Eggshell membrane as a novel bio sorbent for remediation of boron from desalinated water.

PubMed

Al-Ghouti, Mohammad A; Khan, Mariam

2018-02-01

This study investigated the use of eggshell membrane (ESM) as a bio-sorbent and the effect of temperature, pH, and initial concentration on its efficiency. Furthermore, by altering the chemical composition, modified eggshell membrane (MESM) was prepared, and its efficiency was compared with the ESM. Results showed that the adsorption of boron preferred an acidic condition; pH 6 at 35 °C. In addition, the positive value of ΔH° suggested that the reaction favored endothermic pathway, while the negative value for ΔG° further suggested that the adsorption process was spontaneous. Furthermore, the ESM could adsorb 97% of boron, while MESM was able to adsorb 95%. From the Fourier transform infrared (FTIR), different functional groups were recorded on the surface of the ESM and MESM, and they played key role in the boron adsorption mechanisms. Linear Freundlich model was suggested to best describe the experimental data with 99.4% correlation coefficient. Copyright © 2017 Elsevier Ltd. All rights reserved.

Integrated proteomic and transcriptomic analysis of the Aedes aegypti eggshell

PubMed Central

2014-01-01

Background Mosquito eggshells show remarkable diversity in physical properties and structure consistent with adaptations to the wide variety of environments exploited by these insects. We applied proteomic, transcriptomic, and hybridization in situ techniques to identify gene products and pathways that participate in the assembly of the Aedes aegypti eggshell. Aedes aegypti population density is low during cold and dry seasons and increases immediately after rainfall. The survival of embryos through unfavorable periods is a key factor in the persistence of their populations. The work described here supports integrated vector control approaches that target eggshell formation and result in Ae. aegypti drought-intolerant phenotypes for public health initiatives directed to reduce mosquito-borne diseases. Results A total of 130 proteins were identified from the combined mass spectrometric analyses of eggshell preparations. Conclusions Classification of proteins according to their known and putative functions revealed the complexity of the eggshell structure. Three novel Ae. aegypti vitelline membrane proteins were discovered. Odorant-binding and cysteine-rich proteins that may be structural components of the eggshell were identified. Enzymes with peroxidase, laccase and phenoloxidase activities also were identified, and their likely involvements in cross-linking reactions that stabilize the eggshell structure are discussed. PMID:24707823

Highly Efficient Catalysis of Azo Dyes Using Recyclable Silver Nanoparticles Immobilized on Tannic Acid-Grafted Eggshell Membrane

NASA Astrophysics Data System (ADS)

Liu, Xiaojing; Liang, Miao; Liu, Mingyue; Su, Rongxin; Wang, Mengfan; Qi, Wei; He, Zhimin

2016-10-01

In this study, a facile one-step synthesis of a novel nanocomposite catalytic film was developed based on silver nanoparticles (AgNPs) immobilized in tannic acid-modified eggshell membrane (Tan-ESM). Tannic acid, as a typical plant polyphenol from oak wood, was first grafted onto ESM fibers to serve as both the reductant and the stabilizer during the synthesis of AgNPs. The morphology, constitution, and thermal stability of the resulting AgNPs@Tan-ESM composites were fully characterized to explain the excellent catalytic efficiency of AgNPs@Tan-ESM composites. These composite catalysts were applied to the degradation of azo dyes which exhibited the high catalytic activity toward Congo red and methyl orange according to the kinetic curves. More importantly, they can be easily recovered and reused for many times because of their good stability.

Hierarchical structure and mechanical properties of snake (Naja atra) and turtle (Ocadia sinensis) eggshells.

PubMed

Chang, Yin; Chen, Po-Yu

2016-02-01

After hundreds of million years of evolution, natural armors have evolved in various organisms, and has manifested in diverse forms such as eggshells, abalone shells, alligator osteoderms, turtle shells, and fish scales. Eggshells serve as multifunctional shields for successful embryogenesis, such as protection, moisture control and thermal regulation. Unlike calcareous avian eggshells which are brittle and hard, reptilians have leathery eggshells that are tough and flexible. Reptilian eggshells can withstand collision damages when laid in holes and dropped onto each other, and reduce abrasion caused by buried sand. In this study, we investigate structure and mechanical properties of eggshells of Taiwan cobra snake (Naja atra) and Chinese striped-neck turtle (Ocadia sinensis). From Acid Fuchsin Orange G (AFOG) staining and ATR-FTIR examination, we found that both eggshells are mainly composed of keratin. The mechanical properties of demineralized snake and turtle eggshells were evaluated by tensile and fracture tests and show distinctly difference. Turtle eggshells are relatively stiff and rigid, while snake eggshells behave as elastomers, which are highly extensible and reversible. The exceptional deformability (110-230% tensile strain) and toughness of snake eggshells are contributed by the wavy and random arrangement of keratin fibers as well as collagen layers. Multi-scale toughening mechanisms of snake eggshells were observed and elucidated, including crack deflection and twisting, fibers reorientation, sliding and bridging, inter-laminar shear effect, as well as the α-β phase transition of keratin. Inspirations from the structural and mechanical designs of reptilian eggshells may lead to the synthesis of tough, extensible, lightweight composites which could be further applied in the flexible devices, packaging and bio-medical fields. Amniotic eggshells serve as multifunctional shields for successful embryogenesis. The avian eggshells have been extensively studied while there are very few studies on reptilian eggshells and most of them focused on mineralization and embryotic development. For the first time, the hierarchical structure and mechanical properties of snake and turtle eggshells are comprehensively and comparatively studied. Both snake and turtle eggshells are multilayer, hierarchically-structured composites consisting mainly of keratin yet their mechanical behaviors are distinctly different. Turtle eggshells are stiff and rigid, while snake eggshells are highly extensible (>200%) and reversible due to multiple deformation stages, phase transition of keratin and various toughening mechanisms. We believe that this study will make positive scientific impact and interest the broad and multidisciplinary readership. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Protein profiles of hatchery egg shell membrane

USDA-ARS?s Scientific Manuscript database

Background: Eggshells, which consist largely of calcareous outer shell and shell membranes, constitute a significant part of poultry hatchery waste. The shell membranes (ESM) not only contain proteins that originate from egg whites but also from the developing embryos and different contaminants of m...

An Efficient Method for Co-purification of Eggshell Matrix Proteins OC-17, OC-116, and OCX-36

PubMed Central

2016-01-01

In this study, we improved the eggshell-membrane separation process by separating the shell and membrane with EDTA solution, evaluating effects of three different extraction solutions (acetic acid, EDTA, and phosphate solution), and co-purifying multiple eggshell proteins with two successive ion-exchange chromatography procedures (CM Sepharose Fast Flow and DEAE Sepharose Fast Flow). The recovery and residual rates of eggshell and membrane separated by the modified method with added EDTA solution were 93.88%, 91.15% and 1.01%, 2.87%, respectively. Ovocleidin-116 (OC-116) and ovocalyxin-36 (OCX-36) were obtained by loading 50 mM Na-Hepes, pH 7.5, 2 mM DTT and 350 mM NaCl buffer onto the DEAE-FF column at a flow rate of 1 mL/min, ovocleidin-17 (OC-17) was obtained by loading 100 mM NaCl, 50 mM Tris, pH 8.0 on the CM-FF column at a flow rate of 0.5 mL/min. The purities of OCX-36, OC-17 and OC-116 were 96.82%, 80.15% and 73.22%, and the recovery rates were 55.27%, 53.38% and 36.34%, respectively. Antibacterial activity test suggested that phosphate solution extract exhibited significantly higher activity against the tested bacterial strains than the acetic acid or EDTA extract, probably due to more types of proteins in the extract. These results demonstrate that this separation method is feasible and efficient. PMID:28115888

Nutritional effects of egg shell membrane supplements on chicken performance and immunity

USDA-ARS?s Scientific Manuscript database

Eggshell membranes (ESM) contain a variety of proteins and peptides which help in the development of embryo and provide protection to it. Many of the peptides and proteins associated with ESM have antimicrobial, immune-modulatory, and adjuvant properties. We hypothesized that the membrane byproducts...

A study on production of biodiesel using a novel solid oxide catalyst derived from waste.

PubMed

Majhi, Samrat; Ray, Srimanta

2016-05-01

The issues of energy security, dwindling supply and inflating price of fossil fuel have shifted the global focus towards fuel of renewable origin. Biodiesel, having renewable origin, has exhibited great potential as substitute for fossil fuels. The most common route of biodiesel production is through transesterification of vegetable oil in presence of homogeneous acid or base or solid oxide catalyst. But, the economics of biodiesel is not competitive with respect to fossil fuel due to high cost of production. The vegetable oil waste is a potential alternative for biodiesel production, particularly when disposal of used vegetable oil has been restricted in several countries. The present study evaluates the efficacy of a low-cost solid oxide catalyst derived from eggshell (a food waste) in transesterification of vegetable oil and simulated waste vegetable oil (SWVO). The impact of thermal treatment of vegetable oil (to simulate frying operation) on transesterification using eggshell-derived solid oxide catalyst (ESSO catalyst) was also evaluated along with the effect of varying reaction parameters. The study reported that around 90 % biodiesel yield was obtained with vegetable oil at methanol/oil molar ratio of 18:1 in 3 h reaction time using 10 % ESSO catalyst. The biodiesel produced with ESSO catalyst from SWVO, thermally treated at 150 °C for 24 h, was found to conform with the biodiesel standard, but the yield was 5 % lower compared to that of the untreated oil. The utilization of waste vegetable oil along with waste eggshell as catalyst is significant for improving the overall economics of the biodiesel in the current market. The utilization of waste for societal benefit with the essence of sustainable development is the novelty of this work.

The influence of chicken eggshell powder as a buffer on biohydrogen production from rotten orange (Citrus nobilis var. microcarpa) with immobilized mixed culture

NASA Astrophysics Data System (ADS)

Damayanti, Astrilia; Sarto, Syamsiah, Siti; Sediawan, Wahyudi B.

2017-06-01

This research observed the influence of chicken eggshell on hydrogen production from anaerobic fermentation of rotten orange (Citrus nobilis var. microcarpa) using batch method at 36 °C and pH 7. Fermentation material were varied in several types, the first type was meat and peel of oranges with VS of 59.152 g.L-1 in A, B, C, and D compositions. The second type was orange meat added with peel (OMP) with VS of 36.852 g.L-1. The immobilized ingredients used in the experiment consisted of 2 % (w/v) alginate and active carbon with the ratio of 1:1. 3.2 g chicken eggshell powder was added to the first type of material (substrates A, B, C, and D). Results showed that pH during fermentation process using chicken eggshell as a buffer was constant at 5.5; however, without the use of chicken eggshell, the pH decreased to 3.8 and increased slightly before it stayed stable at 4.0. The total amount of gas produced in sample using the chicken eggshell was 46,35 mL.mg VS-1 and in sample produced without the eggshell, it was 3,4 mL.mg VS-1. The production of hydrogen in substrate that used chicken eggshell was 1,276 mL.gVS-1 in average on the first day. Meanwhile, for the substrate with no addition of chicken eggshell, the average production of hydrogen was 0,163 mL.gVS-1. The reduction of volatile solid (VS) in sample that used chicken eggshell was 24 %, while in sample produced without addition of chicken eggshell, the reduction was 12 %. The liquid compounds (VFA) produced in the fermentation using chicken eggshell were acetic acid and butyric acid. Meanwhile, without addition of chicken eggshell, the products were acetic acid, butyric acid, and propionic acid. This study shows that addition of chicken eggshell as a buffer effectively contributed to hydrogen production during fermentation of rotten oranges.

Comparative evaluation of air cell and eggshell temperature measurement methodologies used in broiler hatching eggs during late incubation.

PubMed

Peebles, E D; Zhai, W; Gerard, P D

2012-07-01

The current study was conducted to compare and contrast the uses of 2 devices (temperature transponder or infrared thermometer) and their locations (inner air cell membrane or outer eggshell surface) in Ross × Ross 708 broiler hatching eggs. The air cells of 14 embryonated and 10 nonembryonated eggs were implanted with temperature transponders on d 13.5 of incubation. Likewise, for these same eggs, eggshell surface temperature was detected with the use of transponders and an infrared thermometer. Temperatures were recorded every 12 h between 14.5 and 18 d of incubation, and graphs and corresponding regression values were used to track the temperatures over these time periods. The temperature readings using all methods in embryonated and nonembryonated eggs were positively correlated. In nonembryonated eggs, temperatures in the air cell and on the eggshell surface using transponders were higher than those on the eggshell surface using an infrared thermometer. Mean air cell temperature readings of embryonated eggs using transponders were higher than those of the eggshell, as determined with the use of transponders or an infrared thermometer. Furthermore, the differences in air cell temperature using transponders and eggshell temperature using an infrared thermometer in embryonated eggs increased with embryonic age. These readings confirmed increased embryo heat production during the incubational period examined. It was further concluded that when compared with actual embryo body temperatures determined in previous studies, the use of transponders in the air cells of broiler hatching eggs detected a higher and closer temperature than eggshell surface temperature. It is suggested that the air cell transponders in embryonated eggs circumvented the confounding effects of the thermal barrier properties of the eggshell and the flow of air across its surface.

Sulfur-based autotrophic denitrification with eggshell for nitrate-contaminated synthetic groundwater treatment.

PubMed

Xu, Yaxian; Chen, Nan; Feng, Chuanping; Hao, Chunbo; Peng, Tong

2016-12-01

Eggshell is considered to be a waste and a significant quantity of eggshell waste is generated from food processing, baking and hatching industries. In this study, the effect of different sulfur/eggshell (w/w) ratios and temperatures was investigated to evaluate the feasibility of the sulfur-based autotrophic denitrification with eggshell (SADE) process for nitrate removal. The results showed eggshell can maintain a neutral condition in a range of pH 7.05-7.74 in the SADE process, and remove 97% of nitrate in synthetic groundwater. Compared with oyster shell and limestone, eggshell was found to be a desirable alkaline material for sulfur-based autotrophic denitrification (SAD) with no nitrite accumulation and insignificant sulfate production. Denitrification reaction was found to follow the first-order kinetic models (R(2) > .9) having nitrate removal rate constants of 0.85 and 0.93 d(-1) for raw eggshell and boiled eggshell, respectively. Sulfur/eggshell ratio of 2:3 provided the best efficiency on nitrate removal. Nitrate was removed completely by the SADE process at a low temperature of 15°C. Eggshell could be used for the SAD process due to its good effect for nitrate removal from groundwater.

An insight into the heat and mass transfer mechanisms of eggshells hatching broiler chicks and its effects to the hatcher environment.

PubMed

Romanini, C E B; Exadaktylos, V; Hong, S W; Tong, Q; McGonnell, I; Demmers, T G M; Bergoug, H; Guinebretière, M; Eterradossi, N; Roulston, N; Verhelst, R; Bahr, C; Berckmans, D

2015-02-01

Thermodynamic study of incubated eggs is an important component in the optimisation of incubation processes. However, research on the interaction of heat and moisture transfer mechanisms in eggs is rather limited and does not focus on the hatching stage of incubation. During hatch, both the recently hatched chick and the broken eggshell add extra heat and moisture contents to the hatcher environment. In this study, we have proposed a novel way to estimate thermodynamically the amount of water evaporated from a broken eggshell during hatch. The hypothesis of this study considers that previously reported drops in eggshell temperature during hatching of chicks is the result remaining water content evaporating from the eggshell, released on the inner membrane by the recently hatched wet chick, just before hatch. To reproduce this process, water was sprayed on eggshells to mimic the water-fluid from the wet body of a chick. For each sample of eggshell, the shell geometry and weight, surface area and eggshell temperature were measured. Water evaporation losses and convection coefficient were calculated using a novel model approach considering the simultaneous heat and mass transfer profiles in an eggshell. The calculated average convective coefficient was 23.9 ± 7.5 W/m(2) °C, similar to previously reported coefficients in literature as a function of 0.5-1m/s air speed range. Comparison between measured and calculated values for the water evaporation showed 68% probability accuracy, associated to the use of an experimentally derived single heat transfer coefficient. The results support our proposed modelling approach of heat and mass transfer mechanisms. Furthermore, by estimating the amount of evaporated water in an eggshell post-hatch, air humidity levels inside the hatcher can be optimised to ensure wet chicks dry properly while not dehydrating early hatching chicks. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of antimicrobial peptide on dynamics of phosphocholine membrane: role of cholesterol and physical state of bilayer

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

Sharma, Veerendra K.; Mamontov, Eugene; Anunciado, Divina B.

Antimicrobial peptides are universal in all forms of life and are well known for their strong interaction with the cell membrane. This makes them a popular target for investigation of peptide-lipid interactions. Here we report the effect of melittin, an important antimicrobial peptide, on the dynamics of membranes based on 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) lipid in both the solid gel and fluid phases. To probe the phase transition, elastic neutron intensity temperature scans have been carried out on DMPC-based unilamellar vesicles (ULV) with and without melittin. We have found that addition of a small amount (0.2 mol%) melittin eliminates the steep fallmore » in the elastic intensity at 296 K associated with the solid gel to fluid phase transition, which is observed for pure DMPC vesicles. Quasielastic neutron scattering (QENS) experiments have been carried out on DMPC ULV in the solid gel and fluid phases with and without 0.2 mol % melittin. The data analysis invariably shows the presence of lateral and internal motions of the DMPC molecule. We found that melittin does have a profound effect on the dynamics of lipid molecules, especially on the lateral motion, and affects it in a different way, depending on the phase of the bilayers. In the solid gel phase, it acts as a plasticizer, enhancing the lateral motion of DMPC. However, in the fluid phase it acts as a stiffening agent, restricting the lateral motion of the lipid molecules. These observations are consistent with the mean squared displacements extracted from the elastic intensity temperature scans. Cholesterol is a vital component of eukaryotic membrane, which is a natural target for melittin. To investigate the effect of melittin on vesicles supplemented with cholesterol, QENS experiments have also been carried out on DMPC ULV with 20 mol% cholesterol in the presence and absence of 0.2 mol% melittin. Remarkably, the effects of melittin on the membrane dynamics disappear in the presence of 20 mol % cholesterol. Thus, our measurements indicate that the destabilizing effect of the peptide melittin on membranes can be mitigated by the presence of cholesterol.« less

Effect of antimicrobial peptide on dynamics of phosphocholine membrane: role of cholesterol and physical state of bilayer

DOE PAGES

Sharma, Veerendra K.; Mamontov, Eugene; Anunciado, Divina B.; ...

2015-06-24

Antimicrobial peptides are universal in all forms of life and are well known for their strong interaction with the cell membrane. This makes them a popular target for investigation of peptide-lipid interactions. Here we report the effect of melittin, an important antimicrobial peptide, on the dynamics of membranes based on 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) lipid in both the solid gel and fluid phases. To probe the phase transition, elastic neutron intensity temperature scans have been carried out on DMPC-based unilamellar vesicles (ULV) with and without melittin. We have found that addition of a small amount (0.2 mol%) melittin eliminates the steep fallmore » in the elastic intensity at 296 K associated with the solid gel to fluid phase transition, which is observed for pure DMPC vesicles. Quasielastic neutron scattering (QENS) experiments have been carried out on DMPC ULV in the solid gel and fluid phases with and without 0.2 mol % melittin. The data analysis invariably shows the presence of lateral and internal motions of the DMPC molecule. We found that melittin does have a profound effect on the dynamics of lipid molecules, especially on the lateral motion, and affects it in a different way, depending on the phase of the bilayers. In the solid gel phase, it acts as a plasticizer, enhancing the lateral motion of DMPC. However, in the fluid phase it acts as a stiffening agent, restricting the lateral motion of the lipid molecules. These observations are consistent with the mean squared displacements extracted from the elastic intensity temperature scans. Cholesterol is a vital component of eukaryotic membrane, which is a natural target for melittin. To investigate the effect of melittin on vesicles supplemented with cholesterol, QENS experiments have also been carried out on DMPC ULV with 20 mol% cholesterol in the presence and absence of 0.2 mol% melittin. Remarkably, the effects of melittin on the membrane dynamics disappear in the presence of 20 mol % cholesterol. Thus, our measurements indicate that the destabilizing effect of the peptide melittin on membranes can be mitigated by the presence of cholesterol.« less

Eggshell membrane biomaterial as a platform for applications in materials science.

PubMed

Baláž, Matej

2014-09-01

Eggshell membrane (ESM) is a unique biomaterial, which is generally considered as waste. However, it has extraordinary properties which can be utilized in various fields and its potential applications are therefore now being widely studied. The first part of this review focuses on the chemical composition and morphology of ESM. The main areas of ESM application are discussed in the second part. These applications include its utilization as a biotemplate for the synthesis of nanoparticles; as a sorbent of heavy metals, organics, dyes, sulfonates and fluorides; as the main component of biosensors; in medicine; and various other applications. For each area of interest, a detailed literature survey is given. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

The synthesis of 2-(5-(3-methoxyphenyl)-4,5-dihydro-1H-pyrazol-3-yl)phenol using sodium impregnated on activated chicken eggshells catalyst

NASA Astrophysics Data System (ADS)

Mardiana, L.; Bakri, R.; Septiarti, A.; Ardiansah, B.

2017-04-01

The novel compound of 2-(5-(3-methoxyphenyl)-4,5-dihydro-1H-pyrazol-3-yl)phenol as a pyrazoline derivative has been synthesized by two-steps reaction using sodium impregnated on activated chicken eggshells (Na-ACE) catalyst. Na-ACE was primarily prepared by a simple wet impregnation of NaOH solution on activated chicken eggshells solid support. The Na-ACE catalyst produced was characterized using FTIR spectrophotometer, XRD and SEM then applied in pyrazoline synthesis. First, chalcone was prepared from the reaction of 2-hydroxyacetophenone and 3-methoxybenzaldehyde by base-catalyzed aldol condensation. This product was subsequently reacted with hydrazine hydrate to give corresponding pyrazoline. The structure elucidation of the compound using FTIR, UV-Vis, LC-ESI-MS and 1H-NMR indicated the desired product has been successfully synthesized. Furthermore, the potential antioxidant activities of chalcone and pyrazoline have also been studied in-vitro using DPPH radical scavenging method. The results revealed that pyrazoline has a greater antioxidant activity than chalcone.

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

Jenkins, T.F.; Thorne, P.G.; Myers, K.F.

Salting-out solvent extraction (SOE) was compared with cartridge and membrane solid-phase extraction (SPE) for preconcentration of nitroaromatics, nitramines, and aminonitroaromatics prior to determination by reversed-phase high-performance liquid chromatography. The solid phases used were manufacturer-cleaned materials, Porapak RDX for the cartridge method and Empore SDB-RPS for the membrane method. Thirty-three groundwater samples from the Naval Surface Warfare Center, Crane, Indiana, were analyzed using the direct analysis protocol specified in SW846 Method 8330, and the results were compared with analyses conducted after preconcentration using SOE with acetonitrile, cartridge-based SPE, and membrane-based SPE. For high-concentration samples, analytical results from the three preconcentration techniquesmore » were compared with results from the direct analysis protocol; good recovery of all target analytes was achieved by all three pre-concentration methods. For low-concentration samples, results from the two SPE methods were correlated with results from the SOE method; very similar data was obtained by the SOE and SPE methods, even at concentrations well below 1 microgram/L.« less

Sulfation of Eggshell Proteins by Pipe Defines Dorsal-Ventral Polarity in the Drosophila embryo

PubMed Central

Zhang, Zhenyu; Stevens, Leslie M.; Stein, David

2009-01-01

Summary Drosophila embryonic dorsal-ventral (DV) polarity is controlled by a group of sequentially acting serine proteases located in the fluid-filled perivitelline space between the embryonic membrane and the eggshell, which generate the ligand for the Toll receptor on the ventral side of the embryo [1, 2, 3]. Spatial control of the protease cascade relies on the Pipe sulfotransferase, a fly homologue of vertebrate glycosaminoglycan modifying enzymes [4, 5, 6], which is expressed in ventral cells of the follicular epithelium surrounding the developing oocyte. The identification of the Pipe enzymatic target has remained a major gap in our understanding of the mechanism controlling the perivitelline protease cascade, and hence embryonic DV patterning. Here we show that the protein Vitelline Membrane-Like (VML) [7] undergoes Pipe-dependent sulfation and, consistent with a role in conveying positional information from the egg chamber to the embryo, becomes incorporated into the eggshell at a position corresponding to the location of the follicle cells from which it was secreted. Although VML influences embryonic DV pattern in a sensitized genetic background, VML is not essential for DV axis formation, suggesting that there is redundancy in the composition of the Pipe enzymatic target. Correspondingly, we find that additional structural components of the vitelline membrane undergo Pipe-dependent sulfation. In identifying the elusive targets of Pipe, this ork points to the vitelline membrane as the source of signals that generate the Drosophila DV axis and provides a framework for understanding the mechanism controlling spatially-specific activation of serine protease activity during embryonic pattern formation. PMID:19540119

Electrochemical vapor deposition of semiconductors from gas phase with a solid membrane cell.

PubMed

Cho, Sung Ki; Fan, Fu-Ren F; Bard, Allen J

2015-05-27

We demonstrate the feasibility of semiconductor deposition via the electrochemical reduction of gaseous precursors by the use of an anhydrous proton-conducting membrane, the solid acid CsHSO4, at 165 °C. This membrane electrode assembly was operated within the oxidation of hydrogen on a porous Pt anode and the deposition of Si or Ge under bias at the cathode from chloride-based gaseous precursors; SiCl4 and GeCl4 in an Ar flow with a reduction potential over -1.0 V (vs RHE).

The cuticle modulates ultraviolet reflectance of avian eggshells

PubMed Central

Fecheyr-Lippens, Daphne C.; Igic, Branislav; D'Alba, Liliana; Hanley, Daniel; Verdes, Aida; Holford, Mande; Waterhouse, Geoffrey I. N.; Grim, Tomas; Hauber, Mark E.; Shawkey, Matthew D.

2015-01-01

ABSTRACT Avian eggshells are variedly coloured, yet only two pigments, biliverdin and protoporphyrin IX, are known to contribute to the dramatic diversity of their colours. By contrast, the contributions of structural or other chemical components of the eggshell are poorly understood. For example, unpigmented eggshells, which appear white to the human eye, vary in their ultraviolet (UV) reflectance, which may be detectable by birds. We investigated the proximate mechanisms for the variation in UV-reflectance of unpigmented bird eggshells using spectrophotometry, electron microscopy, chemical analyses, and experimental manipulations. We specifically tested how UV-reflectance is affected by the eggshell cuticle, the outermost layer of most avian eggshells. The chemical dissolution of the outer eggshell layers, including the cuticle, increased UV-reflectance for only eggshells that contained a cuticle. Our findings demonstrate that the outer eggshell layers, including the cuticle, absorb UV-light, probably because they contain higher levels of organic components and other chemicals, such as calcium phosphates, compared to the predominantly calcite-based eggshell matrix. These data highlight the need to examine factors other than the known pigments in studies of avian eggshell colour. PMID:25964661

Palisade is required in the Drosophila ovary for assembly and function of the protective vitelline membrane.

PubMed

Elalayli, Maggie; Hall, Jacklyn D; Fakhouri, Mazen; Neiswender, Hannah; Ellison, Tambrea T; Han, Zhe; Roon, Penny; LeMosy, Ellen K

2008-07-15

The innermost layer of the Drosophila eggshell, the vitelline membrane, provides structural support and positional information to the embryo. It is assembled in an incompletely understood manner from four major proteins to form a homogeneous, transparent extracellular matrix. Here we show that RNAi knockdown or genetic deletion of a minor constituent of this matrix, Palisade, results in structural disruptions during the initial synthesis of the vitelline membrane by somatic follicle cells surrounding the oocyte, including wide size variation among the precursor vitelline bodies and disorganization of follicle cell microvilli. Loss of Palisade or the microvillar protein Cad99C results in abnormal uptake into the oocyte of sV17, a major vitelline membrane protein, and defects in non-disulfide cross-linking of sV17 and sV23, while loss of Palisade has additional effects on processing and disulfide cross-linking of these proteins. Embryos surrounded by the abnormal vitelline membranes synthesized when Palisade is reduced are fertilized but undergo developmental arrest, usually during the first 13 nuclear divisions, with a nuclear phenotype of chromatin margination similar to that described for wild-type embryos subjected to anoxia. Our results demonstrate that Palisade is involved in coordinating assembly of the vitelline membrane and is required for functional properties of the eggshell.

Palisade is required in the Drosophila ovary for assembly and function of the protective vitelline membrane

PubMed Central

Elalayli, Maggie; Hall, Jacklyn D.; Fakhouri, Mazen; Neiswender, Hannah; Ellison, Tambrea T.; Han, Zhe; Roon, Penny; LeMosy, Ellen K.

2008-01-01

The innermost layer of the Drosophila eggshell, the vitelline membrane, provides structural support and positional information to the embryo. It is assembled in an incompletely understood manner from four major proteins to form a homogeneous, transparent extracellular matrix. Here we show that RNAi knockdown or genetic deletion of a minor constituent of this matrix, Palisade, results in structural disruptions during the initial synthesis of the vitelline membrane by somatic follicle cells surrounding the oocyte, including wide size variation among the precursor vitelline bodies and disorganization of follicle cell microvilli. Loss of Palisade or the microvillar protein Cad99C results in abnormal uptake into the oocyte of sV17, a major vitelline membrane protein, and defects in non-disulfide cross-linking of sV17 and sV23, while loss of Palisade has additional effects on processing and disulfide cross-linking of these proteins. Embryos surrounded by the abnormal vitelline membranes synthesized when Palisade is reduced are fertilized but undergo developmental arrest, usually during the first 13 nuclear divisions, with a nuclear phenotype of chromatin margination similar to that described for wild-type embryos subjected to anoxia. Our results demonstrate that Palisade is involved in coordinating assembly of the vitelline membrane and is required for functional properties of the eggshell. PMID:18514182

Bilayer membrane interactions with nanofabricated scaffolds

DOE PAGES

Collier, C. Patrick

2015-07-29

Membrane function is facilitated by lateral organization within the lipid bilayer, including phase-separation of lipids into more ordered domains (lipid rafts) and anchoring of the membrane to a cytoskeleton. These features have proven difficult to reproduce in model membrane systems such as black lipid membranes, unilamellar vesicles and supported bilayers. However, advances in micro/nanofabrication have resulted in more realistic synthetic models of membrane-cytoskeleton interactions that can help uncover the design rules responsible for biological membrane formation and organization. This review will focus on describing micro-/nanostructured scaffolds that can emulate the connections of a cellular membrane to an underlying “cytoskeleton”. Thismore » includes molecular-based scaffolds anchored to a solid substrate through surface chemistry, solid-state supports modified by material deposition, lithography and etching, the creation of micro/nanoporous arrays, integration with microfluidics, and droplet-based bilayers at interfaces. Lastly, model systems such as these are increasing our understanding of structure and organization in cell membranes, and how they result in the emergence of functionality at the nanoscale.« less

Synthesis and adsorption properties of flower-like layered double hydroxide by a facile one-pot reaction with an eggshell membrane as assistant

NASA Astrophysics Data System (ADS)

Li, Songnan; Zhang, Jiawei; Jamil, Saba; Cai, Qinghai; Zang, Shuying

In this paper, flower-like layered double hydroxides were synthesized with eggshell membrane assistant. The as-prepared samples were characterized by a series of techniques including X-ray diffraction (XRD), Fourier transform infrared spectroscopy, Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Thermal gravity-differential thermal analysis and Nitrogen sorption/desorption. The resulting layered double hydroxides were composed of nanoplates with edge-to-face particle interactions. The specific surface area and total pore volume of the as-prepared flower-like layered double hydroxides were 160m2/g and 0.65m3/g, respectively. The adsorption capacity of flower-like layered double hydroxides to Congo Red was 258mg/g, which was higher than that of layered double hydroxides synthesized by the traditional method.

Drosophila vitelline membrane assembly: A critical role for an evolutionarily conserved cysteine in the “VM domain” of sV23

PubMed Central

Wu, T; Manogaran, A.L; Beauchamp, J.M.; Waring, G.L.

2010-01-01

The vitelline membrane (VM), the oocyte proximal layer of the Drosophila eggshell, contains four major proteins (VMPs) that possess a highly conserved “VM domain” which includes three precisely spaced, evolutionarily conserved, cysteines (CX7CX8C). Focusing on sV23, this study showed that the three cysteines are not functionally equivalent. While substitution mutations at the first (C123S) or third (C140S) cysteines were tolerated, females with a substitution at the second position (C131S) were sterile. Fractionation studies showed sV23 incorporates into a large disulfide linked network well after its secretion ceases, suggesting post-depositional mechanisms are in place to restrict disulfide bond formation until late oogenesis, when the oocyte no longer experiences large volume increases. Affinity chromatography utilizing histidine tagged sV23 alleles revealed small sV23 disulfide linked complexes during the early stages of eggshell formation that included other VMPs, namely sV17 and Vml. The early presence but late loss of these associations in an sV23 double cysteine mutant suggests reorganization of disulfide bonds may underlie the regulated growth of disulfide-linked networks in the vitelline membrane. Found within the context of a putative thioredoxin active site (CXXS) C131, the critical cysteine in sV23, may play an important enzymatic role in isomerizing intermolecular disulfide bonds during eggshell assembly. PMID:20832396

Separation and purification of thymopentin with molecular imprinting membrane by solid phase extraction disks.

PubMed

Wang, Chaoli; Hu, Xiaoling; Guan, Ping; Wu, Danfeng; Qian, Liwei; Li, Ji; Song, Renyuan

2015-01-01

The synthesis and performance of molecularly imprinted membranes (MIMs) as a solid phase extraction packing materials for the separation and purification of thymopentin from crude samples was described. In order to increase structural selectivity and imprinting efficiency, surface-initiated ATRP and ionic liquid (1-vinyl-3-ethyl acetate imidazolium chloride) were used to prepare molecularly imprinting membranes. The results demonstrated that solid phase extraction disks stuffed by MIMs with ionic liquids as functional monomer demonstrated high isolation and purification of performance to the thymopentin. The molecular recognition of thymopentin was analyzed by using molecular modeling software. Copyright © 2014 Elsevier B.V. All rights reserved.

Phosphorus removal from aqueous solution in parent and aluminum-modified eggshells: thermodynamics and kinetics, adsorption mechanism, and diffusion process.

PubMed

Guo, Ziyan; Li, Jiuhai; Guo, Zhaobing; Guo, Qingjun; Zhu, Bin

2017-06-01

Parent and aluminum-modified eggshells were prepared and characterized with X-ray diffraction, specific surface area measurements, infrared spectroscopy, zeta potential, and scanning electron microscope, respectively. Besides, phosphorus adsorptions in these two eggshells at different temperatures and solution pH were carried out to study adsorption thermodynamics and kinetics as well as the mechanisms of phosphorus adsorption and diffusion. The results indicated that high temperature was favorable for phosphorus adsorption in parent and aluminum-modified eggshells. Alkaline solution prompted phosphorus adsorption in parent eggshell, while the maximum adsorption amount was achievable at pH 4 in aluminum-modified eggshell. Adsorption isotherms of phosphorus in these eggshells could be well described by Langmuir and Freundlich models. Phosphorus adsorption amounts in aluminum-modified eggshell were markedly higher compared to those in parent eggshell. Adsorption heat indicated that phosphorus adsorption in parent eggshell was a typically physical adsorption process, while chemical adsorption mechanism of ion exchange between phosphorus and hydroxyl groups on the surface of eggshells was dominated in aluminum-modified eggshell. The time-resolved uptake curves showed phosphorus adsorption in aluminum-modified eggshell was significantly faster than that in parent eggshell. Moreover, there existed two clear steps in time-resolved uptake curves of phosphorus in parent eggshell. Based on pseudo-second order kinetic model and intraparticle diffusion model, we inferred more than one process affected phosphorus adsorption. The first process was the diffusion of phosphorus through water to external surface and the opening of pore channel in the eggshells, and the second process was mainly related to intraparticle diffusion.

Effect of tea polyphenols on production performance, egg quality, and hepatic antioxidant status of laying hens in vanadium-containing diets.

PubMed

Yuan, Z H; Zhang, K Y; Ding, X M; Luo, Y H; Bai, S P; Zeng, Q F; Wang, J P

2016-07-01

This study was conducted to determine the effect of tea polyphenols (TP) on production performance, egg quality, and hepatic-antioxidant status of laying hens in vanadium-containing diets. A total of 300 Lohman laying hens (67 wk old) were used in a 1 plus 3 × 3 experiment design in which hens were given either a diet without vanadium and TP supplementation (control) or diets supplemented with 5, 10, or 15 mg V/kg and TP (0, 600, 1,000 mg/kg) diets for 8 wk, which included 2 phases: a 5-wk accumulation phase and a 3-wk depletion phase. During the accumulation phase, dietary vanadium addition decreased (linear, P < 0.01) albumen height and Haugh unit (HU), and TP supplementation mitigated (linear effect, P < 0.01) this reduction effect induced by vanadium. Eggshell thickness (linear, P < 0.01), redness (linear and quadratic, P < 0.05), and yellowness (linear and quadratic, P < 0.05) were decreased by vanadium and increased by the effect of TP when a vanadium-containing diet was fed. In the depletion phase, the bleaching effect on eggshells induced by vanadium disappeared one wk after vanadium withdrawal. Eggshell thickness, eggshell strength, albumen height, and HU were lower (P < 0.05) in the 15 mg/kg vanadium group compared with the control diet until 2 wk post vanadium challenge, but hens fed 15 mg/kg vanadium and 600 mg/kg TP showed no difference from the control diet only after 1 wk withdrawal. In the liver, the activity of glutathione S-transferases and glutathione peroxidase was increased (linear, P < 0.01) with the TP addition at 5 wk in the accumulation phase in the vanadium-containing diet; the malondialdehyde content increased (linear effect, P = 0.02) with the addition of vanadium. The results indicate that supplementation of 10 and 15 mg/kg vanadium resulted in reduced albumen quality, bleaching effect on eggshell color, and antioxidant stress in the liver. The effect of TP addition can prevent laying hens from the adverse effect of vanadium on egg quality, liver antioxidant stress and shorten the recovery time. © 2016 Poultry Science Association Inc.

Multiplexed Colorimetric Solid-Phase Extraction

NASA Technical Reports Server (NTRS)

Gazda, Daniel B.; Fritz, James S.; Porter, Marc D.

2009-01-01

Multiplexed colorimetric solid-phase extraction (MC-SPE) is an extension of colorimetric solid-phase extraction (C-SPE) an analytical platform that combines colorimetric reagents, solid phase extraction, and diffuse reflectance spectroscopy to quantify trace analytes in water. In CSPE, analytes are extracted and complexed on the surface of an extraction membrane impregnated with a colorimetric reagent. The analytes are then quantified directly on the membrane surface using a handheld diffuse reflectance spectrophotometer. Importantly, the use of solid-phase extraction membranes as the matrix for impregnation of the colorimetric reagents creates a concentration factor that enables the detection of low concentrations of analytes in small sample volumes. In extending C-SPE to a multiplexed format, a filter holder that incorporates discrete analysis channels and a jig that facilitates the concurrent operation of multiple sample syringes have been designed, enabling the simultaneous determination of multiple analytes. Separate, single analyte membranes, placed in a readout cartridge create unique, analyte-specific addresses at the exit of each channel. Following sample exposure, the diffuse reflectance spectrum of each address is collected serially and the Kubelka-Munk function is used to quantify each water quality parameter via calibration curves. In a demonstration, MC-SPE was used to measure the pH of a sample and quantitate Ag(I) and Ni(II).

Demulsification of water/oil/solid emulsions by hollow-fiber membranes

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

Tirmizi, N.P.; Raghuraman, B.; Wiencek, J.

1996-05-01

The demulsification techniques investigated use preferential surface wetting to allow separation of oil and water phases in ultrafiltration and microfiltration membranes. A hydrophobic membrane allows the permeation of an oil phase at almost zero pressure and retains the water phase, even though the molecular weight of the water molecule (18) is much smaller than that of the oil molecule (198 for tetradecane, used in this study). Hydrophobic membranes having pore sizes from 0.02 to 0.2 {micro}m were tested for demulsification of water-in-oil emulsions and water/oil/solid mixtures. The dispersed (aqueous)-phase drop sizes ranged from 1 to 5 {micro}m. High separation rates,more » as well as good permeate quality, were obtained with microfiltration membranes. Water content of permeating oil was 32--830 ppm depending on operating conditions and interfacial properties. For emulsions with high surfactant content, simultaneous operation of a hydrophobic and hydrophilic membrane, or simultaneous membrane separation with electric demulsification was more efficient in obtaining complete phase separation.« less

Maternal control of the Drosophila dorsal–ventral body axis

PubMed Central

Stein, David S.; Stevens, Leslie M.

2016-01-01

The pathway that generates the dorsal–ventral (DV) axis of the Drosophila embryo has been the subject of intense investigation over the previous three decades. The initial asymmetric signal originates during oogenesis by the movement of the oocyte nucleus to an anterior corner of the oocyte, which establishes DV polarity within the follicle through signaling between Gurken, the Drosophila Transforming Growth Factor (TGF)-α homologue secreted from the oocyte, and the Drosophila Epidermal Growth Factor Receptor (EGFR) that is expressed by the follicular epithelium cells that envelop the oocyte. Follicle cells that are not exposed to Gurken follow a ventral fate and express Pipe, a sulfotransferase that enzymatically modifies components of the inner vitelline membrane layer of the eggshell, thereby transferring DV spatial information from the follicle to the egg. These ventrally sulfated eggshell proteins comprise a localized cue that directs the ventrally restricted formation of the active Spätzle ligand within the perivitelline space between the eggshell and the embryonic membrane. Spätzle activates Toll, a transmembrane receptor in the embryonic membrane. Transmission of the Toll signal into the embryo leads to the formation of a ventral-to-dorsal gradient of the transcription factor Dorsal within the nuclei of the syncytial blastoderm stage embryo. Dorsal controls the spatially specific expression of a large constellation of zygotic target genes, the Dorsal gene regulatory network, along the embryonic DV circumference. This article reviews classic studies and integrates them with the details of more recent work that has advanced our understanding of the complex pathway that establishes Drosophila embryo DV polarity. PMID:25124754

Neutron Reflectivity as a Tool for Physics-Based Studies of Model Bacterial Membranes.

PubMed

Barker, Robert D; McKinley, Laura E; Titmuss, Simon

2016-01-01

The principles of neutron reflectivity and its application as a tool to provide structural information at the (sub-) molecular unit length scale from models for bacterial membranes are described. The model membranes can take the form of a monolayer for a single leaflet spread at the air/water interface, or bilayers of increasing complexity at the solid/liquid interface. Solid-supported bilayers constrain the bilayer to 2D but can be used to characterize interactions with antimicrobial peptides and benchmark high throughput lab-based techniques. Floating bilayers allow for membrane fluctuations, making the phase behaviour more representative of native membranes. Bilayers of varying levels of compositional accuracy can now be constructed, facilitating studies with aims that range from characterizing the fundamental physical interactions, through to the characterization of accurate mimetics for the inner and outer membranes of Gram-negative bacteria. Studies of the interactions of antimicrobial peptides with monolayer and bilayer models for the inner and outer membranes have revealed information about the molecular control of the outer membrane permeability, and the mode of interaction of antimicrobials with both inner and outer membranes.

Differential label-free quantitative proteomic analysis of avian eggshell matrix and uterine fluid proteins associated with eggshell mechanical property.

PubMed

Sun, Congjiao; Xu, Guiyun; Yang, Ning

2013-12-01

Eggshell strength is a crucial economic trait for table egg production. During the process of eggshell formation, uncalcified eggs are bathed in uterine fluid that plays regulatory roles in eggshell calcification. In this study, a label-free MS-based protein quantification technology was used to detect differences in protein abundance between eggshell matrix from strong and weak eggs (shell matrix protein from strong eggshells and shell matrix protein from weak eggshells) and between the corresponding uterine fluids bathing strong and weak eggs (uterine fluid bathing strong eggs and uterine fluid bathing weak eggs) in a chicken population. Here, we reported the first global proteomic analysis of uterine fluid. A total of 577 and 466 proteins were identified in uterine fluid and eggshell matrix, respectively. Of 447 identified proteins in uterine fluid bathing strong eggs, up to 357 (80%) proteins were in common with proteins in uterine fluid bathing weak eggs. Similarly, up to 83% (328/396) of the proteins in shell matrix protein from strong eggshells were in common with the proteins in shell matrix protein from weak eggshells. The large amount of common proteins indicated that the difference in protein abundance should play essential roles in influencing eggshell strength. Ultimately, 15 proteins mainly relating to eggshell matrix specific proteins, calcium binding and transportation, protein folding and sorting, bone development or diseases, and thyroid hormone activity were considered to have closer association with the formation of strong eggshell. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Irregularly calcified eggs and eggshells of Caiman latirostris (Alligatoridae: Crocodylia).

PubMed

Fernández, Mariela Soledad; Simoncini, Melina Soledad; Dyke, Gareth

2013-05-01

We describe irregularly calcified egg and eggshell morphologies for the first time in nests of the broad-snouted caiman, Caiman latirostris. Research is based on detailed descriptions of 270 eggs from a total sample of 46,800 collected between 2005 and 2011 in Santa Fe Province, Argentina, and encompasses animals from both natural habitats and held in captivity. We discuss possible reasons for the occurrence of eggs with different mineralisation patterns in our extensive C. latirostris field sample and its conservation significance; the chemistry of egg laying in amniotes is sensitive to environmental contamination which, in turn, has biological implications. Based on our egg sample, we identify two caiman eggshell abnormalities: (1) regularly calcified eggs with either calcitic nodules or superficial wrinkles at one egg end and (2) irregularly calcified eggs with structural gaps that weaken the shell. Some recently laid clutches we examined included eggs with most of the shell broken and detached from the flexible membrane. Most type 1 regularly calcified eggs lost their initial calcified nodules during incubation, suggesting that these deposits do not affect embryo survival rates. In contrast, irregularly calcified caiman eggs have a mean hatching success rate of 8.9% (range 0-38%) across our sample compared to a mean normal success of 75%. Most irregularly calcified caiman eggs probably die because of infections caused by fungi and bacteria in the organic nest material, although another possible explanation that merits further investigation could be an increase in permeability, leading to embryo dehydration.

