study seeks to assess the relationship between day 1 and day 2 vancomycin area under the curve (AUC) and emergence of hVISA bloodstream infections (BSIs) by Etest® macromethod among patients with a non-hVISA BSI at baseline. This was a retrospective cohort study of patients with methicillin-resistant Staphylococcus aureus (MRSA) BSIs at Albany Medical Center Hospital (AMCH) between January 2005 and June 2009. The vancomycin AUC exposure variables on day 1 (AUC 0-24h ) and day 2 (AUC 24-48h ) were estimated using the maximal a posteriori probability (MAP) procedure in ADAPT 5. There were 238 unique episodes of MRSA BSIs during the study period, 119 of which met inclusion criteria. Overall, hVISA emerged in 7/119 (5.9%) of patients. All 7 cases of hVISA involved patients who did not achieve area under the curve over broth microdilution minimum inhibitory concentration (AUC 0-24h /MIC BMD ) ratio of 521 or an AUC 24-48h /MIC BMD ratio of 650. No associations between other day 1 and day 2 AUC variables and emergence of hVISA were noted. Although more data are needed to draw definitive conclusions, these findings suggest that hVISA emergence among patients with non-hVISA MRSA BSIs at baseline may be partially explained by suboptimal exposure to vancomycin in the first 1 to 2 days of therapy. At a minimum, these findings support further study of the relationship between initial vancomycin exposure and hVISA emergence among patients with MRSA BSIs in a well-powered, multi-center, prospective trial.

Inspection apparatus for evaluating a partially completed weld

DOEpatents

Smartt, Herschel B.; Larsen, Eric D.; Johnson, Jonn A.

2001-01-01

An inspection apparatus for evaluating a partially completed weld is described and which is utilized in combination with an automated movable welder which moves across a supporting surface, and wherein the inspection apparatus includes a coupling member mounted on the welder; a frame member mounted on the coupling member; an ultrasonic sensor mounted on the frame member and disposed in ultrasonic sound transmitting relation relative to the partially completed weld; and a drive assembly for adjusting the position of the ultrasonic sensor relative to the partially completed weld.

Point Mutations in the Stem Region and the Fourth AAA Domain of Cytoplasmic Dynein Heavy Chain Partially Suppress the Phenotype of NUDF/LIS1 Loss in Aspergillus nidulans

PubMed Central

Zhuang, Lei; Zhang, Jun; Xiang, Xin

2007-01-01

Cytoplasmic dynein performs multiple cellular tasks but its regulation remains unclear. The dynein heavy chain has a N-terminal stem that binds to other subunits and a C-terminal motor unit that contains six AAA (ATPase associated with cellular activities) domains and a microtubule-binding site located between AAA4 and AAA5. In Aspergillus nidulans, NUDF (a LIS1 homolog) functions in the dynein pathway, and two nudF6 partial suppressors were mapped to the nudA dynein heavy chain locus. Here we identified these two mutations. The nudAL1098F mutation resides in the stem region, and nudAR3086C is in the end of AAA4. These mutations partially suppress the phenotype of nudF deletion but do not suppress the phenotype exhibited by mutants of dynein intermediate chain and Arp1. Surprisingly, the stronger ΔnudF suppressor, nudAR3086C, causes an obvious decrease in the basal level of dynein's ATPase activity and an increase in dynein's distribution along microtubules. Thus, suppression of the ΔnudF phenotype may result from mechanisms other than simply the enhancement of dynein's ATPase activity. The fact that a mutation in the end of AAA4 negatively regulates dynein's ATPase activity but partially compensates for NUDF loss indicates the importance of the AAA4 domain in dynein regulation in vivo. PMID:17237507

Flow field and scalar measurements in a series of turbulent partially-premixed dimethyl ether/air jet flames

DOE PAGES

Coriton, Bruno; Im, Seong -Kyun; Gamba, Mirko; ...

2017-03-12

Here, we present a series of benchmark flames consisting of six partially-premixed piloted dimethyl ether (DME)/air jet flames. These flames provide an opportunity to understand turbulence-flame interactions for oxygenated fuels and to develop predictive models for these interactions using a canonical burner geometry. The development of accurate models for DME/air flames would establish a foundation for studies of more complex oxygenated fuels. The flames are stabilized on a piloted jet burner similar to that of the partially-premixed methane/air jet flames that have been studied extensively within the context of the TNF Workshop. This series of six jet flames spans jetmore » exit Reynolds numbers, ReD, from 29,300 to 73,300 and stoichiometric mixture fractions, ξ st, from 0.35 to 0.60. Flame conditions range from very low probability of localized extinction to a high probability of localized extinction and subsequent re-ignition. Measurements in the flames are compared at downstream locations from 5 to 25 diameters above the nozzle exit. Mean and fluctuating velocity components are measured using stereo particle image velocimetry (SPIV). Simultaneous laser-induced fluorescence (LIF) imaging of OH and CH 2O provides insights into the distribution of these intermediate species in partially-premixed DME/air flames. OH LIF imaging is also combined with SPIV to investigate the strain rate field across the reaction zone.« less

On the aquitard-aquifer interface flow and the drawdown sensitivity with a partially penetrating pumping well in an anisotropic leaky confined aquifer

NASA Astrophysics Data System (ADS)

Feng, Qinggao; Zhan, Hongbin

2015-02-01

A mathematical model for describing groundwater flow to a partially penetrating pumping well of a finite diameter in an anisotropic leaky confined aquifer is developed. The model accounts for the jointed effects of aquitard storage, aquifer anisotropy, and wellbore storage by treating the aquitard leakage as a boundary condition at the aquitard-aquifer interface rather than a volumetric source/sink term in the governing equation, which has never developed before. A new semi-analytical solution for the model is obtained by the Laplace transform in conjunction with separation of variables. Specific attention was paid on the flow across the aquitard-aquifer interface, which is of concern if aquitard and aquifer have different pore water chemistry. Moreover, Laplace-domain and steady-state solutions are obtained to calculate the rate and volume of (total) leakage through the aquitard-aquifer interface due to pump in a partially penetrating well, which is also useful for engineers to manager water resources. The sensitivity analyses for the drawdown illustrate that the drawdown is most sensitive to the well partial penetration. It is apparently sensitive to the aquifer anisotropic ratio over the entire time of pumping. It is moderately sensitive to the aquitard/aquifer specific storage ratio at the intermediate times only. It is moderately sensitive to the aquitard/aquifer vertical hydraulic conductivity ratio and the aquitard/aquifer thickness ratio with the identical influence at late times.

Flow field and scalar measurements in a series of turbulent partially-premixed dimethyl ether/air jet flames

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coriton, Bruno; Im, Seong -Kyun; Gamba, Mirko

Here, we present a series of benchmark flames consisting of six partially-premixed piloted dimethyl ether (DME)/air jet flames. These flames provide an opportunity to understand turbulence-flame interactions for oxygenated fuels and to develop predictive models for these interactions using a canonical burner geometry. The development of accurate models for DME/air flames would establish a foundation for studies of more complex oxygenated fuels. The flames are stabilized on a piloted jet burner similar to that of the partially-premixed methane/air jet flames that have been studied extensively within the context of the TNF Workshop. This series of six jet flames spans jetmore » exit Reynolds numbers, ReD, from 29,300 to 73,300 and stoichiometric mixture fractions, ξ st, from 0.35 to 0.60. Flame conditions range from very low probability of localized extinction to a high probability of localized extinction and subsequent re-ignition. Measurements in the flames are compared at downstream locations from 5 to 25 diameters above the nozzle exit. Mean and fluctuating velocity components are measured using stereo particle image velocimetry (SPIV). Simultaneous laser-induced fluorescence (LIF) imaging of OH and CH 2O provides insights into the distribution of these intermediate species in partially-premixed DME/air flames. OH LIF imaging is also combined with SPIV to investigate the strain rate field across the reaction zone.« less

Implant-supported and magnet-retained oral-nasal combination prosthesis in a patient with a total rhinectomy and partial maxillectomy due to cancer: A clinical report.

PubMed

Won, Alexander M; Montgomery, Patti; Aponte-Wesson, Ruth; Chambers, Mark

2017-02-01

This clinical report describes the fabrication of an implant-supported and magnet-retained combination oral-nasal prosthesis for a patient with a midline midfacial defect. The patient had undergone a total rhinectomy and partial maxillectomy as part of his cancer treatment. The nasal prosthesis was retained on the face by a magnet attached to the implant-supported maxillary denture, resulting in improved appearance and the recovery of speech, mastication, and swallowing functions. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

'Laminopathies': A wide spectrum of human diseases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Worman, Howard J.; Bonne, Gisele; Universite Pierre et Marie Curie-Paris 6, Faculte de medecine, Paris F-75013

2007-06-10

Mutations in genes encoding the intermediate filament nuclear lamins and associated proteins cause a wide spectrum of diseases sometimes called 'laminopathies.' Diseases caused by mutations in LMNA encoding A-type lamins include autosomal dominant Emery-Dreifuss muscular dystrophy and related myopathies, Dunnigan-type familial partial lipodystrophy, Charcot-Marie-Tooth disease type 2B1 and developmental and accelerated aging disorders. Duplication in LMNB1 encoding lamin B1 causes autosomal dominant leukodystrophy and mutations in LMNB2 encoding lamin B2 are associated with acquired partial lipodystrophy. Disorders caused by mutations in genes encoding lamin-associated integral inner nuclear membrane proteins include X-linked Emery-Dreifuss muscular dystrophy, sclerosing bone dysplasias, HEM/Greenberg skeletal dysplasiamore » and Pelger-Huet anomaly. While mutations and clinical phenotypes of 'laminopathies' have been carefully described, data explaining pathogenic mechanisms are only emerging. Future investigations will likely identify new 'laminopathies' and a combination of basic and clinical research will lead to a better understanding of pathophysiology and the development of therapies.« less

Accessory oral cavity associated with duplication of the tongue and the mandible in a newborn: a rare case of Diprosopus. Multi-row detector computed tomography diagnostic role.

PubMed

Morabito, Rosa; Colonna, Michele R; Mormina, Enricomaria; Stagno d'Alcontres, Ferdinando; Salpietro, Vincenzo; Blandino, Alfredo; Longo, Marcello; Granata, Francesca

2014-12-01

Craniofacial duplication is a very rare malformation. The phenotype comprises a wide spectrum, ranging from partial duplication of few facial structures to complete dicephalus. We report the case of a newborn with an accessory oral cavity associated to duplication of the tongue and the mandible diagnosed by multi-row detector Computed Tomography, few days after her birth. Our case of partial craniofacial duplication can be considered as Type II of Gorlin classification or as an intermediate form between Type I and Type II of Sun classification. Our experience demonstrates that CT scan, using appropriate reconstruction algorithms, permits a detailed evaluation of the different structures in an anatomical region. Multi-row CT scan is also the more accurate diagnostic procedure for the pre-surgical evaluation of craniofacial malformations. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Tuning and Freezing Disorder in Photonic Crystals using Percolation Lithography

PubMed Central

Burgess, Ian B.; Abedzadeh, Navid; Kay, Theresa M.; Shneidman, Anna V.; Cranshaw, Derek J.; Lončar, Marko; Aizenberg, Joanna

2016-01-01

Although common in biological systems, synthetic self-assembly routes to complex 3D photonic structures with tailored degrees of disorder remain elusive. Here we show how liquids can be used to finely control disorder in porous 3D photonic crystals, leading to complex and hierarchical geometries. In these optofluidic crystals, dynamically tunable disorder is superimposed onto the periodic optical structure through partial wetting or evaporation. In both cases, macroscopic symmetry breaking is driven by subtle sub-wavelength variations in the pore geometry. These variations direct site-selective infiltration of liquids through capillary interactions. Incorporating cross-linkable resins into our liquids, we developed methods to freeze in place the filling patterns at arbitrary degrees of partial wetting and intermediate stages of drying. These percolation lithography techniques produced permanent photonic structures with adjustable disorder. By coupling strong changes in optical properties to subtle differences in fluid behavior, optofluidic crystals may also prove useful in rapid analysis of liquids. PMID:26790372

Random sampling of constrained phylogenies: conducting phylogenetic analyses when the phylogeny is partially known.