Irregularly calcified eggs and eggshells of Caiman latirostris (Alligatoridae: Crocodylia)

NASA Astrophysics Data System (ADS)

Fernández, Mariela Soledad; Simoncini, Melina Soledad; Dyke, Gareth

2013-05-01

We describe irregularly calcified egg and eggshell morphologies for the first time in nests of the broad-snouted caiman, Caiman latirostris. Research is based on detailed descriptions of 270 eggs from a total sample of 46,800 collected between 2005 and 2011 in Santa Fe Province, Argentina, and encompasses animals from both natural habitats and held in captivity. We discuss possible reasons for the occurrence of eggs with different mineralisation patterns in our extensive C. latirostris field sample and its conservation significance; the chemistry of egg laying in amniotes is sensitive to environmental contamination which, in turn, has biological implications. Based on our egg sample, we identify two caiman eggshell abnormalities: (1) regularly calcified eggs with either calcitic nodules or superficial wrinkles at one egg end and (2) irregularly calcified eggs with structural gaps that weaken the shell. Some recently laid clutches we examined included eggs with most of the shell broken and detached from the flexible membrane. Most type 1 regularly calcified eggs lost their initial calcified nodules during incubation, suggesting that these deposits do not affect embryo survival rates. In contrast, irregularly calcified caiman eggs have a mean hatching success rate of 8.9 % (range 0-38 %) across our sample compared to a mean normal success of 75 %. Most irregularly calcified caiman eggs probably die because of infections caused by fungi and bacteria in the organic nest material, although another possible explanation that merits further investigation could be an increase in permeability, leading to embryo dehydration.

Solid-phase assays for small molecule screening using sol-gel entrapped proteins.

PubMed

Lebert, Julie M; Forsberg, Erica M; Brennan, John D

2008-04-01

With compound libraries exceeding one million compounds, the ability to quickly and effectively screen these compounds against relevant pharmaceutical targets has become crucial. Solid-phase assays present several advantages over solution-based methods. For example, a higher degree of miniaturization can be achieved, functional- and affinity-based studies are possible, and a variety of detection methods can be used. Unfortunately, most protein immobilization methods are either too harsh or require recombinant proteins and thus are not amenable to delicate proteins such as kinases and membrane-bound receptors. Sol-gel encapsulation of proteins in an inorganic silica matrix has emerged as a novel solid-phase assay platform. In this minireview, we discuss the development of sol-gel derived protein microarrays and sol-gel based monolithic bioaffinity columns for the high-throughput screening of small molecule libraries and mixtures.

Polyacrylate microspheres composite for all-solid-state reference electrodes.

PubMed

Kisiel, Anna; Donten, Mikołaj; Mieczkowski, Józef; Rius-Ruiz, F Xavier; Maksymiuk, Krzysztof; Michalska, Agata

2010-09-01

A novel concept is proposed for the encapsulation of components within polyacrylate microspheres, prior to their incorporation into a membrane phase. Thus finer and better controlled dispersion of heterogeneous membrane components can be achieved. This concept was verified by using a poly(n-butyl acrylate) membrane-based reference electrode as an example. In this example the proper dispersion of solid constituents of the heterogeneous membrane and prevention of their leakage are both of primary importance. Potassium chloride-loaded poly(n-butyl acrylate) microspheres were prepared and then left in contact with silver nitrate to convert some of the KCl into AgCl. The material obtained was introduced into a poly(n-butyl acrylate) membrane. The reference electrode membranes obtained in this way were characterized with much more stable potential (both in different electrolytes and over time) compared with electrodes prepared by the direct introduction of KCl and AgCl to the membrane.

Changes in pigment, spectral transmission and element content of pink chicken eggshells with different pigment intensity during incubation.

PubMed

Yu, Yue; Li, Zhanming; Pan, Jinming

2016-01-01

Objective. The objective of this study was to investigate changes in pigment, spectral transmission and element content of chicken eggshells with different intensities of pink pigment during the incubation period. We also investigated the effects of the region (small pole, equator and large pole) and pink pigment intensity of the chicken eggshell on the percent transmission of light passing through the chicken eggshells. Method. Eggs of comparable weight from a meat-type breeder (Meihuang) were used, and divided based on three levels of pink pigment (light, medium and dark) in the eggshells. During the incubation (0-21 d), the values of the eggshell pigment (ΔE, L (∗), a (∗), b (∗)) were measured. The percent transmission of light for different regions and intensities of eggshell pigmentation was measured by using the visible wavelength range of 380-780 nm. Result. Three measured indicators of eggshell color, ΔE, L (∗) and a (∗), did not change significantly during incubation. Compared with other regions and pigment intensities, eggshell at the small pole and with light pigmentation intensity showed the highest percent transmission of light. The transmission value varied significantly (P < 0.001) with incubation time. The element analysis of eggshells with different levels of pink pigment showed that the potassium content of the eggshells for all pigment levels decreased significantly during incubation. Conclusion. In summary, pigment intensity and the region of the eggshell influenced the percent transmission of light of eggshell. Differences in the spectral characteristics of different eggshells may influence the effects of photostimulation during the incubation of eggs. All of these results will be applicable for perfecting the design of light intensity for lighted incubation to improve productivity.

Changes in pigment, spectral transmission and element content of pink chicken eggshells with different pigment intensity during incubation

PubMed Central

Yu, Yue; Li, Zhanming

2016-01-01

Objective. The objective of this study was to investigate changes in pigment, spectral transmission and element content of chicken eggshells with different intensities of pink pigment during the incubation period. We also investigated the effects of the region (small pole, equator and large pole) and pink pigment intensity of the chicken eggshell on the percent transmission of light passing through the chicken eggshells. Method. Eggs of comparable weight from a meat-type breeder (Meihuang) were used, and divided based on three levels of pink pigment (light, medium and dark) in the eggshells. During the incubation (0–21 d), the values of the eggshell pigment (ΔE, L∗, a∗, b∗) were measured. The percent transmission of light for different regions and intensities of eggshell pigmentation was measured by using the visible wavelength range of 380–780 nm. Result. Three measured indicators of eggshell color, ΔE, L∗ and a∗, did not change significantly during incubation. Compared with other regions and pigment intensities, eggshell at the small pole and with light pigmentation intensity showed the highest percent transmission of light. The transmission value varied significantly (P < 0.001) with incubation time. The element analysis of eggshells with different levels of pink pigment showed that the potassium content of the eggshells for all pigment levels decreased significantly during incubation. Conclusion. In summary, pigment intensity and the region of the eggshell influenced the percent transmission of light of eggshell. Differences in the spectral characteristics of different eggshells may influence the effects of photostimulation during the incubation of eggs. All of these results will be applicable for perfecting the design of light intensity for lighted incubation to improve productivity. PMID:27019785

Thermoluminescence properties of CaO powder obtained from chicken eggshells

NASA Astrophysics Data System (ADS)

Nagabhushana, K. R.; Lokesha, H. S.; Satyanarayana Reddy, S.; Prakash, D.; Veerabhadraswamy, M.; Bhagyalakshmi, H.; Jayaramaiah, J. R.

2017-09-01

Eggshell wastage has created serious problem in disposal of the food processing industry which has been triggered the thoughts of researchers to use wasted eggshells as good source of calcium. In the present work, calcium oxide (CaO) has been synthesized by combustion process in furnace (F-CaO) and microwave oven (M-CaO) using the source of chicken eggshells. The obtained F-CaO and M-CaO are characterized by XRD, SEM with EDX and thermoluminescence (TL) technique. XRD pattern of both the samples show cubic phase with crystallite size 45-52 nm. TL glow curves are recorded for various gamma radiation dose (300-4000 Gy). Two TL glows, a small peak at 424 K and stronger peak at 597 K are observed. TL response of M-CaO is 2.67 times higher than F-CaO sample. TL kinetic parameters are calculated by computerized curve deconvolution analysis (CCDA) and discussed.

Solid-phase receptor binding assay for /sup 125/I-hCG

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

Bortolussi, M.; Selmin, O.; Colombatti, A.

1987-01-01

A solid-phase radioligand-receptor assay (RRA) to measure the binding of /sup 125/I-labelled human chorionic gonadotropin (/sup 125/I-hCG) to target cell membranes has been developed. The binding of /sup 125/I-hCG to membranes immobilized on the wells of microtitration plates reached a maximum at about 3 hours at 37 degrees C, was saturable, displayed a high affinity (Ka = 2.4 X 10(9) M-1) and was specifically inhibited by unlabelled hCG. In comparison with RRAs carried out with membranes in suspension, the solid-phase RRA is significantly simpler and much faster to perform as it avoids centrifugation or filtration procedures. The solid-phase RRA wasmore » adapted profitably to process large numbers of samples at the same time. It proved particularly useful as a screening assay to detect anti-hCG monoclonal antibodies with high inhibitory activity for binding of /sup 125/I-hCG to its receptors.« less

Effect of dope solution temperature on the membrane structure and membrane distillation performance

NASA Astrophysics Data System (ADS)

Nawi, N. I. M.; Bilad, M. R.; Nordin, N. A. H. M.

2018-04-01

Membrane distillation (MD) is a non-isothermal process applicable to purify water using hydrophobic membrane. Membrane in MD is hydrophobic, permeable to water vapor but repels liquid water. MD membrane is expected to pose high flux, high fouling and scaling resistances and most importantly high wetting resistance. This study develops flat-sheet polyvinylidene fluoride (PVDF) membrane by exploring both liquid-liquid and liquid-solid phase inversion technique largely to improve its wetting resistance and flux performance. We hypothesize that temperature of dope solution play roles in solid-liquid separation during membrane formation and an optimum balance between liquid-liquid and liquid-solid (crystallization) separation leads to highly performance PVDF membrane. Findings obtained from differential scanning calorimeter test show that increasing dope solution temperature reduces degree of PVDF crystallinity and suppresses formation of crystalline structure. The morphological images of the resulting membranes show that at elevated dope solution temperature (40, 60, 80 and 100°C), the spherulite-like structures are formed across the thickness of membranes ascribed from due to different type of crystals. The performance of direct-contact MD shows that the obtained flux of the optimum dope temperature (60°C) of 10.8 L/m2h is comparable to commercial PTFE-based MD membrane.

Fire propagation performance of intumescent fire protective coatings using eggshells as a novel biofiller.

PubMed

Yew, M C; Ramli Sulong, N H; Yew, M K; Amalina, M A; Johan, M R

2014-01-01

This paper aims to synthesize and characterize an effective intumescent fire protective coating that incorporates eggshell powder as a novel biofiller. The performances of thermal stability, char formation, fire propagation, water resistance, and adhesion strength of coatings have been evaluated. A few intumescent flame-retardant coatings based on these three ecofriendly fire retardant additives ammonium polyphosphate phase II, pentaerythritol and melamine mixed together with flame-retardant fillers, and acrylic binder have been prepared and designed for steel. The fire performance of the coatings has conducted employing BS 476: Part 6-Fire propagation test. The foam structures of the intumescent coatings have been observed using field emission scanning electron microscopy. On exposure, the coated specimens' B, C, and D had been certified to be Class 0 due to the fact that their fire propagation indexes were less than 12. Incorporation of ecofriendly eggshell, biofiller into formulation D led to excellent performance in fire stopping (index value, (I) = 4.3) and antioxidation of intumescent coating. The coating is also found to be quite effective in water repellency, uniform foam structure, and adhesion strength.

Fire Propagation Performance of Intumescent Fire Protective Coatings Using Eggshells as a Novel Biofiller

PubMed Central

Yew, M. C.; Ramli Sulong, N. H.; Yew, M. K.; Amalina, M. A.; Johan, M. R.

2014-01-01

This paper aims to synthesize and characterize an effective intumescent fire protective coating that incorporates eggshell powder as a novel biofiller. The performances of thermal stability, char formation, fire propagation, water resistance, and adhesion strength of coatings have been evaluated. A few intumescent flame-retardant coatings based on these three ecofriendly fire retardant additives ammonium polyphosphate phase II, pentaerythritol and melamine mixed together with flame-retardant fillers, and acrylic binder have been prepared and designed for steel. The fire performance of the coatings has conducted employing BS 476: Part 6-Fire propagation test. The foam structures of the intumescent coatings have been observed using field emission scanning electron microscopy. On exposure, the coated specimens' B, C, and D had been certified to be Class 0 due to the fact that their fire propagation indexes were less than 12. Incorporation of ecofriendly eggshell, biofiller into formulation D led to excellent performance in fire stopping (index value, (I) = 4.3) and antioxidation of intumescent coating. The coating is also found to be quite effective in water repellency, uniform foam structure, and adhesion strength. PMID:25136687

The eggshell of the cherry fly Rhagoletis cerasi.

PubMed

Mouzaki, D G; Margaritis, L H

1991-01-01

One of the major pests in Greek cherry orchards is the cherry fly Rhagoletis cerasi (Diptera: Tephritidae). In order to complete our comparative work on the chorion assembly of other representatives of the fruit flies (e.g. Ceratitis capitata and Dacus oleae) we studied eggshell morphogenesis in the cherry fly. The oocyte is surrounded by several distinct layers which are produced during choriogenesis. The eggshell consists of the vitelline membrane, a fibrous layer of possible water-proofing function, an innermost chorionic layer, endochorionic and exochorionic layers. The endochorion shows a branched configuration with irregular cavities, and the exochorion consists of inner and outer layers for better embryo protection. At the anterior region of the follicle, the hexagonal borders of the follicle cells are created by endochorionic material, covered by both inner and outer exochorion. This area resembles the D. melanogaster chorionic appendages and therefore can serve for plastron respiration. The structural results support the phylogenetic relationships among the tephritids (Rhagoletis is closer to Ceratitis than Dacus). The presence of peroxidase in the endochorion, detected by diaminobenzidine, is consistent with the eggshell hardening at the end of choriogenesis, following the same pattern with the other fruit flies studied so far. Two major chorionic proteins are found both in R. cerasi and in C. capitata and therefore general conclusions can be drawn from this study, concerning the pattern of choriogenesis, which all dipteran insects follow, in order to create a resistant and functional eggshell, and the high conservation of the proteinaceous components of the chorion among species in the order.

Mechanical Properties of Composite Waste Material Based Styrofoam, Baggase and Eggshell Powder for Application of Drone Frames

NASA Astrophysics Data System (ADS)

Perdana, Mastariyanto; Prastiawan; Hadi, Syafrul

2017-12-01

The garbage issue becomes a very serious problem at the moment. Much research has been done to make waste into useful materials. One of the utilization of waste is as the basic material of composite material that can be applied in the field of engineering. Some of the wastes generated are styrofoam, bagasse and eggshell. Styrofoam, bagasse and eggshell can be applied to a composite material. Styrofoam serves as a composite binder material while the bagasse and eggshells serve as a reinforcement. Volume fraction between styrofoam, bagasse and eggshell are 80%:10%:10%, 70%:15%:15%, 60%:20%:20%, and 50%:25%:25%. The aims of research are determine the mechanical properties of composite material based waste materials from styrofoam, bagasse and eggshell. Mechanical properties tested in this study are bending strength and toughness of composite materials. The results showed bending strength of composite for each volume fraction of 80%:10%:10%, 70%:15%:15%, 60%:20%:20%, and 50%:25%:25% are 5.07 MPa, 8.45 MPa, 8.68 MPa, and 11.01 MPa, respectively. Toughness of composite materials for each volume fraction of 80%:10%:10%, 70%:15%:15%, 60%:20%:20%, and 50%:25%:25% are 0.33 J/mm2, 0.42 J/mm2, 0.75 J/mm2, and 0.75 J/mm2, respectively. Composite materials based on waste materials from styrofoam, bagasse and eggshell can be used as an alternative material for drone frames.

An EAV-HP Insertion in 5′ Flanking Region of SLCO1B3 Causes Blue Eggshell in the Chicken

PubMed Central

Yang, Xiaolin; Li, Guangqi; Zhang, Yuanyuan; Li, Junying; Wang, Xiaotong; Bai, Jirong; Xu, Guiyun; Deng, Xuemei; Yang, Ning; Wu, Changxin

2013-01-01

The genetic determination of eggshell coloration has not been determined in birds. Here we report that the blue eggshell is caused by an EAV-HP insertion that promotes the expression of SLCO1B3 gene in the uterus (shell gland) of the oviduct in chicken. In this study, the genetic map location of the blue eggshell gene was refined by linkage analysis in an F2 chicken population, and four candidate genes within the refined interval were subsequently tested for their expression levels in the shell gland of the uterus from blue-shelled and non-blue-shelled hens. SLCO1B3 gene was found to be the only one expressed in the uterus of blue-shelled hens but not in that of non-blue-shelled hens. Results from a pyrosequencing analysis showed that only the allele of SLCO1B3 from blue-shelled chickens was expressed in the uterus of heterozygous hens (O*LC/O*N). SLCO1B3 gene belongs to the organic anion transporting polypeptide (OATP) family; and the OATPs, functioning as membrane transporters, have been reported for the transportation of amphipathic organic compounds, including bile salt in mammals. We subsequently resequenced the whole genomic region of SLCO1B3 and discovered an EAV-HP insertion in the 5′ flanking region of SLCO1B3. The EAV-HP insertion was found closely associated with blue eggshell phenotype following complete Mendelian segregation. In situ hybridization also demonstrated that the blue eggshell is associated with ectopic expression of SLCO1B3 in shell glands of uterus. Our finding strongly suggests that the EAV-HP insertion is the causative mutation for the blue eggshell phenotype. The insertion was also found in another Chinese blue-shelled breed and an American blue-shelled breed. In addition, we found that the insertion site in the blue-shelled chickens from Araucana is different from that in Chinese breeds, which implied independent integration events in the blue-shelled chickens from the two continents, providing a parallel evolutionary example at the molecular level. PMID:23359636

Co-composting of eggshell waste in self-heating reactors: monitoring and end product quality.

PubMed

Soares, Micaela A R; Quina, Margarida M J; Quinta-Ferreira, Rosa M

2013-11-01

Industrial eggshell waste (ES) is classified as an animal by-product not intended to human consumption. For reducing pathogen spreading risk due to soil incorporation of ES, sanitation by composting is a pre-treatment option. This work aims to evaluate eggshell waste recycling in self-heating composting reactors and investigate ES effect on process evolution and end product quality. Potato peel, grass clippings and rice husks were the starting organic materials considered. The incorporation of 30% (w/w) ES in a composting mixture did not affect mixture biodegradability, nor its capacity to reach sanitizing temperatures. After 25 days of composting, ES addition caused a nitrogen loss of about 10 g N kg(-1) of initial volatile solids, thus reducing nitrogen nutritional potential of the finished compost. This study showed that a composting mixture with a significant proportion of ES (30% w/w) may be converted into calcium-rich marketable compost to neutralize soil acidity and/or calcium deficiencies. Copyright © 2013 Elsevier Ltd. All rights reserved.

Solid-phase extraction and purification of membrane proteins using a UV-modified PMMA microfluidic bioaffinity μSPE device.

PubMed

Battle, Katrina N; Jackson, Joshua M; Witek, Małgorzata A; Hupert, Mateusz L; Hunsucker, Sally A; Armistead, Paul M; Soper, Steven A

2014-03-21

We present a novel microfluidic solid-phase extraction (μSPE) device for the affinity enrichment of biotinylated membrane proteins from whole cell lysates. The device offers features that address challenges currently associated with the extraction and purification of membrane proteins from whole cell lysates, including the ability to release the enriched membrane protein fraction from the extraction surface so that they are available for downstream processing. The extraction bed was fabricated in PMMA using hot embossing and was comprised of 3600 micropillars. Activation of the PMMA micropillars by UV/O3 treatment permitted generation of surface-confined carboxylic acid groups and the covalent attachment of NeutrAvidin onto the μSPE device surfaces, which was used to affinity select biotinylated MCF-7 membrane proteins directly from whole cell lysates. The inclusion of a disulfide linker within the biotin moiety permitted release of the isolated membrane proteins via DTT incubation. Very low levels (∼20 fmol) of membrane proteins could be isolated and recovered with ∼89% efficiency with a bed capacity of 1.7 pmol. Western blotting indicated no traces of cytosolic proteins in the membrane protein fraction as compared to significant contamination using a commercial detergent-based method. We highlight future avenues for enhanced extraction efficiency and increased dynamic range of the μSPE device using computational simulations of different micropillar geometries to guide future device designs.

Polyvinylidene Fluoride Micropore Membranes as Solid-Phase Extraction Disk for Preconcentration of Nanoparticulate Silver in Environmental Waters.

PubMed

Zhou, Xiao-Xia; Lai, Yu-Jian; Liu, Rui; Li, Sha-Sha; Xu, Jing-Wen; Liu, Jing-Fu

2017-12-05

Efficient separation and preconcentration of trace nanoparticulate silver (NAg) from large-volume environmental waters is a prerequisite for reliable analysis and therefore understanding the environmental processes of silver nanoparticles (AgNPs). Herein, we report the novel use of polyvinylidene fluoride (PVDF) filter membrane for disk-based solid phase extraction (SPE) of NAg in 1 L of water samples with the disk-based SPE system, which consists of a syringe pump and a syringe filter holder to embed the filter membrane. While the PVDF membrane can selectively adsorb NAg in the presence of Ag + , aqueous solution of 2% (m/v) FL-70 is found to efficiently elute NAg. Analysis of NAg is performed following optimization of filter membrane and elution conditions with an enrichment factor of 1000. Additionally, transmission electron microscopy (TEM), UV-vis spectroscopy, and size-exclusion chromatography coupled with ICP-MS (SEC-ICP-MS) analysis showed that the extraction gives rise to no change in NAg size or shape, making this method attractive for practical applications. Furthermore, feasibility of the protocol is verified by applying it to extract NAg in four real waters with recoveries of 62.2-80.2% at 0.056-0.58 μg/L spiked levels. This work will facilitate robust studies of trace NAg transformation and their hazard assessments in the environment.

Solid phase microbial fuel cell (SMFC) for harnessing bioelectricity from composite food waste fermentation: influence of electrode assembly and buffering capacity.

PubMed

Mohan, S Venkata; Chandrasekhar, K

2011-07-01

Solid phase microbial fuel cells (SMFC; graphite electrodes; open-air cathode) were designed to evaluate the potential of bioelectricity production by stabilizing composite canteen based food waste. The performance was evaluated with three variable electrode-membrane assemblies. Experimental data depicted feasibility of bioelectricity generation from solid state fermentation of food waste. Distance between the electrodes and presence of proton exchange membrane (PEM) showed significant influence on the power yields. SMFC-B (anode placed 5 cm from cathode-PEM) depicted good power output (463 mV; 170.81 mW/m(2)) followed by SMFC-C (anode placed 5 cm from cathode; without PEM; 398 mV; 53.41 mW/m(2)). SMFC-A (PEM sandwiched between electrodes) recorded lowest performance (258 mV; 41.8 mW/m(2)). Sodium carbonate amendment documented marked improvement in power yields due to improvement in the system buffering capacity. SMFCs operation also documented good substrate degradation (COD, 76%) along with bio-ethanol production. The operation of SMFC mimicked solid-sate fermentation which might lead to sustainable solid waste management practices. Copyright © 2011 Elsevier Ltd. All rights reserved.

Protein profiles of hatchery egg shell membrane.

PubMed

Rath, N C; Liyanage, R; Makkar, S K; Lay, J O

2016-01-01

Eggshells which consist largely of calcareous outer shell and shell membranes, constitute a significant part of poultry hatchery waste. The shell membranes (ESM) not only contain proteins that originate from egg whites but also from the developing embryos and different contaminants of microbial and environmental origins. As feed supplements, during post hatch growth, the hatchery egg shell membranes (HESM) have shown potential for imparting resistance of chickens to endotoxin stress and exert positive health effects. Considering that these effects are mediated by the bioactive proteins and peptides present in the membrane, the objective of the study was to identify the protein profiles of hatchery eggshell membranes (HESM). Hatchery egg shell membranes were extracted with acidified methanol and a guanidine hydrochloride buffer then subjected to reduction/alkylation, and trypsin digestion. The methanol extract was additionally analyzed by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS). The tryptic digests were analyzed by liquid chromatography and tandem mass spectrometry (LC-MS-MS) to identify the proteins. Our results showed the presence of several proteins that are inherent and abundant in egg white such as, ovalbumin, ovotransferrin, ovocleidin-116, and lysozyme, and several proteins associated with cytoskeletal, cell signaling, antimicrobial, and catalytic functions involving carbohydrate, nucleic acid, and protein metabolisms. There were some blood derived proteins most likely originating from the embryos and several other proteins identified with different aerobic, anaerobic, gram positive, gram negative, soil, and marine bacterial species some commensals and others zoonotic. The variety of bioactive proteins, particularly the cell signaling and enzymatic proteins along with the diverse microbial proteins, make the HESM suitable for nutritional and biological application to improve post hatch immunity of poultry.

Fabrication of PVDF-based blend membrane with a thin hydrophilic deposition layer and a network structure supporting layer via the thermally induced phase separation followed by non-solvent induced phase separation process

NASA Astrophysics Data System (ADS)

Wu, Zhiguo; Cui, Zhenyu; Li, Tianyu; Qin, Shuhao; He, Benqiao; Han, Na; Li, Jianxin

2017-10-01

A simple strategy of thermally induced phase separation followed by non-solvent induced phase separation (TIPS-NIPS) is reported to fabricate poly (vinylidene fluoride) (PVDF)-based blend membrane. The dissolved poly (styrene-co-maleic anhydride) (SMA) in diluent prevents the crystallization of PVDF during the cooling process and deposites on the established PVDF matrix in the later extraction. Compared with traditional coating technique, this one-step TIPS-NIPS method can not only fabricate a supporting layer with an interconnected network structure even via solid-liquid phase separation of TIPS, but also form a uniform SMA skin layer approximately as thin as 200 nm via surface deposition of NIPS. Besides the better hydrophilicity, what's interesting is that the BSA rejection ratio increases from 48% to 94% with the increase of SMA, which indicates that the separation performance has improved. This strategy can be conveniently extended to the creation of firmly thin layer, surface functionalization and structure controllability of the membrane.

Eggshell Spottiness Reflects Maternally Transferred Antibodies in Blue Tits

PubMed Central

Holveck, Marie-Jeanne; Grégoire, Arnaud; Staszewski, Vincent; Guerreiro, Romain; Perret, Philippe; Boulinier, Thierry; Doutrelant, Claire

2012-01-01

Blue-green and brown-spotted eggshells in birds have been proposed as sexual signals of female physiological condition and egg quality, reflecting maternal investment in the egg. Testing this hypothesis requires linking eggshell coloration to egg content, which is lacking for brown protoporphyrin-based pigmentation. As protoporphyrins can induce oxidative stress, and a large amount in eggshells should indicate either high female and egg quality if it reflects the female's high oxidative tolerance, or conversely poor quality if it reflects female physiological stress. Different studies supported either predictions but are difficult to compare given the methodological differences in eggshell-spottiness measurements. Using the blue tit Cyanistes caeruleus as a model species, we aimed at disentangling both predictions in testing if brown-spotted eggshell could reflect the quality of maternal investment in antibodies and carotenoids in the egg, and at improving between-study comparisons in correlating several common measurements of eggshell coloration (spectral and digital measures, spotted surface, pigmentation indices). We found that these color variables were weakly correlated highlighting the need for comparable quantitative measurements between studies and for multivariate regressions incorporating several eggshell-color characteristics. When evaluating the potential signaling function of brown-spotted eggshells, we thus searched for the brown eggshell-color variables that best predicted the maternal transfer of antibodies and carotenoids to egg yolks. We also tested the effects of several parental traits and breeding parameters potentially affecting this transfer. While eggshell coloration did not relate to yolk carotenoids, the eggs with larger and less evenly-distributed spots had higher antibody concentrations, suggesting that both the quantity and distribution of brown pigments reflected the transfer of maternal immune compounds in egg yolks. As yolk antibody concentrations were also positively related to key proxies of maternal quality (egg volume, number, yellow feather brightness, tarsus length), eggshells with larger spots concentrated at their broad pole may indicate higher-quality eggs. PMID:23226272

Evolution and development of model membranes for physicochemical and functional studies of the membrane lateral heterogeneity.

PubMed

Morigaki, Kenichi; Tanimoto, Yasushi

2018-03-14

One of the main questions in the membrane biology is the functional roles of membrane heterogeneity and molecular localization. Although segregation and local enrichment of protein/lipid components (rafts) have been extensively studied, the presence and functions of such membrane domains still remain elusive. Along with biochemical, cell observation, and simulation studies, model membranes are emerging as an important tool for understanding the biological membrane, providing quantitative information on the physicochemical properties of membrane proteins and lipids. Segregation of fluid lipid bilayer into liquid-ordered (Lo) and liquid-disordered (Ld) phases has been studied as a simplified model of raft in model membranes, including giant unilamellar vesicles (GUVs), giant plasma membrane vesicles (GPMVs), and supported lipid bilayers (SLB). Partition coefficients of membrane proteins between Lo and Ld phases were measured to gauze their affinities to lipid rafts (raftophilicity). One important development in model membrane is patterned SLB based on the microfabrication technology. Patterned Lo/Ld phases have been applied to study the partition and function of membrane-bound molecules. Quantitative information of individual molecular species attained by model membranes is critical for elucidating the molecular functions in the complex web of molecular interactions. The present review gives a short account of the model membranes developed for studying the lateral heterogeneity, especially focusing on patterned model membranes on solid substrates. Copyright © 2018 Elsevier B.V. All rights reserved.

Data set for the proteomic inventory and quantitative analysis of chicken eggshell matrix proteins during the primary events of eggshell mineralization and the active growth phase of calcification.

PubMed

Marie, Pauline; Labas, Valérie; Brionne, Aurélien; Harichaux, Grégoire; Hennequet-Antier, Christelle; Rodriguez-Navarro, Alejandro B; Nys, Yves; Gautron, Joël

2015-09-01

Chicken eggshell is a biomineral composed of 95% calcite calcium carbonate mineral and of 3.5% organic matrix proteins. The assembly of mineral and its structural organization is controlled by its organic matrix. In a recent study [1], we have used quantitative proteomic, bioinformatic and functional analyses to explore the distribution of 216 eggshell matrix proteins at four key stages of shell mineralization defined as: (1) widespread deposition of amorphous calcium carbonate (ACC), (2) ACC transformation into crystalline calcite aggregates, (3) formation of larger calcite crystal units and (4) rapid growth of calcite as columnar structure with preferential crystal orientation. The current article detailed the quantitative analysis performed at the four stages of shell mineralization to determine the proteins which are the most abundant. Additionally, we reported the enriched GO terms and described the presence of 35 antimicrobial proteins equally distributed at all stages to keep the egg free of bacteria and of 81 proteins, the function of which could not be ascribed.

Data set for the proteomic inventory and quantitative analysis of chicken eggshell matrix proteins during the primary events of eggshell mineralization and the active growth phase of calcification

PubMed Central

Marie, Pauline; Labas, Valérie; Brionne, Aurélien; Harichaux, Grégoire; Hennequet-Antier, Christelle; Rodriguez-Navarro, Alejandro B.; Nys, Yves; Gautron, Joël

2015-01-01

Chicken eggshell is a biomineral composed of 95% calcite calcium carbonate mineral and of 3.5% organic matrix proteins. The assembly of mineral and its structural organization is controlled by its organic matrix. In a recent study [1], we have used quantitative proteomic, bioinformatic and functional analyses to explore the distribution of 216 eggshell matrix proteins at four key stages of shell mineralization defined as: (1) widespread deposition of amorphous calcium carbonate (ACC), (2) ACC transformation into crystalline calcite aggregates, (3) formation of larger calcite crystal units and (4) rapid growth of calcite as columnar structure with preferential crystal orientation. The current article detailed the quantitative analysis performed at the four stages of shell mineralization to determine the proteins which are the most abundant. Additionally, we reported the enriched GO terms and described the presence of 35 antimicrobial proteins equally distributed at all stages to keep the egg free of bacteria and of 81 proteins, the function of which could not be ascribed. PMID:26306314

Development of a Portable Test Kit for Field-Screening Paints

DTIC Science & Technology

1986-01-01

Use) rods. TT-P-002119 Paint, Latex Base, High Traffic Areas, Flat and Eggshell Finish Discussion (Low Lustre, For Interior Use) The applications...testing uniformity in different clean. Eggshell or flat surfaces have more pigment than laboratories. Although the methods are designed to vehicle on...samples (Table 12) were selected from the useful for determining the gloss of eggshell , semigloss, series to represent the range of gloss (glossy

Probing the role of ceramide hydroxylation in skin barrier lipid models by 2H solid-state NMR spectroscopy and X-ray powder diffraction.

PubMed

Kováčik, Andrej; Vogel, Alexander; Adler, Juliane; Pullmannová, Petra; Vávrová, Kateřina; Huster, Daniel

2018-05-01

In this work, we studied model stratum corneum lipid mixtures composed of the hydroxylated skin ceramides N-lignoceroyl 6-hydroxysphingosine (Cer[NH]) and α-hydroxylignoceroyl phytosphingosine (Cer[AP]). Two model skin lipid mixtures of the composition Cer[NH] or Cer[AP], N-lignoceroyl sphingosine (Cer[NS]), lignoceric acid (C24:0) and cholesterol in a 0.5:0.5:1:1 molar ratio were compared. Model membranes were investigated by differential scanning calorimetry and 2 H solid-state NMR spectroscopy at temperatures from 25 °C to 80 °C. Each component of the model mixture was specifically deuterated for selective detection by 2 H NMR. Thus, the exact phase composition of the mixture at varying temperatures could be quantified. Moreover, using X-ray powder diffraction we investigated the lamellar phase formation. From the solid-state NMR and DSC studies, we found that both hydroxylated Cer[NH] and Cer[AP] exhibit a similar phase behavior. At physiological skin temperature of 32 °C, the lipids form a crystalline (orthorhombic) phase. With increasing temperature, most of the lipids become fluid and form a liquid-crystalline phase, which converts to the isotropic phase at higher temperatures (65-80 °C). Interestingly, lignoceric acid in the Cer[NH]-containing mixture has a tendency to form two types of fluid phases at 65 °C. This tendency was also observed in Cer[AP]-containing membranes at 80 °C. While Cer[AP]-containing lipid models formed a short periodicity phase featuring a repeat spacing of d = 5.4 nm, in the Cer[NH]-based model skin lipid membranes, the formation of unusual long periodicity phase with a repeat spacing of d = 10.7 nm was observed. Copyright © 2018 Elsevier B.V. All rights reserved.

Large effect of membrane tension on the fluid-solid phase transitions of two-component phosphatidylcholine vesicles.

PubMed

Chen, Dong; Santore, Maria M

2014-01-07

Model phospholipid membranes and vesicles have long provided insight into the nature of confined materials and membranes while also providing a platform for drug delivery. The rich thermodynamic behavior and interesting domain shapes in these membranes have previously been mapped in extensive studies that vary temperature and composition; however, the thermodynamic impact of tension on bilayers has been restricted to recent reports of subtly reduced fluid-fluid transition temperatures. In two-component phosphatidylcholine unilamellar vesicles [1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)/1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)], we report a dramatic influence of tension on the fluid-solid transition and resulting phases: At fixed composition, systematic variations in tension produce differently shaped solid domains (striped or irregular hexagons), shift fluid-solid transition temperatures, and produce a triple-point-like intersection of coexistence curves at elevated tensions, about 3 mN/m for 30% DOPC/70% DPPC. Tension therefore represents a potential switch of microstructure in responsive engineered materials; it is an important morphology-determining variable in confined systems, and, in biological membranes, it may provide a means to regulate dynamic structure.

Nutritional Supplement of Hatchery Eggshell Membrane Improves Poultry Performance and Provides Resistance against Endotoxin Stress

PubMed Central

Makkar, S. K.; Rath, N. C.; Packialakshmi, B.; Zhou, Z. Y.; Huff, G. R.; Donoghue, A. M.

2016-01-01

Eggshells are significant part of hatchery waste which consist of calcium carbonate crust, membranes, and proteins and peptides of embryonic origins along with other entrapped contaminants including microbes. We hypothesized that using this product as a nutritional additive in poultry diet may confer better immunity to the chickens in the paradigm of mammalian milk that enhances immunity. Therefore, we investigated the effect of hatchery eggshell membranes (HESM) as a short term feed supplement on growth performance and immunity of chickens under bacterial lipopolysaccharide (LPS) challenged condition. Three studies were conducted to find the effect of HESM supplement on post hatch chickens. In the first study, the chickens were fed either a control diet or diets containing 0.5% whey protein or HESM as supplement and evaluated at 5 weeks of age using growth, hematology, clinical chemistry, plasma immunoglobulins, and corticosterone as variables. The second and third studies were done to compare the effects of LPS on control and HESM fed birds at 5 weeks of age following at 4 and 24 h of treatment where the HESM was also sterilized with ethanol to deplete bacterial factors. HESM supplement caused weight gain in 2 experiments and decreased blood corticosterone concentrations. While LPS caused a significant loss in body weight at 24 h following its administration, the HESM supplemented birds showed significantly less body weight loss compared with the control fed birds. The WBC, heterophil/lymphocyte ratio, and the levels of IgG were low in chickens fed diets with HESM supplement compared with control diet group. LPS challenge increased the expression of pro-inflammatory cytokine gene IL-6 but the HESM fed birds showed its effect curtailed, also, which also, favored the up-regulation of anti-inflammatory genes compared with control diet fed chickens. Post hatch supplementation of HESM appears to improve performance, modulate immunity, and increase resistance of chickens to endotoxin. PMID:27463239

Nutritional Supplement of Hatchery Eggshell Membrane Improves Poultry Performance and Provides Resistance against Endotoxin Stress.

PubMed

Makkar, S K; Rath, N C; Packialakshmi, B; Zhou, Z Y; Huff, G R; Donoghue, A M

2016-01-01

Eggshells are significant part of hatchery waste which consist of calcium carbonate crust, membranes, and proteins and peptides of embryonic origins along with other entrapped contaminants including microbes. We hypothesized that using this product as a nutritional additive in poultry diet may confer better immunity to the chickens in the paradigm of mammalian milk that enhances immunity. Therefore, we investigated the effect of hatchery eggshell membranes (HESM) as a short term feed supplement on growth performance and immunity of chickens under bacterial lipopolysaccharide (LPS) challenged condition. Three studies were conducted to find the effect of HESM supplement on post hatch chickens. In the first study, the chickens were fed either a control diet or diets containing 0.5% whey protein or HESM as supplement and evaluated at 5 weeks of age using growth, hematology, clinical chemistry, plasma immunoglobulins, and corticosterone as variables. The second and third studies were done to compare the effects of LPS on control and HESM fed birds at 5 weeks of age following at 4 and 24 h of treatment where the HESM was also sterilized with ethanol to deplete bacterial factors. HESM supplement caused weight gain in 2 experiments and decreased blood corticosterone concentrations. While LPS caused a significant loss in body weight at 24 h following its administration, the HESM supplemented birds showed significantly less body weight loss compared with the control fed birds. The WBC, heterophil/lymphocyte ratio, and the levels of IgG were low in chickens fed diets with HESM supplement compared with control diet group. LPS challenge increased the expression of pro-inflammatory cytokine gene IL-6 but the HESM fed birds showed its effect curtailed, also, which also, favored the up-regulation of anti-inflammatory genes compared with control diet fed chickens. Post hatch supplementation of HESM appears to improve performance, modulate immunity, and increase resistance of chickens to endotoxin.

Synthesis and characterization of eggshell-derived hydroxyapatite via mechanochemical method: A comparative study

NASA Astrophysics Data System (ADS)

Hamidi, A. A.; Salimi, M. N.; Yusoff, A. H. M.

2017-04-01

The focus of bone graft properties has developed through generations, from the ability to withstand mechanical stress to the ability to integrate with the biological structure. In recent years, the use of hydroxyapatite (HA) as bone graft material in orthopedic and dental applications has been increasing. HA is a natural occuring mineral with excellent bioactivity but relatively poor mechanical properties. It constitutes 96% portion of enamel in teeth and 67% portion of bone. HA can be extracted from animal bones or fabricated from synthetic or biologic sources. In this study, eggshells were used as raw material to synthesize eggshell-derived HA (EHA) via mechanochemical method. The synthesis of EHA involved CaO, which was obtained from the calcination of eggshells, and reaction with dicalcium hydrogen phosphate dihydrous (DCPD) or phosphoric acid (H3PO4). The effects of rotational speed and heat treatment temperature on EHA's characteristics were investigated. The characterization studies were carried out by using the Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) analysis and Scanning Electron Microscopy (SEM). HA powder was successfully synthesized with crystallite and particle sizes in the range of 8-47 nm and 250-550 nm respectively. It was observed from this study that the increase of milling rotational speed had increased the phase purity of EHA samples. Furthermore, the higher heating temperature of HA samples resulted in higher degree of crystallinity of HA and the appearance of β-tricalcium phosphate (β-TCP) as secondary phase.

Nanoporous separators for supercapacitor using activated carbon monolith electrode from oil palm empty fruit bunches

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

Nor, N. S. M., E-mail: madra@ukm.my; Deraman, M., E-mail: madra@ukm.my; Omar, R., E-mail: madra@ukm.my

Activated porous carbon electrode prepared from fibres of oil palm empty fruit bunches was used for preparing the carbon based supercapacitor cells. The symmetrical supercapacitor cells were fabricated using carbon electrodes, stainless steel current collector, H{sub 2}SO{sub 4} electrolyte, and three types of nanoporous separators. Cells A, B and C were fabricated using polypropylene, eggshell membrane, and filter paper, respectively. Electrochemical characterizations data from Electrochemical Impedance Spectroscopy, Cyclic Voltammetry, and Galvanic Charge Discharge techniques showed that specific capacitance, specific power and specific energy for cell A were 122 F g{sup −1}, 177 W kg{sup −1}, 3.42 Wh kg{sup −1}, cellmore » B; 125 F g{sup −1}, 179 W kg{sup −1}, and 3.64 Wh kg{sup −1}, and cell C; 180 F g{sup −1}, 178 W kg{sup −1}, 4.27 Wh kg{sup −1}. All the micrographs from Field Emission Scanning Electron Microscope showed that the different in nanoporous structure of the separators lead to a significant different in influencing the values of specific capacitance, power and energy of supercapacitors, which is associated with the mobility of ion into the pore network. These results indicated that the filter paper was superior than the eggshell membrane and polypropylene nanoporous separators. However, we found that in terms of acidic resistance, polypropylene was the best nanoporous separator for acidic medium.« less

Application of eggshell waste for the immobilization of cadmium and lead in a contaminated soil.

PubMed

Ok, Yong Sik; Lee, Sang Soo; Jeon, Weon-Tai; Oh, Sang-Eun; Usman, Adel R A; Moon, Deok Hyun

2011-01-01

Liming materials have been used to immobilize heavy metals in contaminated soils. However, no studies have evaluated the use of eggshell waste as a source of calcium carbonate (CaCO₃) to immobilize both cadmium (Cd) and lead (Pb) in soils. This study was conducted to evaluate the effectiveness of eggshell waste on the immobilization of Cd and Pb and to determine the metal availability following various single extraction techniques. Incubation experiments were conducted by mixing 0-5% powdered eggshell waste and curing the soil (1,246 mg Pb kg⁻¹ soil and 17 mg Cd kg⁻¹ soil) for 30 days. Five extractants, 0.01 M calcium chloride (CaCl₂), 1 M CaCl₂, 0.1 M hydrochloric acid (HCl), 0.43 M acetic acid (CH₃COOH), and 0.05 M ethylendiaminetetraacetic acid (EDTA), were used to determine the extractability of Cd and Pb following treatments with CaCO₃ and eggshell waste. Generally, the extractability of Cd and Pb in the soils decreased in response to treatments with CaCO₃ and eggshell waste, regardless of extractant. Using CaCl₂ extraction, the lowest Cd concentration was achieved upon both CaCO₃ and eggshell waste treatments, while the lowest Pb concentration was observed using HCl extraction. The highest amount of immobilized Cd and Pb was extracted by CH₃COOH or EDTA in soils treated with CaCO₃ and eggshell waste, indicating that remobilization of Cd and Pb may occur under acidic conditions. Based on the findings obtained, eggshell waste can be used as an alternative to CaCO₃ for the immobilization of heavy metals in soils.

Linking Findings in Microfluidics to Membrane Emulsification Process Design: The Importance of Wettability and Component Interactions with Interfaces

PubMed Central

Schroën, Karin; Ferrando, Montse; de Lamo-Castellví, Silvia; Sahin, Sami; Güell, Carme

2016-01-01

In microfluidics and other microstructured devices, wettability changes, as a result of component interactions with the solid wall, can have dramatic effects. In emulsion separation and emulsification applications, the desired behavior can even be completely lost. Wettability changes also occur in one phase systems, but the effect is much more far-reaching when using two-phase systems. For microfluidic emulsification devices, this can be elegantly demonstrated and quantified for EDGE (Edge-base Droplet GEneration) devices that have a specific behavior that allows us to distinguish between surfactant and liquid interactions with the solid surface. Based on these findings, design rules can be defined for emulsification with any micro-structured emulsification device, such as direct and premix membrane emulsification. In general, it can be concluded that mostly surface interactions increase the contact angle toward 90°, either through the surfactant, or the oil that is used. This leads to poor process stability, and very limited pressure ranges at which small droplets can be made in microfluidic systems, and cross-flow membrane emulsification. In a limited number of cases, surface interactions can also lead to lower contact angles, thereby increasing the operational stability. This paper concludes with a guideline that can be used to come to the appropriate combination of membrane construction material (or any micro-structured device), surfactants and liquids, in combination with process conditions. PMID:27187484

Carbonic anhydrases in chick extra-embryonic structures: a role for CA in bicarbonate reabsorption through the chorioallantoic membrane.