PubMed

Housworth, E A; Martins, E P

2001-01-01

Statistical randomization tests in evolutionary biology often require a set of random, computer-generated trees. For example, earlier studies have shown how large numbers of computer-generated trees can be used to conduct phylogenetic comparative analyses even when the phylogeny is uncertain or unknown. These methods were limited, however, in that (in the absence of molecular sequence or other data) they allowed users to assume that no phylogenetic information was available or that all possible trees were known. Intermediate situations where only a taxonomy or other limited phylogenetic information (e.g., polytomies) are available are technically more difficult. The current study describes a procedure for generating random samples of phylogenies while incorporating limited phylogenetic information (e.g., four taxa belong together in a subclade). The procedure can be used to conduct comparative analyses when the phylogeny is only partially resolved or can be used in other randomization tests in which large numbers of possible phylogenies are needed.

The structure of partially-premixed methane/air flames under varying premixing

NASA Astrophysics Data System (ADS)

Kluzek, Celine; Karpetis, Adonios

2008-11-01

The present work examines the spatial and scalar structure of laminar, partially premixed methane/air flames with the objective of developing flamelet mappings that capture the effect of varying premixture strength (air addition in fuel.) Experimental databases containing full thermochemistry measurements within laminar axisymmetric flames were obtained at Sandia National Laboratories, and the measurements of all major species and temperature are compared to opposed-jet one-dimensional flow simulation using Cantera and the full chemical kinetic mechanism of GRI 3.0. Particular emphasis is placed on the scalar structure of the laminar flames, and the formation of flamelet mappings that capture all of the salient features of thermochemistry in a conserved scalar representation. Three different premixture strengths were examined in detail: equivalence ratios of 1.8, 2.2, and 3.17 resulted in clear differences in the flame scalar structure, particularly in the position of the rich premixed flame zone and the attendant levels of major and intermediate species (carbon monoxide and hydrogen).

The evolution of the moon and the terrestrial planets

NASA Technical Reports Server (NTRS)

Toksoez, M. N.; Johnston, D. H.

1974-01-01

The thermal evolutions of the Moon, Mars, Venus and Mercury are calculated theoretically starting from cosmochemical condensation models. An assortment of geological, geochemical and geophysical data are used to constrain both the present day temperatures and the thermal histories of the planets' interiors. Such data imply that the planets were heated during or shortly after formation and that all the terrestrial planets started their differentiations early in their history. The moon, smallest in size, is characterized as a differentiated body with a crust, a thick solid mantle and an interior region which may be partially molten. Mars, intermediate in size, is assumed to have differentiated an Fe-FeS core. Venus is characterized as a planet not unlike the earth in many respects. Core formation has occurred probably during the first billion years after the formation. Mercury, which probably has a large core, may have a 500 km thick solid lithosphere and a partially molten core if it is assumed that some heat sources exist in the core.

Failure Characteristics of Granite Influenced by Sample Height-to-Width Ratios and Intermediate Principal Stress Under True-Triaxial Unloading Conditions

NASA Astrophysics Data System (ADS)

Li, Xibing; Feng, Fan; Li, Diyuan; Du, Kun; Ranjith, P. G.; Rostami, Jamal

2018-05-01

The failure modes and peak unloading strength of a typical hard rock, Miluo granite, with particular attention to the sample height-to-width ratio (between 2 and 0.5), and the intermediate principal stress was investigated using a true-triaxial test system. The experimental results indicate that both sample height-to-width ratios and intermediate principal stress have an impact on the failure modes, peak strength and severity of rockburst in hard rock under true-triaxial unloading conditions. For longer rectangular specimens, the transition of failure mode from shear to slabbing requires higher intermediate principal stress. With the decrease in sample height-to-width ratios, slabbing failure is more likely to occur under the condition of lower intermediate principal stress. For same intermediate principal stress, the peak unloading strength monotonically increases with the decrease in sample height-to-width. However, the peak unloading strength as functions of intermediate principal stress for different types of rock samples (with sample height-to-width ratio of 2, 1 and 0.5) all present the pattern of initial increase, followed by a subsequent decrease. The curves fitted to octahedral shear stress as a function of mean effective stress also validate the applicability of the Mogi-Coulomb failure criterion for all considered rock sizes under true-triaxial unloading conditions, and the corresponding cohesion C and internal friction angle φ are calculated. The severity of strainburst of granite depends on the sample height-to-width ratios and intermediate principal stress. Therefore, different supporting strategies are recommended in deep tunneling projects and mining activities. Moreover, the comparison of test results of different σ 2/ σ 3 also reveals the little influence of minimum principal stress on failure characteristics of granite during the true-triaxial unloading process.

Partial melting of amphibolites in the Eastern Segment of the Sveconorwegian orogen, southern Sweden.

NASA Astrophysics Data System (ADS)

Brophy, E.; Hansen, E. C.; Möller, C.; Huffman, M.

2017-12-01

Mafic migmatites with amphibolitic melanosome and tonalitic leucosome are a common feature in continental collision orogenic zones. However, the anatexis of mafic rocks has received much less attention than anatexis in felsic, intermediate or pelitic compositions. We examined mafic migmatites along a traverse within the Eastern Segment of the 1.14-0.9 Ga Sveconorwegian orogen, between Forsheda and Fegen southern Sweden. This traverse occurs in the center of a >150 km metamorphic transition from sub-greenschist facies in the east to high-pressure granulite and eclogite facies in the west (Möller and Andersson, unpublished metamorphic map). The Eastern Segment is a parautochthonous belt made up of rocks of the Fennoscandian shield that were deformed and metamorphosed during the Sveconorwegian orogeny. Within the traverse amphibolite bodies occur within migmatitic felsic to intermediate orthogneisses. The first appearance of tonalitic leucosome in amphibolite was observed towards the eastern edge of the traverse and continued to occur sporadically westward ranging in abundance (by outcrop area) from 0 to 25 %. The mineral assemblage in amphibolite is hbl + plag ( An30) + qtz + bt ± grt ± ilm ± ttn ± py ± SO2-rich scp. No examples of peritectic pyroxene associated with leucosome were found. The lack of peritectic pyroxene suggests that a water-rich phase was present at the onset of anatexis. The highly variable amount of leucosome further suggests that the amount of melt generated was determined by the amount of water available. Together these suggest that partial was driven by the local influx of a water-rich fluid. In the higher grade portions further west migmatitic amphibolite with tonalitic leucosome occurs in two varieties: one with peritectic pyroxene and relatively small amounts of leucosome, interpreted as forming by water-undersaturated dehydration melting, and another without peritectic pyroxene and with larger amounts of leucosome which is interpreted as having formed from water-fluxed melting (Hansen et al., Lithos, 2015). Thus, water-undersaturated melting in mafic rocks appears to have been limited to the higher-grade portions of the orogen. The variable amounts of leucosome produced by partial melting indicate that the presence of water-rich fluids was localized rather than penetrative.

A multispectral view of the periodic events in η Carinae†‡§¶

NASA Astrophysics Data System (ADS)

Damineli, A.; Hillier, D. J.; Corcoran, M. F.; Stahl, O.; Groh, J. H.; Arias, J.; Teodoro, M.; Morrell, N.; Gamen, R.; Gonzalez, F.; Leister, N. V.; Levato, H.; Levenhagen, R. S.; Grosso, M.; Colombo, J. F. Albacete; Wallerstein, G.

2008-06-01

A full description of the 5.5-yr low excitation events in η Carinae is presented. We show that they are not as simple and brief as previously thought, but a combination of two components. The first, the slow variation component, is revealed by slow changes in the ionization level of circumstellar matter across the whole cycle and is caused by gradual changes in the wind-wind collision shock-cone orientation, angular opening and gaseous content. The second, the collapse component, is restricted to around the minimum, and is due to a temporary global collapse of the wind-wind collision shock. High-energy photons (E > 16 eV) from the companion star are strongly shielded, leaving the Weigelt objects at low-ionization state for more than six months. High-energy phenomena are sensitive only to the collapse, low energy only to the slow variation and intermediate energies to both components. Simple eclipses and mechanisms effective only near periastron (e.g. shell ejection or accretion on to the secondary star) cannot account for the whole 5.5-yr cycle. We find anti-correlated changes in the intensity and the radial velocity of P Cygni absorption profiles in FeII λ6455 and HeI λ7065 lines, indicating that the former is associated to the primary and the latter to the secondary star. We present a set of light curves representative of the whole spectrum, useful for monitoring the next event (2009 January 11). Based partially on data collected at the OPD-LNA/MCT. Based partially on data collected at ESO telescopes. ‡ Based partially on data collected at Casleo Observatory. § Based partially on data collected at Magellan Telescopes. ¶ Based partially on data collected at CTIO. ∥ E-mail: damineli@astro.iag.usp.br

Technical brief: Pump-probe paradigm in an integrating cavity to study photodecomposition processes

PubMed Central

Betts-Obregon, Brandi; Tsin, Andrew T.; DeSa, Richard J.

2016-01-01

Purpose Assaying photodecomposition is challenging because light must be used to initiate the photodamage and light must be used to monitor the photodecomposition. The experimental requirements are as follows: 1) During exposure of the actinic beam, continuously monitor the spectral characteristics of the sample, 2) uniformly expose the reactants to the actinic source, 3) obtain informative spectra in the presence of light scatter, and 4) achieve sufficient sensitivity for dilute reactants. Traditional spectrophotometers cannot address these issues due to sample turbidity, the inability to uniformly expose the cuvette contents to the incident beam, the inability to simultaneously perform spectral scans, and inherent low sensitivity. Here, we describe a system that meets these challenges in a practical way. Methods Light access to a 8.6 ml quartz integrating sphere containing 10 µM all-trans retinol in PBS was provided by three ports at right angles allowing for the following: 1) actinic light delivery from light-emitting diodes (LEDs) firing at 100 pulses/sec, 2) entry of a separate scanning beam at 100 scans/sec (10,000 µsec scan time) via an OLIS RSM 1000 ultraviolet/visual (UV/Vis) rapid-scanning spectrophotometer (RSM), and 3) light exit to the detector photomultiplier. The RSM spectral intermediate slit was partially covered to allow for a “dark” period of 2,000 µsec when no scanning light was admitted to the cuvette. During that interval, the LED was flashed, and the photomultiplier was temporarily blocked by a perforated spinning shutter disk. The absorbance per centimeter, which is increased due to the internal reflectance of the integrating sphere compared to a standard 1 cm rectangular cuvette, was calculated according to Fry et al. (2010) Applied Optics 49:575. Retinoid photodecomposition was confirmed with high-performance liquid chromatography (HPLC). Results Using the RSM to trigger the LED flash and photomultiplier shutter closure during the “dark” period allowed actinic flashes to be placed between scans. Exposure of the all-trans retinol to 366 nm flashes resulted in marked reduction in absorbance and a blue shift of the λmax. A white LED, despite its higher photon output, did not support all-trans retinol photolysis. Singular value decomposition (SVD) analysis revealed three spectral intermediates with mechanism, I -> II -> III. HPLC analysis of the reactants at the beginning and the conclusion of the light exposure confirmed the retinol photodecomposition. Conclusions The highly reflecting cavity acts as a multipass cuvette that markedly increased the light path length and, thus, sensitivity. Triggering the LED during a dark period within the scan time allowed the actinic flashes to be interleafed between scans in a pump-probe paradigm. Furthermore, the entire sample was exposed to scan beam and actinic flashes, which is not possible in traditional spectrophotometers. Finally, the integrating cavity cuvette allowed use of turbid samples. SVD was useful for resolving spectral intermediates. Although the identity of the intermediates was not determined here, the ability to define molecular intermediates during photodecomposition reactions will allow future studies to isolate and identify the degradation products and determine the mechanism of light-induced retinoid degradation and that of retinoid-binding protein-mediated photoprotection. PMID:27559291

Post-traumatic stress symptoms in Swedish obstetricians and midwives after severe obstetric events: a cross-sectional retrospective survey.