PubMed

Gabrielli, M Gabriella

2004-06-01

The villus cavity cells, a specific cell type of the chick chorioallantoic membrane, express both cytosolic carbonic anhydrase in their cytoplasm and HCO3(-)/Cl(-) anion exchangers at their basolateral membranes. By immunohistochemical analysis, we show here that villus cavity cells specifically react with antibodies directed against the membrane-associated form of carbonic anhydrase, CAIV. Staining is restricted to the apical cell membranes, characteristically invaginated toward the shell membrane, as well as to endothelia of blood vessels present in the mesodermal layer. The occurrence of a membrane-associated CA form at the apical pole of villus cavity cells, when definitively confirmed, would be fairly consistent with the role proposed for these cells in bicarbonate reabsorption from the eggshell so to prevent metabolic acidosis in the embryo during development.

Comparison of the structure, crystallography and composition of eggshells of the guinea fowl and graylag goose.

PubMed

Pérez-Huerta, Alberto; Dauphin, Yannicke

2016-02-01

The structure and composition of the eggshells of two commercial species (guinea fowl and greylag goose) have been studied. Thin sections and scanning electron microcopy show the similarity of the overall structure, but the relative thickness of the layers differs in these two taxa. Atomic force microscopy shows that the different layers are composed of rounded, heterogeneous granules, the diameter of which is between 50 and 100 nm, with a thin cortex. Infrared data and thermogravimetric analyses show that both eggshells are made of calcite, but differing on the quality and quantity when the organic component is considered. Chemical maps show that chemical element distribution is not uniform within a sample, and differs between the species, but with low magnesium content. Electron back scattered diffraction confirms the eggshells are calcite, but the microtexture strongly differs between the two species. Based on the chemical-structural differences, a species-specific biological control on the biomineralization is found, despite the rapid formation of an eggshell. Overall results indicate that to estimate the quality of eggshells, such as resistance to breakage, is not a straightforward process because of the high complexity of avian eggshell biomineralization. Copyright © 2015 Elsevier GmbH. All rights reserved.

Development of the first sphingomyelin biomimetic stationary phase for immobilized artificial membrane (IAM) chromatography.

PubMed

Verzele, Dieter; Lynen, Frédéric; De Vrieze, Mike; Wright, Adrian G; Hanna-Brown, Melissa; Sandra, Pat

2012-01-28

A prototype sphingomyelin stationary phase for Immobilized Artificial Membrane (IAM) chromatography was synthesized by an ultra-short, solid-phase inspired methodology, in which an oxidative release monitoring strategy played a vital role. Evaluated in a proof-of-concept model for blood-brain barrier passage, partial least squares regression demonstrated its potential as an in vitro prediction tool.

Reorganization of lipid domain distribution in giant unilamellar vesicles upon immobilization with different membrane tethers.

PubMed

Sarmento, M J; Prieto, M; Fernandes, Fábio

2012-11-01

Characterization of phase coexistence in biologically relevant lipid mixtures is often carried out through confocal microscopy of giant unilamellar lipid vesicles (GUVs), loaded with fluorescent membrane probes. This last analysis is generally limited to the vesicle hemisphere further away from the coverslip, in order to avoid artifacts induced by the interaction with the solid surface, and immobilization of vesicles is in many cases required in order to carry out intensity, lifetime or single-molecule based microscopy. This is generally achieved through the use of membrane tethers adhering to a coverslip surface. Here, we aimed to determine whether GUV immobilization through membrane tethers induces changes in lipid domain distribution within liposomes displaying coexistence of lipid lamellar phases. Confocal imaging and a Förster resonance energy transfer (FRET) methodology showed that biotinylated phospholipids present significantly different membrane phase partition behavior upon protein binding, depending on the presence or absence of a linker between the lipid headgroup and the biotinyl moiety. Membrane phases enriched in a membrane tether displayed in some cases a dramatically increased affinity for the immobilization surface, effectively driving sorting of lipid domains to the adherent membrane area, and in some cases complete sequestering of a lipid phase to the interaction surface was observed. On the light of these results, we conclude that tethering of lipid membranes to protein surfaces has the potential to drastically reorganize the distribution of lipid domains, and this reorganization is solely dictated by the partition properties of the protein-tether complex. Copyright © 2012 Elsevier B.V. All rights reserved.

Diffusion relaxation times of nonequilibrium isolated small bodies and their solid phase ensembles to equilibrium states

NASA Astrophysics Data System (ADS)

Tovbin, Yu. K.

2017-08-01

The possibility of obtaining analytical estimates in a diffusion approximation of the times needed by nonequilibrium small bodies to relax to their equilibrium states based on knowledge of the mass transfer coefficient is considered. This coefficient is expressed as the product of the self-diffusion coefficient and the thermodynamic factor. A set of equations for the diffusion transport of mixture components is formulated, characteristic scales of the size of microheterogeneous phases are identified, and effective mass transfer coefficients are constructed for them. Allowing for the developed interface of coexisting and immiscible phases along with the porosity of solid phases is discussed. This approach can be applied to the diffusion equalization of concentrations of solid mixture components in many physicochemical systems: the mutual diffusion of components in multicomponent systems (alloys, semiconductors, solid mixtures of inert gases) and the mass transfer of an absorbed mobile component in the voids of a matrix consisting of slow components or a mixed composition of mobile and slow components (e.g., hydrogen in metals, oxygen in oxides, and the transfer of molecules through membranes of different natures, including polymeric).

Solid-Phase Biological Assays for Drug Discovery

NASA Astrophysics Data System (ADS)

Forsberg, Erica M.; Sicard, Clémence; Brennan, John D.

2014-06-01

In the past 30 years, there has been a significant growth in the use of solid-phase assays in the area of drug discovery, with a range of new assays being used for both soluble and membrane-bound targets. In this review, we provide some basic background to typical drug targets and immobilization protocols used in solid-phase biological assays (SPBAs) for drug discovery, with emphasis on particularly labile biomolecular targets such as kinases and membrane-bound receptors, and highlight some of the more recent approaches for producing protein microarrays, bioaffinity columns, and other devices that are central to small molecule screening by SPBA. We then discuss key applications of such assays to identify drug leads, with an emphasis on the screening of mixtures. We conclude by highlighting specific advantages and potential disadvantages of SPBAs, particularly as they relate to particular assay formats.

Ultrastructure of the fetal membranes of the oviparous kingsnake, Lampropeltis getula (Colubridae) as revealed by scanning electron microscopy.

PubMed

Kim, Young K; Blackburn, Daniel G

2015-12-01

In reptilian sauropsids, fetal (extraembryonic) membranes that line the eggshell sustain developing embryos by providing for gas exchange and uptake of water and eggshell calcium. However, a scarcity of morphological studies hinders an understanding of functional specializations and their evolution. In kingsnakes (Lampropeltis getula), scanning electron microscopy reveals two major fetal membranes: the chorioallantois and yolk sac omphalopleure. In early development, the chorioallantois contains tall chorionic epithelial cells, avascular connective tissue, and enlarged allantoic epithelial cells. During its maturation, the chorionic and allantoic epithelia thin dramatically and become underlain by a rich network of allantoic capillaries, yielding a membrane ideally suited for respiratory gas exchange. Yolk sac development initially is like that of typical lizards and snakes, forming an avascular omphalopleure, isolated yolk mass (IYM), and yolk cleft. However, unlike the situation in most squamates studied, the omphalopleure becomes transformed into a "secondary chorioallantois" via three asynchronous events: flattening of the epithelium, regression of the IYM, and vascularization by the allantois. Progressive expansion of chorioallantois parallels growing embryonic needs for gas exchange. In early through mid-development, external surfaces of both the chorionic and omphalopleure epithelium show an abundance of irregular surface protrusions that possibly increase surface area for water absorption. We postulate that the hypertrophied allantoic epithelial cells produce allantoic fluid, a viscous substance that facilitates water uptake and storage. Our findings are consistent with a previous study on the corn snake Pantherophis guttatus, but include new observations and novel functional hypotheses relevant to a reconstruction of basal squamate patterns. © 2015 Wiley Periodicals, Inc.

Method development for the analysis of ionophore antimicrobials in dairy manure to assess removal within a membrane-based treatment system.

PubMed

Hurst, Jerod J; Wallace, Josh S; Aga, Diana S

2018-04-01

Ionophore antimicrobials are heavily used in the livestock industries, both for preventing animal infection by coccidia protozoa and for increasing feed efficiency. Ionophores are excreted mostly unmetabolized and are released into the environment when manure is land-applied to fertilize croplands. Here, an analytical method was optimized to study the occurrences of five ionophore residues (monensin, lasalocid, maduramycin, salinomycin, and narasin) in dairy manure after solid-liquid separation and further treatment of the liquid manure by a membrane-based treatment system. Ionophore residues from the separated solid manure (dewatered manure) and suspended solids of manure slurry samples were extracted using ultrasonication with methanol, followed by sample clean-up using solid phase extraction (SPE) and subsequent analysis via liquid chromatography-tandem mass spectrometry (LC-MS/MS). The use of an ethyl acetate and methanol (1:1 v:v) mixture as an SPE eluent resulted in higher recoveries and lower method quantitation limits (MQL), when compared to using methanol. Overall recoveries from separated solid manure ranged from 73 to 134%. Liquid manure fractions were diluted with Nanopure™ water and cleaned up using SPE, where recoveries ranged from 51 to 100%. The developed extraction and LC-MS/MS methods were applied to analyze dairy manure samples subjected to an advanced manure treatment process involving a membrane-based filtration step (reverse osmosis). Monensin and lasalocid were detected at higher concentrations in the suspended solid fractions (4.40-420 ng/g for lasalocid and 85-1950 ng/g for monensin) compared to the liquid fractions (

Glycerol derivatives of cutin and suberin monomers: synthesis and self-assembly.

PubMed

Douliez, Jean-Paul; Barrault, Joël; Jerome, François; Heredia, Antonio; Navailles, Laurence; Nallet, Frédéric

2005-01-01

Glycerol derivatives of cutin and suberin monomers were synthesized by acid catalysis. Their dispersion in an aqueous solution was examined by phase contrast microscopy, neutron scattering, and solid state NMR. It is shown that the phase behavior strongly depends on the nature of the derivatives forming either lumps of aggregated membranes or well dispersed membranes.

"Reagentless" flow injection determination of ammonia and urea using membrane separation and solid phase basification

NASA Technical Reports Server (NTRS)

Akse, J. R.; Thompson, J. O.; Sauer, R. L.; Atwater, J. E.

1998-01-01

Flow injection analysis instrumentation and methodology for the determination of ammonia and ammonium ions in an aqueous solution are described. Using in-line solid phase basification beds containing crystalline media. the speciation of ammoniacal nitrogen is shifted toward the un-ionized form. which diffuses in the gas phase across a hydrophobic microporous hollow fiber membrane into a pure-water-containing analytical stream. The two streams flow in a countercurrent configuration on opposite sides of the membrane. The neutral pH of the analytical stream promotes the formation of ammonium cations, which are detected using specific conductance. The methodology provides a lower limit of detection of 10 microgram/L and a dynamic concentration range spanning three orders of magnitude using a 315-microliters sample injection volume. Using immobilized urease to enzymatically promote the hydrolysis of urea to produce ammonia and carbon dioxide, the technique has been extended to the determination of urea.

humpty dumpty is required for developmental DNA amplification and cell proliferation in Drosophila.

PubMed

Bandura, Jennifer L; Beall, Eileen L; Bell, Maren; Silver, Hannah R; Botchan, Michael R; Calvi, Brian R

2005-04-26

The full complement of proteins required for the proper regulation of genome duplication are yet to be described. We employ a genetic DNA-replication model system based on developmental amplification of Drosophila eggshell (chorion) genes [1]. Hypomorphic mutations in essential DNA replication genes result in a distinct thin-eggshell phenotype owing to reduced amplification [2]. Here, we molecularly identify the gene, which we have named humpty dumpty (hd), corresponding to the thin-eggshell mutant fs(3)272-9 [3]. We confirm that hd is essential for DNA amplification in the ovary and show that it also is required for cell proliferation during development. Mosaic analysis of hd mutant cells during development and RNAi in Kc cells reveal that depletion of Hd protein results in severe defects in genomic replication and DNA damage. Most Hd protein is found in nuclear foci, and some may traverse the nuclear envelope. Consistent with a role in DNA replication, expression of Hd protein peaks during late G1 and S phase, and it responds to the E2F1/Dp transcription factor. Hd protein sequence is conserved from plants to humans, and published microarrays indicate that expression of its putative human ortholog also peaks at G1/S [4]. Our data suggest that hd defines a new gene family likely required for cell proliferation in all multicellular eukaryotes.

Comparative proteomics of matrix fractions between pimpled and normal chicken eggshells.

PubMed

Liu, Zhangguo; Song, Lingzi; Lu, Lizhi; Zhang, Xianfu; Zhang, Fuming; Wang, Kehua; Linhardt, Robert J

2017-09-07

Eggshell matrix can be dissociated into three matrix fractions: acid-insoluble matrix (M1), water-insoluble matrix (M2) and acid-water facultative-soluble matrix (M3). Matrix fractions from pimpled and normal eggshells were compared using label-free proteomic method to understand the differences among three matrix fractions and the proteins involved with eggshell quality. A total of 738 and 600 proteins were identified in the pimpled and normal calcified eggshells, respectively. Both eggshells showed a combined proteomic inventory of 769 proteins. In the same type of eggshell, a high similarity was present in the proteomes of three matrix fractions. These triply overlapped common proteins formed the predominant contributor to proteomic abundance in the matrix fractions. In each matrix fraction and between both eggshell models, normal and pimpled eggshells, a majority of the proteomes of the fractions were commonly observed. Forty-two common major proteins (iBAQ-derived abundance ≥0.095% of proteomic abundance) were identified throughout the three matrix fractions and these proteins might act as backbone constituents in chicken eggshell matrix. Finally, using 1.75-fold as up-regulated and using 0.57-fold as down-regulated cutoff values, twenty-five differential major proteins were screened and they all negatively influence and none showed any effect on eggshell quality. Overall, we uncovered the characteristics of proteomics of three eggshell matrix fractions and identified candidate proteins influencing eggshell quality. The next research on differential proteins will uncover the potential mechanisms underlying how proteins affect eggshell quality. It was reported that the proteins in an eggshell can be divided into insoluble and soluble proteins. The insoluble proteins are thought to be an inter-mineral matrix and acts as a structural framework, while the soluble proteins are thought as intra-mineral matrix that are embedded within the crystal during calcification. However, the difference between matrix fractions is unknown. Cross-analysis of proteomic data of three matrix fractions from the same type of eggshell, uncovered triply overlapped common proteins formed the predominant contributor to proteomic abundance of any matrix fraction, and we suggested that abundance variance of some common proteins between the three matrix fractions might be an important cause of their solubility differences. Moreover, eggshell is formed in hen's uterus, and uterus tend to be considered as unique organ determining eggshell quality. By cross-analysis on proteomic data of three matrix fractions between two eggshell models, normal and pimpled eggshells, the differential proteins were screened as candidates influencing eggshell quality. And we suggested that the liver and spleen or lymphocytes might be the major organs influencing eggshell quality, because the most promising candidates are almost blood and non-collagenous proteins, and originated from above organs. Copyright © 2017 Elsevier B.V. All rights reserved.

Eggshells as an index of aedine mosquito production. 1: Distribution, movement and sampling of Aedes taeniorhynchus eggshells.

PubMed

Ritchie, S A; Addison, D S; van Essen, F

1992-03-01

The distribution of Aedes taeniorhynchus eggshells in Florida mangrove basin forests was determined and used to design a sampling plan. Eggshells were found in 10/11 sites (91%), with a mean +/- SE density of 1.45 +/- 0.75/cc; density did not change significantly year to year. Highest densities were located on the sloping banks of hummocks, ponds and potholes. Eggshells were less clumped in distribution than eggs and larvae and thus required a smaller sample size for a given precision level. While eggshells were flushed from compact soil that was subject to runoff during heavy rain, mangrove peat, the dominant soil of eggshell-bearing sites, was less dense and had little runoff or eggshell flushing. We suggest that eggshell surveys could be used to identify Ae. taeniorhynchus oviposition sites and oviposition patterns.

A multiphase approach to model ultrafiltration of deformable colloids

NASA Astrophysics Data System (ADS)

Haribabu, Malavika; Dunstan, Dave; Davidson, Malcolm; Harvie, Dalton

2017-11-01

Ultrafiltration (UF) is widely used in the dairy industry to fractionate and concentrate proteins, during the manufacture of milk protein concentrate and cheese. The protein build-up, comprising casein micelles (CM) and whey proteins, at the membrane surface during UF increases the resistance of the membrane system, thereby decreasing the performance of the process unit. CM have a complex structure that hydrodynamically behaves as a hard-sphere when dilute, but deforms beyond the random packing limit, forming a shear-thinning gel. This study employs a mixture model, based on the mixture phase continuity, Navier-Stokes equations, and solids continuity equation, to predict the solid concentration and velocity distribution during UF of CM. Micelle deformation is modelled as a function of volume fraction and dependent on its elastic modulus and particle size. The effect of deformation on gel permeability is implemented via Happel's permeability for hard spheres. Under crossflow conditions, the gel thickness is observed to increase along the membrane length, followed by a decrease towards the end of the membrane, resulting in an increase in flux at the latter section of the membrane. This study demonstrates that the membrane end-effects are important in determining UF performance.

Predicting mercury in mallard ducklings from mercury in chorioallantoic membranes

USGS Publications Warehouse

Heinz, G.H.; Hoffman, D.J.

2003-01-01

Methylmercury has been suspected as a cause of impaired reproduction in wild birds, but the confounding effects of other environmental stressors has made it difficult to determine how much mercury in the eggs of these wild species is harmful. Even when a sample egg can be collected from the nest of a wild bird and the mercury concentration in that egg compared to the laboratory-derived thresholds for reproductive impairment, additional information on the mercury levels in other eggs from that nest would be helpful in determining whether harmful levels of mercury were present in the clutch. The measurement of mercury levels in chorioallantoic membranes offers a possible way to estimate how much mercury was in a chick that hatched from an egg, and also in the whole fresh egg itself. While an embryo is developing, wastes are collected in a sac called the chorioallantoic membranes, which often remain inside the eggshell and can be collected for contaminant analysis. We fed methylmercury to captive mallards to generate a broad range of mercury levels in eggs, allowed the eggs to hatch normally, and then compared mercury concentrations in the hatchling versus the chorioallantoic membranes left behind in the eggshell. When the data from eggs laid by mercury- treated females were expressed as common logarithms, a linear equation was created by which the concentration of mercury in a duckling could be predicted from the concentration of mercury in the chorioallantoic membranes from the same egg. Therefore, if it were not possible to collect a sample egg from a clutch of wild bird eggs, the collection of the chorioallantoic membranes could be substituted, and the mercury predicted to be in the chick or whole egg could be compared to the thresholds of mercury that have been shown to cause harm in controlled feeding studies with pheasants, chickens, and mallards.

Eggshells as an index of aedine mosquito production. 2: Relationship of Aedes taeniorhynchus eggshell density to larval production.

PubMed

Addison, D S; Ritchie, S A; Webber, L A; Van Essen, F

1992-03-01

To test if eggshell density could be used as an index of aedine mosquito production, we compared eggshell density with the larval production of Aedes taeniorhynchus in Florida mangrove basin forests. Quantitative (n = 7) and categorical (n = 34) estimates of annual larval production were regressed against the number of eggshells per cc of soil. Significant regressions were obtained in both instances. Larval production was concentrated in zones with the highest eggshell density. We suggest that eggshell density and distribution can be used to identify oviposition sites and the sequence of larval appearance.

Interaction of curcumin with 1,2-dioctadecanoyl-sn-glycero-3-phosphocholine liposomes: Intercalation of rhamnolipids enhances membrane fluidity, permeability and stability of drug molecule.

PubMed

Moussa, Zeinab; Chebl, Mazhar; Patra, Digambara

2017-01-01

Stability of curcumin in neutral and alkaline buffer conditions has been a serious concern for its medicinal applications. We demonstrate that the stability of curucmin can be improved in 1,2-Dioctadecanoyl-sn-glycero-3-phosphocholine (DSPC) liposomes. Curcumin strongly partition into liquid crystalline phase compared to solid gel phase of DSPC liposomes. Variation of fluorescence intensity of curcumin associated with liposomes with temperature successfully determines phase transition temperature of DSPC liposomes. However, at higher molar ratio curcumin can influence phase transition temperature by intercalating into deep hydrophobic layer of liposomes and facilitating fusion of two membrane phases. Rhamnolipids (RLs) are recently being applied for various biomedical applications. Here, we have explored new insight on intercalation of rhamnolipids with DSPC liposomes. Intercalation of rhamnolipids exceptionally increases partition of curcumin into solid gel phase of DSPC liposomes, whereas this increase is moderate in liquid crystalline phase. Fluorescence quenching study establishes that permeability and fluidity of the DSPC liposomes are enhanced in the presence of RLs. Membrane permeability and fluidity can be improved further by increasing the percentage of RLs in DSPC liposomes. The phase transition temperature of DSPC liposomes decreases with increase in percentage of RLs in DSPC liposomes by encouraging fusion between solid gel and liquid crystalline phases. Intercalation of RLs is found to further boost stability of drug, curcumin, in DSPC liposomes. Thus, mixing RLs with DSPC liposomes could potentially serve as a good candidate for drug delivery application. Copyright © 2016 Elsevier B.V. All rights reserved.

Silicon Nanostructures, Excitonic Interactions, Laser Consequences

DTIC Science & Technology

2008-07-11

etching using an anodized aluminum oxide membrane as mask. The results described here lay a solid foundation for the next phase of development aimed at...achieved though reactive-ion-etching using an anodized aluminum oxide membrane as mask. The results described here lay a solid foundation for the next...Materials, April 4, 2006 issue). 6. Aijun Yin, Marian Tzolov, David Cardimona and Jimmy Xu, "Fabrication of Highly Ordered Anodic Aluminum Oxide

Recovery of salmonella serovar enteritidis from inoculated broiler hatching eggs using shell rinse and shell crush sampling methods

USDA-ARS?s Scientific Manuscript database

This study compared the recovery of Salmonella from hatching eggs using three sampling methods (eggshell rinsing, eggshell crush following a previous rinse, and eggshell crush without previous rinse). Eggshells were drop-inoculated with approximately 10, 100, or 1,000 cfu/eggshell of S. Enteritidis...

Cellulose membrane modified with polypyrrole as an extraction device for the determination of emerging contaminants in river water with GC-MS.

PubMed

de Noronha, Bárbara Viero; Bergamini, Márcio Fernando; Marcolino Junior, Luiz Humberto; da Silva, Bruno José Gonçalves

2018-05-21

In this study, a simple, efficient, and reusable device based on cellulose membranes modified with polypyrrole was developed to extract 14 emerging contaminants from aqueous matrices. For chemical polymerization, a low-cost cellulose membrane was immersed in 0.1 mol L -1 pyrrole and 0.5 mol L -1 ammonium persulfate for 40 min in an ice/water bath. The cellulose membranes modified with polypyrrole were accommodated in a polycarbonate holder suitable for solid-phase extraction disks. Solid-phase extraction parameters that affect extraction efficiency, such as sample volume, pH, flow-rate, and desorption were optimized. Subsequently, determination of target compounds was performed by gas chromatography with mass spectrometry. The linear range for analytes ranged from 0.05 to 500 μg L -1 , with coefficients of determination above 0.990. The limits of quantification varied between 0.05 and 10 μg L -1 , with relative standard deviations lower than 17%. The performance of the proposed cellulose membranes modified with polypyrrole device for real samples was evaluated after extraction of emerging contaminants from a river water sample from the city of Curitiba-Brazil. Bisphenol A (6.39 μg L -1 ), caffeine (17.83 μg L -1 ), and paracetamol (19.28 μg L -1 ) were found in these samples. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Separation Method for Oxygen Mass Transport Coefficient in Two Phase Porous Air Electrodes - Transport in Gas and Solid Polymer or Liquid Electrolyte Phases

DTIC Science & Technology

2013-08-06

of the problem studied Proton exchange membrane fuel cells ( PEMFCs ) are the most promising candidate systems for alternative electricity...characteristic. The limiting current can be used as a tool to study mass transport phenomena in PEMFC because it can provide experimental data for the...coefficient for PEMFCs under in situ conditions based on the galvanostatic discharge of a cell with an interrupted reactant supply. The results indicated

First report of metallic elements in loggerhead and leatherback turtle eggs from the Indian Ocean.

PubMed

du Preez, M; Nel, R; Bouwman, H

2018-04-01

Bio-monitoring of pollutants in long-lived animals such as sea turtles is an important tool in ecotoxicology. We present the first report on metallic elements in sea turtle eggs from the Indian Ocean. Eggs of the leatherback and loggerhead turtle that breed on the Indian Ocean coast of South Africa were analysed for 30 elements. The eggshells and egg contents of the loggerhead turtle, the smaller of the two species, had higher or significantly higher concentrations than leatherbacks, except for strontium - the reason is unknown. Elemental concentrations in eggshells and contents were the same or lower compared with other studies. The differences in concentrations in the egg contents and eggshells between the two species are likely due to different trophic levels, migration patterns, life histories, age, and growth, as well as differences in pollution sources and the uptake, retention and elimination characteristics of the different elements by the different species. We found no congruence between patterns in eggshells and corresponding egg contents, for both species. However, eggshells and egg contents showed congruence between species. The lack of congruence between eggshells and contents within each species precludes using eggshell concentrations as a proxy for egg content concentrations. Copper, strontium, and selenium occurred at concentrations higher than available toxic reverence values. Further research is warranted, including the analyses of POPs, as well as possible deme discrimination based on compositional pattern differences. Turtles serve as 'active samplers' returning to the same location to breed-something that is not practical with marine mammals or elasmobranchs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Immobilization of lead in a Korean military shooting range soil using eggshell waste: an integrated mechanistic approach.

PubMed

Ahmad, Mahtab; Hashimoto, Yohey; Moon, Deok Hyun; Lee, Sang Soo; Ok, Yong Sik

2012-03-30

This study evaluated the effectiveness of eggshell and calcined eggshell on lead (Pb) immobilization in a shooting range soil. Destructive and non-destructive analytical techniques were employed to determine the mechanism of Pb immobilization. The 5% additions of eggshell and calcined eggshell significantly decreased the TCLP-Pb concentration by 68.8% due mainly to increasing soil pH. Eggshell and calcined-eggshell amendments decreased the exchangeable Pb fraction to ≈ 1% of the total Pb in the soil, while the carbonate-associated Pb fraction was increased to 40.0-47.1% at >15% application rates. The thermodynamic modeling on Pb speciation in the soil solution predicted the precipitation of Pb-hydroxide [Pb(OH)(2)] in soils amended with eggshell and calcined eggshell. The SEM-EDS, XAFS and elemental dot mapping revealed that Pb in soil amended with calcined eggshell was associated with Si and Ca, and may be immobilized by entrapping into calcium-silicate-hydrate. Comparatively, in the soil amended with eggshell, Pb was immobilized via formation of Pb-hydroxide or lanarkite [Pb(2)O(SO(4))]. Applications of amendments increased activities of alkaline phosphatase up to 3.7 times greater than in the control soil. The use of eggshell amendments may have potential as an integrated remediation strategy that enables Pb immobilization and soil biological restoration in shooting range soils. Copyright © 2012 Elsevier B.V. All rights reserved.

Morphology of chimpanzee pinworms, Enterobius (Enterobius) anthropopitheci (Gedoelst, 1916) (Nematoda: Oxyuridae), collected from chimpanzees, Pan troglodytes, on Rubondo Island, Tanzania.

PubMed

Hasegawa, Hideo; Ikeda, Yatsukaho; Fujisaki, Akiko; Moscovice, Liza R; Petrzelkova, Klara J; Kaur, Taranjit; Huffman, Michael A

2005-12-01

The chimpanzee pinworm, Enterobius (Enterobius) anthropopitheci (Gedoelst, 1916) (Nematoda: Oxyuridae), is redescribed based on light and scanning electron microscopy of both sexes collected from the feces of chimpanzees, Pan troglodytes, of an introduced population on Rubondo Island, Tanzania. Enterobius (E.) anthropopitheci is characterized by having a small body (males 1.13-1.83 mm long, females 3.33-4.73 mm long), a rather straight spicule with a ventral membranous formation in males, double-crested lateral alae in females, small eggs (53-58 by 24-28 microm), and a smooth eggshell with 3 longitudinal thickenings. Morphological comparison is made between the present and previous descriptions.

Pipe-dependent ventral processing of Easter by Snake is the defining step in Drosophila embryo DV axis formation.

PubMed

Cho, Yong Suk; Stevens, Leslie M; Stein, David

2010-06-22

The establishment of Drosophila embryonic dorsal-ventral (DV) polarity relies on serine proteolytic activity in the perivitelline space between the embryonic membrane and the eggshell. Gastrulation Defective cleaves and activates Snake, which processes and activates Easter, which cleaves Spätzle to form the activating ligand for the Toll receptor. Ventral restriction of ligand formation depends on the Pipe sulfotransferase, which is expressed in ventral cells of the follicular epithelium surrounding the developing oocyte. Pipe modifies components of the developing eggshell to produce a ventral cue embedded in the vitelline membrane. This ventral cue is believed to promote one or more of the proteolysis steps in the perivitelline space. By examining the processing of transgenic, tagged versions of the perivitelline proteins during DV patterning, we find that the proteolysis of Easter by Snake is the first Pipe-dependent step and therefore the key ventrally restricted event in the protease cascade. We also find that Snake and Easter associate together in a complex in both wild-type and pipe mutant-derived embryos. This observation suggests a mechanism in which the sulfated target of Pipe promotes a productive interaction between Snake and Easter, perhaps by facilitating conformational changes in a complex containing the two proteins. Copyright 2010 Elsevier Ltd. All rights reserved.

Purification and characterization of an eggshell membrane decomposing protease from Pseudomonas aeruginosa strain ME-4.

PubMed

Cheng, Minyi; Takenaka, Shinji; Aoki, Shunsuke; Murakami, Shuichiro; Aoki, Kenji

2009-04-01

A bacterial strain, ME-4, isolated from farm soil and identified as Pseudomonas aeruginosa, grew well on a medium containing eggshell membrane (ESM). P. aeruginosa strain ME-4 decomposed the ESM by producing an extracellular protease able to solubilize it. The protease was purified to homogeneity from culture supernatant by fractionation with (NH(4))(2)SO(4), as well as CM52 cellulose and DE52 cellulose column chromatography, with a final yield of 47%. The molecular mass of the enzyme was 33 kDa. The isolated enzyme was a metalloprotease and was strongly inhibited by EDTA, o-phenanthroline, and phosphoramidon. The enzyme inhibited by these reagents was reactivated in the presence of several metal ions. The enzyme acted on various proteins and showed higher activity with collagen than collagenase from Clostridium histolyticum. Results of assays with the FRETS combinatorial libraries revealed that the enzyme preferred Ser at the P1 position and Lys at the P2 position. It also preferred hydrophobic amino acid residues at the P1' and P2' positions. The enzyme showed a much higher solubilization activity with the ESM substrate than commercially obtained enzymes. The enzyme decomposed ESM to produce water-soluble peptides, Val-Leu-Pro-Pro and (X)-Val-Pro-Pro, and a free amino acid, tryptophan.

Rapid and Sensitive Quantification of Vibrio cholerae and Vibrio mimicus Cells in Water Samples by Use of Catalyzed Reporter Deposition Fluorescence In Situ Hybridization Combined with Solid-Phase Cytometry

PubMed Central

Schauer, Sonja; Sommer, Regina; Farnleitner, Andreas H.

2012-01-01

A new protocol for rapid, specific, and sensitive cell-based quantification of Vibrio cholerae/Vibrio mimicus in water samples was developed. The protocol is based on catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH) in combination with solid-phase cytometry. For pure cultures, we were able to quantify down to 6 V. cholerae cells on one membrane with a relative precision of 39% and down to 12 cells with a relative precision of 17% after hybridization with the horseradish peroxidase (HRP)-labeled probe Vchomim1276 (specific for V. cholerae and V. mimicus) and signal amplification. The corresponding position of the probe on the 16S rRNA is highly accessible even when labeled with HRP. For the first time, we were also able to successfully quantify V. cholerae/V. mimicus via solid-phase cytometry in extremely turbid environmental water samples collected in Austria. Cell numbers ranged from 4.5 × 101 cells ml−1 in the large saline lake Neusiedler See to 5.6 × 104 cells ml−1 in an extremely turbid shallow soda lake situated nearby. We therefore suggest CARD-FISH in combination with solid-phase cytometry as a powerful tool to quantify V. cholerae/V. mimicus in ecological studies as well as for risk assessment and monitoring programs. PMID:22885749

Combination of graphene oxide-based solid phase extraction and electro membrane extraction for the preconcentration of chlorophenoxy acid herbicides in environmental samples.

PubMed

Tabani, Hadi; Fakhari, Ali Reza; Shahsavani, Abolfath; Behbahani, Mohammad; Salarian, Mani; Bagheri, Akbar; Nojavan, Saeed

2013-07-26

Combination of different extraction methods is an interesting and debatable work in the field of sample preparation. In the current study, for the first time, solid phase extraction combined with electro membrane extraction (SPE-EME) was developed for ultra-preconcentration and determination of chlorophenoxy acid herbicides in environmental samples using capillary electrophoresis (CE). In the mentioned method, first, a 100mL of chlorophenoxy acid herbicides (2-methyl-4-chlorophenoxyacetic acid (MCPA), 2-(2,4-dichlorophenoxy) propanoic acid (2,4-DP) and 2-(4-chloro-2-methylphenoxy) propanoic acid (MCPP)) was passed through a column of graphene oxide as a solid phase, and then the adsorbed herbicides were eluted by 4.0mL of 8% acetic acid (HOAC) in methanol. Then, the elution solvent was evaporated and the herbicides residue was dissolved in 4.0mL of double distilled water (pH 9.0). Afterwards, the herbicides in 4.0mL of the aqueous solution were transferred to an EME glass vial. In the EME step, the herbicides were extracted from the sample solution into the basic acceptor solution (pH 13.0) under electrical potential, which was held inside the lumen of the fiber with 1-octanol as the supported liquid membrane (SLM). Under the optimized conditions, high enrichment factors were obtained in the range of 1950-2000. The limits of quantification (LOQs) and method detection limits (MDLs) were obtained in the range of 1.0-1.5 and 0.3-0.5ngmL(-1), respectively. Finally, the performance of the present method was evaluated for extraction and determination of chlorophenoxy acid herbicides in environmental samples. Copyright © 2013 Elsevier B.V. All rights reserved.

Variability in avian eggshell colour: a comparative study of museum eggshells.

PubMed

Cassey, Phillip; Portugal, Steven J; Maurer, Golo; Ewen, John G; Boulton, Rebecca L; Hauber, Mark E; Blackburn, Tim M

2010-08-09

The exceptional diversity of coloration found in avian eggshells has long fascinated biologists and inspired a broad range of adaptive hypotheses to explain its evolution. Three main impediments to understanding the variability of eggshell appearance are: (1) the reliable quantification of the variation in eggshell colours; (2) its perception by birds themselves, and (3) its relation to avian phylogeny. Here we use an extensive museum collection to address these problems directly, and to test how diversity in eggshell coloration is distributed among different phylogenetic levels of the class Aves. Spectrophotometric data on eggshell coloration were collected from a taxonomically representative sample of 251 bird species to determine the change in reflectance across different wavelengths and the taxonomic level where the variation resides. As many hypotheses for the evolution of eggshell coloration assume that egg colours provide a communication signal for an avian receiver, we also modelled reflectance spectra of shell coloration for the avian visual system. We found that a majority of species have eggs with similar background colour (long wavelengths) but that striking differences are just as likely to occur between congeners as between members of different families. The region of greatest variability in eggshell colour among closely related species coincided with the medium-wavelength sensitive region around 500 nm. The majority of bird species share similar background eggshell colours, while the greatest variability among species aligns with differences along a red-brown to blue axis that most likely corresponds with variation in the presence and concentration of two tetrapyrrole pigments responsible for eggshell coloration. Additionally, our results confirm previous findings of temporal changes in museum collections, and this will be of particular concern for studies testing intraspecific hypotheses relating temporal patterns to adaptation of eggshell colour. We suggest that future studies investigating the phylogenetic association between the composition and concentration of eggshell pigments, and between the evolutionary drivers and functional impacts of eggshell colour variability will be most rewarding.

Chicken eggshell as suitable calcium source at home.

PubMed

Brun, Lucas R; Lupo, Maela; Delorenzi, Damián A; Di Loreto, Verónica E; Rigalli, Alfredo

2013-09-01

Taken into consideration that the deficiency of calcium (Ca) in the diet is a common problem, the aim of this work was to study the chicken eggshell as Ca source at home. It was evaluated: (1) different mechanisms to process eggshells and find an easy way to determine the required amount of Ca at home and; (2) the flavor and the texture for eggshell fortified food. Chemical and mechanical methods of eggshell processing were evaluated. Changes in flavor and texture were evaluated in volunteers coordinated by a professional chef. A single eggshell contains 2.07 ± 0.18 g of Ca; therefore half an eggshell could provide the amount of Ca needed by adult human beings per day. The best way to use chicken eggshell as Ca dietary supplement is powdered to add to bread, pizza or spaghetti as there were small changes in texture and no changes in flavor.

Structure and Membrane Interactions of the Antibiotic Peptide Dermadistinctin K by Multidimensional Solution and Oriented 15N and 31P Solid-State NMR Spectroscopy

PubMed Central

Verly, Rodrigo M.; Moraes, Cléria Mendonça de; Resende, Jarbas M.; Aisenbrey, Christopher; Bemquerer, Marcelo Porto; Piló-Veloso, Dorila; Valente, Ana Paula; Almeida, Fábio C.L.; Bechinger, Burkhard

2009-01-01

DD K, a peptide first isolated from the skin secretion of the Phyllomedusa distincta frog, has been prepared by solid-phase chemical peptide synthesis and its conformation was studied in trifluoroethanol/water as well as in the presence of sodium dodecyl sulfate and dodecylphosphocholine micelles or small unilamellar vesicles. Multidimensional solution NMR spectroscopy indicates an α-helical conformation in membrane environments starting at residue 7 and extending to the C-terminal carboxyamide. Furthermore, DD K has been labeled with 15N at a single alanine position that is located within the helical core region of the sequence. When reconstituted into oriented phosphatidylcholine membranes the resulting 15N solid-state NMR spectrum shows a well-defined helix alignment parallel to the membrane surface in excellent agreement with the amphipathic character of DD K. Proton-decoupled 31P solid-state NMR spectroscopy indicates that the peptide creates a high level of disorder at the level of the phospholipid headgroup suggesting that DD K partitions into the bilayer where it severely disrupts membrane packing. PMID:19289046

Correlation between the ripple phase and stripe domains in membranes.

PubMed

Bernchou, Uffe; Midtiby, Henrik; Ipsen, John Hjort; Simonsen, Adam Cohen

2011-12-01

We investigate the relationship between stripe domains and the ripple phase in membranes. These have previously been observed separately without being linked explicitly. Past results have demonstrated that solid and ripple phases exhibit rich textural patterns related to the orientational order of tilted lipids and the orientation of ripple corrugations. Here we reveal a highly complex network pattern of ripple and solid domains in DLPC, DPPC bilayers with structures covering length scales from 10 nm to 100 μm. Using spincoated double supported membranes we investigate domains by correlated AFM and fluorescence microscopy. Cooling experiments demonstrate the mode of nucleation and growth of stripe domains enriched in the fluorescent probe. Concurrent AFM imaging reveals that these stripe domains have a one-to-one correspondence with a rippled morphology running parallel to the stripe direction. Both thin and thick stripe domains are observed having ripple periods of 13.5±0.2 nm and 27.4±0.6 nm respectively. These are equivalent to previously observed asymmetric/equilibrium and symmetric/metastable ripple phases, respectively. Thin stripes grow from small solid domains and grow predominantly in length with a speed of ~3 times that of the thick stripes. Thick stripes grow by templating on the sides of thinner stripes or can emerge directly from the fluid phase. Bending and branching angles of stripes are in accordance with an underlying six fold lattice. We discuss mechanisms for the nucleation and growth of ripples and discuss a generic phase diagram that may partly rationalize the coexistence of metastable and stable phases. Copyright © 2011 Elsevier B.V. All rights reserved.

Composite mixed oxide ionic and electronic conductors for hydrogen separation

DOEpatents

Gopalan, Srikanth [Westborough, MA; Pal, Uday B [Dover, MA; Karthikeyan, Annamalai [Quincy, MA; Hengdong, Cui [Allston, MA

2009-09-15

A mixed ionic and electronic conducting membrane includes a two-phase solid state ceramic composite, wherein the first phase comprises an oxygen ion conductor and the second phase comprises an n-type electronically conductive oxide, wherein the electronically conductive oxide is stable at an oxygen partial pressure as low as 10.sup.-20 atm and has an electronic conductivity of at least 1 S/cm. A hydrogen separation system and related methods using the mixed ionic and electronic conducting membrane are described.

Solid phase extraction membrane

DOEpatents

Carlson, Kurt C [Nashville, TN; Langer, Roger L [Hudson, WI

2002-11-05

A wet-laid, porous solid phase extraction sheet material that contains both active particles and binder and that possesses excellent wet strength is described. The binder is present in a relatively small amount while the particles are present in a relatively large amount. The sheet material is sufficiently strong and flexible so as to be pleatable so that, for example, it can be used in a cartridge device.

Structure-function relationship of avian eggshell matrix proteins: a comparative study of two major eggshell matrix proteins, ansocalcin and OC-17.

PubMed

Lakshminarayanan, Rajamani; Joseph, Jeremiah S; Kini, R Manjunatha; Valiyaveettil, Suresh

2005-01-01

The role of individual matrix proteins in avian eggshell calcification is poorly understood despite numerous attempts to characterize and localize their presence in the eggshell matrix. Ansocalcin, the major matrix protein from goose eggshell, was found to induce the formation of calcite crystal aggregates under in vitro. Owing to its high similarity with the chicken eggshell matrix protein ovocleidin 17 (OC-17), a comparative investigation has been carried out to understand the structure-function relationship. RP-HPLC shows that ansocalcin is the major component in extracts of goose eggshells before and after bleach treatment. However, OC-17 was observed in minute quantities in the extract of bleach-treated chicken eggshells. In vitro crystal growth experiments showed that OC-17 and ansocalcin interact differently with the calcite crystals formed. Circular dichroism, intrinsic tryptophan fluorescence, and dynamic light scattering studies showed that, under the conditions used in our experiments, OC-17 does not aggregate in solution or induce the nucleation of calcite aggregates in the concentration range used. These observations indicate that OC-17 and ansocalcin play different roles in the eggshell calcification. To our knowledge, this is the first report on the comparison of properties of homologous eggshell proteins that belong to the same phylogeny.

Synthesis of fatty acid methyl ester from palm oil (Elaeis guineensis) with Ky(MgCa)2xO3 as heterogeneous catalyst.

PubMed

Olutoye, M A; Lee, S C; Hameed, B H

2011-12-01

Fatty acid methyl esters (FAME) were produced from palm oil using eggshell modified with magnesium and potassium nitrates to form a composite, low-cost heterogeneous catalyst for transesterification. The catalyst, prepared by the combination of impregnation/co-precipitation was calcined at 830 °C for 4 h. Transesterification was conducted at a constant temperature of 65 °C in a batch reactor. Design of experiment (DOE) was used to optimize the reaction parameters, and the conditions that gave highest yield of FAME (85.8%) was 5.35 wt.% catalyst loading at 4.5 h with 16:1 methanol/oil molar ratio. The results revealed that eggshell, a solid waste, can be utilized as low-cost catalyst after modification with magnesium and potassium nitrates for biodiesel production. Copyright © 2011 Elsevier Ltd. All rights reserved.

Comparative transcriptome analysis provides clues to molecular mechanisms underlying blue-green eggshell color in the Jinding duck (Anas platyrhynchos).

PubMed

Wang, Zhepeng; Meng, Guohua; Bai, Yun; Liu, Ruifang; Du, Yu; Su, Lihong

2017-09-12

In birds, blue-green eggshell color (BGEC) is caused by biliverdin, a bile pigment derived from the degradation of heme and secreted in the eggshell by the shell gland. Functionally, BGEC might promote the paternal investment of males in the nest and eggs. However, little is known about its formation mechanisms. Jinding ducks (Anas platyrhynchos) are an ideal breed for research into the mechanisms, in which major birds lay BGEC eggs with minor individuals laying white eggs. Using this breed, this study aimed to provide insight into the mechanisms via comparative transcriptome analysis. Blue-shelled ducks (BSD) and white-shelled ducks (WSD) were selected from two populations, forming 4 groups (3 ducks/group): BSD1 and WSD1 from population 1 and BSD2 and WSD2 from population 2. Twelve libraries from shell glands were sequenced using the Illumina RNA-seq platform, generating an average of 41 million clean reads per library, of which 55.9% were mapped to the duck reference genome and assembled into 31,542 transcripts. Expression levels of 11,698 genes were successfully compared between all pairs of 4 groups. Of these, 464 candidate genes were differentially expressed between cross-phenotype groups, but not for between same-phenotype groups. Gene Ontology (GO) annotation showed that 390 candidate genes were annotated with 2234 GO terms. No candidate genes were directly involved in biosynthesis or transport of biliverdin. However, the integral components of membrane, metal ion transport, cholesterol biosynthesis, signal transduction, skeletal system development, and chemotaxis were significantly (P < 0.05) overrepresented by candidate genes. This study identified 464 candidate genes associated with duck BGEC, providing valuable information for a better understanding of the mechanisms underlying this trait. Given the involvement of membrane cholesterol contents, ions and ATP levels in modulating the transport activity of bile pigment transporters, the data suggest a potential association between duck BGEC and the transport activity of the related transporters.