PubMed

Wahlberg, Å; Andreen Sachs, M; Johannesson, K; Hallberg, G; Jonsson, M; Skoog Svanberg, A; Högberg, U

2017-07-01

To examine post-traumatic stress reactions among obstetricians and midwives, experiences of support and professional consequences after severe events in the labour ward. Cross-sectional online survey from January 7 to March 10, 2014. Members of the Swedish Society of Obstetrics and Gynaecology and the Swedish Association of Midwives. Potentially traumatic events were defined as: the child died or was severely injured during delivery; maternal near-miss; maternal mortality; and other events such as violence or threat. The validated Screen Questionnaire Posttraumatic Stress Disorder (SQ-PTSD), based on DSM-IV (1994) 4th edition, was used to assess partial post-traumatic stress disorder (PTSD) and probable PTSD. Partial or probable PTSD. The response rate was 47% for obstetricians (n = 706) and 40% (n = 1459) for midwives. Eighty-four percent of the obstetricians and 71% of the midwives reported experiencing at least one severe event on the delivery ward. Fifteen percent of both professions reported symptoms indicative of partial PTSD, whereas 7% of the obstetricians and 5% of the midwives indicated symptoms fulfilling PTSD criteria. Having experienced emotions of guilt or perceived insufficient support from friends predicted a higher risk of suffering from partial or probable PTSD. Obstetricians and midwives with partial PTSD symptoms chose to change their work to outpatient care significantly more often than colleagues without these symptoms. A substantial proportion of obstetricians and midwives reported symptoms of partial or probable PTSD after severe traumatic events experienced on the labour ward. Support and resilience training could avoid suffering and consequences for professional carers. In a survey 15% of Swedish obstetricians and midwives reported PTSD symptoms after their worst obstetric event. © 2016 Royal College of Obstetricians and Gynaecologists.

Social Relationships, Gender, and Recovery From Mobility Limitation Among Older Americans.

PubMed

Latham, Kenzie; Clarke, Philippa J; Pavela, Greg

2015-09-01

Evidence suggests social relationships may be important facilitators for recovery from functional impairment, but the extant literature is limited in its measurement of social relationships including an over emphasis on filial social support and a paucity of nationally representative data. Using data from Waves 4-9 (1998-2008) of the Health and Retirement Study (HRS), this research examines the association between social relationships and recovery from severe mobility limitation (i.e., difficulty walking one block or across the room) among older Americans. Using a more nuanced measure of recovery that includes complete and partial recovery, a series of discrete-time event history models with multiple competing recovery outcomes were estimated using multinomial logistic regression. Providing instrumental support to peers increased the odds of complete and partial recovery from severe mobility limitation, net of numerous social, and health factors. Having relatives living nearby decreased the odds of complete recovery, while being engaged in one's neighborhood increased the odds of partial recovery. The influence of partner status on partial and complete recovery varied by gender, whereby partnered men were more likely to experience recovery relative to partnered women. The effect of neighborhood engagement on partial recovery also varied by gender. Disengaged women were the least likely to experience partial recovery compared with any other group. The rehabilitative potential of social relationships has important policy implications. Interventions aimed at encouraging older adults with mobility limitation to be engaged in their neighborhoods and/or provide instrumental support to peers may improve functional health outcomes. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Limiting severe outcomes and impact on intensive care units of moderate-intermediate 2009 pandemic influenza: role of infectious diseases units.

PubMed

Carbonara, Sergio; Bruno, Giuseppe; Ciaula, Giuseppe Di; Pantaleo, Anna Donata; Angarano, Gioacchino; Monno, Laura

2012-01-01

The rate of severe outcomes of patients with 2009 pandemic (A/H1N1) influenza (2009pI) hospitalized in non-intensive care units (ICUs) has not been defined thus far. This study aims to assess the efficacy of the management of patients with influenza-like illness (ILI) of moderate intermediate severity in an infectious diseases unit (IDU) during the first wave of 2009pI and its influence on the burden of ICUs. All patients hospitalized from October 27, 2009, to February 5, 2010, with ILI were included in this prospective observational study. The IDU was organized and the staff was trained to provide intermediate care; patients were transferred to the ICU only if they required invasive ventilation, extracorporeal membrane oxygenation, or advanced cardiovascular support. Demographic data, clinical presentation, coexisting medical conditions, and laboratory and radiological findings were recorded and analyzed, as well as treatment and outcome data. Overall, 108 patients (median age 36 years [IQR 27-54], 57.4% males) including 66.7% with ≥ 1 risk factor for severe influenza, 47.2% with confirmed 2009pI by RT-PCR and 63.9% with pneumonia, were enrolled in the study. All subjects received intravenous fluids and 83.3% were administered oseltamivir, 96.3% antibacterials, 19.4% oxygen therapy without ventilatory support, and 10.2% non-invasive ventilation. A total of 106 (98.1%) subjects were discharged after a 6-day median hospital stay [IQR 4-9]. Two patients (1.9%) were transferred to the ICU. There were no deaths. These results suggest that the aggressive treatment of patients with moderate intermediate severity 2009 pandemic ILI in non-ICU wards may result in a low rate of severe outcomes and brief hospitalization. IDUs, if properly organized for intermediate care, may efficiently provide correct disease management, in addition to complying with infection control requirements, thus reducing the burden of the pandemic on ICUs. Further studies are warranted to evaluate the outcome of patients with moderate intermediate 2009pI in different non-ICU settings.

Antagonistic versus non-antagonistic models of balancing selection: Characterizing the relative timescales and hitchhiking effects of partial selective sweeps

PubMed Central

Connallon, Tim; Clark, Andrew G.

2012-01-01

Antagonistically selected alleles -- those with opposing fitness effects between sexes, environments, or fitness components -- represent an important component of additive genetic variance in fitness-related traits, with stably balanced polymorphisms often hypothesized to contribute to observed quantitative genetic variation. Balancing selection hypotheses imply that intermediate-frequency alleles disproportionately contribute to genetic variance of life history traits and fitness. Such alleles may also associate with population genetic footprints of recent selection, including reduced genetic diversity and inflated linkage disequilibrium at linked, neutral sites. Here, we compare the evolutionary dynamics of different balancing selection models, and characterize the evolutionary timescale and hitchhiking effects of partial selective sweeps generated under antagonistic versus non-antagonistic (e.g., overdominant and frequency-dependent selection) processes. We show that that the evolutionary timescales of partial sweeps tend to be much longer, and hitchhiking effects are drastically weaker, under scenarios of antagonistic selection. These results predict an interesting mismatch between molecular population genetic and quantitative genetic patterns of variation. Balanced, antagonistically selected alleles are expected to contribute more to additive genetic variance for fitness than alleles maintained by classic, non-antagonistic mechanisms. Nevertheless, classical mechanisms of balancing selection are much more likely to generate strong population genetic signatures of recent balancing selection. PMID:23461340

Mechanisms of m-cresol induced protein aggregation studied using a model protein cytochrome c†

PubMed Central

Singh, Surinder M.; Hutchings, Regina L.; Mallela, Krishna M.G.