Crystallization around solid-like nanosized docks can explain the specificity, diversity, and stability of membrane microdomains.

PubMed

de Almeida, Rodrigo F M; Joly, Etienne

2014-01-01

To date, it is widely accepted that microdomains do form in the biological membranes of all eukaryotic cells, and quite possibly also in prokaryotes. Those sub-micrometric domains play crucial roles in signaling, in intracellular transport, and even in inter-cellular communications. Despite their ubiquitous distribution, and the broad and lasting interest invested in those microdomains, their actual nature and composition, and even the physical rules that regiment their assembly still remain elusive and hotly debated. One of the most often considered models is the raft hypothesis, i.e., the partition of lipids between liquid disordered and ordered phases (Ld and Lo, respectively), the latter being enriched in sphingolipids and cholesterol. Although it is experimentally possible to obtain the formation of microdomains in synthetic membranes through Ld/Lo phase separation, there is an ever increasing amount of evidence, obtained with a wide array of experimental approaches, that a partition between domains in Ld and Lo phases cannot account for many of the observations collected in real cells. In particular, it is now commonly perceived that the plasma membrane of cells is mostly in Lo phase and recent data support the existence of gel or solid ordered domains in a whole variety of live cells under physiological conditions. Here, we present a model whereby seeds comprised of oligomerised proteins and/or lipids would serve as crystal nucleation centers for the formation of diverse gel/crystalline nanodomains. This could confer the selectivity necessary for the formation of multiple types of membrane domains, as well as the stability required to match the time frames of cellular events, such as intra- or inter-cellular transport or assembly of signaling platforms. Testing of this model will, however, require the development of new methods allowing the clear-cut discrimination between Lo and solid nanoscopic phases in live cells.

Eggshell structure in Caiman latirostris eggs improves embryo survival during nest inundation.

PubMed

Cedillo-Leal, César; Simoncini, Melina S; Leiva, Pamela M L; Larriera, Alejandro; Lang, Jeffrey W; Piña, Carlos I

2017-05-17

Egg inundation often results in poor hatching success in crocodylians. However, how tolerant eggs are to submergence, and/or how eggshell ultrastructure may affect embryo survival when inundated, are not well understood. In this study, our objective was to determine if embryo survival in Caiman latirostris is affected by eggshell surface roughness, when eggs are submerged under water. Tolerance to inundation was tested early (day 30) versus late (day 60) in development, using eight clutches (four per time treatments), subdivided into four groups: ( N = 9 per clutch per treatment; 9 × 4 = 36 eggs per group). 'Rough' eggshell represented the natural, unmodified eggshell surface structure. 'Smooth' eggshell surface structure was created by mechanically sanding the natural rough surface to remove surface columnar elements and secondary layer features, e.g. irregularities that result in 'roughness'. When inundated by submerging eggs under water for 10 h at day 30, 'smooth' eggshell structure resulted in more than twice as many dead embryos (16 versus 6, smooth versus rough; N = 36), and fewer than half as many healthy embryos (6 versus 13, smooth versus rough, respectively; N = 36). By contrast, at day 60, inundation resulted in very low hatching success, regardless of eggshell surface structure. Only two hatchlings survived the inundation, notably in the untreated group with intact, rough eggshells. Inundation produced a high rate of malformations (58% at day 30), but did not affect hatchling size. Our results indicate that eggshell roughness enhances embryo survival when eggs are inundated early in development, but not late in development. Apparently, the natural surface 'roughness' entraps air bubbles at the eggshell surface during inundation, thereby facilitating gas exchange through the eggshell even when the egg is submerged under water. © 2017 The Author(s).

Gas chromatographic determination of polycyclic aromatic hydrocarbons in water and smoked rice samples after solid-phase microextraction using multiwalled carbon nanotube loaded hollow fiber.

PubMed

Matin, Amir Abbas; Biparva, Pourya; Gheshlaghi, Mohammad

2014-12-29

A novel solid-phase microextraction fiber was prepared based on multiwalled carbon nanotubes (MWCNTs) loaded on hollow fiber membrane pores. Stainless steel wire was used as unbreakable support. The major advantages of the proposed fiber are its (a) high reproducibility due to the uniform structure of the hollow fiber membranes, (b) high extraction capacity related to the porous structure of the hollow fiber and outstanding adsorptive characteristics of MWCNTs. The proposed fiber was applied for the microextraction of five representative polycyclic aromatic hydrocarbons (PAHs) from aqueous media (river and hubble-bubble water) and smoked rice samples followed by gas chromatographic determination. Analytical merits of the method, including high correlation coefficients [(0.9963-0.9992) and (0.9982-0.9999)] and low detection limits [(9.0-13.0ngL(-1)) and (40.0-150.0ngkg(-1))] for water and rice samples, respectively, made the proposed method suitable for the ultra-trace determination of PAHs. Copyright © 2014 Elsevier B.V. All rights reserved.

Nanowire membrane-based nanothermite: towards processable and tunable interfacial diffusion for solid state reactions.

PubMed

Yang, Yong; Wang, Peng-peng; Zhang, Zhi-cheng; Liu, Hui-ling; Zhang, Jingchao; Zhuang, Jing; Wang, Xun

2013-01-01

Interfacial diffusion is of great importance in determining the performance of solid-state reactions. For nanometer sized particles, some solid-state reactions can be triggered accidently by mechanical stress owing to their large surface-to-volume ratio compared with the bulk ones. Therefore, a great challenge is the control of interfacial diffusion for solid state reactions, especially for energetic materials. Here we demonstrate, through the example of nanowire-based thermite membrane, that the thermite solid-state reaction can be easily tuned via the introduction of low-surface-energy coating layer. Moreover, this silicon-coated thermite membrane exhibit controlled wetting behavior ranging from superhydrophilic to superhydrophobic and, simultaneously, to significantly reduce the friction sensitivity of thermite membrane. This effect enables to increase interfacial resistance by increasing the amount of coating material. Indeed, our results described here make it possible to tune the solid-state reactions through the manipulation of interfacial diffusion between the reactants.

Nanowire Membrane-based Nanothermite: towards Processable and Tunable Interfacial Diffusion for Solid State Reactions

NASA Astrophysics Data System (ADS)

Yang, Yong; Wang, Peng-Peng; Zhang, Zhi-Cheng; Liu, Hui-Ling; Zhang, Jingchao; Zhuang, Jing; Wang, Xun

2013-04-01

Interfacial diffusion is of great importance in determining the performance of solid-state reactions. For nanometer sized particles, some solid-state reactions can be triggered accidently by mechanical stress owing to their large surface-to-volume ratio compared with the bulk ones. Therefore, a great challenge is the control of interfacial diffusion for solid state reactions, especially for energetic materials. Here we demonstrate, through the example of nanowire-based thermite membrane, that the thermite solid-state reaction can be easily tuned via the introduction of low-surface-energy coating layer. Moreover, this silicon-coated thermite membrane exhibit controlled wetting behavior ranging from superhydrophilic to superhydrophobic and, simultaneously, to significantly reduce the friction sensitivity of thermite membrane. This effect enables to increase interfacial resistance by increasing the amount of coating material. Indeed, our results described here make it possible to tune the solid-state reactions through the manipulation of interfacial diffusion between the reactants.

Heavy metals and metalloids in egg contents and eggshells of passerine birds from Arizona

USGS Publications Warehouse

Mora, Miguel A.

2003-01-01

Concentrations of inorganic elements were determined in eggs of passerine birds including the endangered southwestern willow flycatcher (Empidonax traillii extimus) from four regions in Arizona. The main aim of the study was to determine the distribution of metals in egg contents and eggshells, with emphasis on the deposition of Sr in eggshells. Seventy eggs of 11 passerine species were collected at four nesting locations during 2000. Aluminum, Ba, Cr, Cu, Mn, Se, Sr, and Zn, were detected primarily in egg contents of all bird species. Arsenic, Ni, Pb, and V were detected primarily in eggshells. A proportion of most inorganic elements accumulated in the eggshell. Concentrations of Ba, Cu, Mn, Se, Sr, and Zn in egg contents and As, Ba, Cu, and V in eggshells of yellow-breasted chats (Icteria virens) were similar among locations. However, concentrations of Mn, Ni, Sr, and Zn in eggshells were significant different among locations. Except for Cu, Mn, Se, and Zn, concentrations of inorganic elements were 2–35 times greater in eggshells than in eggs. Most concentrations of metals and metalloids in eggs and eggshells of all the bird species were below levels known to affect reproduction or that have other deleterious effects. However, I found somewhat elevated concentrations of Sr in eggshells (highest mean=1505 μg/g dw, n=3) of yellow-breasted chats and willow flycatchers, and in egg contents of yellow warblers (Dendroica petechia) and song sparrows (Melospiza melodia). Whether current observed concentrations of Sr in eggshells are affecting nesting birds in Arizona remains to be determined. Strontium and other metals could be associated with lower hatching success in some areas. This study shows that a proportion of many inorganic elements accumulates in the eggshell and that the potential effects on the proper structure and functioning of the eggshell should not be ignored.

Microstructure, crystallography and diagenetic alteration in fossil ostrich eggshells from Upper Palaeolithic sites of Indian peninsular region.

PubMed

Jain, Sonal; Bajpai, Sunil; Kumar, Giriraj; Pruthi, Vikas

2016-05-01

Biominerals studies are of importance as they provide an understanding of natural evolutionary processes. In this study we have investigated the fossil ostrich eggshells using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Electron Backscatter Diffraction (EBSD). SEM studies demonstrated the ultrastructure of fossil eggshells and formation of calcified cuticular layer. The presence of calcified cuticle layer in eggshell is the basis for ancient DNA studies as it contains preserved biomolecules. EBSD accentuates the crystallographic structure of the ostrich eggshells with sub-micrometer resolution. It is a non-destructive tool for evaluating the extent of diagenesis in a biomineral. EBSD analysis revealed the presence of dolomite in the eggshells. This research resulted in the complete recognition of the structure of ostrich eggshells as well as the nature and extent of diagenesis in these eggshells which is vital for genetic and paleoenvironmental studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

The thermomechanical stability of micro-solid oxide fuel cells fabricated on anodized aluminum oxide membranes

NASA Astrophysics Data System (ADS)

Kwon, Chang-Woo; Lee, Jae-Il; Kim, Ki-Bum; Lee, Hae-Weon; Lee, Jong-Ho; Son, Ji-Won

2012-07-01

The thermomechanical stability of micro-solid oxide fuel cells (micro-SOFCs) fabricated on an anodized aluminum oxide (AAO) membrane template is investigated. The full structure consists of the following layers: AAO membrane (600 nm)/Pt anode/YSZ electrolyte (900 nm)/porous Pt cathode. The utilization of a 600-nm-thick AAO membrane significantly improves the thermomechanical stability due to its well-known honeycomb-shaped nanopore structure. Moreover, the Pt anode layer deposited in between the AAO membrane and the YSZ electrolyte preserves its integrity in terms of maintaining the triple-phase boundary (TPB) and electrical conductivity during high-temperature operation. Both of these results guarantee thermomechanical stability of the micro-SOFC and extend the cell lifetime, which is one of the most critical issues in the fabrication of freestanding membrane-type micro-SOFCs.

Two phase microstructure for Ag-Ni nanowires

NASA Astrophysics Data System (ADS)

Srivastava, Chandan; Rai, Rajesh Kumar

2013-03-01

In the present study, electrodeposition technique was used to produce Ag-Ni nanowires. Ag-Ni system shows extremely high bulk immiscibility. Nanowire morphology was achieved by employing an anodic alumina membrane having pores of ˜200 nm diameter. Microstructure of as-deposited wire was composed of nano-sized solid solution structured Ag-Ni nanoparticles embedded in a matrix of pure Ag phase. It is proposed that the two phase microstructure resulted from an initial formation of solid solution structured nanoparticles in the alumina template pore followed by nucleation of pure Ag phase over the particles which eventually grew to form the matrix phase.

Solid polymer electrolyte (SPE) fuel cell technology program, phase 2/2A. [testing and evaluations

NASA Technical Reports Server (NTRS)

1976-01-01

Test evaluations were performed on a fabricated single solid polymer electrolyte cell unit. The cell operated at increased current density and at higher performance levels. This improved performance was obtained through a combination of increased temperature, increased reactant pressures, improved activation techniques and improved thermal control over the baseline cell configuration. The cell demonstrated a higher acid content membrane which resulted in increased performance. Reduced catalyst loading and low cost membrane development showed encouraging results.

Novel amphiphilic polymeric ionic liquid-solid phase micro-extraction membrane for the preconcentration of aniline as degradation product of azo dye Orange G under sonication by liquid chromatography-tandem mass spectrometry.

PubMed

Cai, Mei-Qiang; Wei, Xiao-Qing; Du, Chun-Hui; Ma, Xu-Ming; Jin, Mi-Cong

2014-07-04

A novel amphiphilic polymeric ionic liquid membrane containing a hydrophilic bromide anion and a hydrophobic carbonyl group was synthesized in dimethylformamide (DMF) systems using the ionic liquid 1-butyl-3-vinylimidazolium bromide (BVImBr) and the methylmethacrylate (MMA) as monomers. The prepared amphiphilic ploy-methylmethacrylate-1-butyl-3-vinylimidazolium bromide (MMA-BVImBr) was characterized by a scanning electron microscope and an infrared spectrum instrument. The results of solid-phase micro-extraction membrane (SPMM) experiments showed that the adsorption capacity of membrane was about 0.76μgμg(-1) for aniline. Based on this, a sensitive method for the determination of trace aniline, as a degradation product of azo dye Orange G under sonication, was developed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The calibration curve showed a good linearity ranging from 0.5 to 10.0μgL(-1) with a correlation coefficient value of 0.9998. The limit of quantification was 0.5μgL(-1). The recoveries ranged from 90.6% to 96.1%. The intra- and inter-day relative standard deviations were less than 8.3% and 10.9%. The developed SPMM-LC-MS/MS method was used successfully for preconcentration of trace aniline produced during the sonication of Orange G solution. Copyright © 2014 Elsevier B.V. All rights reserved.

Biodegradation of thermoplastic starch/eggshell powder composites.

PubMed

Bootklad, Munlika; Kaewtatip, Kaewta

2013-09-12

Thermoplastic starch (TPS) was prepared using compression molding and chicken eggshell was used as a filler. The effect of the eggshell powder (EP) on the properties of TPS was compared with the effect of commercial calcium carbonate (CC). The organic compound on the surface of the eggshell powder acted as a coupling agent that resulted in a strong adhesion between the eggshell powder and the TPS matrix, as confirmed by SEM micrographs. The biodegradation was determined by the soil burial test. The TPS/EP composites were more rapidly degraded than the TPS/CC composites. In addition, the eggshell powder improved the water resistance and thermal stability of the TPS. Copyright © 2013 Elsevier Ltd. All rights reserved.

Assessment of co-composting process with high load of an inorganic industrial waste.

PubMed

Soares, Micaela A R; Quina, Margarida J; Reis, Marco S; Quinta-Ferreira, Rosa

2017-01-01

This study aims to investigate the co-composting of an inorganic industrial waste (eggshell - ES) in very high levels (up to 60% w/w). Since composting is a process in which solid, liquid and gaseous phases interact in a very complex way, there is a need to shed light on statistical tools that can unravel the main relationships structuring the variability associated to this process. In this study, PCA and data visualisation were used with that purpose. The co-composting tests were designed with increasing quantities of ES (0, 10, 20, 30 and 60%ES w/w) mixed with industrial potato peel and rice husks. Principal component analysis showed that physical properties like free air space, bulk density and moisture are the most relevant variables for explaining the variability due to ES content. On the other hand, variability in time dynamics is mostly driven by some chemical and phytoxicological parameters, such as organic matter decay and nitrate content. Higher ES incorporation (60% ES) enhanced the initial biological activity of the mixture, but the higher bulk density and lower water holding capacity had a negative effect on the aerobic biological activity as the process evolved. Nevertheless, pathogen-killing temperatures (>70°C for 11h) were attained. All the final products obtained after 90days were stable and non-phytotoxic. This work proved that valorisation of high amounts of eggshell by co-composting is feasible, but prone to be influenced by the physical properties of the mixtures. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fuel Cells Using the Protic Ionic Liquid and Rotator Phase Solid Electrolyte Principles

DTIC Science & Technology

2008-02-13

Talk “High temperature Polymer Electrolyte Membrane Fuel Cells (HT- PEMFCs ) for Portable Power in Large-Scale Energy Storage Devices”, Paper Number 195...Membrane Fuel Cells (HT- PEMFCs ) for Portable Power in Large-Scale Energy Storage Devices”, Paper Number 195, 212th Meeting of the Electrochemical

Mercury concentrations in eggshells of the Southern Ground-Hornbill (Bucorvus leadbeateri) and Wattled Crane (Bugeranus carunculatus) in South Africa.

PubMed

Daso, Adegbenro P; Okonkwo, Jonathan O; Jansen, Raymond; Brandao, José D D O; Kotzé, Antoinette

2015-04-01

In this study, wild hatched eggshells were collected from the nests of threatened Wattled Crane and South Ground-Hornbill in an attempt to determine their total Hg concentrations. A total of fourteen eggshell samples from both bird species were collected from different study areas in the Mpumlanga and KwaZulu-Natal Provinces of South Africa. The eggshells were acid digested under reflux and their total Hg concentrations were determined using cold-vapour atomic absorption spectrophotometry (CV-AAS). The observed total Hg levels for the South Ground-Hornbill samples ranged from 1.31 to 8.88 µg g(-1) dry weight (dw), except for one outlier which had an elevated 75.0 µg g(-1) dw. The levels obtained for the Wattled Crane samples were relatively high and these ranged from 14.84 to 36.37 µg g(-1) dw. Generally, all the measured total Hg concentrations for the Wattled Crane samples exceeded the estimated total Hg levels derived for eggshell which were known to cause adverse reproductive effects in avian species from previous studies. Based on these findings, it is, therefore, possible that the exposure of these birds to elevated Hg may have contributed to their present population decline. Copyright © 2015 Elsevier Inc. All rights reserved.

Variability and interaction of some egg physical and eggshell quality attributes during the entire laying hen cycle.

PubMed

Sirri, F; Zampiga, M; Berardinelli, A; Meluzzi, A

2018-05-01

The aim of this study was to investigate the variability and relationships between some egg physical (egg weight, width, length, shape index, and surface area) and eggshell parameters (weight and percentage, thickness, breaking strength, and L*, a*, and b* values) during the entire laying hen cycle. A total of 8,000 eggs was collected every 5 wk, from 30 to 81 wk of hen age (10 samplings of 400 eggs/house), in 2 identical poultry houses equipped with enriched cages. For the statistical analysis, ANOVA, Bivariate Correlation, Principal Component Analysis (PCA), and Hierarchical Cluster Analysis were used. An increase of egg weight, length, and eggshell lightness (L*) associated with a reduction of eggshell percentage, breaking strength, and redness (a*) was observed as the hen aged (P < 0.05). Overall, the coefficients of variation resulted in <5% in width, length, shape index, and egg surface area; from 5 to 10% of egg weight, shell weight, shell percentage, shell thickness, L*, and b*; and >10% of eggshell breaking strength and a*. According to the PCA, the highest changes during the laying cycle are related to egg physical parameters (32%) and to eggshell breaking strength, percentage, and thickness (26%). The egg physical parameters appeared to be strongly correlated to each other, whereas a slight correlation between eggshell breaking strength and color attributes were evidenced (-0.231 and 0.289, respectively, for L* and a*; P < 0.01). Hierarchical cluster analysis, based on principal components of the overall egg attributes, is hereby considered, and evidenced dissimilarities for eggs laid from peak production up for 39 wk of hen age from the eggs laid afterwards. The latter group could also be divided into 2 subgroups, one comprising eggs laid from 44 and 53 wk of hen age and the other from 58 wk to the end. In conclusion, the large dataset created in this study allowed to extrapolate some robust information regarding the variability and correlations of the egg physical and eggshell quality attributes throughout the entire laying hen cycle.

Fluorescent sensor systems based on nanostructured polymeric membranes for selective recognition of Aflatoxin B1.

PubMed

Sergeyeva, Tetyana; Yarynka, Daria; Piletska, Elena; Lynnik, Rostyslav; Zaporozhets, Olga; Brovko, Oleksandr; Piletsky, Sergey; El'skaya, Anna

2017-12-01

Nanostructured polymeric membranes for selective recognition of aflatoxin B1 were synthesized in situ and used as highly sensitive recognition elements in the developed fluorescent sensor. Artificial binding sites capable of selective recognition of aflatoxin B1 were formed in the structure of the polymeric membranes using the method of molecular imprinting. A composition of molecularly imprinted polymer (MIP) membranes was optimized using the method of computational modeling. The MIP membranes were synthesized using the non-toxic close structural analogue of aflatoxin B1, ethyl-2-oxocyclopentanecarboxylate as a dummy template. The MIP membranes with the optimized composition demonstrated extremely high selectivity towards aflatoxin B1 (AFB1). Negligible binding of close structural analogues of AFB1 - aflatoxins B2 (AFB2), aflatoxin G2 (AFG2), and ochratoxin A (OTA) was demonstrated. Binding of AFB1 by the MIP membranes was investigated as a function of both type and concentration of the functional monomer in the initial monomer composition used for the membranes' synthesis, as well as sample composition. The conditions of the solid-phase extraction of the mycotoxin using the MIP membrane as a stationary phase (pH, ionic strength, buffer concentration, volume of the solution, ratio between water and organic solvent, filtration rate) were optimized. The fluorescent sensor system based on the optimized MIP membranes provided a possibility of AFB1 detection within the range 14-500ngmL -1 demonstrating detection limit (3Ϭ) of 14ngmL -1 . The developed technique was successfully applied for the analysis of model solutions and waste waters from bread-making plants. Copyright © 2017 Elsevier B.V. All rights reserved.

Xp11.2 translocation renal cell carcinoma with egg-shell calcification mimicking a benign renal tumour: A case report.

PubMed

Liang, Wenjie; Xu, Shunliang

2015-11-01

The present study reports the case of a 20-year-old female who was identified to have a left renal angiomyolipoma (AML) with hemorrhage. Following temporary conservative observation, the patient received continuous ultrasonic follow-up. Due to the rapid growth of the lesion, further examinations were performed. Computed tomography (CT) plain scans revealed a partly high-density mass with marginal egg-shell calcification. Enhanced CT revealed a solid tumor with a rich blood supply. Since no fats were detected, the possibility of a typical AML was excluded, but the diagnoses of epithelioid AML or renal cancer were considered. Finally, the left kidney was partially excised laparoscopically. The intraoperative frozen section indicated a diagnosis of renal cell carcinoma (RCC). The left kidney was subsequently radically excised. Routine histopathological and immunohistochemical tests confirmed that the lesion was an RCC with an Xp11.2 translocation. The present study introduces the pitfalls in the diagnosis of Xp11.2 translocation RCC, which is a rare RCC subtype accompanied with uncommon imaging manifestations. The study suggests that when a rapidly-growing AML is detected by ultrasound, renal cancer with marginal calcification should be considered. Moreover, although egg-shell calcification mostly occurs in benign renal lesions, further examinations, such as enhanced CT, are recommended for identifying the nature of the masses and excluding the possibility of malignant tumors.

Xp11.2 translocation renal cell carcinoma with egg-shell calcification mimicking a benign renal tumour: A case report

PubMed Central

LIANG, WENJIE; XU, SHUNLIANG

2015-01-01

The present study reports the case of a 20-year-old female who was identified to have a left renal angiomyolipoma (AML) with hemorrhage. Following temporary conservative observation, the patient received continuous ultrasonic follow-up. Due to the rapid growth of the lesion, further examinations were performed. Computed tomography (CT) plain scans revealed a partly high-density mass with marginal egg-shell calcification. Enhanced CT revealed a solid tumor with a rich blood supply. Since no fats were detected, the possibility of a typical AML was excluded, but the diagnoses of epithelioid AML or renal cancer were considered. Finally, the left kidney was partially excised laparoscopically. The intraoperative frozen section indicated a diagnosis of renal cell carcinoma (RCC). The left kidney was subsequently radically excised. Routine histopathological and immunohistochemical tests confirmed that the lesion was an RCC with an Xp11.2 translocation. The present study introduces the pitfalls in the diagnosis of Xp11.2 translocation RCC, which is a rare RCC subtype accompanied with uncommon imaging manifestations. The study suggests that when a rapidly-growing AML is detected by ultrasound, renal cancer with marginal calcification should be considered. Moreover, although egg-shell calcification mostly occurs in benign renal lesions, further examinations, such as enhanced CT, are recommended for identifying the nature of the masses and excluding the possibility of malignant tumors. PMID:26722310

Nanowire Membrane-based Nanothermite: towards Processable and Tunable Interfacial Diffusion for Solid State Reactions

PubMed Central

Yang, Yong; Wang, Peng-peng; Zhang, Zhi-cheng; Liu, Hui-ling; Zhang, Jingchao; Zhuang, Jing; Wang, Xun

2013-01-01

Interfacial diffusion is of great importance in determining the performance of solid-state reactions. For nanometer sized particles, some solid-state reactions can be triggered accidently by mechanical stress owing to their large surface-to-volume ratio compared with the bulk ones. Therefore, a great challenge is the control of interfacial diffusion for solid state reactions, especially for energetic materials. Here we demonstrate, through the example of nanowire-based thermite membrane, that the thermite solid-state reaction can be easily tuned via the introduction of low-surface-energy coating layer. Moreover, this silicon-coated thermite membrane exhibit controlled wetting behavior ranging from superhydrophilic to superhydrophobic and, simultaneously, to significantly reduce the friction sensitivity of thermite membrane. This effect enables to increase interfacial resistance by increasing the amount of coating material. Indeed, our results described here make it possible to tune the solid-state reactions through the manipulation of interfacial diffusion between the reactants. PMID:23603809

A Membrane-Free Ferrocene-Based High-Rate Semiliquid Battery.

PubMed

Ding, Yu; Zhao, Yu; Yu, Guihua

2015-06-10

We report here a ferrocene-based membrane-free, high-rate semiliquid battery that takes advantage of a highly soluble ferrocene/ferrocenium redox couple in nonaqueous phase. The designed battery exhibits stable capacity retention up to 94% of theoretical capacity of ferrocene (145 mAh g(-1)) at a broad current rate up to 60 C owing to rapid mass transport in a liquid phase and fast redox kinetics. The diffusion coefficient and the standard reaction constant are determined to be in the order of 10(-6) cm(2) s(-1) and 10(-1) cm s(-1), respectively, orders of magnitude greater than those in a solid-phase electrode and those in conventional redox flow batteries. Additionally, the battery demonstrates power density and energy density exceeding 1400 W L(-1) and 40 Wh L(-1), respectively, and stable cyclability with capacity retention of ∼80% for 500 cycles. Compared with state-of-the-art energy storage technologies such as Li-ion batteries or conventional redox flow batteries, the proposed liquid battery shows the potential to be an efficient energy storage system with exceptionally high power and reasonable energy density.

The relationship between the density of Aedes vigilax (Diptera: Culicidae) eggshells and environmental factors on Kooragang Island, New South Wales, Australia.

PubMed

Turner, P A; Streever, W J

1997-12-01

Knowledge of oviposition sites selected by wetland mosquitoes could improve mosquito control and guide wetland rehabilitation practices to avoid creating or exacerbating a mosquito problem. Two studies that enumerated Aedes vigilax eggshells found in salt marsh soil on the western portion of Kooragang Island in New South Wales, Australia, allowed an evaluation of oviposition sites. In one study, the density of eggshells found in samples collected from a large area was related to environmental factors, including distance from nearby drainage channels, vegetation cover, elevation, and terrain characteristics. Multiple-regression analysis suggested eggshell densities were positively correlated with the presence of depressions and ponds, vegetation cover, and distance from culverts, but negatively related to elevation. In another study, eggshell density was related to relative elevation and vegetation species within each of two 400-m2 plots on Kooragang Island. In all but one instance, samples from bare soil contained fewer eggshells than samples with vegetation cover at both plots. Eggshell density did not differ between the two dominant vegetation species, Sarcocornia quinqueflora and Sporobolus virginicus, although bare soil of one plot had a mean eggshell density similar to that of soil with S. quinqueflora cover. Eggshells were at highest density at intermediate elevations at one plot but at low elevations at the other.

The Rheological Properties of Lipid Monolayers Modulate the Incorporation of l-Ascorbic Acid Alkyl Esters.

PubMed

Díaz, Yenisleidy de Las Mercedes Zulueta; Mottola, Milagro; Vico, Raquel V; Wilke, Natalia; Fanani, María Laura

2016-01-19

In this work, we tested the hypothesis that the incorporation of amphiphilic drugs into lipid membranes may be regulated by their rheological properties. For this purpose, two members of the l-ascorbic acid alkyl esters family (ASCn) were selected, ASC16 and ASC14, which have different rheological properties when organized at the air/water interface. They are lipophilic forms of vitamin C used in topical pharmacological preparations. The effect of the phase state of the host lipid membranes on ASCn incorporation was explored using Langmuir monolayers. Films of pure lipids with known phase states have been selected, showing liquid-expanded, liquid-condensed, and solid phases as well as pure cholesterol films in liquid-ordered state. We also tested ternary and quaternary mixed films that mimic the properties of cholesterol containing membranes and of the stratum corneum. The compressibility and shear properties of those monolayers were assessed in order to define its phase character. We found that the length of the acyl chain of the ASCn compounds induces differential changes in the rheological properties of the host membrane and subtly regulates the kinetics and extent of the penetration process. The capacity for ASCn uptake was found to depend on the phase state of the host film. The increase in surface pressure resultant after amphiphile incorporation appears to be a function of the capacity of the host membrane to incorporate such amphiphile as well as the rheological response of the film. Hence, monolayers that show a solid phase state responded with a larger surface pressure increase to the incorporation of a comparable amount of amphiphile than liquid-expanded ones. The cholesterol-containing films, including the mixture that mimics stratum corneum, allowed a very scarce ASCn uptake independently of the membrane diffusional properties. This suggests an important contribution of Cho on the maintenance of the barrier function of stratum corneum.

Changes in mineral composition of eggshells from black ducks and mallards fed DDE in the diet

USGS Publications Warehouse

Longcore, J.R.; Samson, F.B.; Kreitzer, J.F.; Spann, J.W.

1971-01-01

Diets containing 10 and 30 ppm (dry weight) DDE were fed to black ducks, and diets containing 1, 5, and 10 ppm (dry weight) DDE were fed to mallards. Among the results were the following changes in black duck eggshell composition: (a) significant increase in the percentage of Mg, (b) significant decreases in Ba and Sr, (c) increases (which approached significance) in average percentage of eggshell Na and Cu, (d) a decrease in shell Ca which approached significance, (e) patterns of mineral correlations which in some instances were distinct to dosage groups, and (f) inverse correlations in the control group between eggshell thickness Mg and Na. Changes in mallard eggshells were: (a) significant increase in percentage of magnesium at 5 and 10 ppm DDE, (b) significant decrease in Al at 5 and 10 ppm DDE, (c) a significant decrease in Ca from eggshells from the 10 ppm DDE group, and (d) an increase in average percentage of Na in eggshells from DDE dosed ducks which approached significance.

Test of a mosquito eggshell isolation method and subsampling procedure.

PubMed

Turner, P A; Streever, W J

1997-03-01

Production of Aedes vigilax, the common salt-marsh mosquito, can be assessed by determining eggshell densities found in soil. In this study, 14 field-collected eggshell samples were used to test a subsampling technique and compare eggshell counts obtained with a flotation method to those obtained by direct examination of sediment (DES). Relative precision of the subsampling technique was assessed by determining the minimum number of subsamples required to estimate the true mean and confidence interval of a sample at a predetermined confidence level. A regression line was fitted to cube-root transformed eggshell counts obtained from flotation and DES and found to be significant (P < 0.001, r2 = 0.97). The flotation method allowed processing of samples in about one-third of the time required by DES, but recovered an average of 44% of the eggshells present. Eggshells obtained with the flotation method can be used to predict those from DES using the following equation: DES count = [1.386 x (flotation count)0.33 - 0.01]3.

Sexually dimorphic tridimensionally preserved pterosaurs and their eggs from China.

PubMed

Wang, Xiaolin; Kellner, Alexander W A; Jiang, Shunxing; Wang, Qiang; Ma, Yingxia; Paidoula, Yahefujiang; Cheng, Xin; Rodrigues, Taissa; Meng, Xi; Zhang, Jialiang; Li, Ning; Zhou, Zhonghe

2014-06-16

The pterosaur record is generally poor, with little information about their populations, and pterosaur eggs are even rarer, with only four isolated and flattened eggs found to date. We report here a population of a new sexually dimorphic pterosaur species (Hamipterus tianshanensis gen. et sp. nov.), with five exceptionally well-preserved three-dimensional eggs, from the Early Cretaceous deposit in northwestern China. About 40 male and female individuals in total were recovered, but the actual number associated might be in the hundreds. All of the discovered skulls have crests, which exhibit two different morphologies in size, shape, and robustness. The eggs show pliable depressions with cracking and crazing on the outer surface. The eggshell, observed by scanning electron microscopy and energy-dispersive spectroscopy, comprises a thin calcareous external hard shell followed by a soft membrane. These fossils shed new light on the reproductive strategy, ontogeny, and behavior of pterosaurs. The cranial crests show sexually dimorphic morphologies, with presumed males and females differing in crest size, shape, and robustness. Ontogenetic variation is reflected mainly in the expansion of the rostrum. The eggs have some external rigidity of the general pliable eggshell, and the microstructure of the eggshell is similar to that of some modern "soft" snake eggs. We suggest that this new pterosaur nested in colonies and thus exhibited gregarious behavior, a possible general trend for at least derived pterodactyloid pterosaurs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Visual colorimetry for trace antimony(V) by ion-pair solid-phase extraction with bis[2-(5-chloro-2-pyridylazo)-5-diethylaminophenolato]cobalt(III) on a PTFE type membrane filter.

PubMed

Mizuguchi, Hitoshi; Matsuda, Yuki; Mori, Takehito; Uehara, Atsushi; Ishikawa, Yuta; Endo, Masatoshi; Shida, Junichi

2008-02-01

A new visual colorimetry for trace antimony(V) based on ion-pair solid-phase extraction to a PTFE-type membrane filter with bis[2-(5-chloro-2-pyridylazo)-5-diethylaminophenolato]cobalt(III) ion ([Co(5-Cl-PADAP)(2)](+)) has been developed. Experiments showed that hexachloroantimonate(V) ion (SbCl(6)(-)) was adsorbed with [Co(5-Cl-PADAP)(2)](+) to the front surface of the PTFE filter. The adsorption of antimony(V) ion was promoted by the addition of lithium chloride as a source of chloride ion. The excess reagent of [Co(5-Cl-PADAP)(2)](+) was eluted by rinsing with a 10 wt% methanol aqueous solution. In this case, the slow rate of the hydrolysis reaction of SbCl(6)(-) and the difference of the hydrophobicity of the ion pairs were important for adsorption and separation with a PTFE-type membrane filter. The antimony(V) concentration was determined through a visual comparison with a standard series. The visual detection limit was 0.10 microg. The calibration curve assessed with the reflection spectrometric responses at 580 nm was linear in the concentration range of 0.10 - 1.2 microg (r = 0.996). The proposed method has been applied to the determination of sub-microgram levels of antimony(V) ion in water samples.

Catalytic wet air oxidation of coke-plant wastewater on ruthenium-based eggshell catalysts in a bubbling bed reactor.

PubMed

Yang, M; Sun, Y; Xu, A H; Lu, X Y; Du, H Z; Sun, C L; Li, C

2007-07-01

Catalytic wet air of coke-plant wastewater was studied in a bubbling bed reactor. Two types of supported Ru-based catalysts, eggshell and uniform catalysts, were employed. Compared with the results in the wet air oxidation of coke-plant wastewater, supported Ru uniform catalysts showed high activity for chemical oxygen demand (COD) and ammonia/ammonium compounds (NH3-N) removal at temperature of 250 degrees C and pressure of 4.8 MPa, and it has been demonstrated that the catalytic activity of uniform catalyst depended strongly on the distribution of active sites of Ru on catalyst. Compared to the corresponding uniform catalysts with the same Ru loading (0.25 wt.% and 0.1 wt.%, respectively), the eggshell catalysts showed higher activities for CODcr removal and much higher activities for NH3-N degradation. The high activity of eggshell catalyst for treatment of coke-plant wastewater can be attributed to the higher density of active Ru sites in the shell layer than that of the corresponding uniform catalyst with the same Ru loading. It has been also evidenced that the active Ru sites in the internal core of uniform catalyst have very little or no contribution to CODcr and NH3-N removal in the total oxidation of coke-plant wastewater.

Modeling Mass and Thermal Transport in Thin Porous Media of PEM Fuel Cells

NASA Astrophysics Data System (ADS)

Konduru, Vinaykumar

Water transport in the Porous Transport Layer (PTL) plays an important role in the efficient operation of polymer electrolyte membrane fuel cells (PEMFC). Excessive water content as well as dry operating conditions are unfavorable for efficient and reliable operation of the fuel cell. The effect of thermal conductivity and porosity on water management are investigated by simulating two-phase flow in the PTL of the fuel cell using a network model. In the model, the PTL consists of a pore-phase and a solid-phase. Different models of the PTLs are generated using independent Weibull distributions for the pore-phase and the solid-phase. The specific arrangement of the pores and solid elements is varied to obtain different PTL realizations for the same Weibull parameters. The properties of PTL are varied by changing the porosity and thermal conductivity. The parameters affecting operating conditions include the temperature, relative humidity in the flow channel and voltage and current density. In addition, a novel high-speed capable Surface Plasmon Resonance (SPR) microscope was built based on Kretschmann's configuration utilizing a collimated Kohler illumination. The SPR allows thin film characterization in a thickness of approximately 0-200nm by measuring the changes in the refractive index. Various independent experiments were run to measure film thickness during droplet coalescence during condensation.

Bacteriological contamination, dirt, and cracks of eggshells in furnished cages and noncage systems for laying hens: an international on-farm comparison.

PubMed

De Reu, K; Rodenburg, T B; Grijspeerdt, K; Messens, W; Heyndrickx, M; Tuyttens, F A M; Sonck, B; Zoons, J; Herman, L

2009-11-01

For laying hens, the effects of housing system on bacterial eggshell contamination and eggshell quality is almost exclusively studied in experimental hen houses. The aim of this study was to compare eggshell hygiene and quality under commercial conditions. Six flocks of laying hens in furnished cages and 7 flocks in noncage systems were visited when hens were about 60 wk of age. Farms from Belgium, the Netherlands, and Germany were included in the study. The following parameters were determined on eggs sampled at the egg belts: 1) bacterial eggshell contamination, as expressed by total count of aerobic bacteria and number of Enterobacteriaceae; 2) proportion of dirty eggs; and 3) proportion of cracked eggs and eggs with microcracks. Considerable within-flock differences were found in eggshell contamination with total count of aerobic bacteria, both for furnished cages (P < or = 0.001, range 4.24 to 5.22 log cfu/eggshell) and noncage systems (P < or = 0.001, range 4.35 to 5.51 log cfu/eggshell). On average, lower levels of contamination with total count of aerobic bacteria (4.75 vs. 4.98 log cfu/eggshell; P < or = 0.001) were found on eggshells from furnished cages compared with noncage systems. Concerning Enterobacteriaceae, no significant difference in average eggshell contamination between both systems could be shown. The total percentage of cracked eggs was higher (P < or = 0.01) in furnished cages (7.8%) compared with noncage systems (4.1%). This was, however, due to the high percentage of cracked eggs (24%) observed on one of the furnished cage farms. We conclude that bacteriological eggshell contamination and percentage of cracked eggs differed substantially between individual farms using the same housing system. This may also explain some discrepancies between the findings of the present study versus some findings of previous experimental studies or studies on a small number of farms. Although statistically significant, the average differences in bacteriological contamination of nest eggs between both housing systems have limited microbiological relevancy.

Use of unnatural amino acids to probe structure-activity relationships and mode-of-action of antimicrobial peptides.

PubMed

Tossi, Alessandro; Scocchi, Marco; Zahariev, Sotir; Gennaro, Renato

2012-01-01

Endogenous antimicrobial peptides (AMPs) can have multimodal mechanisms of bacterial inactivation, such as membrane lysis, interference with cell wall biosynthesis or membrane-based protein machineries, or translocation through the membrane to intracellular targets. The controlled variation of side-chain characteristics in their amino acid residues can provide much useful information on structure-activity relationships and mode-of-action, and also lead to improved activities. The small size and relatively low complexity of AMPs make them amenable to solid-phase peptide synthesis, facilitating the use of nonproteinogenic amino acids and vastly increasing the accessible molecular diversity of side chains. Here, we describe how such residues can be used to modulate such key parameters as cationicity, hydrophobicity, steric factors conformational stability, and H-bonding.

Oxygen isotope fractionation between bird eggshell calcite and body water: application to fossil eggs from Lanzarote (Canary Islands).

PubMed

Lazzerini, Nicolas; Lécuyer, Christophe; Amiot, Romain; Angst, Delphine; Buffetaut, Eric; Fourel, François; Daux, Valérie; Betancort, Juan Francisco; Flandrois, Jean-Pierre; Marco, Antonio Sánchez; Lomoschitz, Alejandro

2016-10-01

Oxygen and carbon isotope compositions of fossil bird eggshell calcite (δ(18)Ocalc and δ(13)Ccalc) are regularly used to reconstruct paleoenvironmental conditions. However, the interpretation of δ(18)Ocalc values of fossil eggshells has been limited to qualitative variations in local climatic conditions as oxygen isotope fractionations between calcite, body fluids, and drinking water have not been determined yet. For this purpose, eggshell, albumen water, and drinking water of extant birds have been analyzed for their oxygen and carbon isotope compositions. Relative enrichments in (18)O relative to (16)O between body fluids and drinking water of +1.6 ± 0.9 ‰ for semi-aquatic birds and of +4.4 ± 1.9 ‰ for terrestrial birds are observed. Surprisingly, no significant dependence to body temperature on the oxygen isotope fractionation between eggshell calcite and body fluids is observed, suggesting that bird eggshells precipitate out of equilibrium. Two empirical equations relating the δ(18)Ocalc value of eggshell calcite to the δ(18)Ow value of ingested water have been established for terrestrial and semi-aquatic birds. These equations have been applied to fossil eggshells from Lanzarote in order to infer the ecologies of the Pleistocene marine bird Puffinus sp. and of the enigmatic giant birds from the Pliocene. Both δ(13)Ccalc and δ(18)Ocalc values of Puffinus eggshells point to a semi-aquatic marine bird ingesting mostly seawater, whereas low δ(13)Ccalc and high δ(18)Ocalc values of eggshells from the Pliocene giant bird suggest a terrestrial lifestyle. This set of equations can help to quantitatively estimate the origin of waters ingested by extinct birds as well as to infer either local environmental or climatic conditions.

Oxygen isotope fractionation between bird eggshell calcite and body water: application to fossil eggs from Lanzarote (Canary Islands)

NASA Astrophysics Data System (ADS)

Lazzerini, Nicolas; Lécuyer, Christophe; Amiot, Romain; Angst, Delphine; Buffetaut, Eric; Fourel, François; Daux, Valérie; Betancort, Juan Francisco; Flandrois, Jean-Pierre; Marco, Antonio Sánchez; Lomoschitz, Alejandro

2016-10-01

Oxygen and carbon isotope compositions of fossil bird eggshell calcite (δ18Ocalc and δ13Ccalc) are regularly used to reconstruct paleoenvironmental conditions. However, the interpretation of δ18Ocalc values of fossil eggshells has been limited to qualitative variations in local climatic conditions as oxygen isotope fractionations between calcite, body fluids, and drinking water have not been determined yet. For this purpose, eggshell, albumen water, and drinking water of extant birds have been analyzed for their oxygen and carbon isotope compositions. Relative enrichments in 18O relative to 16O between body fluids and drinking water of +1.6 ± 0.9 ‰ for semi-aquatic birds and of +4.4 ± 1.9 ‰ for terrestrial birds are observed. Surprisingly, no significant dependence to body temperature on the oxygen isotope fractionation between eggshell calcite and body fluids is observed, suggesting that bird eggshells precipitate out of equilibrium. Two empirical equations relating the δ18Ocalc value of eggshell calcite to the δ18Ow value of ingested water have been established for terrestrial and semi-aquatic birds. These equations have been applied to fossil eggshells from Lanzarote in order to infer the ecologies of the Pleistocene marine bird Puffinus sp. and of the enigmatic giant birds from the Pliocene. Both δ13Ccalc and δ18Ocalc values of Puffinus eggshells point to a semi-aquatic marine bird ingesting mostly seawater, whereas low δ13Ccalc and high δ18Ocalc values of eggshells from the Pliocene giant bird suggest a terrestrial lifestyle. This set of equations can help to quantitatively estimate the origin of waters ingested by extinct birds as well as to infer either local environmental or climatic conditions.

Effect of long-term selection for egg production on eggshell quality of Japanese quail (Coturnix japonica).