2014-01-01

Multi-dose protein formulations require an effective antimicrobial preservative (AP) to inhibit microbial growth during long-term storage of unused formulations. m-cresol is one such AP, but has been shown to cause protein aggregation. However, the fundamental physical mechanisms underlying such AP-induced protein aggregation are not understood. In this study, we used a model protein cytochrome c to identify the protein unfolding that triggers protein aggregation. m-cresol induced cytochrome c aggregation at preservative concentrations that are commonly used to inhibit microbial growth. Addition of m-cresol decreased the temperature at which the protein aggregated and increased the aggregation rate. However, m-cresol did not perturb the tertiary or secondary structure of cytochrome c. Instead, it populated an “invisible” partially unfolded intermediate where a local protein region around the methionine residue at position 80 was unfolded. Stabilizing the Met80 region drastically decreased the protein aggregation, which conclusively shows that this local protein region acts as an aggregation “hot-spot”. Based on these results, we propose that APs induce protein aggregation by partial rather than global unfolding. Because of the availability of site-specific probes to monitor different levels of protein unfolding, cytochrome c provided a unique advantage in characterizing the partial protein unfolding that triggers protein aggregation. PMID:21229618

Nitrogen removal from sludge digester liquids by nitrification/denitrification or partial nitritation/anammox: environmental and economical considerations.

PubMed

Fux, C; Siegrist, H

2004-01-01

In wastewater treatment plants with anaerobic sludge digestion, 15-20% of the nitrogen load is recirculated to the main stream with the return liquors from dewatering. Separate treatment of this ammonium-rich digester supernatant significantly reduces the nitrogen load of the activated sludge system. Two biological applications are considered for nitrogen elimination: (i) classical autotrophic nitrification/heterotrophic denitrification and (ii) partial nitritation/autotrophic anaerobic ammonium oxidation (anammox). With both applications 85-90% nitrogen removal can be achieved, but there are considerable differences in terms of sustainability and costs. The final gaseous products for heterotrophic denitrification are generally not measured and are assumed to be nitrogen gas (N2). However, significant nitrous oxide (N2O) production can occur at elevated nitrite concentrations in the reactor. Denitrification via nitrite instead of nitrate has been promoted in recent years in order to reduce the oxygen and the organic carbon requirements. Obviously this "achievement" turns out to be rather disadvantageous from an overall environmental point of view. On the other hand no unfavorable intermediates are emitted during anaerobic ammonium oxidation. A cost estimate for both applications demonstrates that partial nitritation/anammox is also more economical than classical nitrification/denitrification. Therefore autotrophic nitrogen elimination should be used in future to treat ammonium-rich sludge liquors.

Flow Generated by a Partially Penetrating Well in a Leaky Two-Aquifer System with a Storative Semiconfining Layer

NASA Astrophysics Data System (ADS)

Sepulveda, N.; Rohrer, K.

2008-05-01

The permeability of the semiconfining layers of the highly productive Floridan Aquifer System may be large enough to invalidate the assumptions of the leaky aquifer theory. These layers are the intermediate confining and the middle semiconfining units. The analysis of aquifer-test data with analytical solutions of the ground-water flow equation developed with the approximation of a low hydraulic conductivity ratio between the semiconfining layer and the aquifer may lead to inaccurate hydraulic parameters. An analytical solution is presented here for the flow in a confined leaky aquifer, the overlying storative semiconfining layer, and the unconfined aquifer, generated by a partially penetrating well in a two-aquifer system, and allowing vertical and lateral flow components to occur in the semiconfining layer. The equations describing flow caused by a partially penetrating production well are solved analytically to provide a method to accurately determine the hydraulic parameters in the confined aquifer, semiconfining layer, and unconfined aquifer from aquifer-test data. Analysis of the drawdown data from an aquifer test performed in central Florida showed that the flow solution presented here for the semiconfining layer provides a better match and a more unique identification of the hydraulic parameters than an analytical solution that considers only vertical flow in the semiconfining layer.

Lipids as Tumoricidal Components of Human α-Lactalbumin Made Lethal to Tumor Cells (HAMLET)

PubMed Central

Ho, James C. S.; Storm, Petter; Rydström, Anna; Bowen, Ben; Alsin, Fredrik; Sullivan, Louise; Ambite, Inès; Mok, K. H.; Northen, Trent; Svanborg, Catharina

2013-01-01

Long-chain fatty acids are internalized by receptor-mediated mechanisms or receptor-independent diffusion across cytoplasmic membranes and are utilized as nutrients, building blocks, and signaling intermediates. Here we describe how the association of long-chain fatty acids to a partially unfolded, extracellular protein can alter the presentation to target cells and cellular effects. HAMLET (human α-lactalbumin made lethal to tumor cells) is a tumoricidal complex of partially unfolded α-lactalbumin and oleic acid (OA). As OA lacks independent tumoricidal activity at concentrations equimolar to HAMLET, the contribution of the lipid has been debated. We show by natural abundance 13C NMR that the lipid in HAMLET is deprotonated and by chromatography that oleate rather than oleic acid is the relevant HAMLET constituent. Compared with HAMLET, oleate (175 μm) showed weak effects on ion fluxes and gene expression. Unlike HAMLET, which causes metabolic paralysis, fatty acid metabolites were less strongly altered. The functional overlap increased with higher oleate concentrations (500 μm). Cellular responses to OA were weak or absent, suggesting that deprotonation favors cellular interactions of fatty acids. Fatty acids may thus exert some of their essential effects on host cells when in the deprotonated state and when presented in the context of a partially unfolded protein. PMID:23629662

Rescattering Effects in the Hadronic-Light-by-Light Contribution to the Anomalous Magnetic Moment of the Muon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colangelo, Gilberto; Hoferichter, Martin; Procura, Massimiliano