PubMed

Fathi, M M; El-Dlebshany, A E; El-Deen, M Bahie; Radwan, L M; Rayan, G N

2016-11-01

An experiment was conducted to evaluate egg quality and ultrastuctural measurements of eggshell using a Scanning Electron Microscope (SEM) in 2 lines (selected and control) of Japanese quail. A selection program was applied over 22 consecutive generations for higher egg production and lower broken egg percentage. The results revealed that the females of the selected line produced significantly (P < 0.01) higher egg mass compared to that of the control line. Also, the selection procedure significantly improved feed conversion ratio. The eggshells of the selected line had a higher breaking strength compared to those of the control line, although there was no difference between them in shell thickness. Significantly higher wet (P < 0.01) and dry (P < 0.05) eggshell percentages were found in the selected line. In general, the eggshells of the selected line had a lower total score (good) of ultrastructural evaluation compared to the control line. According to scanning electron microscope data, the incidence of certain structural variants was more common in eggshells of the control line suggesting poor shell strength. The incidence of alignment was more prevalent in control eggshells compared to selected ones, suggesting lower resistance to breakage. Late fusion and large interstitial spaces of the palisade layer indicating decreased resistance to fracture were observed in control eggshells. It could be concluded that the improvement eggshell quality may be caused by the long-term selection for lower cracked and broken egg rates from generation to generation. © 2016 Poultry Science Association Inc.

Trace-element interactions in Rook Corvus frugilegus eggshells along an urbanisation gradient.

PubMed

Orłowski, Grzegorz; Kasprzykowski, Zbigniew; Dobicki, Wojciech; Pokorny, Przemysław; Wuczyński, Andrzej; Polechoński, Ryszard; Mazgajski, Tomasz D

2014-11-01

Concentrations of seven trace elements [arsenic (As), chromium (Cr), nickel (Ni), lead (Pb), copper (Cu), zinc (Zn), and cadmium (Cd)] in the eggshells of Rooks Corvus frugilegus, a focal bird species of Eurasian agricultural environments, are increased above background levels and exceed levels of toxicological concern. The concentrations of Cr, Ni, Pb, Cu, and Zn are greater in eggshells from urban rookeries (large cities) compared with rural areas (small towns and villages) suggesting an urbanisation gradient effect among eggs laid by females. In the present study, the investigators assessed whether the pattern of relationships among the seven trace elements in eggshells change along an urbanisation/pollution gradient. Surprisingly, we found that eggshells with the greatest contaminant burden, i.e., from urban rookeries, showed far fewer significant relationships (n = 4) than eggshells from villages (n = 10), small towns (n = 6), or rural areas (n = 8). In most cases, the relationships were positive. As was an exception: Its concentration was negatively correlated with Ni and Cd levels in eggshells from small town rookeries (where As levels were the highest), whereas eggshells from villages (with a lower As level) showed positive relationships between As and Cd. Our findings suggest that at low to intermediate levels, interactions between the trace elements in Rook eggshells are of a synergistic character and appear to operate as parallel coaccumulation. A habitat-specific excess of some elements (primarily Cr, Ni, Cu, As) suggests their more competitively selective sequestration.

Multicomponent Transport through Realistic Zeolite Membranes: Characterization & Transport in Nanoporous Networks

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

William C. Conner

These research studies focused on the characterization and transport for porous solids which comprise both microporosity and mesoporosity. Such materials represent membranes made from zeolites as well as for many new nanoporous solids. Several analytical sorption techniques were developed and evaluated by which these multi-dimensional porous solids could be quantitatively characterized. Notably an approach by which intact membranes could be studied was developed and applied to plate-like and tubular supported zeolitic membranes. Transport processes were studied experimentally and theoretically based on the characterization studies.

External characteristic determination of eggs and cracked eggs identification using spectral signature

PubMed Central

Xie, Chuanqi; He, Yong

2016-01-01

This study was carried out to use hyperspectral imaging technique for determining color (L*, a* and b*) and eggshell strength and identifying cracked chicken eggs. Partial least squares (PLS) models based on full and selected wavelengths suggested by regression coefficient (RC) method were established to predict the four parameters, respectively. Partial least squares-discriminant analysis (PLS-DA) and RC-partial least squares-discriminant analysis (RC-PLS-DA) models were applied to identify cracked eggs. PLS models performed well with the correlation coefficient (rp) of 0.788 for L*, 0.810 for a*, 0.766 for b* and 0.835 for eggshell strength. RC-PLS models also obtained the rp of 0.771 for L*, 0.806 for a*, 0.767 for b* and 0.841 for eggshell strength. The classification results were 97.06% in PLS-DA model and 88.24% in RC-PLS-DA model. It demonstrated that hyperspectral imaging technique has the potential to be used to detect color and eggshell strength values and identify cracked chicken eggs. PMID:26882990

Application of Colorimetric Solid Phase Extraction (C-SPE) to Monitoring Nickel(II) and Lead(II) in Spacecraft Water Supplies

NASA Technical Reports Server (NTRS)

Diaz, Neil C.; Gazda, Daniel B.; Fritz, James S.; Porter, Marc D.; Rutz, Jeff; Mudgett, Paul; Schultz, John

2004-01-01

Archived water samples collected on the International Space Station (ISS) and returned to Earth for analysis have, in a few instances, contained trace levels of heavy metals. Building on our previous advances using Colorimetric Solid Phase Extraction (C-SPE) as a biocide monitoring technique, we are devising methods for the low level monitoring of nickel(II), lead(II) and other heavy metals. C-SPE is a sorption-spectrophotometric platform based on the extraction of analytes onto a membrane impregnated with a colorimetric reagent that are then quantified on the surface of the membrane using a diffuse reflectance spectrophotometer. Along these lines, we have determined nickel(II) via complexation with dimethylglyoxime (DMG) and begun to examine the analysis of lead(II) by its reaction with 2,5- dimercapto-1,3,4-thiadiazole (DMTD) and 4-(2- pyridylazo)-resorcinol (PAR). These developments are also extending a new variant of C-SPE in which immobilized reagents are being incorporated into this methodology in order to optimize sample reaction conditions and to introduce the colorimetric reagent. This paper describes the status of our development of these two new methods.

Solid-Liquid Electrolyte as a Nanoion Modulator for Dendrite-Free Lithium Anodes.

PubMed

Wen, Kaihua; Wang, Yanlei; Chen, Shimou; Wang, Xi; Zhang, Suojiang; Archer, Lynden A

2018-06-20

Rechargeable lithium (Li) metal batteries are considered the most promising of Li-based energy storage technologies. However, tree-like dendrite produced by irregular Li + electrodeposition restricts it wide applications. Herein, based on a cation-microphase-regulation strategy, we create solid-liquid electrolytes (SLEs) by absorbing commercial liquid electrolytes into polyethylene glycol (PEG) engineered nanoporous Al 2 O 3 ceramic membranes. By means of molecular dynamics simulations and comprehensive experiments, we show that Li ions are regulated and promoted in the two microphases, the channel phase and nonchannel phase, respectively. The channel phase can achieve homogeneous Li + flux distribution by multiple mechanisms, including its uniform array of nanochannels and ability to suppress lateral dendrite growth by its high modulus. In the nonchannel phase, PEG chains swollen by electrolyte facilitate desolvation and fast conduction of Li + . As a result, the studied SLEs exhibit high ionic conductivity, low interfacial resistance, and the unique ability to stabilize deposition at the Li anode. By means of galvanostatic cycling studies in symmetric Li cells and Li/Li 4 Ti 5 O 12 cells, we further show that the materials open a path to Li metal batteries with excellent cycling performance.

Ultra-thin Solid-State Li-Ion Electrolyte Membrane Facilitated by a Self-Healing Polymer Matrix.

PubMed

Whiteley, Justin M; Taynton, Philip; Zhang, Wei; Lee, Se-Hee

2015-11-18

Thin solid membranes are formed by a new strategy, whereby an in situ derived self-healing polymer matrix that penetrates the void space of an inorganic solid is created. The concept is applied as a separator in an all-solid-state battery with an FeS2 -based cathode and achieves tremendous performance for over 200 cycles. Processing in dry conditions represents a paradigm shift for incorporating high active-material mass loadings into mixed-matrix membranes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dynamics of bacterial and fungal communities associated with eggshells during incubation

PubMed Central

Grizard, Stéphanie; Dini-Andreote, Francisco; Tieleman, B Irene; Salles, Joana F

2014-01-01

Microorganisms are closely associated with eggs and may play a determinant role in embryo survival. Yet, the majority of studies focusing on this association relied on culture-based methodology, eventually leading to a skewed assessment of microbial communities. By targeting the 16S rRNA gene and internal transcribed spacer (ITS) region, we, respectively, described bacterial and fungal communities on eggshells of the homing pigeon Columba livia. We explored their structure, abundance, and composition. Firstly, we showed that sampling technique affected the outcome of the results. While broadly used, the egg swabbing procedure led to a lower DNA extraction efficiency and provided different profiles of bacterial communities than those based on crushed eggshell pieces. Secondly, we observed shifts in bacterial and fungal communities during incubation. At late incubation, bacterial communities showed a reduction in diversity, while their abundance increased, possibly due to the competitive advantage of some species. When compared to their bacterial counterparts, fungal communities also decreased in diversity at late incubation. In that case, however, the decline was associated with a diminution of their overall abundance. Conclusively, our results showed that although incubation might inhibit microbial growth when compared to unincubated eggs, we observed the selective growth of specific bacterial species during incubation. Moreover, we showed that fungi are a substantial component of the microbial communities associated with eggshells and require further investigations in avian ecology. Identifying the functional roles of these microorganisms is likely to provide news insights into the evolutionary strategies that control embryo survival. We aimed to describe the dynamics of bacterial and fungal communities on homing pigeon eggshell surfaces. We investigated these communities at early and late incubation stages. PMID:24772289

Automated Water-Purification System

NASA Technical Reports Server (NTRS)

Ahlstrom, Harlow G.; Hames, Peter S.; Menninger, Fredrick J.

1988-01-01

Reverse-osmosis system operates and maintains itself with minimal human attention, using programmable controller. In purifier, membranes surround hollow cores through which clean product water flows out of reverse-osmosis unit. No chemical reactions or phase changes involved. Reject water, in which dissolved solids concentrated, emerges from outer membrane material on same side water entered. Flow controls maintain ratio of 50 percent product water and 50 percent reject water. Membranes expected to last from 3 to 15 years.

New precursors for direct synthesis of single phase Na- and K-{beta}{double_prime}-aluminas for use in AMTEC systems

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

Cook, R.L.; MacQueen, D.B.; Bader, K.E.

1997-12-31

Alkali Metal Thermoelectric Converters (AMTEC) are efficient direct energy conversion devices that depend on the use of highly conductive beta-alumina membranes for their operation. The key component of the AMTEC system is a highly conductive Na-{beta}{double_prime}-alumina solid electrolyte which conducts sodium ions from the high to low temperature zone, thereby generating electricity. AMTEC cells convert thermal to electrical energy by using heat to produce and maintain an alkali metal concentration gradient across the ion transporting BASE membrane. They have developed a method for producing pure phase Na-{beta}{double_prime}-alumina and K-{beta}{double_prime}-alumina powders from single phase nano-sized carboxylato-alumoxanes precursors. Sodium or potassium ionsmore » (the mobile ions) and either Mg{sup 2+} or Li{sup +} ions (which stabilize the {beta}{double_prime}-alumina structure) can be atomically dispersed into the carboxylato-alumoxane lattice at low (< 100 C) temperature. Calculation of the carboxylato-alumoxane precursors at 1,200--1,500 C produces pure phase {beta}{double_prime}-alumina powders.« less

Lipophilic oligonucleotides spontaneously insert into lipid membranes, bind complementary DNA strands, and sequester into lipid-disordered domains.

PubMed

Bunge, Andreas; Kurz, Anke; Windeck, Anne-Kathrin; Korte, Thomas; Flasche, Wolfgang; Liebscher, Jürgen; Herrmann, Andreas; Huster, Daniel

2007-04-10

For the development of surface functionalized bilayers, we have synthesized lipophilic oligonucleotides to combine the molecular recognition mechanism of nucleic acids and the self-assembly characteristics of lipids in planar membranes. A lipophilic oligonucleotide consisting of 21 thymidine units and two lipophilic nucleotides with an alpha-tocopherol moiety as a lipophilic anchor was synthesized using solid-phase methods with a phosphoramadite strategy. The interaction of the water soluble lipophilic oligonucleotide with vesicular lipid membranes and its capability to bind complementary DNA strands was studied using complementary methods such as NMR, EPR, DSC, fluorescence spectroscopy, and fluorescence microscopy. This oligonucleotide inserted stably into preformed membranes from the aqueous phase. Thereby, no significant perturbation of the lipid bilayer and its stability was observed. However, the non-lipidated end of the oligonucleotide is exposed to the aqueous environment, is relatively mobile, and is free to interact with complementary DNA strands. Binding of the complementary single-stranded DNA molecules is fast and accomplished by the formation of Watson-Crick base pairs, which was confirmed by 1H NMR chemical shift analysis and fluorescence resonance energy transfer. The molecular structure of the membrane bound DNA double helix is very similar to the free double-stranded DNA. Further, the membrane bound DNA double strands also undergo regular melting. Finally, in raft-like membrane mixtures, the lipophilic oligonucleotide was shown to preferentially sequester into liquid-disordered membrane domains.

Particle-based simulations of bilayer membranes: self-assembly, structural analysis, and shock-wave damage

NASA Astrophysics Data System (ADS)

Steinhauser, Martin O.; Schindler, Tanja

2017-01-01

We report on the results of particle-based, coarse-grained molecular dynamics simulations of amphiphilic lipid molecules in aqueous environment where the membrane structures at equilibrium are subsequently exposed to strong shock waves, and their damage is analyzed. The lipid molecules self-assemble from unbiased random initial configurations to form stable bilayer membranes, including closed vesicles. During self-assembly of lipid molecules, we observe several stages of clustering, starting with many small clusters of lipids, gradually merging together to finally form one single bilayer membrane. We find that the clustering of lipids sensitively depends on the hydrophobic interaction h_c of the lipid tails in our model and on temperature T of the system. The self-assembled bilayer membranes are quantitatively analyzed at equilibrium with respect to their degree of order and their local structure. We also show that—by analyzing the membrane fluctuations and using a linearized theory— we obtain area compression moduli K_A and bending stiffnesses κ _B for our bilayer membranes which are within the experimental range of in vivo and in vitro measurements of biological membranes. We also discuss the density profile and the pair correlation function of our model membranes at equilibrium which has not been done in previous studies of particle-based membrane models. Furthermore, we present a detailed phase diagram of our lipid model that exhibits a sol-gel transition between quasi-solid and fluid domains, and domains where no self-assembly of lipids occurs. In addition, we present in the phase diagram the conditions for temperature T and hydrophobicity h_c of the lipid tails of our model to form closed vesicles. The stable bilayer membranes obtained at equilibrium are then subjected to strong shock waves in a shock tube setup, and we investigate the damage in the membranes due to their interaction with shock waves. Here, we find a transition from self-repairing membranes (reducing their damage after impact) and permanent (irreversible) damage, depending on the shock front speed. The here presented idea of using coarse-grained (CG) particle models for soft matter systems in combination with the investigation of shock-wave effects in these systems is a quite new approach.

PNA-encoded chemical libraries.

PubMed

Zambaldo, Claudio; Barluenga, Sofia; Winssinger, Nicolas

2015-06-01

Peptide nucleic acid (PNA)-encoded chemical libraries along with DNA-encoded libraries have provided a powerful new paradigm for library synthesis and ligand discovery. PNA-encoding stands out for its compatibility with standard solid phase synthesis and the technology has been used to prepare libraries of peptides, heterocycles and glycoconjugates. Different screening formats have now been reported including selection-based and microarray-based methods that have yielded specific ligands against diverse target classes including membrane receptors, lectins and challenging targets such as Hsp70. Copyright © 2015 Elsevier Ltd. All rights reserved.

The 15th Internatonal Conference Quality in Resarch (Qir) 2017 Preparation and Ionic Conductivity of Li3.9Ca0.1Ti5O12 Using Waste Chicken Eggshells as ca Source for Anode Material of Lithium-Ion Batteries

NASA Astrophysics Data System (ADS)

Subhan, Achmad; Setiawan, Dedy; Ahmiatri Saptari, Sitti

2018-03-01

Li3.9Ca0.1Ti5O12 has been synthesized as anode material for lithium-ion batteries parallel with Li4Ti5O12 anode material using solid state reaction method in an air atmosphere. LiOH.H2O, TiO2, and waste chicken eggshells in the form of CaCO3 were chosen as sources of Li, Ti, and Ca respectively and prepared using stoichiometric. The phase structure, morphology, and electrochemical impedance of as-prepared samples were characterized using XRD, SEM, and EIS. The XRD characterization revealed that in Li3.9Ca0.1Ti5O12 sample, all amount of dopant had entered the lattice structure of Li4Ti5O12. The EDX image also detect the existence of Ca in the structure of Li3.9Ca0.1Ti5O12. The EIS characterization revealed that the Li3.9Ca0.1Ti5O12 sample had lower electrochemical impedance compared to the Li4Ti5O12 sample. The diffusion coefficient were obtained by Faraday’s method, and exhibited that the Li3.9Ca0.1Ti5O12 sample (1.46986 × 10-12 cm2/s) had higher ionic conductivity than the Li4Ti5O12 sample (4.40995 × 10-16 cm2/s). According to the cycle performance test, the Li3.9Ca0.1Ti5O12 sample also had higher charge-discharge capacity and stability compared to the Li4Ti5O12 sample.

Investigation of hydrodynamic behaviour of membranes using radiotracer techniques

NASA Astrophysics Data System (ADS)

Miskiewicz, A.; Zakrzewska-Trznadel, G.

2013-05-01

The aim of the work was to study membrane devices using short-lived radioisotopes like Ba-137m and Ga-68 as tracers. These radioisotopes were obtained from radionuclide generators: Cs-137/Ba-137m and Ge-68/Ga-68. The first radionuclide, namely Ba-137m with a half-life of 2.55 minutes was applied as a liquid phase tracer for studying hydrodynamic conditions inside the membrane apparatus. The membrane module with ceramic membranes was tested by using Ba-137m. The experiments showed that this radionuclide with a short half-life is a perfect tracer for liquid phase, whereas Ga-68 with longer half-life equal to 68 minutes was considered as a solid phase (bentonite) tracer. Ga-68 was used to gain more knowledge about the phenomena occurring in the membrane boundary layer. After kinetic studies of isotope adsorption into the carrier material, the growth rate of the deposit layer as well as deposit's thickness on the flat-sheet membrane were studied. The influence of such process parameters like pressure, linear velocity of liquid and feed concentration on formation of the bentonite layer on the membrane surface was studied.

Effects of breeding habitat (woodland versus urban) and metal pollution on the egg characteristics of great tits (Parus major).

PubMed

Hargitai, Rita; Nagy, Gergely; Nyiri, Zoltán; Bervoets, Lieven; Eke, Zsuzsanna; Eens, Marcel; Török, János

2016-02-15

In an urban environment, birds are exposed to metals, which may accumulate in their tissues and cause oxidative stress. Female birds may eliminate these pollutants through depositing them into eggs, thus eggs become suitable bioindicators of pollution. In this study, we aimed to analyse whether eggshell spotting pattern, egg volume, eggshell thickness and egg yolk antioxidant (lutein, tocopherol, retinol and selenium) levels were related to the breeding area (woodland versus urban) and the metal levels in the eggshell of a small passerine species, the great tit (Parus major). In the urban habitat, soil and eggshells contained higher concentrations of metals, and soil calcium level was also higher than that in the woodland. Eggshell spotting intensity and egg volume did not differ between eggs laid in the woodland and the urban park, and these traits were not related to the metal levels of the eggshell, suggesting that these egg characteristics are not sensitive indicators of metal pollution. A more aggregated eggshell spotting distribution indicated a higher Cu concentration of the eggshell. We found that eggshells were thinner in the less polluted woodland habitat, which is likely due to the limited Ca availability of the woodland area. Great tit eggs laid in the urban environment had lower yolk lutein, retinol and selenium concentrations, however, as a possible compensation for these lower antioxidant levels, urban females deposited more tocopherol into the egg yolk. It appears that females from different breeding habitats may provide similar antioxidant protection for their offspring against oxidative damage by depositing different specific dietary antioxidants. Egg yolk lutein and retinol levels showed a negative relationship with lead concentration of the eggshell, which may suggest that lead had a negative impact on the amount of antioxidants available for embryos during development in great tits. Copyright © 2015 Elsevier B.V. All rights reserved.

Transfer of Dorsoventral and Terminal Information from the Ovary to the Embryo by a Common Group of Eggshell Proteins in Drosophila.

PubMed

Mineo, Alessandro; Furriols, Marc; Casanova, Jordi

2017-04-01

The Drosophila eggshell is an extracellular matrix that confers protection to the egg and also plays a role in transferring positional information from the ovary to pattern the embryo. Among the constituents of the Drosophila eggshell, Nasrat, Polehole, and Closca form a group of proteins related by sequence, secreted by the oocyte, and mutually required for their incorporation into the eggshell. Besides their role in eggshell integrity, Nasrat, Polehole, and Closca are also required for embryonic terminal patterning by anchoring or stabilizing Torso-like at the eggshell. Here, we show that they are also required for dorsoventral patterning, thereby unveiling that the dorsoventral and terminal systems, hitherto considered independent, share a common extracellular step. Furthermore, we show that Nasrat, Polehole, and Closca are required for proper Nudel activity, a protease acting both in embryonic dorsoventral patterning and eggshell integrity, thus providing a means to account for the role of Nasrat, Polehole, and Closca. We propose that a Nasrat/Polehole/Closca complex acts as a multifunctional hub to anchor various proteins synthesized at oogenesis, ensuring their spatial and temporal restricted function. Copyright © 2017 by the Genetics Society of America.

Liquid Metering Centrifuge Sticks (LMCS): A Centrifugal Approach to Metering Known Sample Volumes for Colorimetric Solid Phase Extraction (C-SPE)

NASA Technical Reports Server (NTRS)

Gazda, Daniel B.; Schultz, John R.; Clarke, Mark S.

2007-01-01

Phase separation is one of the most significant obstacles encountered during the development of analytical methods for water quality monitoring in spacecraft environments. Removing air bubbles from water samples prior to analysis is a routine task on earth; however, in the absence of gravity, this routine task becomes extremely difficult. This paper details the development and initial ground testing of liquid metering centrifuge sticks (LMCS), devices designed to collect and meter a known volume of bubble-free water in microgravity. The LMCS uses centrifugal force to eliminate entrapped air and reproducibly meter liquid sample volumes for analysis with Colorimetric Solid Phase Extraction (C-SPE). C-SPE is a sorption-spectrophotometric platform that is being developed as a potential spacecraft water quality monitoring system. C-SPE utilizes solid phase extraction membranes impregnated with analyte-specific colorimetric reagents to concentrate and complex target analytes in spacecraft water samples. The mass of analyte extracted from the water sample is determined using diffuse reflectance (DR) data collected from the membrane surface and an analyte-specific calibration curve. The analyte concentration can then be calculated from the mass of extracted analyte and the volume of the sample analyzed. Previous flight experiments conducted in microgravity conditions aboard the NASA KC-135 aircraft demonstrated that the inability to collect and meter a known volume of water using a syringe was a limiting factor in the accuracy of C-SPE measurements. Herein, results obtained from ground based C-SPE experiments using ionic silver as a test analyte and either the LMCS or syringes for sample metering are compared to evaluate the performance of the LMCS. These results indicate very good agreement between the two sample metering methods and clearly illustrate the potential of utilizing centrifugal forces to achieve phase separation and metering of water samples in microgravity.

Synthesis of Stable Microcapsules from Trematode Eggshell Components.

DTIC Science & Technology

1988-04-29

8217 Arlington, VA 22217-5000 61153N RR4106 71,E ’Include Security Classification) (u) Synthesis of Stable Microcapsules from Trematode Eggshell Components 12...necessary and Identify by block number) 3RO~P SUB-P~iA Microcapsule , Dopa-proteins, trematode, crosslinks, eggshell 79 ABSTRAC7 ,Continue an reverse If...All other editions are obsolete. S ,.O 0 V po r t -A’X I T!L~-r ....7 KIT X - ~.W.:,iili Synthesis of Stable Microcapsules from Trematode Eggshell

Near-ambient solid polymer fuel cell

NASA Technical Reports Server (NTRS)

Holleck, G. L.

1993-01-01

Fuel cells are extremely attractive for extraterrestrial and terrestrial applications because of their high energy conversion efficiency without noise or environmental pollution. Among the various fuel cell systems the advanced polymer electrolyte membrane fuel cells based on sulfonated fluoropolymers (e.g., Nafion) are particularly attractive because they are fairly rugged, solid state, quite conductive, of good chemical and thermal stability and show good oxygen reduction kinetics due to the low specific adsorption of the electrolyte on the platinum catalyst. The objective of this program is to develop a solid polymer fuel cell which can efficiently operate at near ambient temperatures without ancillary components for humidification and/or pressurization of the fuel or oxidant gases. During the Phase 1 effort we fabricated novel integral electrode-membrane structures where the dispersed platinum catalyst is precipitated within the Nafion ionomer. This resulted in electrode-membrane units without interfacial barriers permitting unhindered water diffusion from cathode to anode. The integral electrode-membrane structures were tested as fuel cells operating on H2 and O2 or air at 1 to 2 atm and 10 to 50 C without gas humidification. We demonstrated that cells with completely dry membranes could be self started at room temperature and subsequently operated on dry gas for extended time. Typical room temperature low pressure operation with unoptimized electrodes yielded 100 mA/cm(exp 2) at 0.5V and maximum currents over 300 mA/cm(exp 2) with low platinum loadings. Our results clearly demonstrate that operation of proton exchange membrane fuel cells at ambient conditions is feasible. Optimization of the electrode-membrane structure is necessary to assess the full performance potential but we expect significant gains in weight and volume power density for the system. The reduced complexity will make fuel cells also attractive for smaller and portable power supplies and as replacement for batteries.

Nature’s Palette: Characterization of Shared Pigments in Colorful Avian and Mollusk Shells

PubMed Central

Brennan, Patricia L. R.; Hanley, Daniel; Grim, Tomáš; Hauber, Mark E.; Holford, Mandë

2015-01-01

Pigment-based coloration is a common trait found in a variety of organisms across the tree of life. For example, calcareous avian eggs are natural structures that vary greatly in color, yet just a handful of tetrapyrrole pigment compounds are responsible for generating this myriad of colors. To fully understand the diversity and constraints shaping nature’s palette, it is imperative to characterize the similarities and differences in the types of compounds involved in color production across diverse lineages. Pigment composition was investigated in eggshells of eleven paleognath bird taxa, covering several extinct and extant lineages, and shells of four extant species of mollusks. Birds and mollusks are two distantly related, calcareous shell-building groups, thus characterization of pigments in their calcareous structures would provide insights to whether similar compounds are found in different phyla (Chordata and Mollusca). An ethylenediaminetetraacetic acid (EDTA) extraction protocol was used to analyze the presence and concentration of biliverdin and protoporphyrin, two known and ubiquitous tetrapyrrole avian eggshell pigments, in all avian and molluscan samples. Biliverdin was solely detected in birds, including the colorful eggshells of four tinamou species. In contrast, protoporphyrin was detected in both the eggshells of several avian species and in the shells of all mollusks. These findings support previous hypotheses about the ubiquitous deposition of tetrapyrroles in the eggshells of various bird lineages and provide evidence for its presence also across distantly related animal taxa. PMID:26650398

Ionogels, ionic liquid based hybrid materials.

PubMed

Le Bideau, Jean; Viau, Lydie; Vioux, André

2011-02-01

The current interest in ionic liquids (ILs) is motivated by some unique properties, such as negligible vapour pressure, thermal stability and non-flammability, combined with high ionic conductivity and wide electrochemical stability window. However, for material applications, there is a challenging need for immobilizing ILs in solid devices, while keeping their specific properties. In this critical review, ionogels are presented as a new class of hybrid materials, in which the properties of the IL are hybridized with those of another component, which may be organic (low molecular weight gelator, (bio)polymer), inorganic (e.g. carbon nanotubes, silica etc.) or hybrid organic-inorganic (e.g. polymer and inorganic fillers). Actually, ILs act as structuring media during the formation of inorganic ionogels, their intrinsic organization and physicochemical properties influencing the building of the solid host network. Conversely, some effects of confinement can modify some properties of the guest IL, even though liquid-like dynamics and ion mobility are preserved. Ionogels, which keep the main properties of ILs except outflow, while allowing easy shaping, considerably enlarge the array of applications of ILs. Thus, they form a promising family of solid electrolyte membranes, which gives access to all-solid devices, a topical industrial challenge in domains such as lithium batteries, fuel cells and dye-sensitized solar cells. Replacing conventional media, organic solvents in lithium batteries or water in proton-exchange-membrane fuel cells (PEMFC), by low-vapour-pressure and non flammable ILs presents major advantages such as improved safety and a higher operating temperature range. Implementation of ILs in separation techniques, where they benefit from huge advantages as well, relies again on the development of supported IL membranes such as ionogels. Moreover, functionalization of ionogels can be achieved both by incorporation of organic functions in the solid matrix, and by encapsulation of molecular species (from metal complexes to enzymes) in the immobilized IL phase, which opens new routes for designing advanced materials, especially (bio)catalytic membranes, sensors and drug release systems (194 references).

Salmonella enterica isolates from layer farm environments are able to form biofilm on eggshell surfaces.

PubMed

Pande, Vivek V; McWhorter, Andrea R; Chousalkar, Kapil K

2016-08-01

This study examined the eggshell biofilm forming ability of Salmonella enterica isolates recovered from egg farms. Multicellular behaviour and biofilm production were examined at 22 and 37°C by Congo red morphology and the crystal violet staining assay. The results indicated that the biofilm forming behaviour of Salmonella isolates was dependent on temperature and associated with serovars. Significantly greater biofilm production was observed at 22°C compared with 37°C. The number of viable biofilm cells attached to eggshells after incubation for 48 h at 22°C was significantly influenced by serovar. Scanning electron microscopic examination revealed firm attachment of bacterial cells to the eggshell surface. The relative expression of csgD and adrA gene was significantly higher in eggshell biofilm cells of S. Mbandaka and S. Oranienburg. These findings demonstrate that Salmonella isolates are capable of forming biofilm on the eggshell surface and that this behaviour is influenced by temperature and serovar.

Micro-CT scan reveals an unexpected high-volume and interconnected pore network in a Cretaceous Sanagasta dinosaur eggshell.

PubMed

Hechenleitner, E Martín; Grellet-Tinner, Gerald; Foley, Matthew; Fiorelli, Lucas E; Thompson, Michael B

2016-03-01

The Cretaceous Sanagasta neosauropod nesting site (La Rioja, Argentina) was the first confirmed instance of extinct dinosaurs using geothermal-generated heat to incubate their eggs. The nesting strategy and hydrothermal activities at this site led to the conclusion that the surprisingly 7 mm thick-shelled eggs were adapted to harsh hydrothermal microenvironments. We used micro-CT scans in this study to obtain the first three-dimensional microcharacterization of these eggshells. Micro-CT-based analyses provide a robust assessment of gas conductance in fossil dinosaur eggshells with complex pore canal systems, allowing calculation, for the first time, of the shell conductance through its thickness. This novel approach suggests that the shell conductance could have risen during incubation to seven times more than previously estimated as the eggshell erodes. In addition, micro-CT observations reveal that the constant widening and branching of pore canals form a complex funnel-like pore canal system. Furthermore, the high density of pore canals and the presence of a lateral canal network in the shell reduce the risks of pore obstruction during the extended incubation of these eggs in a relatively highly humid and muddy nesting environment. © 2016 The Author(s).

Synthesis of polyetherimide / halloysite nanotubes (PEI/HNTs) based nanocomposite membrane towards hydrogen storage

NASA Astrophysics Data System (ADS)

Muthu, R. Naresh; Rajashabala, S.; Kannan, R.

2018-04-01

Even though hydrogen is considered as green and clean energy sources of future, the blooming of hydrogen economy mainly relies on the development of safe and efficient hydrogen storage medium. The present work is aimed at the synthesis and characterization of polyetherimide/acid treated halloysite nanotubes (PEI/A-HNTs) nanocomposite membranes for solid state hydrogen storage medium, where phase inversion technique was adopted for the synthesis of nanocomposite membrane. The synthesized PEI/A-HNTs nanocomposite membranes were characterized by XRD, FTIR, SEM, EDX, CHNS elemental analysis and TGA. Hydrogenation studies were performed using a Sievert's-like hydrogenation setup. The important conclusions arrived from the present work are the PEI/A-HNTs nanocomposite membranes have better performance with a maximum hydrogen storage capacity of 3.6 wt% at 100 °C than pristine PEI. The adsorbed hydrogen possesses the average binding energy of 0.31 eV which lies in the recommended range of US- DOE 2020 targets. Hence it is expected that the PEI/A-HNTs nanocomposite membranes may have bright extent in the scenario of hydrogen fuel cell applications.

Integrating transcriptome and genome re-sequencing data to identify key genes and mutations affecting chicken eggshell qualities.

PubMed

Zhang, Quan; Zhu, Feng; Liu, Long; Zheng, Chuan Wei; Wang, De He; Hou, Zhuo Cheng; Ning, Zhong Hua

2015-01-01

Eggshell damages lead to economic losses in the egg production industry and are a threat to human health. We examined 49-wk-old Rhode Island White hens (Gallus gallus) that laid eggs having shells with significantly different strengths and thicknesses. We used HiSeq 2000 (Illumina) sequencing to characterize the chicken transcriptome and whole genome to identify the key genes and genetic mutations associated with eggshell calcification. We identified a total of 14,234 genes expressed in the chicken uterus, representing 89% of all annotated chicken genes. A total of 889 differentially expressed genes were identified by comparing low eggshell strength (LES) and normal eggshell strength (NES) genomes. The DEGs are enriched in calcification-related processes, including calcium ion transport and calcium signaling pathways as revealed by gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis. Some important matrix proteins, such as OC-116, LTF and SPP1, were also expressed differentially between two groups. A total of 3,671,919 single-nucleotide polymorphisms (SNPs) and 508,035 Indels were detected in protein coding genes by whole-genome re-sequencing, including 1775 non-synonymous variations and 19 frame-shift Indels in DEGs. SNPs and Indels found in this study could be further investigated for eggshell traits. This is the first report to integrate the transcriptome and genome re-sequencing to target the genetic variations which decreased the eggshell qualities. These findings further advance our understanding of eggshell calcification in the chicken uterus.

Glasslike Membrane Protein Diffusion in a Crowded Membrane.

PubMed

Munguira, Ignacio; Casuso, Ignacio; Takahashi, Hirohide; Rico, Felix; Miyagi, Atsushi; Chami, Mohamed; Scheuring, Simon

2016-02-23

Many functions of the plasma membrane depend critically on its structure and dynamics. Observation of anomalous diffusion in vivo and in vitro using fluorescence microscopy and single particle tracking has advanced our concept of the membrane from a homogeneous fluid bilayer with freely diffusing proteins to a highly organized crowded and clustered mosaic of lipids and proteins. Unfortunately, anomalous diffusion could not be related to local molecular details given the lack of direct and unlabeled molecular observation capabilities. Here, we use high-speed atomic force microscopy and a novel analysis methodology to analyze the pore forming protein lysenin in a highly crowded environment and document coexistence of several diffusion regimes within one membrane. We show the formation of local glassy phases, where proteins are trapped in neighbor-formed cages for time scales up to 10 s, which had not been previously experimentally reported for biological membranes. Furthermore, around solid-like patches and immobile molecules a slower glass phase is detected leading to protein trapping and creating a perimeter of decreased membrane diffusion.

Solid state proton and electron mediating membrane and use in catalytic membrane reactors

DOEpatents

White, J.H.; Schwartz, M.; Sammells, A.F.

1998-10-13

This invention provides catalytic proton and electron mediating membranes useful in catalytic reactors. The membranes have an oxidation and a reduction surface and comprise a single-phase mixed metal oxide material of the formula: AB{sub 1{minus}x}B{prime}{sub x}O{sub 3{minus}y} wherein A is selected from Ca, Sr or Ba ions; B is selected from Ce, Tb, Pr, or Th ions; B{prime} is selected from Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Al, Ga, or In ions, or combinations thereof; and x is greater than or equal to 0.02 and less than or equal to 0.5. The membranes can further comprise a catalyst on either the oxidation or reduction surface, or both. Membranes include those which are fabricated by combining powders of metal oxides or metal carbonates of metal A ion, metal B ion and metal B{prime} ion such that the stoichiometric ratio A:B:B{prime} is 1:1{minus}x:x where 0.2{<=}{times}0.5, repeatedly calcining and milling the combined powders until a single-phase material is obtained and pressing and sintering the single phase material to obtain a membrane. 6 figs.

Characterization of a supported ionic liquid membrane used for the removal of cyanide from wastewater.

PubMed

Xue, Juan Qin; Liu, Ni Na; Li, Guo Ping; Dang, Long Tao

2017-12-01

This work evaluated the performance of ionic liquids (ILs) in supported liquid membranes in the removal of total cyanide from wastewater. Membranes were characterized by scanning electron microscopy and contact angle measurements to study the membrane morphology and wetting ability. In particular, the effects of operational parameters such as membrane immersion time, feed-phase concentration, and pH on cyanide removal were investigated. ILs are organic salts that are entirely composed of organic cations and either organic or inorganic anions. Since their vapor pressure is negligible, they can be handled easily; this characteristic gives rise to their 'green' nature. In this study, a hydrophobic IL, 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim]PF 6 ), was immobilized in the pores of a solid polymeric support made of polyvinylidene fluoride. The optimal conditions were as follows: 1 hour membrane immersion time, 312.24 mg/L feed-phase concentration, a feed-phase pH of 4, 3% NaOH solution, and 1 hour stirring time. The cyanide removal was 95.31%. The treatment of cyanide using supported ionic liquid membrane (SILM) technology is a method with potential applications in industry.

SSM-based electrophysiology.

PubMed

Schulz, Patrick; Garcia-Celma, Juan J; Fendler, Klaus

2008-10-01

An assay technique for the electrical characterization of electrogenic transport proteins on solid supported membranes is presented. Membrane vesicles, proteoliposomes or membrane fragments containing the transporter are adsorbed to the solid supported membrane and are activated by providing a substrate or a ligand via a rapid solution exchange. This technique opens up new possibilities where conventional electrophysiology fails like transporters or ion channels from bacteria and from intracellular compartments. Its rugged design and potential for automation make it suitable for drug screening.

Ammonia Monitor

NASA Technical Reports Server (NTRS)

Sauer, Richard L. (Inventor); Akse, James R. (Inventor); Thompson, John O. (Inventor); Atwater, James E. (Inventor)

1999-01-01

Ammonia monitor and method of use are disclosed. A continuous, real-time determination of the concentration of ammonia in an aqueous process stream is possible over a wide dynamic range of concentrations. No reagents are required because pH is controlled by an in-line solid-phase base. Ammonia is selectively transported across a membrane from the process stream to an analytical stream to an analytical stream under pH control. The specific electrical conductance of the analytical stream is measured and used to determine the concentration of ammonia.

Large-scale geographical variation in eggshell metal and calcium content in a passerine bird (Ficedula hypoleuca).

PubMed

Ruuskanen, Suvi; Laaksonen, Toni; Morales, Judith; Moreno, Juan; Mateo, Rafael; Belskii, Eugen; Bushuev, Andrey; Järvinen, Antero; Kerimov, Anvar; Krams, Indrikis; Morosinotto, Chiara; Mänd, Raivo; Orell, Markku; Qvarnström, Anna; Slate, Fred; Tilgar, Vallo; Visser, Marcel E; Winkel, Wolfgang; Zang, Herwig; Eeva, Tapio

2014-03-01

Birds have been used as bioindicators of pollution, such as toxic metals. Levels of pollutants in eggs are especially interesting, as developing birds are more sensitive to detrimental effects of pollutants than adults. Only very few studies have monitored intraspecific, large-scale variation in metal pollution across a species' breeding range. We studied large-scale geographic variation in metal levels in the eggs of a small passerine, the pied flycatcher (Ficedula hypoleuca), sampled from 15 populations across Europe. We measured 10 eggshell elements (As, Cd, Cr, Cu, Ni, Pb, Zn, Se, Sr, and Ca) and several shell characteristics (mass, thickness, porosity, and color). We found significant variation among populations in eggshell metal levels for all metals except copper. Eggshell lead, zinc, and chromium levels decreased from central Europe to the north, in line with the gradient in pollution levels over Europe, thus suggesting that eggshell can be used as an indicator of pollution levels. Eggshell lead levels were also correlated with soil lead levels and pH. Most of the metals were not correlated with eggshell characteristics, with the exception of shell mass, or with breeding success, which may suggest that birds can cope well with the current background exposure levels across Europe.

Solid-State Water Electrolysis with an Alkaline Membrane

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

Leng, YJ; Chen, G; Mendoza, AJ

2012-06-06

We report high-performance, durable alkaline membrane water electrolysis in a solid-state cell. An anion exchange membrane (AEM) and catalyst layer ionomer for hydroxide ion conduction were used without the addition of liquid electrolyte. At 50 degrees C, an AEM electrolysis cell using iridium oxide as the anode catalyst and Pt black as the cathode catalyst exhibited a current density of 399 mA/cm(2) at 1.80 V. We found that the durability of the AEM-based electrolysis cell could be improved by incorporating a highly durable ionomer in the catalyst layer and optimizing the water feed configuration. We demonstrated an AEM-based electrolysis cellmore » with a lifetime of > 535 h. These first-time results of water electrolysis in a solid-state membrane cell are promising for low-cost, scalable hydrogen production.« less

Materiais a base de oxidos com estrutura do tipo perovskite e compositos como anodos de PCES: Propriedades Funcionais e Comportamento Eletroquimico em Celulas com Eletrolitos Solidos a Base de Galatos e Silicatos

NASA Astrophysics Data System (ADS)

Kolotygin, Vladislav

This work was focused on the analysis of transport, thermomechanical and electrochemical properties of a series of perovskite-like oxide materials and composites for potential applications as anodes of intermediate-temperature solid oxide fuel cells (SOFCs) with lanthanum gallate and silicate solid electrolytes. The primary attention was centered on A(Mn,Nb)O3-delta (A = Sr, Ca) and (La,Sr)(Mn,Ti)O3-based systems, lanthanum chromite substituted with acceptor-type and variable-valence cations, and various Ni-containing cermets. Emphasis was given to phase stability of the materials, their crystal structure, microstructure of porous electrode layers and dense ceramics, electronic conductivity, Seebeck coefficient, oxygen permeability, thermal and chemical induced expansion, and anodic overpotentials of the electrodes deposited onto (La,Sr)(Ga,Mg)O3- and La10(Si,Al)6O27-based electrolyte membranes. In selected cases, roles of oxygen diffusivity, states of the transition metal cations relevant for the electronic transport, catalytically active additives and doped ceria protective interlayers introduced in the model electrochemical cells were assessed. The correlations between transport properties of the electrode materials and electrochemical behavior of porous electrodes showed that the principal factors governing anode performance include, in particular, electronic conduction of the anode compositions and cation interdiffusion between the electrodes and solid electrolytes. The latter is critically important for the silicatebased electrolyte membranes, leading to substantially worse anode properties compared to the electrochemical cells with lanthanum gallate solid electrolyte. The results made it possible to select several anode compositions exhibiting lower area-specific electrode resistivity compared to known analogues, such as (La,Sr)(Cr,Mn)O3-delta.

Effects of dietary supplementation of arginine-silicate-inositol complex on absorption and metabolism of calcium of laying hens

PubMed Central

Orhan, Cemal; Tuzcu, Mehmet; Hayirli, Armagan; Komorowski, James R.; Sahin, Nurhan

2018-01-01

The effects of supplementation of arginine-silicate-inositol complex (ASI; 49.5–8.2–25 g/kg, respectively) to laying hens were investigated with respect to eggshell quality, calcium (Ca) balance, and expression of duodenal proteins related to Ca metabolism (calbindin and tight junction proteins). A total of 360 laying hens, 25 weeks old, were divided into 3 groups consisting of 6 replicate of cages, 20 birds per cage. The groups were fed a basal diet and the basal diet supplemented with 500 or 1000 mg ASI complex per kilogram for 90 days. Data were analyzed by ANCOVA using data during the first week of the adaptation period as covariates. As the ASI complex supplementation level increased, there were increases in feed intake (P < 0.0001), egg production (P < 0.001), egg weight (P < 0.0001) and eggshell weight (P < 0.001) weight, and shell thickness (P < 0.001) and decreases in feed conversion ratio and cracked egg percentage (P < 0.0001 for both). Concentrations of serum osteocalcin (P < 0.0001), vitamin D (P < 0.0001), calcium (P < 0.001), phosphorus (P < 0.001), and alkaline phosphatase (P < 0.008) as well as amounts of calcium retention (P < 0.0001) and eggshell calcium deposition (P < 0.001), and Ca balance (P < 0.0001) increased, whereas amount of calcium excretion (P < 0.001) decreased linearly in a dose-dependent manner. The ASI complex supplementation increased expressions of calcium transporters (calbindin-D28k, N sodium-calcium exchanger, plasma membrane calcium ATPase, and vitamin D receptor) and tight junction proteins (zonula occludens-1 and occludin) in the duodenum in a linear fashion (P < 0.0001 for all). In conclusion, provision of dietary ASI complex to laying hens during the peak laying period improved eggshell quality through improving calcium utilization as reflected by upregulation of genes related to the calcium metabolism. Further studies are needed to elucidate the contribution of each of the ASI complex ingredients. PMID:29360830

Quaternary record of aridity and mean annual precipitation based on δ15N in ratite and dromornithid eggshells from Lake Eyre, Australia.