We present a first model-independent calculation of ππ intermediate states in the hadronic-light-by-light (HLBL) contribution to the anomalous magnetic moment of the muon (g - 2) μ that goes beyond the scalar QED pion loop. To this end, we combine a recently developed dispersive description of the HLBL tensor with a partial-wave expansion and demonstrate that the known scalar-QED result is recovered after partial-wave resummation. Using dispersive fits to high-statistics data for the pion vector form factor, we provide an evaluation of the full pion box a π μ box = –15.9(2) x 10 -11. We then construct a suitablemore » input for the γ*γ* → ππ helicity partial waves, based on a pion-pole left-hand cut and show that for the dominant charged-pion contribution, this representation is consistent with the two-loop chiral prediction and the COMPASS measurement for the pion polarizability. This allows us to reliably estimate S-wave rescattering effects to the full pion box and leads to our final estimate for the sum of these two contributions a π μ box + a ππ,π-pole μ,J=0 LHC = –24(1) x 10 -11.« less

Rescattering Effects in the Hadronic-Light-by-Light Contribution to the Anomalous Magnetic Moment of the Muon

DOE PAGES

Colangelo, Gilberto; Hoferichter, Martin; Procura, Massimiliano; ...

2017-06-09

We present a first model-independent calculation of ππ intermediate states in the hadronic-light-by-light (HLBL) contribution to the anomalous magnetic moment of the muon (g - 2) μ that goes beyond the scalar QED pion loop. To this end, we combine a recently developed dispersive description of the HLBL tensor with a partial-wave expansion and demonstrate that the known scalar-QED result is recovered after partial-wave resummation. Using dispersive fits to high-statistics data for the pion vector form factor, we provide an evaluation of the full pion box a π μ box = –15.9(2) x 10 -11. We then construct a suitablemore » input for the γ*γ* → ππ helicity partial waves, based on a pion-pole left-hand cut and show that for the dominant charged-pion contribution, this representation is consistent with the two-loop chiral prediction and the COMPASS measurement for the pion polarizability. This allows us to reliably estimate S-wave rescattering effects to the full pion box and leads to our final estimate for the sum of these two contributions a π μ box + a ππ,π-pole μ,J=0 LHC = –24(1) x 10 -11.« less

How to assess driver's interaction with partially automated driving systems - A framework for early concept assessment.

PubMed

van den Beukel, Arie P; van der Voort, Mascha C

2017-03-01

The introduction of partially automated driving systems changes the driving task into supervising the automation with an occasional need to intervene. To develop interface solutions that adequately support drivers in this new role, this study proposes and evaluates an assessment framework that allows designers to evaluate driver-support within relevant real-world scenarios. Aspects identified as requiring assessment in terms of driver-support within the proposed framework are Accident Avoidance, gained Situation Awareness (SA) and Concept Acceptance. Measurement techniques selected to operationalise these aspects and the associated framework are pilot-tested with twenty-four participants in a driving simulator experiment. The objective of the test is to determine the reliability of the applied measurements for the assessment of the framework and whether the proposed framework is effective in predicting the level of support offered by the concepts. Based on the congruency between measurement scores produced in the test and scores with predefined differences in concept-support, this study demonstrates the framework's reliability. A remaining concern is the framework's weak sensitivity to small differences in offered support. The article concludes that applying the framework is especially advantageous for evaluating early design phases and can successfully contribute to the efficient development of driver's in-control and safe means of operating partially automated vehicles. Copyright © 2016 Elsevier Ltd. All rights reserved.

Policing in nonhuman primates: partial interventions serve a prosocial conflict management function in rhesus macaques.

PubMed

Beisner, Brianne A; McCowan, Brenda

2013-01-01

Studies of prosocial policing in nonhuman societies traditionally focus on impartial interventions because of an underlying assumption that partial support implies a direct benefit to the intervener, thereby negating the potential for being prosocial in maintaining social stability for the benefit of the group. However, certain types of partial interventions have significant potential to be prosocial in controlling conflict, e.g. support of non-kin subordinates. Here, we propose a policing support hypothesis that some types of agonistic support serve a prosocial policing function that maintains group stability. Using seven large captive groups of rhesus macaques, we investigated the relationship between intervention type and group-level costs and benefits (rates of trauma, severe aggression, social relocation) and individual level costs and benefits (preferential sex-dyad targeting, dominance ambiguity reduction, access to mates, and return aggression). Our results show that impartial interventions and support of subordinate non-kin represent prosocial policing as both (1) were negatively associated with group-level rates of trauma and severe aggression, respectively, (2) showed no potential to confer individual dominance benefits, (3) when performed outside the mating season, they did not increase chances of mating with the beneficiary, and (4) were low-cost for the highest-ranking interveners. We recommend expanding the definition of 'policing' in nonhumans to include these 'policing support interventions'.

A unified software framework for deriving, visualizing, and exploring abstraction networks for ontologies

PubMed Central

Ochs, Christopher; Geller, James; Perl, Yehoshua; Musen, Mark A.

2016-01-01

Software tools play a critical role in the development and maintenance of biomedical ontologies. One important task that is difficult without software tools is ontology quality assurance. In previous work, we have introduced different kinds of abstraction networks to provide a theoretical foundation for ontology quality assurance tools. Abstraction networks summarize the structure and content of ontologies. One kind of abstraction network that we have used repeatedly to support ontology quality assurance is the partial-area taxonomy. It summarizes structurally and semantically similar concepts within an ontology. However, the use of partial-area taxonomies was ad hoc and not generalizable. In this paper, we describe the Ontology Abstraction Framework (OAF), a unified framework and software system for deriving, visualizing, and exploring partial-area taxonomy abstraction networks. The OAF includes support for various ontology representations (e.g., OWL and SNOMED CT's relational format). A Protégé plugin for deriving “live partial-area taxonomies” is demonstrated. PMID:27345947

A unified software framework for deriving, visualizing, and exploring abstraction networks for ontologies.