PubMed

Newsome, Seth D; Miller, Gifford H; Magee, John W; Fogel, Marilyn L

2011-12-01

The cause(s) of the late Pleistocene megafauna extinction on the Australian continent remains largely unresolved. Unraveling climatic forcing mechanisms from direct or indirect human agents of ecosystem alteration has proven to be extremely difficult in Australia due to the lack of (1) well-dated vertebrate fossils and (2) paleo-environmental and -ecological records spanning the past approximately 100 ka when regional climatic conditions are known to have significantly varied. We have examined the nitrogen isotope composition (δ(15)N) of modern emu (Dromaius novaehollandiae) eggshells collected along a precipitation gradient in Australia, along with modern climatological data and dietary δ(15)N values. We then used modern patterns to interpret an approximately 130-ka record of δ(15)N values in extant Dromaius and extinct Genyornis newtoni eggshells from Lake Eyre to obtain a novel mean annual precipitation (MAP) record for central Australia spanning the extinction interval. Our data also provide the first detailed information on the trophic ecology and environmental preferences of two closely related taxa, one extant and one extinct. Dromaius eggshell δ(15)N values show a significant shift to higher values during the Last Glacial Maximum and Holocene, which we interpret to indicate more frequent arid conditions (<200 mm MAP), relative to δ(15)N from samples just prior to the megafauna extinction. Genyornis eggshells had δ(15)N values reflecting wetter nesting conditions overall relative to those of coeval Dromaius, perhaps indicating that Genyornis was more reliant on mesic conditions. Lastly, the Dromaius eggshell record shows a significant decrease in δ(13)C values prior to the extinction, whereas the Genyornis record does not. Neither species showed a concomitant change in δ(15)N prior to the extinction, which suggests that a significant change in vegetation surrounding Lake Eyre occurred prior to an increase in local aridity.

UV-visible spectroscopic estimation of photodegradation of rhodamine-B dye using tin(IV) oxide nanoparticles.

PubMed

Sangami, G; Dharmaraj, N

2012-11-01

Nanocrystalline, tin(IV) oxide (SnO(2)) particles has been prepared by thermal decomposition of tin oxalate precursor obtained from the reactions of tin(IV) chloride and sodium oxalate using eggshell membrane (ESM). The as-prepared SnO(2) nanoparticles were characterized by thermal studies, transmission electron microscopy (TEM), powder X-ray diffraction (XRD), Raman, FT-IR and UV-visible studies and used as a photocatalyst for the degradation of rhodamine-B (Rh-B) dye. The size of the prepared nanoparticles was in the range of 5-12nm as identified from the TEM images. Powder XRD data revealed the presence of a tetragonal, rutile crystalline phase of the tin(IV) oxide nanoparticles. Thermal analysis showed that the decomposition of tin oxalate precursor to yield the titled tin(IV) oxide nanoparticles was completed below 500°C. The extent of degradation of Rh-B in the presence of SnO(2) monitored by absorption spectral measurements demonstrated that 94.48% of the selected dye was degraded upon irradiation with UV light for 60 min. Copyright © 2012 Elsevier B.V. All rights reserved.

Regional and interspecific variation in Sr, Ca, and Sr/Ca ratios in avian eggshells from the USA.

PubMed

Mora, Miguel A; Brattin, Bryan; Baxter, Catherine; Rivers, James W

2011-08-01

To examine regional variation in strontium (Sr), which at high concentrations may reduce eggshell quality, increase egg breakage and reproductive failure, we analyzed Sr, and calcium (Ca) concentrations and Sr/Ca ratios in eggshells from 20 avian species from California, Texas, Idaho, Kansas, and Michigan. In addition, we included data previously reported from Arizona to expand the regional comparisons and to better establish patterns of Sr, and Sr/Ca ratios in bird species across the United States. We found Sr concentrations varied significantly among regions, among species, and among foraging guilds; this variability is strongly influenced by the Sr/Ca ratios in surface water from locations close to the region where the eggshells were collected. Sr concentrations and Sr/Ca ratios were significantly higher in bird eggshells from the Volta wildlife region in the San Joaquin Valley, California and in various locales from Arizona. Sr concentrations and Sr/Ca ratios in bird eggshells from other locations in the USA were lower than those detected in these two regions. Among foraging guilds, invertivores had the highest Sr concentrations and Sr/Ca ratios and carnivores had the lowest. In general, the Sr/Ca ratio increased strongly with increasing Sr concentrations (R(2) = 0.99, P < 0.0001). There was a significant correlation (R(2) = 0.58, P < 0.0001) between Sr/Ca ratios in water and the average Sr/Ca ratios in eggshells suggesting that these values could be determined from Sr/Ca ratios in water. Eggshell thickness was poorly correlated with Sr (R(2) = 0.03) but had a significant and positive correlation with Ca and was more properly correlated by a quadratic equation (R(2) = 0.50, Thickness = 2.13 - 0.02Ca - 3.07 * 10(-5)Ca(2)). Our study provides further evidence that Sr accumulates significantly in the avian eggshell, in some regions at concentrations which could be of concern for potential negative effects on reproduction. We suggest that when assessing the effects of metals on avian reproduction in regions with high Sr deposits in rock and soil, Sr concentrations in the eggshell also should be measured to evaluate additional effects on thickness and reproduction.

Rod/Coil Block Copolyimides for Ion-Conducting Membranes

NASA Technical Reports Server (NTRS)

Meador, Mary Ann B.; Kinder, James D.

2003-01-01

Rod/coil block copolyimides that exhibit high levels of ionic conduction can be made into diverse products, including dimensionally stable solid electrolyte membranes that function well over wide temperature ranges in fuel cells and in lithium-ion electrochemical cells. These rod/coil block copolyimides were invented to overcome the limitations of polymers now used to make such membranes. They could also be useful in other electrochemical and perhaps some optical applications, as described below. The membranes of amorphous polyethylene oxide (PEO) now used in lithium-ion cells have acceptably large ionic conductivities only at temperatures above 60 C, precluding use in what would otherwise be many potential applications at lower temperatures. PEO is difficult to process, and, except at the highest molecular weights it is not very dimensionally stable. It would be desirable to operate fuel cells at temperatures above 80 C to take advantage of better kinetics of redox reactions and to reduce contamination of catalysts. Unfortunately, proton-conduction performance of a typical perfluorosulfonic polymer membrane now used as a solid electrolyte in a fuel cell decreases with increasing temperature above 80 C because of loss of water from within the membrane. The loss of water has been attributed to the hydrophobic nature of the polymer backbone. In addition, perfluorosulfonic polymers are expensive and are not sufficiently stable for long-term use. Rod/coil block copolyimides are so named because each molecule of such a polymer comprises short polyimide rod segments alternating with flexible polyether coil segments (see figure). The rods and coils can be linear, branched, or mixtures of linear and branched. A unique feature of these polymers is that the rods and coils are highly incompatible, giving rise to a phase separation with a high degree of ordering that creates nanoscale channels in which ions can travel freely. The conduction of ions can occur in the coil phase, the rod phase, or both phases.

Relationship between fabrication method and chemical stability of Ni-BaZr0.8Y0.2O3-δ membrane

NASA Astrophysics Data System (ADS)

Fang, Shumin; Wang, Siwei; Brinkman, Kyle S.; Su, Qing; Wang, Haiyan; Chen, Fanglin

2015-03-01

NiO effectively promotes the sintering of highly refractory Y-doped BaZrO3 (BZY) through the formation of BaY2NiO5, providing a simple and cost-effective method for the fabrication of dense BZY electrolyte and Ni-BZY hydrogen separation membrane at ∼1400 °C. Unfortunately, insulating BaCO3 and Y2O3 phases formed on the surface of BZY and Ni-BZY prepared by solid state reaction method with NiO after annealing in wet CO2. Ni-BZY membranes prepared from different methods suffered different degree of performance loss in wet H2 at 900 °C. The chemical instability of Ni-BZY is attributed to the formation of a secondary phase (BaY2O4) generated from the reduction of BaY2NiO5 in H2 during the sintering process. Both BaY2O4 and BaY2NiO5 react with H2O, and CO2 at elevated temperatures, generating insulating Ba(OH)2 and BaCO3 phases, respectively. The less BaY2O4 is formed in the fabrication process, the better chemical stability the Ni-BZY membranes possess. Therefore, a new Ni-BZY membrane is prepared through a judicial combination of BZY powders prepared from combined EDTA-citric and solid state reaction methods, and demonstrates exceptional chemical stability in H2O and CO2, enabling stable and even improved hydrogen flux in wet 50% CO2 at 900 °C.

Integrating Transcriptome and Genome Re-Sequencing Data to Identify Key Genes and Mutations Affecting Chicken Eggshell Qualities

PubMed Central

Liu, Long; Zheng, Chuan Wei; Wang, De He; Hou, Zhuo Cheng; Ning, Zhong Hua

2015-01-01

Eggshell damages lead to economic losses in the egg production industry and are a threat to human health. We examined 49-wk-old Rhode Island White hens (Gallus gallus) that laid eggs having shells with significantly different strengths and thicknesses. We used HiSeq 2000 (Illumina) sequencing to characterize the chicken transcriptome and whole genome to identify the key genes and genetic mutations associated with eggshell calcification. We identified a total of 14,234 genes expressed in the chicken uterus, representing 89% of all annotated chicken genes. A total of 889 differentially expressed genes were identified by comparing low eggshell strength (LES) and normal eggshell strength (NES) genomes. The DEGs are enriched in calcification-related processes, including calcium ion transport and calcium signaling pathways as reveled by gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis. Some important matrix proteins, such as OC-116, LTF and SPP1, were also expressed differentially between two groups. A total of 3,671,919 single-nucleotide polymorphisms (SNPs) and 508,035 Indels were detected in protein coding genes by whole-genome re-sequencing, including 1775 non-synonymous variations and 19 frame-shift Indels in DEGs. SNPs and Indels found in this study could be further investigated for eggshell traits. This is the first report to integrate the transcriptome and genome re-sequencing to target the genetic variations which decreased the eggshell qualities. These findings further advance our understanding of eggshell calcification in the chicken uterus. PMID:25974068

EFFECT OF SOLID MEDIUM DURING COOLED STORAGE ON STALLION SPERM PARAMETERS.

PubMed

Santos, F C; Corcini, C D; Costa, V G; Gheller, S M; Nogueira, C E; da Rosa Curcio, B; Varel, A S

2015-01-01

Solid storage medium prevents cellular sedimentation, reduces metabolic demand via limiting movement, and avoids the modification of an extender composition in the sedimentary microenvironment. It has been proven to prolong spermatozoa viability in mammalians. This experiment aims to evaluate the effect of cool storage in solid phase extender on stallion sperms. Semen was collected from 10 Crioulo stallions (n=30) and submitted to treatments: control group (semen extender) and groups with gelatin addition in different concentrations (semen extender + 1%, 2% and 3%). Seminal analyses included motility, mitochondrial functionality, plasma membrane integrity, DNA and acrosome at 0; 24; 48 and 72 hours during cooled storage at 5 degree C. Motility, mitochondrial functionality, plasma membrane and acrosome integrity declined during storage time, with no statistical difference between treatments. DNA integrity did not significantly change during storage period. Solid medium was not harmful and did not improved stallion sperm parameters during cooled storage.

Impact of egg holding temperatures on the recovery of Salmonella from eggshells and stainless steel coupons

USDA-ARS?s Scientific Manuscript database

This experiment was conducted to determine the impact of egg holding temperature on the ability to recover Salmonella from eggshells after 24 h. Salmonella enterica Enteritidis (nalidixic acid resistant marker strain) inoculated eggshells and stainless steel coupons (SSC, 14 mm diameter) were held a...

Incubation reduces microbial growth on eggshells and the opportunity for trans-shell infection.

Treesearch

Mark I. Cook; Steven R. Beissinger; Gary A. Toranzos; Wayne J. Arendt

2005-01-01

Avian eggshells harbour microbes shortly after laying, and under appropriate ambient conditions they can multiply rapidly, penetrate through shell pores, infect egg contents and cause embryo mortality. We experimentally examined how incubation affects bacterial processes on the eggshells of pearl-eyed thrashers Margarops fuscatus nesting in tropical montane and lowland...

The Genyornis Egg: Response to Miller et al.'s commentary on Grellet-Tinner et al., 2016

NASA Astrophysics Data System (ADS)

Grellet-Tinner, Gerald; Spooner, Nigel A.; Handley, Warren D.; Worthy, Trevor H.

2017-04-01

Williams (1981) and Williams and Rich (1991) attributed Australian Quaternary fossil eggshell that differed from that of emu Dromaius novaehollandiae to the extinct bird Genyornis newtoni without any osteological or embryonic support. Such association by proximity or abundance mirrors the case of the mistaken association of oviraptor eggs to Protoceratops in the 1920's by Andrews (Grellet-Tinner and Makovicky, 2006). No other candidate species was considered, and this attribution has been unchallenged and followed by everyone thereafter. Much research has been done on this Australian eggshell, with one result being that the extinction of the parent of this eggshell is the most well documented for a taxon in Australia (e.g., Miller et al., 1999, 2005). Grellet-Tinner et al. (2016) raised several problems with the identity of the eggshell Williams (1981) attributed to Genyornis newtoni and suggested that extinct megapodes of the genus Progura were the more likely layer of this eggshell type, therein referred to as ;putative Genyornis oological material; (PGOM). Miller et al. (2017) challenged our hypothesis stating that ;Based on the dimensions of the reconstructed Spooner Egg,Grellet-Tinner et al. (2016)argue that PGOM is too small for a bird with the body mass estimated for Genyornis (168-275 kg) … …[and] …. None of the additional PGOM observations reported byGrellet-Tinner et al. (2016)are inconsistent with a Genyornis parent;. Here we take the opportunity to respond to their critique, the basis of which resolves into a few points, which we address in turn.

Nanoporous Membranes with Chemically-Tailored Pore Walls from Triblock Terpolymer Templates

NASA Astrophysics Data System (ADS)

Mulvenna, Ryan; Weidman, Jacob; Pople, John; Boudouris, Bryan; Phillip, William

2014-03-01

Membranes generated from self-assembled block polymers have shown promise as highly permeable and selective filters; however, current syntheses of such materials lack diverse pore wall chemical functionality. Here, we report the facile synthesis of polyisoprene- b-polystyrene- b-poly(N , N -dimethylacrylamide) (PI-PS-PDMA) using a controlled reversible addition-fragmentation chain transfer (RAFT) polymerization mechanism to yield a macromolecule with an easily-tunable molecular weight and a narrow molecular weight distribution. The PI-PS-PDMA is then cast into an anisotropic membrane using the self-assembly and non-solvent induced phase separation process (SNIPS) protocol. These membranes can be used in size-selective separations for particles as small as 8 nm in diameter. Furthermore, the PDMA block can be converted to poly(acrylic acid) (PAA) readily in the solid state, and this PI-PS-PAA terpolymer membrane can separate particles as low as 2 nm in diameter while still retaining a relatively high flux. This is the smallest reported separation for a block polymer-based membrane to date. Additionally, the PAA-lined pores serve as a conversion platform to be tuned to any other pore chemistry, which allows the membrane to be of great utility in optimizing chemistry-specific separations.

Molecular preservation in Late Cretaceous sauropod dinosaur eggshells.

PubMed

Schweitzer, M H; Chiappe, L; Garrido, A C; Lowenstein, J M; Pincus, S H

2005-04-22

Exceptionally preserved sauropod eggshells discovered in Upper Cretaceous (Campanian) deposits in Patagonia, Argentina, contain skeletal remains and soft tissues of embryonic Titanosaurid dinosaurs. To preserve these labile embryonic remains, the rate of mineral precipitation must have superseded post-mortem degradative processes, resulting in virtually instantaneous mineralization of soft tissues. If so, mineralization may also have been rapid enough to retain fragments of original biomolecules in these specimens. To investigate preservation of biomolecular compounds in these well-preserved sauropod dinosaur eggshells, we applied multiple analytical techniques. Results demonstrate organic compounds and antigenic structures similar to those found in extant eggshells.

Molecular preservation in Late Cretaceous sauropod dinosaur eggshells

PubMed Central

Schweitzer, M.H; Chiappe, L; Garrido, A.C; Lowenstein, J.M; Pincus, S.H

2005-01-01

Exceptionally preserved sauropod eggshells discovered in Upper Cretaceous (Campanian) deposits in Patagonia, Argentina, contain skeletal remains and soft tissues of embryonic Titanosaurid dinosaurs. To preserve these labile embryonic remains, the rate of mineral precipitation must have superseded post-mortem degradative processes, resulting in virtually instantaneous mineralization of soft tissues. If so, mineralization may also have been rapid enough to retain fragments of original biomolecules in these specimens. To investigate preservation of biomolecular compounds in these well-preserved sauropod dinosaur eggshells, we applied multiple analytical techniques. Results demonstrate organic compounds and antigenic structures similar to those found in extant eggshells. PMID:15888409

A multiplexed three-dimensional paper-based electrochemical impedance device for simultaneous label-free affinity sensing of total and glycated haemoglobin: The potential of using a specific single-frequency value for analysis.

PubMed

Boonyasit, Yuwadee; Chailapakul, Orawon; Laiwattanapaisal, Wanida

2016-09-14

A novel three-dimensional paper-based electrochemical impedance device (3D-PEID) is first introduced for measuring multiple diabetes markers. Herein, a simple 3D-PEID composed of a dual screen-printed electrode on wax-patterned paper coupled with a multilayer of magnetic paper was fabricated for label-free electrochemical detection. The results clearly demonstrated in a step-wise manner that the haptoglobin (Hp)-modified and 3-aminophenylboronic acid (APBA)-modified eggshell membranes (ESMs) were highly responsive to a clinically relevant range of total (0.5-20 g dL(-1); r(2) = 0.989) and glycated haemoglobin (HbA1c) (2.3%-14%; r(2) = 0.997) levels with detection limits (S/N = 3) of 0.08 g dL(-1) and 0.21%, respectively. The optimal binding frequencies of total haemoglobin and HbA1c to their specific recognition elements were 5.18 Hz and 9.99 Hz, respectively. The within-run coefficients of variation (CV) were 1.84%, 2.18%, 1.72%, and 2.01%, whereas the run-to-run CVs were 2.11%, 2.41%, 2.08%, and 2.21%, when assaying two levels of haemoglobin and HbA1c, respectively. The CVs for the haemoglobin and HbA1c levels measured on ten independently fabricated paper-based sheets were 1.96% and 2.10%, respectively. These results demonstrated that our proposed system achieved excellent precision for the simultaneous detection of total haemoglobin and HbA1c, with an acceptable reproducibility of fabrication. The long-term stability of the Hp-modified eggshell membrane (ESM) was 98.84% over a shelf-life of 4 weeks, enabling the possibility of storage or long-distance transport to remote regions, particularly in resource-limited settings; however, for the APBA-modified ESM, the stability was 92.35% over a one-week period. Compared with the commercial automated method, the results demonstrated excellent agreement between the techniques (p-value < 0.05), thus permitting the potential application of 3D-PEID for the monitoring of the glycaemic status in diabetic patients. Copyright © 2016 Elsevier B.V. All rights reserved.

Decline in snail abundance due to soil acidification causes eggshell defects in forest passerines.

PubMed

Graveland, J; van der Wal, R

1996-02-01

On poor soils in the Netherlands an increasing number of great tits, Parus major, and of other forest passerines produce eggs with defective shells and have low reproductive success as a result of calcium deficiency. A similar increase in eggshell defects has been observed in Germany and Sweden. Snail shells are the main calcium source for tits in forests where defective eggshells do not occur, but are very little taken in forests where tits often have eggshell defects. We investigated whether a decrease in snail abundance on poor soils could be responsible for the decline in eggshell quality, and if so, what caused this decrease. Snail density in forests where tits have eggshell defects was much lower than in forests where tits do not have such defects. Snail density correlated with the calcium content and to a lesser extent with pH of the litter layer. Liming of a calciumpoor forest soil with few snails resulted in snail densities comparable to those on calcium-rich soils after 4 years. Snail density has declined on calcium-poor soils over the last two decades, but not on calcium-rich soils. Acid deposition has caused a decline of soil calcium on poor soils. We conclude, therefore, that anthropogenic acidification has caused a decline in snail populations, resulting in an increase in eggshell defects in birds in forests on poor soils.

Spin-echo based diagonal peak suppression in solid-state MAS NMR homonuclear chemical shift correlation spectra

NASA Astrophysics Data System (ADS)

Wang, Kaiyu; Zhang, Zhiyong; Ding, Xiaoyan; Tian, Fang; Huang, Yuqing; Chen, Zhong; Fu, Riqiang

2018-02-01

The feasibility of using the spin-echo based diagonal peak suppression method in solid-state MAS NMR homonuclear chemical shift correlation experiments is demonstrated. A complete phase cycling is designed in such a way that in the indirect dimension only the spin diffused signals are evolved, while all signals not involved in polarization transfer are refocused for cancellation. A data processing procedure is further introduced to reconstruct this acquired spectrum into a conventional two-dimensional homonuclear chemical shift correlation spectrum. A uniformly 13C, 15N labeled Fmoc-valine sample and the transmembrane domain of a human protein, LR11 (sorLA), in native Escherichia coli membranes have been used to illustrate the capability of the proposed method in comparison with standard 13C-13C chemical shift correlation experiments.

Multi-tissue analyses reveal limited inter-annual and seasonal variation in mercury exposure in an Antarctic penguin community.

PubMed

Brasso, Rebecka L; Polito, Michael J; Emslie, Steven D

2014-10-01

Inter-annual variation in tissue mercury concentrations in birds can result from annual changes in the bioavailability of mercury or shifts in dietary composition and/or trophic level. We investigated potential annual variability in mercury dynamics in the Antarctic marine food web using Pygoscelis penguins as biomonitors. Eggshell membrane, chick down, and adult feathers were collected from three species of sympatrically breeding Pygoscelis penguins during the austral summers of 2006/2007-2010/2011. To evaluate the hypothesis that mercury concentrations in penguins exhibit significant inter-annual variation and to determine the potential source of such variation (dietary or environmental), we compared tissue mercury concentrations with trophic levels as indicated by δ(15)N values from all species and tissues. Overall, no inter-annual variation in mercury was observed in adult feathers suggesting that mercury exposure, on an annual scale, was consistent for Pygoscelis penguins. However, when examining tissues that reflected more discrete time periods (chick down and eggshell membrane) relative to adult feathers, we found some evidence of inter-annual variation in mercury exposure during penguins' pre-breeding and chick rearing periods. Evidence of inter-annual variation in penguin trophic level was also limited suggesting that foraging ecology and environmental factors related to the bioavailability of mercury may provide more explanatory power for mercury exposure compared to trophic level alone. Even so, the variable strength of relationships observed between trophic level and tissue mercury concentrations across and within Pygoscelis penguin species suggest that caution is required when selecting appropriate species and tissue combinations for environmental biomonitoring studies in Antarctica.

Plasma membranes modified by plasma treatment or deposition as solid electrolytes for potential application in solid alkaline fuel cells.

PubMed

Reinholdt, Marc; Ilie, Alina; Roualdès, Stéphanie; Frugier, Jérémy; Schieda, Mauricio; Coutanceau, Christophe; Martemianov, Serguei; Flaud, Valérie; Beche, Eric; Durand, Jean

2012-07-30

In the highly competitive market of fuel cells, solid alkaline fuel cells using liquid fuel (such as cheap, non-toxic and non-valorized glycerol) and not requiring noble metal as catalyst seem quite promising. One of the main hurdles for emergence of such a technology is the development of a hydroxide-conducting membrane characterized by both high conductivity and low fuel permeability. Plasma treatments can enable to positively tune the main fuel cell membrane requirements. In this work, commercial ADP-Morgane® fluorinated polymer membranes and a new brand of cross-linked poly(aryl-ether) polymer membranes, named AMELI-32®, both containing quaternary ammonium functionalities, have been modified by argon plasma treatment or triallylamine-based plasma deposit. Under the concomitant etching/cross-linking/oxidation effects inherent to the plasma modification, transport properties (ionic exchange capacity, water uptake, ionic conductivity and fuel retention) of membranes have been improved. Consequently, using plasma modified ADP-Morgane® membrane as electrolyte in a solid alkaline fuel cell operating with glycerol as fuel has allowed increasing the maximum power density by a factor 3 when compared to the untreated membrane.

Plasma Membranes Modified by Plasma Treatment or Deposition as Solid Electrolytes for Potential Application in Solid Alkaline Fuel Cells

PubMed Central

Reinholdt, Marc; Ilie, Alina; Roualdès, Stéphanie; Frugier, Jérémy; Schieda, Mauricio; Coutanceau, Christophe; Martemianov, Serguei; Flaud, Valérie; Beche, Eric; Durand, Jean

2012-01-01

In the highly competitive market of fuel cells, solid alkaline fuel cells using liquid fuel (such as cheap, non-toxic and non-valorized glycerol) and not requiring noble metal as catalyst seem quite promising. One of the main hurdles for emergence of such a technology is the development of a hydroxide-conducting membrane characterized by both high conductivity and low fuel permeability. Plasma treatments can enable to positively tune the main fuel cell membrane requirements. In this work, commercial ADP-Morgane® fluorinated polymer membranes and a new brand of cross-linked poly(aryl-ether) polymer membranes, named AMELI-32®, both containing quaternary ammonium functionalities, have been modified by argon plasma treatment or triallylamine-based plasma deposit. Under the concomitant etching/cross-linking/oxidation effects inherent to the plasma modification, transport properties (ionic exchange capacity, water uptake, ionic conductivity and fuel retention) of membranes have been improved. Consequently, using plasma modified ADP-Morgane® membrane as electrolyte in a solid alkaline fuel cell operating with glycerol as fuel has allowed increasing the maximum power density by a factor 3 when compared to the untreated membrane. PMID:24958295

Linkage of microbial kinetics and bacterial community structure of MBR and hybrid MBBR-MBR systems to treat salinity-amended urban wastewater.

PubMed

Rodriguez-Sanchez, Alejandro; Leyva-Diaz, Juan Carlos; Gonzalez-Martinez, Alejandro; Poyatos, Jose Manuel

2017-11-01

Three pilot-scale bioreactors were started up and operated under salinity-amended urban wastewater feeding. The bioreactors were configured as membrane bioreactor and two different hybrid, moving bed biofilm reactor-membrane bioreactor and operated with a hydraulic retention time of 9.5 h, a solid residence time of 11.75 days and a total solids concentration of 2500 mg L -1 . The three systems showed excellent performance in suspended solids, BOD 5 , and COD removal (values of 96-100%, 97-99%, and 88-90%, respectively), but poor nitrogen removal (values of 20-30%). The bacterial community structure during the start-up phase and the stabilization phase were different, as showed by β-diversity analyses. The differences between aerobic and anoxic biomass-and between suspended and attached biomass-were higher at the start-up phase than at the stabilization phase. The start-up phase showed high abundances of Chiayiivirga (mean values around 3-12% relative abundance) and Luteimonas (5-8%), but in the stabilization phase, the domination belonged to Thermomonas (3-14%), Nitrobacter (3-7%), Ottowia (3-11.5%), and Comamonas (2-6%), among others. Multivariate redundancy analyses showed that Thermomonas and Nitrosomonas were positively correlated with fast autotrophic kinetics, while Caulobacter and Ottowia were positively correlated with fast heterotrophic kinetics. Nitrobacter, Rhodanobacter, and Comamonas were positively correlated with fast autotrophic and heterotrophic kinetics. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1483-1495, 2017. © 2017 American Institute of Chemical Engineers.

The role of python eggshell permeability dynamics in a respiration-hydration trade-off.

PubMed

Stahlschmidt, Zachary R; Heulin, Benoit; DeNardo, Dale F

2010-01-01

Parental care is taxonomically widespread because it improves developmental conditions and thus fitness of offspring. Although relatively simplistic compared with parental behaviors of other taxa, python egg-brooding behavior exemplifies parental care because it mediates a trade-off between embryonic respiration and hydration. However, because egg brooding increases gas-exchange resistance between embryonic and nest environments and because female pythons do not adjust their brooding behavior in response to the increasing metabolic requirements of developing offspring, python egg brooding imposes hypoxic costs on embryos during the late stages of incubation. We conducted a series of experiments to determine whether eggshells coadapted with brooding behavior to minimize the negative effects of developmental hypoxia. We tested the hypotheses that python eggshells (1) increase permeability over time to accommodate increasing embryonic respiration and (2) exhibit permeability plasticity in response to chronic hypoxia. Over incubation, we serially measured the atomic and structural components of Children's python (Antaresia childreni) eggshells as well as in vivo and in vitro gas exchange across eggshells. In support of our first hypothesis, A. childreni eggshells exhibited a reduced fibrous layer, became more permeable, and facilitated greater gas exchange as incubation progressed. Our second hypothesis was not supported, as incubation O(2) concentration did not affect the shells' permeabilities to O(2) and H(2)O vapor. Our results suggest that python eggshell permeability changes during incubation but that the alterations over time are fixed and independent of environmental conditions. These findings are of broad evolutionary interest because they demonstrate that, even in relatively simple parental-care models, successful parent-offspring relationships depend on adjustments made by both the parent (i.e., egg-brooding behavioral shifts) and the offspring (i.e., changes in eggshell permeability).

Criteria for the selection of a solid phase to be used in immunoassays.

PubMed

Delagneau, J F; Masseyeff, R

1990-01-01

Heterogeneous immunoassays are very sensitive and only limited in terms of performance by non specific binding. They require separation of free from bound fractions and concomitant use of a solid phase coated with an immunoreactive component (i.e. immunosorbent). The improvement of these key immunosorbents is crucial and involves a great deal of expertise and capabilities. Specifications differ according to procedure (e.g. capture or competitive assay). Each routinely used solid phase, such as polystyrene wells, porous membrane or dispersible microbeads, presents specific performance characteristics, advantages, and drawbacks. Among the tasks to be implemented are optimization of the spatial orientation of immunological reagents, selection of the surface neutral hydrophilic support, acceleration of reactions by increasing the reactive surface area of the supports, streamlining and simplification of procedural steps. These various aspects are abundantly described and emphasized here.

An innovative method for analysis of Pb (II) in rice, milk and water samples based on TiO2 reinforced caprylic acid hollow fiber solid/liquid phase microextraction.

PubMed

Bahar, Shahriyar; Es'haghi, Zarrin; Nezhadali, Azizollah; Banaei, Alireza; Bohlooli, Shahab

2017-04-15

In the present study, nano-sized titanium oxides were applied for preconcentration and determination of Pb(II) in aqueous samples using hollow fiber based solid-liquid phase microextraction (HF-SLPME) combined with flame atomic absorption spectrometry (FAAS). In this work, the nanoparticles dispersed in caprylic acid as an extraction solvent was placed into a polypropylene porous hollow fiber segment supported by capillary forces and sonification. This membrane was in direct contact with solutions containing Pb (II). The effect of experimental conditions on the extraction, such as pH, stirring rate, sample volume, and extraction time were optimized. Under the optimal conditions, the performance of the proposed method was investigated for the determination of Pb (II) in food and water samples. The method was linear in the range of 0.6-3000μgmL -1 . The relative standard deviations and relative recovery of Pb (II) was 4.9% and 99.3%, respectively (n=5). Copyright © 2016 Elsevier Ltd. All rights reserved.

Automated sample preparation using membrane microtiter extraction for bioanalytical mass spectrometry.

PubMed

Janiszewski, J; Schneider, P; Hoffmaster, K; Swyden, M; Wells, D; Fouda, H

1997-01-01

The development and application of membrane solid phase extraction (SPE) in 96-well microtiter plate format is described for the automated analysis of drugs in biological fluids. The small bed volume of the membrane allows elution of the analyte in a very small solvent volume, permitting direct HPLC injection and negating the need for the time consuming solvent evaporation step. A programmable liquid handling station (Quadra 96) was modified to automate all SPE steps. To avoid drying of the SPE bed and to enhance the analytical precision a novel protocol for performing the condition, load and wash steps in rapid succession was utilized. A block of 96 samples can now be extracted in 10 min., about 30 times faster than manual solvent extraction or single cartridge SPE methods. This processing speed complements the high-throughput speed of contemporary high performance liquid chromatography mass spectrometry (HPLC/MS) analysis. The quantitative analysis of a test analyte (Ziprasidone) in plasma demonstrates the utility and throughput of membrane SPE in combination with HPLC/MS. The results obtained with the current automated procedure compare favorably with those obtained using solvent and traditional solid phase extraction methods. The method has been used for the analysis of numerous drug prototypes in biological fluids to support drug discovery efforts.

Evaluating PCB Bioavailability Using Passive Samplers and Mussles at a Contaminated Sediment Site

EPA Science Inventory

Passive samplers, including semi-permeable membrane devices (SPMDs), solid phase microextraction (SPME) and polyethylene devices (PEDs), provide innovative tools for measuring hydrophobic organic contaminants (HOCs) originating from contaminated waters and sediments. Because the...

Composite electrolytes of polyethylene oxides/garnets interfacially wetted by ionic liquid for room-temperature solid-state lithium battery

NASA Astrophysics Data System (ADS)

Huo, Hanyu; Zhao, Ning; Sun, Jiyang; Du, Fuming; Li, Yiqiu; Guo, Xiangxin

2017-12-01

Paramount attention has been paid on solid polymer electrolytes due to their potential in enhancement of energy density as well as improvement of safety. Herein, the composite electrolytes consisting of Li-salt-free polyethylene oxides and 200 nm-sized Li6.4La3Zr1.4Ta0.6O12 particles interfacially wetted by [BMIM]TF2N of 1.8 μL cm-2 have been prepared. Such wetted ionic liquid remains the solid state of membrane electrolytes and decreases the interface impedance between the electrodes and the electrolytes. There is no release of the liquid phase from the PEO matrix when the pressure of 5.0 × 104 Pa being applied for 24 h. The interfacially wetted membrane electrolytes show the conductivity of 2.2 × 10-4 S cm-1 at 20 °C, which is one order of magnitude greater than that of the membranes without the wetted ionic liquids. The conduction mechanism is related to a large number of lithium ions releasing from Li6.4La3Zr1.4Ta0.6O12 particles and the improved conductive paths along the ion-liquid-wetted interfaces between the polymer matrix and ceramic grains. When the membranes being used in the solid-state LiFePO4/Li and LiFe0.15Mn0.85PO4/Li cells at 25 °C, the excellent rate capability and superior cycle stability has been shown. The results provide a new prospect for solid polymer electrolytes used for room-temperature solid-state lithium batteries.

On the mechanism of penetration of ovicidal fungi through egg-shells of parasitic nematodes. Decomposition of chitinous and ascaroside layers.

PubMed

Kunert, J

1992-01-01

The decomposition of egg-shells of Ascaris lumbricoides L. was studied microscopically using topochemical methods in a set of 32 strains of soil ovicidal fungi. It was found that even fungi displaying minimal chitinolytic activity in tests on purified chitin in vitro are able to dissolve chitin of egg-shells during the attack on live eggs. Fungi without any chitinolytic activity penetrate probably only the mechanically damaged eggs. None of the studied fungi was capable of degrading enzymatically the glycolipid (ascaroside) layer of the egg-shell which remained intact after digestion of all other components of the egg.

U-Th Burial Dates on Ostrich Eggshell

NASA Astrophysics Data System (ADS)

Sharp, W. D.; Fylstra, N. D.; Tryon, C. A.; Faith, J. T.; Peppe, D. J.

2015-12-01

Obtaining precise and accurate dates at archaeological sites beyond the range of radiocarbon dating is challenging but essential for understanding human origins. Eggshells of ratites (large flightless birds including ostrich, emu and others) are common in many archaeological sequences in Africa, Australia and elsewhere. Ancient eggshells are geochemically suitable for the U-Th technique (1), which has about ten times the range of radiocarbon dating (>500 rather than 50 ka), making eggshells attractive dating targets. Moreover, C and N isotopic studies of eggshell provide insights into paleovegetation and paleoprecipitation central to assessing past human-environment interactions (2,3). But until now, U-Th dates on ratite eggshell have not accounted for the secondary origin of essentially all of their U. We report a novel approach to U-Th dating of eggshell that explicitly accounts for secondary U uptake that begins with burial. Using ostrich eggshell (OES) from Pleistocene-Holocene east African sites, we have measured U and 232Th concentration profiles across OES by laser ablation ICP-MS. U commonly peaks at 10s to 100s of ppb and varies 10-fold or more across the ~2 mm thickness of OES, with gradients modulated by the layered structure of the eggshell. Common Th is high near the shell surfaces, but low in the middle "pallisade" layer of OES, making it optimal for U-Th dating. We determine U-Th ages along the U concentration gradient by solution ICP-MS analyses of two or more fractions of the pallisade layer. We then estimate OES burial dates using a simple model for diffusive uptake of uranium. Comparing such "U-Th burial dates" with radiocarbon dates for OES calcite from the same shells, we find good agreement in 7 out of 9 cases, consistent with rapid burial and confirming the accuracy of the approach. The remaining 2 eggshells have anomalous patterns of apparent ages that reveal they are unsuitable for U-Th dating, thereby providing reliability criteria innate to the U-Th data. The oldest OES we have analyzed yields a U-Th burial date of ~140 ka, indicating that U-Th burial dating of OES may be applicable throughout the Late Pleistocene. 1. Magee, J.W. et al. (2009) Quatern. Geochron. 4, 84-89. 2. Johnson, B.J. et al. (1998) Geochim. Cosmochim. Acta 62, 2451-2461. 3. Miller, G.H. et al. (2005) Science 309, 287-290.

Preparation of Interconnected Biomimetic Poly(vinylidene fluoride-co-chlorotrifluoroethylene) Hydrophobic Membrane by Tuning the Two-Stage Phase Inversion Process.

PubMed

Zheng, Libing; Wang, Jun; Wu, Zhenjun; Li, Jie; Zhang, Yong; Yang, Min; Wei, Yuansong

2016-11-30

A facile strategy was applied for poly(vinylidene fluoride-co-chlorotrifluoroethylene) (PVDF-CTFE) hydrophobic membrane preparation by tuning the two-stage phase inversion process. The exposure stage was found to benefit the solid-liquid demixing process (gelation/crystallization) induced by the solvent evaporation and the subsequent phase inversion induced by immersion benefit the liquid-liquid demixing. It was confirmed that the electrospun nanostructure-like biomimetic surface and interconnected pore structure can be expected by controlling the exposure duration, and 300 s was considered as the inflection point of exposure duration for PVDF-CTFE membrane through which a tremendous variation would show. The micro/nanohierarchical structure in the membrane surface owing to the crystallization of PVDF-CTFE copolymer was responsible for the improvement of membrane roughness and hydrophobicity. Meanwhile, the interconnected pore structure in both the surface and the cross-section, which were formed because of the crystallization process, offers more mass transfer passages and enhances the permeate flux. The membrane then showed excellent MD performance with high permeate flux, high salt rejection, and relatively high stability during a 48 h continuous DCMD operation, according to the morphology, pore structure, and properties, which can be a substitute for hydrophobic membrane application.

Laying date, incubation and egg breakage as determinants of bacterial load on bird eggshells: experimental evidence.

PubMed

Soler, Juan José; Ruiz-Rodríguez, Magdalena; Martín-Vivaldi, Manuel; Peralta-Sánchez, Juan Manuel; Ruiz-Castellano, Cristina; Tomás, Gustavo

2015-09-01

Exploring factors guiding interactions of bacterial communities with animals has become of primary importance for ecologists and evolutionary biologists during the last years because of their likely central role in the evolution of animal life history traits. We explored the association between laying date and eggshell bacterial load (mesophilic bacteria, Enterobacteriaceae, Staphylococci, and Enterococci) in natural and artificial magpie (Pica pica) nests containing fresh commercial quail (Coturnix coturnix) eggs. We manipulated hygiene conditions by spilling egg contents on magpie and artificial nests and explored experimental effects during the breeding season. Egg breakage is a common outcome of brood parasitism by great spotted cuckoos (Clamator glandarius) on the nests of magpie, one of its main hosts. We found that the treatment increased eggshell bacterial load in artificial nests, but not in magpie nests with incubating females, which suggests that parental activity prevents the proliferation of bacteria on the eggshells in relation to egg breakage. Moreover, laying date was positively related to eggshell bacterial load in active magpie nests, but negatively in artificial nests. The results suggest that variation in parental characteristics of magpies rather than climatic variation during the breeding season explained the detected positive association. Because the eggshell bacterial load is a proxy of hatching success, the detected positive association between eggshell bacterial loads and laying date in natural, but not in artificial nests, suggests that the generalized negative association between laying date and avian breeding success can be, at least partially, explained by differential bacterial effects.

Mechanics of Fluctuating Elastic Plates and Fiber Networks

NASA Astrophysics Data System (ADS)

Liang, Xiaojun

Lipid membranes and fiber networks in biological systems perform important mechanical functions at the cellular and tissue levels. In this thesis I delve into two detailed problems--thermal fluctuation of membranes and non-linear compression response of fiber networks. Typically, membrane fluctuations are analysed by decomposing into normal modes or by molecular simulations. In the first part of my thesis, I propose a new semi-analytic method to calculate the partition function of a membrane. The membrane is viewed as a fluctuating von Karman plate and discretized into triangular elements. Its energy is expressed as a function of nodal displacements, and then the partition function and co-variance matrix are computed using Gaussian integrals. I recover well-known results for the dependence of the projected area of a lipid bilayer membrane on the applied tension, and recent simulation results on the ependence of membrane free energy on geometry, spontaneous curvature and tension. As new applications I use this technique to study a membrane with heterogeneity and different boundary conditions. I also use this technique to study solid membranes by taking account of the non-linear coupling of in-plane strains with out-of-plane deflections using a penalty energy, and apply it to graphene, an ultra-thin two-dimensional solid. The scaling of graphene fluctuations with membrane size is recovered. I am able to capture the dependence of the thermal expansion coefficient of graphene on temperature. Next, I study curvature mediated interactions between inclusions in membranes. I assume the inclusions to be rigid, and show that the elastic and entropic forces between them can compete to yield a local maximum in the free energy if the membrane bending modulus is small. If the spacing between the inclusions is less than this local maximum then the attractive entropic forces dominate and the separation between the inclusions will be determined by short range interactions; if the spacing is more than the local maximum then the elastic repulsive forces dominate and the inclusions will move further apart. This technique can be extended to account for entropic effects in other methods which rely on quadratic energies to study the interactions of inclusions in membranes. In the second part of this thesis I study the compression response of two fiber network materials--blood clots and carbon nanotube forests. The stress-strain curve of both materials reveals four characteristic regions, for compression-decompression: 1) linear elastic region; 2) upper plateau or softening region; 3) non-linear elastic region or re-stretching of the network; 4) lower plateau in which dissociation of some newly made connections occurs. This response is described by a phase transition based continuum model. The model is inspired by the observation of one or more moving interfaces across which densified and rarefied phases of fibers co-exist. I use a quasi-static version of the Abeyaratne-Knowles theory of phase transitions for continua with a stick-slip type kinetic law and a nucleation criterion based on the critical stress for buckling to describe the formation and motion of these interfaces in uniaxial compression experiments. Our models could aid the design of biomaterials and carbon nanotube forests to have desired mechanical properties and guide further understanding of their behavior under large deformations.

Bactericidal Effect of Calcium Oxide (Scallop-Shell Powder) Against Pseudomonas aeruginosa Biofilm on Quail Egg Shell, Stainless Steel, Plastic, and Rubber.

PubMed

Jung, Soo-Jin; Park, Shin Young; Kim, Seh Eun; Kang, Ike; Park, Jiyong; Lee, Jungwon; Kim, Chang-Min; Chung, Myung-Sub; Ha, Sang-Do

2017-07-01

The aim of this study was to evaluate the bactericidal effect of calcium oxide (CaO) against Pseudomonas aeruginosa biofilms on quail eggshells and major egg contacting surfaces (stainless steel, plastic, and rubber). The samples were subjected to CaO treatments (0%, 0.01%, 0.05%, 0.10%, 0.15%, 0.20%, 0.25%, and 0.30%) for 1 min. All the CaO treatments significantly reduced P. aeruginosa biofilms on all tested surfaces as compared to controls. In comparison of biofilm stability, the strongest and most resistant biofilm was formed on eggshell against the CaO treatment, followed by rubber, stainless steel, and plastic. In evaluation of bactericidal effect, the largest reduction (3.16 log CFU) was observed in plastic even at the lowest concentration of CaO (0.01%), whereas the least reduction was found in eggshells, regardless of CaO concentration. In addition, stainless steel showed a significant reduction in biofilm formation at all concentrations except 0.10% to 0.15% CaO. At 0.30% CaO, the reduction of P. aeruginosa in biofilms on stainless steel, plastic, rubber, and eggshell were 5.48, 6.37, 4.87, and 3.14 log CFU/cm 2 (CFU/egg), respectively. Biofilm reduction after CaO treatment was also observed by field emission scanning electron microscopy (FE-SEM). Based on the FE-SEM images, we observed that P. aeruginosa biofilms formed compact aggregations on eggshell surfaces with CaO treatments up to 0.30%. More specifically, a 0.20% CaO treatment resulted in the reductions of 3 to 6 log CFU in all materials. © 2017 Institute of Food Technologists®.

Flexible robust binder-free carbon nanotube membranes for solid state and microcapacitor application

NASA Astrophysics Data System (ADS)

Adu, Kofi; Ma, Danhao; Wang, Yuxiang; Spencer, Michael; Rajagopalan, Ramakrishnan; Wang, C.-Yu; Randall, Clive

2018-01-01

We present a liquid phase post synthesis self-assemble protocol that transforms trillions of carbon nanotubes (CNTs) in powder form into densely packed flexible, robust and binder-free macroscopic membranes with a hierarchical pore structure. We employ charge transfer engineering to spontaneously disperse the CNTs in a liquid medium. The processing protocol has limited or no impact on the intrinsic properties of the CNTs. As the thickness of the CNT membrane is increased, we observed a gradual transition from high flexibility to buckling and brittleness in the flexural properties of the membranes. The binder-free CNT membranes have bulk mass density greater than that of water (1.0 g cm-3). We correlate the mass of the CNTs in the membrane to the thickness of the membrane and obtained a bulk mass density of ˜1.11 g cm-3 ± 0.03 g cm-3. We demonstrate the use of the CNT membranes as electrode in a pristine and oxidized single/stacked solid-state capacitor as well as pristine interdigitated microcapacitor that show time constant of ˜32 ms with no degradation in performance even after 10 000 cycles. The capacitors show very good temperature dependence over a wide range of temperatures with good cycling performance up to 90 °C. The specific capacitance of the pseudocapacitive CNT electrode at room temperature was 72 F g-1 and increased to 100 F g-1 at 70 °C. The leakage current of bipolar stacked solid state capacitor was ˜100 nA cm-2 at 2.5 V when held for 72 h.

Synthesis of Stable Microcapsules from Trematode Eggshell Components

DTIC Science & Technology

1990-06-30

NO Arlington, VA 22217-5000 61153N RR4106 11 TITLE (Include Security Classification) (u) Synthesis of Stable Microcapsules from Trematode Eggshell...Continue on reverse if necessary and identify by block number) The trematode Fasciola hepatica produces a unique protein eggshell or microcapsule the...proteins to produce a hard quinone tanned microcapsule with unusual properties. The focus of this project is to i) characterize the protein components

Eggshell permeability: a standard technique for determining interspecific rates of water vapor conductance.

PubMed

Portugal, Steven J; Maurer, Golo; Cassey, Phillip

2010-01-01

Typically, eggshell water vapor conductance is measured on whole eggs, freshly collected at the commencement of a study. At times, however, it may not be possible to obtain whole fresh eggs but rather egg fragments or previously blown eggs. Here we evaluate and describe in detail a technique for modern laboratory analysis of eggshell conductance that uses fragments from fresh and museum eggs to determine eggshell water vapor conductance. We used fresh unincubated eggs of domesticated chickens (Gallus gallus domesticus), ducks (Anas platyrhynchos domesticus), and guinea fowl (Numida meleagris) to investigate the reliability, validity, and repeatability of the technique. To assess the suitability of museum samples, museum and freshly collected black-headed gull eggs (Larus ridibundus) were used. Fragments were cut out of the eggshell from the blunt end (B), equator (E), and pointy end (P). Eggshell fragments were glued to the top of a 0.25-mL micro test tube (Eppendorf) filled with 200 μL of distilled water and placed in a desiccator at 25°C. Eppendorfs were weighed three times at 24-h intervals, and mass loss was assumed to be a result of water evaporation. We report the following results: (1) mass loss between weighing sessions was highly repeatable and consistent in all species; (2) the majority of intraspecific variability in eggshell water vapor conductance between different eggs of the same species was explained through the differences in water vapor conductance between the three eggshell parts of the same egg (B, E, and P); (3) the technique was sensitive enough to detect significant differences between the three domestic species; (4) there was no overall significant difference between water vapor conductance of museum and fresh black-headed gull eggs; (5) there was no significant difference in water vapor conductance for egg fragments taken from the same egg both between different trials and within the same trial. We conclude, therefore, that this technique is an effective way of measuring interspecific water vapor conductance from eggshell fragments and that museum eggs are a suitable resource for such work.

Efficient Broadband Simulation of Fluid-Structure Coupling for Membrane-Type Acoustic Transducer Arrays Using the Multilevel Fast Multipole Algorithm.

PubMed

Shieh, Bernard; Sabra, Karim G; Degertekin, F Levent

2016-11-01

A boundary element model provides great flexibility for the simulation of membrane-type micromachined ultrasonic transducers (MUTs) in terms of membrane shape, actuating mechanism, and array layout. Acoustic crosstalk is accounted for through a mutual impedance matrix that captures the primary crosstalk mechanism of dispersive-guided modes generated at the fluid-solid interface. However, finding the solution to the fully populated boundary element matrix equation using standard techniques requires computation time and memory usage that scales by the cube and by the square of the number of nodes, respectively, limiting simulation to a small number of membranes. We implement a solver with improved speed and efficiency through the application of a multilevel fast multipole algorithm (FMA). By approximating the fields of collections of nodes using multipole expansions of the free-space Green's function, an FMA solver can enable the simulation of hundreds of thousands of nodes while incurring an approximation error that is controllable. Convergence is drastically improved using a problem-specific block-diagonal preconditioner. We demonstrate the solver's capabilities by simulating a 32-element 7-MHz 1-D capacitive MUT (CMUT) phased array with 2880 membranes. The array is simulated using 233280 nodes for a very wide frequency band up to 50 MHz. For a simulation with 15210 nodes, the FMA solver performed ten times faster and used 32 times less memory than a standard solver based on LU decomposition. We investigate the effects of mesh density and phasing on the predicted array response and find that it is necessary to use about seven nodes over the width of the membrane to observe convergence of the solution-even below the first membrane resonance frequency-due to the influence of higher order membrane modes.

Isolation, Separation, and Preconcentration of Biologically Active Compounds from Plant Matrices by Extraction Techniques.

PubMed

Raks, Victoria; Al-Suod, Hossam; Buszewski, Bogusław

2018-01-01

Development of efficient methods for isolation and separation of biologically active compounds remains an important challenge for researchers. Designing systems such as organomineral composite materials that allow extraction of a wide range of biologically active compounds, acting as broad-utility solid-phase extraction agents, remains an important and necessary task. Selective sorbents can be easily used for highly selective and reliable extraction of specific components present in complex matrices. Herein, state-of-the-art approaches for selective isolation, preconcentration, and separation of biologically active compounds from a range of matrices are discussed. Primary focus is given to novel extraction methods for some biologically active compounds including cyclic polyols, flavonoids, and oligosaccharides from plants. In addition, application of silica-, carbon-, and polymer-based solid-phase extraction adsorbents and membrane extraction for selective separation of these compounds is discussed. Potential separation process interactions are recommended; their understanding is of utmost importance for the creation of optimal conditions to extract biologically active compounds including those with estrogenic properties.

Integrated photografted molecularly imprinted polymers with a cellulose acetate membrane for the extraction of melamine from dry milk before HPLC analysis.

PubMed

Akbari-Adergani, Behrouz; Sadeghian, Gholam-Hossein; Alimohammadi, Alireza; Esfandiari, Zahra

2017-03-01

In this study, a new separation technique based on membrane extraction is described for the determination of melamine in dry milk. The water-compatible cellulose acetate membrane, which is photografted by melamine imprinted nanospheres, was prepared by placing the membrane into the polymerization solution containing methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as cross-linker, acetonitrile as porogen, and melamine as the template molecule. The characterization of the polymeric membrane was performed by Fourier transmission infrared spectroscopy and scanning electron microscopy. This integrated composite membrane was used as a solid-phase extraction medium for the extraction of melamine from dry milk samples. Various parameters affecting the extraction efficiency of the membrane were evaluated. The results showed higher binding capacity for melamine imprinted membranes in comparison with the nonimprinted membranes. High-performance liquid chromatography analysis showed that the extraction of melamine from dry milk by the photografted cellulose acetate membrane had a linear calibration curve in the range of 0.02-11.80 μg/mL with an excellent precision of 2.73%. The limit of detection and quantification of melamine was 0.007 and 0.020 μg/mL, respectively. The recoveries of melamine were in the range of 88.7-94.8%. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ancient DNA Reveals Late Pleistocene Existence of Ostriches in Indian Sub-Continent.

PubMed

Jain, Sonal; Rai, Niraj; Kumar, Giriraj; Pruthi, Parul Aggarwal; Thangaraj, Kumarasamy; Bajpai, Sunil; Pruthi, Vikas

2017-01-01

Ancient DNA (aDNA) analysis of extinct ratite species is of considerable interest as it provides important insights into their origin, evolution, paleogeographical distribution and vicariant speciation in congruence with continental drift theory. In this study, DNA hotspots were detected in fossilized eggshell fragments of ratites (dated ≥25000 years B.P. by radiocarbon dating) using confocal laser scanning microscopy (CLSM). DNA was isolated from five eggshell fragments and a 43 base pair (bp) sequence of a 16S rRNA mitochondrial-conserved region was successfully amplified and sequenced from one of the samples. Phylogenetic analysis of the DNA sequence revealed a 92% identity of the fossil eggshells to Struthio camelus and their position basal to other palaeognaths, consistent with the vicariant speciation model. Our study provides the first molecular evidence for the presence of ostriches in India, complementing the continental drift theory of biogeographical movement of ostriches in India, and opening up a new window into the evolutionary history of ratites.

A deep-time CO2 barometer based on triple oxygen isotope compositions of dinosaurian eggshell carbonate

NASA Astrophysics Data System (ADS)

Hu, H.; Passey, B. H.; Montanari, S.; Levin, N.; Li, S.

2013-12-01

Photochemical reactions in the stratosphere lead to mass independent fractionation of oxygen isotopes: oxygen exchange among O2, O3, and CO2 produces 17O-enriched O3 and CO2, and 17O-depleted O2. This effect increases with increasing atmospheric CO2 concentration, and thus the 17O anomaly of O2, Δ17O (O2), is reflective of pCO2. Animals incorporate this signal into body water via respiration, and minerals such as bioapatite and eggshell calcite forming in equilibrium with body water can preserve the signal for millions of years. We contribute to the development of this new pCO2 barometer by developing analytical methods for high-precision triple oxygen isotope analysis of carbonates, by developing an ecophysiological model of body water triple oxygen isotopes, and by applying the method to eggshell from modern birds and late Cretaceous (Campanian and Maastrichtian) dinosaur eggshells. Our findings include the following: (1) If animal ecophysiology and climatic context are perfectly known, the sensitivity of Δ17O (body water) to atmospheric CO2 is on the order of 0.01 ‰ per 100 ppm CO2; our analytical precision is ~ 0.01 ‰, thus ultimately permitting sub -100 ppm - level pCO2 reconstructions. (2) However, the effect of ecophysiology and climate can lead to a range in Δ17O (body water) of about 0.15 ‰ for animals living under the same Δ17O (O2); this prediction, confirmed by analyses of eggshells and body water of modern birds, translates to an apparent pCO2 range of about 1500 ppm. (3) Animals that are highly dependent on unevaporated free surface water ('drinking water') and live in humid climates have Δ17O (body water) signals that mimic low pCO2, whereas animals that consume primarily evaporated water (e.g., leaf water) and living in arid environments have Δ17O (body water) signals that mimic high pCO2. (4) There is an upper limit to this 'evaporation / aridity' effect mimicking high pCO2, so Δ17O (fossil eggshell) can be modeled assuming such upper limits to produce conservative lower limits on estimates of past pCO2. (5) We find that late Cretaceous Δ17O (fossil eggshell) is generally lower than modern Δ17O (eggshell), implying generally higher pCO2 during the late Cretaceous. The lowest observed Δ17O (fossil eggshell) value implies CO2 levels of at least 1200 ppm, and probably closer to 2000 ppm, for at least a short interval of Campanian time. Overall, this triple oxygen isotope approach shows promise for placing constraints on past CO2 levels. While somewhat limited in precision, it has the benefits of little appreciable loss of sensitivity with increasing pCO2, no presently-known mechanism for generating 'false positive' estimates of high pCO2 (except for extremely low atmospheric O2 levels and low primary productivity), and a basis that is fundamentally different from existing methods, thus allowing for independent new constraints on past CO2 levels.

Cathode and electrolyte materials for solid oxide fuel cells and ion transport membranes

DOEpatents

Jacobson, Allan J; Wang, Shuangyan; Kim, Gun Tae

2014-01-28

Novel cathode, electrolyte and oxygen separation materials are disclosed that operate at intermediate temperatures for use in solid oxide fuel cells and ion transport membranes based on oxides with perovskite related structures and an ordered arrangement of A site cations. The materials have significantly faster oxygen kinetics than in corresponding disordered perovskites.

Application of the solid phase C1q and Raji cell radioimmune assays for the detection of circulating immune complexes in glomerulonephritis.

PubMed Central

Tung, K S; Woodroffe, A J; Ahlin, T D; Williams, R C; Wilson, C B

1978-01-01

The C1q solid phase and Raji cell radioimmune assays were used to determine the frequency of detectable circulating immune complexes in patients with glomerulonephritis. In this study, 46% of 56 patients with glomerulonephritis had evidence of circulating immune complexes. More important, circulating immune complexes were associated with some, but not other, types of glomerulonephritis. Thus, immune complexes were detected in lupus glomerulonephritis (9/9 patients), rapidly progressive glomerulonephritis (5/6 patients), and acute nephritis (5/6 patients), but not in IgA-IgG glomerulonephritis (0/7 patients), or membranous glomerulonephritis (0/8 patients). The Raji cell radioimmune assay and the C1q solid phase radioimmune assay showed concordance of 79% in the detection of circulating immune complexes. Serial determinations, in general, showed either persistence of a negative or positive result of conversion of positive to negative. PMID:659639

Dynamic Structure of Bombolitin II Bound to Lipid Bilayers as Revealed by Solid-state NMR and Molecular-Dynamics Simulation

PubMed Central

Toraya, Shuichi; Javkhlantugs, Namsrai; Mishima, Daisuke; Nishimura, Katsuyuki; Ueda, Kazuyoshi; Naito, Akira

2010-01-01

Bombolitin II (BLT2) is one of the hemolytic heptadecapeptides originally isolated from the venom of a bumblebee. Structure and orientation of BLT2 bound to 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) membranes were determined by solid-state 31P and 13C NMR spectroscopy. 31P NMR spectra showed that BLT2-DPPC membranes were disrupted into small particles below the gel-to-liquid crystalline phase transition temperature (Tc) and fused to form a magnetically oriented vesicle system where the membrane surface is parallel to the magnetic fields above the Tc. 13C NMR spectra of site-specifically 13C-labeled BLT2 at the carbonyl carbons were observed and the chemical shift anisotropies were analyzed to determine the dynamic structure of BLT2 bound to the magnetically oriented vesicle system. It was revealed that the membrane-bound BLT2 adopted an α-helical structure, rotating around the membrane normal with the tilt angle of the helical axis at 33°. Interatomic distances obtained from rotational-echo double-resonance experiments further showed that BLT2 adopted a straight α-helical structure. Molecular dynamics simulation performed in the BLT2-DPPC membrane system showed that the BLT2 formed a straight α-helix and that the C-terminus was inserted into the membrane. The α-helical axis is tilted 30° to the membrane normal, which is almost the same as the value obtained from solid-state NMR. These results suggest that the membrane disruption induced by BLT2 is attributed to insertion of BLT2 into the lipid bilayers. PMID:21081076

Array of planar membrane modules for producing hydrogen

DOEpatents

Vencill, Thomas R [Albuquerque, NM; Chellappa, Anand S [Albuquerque, NM; Rathod, Shailendra B [Hillsboro, OR

2012-05-08

A shared or common environment membrane reactor containing a plurality of planar membrane modules with top and bottom thin foil membranes supported by both an intermediary porous support plate and a central base which has both solid extended members and hollow regions or a hollow region whereby the two sides of the base are in fluid communication. The membrane reactor operates at elevate temperatures for generating hydrogen from hydrogen rich feed fuels.

Human predation contributed to the extinction of the Australian megafaunal bird Genyornis newtoni ∼47 ka

PubMed Central

Miller, Gifford; Magee, John; Smith, Mike; Spooner, Nigel; Baynes, Alexander; Lehman, Scott; Fogel, Marilyn; Johnston, Harvey; Williams, Doug; Clark, Peter; Florian, Christopher; Holst, Richard; DeVogel, Stephen

2016-01-01

Although the temporal overlap between human dispersal across Australia and the disappearance of its largest animals is well established, the lack of unambiguous evidence for human–megafauna interactions has led some to question a human role in megafaunal extinction. Here we show that diagnostic burn patterns on eggshell fragments of the megafaunal bird Genyornis newtoni, found at >200 sites across Australia, were created by humans discarding eggshell in and around transient fires, presumably made to cook the eggs. Dating by three methods restricts their occurrence to between 53.9 and 43.4 ka, and likely before 47 ka. Dromaius (emu) eggshell occur frequently in deposits from >100 ka to present; burnt Dromaius eggshell first appear in deposits the same age as those with burnt Genyornis eggshell, and then continually to modern time. Harvesting of their eggs by humans would have decreased Genyornis reproductive success, contributing to the bird's extinction by ∼47 ka. PMID:26823193

Effects of organochlorine residues on eggshell thickness, reproduction, and population status of brown pelicans (Pelecanus occidentalis) in South Carolina and Florida, 1969-76

USGS Publications Warehouse

Blus, L.J.; Lamont, T.G.; Neely, B.S.

1979-01-01

Shells of brown pelican (Pelecanus occidentalis) eggs collected in South Carolina from 1969 through 1975 and in Florida during 1969, 1970, and 1974 were significantly thinner (P greater than 0.05) than eggshells collected before 1947. Thickness of South Carolina eggshells increased in 1975, and mean thickness of eggshells collected in Florida during 1974 was greater than that of eggshells collected during 1969 and 1970, primarily in Gulf Coast colonies. Residues of 13 organochlorines were found in eggs and tissues of pelicans found dead during 1974 and 1975, although residues in brains of these specimens were not high enough to cause death. Residues of organochlorines, except PCBs, declined through 1975. PCBs increased in eggs from Atlantic Coast colonies. Reproductive success and population status of brown pelicans in South Carolina have improved markedly since authors began their studies in 1969. Good reproductive success was reported in 3 of 5 years from 1973 through 1977.

How the oxygen isotope ratio of rain water influences the isotope ratio of chicken eggshell carbonate

NASA Astrophysics Data System (ADS)

Price, Gregory; Grimes, Stephen

2015-04-01

The stable oxygen isotope ratio of chicken eggshell carbonate was analysed from chicken eggs laid under free range, and organic farming regimes from across the UK. The eggshell carbonate oxygen isotope data shows a clear depletion in delta18O distribution from the southwest to the northeast. Although consistently offset by around 1 permil, the same isotopic distribution as that seen in eggshell carbonate is observed in the delta18O ratio of rainfall and groundwater from across the UK. This distribution is related to the Rayleigh distillation of rainfall driven by westerly winds across the UK landmass. The clear relationship observed between eggshell delta18O values and that of rainwater presumably reflects the nature of free range chickens which must be drinking locally derived rainwater and supplementing their diet and water intake with locally derived food. These results suggest that the oxygen isotope value of chicken eggshells can be used as a forensic tool to identify the locality that free range and organic eggs were laid within the UK. Furthermore, if suitable material is preserved in the archaeological and geological record then such a relationship can potentially be used to establish the oxygen isotope value of rainwater from which ancient and / or ancestral birds lived.

Effects of Eggshell Calcium Supplementation on Bone Mass in Postmenopausal Vietnamese Women.

PubMed

Sakai, Seigo; Hien, Vu Thi Thu; Tuyen, Le Danh; Duc, Ha Anh; Masuda, Yasunobu; Yamamoto, Shigeru

2017-01-01

Bone mass decreases along with aging, especially for women after menopause because of lower estrogen secretion together with low calcium intake. This study was conducted to study the effect of eggshell calcium supplementation on bone mass in 54 postmenopausal Vietnamese women living in a farming area about 60 km from Hanoi, Vietnam. Sets of 3 subjects matched by age, bone mass, BMI and calcium intake were divided randomly into 3 groups with 18 subjects in each group. The eggshell calcium group was administered 300 mg/d calcium from eggshell, the calcium carbonate group 300 mg/d calcium from calcium carbonate and the placebo group received no calcium supplementation. Bone mass (Speed of Sound (SOS)) was measured at the beginning (the baseline), the middle (6th month) and the end of the study (12th month) by the single blind method. SOS of the eggshell group increased significantly at 12 mo (p<0.05) and was significantly higher than that of the placebo and calcium carbonate groups at 12 mo (p<0.05). The SOS of the calcium carbonate group tended to be higher than that of the placebo group but without a significant difference (p>0.05). In conclusion, eggshell calcium was more effective in increasing bone mass than calcium carbonate in postmenopausal Vietnamese women.

Atmospheric pressure plasma jet treatment of Salmonella Enteritidis inoculated eggshells.

PubMed

Moritz, Maike; Wiacek, Claudia; Koethe, Martin; Braun, Peggy G

2017-03-20

Contamination of eggshells with Salmonella Enteritidis remains a food safety concern. In many cases human salmonellosis within the EU can be traced back to raw or undercooked eggs and egg products. Atmospheric pressure plasma is a novel decontamination method that can reduce a wide range of pathogens. The aim of this work was to evaluate the possibility of using an effective short time cold plasma treatment to inactivate Salmonella Enteritidis on the eggshell. Therefore, artificially contaminated eggshells were treated with an atmospheric pressure plasma jet under different experimental settings with various exposure times (15-300s), distances from the plasma jet nozzle to the eggshell surface (5, 8 or 12mm), feed gas compositions (Ar, Ar with 0.2, 0.5 or 1.0% O 2 ), gas flow rates (5 and 7slm) and different inoculations of Salmonella Enteritidis (10 1 -10 6 CFU/cm 2 ). Atmospheric pressure plasma could reduce Salmonella Enteritidis on eggshells significantly. Reduction factors ranged between 0.22 and 2.27 log CFU (colony-forming units). Exposure time and, particularly at 10 4 CFU/cm 2 inoculation, feed gas had a major impact on Salmonella reduction. Precisely, longer exposure times led to higher reductions and Ar as feed gas was more effective than ArO 2 mixtures. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of layered double hydroxide/graphene hybrid as a sorbent in membrane-protected stir-bar supported micro-solid-phase extraction for determination of organochlorine pesticides in urine samples.

PubMed

Sajid, Muhammad; Basheer, Chanbasha; Daud, Muhammad; Alsharaa, Abdulnaser

2017-03-17

In this work, the potential of layered double hydroxide/graphene (LDH-G) hybrid as a sorbent for extraction and preconcentration of fifteen organochlorine pesticides (OCPs) in urine samples was evaluated. The LDH-G hybrid was synthesized by co-precipitation method and it was then characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The sorbent was then employed in membrane-protected stir-bar supported micro-solid-phase extraction (SB-μ-SPE) of OCPs in urine samples. This extraction approach is highly suitable for the samples representing matrix complexity such as urine because the sorbent is effectively protected inside the membrane. The extracted samples were analyzed by gas chromatography mass spectrometry. The factors that affect the performance of SB-μ-SPE were suitably optimized. This method demonstrated good linearity with coefficients of determination up to 0.9996. The limits of detection ranged between 0.22 and 1.38ngmL -1 . The RSD values for intra and inter-day precision were also in a satisfactory range (2.7-9.5%). Copyright © 2017 Elsevier B.V. All rights reserved.

Potential ecotoxicological significance of elevated concentrations of strontium in eggshells of passerine birds

USGS Publications Warehouse

Mora, Miguel A.; Taylor, Robert J.; Brattin, Bryan L.

2007-01-01

We investigated the occurrence and potential ecotoxicological significance of elevated concentrations of strontium (Sr) in eggshells of nine passerine birds from four regions in Arizona. Concentrations of Sr in eggshells ranged from 70 to 1360 µg g−1 dry weight (overall mean  =  684 ± 345 SD µg g−1 dw) for the four regions. 23% of the eggshells had Sr concentrations greater than 1000 µg g−1 dw. To our knowledge, these are among the highest levels of Sr that have been reported in bird eggshells in North America. Of the nine species, Brown-headed Cowbirds (Molothrus ater) had the greatest concentrations of Sr. There was a significant positive correlation between Sr and calcium (Ca), and between barium (Ba) and Ca. Ca, Sr, and Ba interact with each other and can exert similar chemical and pharmacological effects. Mean (n ≥ 3) eggshell∶egg ratios for Sr varied with species and ranged from 6.1∶1 to 40.2∶1; ratios for individual eggs reached 92.7∶1. Mean Sr/Ca values ranged from 1.3 × 10−3 to 3.0 × 10−3 and mean eggshell thickness ranged from 83 ± 6 to 120 ± 9 µm for all species. Eggshell thickness was not significantly correlated with Sr for any species but tended to increase with Sr concentrations. We postulate that high concentrations of Sr in the shell could affect later-stage embryos by possible interference with Ca metabolism and bone growth, resulting in reduced hatching success and potential minor beak deformities.

Optimization of Parameters for Manufacture Nanopowder Bioceramics at Machine Pulverisette 6 by Taguchi and ANOVA Method

NASA Astrophysics Data System (ADS)

Van Hoten, Hendri; Gunawarman; Mulyadi, Ismet Hari; Kurniawan Mainil, Afdhal; Putra, Bismantoloa dan

2018-02-01

This research is about manufacture nanopowder Bioceramics from local materials used Ball Milling for biomedical applications. Source materials for the manufacture of medicines are plants, animal tissues, microbial structures and engineering biomaterial. The form of raw material medicines is a powder before mixed. In the case of medicines, research is to find sources of biomedical materials that will be in the nanoscale powders can be used as raw material for medicine. One of the biomedical materials that can be used as raw material for medicine is of the type of bioceramics is chicken eggshells. This research will develop methods for manufacture nanopowder material from chicken eggshells with Ball Milling using the Taguchi method and ANOVA. Eggshell milled using a variation of Milling rate on 150, 200 and 250 rpm, the time variation of 1, 2 and 3 hours and variations the grinding balls to eggshell powder weight ratio (BPR) 1: 6, 1: 8, 1: 10. Before milled with Ball Milling crushed eggshells in advance and calcinate to a temperature of 900°C. After the milled material characterization of the fine powder of eggshell using SEM to see its size. The result of this research is optimum parameter of Taguchi Design analysis that is 250 rpm milling rate, 3 hours milling time and BPR is 1: 6 with the average eggshell powder size is 1.305 μm. Milling speed, milling time and ball to powder weight of ratio have contribution successively equal to 60.82%, 30.76% and 6.64% by error equal to 1.78%.

Nest Bacterial Environment Affects Microbiome of Hoopoe Eggshells, but Not That of the Uropygial Secretion

PubMed Central

Martínez-García, Ángela; Martín-Vivaldi, Manuel; Rodríguez-Ruano, Sonia M.; Peralta-Sánchez, Juan Manuel; Valdivia, Eva; Soler, Juan J.

2016-01-01

The study of associations between symbiotic bacterial communities of hosts and those of surrounding environments would help to understand how bacterial assemblages are acquired, and how they are transmitted from one to another location (i.e. symbiotic bacteria acquisition by hosts). Hoopoes (Upupa epops) smear their eggshells with uropygial secretion (oily secretion produced in their uropygial gland) that harbors antibiotic producing bacteria. Trying to elucidate a possible role of nest material and cloaca microbiota in determining the bacterial community of the uropygial gland and the eggshells of hoopoes, we characterized bacterial communities of nest material, cloaca, uropygial gland and eggshells by the ARISA fingerprinting. Further, by adding material with scarce bacteria and antimicrobial properties, we manipulated the bacterial community of nest material and thus tested experimentally its effects on the microbiomes of the uropygial secretion and of the eggshells. The experiment did not influence the microbiome of the uropygial secretion of females, but affected the community established on eggshells. This is the first experimental evidence indicating that nest material influences the bacterial community of the eggshells and, therefore, probability of embryo infection. Some of the bacterial strains detected in the secretion were also in the bacterial communities of the nest material and of cloaca, but their occurrence within nests was not associated, which suggests that bacterial environments of nest material and cloaca are not sources of symbiotic bacteria for the gland. These results do not support a role of nest environments of hoopoes as reservoirs of symbiotic bacteria. We discuss possible scenarios explaining bacterial acquisition by hoopoes that should be further explored. PMID:27409772

Nest Bacterial Environment Affects Microbiome of Hoopoe Eggshells, but Not That of the Uropygial Secretion.

PubMed

Martínez-García, Ángela; Martín-Vivaldi, Manuel; Rodríguez-Ruano, Sonia M; Peralta-Sánchez, Juan Manuel; Valdivia, Eva; Soler, Juan J

2016-01-01

The study of associations between symbiotic bacterial communities of hosts and those of surrounding environments would help to understand how bacterial assemblages are acquired, and how they are transmitted from one to another location (i.e. symbiotic bacteria acquisition by hosts). Hoopoes (Upupa epops) smear their eggshells with uropygial secretion (oily secretion produced in their uropygial gland) that harbors antibiotic producing bacteria. Trying to elucidate a possible role of nest material and cloaca microbiota in determining the bacterial community of the uropygial gland and the eggshells of hoopoes, we characterized bacterial communities of nest material, cloaca, uropygial gland and eggshells by the ARISA fingerprinting. Further, by adding material with scarce bacteria and antimicrobial properties, we manipulated the bacterial community of nest material and thus tested experimentally its effects on the microbiomes of the uropygial secretion and of the eggshells. The experiment did not influence the microbiome of the uropygial secretion of females, but affected the community established on eggshells. This is the first experimental evidence indicating that nest material influences the bacterial community of the eggshells and, therefore, probability of embryo infection. Some of the bacterial strains detected in the secretion were also in the bacterial communities of the nest material and of cloaca, but their occurrence within nests was not associated, which suggests that bacterial environments of nest material and cloaca are not sources of symbiotic bacteria for the gland. These results do not support a role of nest environments of hoopoes as reservoirs of symbiotic bacteria. We discuss possible scenarios explaining bacterial acquisition by hoopoes that should be further explored.

Description of adults, eggshells, nestling, fledgling, and nest of the poo-uli

USGS Publications Warehouse

Engilis, A.; Pratt, T.K.; Kepler, C.B.; Ecton, A.M.; Fluetsch, K.M.

1996-01-01

The Poo-uli (Melamprosops phaeosoma), a Hawaiian honeycreeper discovered on the island of Maui in 1973 and now near extinction, is represented in museums by only two specimens. Based on the first observations of a nesting pair and re-examination of the two specimens, we describe the adult male and female, eggshells, nestling, and fledgling Poo-uli. Poo-uli are sexually monochromatic but males are brighter. The male is brown above, whitish below, and has an extensive black mask bordered with gray on the crown and a distinct white auricular patch. The female differs in having a similar facial pattern not as sharply demarked and in having a grayish wash below. The observed fledgling resembled the adults but was paler brown above and whitish below and had a much smaller black mask and pale mandible. We tentatively assigned both museum specimens to first basic plumage because they resembled the adult female but retained some pale juvenal coloration in the mandible. We also determined from dissection that the holotype was an immature male; we could not determine sex of the paratype. The nest was an open cup of twigs and bryophytes with a thin lining of fern rootlets. The nest contained eggshell fragments with brown-gray speckling against a whitish background. The nests, eggshells, and nestlings resemble those of other Hawaiian honeycreepers.

Effect of spatial resolution of soil data on predictions of eggshell trace element levels in the Rook Corvus frugilegus.

PubMed

Orłowski, Grzegorz; Siebielec, Grzegorz; Kasprzykowski, Zbigniew; Dobicki, Wojciech; Pokorny, Przemysław; Wuczyński, Andrzej; Polechoński, Ryszard; Mazgajski, Tomasz D

2016-12-01

Although a considerable research effort has gone into studying the dietary pathways of metals to the bodies of laying female birds and their eggs in recent years, no detailed investigations have yet been carried out relating the properties of the biogeochemical environment at large spatial scales to eggshell trace element levels in typical soil-invertebrate feeding birds under natural conditions. We used data from a large-scale nationwide monitoring survey of soil quality in Poland (3724 sampling points from the 43 792 available) to predict levels of five trace elements (copper [Cu], cadmium [Cd], nickel [Ni], zinc [Zn] and lead [Pb]) in Rook Corvus frugilegus eggshells from 42 breeding colonies. Our major aim was to test whether differences exist in the explanatory power of soil data (acidity, content of elements and organic matter, and particle size) used as a correlate of concentrations of eggshell trace elements among four different distances (5, 10, 15 and 20 km) around rookeries. Over all four distances around the rookeries only the concentrations of Cu and Cd in eggshells were positively correlated with those in soil, while eggshell Pb was correlated with the soil Pb level at the two longest distances (15 and 20 km) around the rookeries. The physical properties of soil (primarily the increase in pH) adversely affected eggshell Cd and Pb concentrations. The patterns and factors governing metal bioaccumulation in soil invertebrates and eggshells appear to be coincident, which strongly suggests a general similarity in the biochemical pathways of elements at different levels of the food web. The increasing acidification of arable soil as a result of excessive fertilisation and over-nitrification can enhance the bioavailability of toxic elements to laying females and their eggs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Immobilisation of lead and zinc in contaminated soil using compost derived from industrial eggshell.

PubMed

Soares, Micaela A R; Quina, Margarida J; Quinta-Ferreira, Rosa M

2015-12-01

This study aims to evaluate the capacity of a compost obtained by co-composting of industrial eggshell (CES) to immobilise lead (Pb) and zinc (Zn) in an acidic soil contaminated by mining activities. Mature compost without eggshell (CWES) and natural eggshell (ES) were also tested as soil amendments for comparison purposes. Three different application rates were used for each material, ensuring the same quantity in terms of neutralizing capacity. Incubation experiments were conducted under controlled conditions and CO2 emissions monitored for 94 days. The environmental availability of Pb and Zn in the amended soil was assessed and bioassays were performed at the end of the incubation period. When eggshells were present, the CES compost raised the soil pH to values higher than 6 and reduced the soil mobile fraction for both Pb and Zn, in more than 95%. Soil toxicity towards Vibrio fischeri was also suppressed and environmental risk decreased to "low level". However, the immobilisation in the acid insoluble soil component was significantly achieved only for Zn. In addition, regarding soil carbon dynamics the CO2-C emissions were enhanced, mainly in the case of the highest rate of amendment. Both first order-E and parallel first order models may adequately describe the kinetic data of CO2-C cumulative release. Without eggshells, the CWES compost revealed limited effect on heavy metals immobilisation, likely due to its small capacity to correct soil acidity, at lower application rates. Using solely eggshells, the ES waste had similar outcomes when compared with CES, but at the higher application rate, CO2 emissions were enhanced with the eggshell compost due to the contribution of biotic carbon present therein. Therefore, this study points out that CES is an effective liming material and may be used for in situ remediation of contaminated soil with Pb and Zn. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of mean cell residence time on transmembrane flux, mixed-liquor characteristics and overall performance of a submerged anaerobic membrane bioreactor.

PubMed

Pacheco-Ruiz, Santiago; Heaven, Sonia; Banks, Charles J

2017-05-01

Kinetic control of Mean Cell Residence Time (MCRT) was shown to have a significant impact on membrane flux under steady-state conditions. Two laboratory-scale flat-plate submerged anaerobic membrane bioreactors were operated for 245 days on a low-to-intermediate strength substrate with high suspended solids. Transmembrane pressure was maintained at 2.2 kPa throughout four experimental phases, while MCRT in one reactor was progressively reduced. This allowed very accurate measurement of sustainable membrane flux rates at different MCRTs, and hence the degree of membrane fouling. Performance data were gathered on chemical oxygen demand (COD) removal efficiency, and a COD mass balance was constructed accounting for carbon converted into new biomass and that lost in the effluent as dissolved methane. Measurements of growth yield at each MCRT were made, with physical characterisation of each mixed liquor based on capillary suction time. The results showed membrane flux and MLSS filterability was highest at short MCRT, although specific methane production (SMP) was lower since a proportion of COD removal was accounted for by higher biomass yield. There was no advantage in operating at an MCRT <25 days. When considering the most suitable MCRT there is thus a trade-off between membrane performance, SMP and waste sludge yield.

Proton conducting ceramic membranes for hydrogen separation

DOEpatents

Elangovan, S [South Jordan, UT; Nair, Balakrishnan G [Sandy, UT; Small, Troy [Midvale, UT; Heck, Brian [Salt Lake City, UT

2011-09-06

A multi-phase proton conducting material comprising a proton-conducting ceramic phase and a stabilizing ceramic phase. Under the presence of a partial pressure gradient of hydrogen across the membrane or under the influence of an electrical potential, a membrane fabricated with this material selectively transports hydrogen ions through the proton conducting phase, which results in ultrahigh purity hydrogen permeation through the membrane. The stabilizing ceramic phase may be substantially structurally and chemically identical to at least one product of a reaction between the proton conducting phase and at least one expected gas under operating conditions of a membrane fabricated using the material. In a barium cerate-based proton conducting membrane, one stabilizing phase is ceria.

Effect of storage duration on the rheological properties of goose liquid egg products and eggshell membranes.

PubMed

Kumbar, V; Nedomova, S; Trnka, J; Buchar, J; Pytel, R

2016-07-01

In practice, goose eggs are increasingly used and, therefore, the rheological properties have to be known for processing. The eggs of geese (Landes Goose, Anser anser f. domestica) were stored for one, 2, 3, 4, 6, and 8 wk at a constant temperature 4°C. First of all, the egg quality parameters were described in terms of egg weight, egg weight loss, egg shape index, yolk height, albumen height, yolk index, albumen index, and Haugh units. In the next step the rheological behavior of liquid egg products (egg yolk, albumen, and whole liquid egg) was studied using a concentric cylinder viscometer. Flow curves of all liquid egg products exhibited non-Newtonian shear thinning behavior. This behavior can be described using the Herschel-Bulkley model and for technical application using the Ostwald-de Waele model. The effect of the storage duration on the rheological behavior is different for the different liquid egg products. With the exception of very low shear rates, the viscosity of the egg yolk as well as of the whole liquid egg decreases with storage time. At lower shear rates there is a tendency toward increased albumen viscosity with storage duration. The storage duration also affects the mechanical properties of the eggshell membrane. This effect has been evaluated in terms of the ultimate tensile strength, fracture strain, and fracture toughness. All these parameters increased with the loading rate, but decreased during the egg storage. These mechanical phenomena should be respected, namely in the design of the egg model for the numerical simulation of the egg behavior under different kinds of the mechanical loading. © 2016 Poultry Science Association Inc.

Functionalized nanoparticles based solid-phase membrane micro-tip extraction and high-performance liquid chromatography analyses of vitamin B complex in human plasma.

PubMed

Ali, Imran; Kulsum, Umma; Al-Othman, Zeid A; Alwarthan, Abdulrahman; Saleem, Kishwar

2016-07-01

Iron nanoparticles were prepared by a green method following functionalization using 1-butyl-3-methylimidazolium bromide. 1-Butyl-3-methylimidazole iron nanoparticles were characterized using FTIR spectroscopy, energy dispersive X-ray fluorescence, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The nanoparticles were used in solid-phase membrane micro-tip extraction to separate vitamin B complex from plasma before high-performance liquid chromatography. The optimum conditions obtained were sorbent (15 mg), agitation time (30 min), pH (9.0), desorbing solvent [water (5 mL) + methanol (5 mL) + sodium hydroxide (0.1 N) + acetic acid (d = 1.05 kg/L, pH 5.5), desorbing volume (10 mL) and desorption time (30 min). The percentage recoveries of all the eight vitamin B complex were from 60 to 83%. A high-performance liquid chromatography method was developed using a PhE column (250 × 4.6 mm, 5.0 μm) and water/acetonitrile (95:5, v/v; pH 4.0 with 0.1% formic acid) mobile phase. The flow rate was 1.0 mL/min with detection at 270 and 210 nm. The values of the capacity, separation and resolution factor were 0.57-39.47, 1.12-6.00 and 1.84-26.26, respectively. The developed sample preparation and chromatographic methods were fast, selective, inexpensive, economic and reproducible. The developed method can be applied for analyzing these drugs in biological and environmental matrices. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rapid, specific determination of iodine and iodide by combined solid-phase extraction/diffuse reflectance spectroscopy

NASA Technical Reports Server (NTRS)

Arena, Matteo P.; Porter, Marc D.; Fritz, James S.

2002-01-01

A new, rapid methodology for trace analysis using solid-phase extraction is described. The two-step methodology is based on the concentration of an analyte onto a membrane disk and on the determination by diffuse reflectance spectroscopy of the amount of analyte extracted on the disk surface. This method, which is adaptable to a wide range of analytes, has been used for monitoring ppm levels of iodine and iodide in spacecraft water. Iodine is used as a biocide in spacecraft water. For these determinations, a water sample is passed through a membrane disk by means of a 10-mL syringe that is attached to a disk holder assembly. The disk, which is a polystyrene-divinylbenzene composite, is impregnated with poly(vinylpyrrolidone) (PVP), which exhaustively concentrates iodine as a yellow iodine-PVP complex. The amount of concentrated iodine is then determined in only 2 s by using a hand-held diffuse reflectance spectrometer by comparing the result with a calibration curve based on the Kubelka-Munk function. The same general procedure can be used to determine iodide levels after its facile and exhaustive oxidation to iodine by peroxymonosulfate (i.e., Oxone reagent). For samples containing both analytes, a two-step procedure can be used in which the iodide concentration is calculated from the difference in iodine levels before and after treatment of the sample with peroxymonosulfate. With this methodology, iodine and iodide levels in the 0.1-5.0 ppm range can be determined with a total workup time of approximately 60 s with a RSD of approximately 6%.

Comparing the Accumulation of PCBs by Passive Samplers and Mussels from the Water Column at a Contaminated Sediment Site

EPA Science Inventory

Passive samplers, including semi-permeable membrane devices (SPMDs), solid phase microextraction (SPME) and polyethylene devices (PEDs), provide innovative tools for measuring hydrophobic organic contaminants (HOCs) originating from contaminated waters and sediments. Because the...

Eggshell ultrastructure and delivery of pharmacological inhibitors to the early embryo of R. prolixus by ethanol permeabilization of the extraembryonic layers.

PubMed

Bomfim, Larissa; Vieira, Priscila; Fonseca, Ariene; Ramos, Isabela

2017-01-01

Most vectors of arthropod-borne diseases produce large eggs with hard and opaque eggshells. In several species, it is still not possible to induce molecular perturbations to the embryo by delivery of molecules using microinjections or eggshell permeabilization without losing embryo viability, which impairs basic studies regarding development and population control. Here we tested the properties and permeability of the eggshell of R. prolixus, a Chagas disease vector, with the aim to deliver pharmacological inhibitors to the egg cytoplasm and allow controlled molecular changes to the embryo. Using field emission scanning and transmission electron microscopy we found that R. prolixus egg is coated by three main layers: exochorion, vitelline layer and the plasma membrane, and that the pores that allow gas exchange (aeropiles) have an average diameter of 10 μm and are found in the rim of the operculum at the anterior pole of the egg. We tested if different solvents could permeate through the aeropiles and reach the egg cytoplasm/embryo and found that immersions of the eggs in ethanol lead to its prompt penetration through the aeropiles. A single five minute-immersion of the eggs/embryos in pharmacological inhibitors, such as azide, cyanide and cycloheximide, solubilized in ethanol resulted in impairment of embryogenesis in a dose dependent manner and DAPI-ethanol solutions were also able to label the embryo cells, showing that ethanol penetration was able to deliver those molecules to the embryo cells. Multiple immersions of the embryo in the same solutions increased the effect and tests using bafilomycin A1 and Pepstatin A, known inhibitors of the yolk proteolysis, were also able to impair embryogenesis and the yolk protein degradation. Additionally, we found that ethanol pre-treatments of the egg make the aeropiles more permeable to aqueous solutions, so drugs diluted in water can be carried after the eggs are pre-treated with ethanol. Thus, we found that delivery of pharmacological inhibitors to the embryo of R. prolixus can be performed simply by submersing the fertilized eggs in ethanol with no need for additional methods such as microinjections or electroporation. We discuss the potential importance of this methodology to the study of this vector developmental biology and population control.

Engineering the Membrane/Electrode Interface To Improve the Performance of Solid-State Supercapacitors.

PubMed

Huang, Chun; Zhang, Jin; Snaith, Henry J; Grant, Patrick S

2016-08-17

This paper investigates the effect of adding a 450 nm layer based on porous TiO2 at the interface between a 4.5 μm carbon/TiO2 nanoparticle-based electrode and a polymer electrolyte membrane as a route to improve energy storage performance in solid-state supercapacitors. Electrochemical characterization showed that adding the interface layer reduced charge transfer resistance, promoted more efficient ion transfer across the interface, and significantly improved charge/discharge dynamics in a solid-state supercapacitor, resulting in an increased areal capacitance from 45.3 to 111.1 mF cm(-2) per electrode at 0.4 mA cm(-2).

Clumped isotope paleothermometry of eggshells as an indicator of vertebrate endothermy

NASA Astrophysics Data System (ADS)

Canavan, R. R.; Field, D. J.; Therrien, F.; Zelenitsky, D.; Affek, H. P.

2014-12-01

Isotopic analyses of the calcite or aragonite shells of aquatic organisms are often used in the study of the environmental conditions in which they grow; however, this approach is less straightforward in the terrestrial realm, where environments may be more heterogeneous. In such terrestrial localities, the bioapatite of vertebrate teeth comprises the typical archival material for isotopic analyses. The calcitic eggshells of birds and other reptiles may provide suitable material for isotopic analyses that are aimed at studying their physiology and ecology. Here we apply a novel thermometer, carbonate clumped isotopes (Δ47), to test for endothermy in extinct non-avian dinosaurs in the context provided by eggs of modern reptiles and birds. These Δ47-derived temperatures should reflect the temperature of shell formation, which in endothermic animals such as birds should represent the mother's internal body temperature. In ectothermic animals, the same is true although their body temperatures are more affected by the external environment and thus Δ47 temperatures could more accurately describe local environmental temperatures during eggshell formation. Fossil eggshells represent appropriate material for reconstructing internal body temperatures of extinct non-avian dinosaurs since they mineralized within the mother's body, and fragments of eggshell are commonly recovered from dinosaur-bearing fossil deposits. The dimensions of these fragments provide sufficient material for the relatively large sample required for clumped isotope analysis (~20mg). Fossil eggshell samples from several taxa of Late Cretaceous non-avian dinosaurs were analyzed using Δ47 paleothermometry. Textural inspection was used as a first test for diagenetic alteration of the original calcite, and histological indicators were used for broad taxonomic identifications. Preliminary results of Δ47-derived body temperature estimates from eggshells are consistent with previous body temperatures estimates from bioapatite Δ47 analyses performed on non-avian dinosaur teeth.

Heavy metal immobilization in soil near abandoned mines using eggshell waste and rapeseed residue.