PubMed

Ochs, Christopher; Geller, James; Perl, Yehoshua; Musen, Mark A

2016-08-01

Software tools play a critical role in the development and maintenance of biomedical ontologies. One important task that is difficult without software tools is ontology quality assurance. In previous work, we have introduced different kinds of abstraction networks to provide a theoretical foundation for ontology quality assurance tools. Abstraction networks summarize the structure and content of ontologies. One kind of abstraction network that we have used repeatedly to support ontology quality assurance is the partial-area taxonomy. It summarizes structurally and semantically similar concepts within an ontology. However, the use of partial-area taxonomies was ad hoc and not generalizable. In this paper, we describe the Ontology Abstraction Framework (OAF), a unified framework and software system for deriving, visualizing, and exploring partial-area taxonomy abstraction networks. The OAF includes support for various ontology representations (e.g., OWL and SNOMED CT's relational format). A Protégé plugin for deriving "live partial-area taxonomies" is demonstrated. Copyright © 2016 Elsevier Inc. All rights reserved.

Improved curvature-based inpainting applied to fine art: recovering van Gogh's partially hidden brush strokes

NASA Astrophysics Data System (ADS)

Kuang, Yubin; Stork, David G.; Kahl, Fredrik

2011-03-01

Underdrawings and pentimenti-typically revealed through x-ray imaging and infrared reflectography-comprise important evidence about the intermediate states of an artwork and thus the working methods of its creator.1 To this end, Shahram, Stork and Donoho introduced the De-pict algorithm, which recovers layers of brush strokes in paintings with open brush work where several layers are partially visible, such as in van Gogh's Self portrait with a grey felt hat.2 While that preliminary work served as a proof of concept that computer image analytic methods could recover some occluded brush strokes, the work needed further refinement before it could be a tool for art scholars. Our current work makes several steps to improve that algorithm. Specifically, we refine the inpainting step through the inclusion of curvature-based constraints, in which a mathematical curvature penalty biases the reconstruction toward matching the artist's smooth hand motion. We refine and test our methods using "ground truth" image data: passages of four layers of brush strokes in which the intermediate layers were recorded photographically. At each successive top layer (currently identified by the user), we used k-means clustering combined with graph cuts to obtain chromatically and spatially coherent segmentation of brush strokes. We then reconstructed strokes at the deeper layer with our new curvature-based inpainting algorithm based on chromatic level lines. Our methods are clearly superior to previous versions of the De-pict algorithm on van Gogh's works giving smoother, natural strokes that more closely match the shapes of unoccluded strokes. Our improved method might be applied to the classic drip paintings of Jackson Pollock, where the drip work is more open and the physics of splashing paint ensures that the curvature more uniform than in the brush strokes of van Gogh.

Meiotic competence of equine oocytes and pronucleus formation after intracytoplasmic sperm injection (ICSI) as related to granulosa cell apoptosis.

PubMed

Dell'Aquila, Maria Elena; Albrizio, Maria; Maritato, Filippo; Minoia, Paolo; Hinrichs, Katrin

2003-06-01

Follicle atresia and granulosa cell apoptosis may be related to oocyte meiotic and developmental competence. We analyzed the relationships among granulosa cell apoptosis, initial cumulus morphology, oocyte nuclear maturation in vitro, and pronucleus formation after intracytoplasmic sperm injection (ICSI) in the horse. For each follicle, the size was measured and granulosa cells were used for DNA laddering analysis. Oocytes were evaluated for cumulus morphology, cultured for in vitro maturation, and submitted to ICSI. Apoptosis was categorized as absent, intermediate, or advanced according to the relative concentrations of two DNA fragments at 900 and 360 base pairs (bp). In 98 oocyte-follicle pairs, 52 oocytes were classified as expanded (Exp), 39 as compact (Cp), and 7 as having a partial (P) cumulus. Advanced apoptosis was detected in 55% (54/98) of follicles; 37% (36/98) of follicles showed an intermediate level of apoptosis; and 8 follicles (8%) were nonapoptotic. Follicle size was not significantly correlated with granulosa cell apoptosis (P > 0.05). Significantly more Exp than Cp oocytes originated from follicles with advanced apoptosis (P < 0.001). The proportion of oocytes maturing in vitro was significantly higher in oocytes issuing from apoptotic follicles than in oocytes issuing from healthy follicles (P < 0.05). The proportion of normally (two pronuclei) or abnormally fertilized oocytes (one or greater than two pronuclei, or partially decondensed sperm) did not differ in relation to granulosa cell apoptosis. We conclude that, in the mare, granulosa cell apoptosis is related to cumulus expansion and an increase in oocyte meiotic competence but has no effect on the proportion of meiotically competent oocytes that activate after ICSI. These results provide selection criteria for horse oocytes used in assisted reproductive techniques so that embryo production may be maximized.

Effects of an irregular bedtime schedule on sleep quality, daytime sleepiness, and fatigue among university students in Taiwan.

PubMed

Kang, Jiunn-Horng; Chen, Shih-Ching

2009-07-19

An irregular bedtime schedule is a prevalent problem in young adults, and could be a factor detrimentally affecting sleep quality. The goal of the present study was to explore the association between an irregular bedtime schedule and sleep quality, daytime sleepiness, and fatigue among undergraduate students in Taiwan. A total of 160 students underwent a semi-structured interview and completed a survey comprising 4 parts: Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Fatigue Severity Scale (FSS), and a rating of irregular bedtime frequency. Participants were grouped into 3 groups in terms of irregular bedtime frequency: low, intermediate, or high according to their 2-week sleep log. To screen for psychological disorders or distress that may have affected responses on the sleep assessment measures, the Chinese health questionnaire-12 (CHQ-12) was also administered. We found an increase in bedtime schedule irregularity to be significantly associated with a decrease in average sleep time per day (Spearman r = -0.22, p = 0.05). Multivariate regression analysis revealed that irregular bedtime frequency and average sleep time per day were correlated with PSQI scores, but not with ESS or FSS scores. A significant positive correlation between irregular bedtime frequency and PSQI scores was evident in the intermediate (partial r = 0.18, p = 0.02) and high (partial r = 0.15, p = 0.05) frequency groups as compared to low frequency group. The results of our study suggest a high prevalence of both an irregular bedtime schedule and insufficient sleep among university students in Taiwan. Students with an irregular bedtime schedule may experience poor sleep quality. We suggest further research that explores the mechanisms involved in an irregular bedtime schedule and the effectiveness of interventions for improving this condition.