PubMed

Lee, Sang Soo; Lim, Jung Eun; El-Azeem, Samy A M Abd; Choi, Bongsu; Oh, Sang-Eun; Moon, Deok Hyun; Ok, Yong Sik

2013-03-01

Heavy metal contamination of agricultural soils has received great concern due to potential risk to human health. Cadmium and Pb are largely released from abandoned or closed mines in Korea, resulting in soil contamination. The objective of this study was to evaluate the effects of eggshell waste in combination with the conventional nitrogen, phosphorous, and potassium fertilizer (also known as NPK fertilizer) or the rapeseed residue on immobilization of Cd and Pb in the rice paddy soil. Cadmium and Pb extractabilities were tested using two methods of (1) the toxicity characteristics leaching procedure (TCLP) and (2) the 0.1 M HCl extraction. With 5 % eggshell addition, the values of soil pH were increased from 6.33 and 6.51 to 8.15 and 8.04 in combination with NPK fertilizer and rapeseed residue, respectively, compared to no eggshell addition. The increase in soil pH may contribute to heavy metal immobilization by altering heavy metals into more stable in soils. Concentrations of TCLP-extracted Cd and Pb were reduced by up to 67.9 and 93.2 % by addition of 5 % eggshell compared to control. For 0.1 M HCl extraction method, the concentration of 0.1 M HCl-Cd in soils treated with NPK fertilizer and rapeseed residue was significantly reduced by up to 34.01 and 46.1 %, respectively, with 5 % eggshell addition compared to control. A decrease in acid phosphatase activity and an increase in alkaline phosphatase activity at high soil pH were also observed. Combined application of eggshell waste and rapeseed residue can be cost-effective and beneficial way to remediate the soil contaminated with heavy metals.

'All-solid-state' electrochemistry of a protein-confined polymer electrolyte film

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

Parthasarathy, Meera; Pillai, Vijayamohanan K.; Mulla, Imtiaz S.

2007-12-07

Interfacial redox behavior of a heme protein (hemoglobin) confined in a solid polymer electrolyte membrane, Nafion (a perfluoro sulfonic acid ionomer) is investigated using a unique 'all-solid-state' electrochemical methodology. The supple phase-separated structure of the polymer electrolyte membrane, with hydrophilic pools containing solvated protons and water molecules, is found to preserve the incorporated protein in its active form even in the solid-state, using UV-visible, Fluorescence (of Tryptophan and Tyrosine residues) and DRIFT (diffuse reflectance infrared Fourier transform) spectroscopy. More specifically, solid-state cyclic voltammetry and electrochemical impedance of the protein-incorporated polymer films reveal that the Fe{sup 2+}-form of the entrapped proteinmore » is found to bind molecular oxygen more strongly than the native protein. In the 'all-solid-state' methodology, as there is no need to dip the protein-modified electrode in a liquid electrolyte (like the conventional electrochemical methods), it offers an easier means to study a number of proteins in a variety of polymer matrices (even biomimetic assemblies). In addition, the results of the present investigation could find interesting application in a variety of research disciplines, in addition to its fundamental scientific interest, including protein biotechnology, pharmaceutical and biomimetic chemistry.« less

Solid state proton and electron mediating membrane and use in catalytic membrane reactors

DOEpatents

White, James H.; Schwartz, Michael; Sammells, Anthony F.

1998-01-01

This invention provides catalytic proton and electron mediating membranes useful in catalytic reactors. The membranes have an oxidation and a reduction surface and comprise a single-phase mixed metal oxide material of the formula: AB.sub.1-x B'.sub.x O.sub.3-y wherein A is selected from Ca, Sr or Ba ions; B is selected from Ce, Tb, Pr, or Th ions; B' is selected from Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Al, Ga, or In ions, or combinations thereof; and x is greater than or equal to 0.02 and less than or equal to 0.5. The membranes can further comprise a catalyst on either the oxidation or reduction surface, or both. Membranes include those which are fabricated-by combining powders of metal oxides or metal carbonates of metal A ion, metal B ion and metal B' ion such that the stoichiometric ratio A:B:B' is 1:1-x:x where 0.2.ltoreq..times.0.5, repeatedly calcining and milling the combined powders until a single-phase material is obtained and pressing and sintering the singlephase material to obtain a membrane.

Two new ootaxa from the late Jurassic: The oldest record of crocodylomorph eggs, from the Lourinhã Formation, Portugal

PubMed Central

Mateus, Octávio; Marzola, Marco; Balbino, Ausenda

2017-01-01

The Late Jurassic Lourinhã Formation is known for its abundant remains of dinosaurs, crocodylomorphs and other vertebrates. Among this record are nine localities that have produced either dinosaur embryos, eggs or eggshell fragments. Herein, we describe and identify the first crocodiloid morphotype eggs and eggshells from the Lourinhã Formation, from five occurrences. One clutch from Cambelas, composed of 13 eggs, eggshell fragments from Casal da Rola and Peralta, one crushed egg and eggshells from Paimogo North, and four crushed eggs as well as eggshell fragments from Paimogo South. We observed and confirmed diagnostic morphological characters for crocodiloid eggshells and which are consistent with a crocodylomorph affinity, such as the ellipsoidal shape, wedge-shaped shell units, triangular extinction under cross-polarized light, and tabular ultrastructure. This material is distinctive enough to propose two new ootaxa within the oofamily Krokolithidae, Suchoolithus portucalensis, oogen. and oosp. nov., for the material from Cambelas, the most complete clutch known for crocodiloid eggs, and Krokolithes dinophilus, oosp. nov., for the remaining material. These are the oldest crocodylomorph eggs known, extending the fossil record for this group to the Late Jurassic. Furthermore, except for the clutch from Cambelas, the material was found with theropod eggs and nests, in the other four occurrences, which seem to suggest some form of biological relationship, still unclear at this point. PMID:28273086

Estimation of genetic parameters related to eggshell strength using random regression models.

PubMed

Guo, J; Ma, M; Qu, L; Shen, M; Dou, T; Wang, K

2015-01-01

This study examined the changes in eggshell strength and the genetic parameters related to this trait throughout a hen's laying life using random regression. The data were collected from a crossbred population between 2011 and 2014, where the eggshell strength was determined repeatedly for 2260 hens. Using random regression models (RRMs), several Legendre polynomials were employed to estimate the fixed, direct genetic and permanent environment effects. The residual effects were treated as independently distributed with heterogeneous variance for each test week. The direct genetic variance was included with second-order Legendre polynomials and the permanent environment with third-order Legendre polynomials. The heritability of eggshell strength ranged from 0.26 to 0.43, the repeatability ranged between 0.47 and 0.69, and the estimated genetic correlations between test weeks was high at > 0.67. The first eigenvalue of the genetic covariance matrix accounted for about 97% of the sum of all the eigenvalues. The flexibility and statistical power of RRM suggest that this model could be an effective method to improve eggshell quality and to reduce losses due to cracked eggs in a breeding plan.

The evolution of eggshell cuticle in relation to nesting ecology

PubMed Central

Hauber, Mark E.

2016-01-01

Avian eggs are at risk of microbial infection prior to and during incubation. A large number of defence mechanisms have evolved in response to the severe costs imposed by these infections. The eggshell's cuticle is an important component of antimicrobial defence, and its role in preventing contamination by microorganisms in domestic chickens is well known. Nanometer-scale cuticular spheres that reduce microbial attachment and penetration have recently been identified on eggs of several wild avian species. However, whether these spheres have evolved specifically for antimicrobial defence is unknown. Here, we use comparative data on eggshell cuticular structure and nesting ecology to test the hypothesis that birds nesting in habitats with higher risk of infection (e.g. wetter and warmer) are more likely to evolve cuticular nanospheres on their eggshells than those nesting in less risky habitats. We found that nanostructuring, present in 54 of 296 analysed species, is the ancestral condition of avian eggshells and has been retained more often in taxa that nest in humid infection-prone environments, suggesting that they serve critical roles in antimicrobial egg defence. PMID:27488648

The evolution of eggshell cuticle in relation to nesting ecology.

PubMed

D'Alba, Liliana; Maia, Rafael; Hauber, Mark E; Shawkey, Matthew D

2016-08-17

Avian eggs are at risk of microbial infection prior to and during incubation. A large number of defence mechanisms have evolved in response to the severe costs imposed by these infections. The eggshell's cuticle is an important component of antimicrobial defence, and its role in preventing contamination by microorganisms in domestic chickens is well known. Nanometer-scale cuticular spheres that reduce microbial attachment and penetration have recently been identified on eggs of several wild avian species. However, whether these spheres have evolved specifically for antimicrobial defence is unknown. Here, we use comparative data on eggshell cuticular structure and nesting ecology to test the hypothesis that birds nesting in habitats with higher risk of infection (e.g. wetter and warmer) are more likely to evolve cuticular nanospheres on their eggshells than those nesting in less risky habitats. We found that nanostructuring, present in 54 of 296 analysed species, is the ancestral condition of avian eggshells and has been retained more often in taxa that nest in humid infection-prone environments, suggesting that they serve critical roles in antimicrobial egg defence. © 2016 The Author(s).

Assessment the levels of tartrate-resistant acid phosphatase (TRAP) on mice fed with eggshell calcium citrate malate.

PubMed

Yu, Yiding; Zhang, Mingdi; Lin, Songyi; Wang, Liyan; Liu, Jingbo; Jones, Gregory; Huang, Hsiang-Chi

2013-07-01

Optimized conditions were obtained by one-factor-at-a-time test (OFAT) and ternary quadratic regression orthogonal composite design (TQROCD) respectively. By pulse electric fields (PEF) technology, the process of eggshell calcium citrate malate (ESCCM), eggshell calcium citrate (ESCC) and eggshells calcium malate (ESCM) were comprehensive compared. The levels of tartrate-resistant acid phosphatase (TRAP) and the bioavailability on mice fed with eggshell calcium citrate malate (ESCCM) treated by pulsed electric field (PEF) were evaluated. Results showed that the rates of calcium dissolution of the different acids studied can be arranged as ESCCM (7.90 mg/mL)>ESCC (7.12 mg/mL)>ESCM (7.08 mg/mL) from highest to lowest rate of dissolution. At the same dose 133.0 mg kg(-1) d(-1), the levels of TRAP in the ESCCM treatment groups were significantly lower than those in ESCM and ESCC (P<0.05). Bone calcium content in the mice fed with ESCCM was generally higher than fed with ESCM and ESCC. Copyright © 2013 Elsevier B.V. All rights reserved.

Inoculation onto solid surfaces protects Salmonella spp. during acid challenge: a model study using polyethersulfone membranes.

PubMed

Gawande, Purushottam V; Bhagwat, Arvind A

2002-01-01

Salmonellae are the most frequently reported cause of outbreaks of food-borne gastroenteritis in the United States. In clinical trials, the oral infective dose (ID) for healthy volunteers was estimated to be approximately 1 million cells. However, in reports from various outbreaks, the ID of Salmonella species associated with solid foods was estimated to be as few as 100 cells. We found that fresh-cut produce surfaces not only provided suitable solid support for pathogen attachment but also played a critical role in increasing the acid tolerance of the pathogen. However the acidic nature of certain produce played no role in making salmonellae resistant to stomach acidity. Inoculation onto fresh-cut produce surfaces, as well as onto inert surfaces, such as polyethersulfone membranes and tissue paper, increased the survival of salmonellae during acid challenge (50 mM Na-citrate, pH 3.0; 37 degrees C; 2 h) by 4 to 5 log units. Acid challenge experiments using cells inoculated onto polyethersulfone membranes provided a model system suitable for studying the underlying fundamentals of the protection that occurs when Salmonella strains are associated with solid foods. The surface-associated acid protection, which was observed in several Salmonella strains, required de novo protein synthesis and was independent of stationary-phase sigma transcription factor.

Inoculation onto Solid Surfaces Protects Salmonella spp. during Acid Challenge: a Model Study Using Polyethersulfone Membranes

PubMed Central

Gawande, Purushottam V.; Bhagwat, Arvind A.

2002-01-01

Salmonellae are the most frequently reported cause of outbreaks of food-borne gastroenteritis in the United States. In clinical trials, the oral infective dose (ID) for healthy volunteers was estimated to be approximately 1 million cells. However, in reports from various outbreaks, the ID of Salmonella species associated with solid foods was estimated to be as few as 100 cells. We found that fresh-cut produce surfaces not only provided suitable solid support for pathogen attachment but also played a critical role in increasing the acid tolerance of the pathogen. However the acidic nature of certain produce played no role in making salmonellae resistant to stomach acidity. Inoculation onto fresh-cut produce surfaces, as well as onto inert surfaces, such as polyethersulfone membranes and tissue paper, increased the survival of salmonellae during acid challenge (50 mM Na-citrate, pH 3.0; 37°C; 2 h) by 4 to 5 log units. Acid challenge experiments using cells inoculated onto polyethersulfone membranes provided a model system suitable for studying the underlying fundamentals of the protection that occurs when Salmonella strains are associated with solid foods. The surface-associated acid protection, which was observed in several Salmonella strains, required de novo protein synthesis and was independent of stationary-phase sigma transcription factor. PMID:11772613

Induced molt using cassava meal. 2. Effects on eggshell quality, ultrastructure, and pore density in late-phase laying hens.

PubMed

Gongruttananun, N

2018-03-01

This experiment was conducted to investigate the effect of a non-fasting induced molt using cassava meal on the eggshell quality, ultrastructure, and porosity in late-phase (74 wk old) H&N Brown laying hens. Hens were randomly assigned to 3 treatments of 90 birds each: 1) Controls with no induced molt (CONT); 2) molted by full feeding with cassava meal for 3 wk (FP3); and 3) molted by full feeding with cassava meal for 4 wk (FP4). Following the treatments, groups 2 and 3 were fed a pullet developer diet for 3 weeks. During the molt period, the birds were exposed to an 8L:16D photoperiod and had access to drinking water at all times. Thereafter, all hens were fed a layer diet (17% CP) and exposed to a 16L:8D photoperiod until the end of the study. Compared to the CONT treatment, significant reductions (P < 0.05) in shell weight, thickness, and breaking strength were identified on the sixth d of feeding the molt diet. Significant (P < 0.05) improvements in these parameters were observed for the FP3 and FP4 treatments during the post-molt period, with the greater degree in the FP4 treatment. In addition, scanning electron microscopy revealed a smaller size of mammillary knobs accompanied by a higher density of mammillae in eggs taken from the molted treatments. Evidence of type B mammillae was detected in an egg produced by the CONT hens, whereas confluent and cuffing mammillae were observed in an egg taken from the FP4 birds. Reduced pore densities were found in the molted treatments in some periods of the post-molt production as compared to the CONT treatment. It was concluded that feeding the cassava molt diet for 4 wk could be an effective non-fasting molt method for improving eggshell quality, ultrastructure, and porosity in post-molt laying hens.

Ultrasonic-assisted preparation of nano eggshell powder: a novel catalyst in green and high efficient synthesis of 2-aminochromenes.

PubMed

Mosaddegh, Elaheh

2013-11-01

The nano eggshell powder (NESP) has been prepared by ultrasound irradiation and used as a novel and biodegradable catalyst with high catalytic activity and reusability in green synthesis of 2-aminochromenes via condensation of α- or β-phathol, malononitrile and aromatic aldehydes at 120 °C under solvent-free conditions. The reaction proceeds to completion within 10-35 min in 91-98% yield. Nano eggshell catalyst was characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and X-ray fluorescence, thermal gravimetric, surface area and elemental analyses. In addition, the catalytic activity and chemical structure of nano-sized eggshell were compared with pure CaCO3. Copyright © 2013 Elsevier B.V. All rights reserved.

CeO2-Y2O3-ZrO2 Membrane with Enhanced Molten Salt Corrosion Resistance for Solid Oxide Membrane (SOM) Electrolysis Process

NASA Astrophysics Data System (ADS)

Zou, Xingli; Li, Xin; Shen, Bin; Lu, Xionggang; Xu, Qian; Zhou, Zhongfu; Ding, Weizhong

2017-02-01

Innovative CeO2-Y2O3-ZrO2 membrane has been successfully developed and used in the solid oxide membrane (SOM) electrolysis process for green metallic materials production. The x mol pct ceria/(8- x) mol pct yttria-costabilized zirconia ( xCe(8- x)YSZ, x = 0, 1, 4, or 7) membranes have been fabricated and investigated as the membrane-based inert anodes to control the SOM electroreduction process in molten salt. The characteristics of these fabricated xCe(8- x)YSZ membranes including their corrosion resistances in molten salt and their degradation mechanisms have been systematically investigated and compared. The results show that the addition of ceria in the YSZ-based membrane can inhibit the depletion of yttrium during the SOM electrolysis, which thus makes the ceria-reinforced YSZ-based membranes possess enhanced corrosion resistances to molten salt. The ceria/yttria-costabilized zirconia membranes can also provide reasonable oxygen ion conductivity during electrolysis. Further investigation shows that the newly modified 4Ce4YSZ ceramic membrane has the potential to be used as novel inert SOM anode for the facile and sustainable production of metals/alloys/composites materials such as Si, Ti5Si3, TiC, and Ti5Si3/TiC from their metal oxides precursors in molten CaCl2.

Evaluation of graphene-based sorbent in the determination of polar environmental contaminants in water by micro-solid phase extraction-high performance liquid chromatography.

PubMed

Naing, Nyi Nyi; Li, Sam Fong Yau; Lee, Hian Kee

2016-01-04

A facile method of extraction using porous membrane protected micro-solid phase extraction (μ-SPE) with a graphene-based sorbent followed by high performance liquid chromatography-ultraviolet detector was developed. The reduced graphene oxide (r-GO) (1mg), synthesized from graphite oxide, was enclosed in a polypropylene bag representing the μ-SPE device, which was used for the extraction of estrogens such as estrone, 17β-estradiol, 17α-ethynylestradiol and diethylstilbestrol in water. The r-GO obtained was identified and characterized by Fourier transform infrared, transmission electron microscopy, scanning electron microscopy and thermogravimetric analysis. The sorbent was loaded with sodium dodecyl sulfate by sonication to prevent agglomeration in aqueous solution. With this method, low limits of detection of between 0.24 and 0.52 ng L(-1) were achieved. For estrogen analysis a linear calibration range of 0.01-100 μg L(-1) was obtained, with the coefficients of determination (r(2)) higher than 0.992. This proposed method was successfully applied to determine estrogens in water. Copyright © 2015 Elsevier B.V. All rights reserved.

Higher Storage Temperature Causes Greater Salmonella enterica Serovar Typhimurium Internal Penetration of Artificially Contaminated, Commercially Available, Washed Free Range Eggs.

PubMed

Whiley, Alice; Fallowfield, Howard; Ross, Kirstin; McEvoy, Vanessa; Whiley, Harriet

2016-07-01

Foodborne salmonellosis is a major public health concern, with contaminated eggs identified as a significant source of infection. In Australia, the most prevalent cause of salmonellosis from eggs is Salmonella enterica subsp. enterica serovar Typhimurium. This study explored the effect of temperature after 1, 7, 14, 21, and 28 days of storage on commercially available washed free range eggs, artificially contaminated with Salmonella Typhimurium on the external surface. At each time point, the external surface of the egg, the crushed eggshell, and the internal egg yolk and albumen were analyzed for Salmonella. After 28 days of storage, 25% of eggs stored at 4°C, 50% of eggs stored at 14°C, and 100% of eggs stored at 23 and 35°C were internally contaminated with Salmonella. After 1 day of storage, more than 50% of all eggs had Salmonella present in the crushed shell after the external surface had been disinfected with ethanol. This is the first study to demonstrate that refrigeration reduced the potential for Salmonella Typhimurium to penetrate the eggshell membrane and internally contaminate table eggs commercially available in Australia. It also suggests that the processes of cracking eggs may be a source of cross-contamination within the kitchen.

Electrochemical performance and durability of carbon supported Pt catalyst in contact with aqueous and polymeric proton conductors.

PubMed

Andersen, Shuang Ma; Skou, Eivind

2014-10-08

Significant differences in catalyst performance and durability are often observed between the use of a liquid electrolyte (e.g., sulfuric acid), and a solid polymer electrolyte (e.g., Nafion). To understand this phenomenon, we studied the electrochemical behavior of a commercially available carbon supported platinum catalyst in four different electrode structures: catalyst powder (CP), catalyst ionomer electrode (CIE), half membrane electrode assembly (HMEA), and full membrane electrode assembly (FMEA) in both ex situ and in situ experiments under a simulated start/stop cycle. We found that the catalyst performance and stability are very much influenced by the presence of the Nafion ionomers. The proton conducting phase provided by the ionomer and the self-assembled electrode structure render the catalysts a higher utilization and better stability. This is probably due to an enhanced dispersion, an improved proton-catalyst interface, the restriction of catalyst particle aggregation, and the improved stability of the ionomer phase especially after the lamination. Therefore, an innovative electrode HMEA design for ex-situ catalyst characterization is proposed. The electrode structure is identical to the one used in a real fuel cell, where the protons transport takes place solely through solid state proton conducting phase.

Inkjet printing of nanoporous gold electrode arrays on cellulose membranes for high-sensitive paper-like electrochemical oxygen sensors using ionic liquid electrolytes.

PubMed

Hu, Chengguo; Bai, Xiaoyun; Wang, Yingkai; Jin, Wei; Zhang, Xuan; Hu, Shengshui

2012-04-17

A simple approach to the mass production of nanoporous gold electrode arrays on cellulose membranes for electrochemical sensing of oxygen using ionic liquid (IL) electrolytes was established. The approach, combining the inkjet printing of gold nanoparticle (GNP) patterns with the self-catalytic growth of these patterns into conducting layers, can fabricate hundreds of self-designed gold arrays on cellulose membranes within several hours using an inexpensive inkjet printer. The resulting paper-based gold electrode arrays (PGEAs) had several unique properties as thin-film sensor platforms, including good conductivity, excellent flexibility, high integration, and low cost. The porous nature of PGEAs also allowed the addition of electrolytes from the back cellulose membrane side and controllably produced large three-phase electrolyte/electrode/gas interfaces at the front electrode side. A novel paper-based solid-state electrochemical oxygen (O(2)) sensor was therefore developed using an IL electrolyte, 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF(6)). The sensor looked like a piece of paper but possessed high sensitivity for O(2) in a linear range from 0.054 to 0.177 v/v %, along with a low detection limit of 0.0075% and a short response time of less than 10 s, foreseeing its promising applications in developing cost-effective and environment-friendly paper-based electrochemical gas sensors.

The biomechanical, chemical and physiological adaptations of the eggs of two Australian megapodes to their nesting strategies and their implications for extinct titanosaur dinosaurs.

PubMed

Grellet-Tinner, G; Lindsay, S; Thompson, M B

2017-08-01

Megapodes are galliform birds endemic to Australasia and unusual among modern birds in that they bury their eggs for incubation in diverse substrates and using various strategies. Alectura lathami and Leipoa ocellata are Australian megapodes that build and nest in mounds of soil and organic matter. Such unusual nesting behaviours have resulted in particular evolutionary adaptations of their eggs and eggshells. We used a combination of scanning electron microscopy, including electron backscatter diffraction and energy-dispersive X-ray spectroscopy, to determine the fine structure of the eggshells and micro-CT scanning to map the structure of pores. We discovered that the surface of the eggshell of A. lathami displays nodes similar to those of extinct titanosaur dinosaurs from Transylvania and Auca Mahuevo egg layer #4. We propose that this pronounced nodular ornamentation is an adaptation to an environment rich in organic acids from their nest mound, protecting the egg surface from chemical etching and leaving the eggshell thickness intact. By contrast, L. ocellata nests in mounds of sand with less organic matter in semiarid environments and has eggshells with weakly defined nodes, like those of extinct titanosaurs from AM L#3 that also lived in a semiarid environment. We suggest the internode spaces in both megapode and titanosaur species act as funnels, which concentrate the condensed water vapour between the nodes. This water funnelling in megapodes through the layer of calcium phosphate reduces the likelihood of bacterial infection by creating a barrier to microbial invasion. In addition, the accessory layer of both species possesses sulphur, which reinforces the calcium phosphate barrier to bacterial and fungal contamination. Like titanosaurs, pores through the eggshell are Y-shaped in both species, but A. lathami displays unique mid-shell connections tangential to the eggshell surface and that connect some adjacent pores, like the eggshells of titanosaur of AM L#4 and Transylvania. The function of these interconnections is not known, but likely helps the diffusion of gases in eggs buried in environments where occlusion of pores is possible. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

Parental conflict and blue egg coloration in a seabird

NASA Astrophysics Data System (ADS)

Morales, Judith; Torres, Roxana; Velando, Alberto

2010-02-01

When both parents provide offspring care, equal sharing of costly parental duties may enhance reproductive success. This is crucial for longlived species, where increased parental effort in current reproduction profoundly affects future reproduction. Indication of reproductive value or willingness to invest in reproduction may promote matching responses by mates, thus reducing the conflict over care. In birds with biparental care, blue-green eggshell color may function as a signal of reproductive value that affects parental effort, as predicted by the signaling hypothesis of blue-green eggshell coloration. However, this hypothesis has not been explored during incubation, when the potential stimulus of egg color is present, and has been little studied in longlived birds. We experimentally studied if egg color affected incubation patterns in the blue-footed booby, a longlived species with biparental care and blue eggs. We exchanged fresh eggs between nests of the same laying date and recorded parental incubation effort on the following 4 days. Although egg color did not affect male effort, original eggshell color was correlated with pair matching in incubation. Exchanged eggshell color did not affect incubation patterns. This suggests that biliverdin-based egg coloration reflects female quality features that are associated with pair incubation effort or that blue-footed boobies mate assortatively high-quality pairs incubating more colorful clutches. An intriguing possibility is that egg coloration facilitates an equal sharing of incubation, the signal being functional only during a short period close to laying. Results also suggest that indication of reproductive value reduces the conflict over care.

Multimodal hard x-ray imaging with resolution approaching 10 nm for studies in material science

NASA Astrophysics Data System (ADS)

Yan, Hanfei; Bouet, Nathalie; Zhou, Juan; Huang, Xiaojing; Nazaretski, Evgeny; Xu, Weihe; Cocco, Alex P.; Chiu, Wilson K. S.; Brinkman, Kyle S.; Chu, Yong S.

2018-03-01

We report multimodal scanning hard x-ray imaging with spatial resolution approaching 10 nm and its application to contemporary studies in the field of material science. The high spatial resolution is achieved by focusing hard x-rays with two crossed multilayer Laue lenses and raster-scanning a sample with respect to the nanofocusing optics. Various techniques are used to characterize and verify the achieved focus size and imaging resolution. The multimodal imaging is realized by utilizing simultaneously absorption-, phase-, and fluorescence-contrast mechanisms. The combination of high spatial resolution and multimodal imaging enables a comprehensive study of a sample on a very fine length scale. In this work, the unique multimodal imaging capability was used to investigate a mixed ionic-electronic conducting ceramic-based membrane material employed in solid oxide fuel cells and membrane separations (compound of Ce0.8Gd0.2O2‑x and CoFe2O4) which revealed the existence of an emergent material phase and quantified the chemical complexity at the nanoscale.

M6 membrane protein plays an essential role in Drosophila oogenesis.

PubMed

Zappia, María Paula; Brocco, Marcela Adriana; Billi, Silvia C; Frasch, Alberto C; Ceriani, María Fernanda

2011-01-01

We had previously shown that the transmembrane glycoprotein M6a, a member of the proteolipid protein (PLP) family, regulates neurite/filopodium outgrowth, hence, M6a might be involved in neuronal remodeling and differentiation. In this work we focused on M6, the only PLP family member present in Drosophila, and ortholog to M6a. Unexpectedly, we found that decreased expression of M6 leads to female sterility. M6 is expressed in the membrane of the follicular epithelium in ovarioles throughout oogenesis. Phenotypes triggered by M6 downregulation in hypomorphic mutants included egg collapse and egg permeability, thus suggesting M6 involvement in eggshell biosynthesis. In addition, RNAi-mediated M6 knockdown targeted specifically to follicle cells induced an arrest of egg chamber development, revealing that M6 is essential in oogenesis. Interestingly, M6-associated phenotypes evidenced abnormal changes of the follicle cell shape and disrupted follicular epithelium in mid- and late-stage egg chambers. Therefore, we propose that M6 plays a role in follicular epithelium maintenance involving membrane cell remodeling during oogenesis in Drosophila.

M6 Membrane Protein Plays an Essential Role in Drosophila Oogenesis

PubMed Central

Zappia, María Paula; Brocco, Marcela Adriana; Billi, Silvia C.; Frasch, Alberto C.; Ceriani, María Fernanda

2011-01-01

We had previously shown that the transmembrane glycoprotein M6a, a member of the proteolipid protein (PLP) family, regulates neurite/filopodium outgrowth, hence, M6a might be involved in neuronal remodeling and differentiation. In this work we focused on M6, the only PLP family member present in Drosophila, and ortholog to M6a. Unexpectedly, we found that decreased expression of M6 leads to female sterility. M6 is expressed in the membrane of the follicular epithelium in ovarioles throughout oogenesis. Phenotypes triggered by M6 downregulation in hypomorphic mutants included egg collapse and egg permeability, thus suggesting M6 involvement in eggshell biosynthesis. In addition, RNAi-mediated M6 knockdown targeted specifically to follicle cells induced an arrest of egg chamber development, revealing that M6 is essential in oogenesis. Interestingly, M6-associated phenotypes evidenced abnormal changes of the follicle cell shape and disrupted follicular epithelium in mid- and late-stage egg chambers. Therefore, we propose that M6 plays a role in follicular epithelium maintenance involving membrane cell remodeling during oogenesis in Drosophila. PMID:21603606

Introduction to Solid Supported Membrane Based Electrophysiology

PubMed Central

Bazzone, Andre; Costa, Wagner Steuer; Braner, Markus; Călinescu, Octavian; Hatahet, Lina; Fendler, Klaus

2013-01-01

The electrophysiological method we present is based on a solid supported membrane (SSM) composed of an octadecanethiol layer chemisorbed on a gold coated sensor chip and a phosphatidylcholine monolayer on top. This assembly is mounted into a cuvette system containing the reference electrode, a chlorinated silver wire. After adsorption of membrane fragments or proteoliposomes containing the membrane protein of interest, a fast solution exchange is used to induce the transport activity of the membrane protein. In the single solution exchange protocol two solutions, one non-activating and one activating solution, are needed. The flow is controlled by pressurized air and a valve and tubing system within a faraday cage. The kinetics of the electrogenic transport activity is obtained via capacitive coupling between the SSM and the proteoliposomes or membrane fragments. The method, therefore, yields only transient currents. The peak current represents the stationary transport activity. The time dependent transporter currents can be reconstructed by circuit analysis. This method is especially suited for prokaryotic transporters or eukaryotic transporters from intracellular membranes, which cannot be investigated by patch clamp or voltage clamp methods. PMID:23711952

Introduction to solid supported membrane based electrophysiology.

PubMed

Bazzone, Andre; Costa, Wagner Steuer; Braner, Markus; Călinescu, Octavian; Hatahet, Lina; Fendler, Klaus

2013-05-11

The electrophysiological method we present is based on a solid supported membrane (SSM) composed of an octadecanethiol layer chemisorbed on a gold coated sensor chip and a phosphatidylcholine monolayer on top. This assembly is mounted into a cuvette system containing the reference electrode, a chlorinated silver wire. After adsorption of membrane fragments or proteoliposomes containing the membrane protein of interest, a fast solution exchange is used to induce the transport activity of the membrane protein. In the single solution exchange protocol two solutions, one non-activating and one activating solution, are needed. The flow is controlled by pressurized air and a valve and tubing system within a faraday cage. The kinetics of the electrogenic transport activity is obtained via capacitive coupling between the SSM and the proteoliposomes or membrane fragments. The method, therefore, yields only transient currents. The peak current represents the stationary transport activity. The time dependent transporter currents can be reconstructed by circuit analysis. This method is especially suited for prokaryotic transporters or eukaryotic transporters from intracellular membranes, which cannot be investigated by patch clamp or voltage clamp methods.

Inorganic-based proton conductive composite membranes for elevated temperature and reduced relative humidity PEM fuel cells

NASA Astrophysics Data System (ADS)

Wang, Chunmei

Proton exchange membrane (PEM) fuel cells are regarded as highly promising energy conversion systems for future transportation and stationary power generation and have been under intensive investigations for the last decade. Unfortunately, cutting edge PEM fuel cell design and components still do not allow economically commercial implementation of this technology. The main obstacles are high cost of proton conductive membranes, low-proton conductivity at low relative humidity (RH), and dehydration and degradation of polymer membranes at high temperatures. The objective of this study was to develop a systematic approach to design a high proton conductive composite membrane that can provide a conductivity of approximately 100 mS cm-1 under hot and dry conditions (120°C and 50% RH). The approach was based on fundamental and experimental studies of the proton conductivity of inorganic additives and composite membranes. We synthesized and investigated a variety of organic-inorganic Nafion-based composite membranes. In particular, we analyzed their fundamental properties, which included thermal stability, morphology, the interaction between inorganic network and Nafion clusters, and the effect of inorganic phase on the membrane conductivity. A wide range of inorganic materials was studied in advance in order to select the proton conductive inorganic additives for composite membranes. We developed a conductivity measurement method, with which the proton conductivity characteristics of solid acid materials, zirconium phosphates, sulfated zirconia (S-ZrO2), phosphosilicate gels, and Santa Barbara Amorphous silica (SBA-15) were discussed in detail. Composite membranes containing Nafion and different amounts of functionalized inorganic additives (sulfated inorganics such as S-ZrO2, SBA-15, Mobil Composition of Matter MCM-41, and S-SiO2, and phosphonated inorganic P-SiO2) were synthesized with different methods. We incorporated inorganic particles within Nafion clusters either by mixing inorganic gels or solutions with Nafion solution followed by membrane casting or by blending inorganic powders with Nafion solution. The membrane properties, such as acidity, swelling, water uptake, thermostability, proton conductivity, and electrochemical performance, were explored in depth. We characterized the inorganic phase inside composite membranes and its interaction with the Nafion matrix by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Furthermore, we discussed the effect of these inorganic conductors' properties, such as particle size, conductivity, and interaction between functional groups and the Nafion, on the membrane conductivity. The contribution of hydrophilic inorganic particles in improving the membrane fuel cell performance was numerically analyzed by Tafel plot. Finally, the proton conductivity phenomena in composite membranes were simulated with two proton-transport models; one was based on the rule of mixtures, and the other was described by generalized Stefan-Maxwell equations. In the simulation, we proposed a new route in rational design of high proton-conductive composite membranes.

Effect of varying solid membrane area of bristled wings on clap and fling aerodynamics in the smallest flying insects

NASA Astrophysics Data System (ADS)

Ford, Mitchell; Kasoju, Vishwa; Santhanakrishnan, Arvind

2017-11-01

The smallest flying insects with body lengths under 1.5 mm, such as thrips, fairyflies, and some parasitoid wasps, show marked morphological preference for wings consisting of a thin solid membrane fringed with long bristles. In particular, thrips have been observed to use clap and fling wing kinematics at chord-based Reynolds numbers of approximately 10. More than 6,000 species of thrips have been documented, among which there is notable morphological diversity in bristled wing design. This study examines the effect of varying the ratio of solid membrane area to total wing area (including bristles) on aerodynamic forces and flow structures generated during clap and fling. Forewing image analysis on 30 species of thrips showed that membrane area ranged from 16%-71% of total wing area. Physical models of bristled wing pairs with ratios of solid membrane area to total wing area ranging from 15%-100% were tested in a dynamically scaled robotic platform mimicking clap and fling kinematics. Decreasing membrane area relative to total wing area resulted in significant decrease in maximum drag coefficient and comparatively smaller reduction in maximum lift coefficient, resulting in higher peak lift to drag ratio. Flow structures visualized using PIV will be presented.

Solid state oxygen anion and electron mediating membrane and catalytic membrane reactors containing them

DOEpatents

Schwartz, Michael; White, James H.; Sammells, Anthony F.

2005-09-27

This invention relates to gas-impermeable, solid state materials fabricated into membranes for use in catalytic membrane reactors. This invention particularly relates to solid state oxygen anion- and electron-mediating membranes for use in catalytic membrane reactors for promoting partial or full oxidation of different chemical species, for decomposition of oxygen-containing species, and for separation of oxygen from other gases. Solid state materials for use in the membranes of this invention include mixed metal oxide compounds having the brownmillerite crystal structure.

Solid state oxygen anion and electron mediating membrane and catalytic membrane reactors containing them

DOEpatents

Schwartz, Michael; White, James H.; Sammels, Anthony F.

2000-01-01

This invention relates to gas-impermeable, solid state materials fabricated into membranes for use in catalytic membrane reactors. This invention particularly relates to solid state oxygen anion- and electron-mediating membranes for use in catalytic membrane reactors for promoting partial or full oxidation of different chemical species, for decomposition of oxygen-containing species, and for separation of oxygen from other gases. Solid state materials for use in the membranes of this invention include mixed metal oxide compounds having the brownmillerite crystal structure.

First principles study on structural, lattice dynamical and thermal properties of BaCeO3

NASA Astrophysics Data System (ADS)

Zhang, Qingping; Ding, Jinwen; He, Min

2017-09-01

BaCeO3 exhibits impressive application potentials on solid oxide fuel cell electrolyte, hydrogen separation membrane and photocatalyst, owing to its unique ionic and electronic properties. In this article, the electronic structures, phonon spectra and thermal properties of BaCeO3 in orthorhombic, rhombohedral and cubic phases are investigated based on density functional theory. Comparisons with reported experimental results are also presented. The calculation shows that orthorhombic structure is both energetically and dynamically stable under ground state, which is supported by the experiment. Moreover, charge transfer between cations and anions accompanied with phase transition is observed, which is responsible for the softened phonon modes in rhombohedral and cubic phases. Besides, thermal properties are discussed. Oxygen atoms contribute most to the specific heat. The calculated entropy and specific heat at constant pressure fit well with the experimental ones within the measured temperature range.

Cutin and suberin monomers are membrane perturbants.

PubMed

Douliez, Jean-Paul

2004-03-15

The interaction between cutin and suberin monomers, i.e., omega -hydroxylpalmitic acid, alpha, omega -hexadecanedioic acid, alpha, omega --hexadecanediol, 12-hydroxylstearic acid, and phospholipid vesicles biomimicking the lipid structure of plant cell membranes has been studied by optical and transmission electron microscopy, quasielastic light scattering, differential scanning calorimetry, and (31)P solid-state NMR. Monomers were shown to penetrate model membranes until a molar ratio of 30%, modulating their gel to fluid-phase transition, after which monomer crystals also formed in solution. These monomers induced a decrease of the phospholipid vesicle size from several micrometers to about 300 nm. The biological implications of these findings are discussed.

Synthesis of three-dimensional calcium carbonate nanofibrous structure from eggshell using femtosecond laser ablation

PubMed Central

2011-01-01

Background Natural biomaterials from bone-like minerals derived from avian eggshells have been considered as promising bone substitutes owing to their biodegradability, abundance, and lower price in comparison with synthetic biomaterials. However, cell adhesion to bulk biomaterials is poor and surface modifications are required to improve biomaterial-cell interaction. Three-dimensional (3D) nanostructures are preferred to act as growth support platforms for bone and stem cells. Although there have been several studies on generating nanoparticles from eggshells, no research has been reported on synthesizing 3D nanofibrous structures. Results In this study, we propose a novel technique to synthesize 3D calcium carbonate interwoven nanofibrous platforms from eggshells using high repetition femtosecond laser irradiation. The eggshell waste is value engineered to calcium carbonate nanofibrous layer in a single step under ambient conditions. Our striking results demonstrate that by controlling the laser pulse repetition, nanostructures with different nanofiber density can be achieved. This approach presents an important step towards synthesizing 3D interwoven nanofibrous platforms from natural biomaterials. Conclusion The synthesized 3D nanofibrous structures can promote biomaterial interfacial properties to improve cell-platform surface interaction and develop new functional biomaterials for a variety of biomedical applications. PMID:21251288

Electrochemical ion transfer across liquid/liquid interfaces confined within solid-state micropore arrays--simulations and experiments.

PubMed

Strutwolf, Jörg; Scanlon, Micheál D; Arrigan, Damien W M

2009-01-01

Miniaturised liquid/liquid interfaces provide benefits for bioanalytical detection with electrochemical methods. In this work, microporous silicon membranes which can be used for interface miniaturisation were characterized by simulations and experiments. The microporous membranes possessed hexagonal arrays of pores with radii between 10 and 25 microm, a pore depth of 100 microm and pore centre-to-centre separations between 99 and 986 microm. Cyclic voltammetry was used to monitor ion transfer across arrays of micro-interfaces between two immiscible electrolyte solutions (microITIES) formed at these membranes, with the organic phase present as an organogel. The results were compared to computational simulations taking into account mass transport by diffusion and encompassing diffusion to recessed interfaces and overlapped diffusion zones. The simulation and experimental data were both consistent with the situation where the location of the liquid/liquid (l/l) interface was on the aqueous side of the silicon membrane and the pores were filled with the organic phase. While the current for the forward potential scan (transfer of the ion from the aqueous phase to the organic phase) was strongly dependent on the location of the l/l interface, the current peak during the reverse scan (transfer of the ion from the organic phase to the aqueous phase) was influenced by the ratio of the transferring ion's diffusion coefficients in both phases. The diffusion coefficient of the transferring ion in the gelified organic phase was ca. nine times smaller than in the aqueous phase. Asymmetric cyclic voltammogram shapes were caused by the combined effect of non-symmetrical diffusion (spherical and linear) and by the inequality of the diffusion coefficient in both phases. Overlapping diffusion zones were responsible for the observation of current peaks instead of steady-state currents during the forward scan. The characterisation of the diffusion behaviour is an important requirement for application of these silicon membranes in electroanalytical chemistry.

Development Of Antibody-Based Fiber-Optic Sensors

NASA Astrophysics Data System (ADS)

Tromberg, Bruce J.; Sepaniak, Michael J.; Vo-Dinh, Tuan

1988-06-01

The speed and specificity characteristic of immunochemical complex formation has encouraged the development of numerous antibody-based analytical techniques. The scope and versatility of these established methods can be enhanced by combining the principles of conventional immunoassay with laser-based fiber-optic fluorimetry. This merger of spectroscopy and immunochemistry provides the framework for the construction of highly sensitive and selective fiber-optic devices (fluoroimmuno-sensors) capable of in-situ detection of drugs, toxins, and naturally occurring biochemicals. Fluoroimmuno-sensors (FIS) employ an immobilized reagent phase at the sampling terminus of a single quartz optical fiber. Laser excitation of antibody-bound analyte produces a fluorescence signal which is either directly proportional (as in the case of natural fluorophor and "antibody sandwich" assays) or inversely proportional (as in the case of competitive-binding assays) to analyte concentration. Factors which influence analysis time, precision, linearity, and detection limits include the nature (solid or liquid) and amount of the reagent phase, the method of analyte delivery (passive diffusion, convection, etc.), and whether equilibrium or non-equilibrium assays are performed. Data will be presented for optical fibers whose sensing termini utilize: (1) covalently-bound solid antibody reagent phases, and (2) membrane-entrapped liquid antibody reagents. Assays for large-molecular weight proteins (antigens) and small-molecular weight, carcinogenic, polynuclear aromatics (haptens) will be considered. In this manner, the influence of a system's chemical characteristics and measurement requirements on sensor design, and the consequence of various sensor designs on analytical performance will be illustrated.

Astragalin from Cassia alata Induces DNA Adducts in Vitro and Repairable DNA Damage in the Yeast Saccharomyces cerevisiae

PubMed Central

Saito, Samuel; Silva, Givaldo; Santos, Regineide Xavier; Gosmann, Grace; Pungartnik, Cristina; Brendel, Martin

2012-01-01

Reverse phase-solid phase extraction from Cassia alata leaves (CaRP) was used to obtain a refined extract. Higher than wild-type sensitivity to CaRP was exhibited by 16 haploid Saccharomyces cerevisiae mutants with defects in DNA repair and membrane transport. CaRP had a strong DPPH free radical scavenging activity with an IC50 value of 2.27 μg mL−1 and showed no pro-oxidant activity in yeast. CaRP compounds were separated by HPLC and the three major components were shown to bind to DNA in vitro. The major HPLC peak was identified as kampferol-3-O-β-d-glucoside (astragalin), which showed high affinity to DNA as seen by HPLC-UV measurement after using centrifugal ultrafiltration of astragalin-DNA mixtures. Astragalin-DNA interaction was further studied by spectroscopic methods and its interaction with DNA was evaluated using solid-state FTIR. These and computational (in silico) docking studies revealed that astragalin-DNA binding occurs through interaction with G-C base pairs, possibly by intercalation stabilized by H-bond formation. PMID:22489129

Astragalin from Cassia alata induces DNA adducts in vitro and repairable DNA damage in the yeast Saccharomyces cerevisiae.

PubMed

Saito, Samuel; Silva, Givaldo; Santos, Regineide Xavier; Gosmann, Grace; Pungartnik, Cristina; Brendel, Martin

2012-01-01

Reverse phase-solid phase extraction from Cassia alata leaves (CaRP) was used to obtain a refined extract. Higher than wild-type sensitivity to CaRP was exhibited by 16 haploid Saccharomyces cerevisiae mutants with defects in DNA repair and membrane transport. CaRP had a strong DPPH free radical scavenging activity with an IC(50) value of 2.27 μg mL(-1) and showed no pro-oxidant activity in yeast. CaRP compounds were separated by HPLC and the three major components were shown to bind to DNA in vitro. The major HPLC peak was identified as kampferol-3-O-β-d-glucoside (astragalin), which showed high affinity to DNA as seen by HPLC-UV measurement after using centrifugal ultrafiltration of astragalin-DNA mixtures. Astragalin-DNA interaction was further studied by spectroscopic methods and its interaction with DNA was evaluated using solid-state FTIR. These and computational (in silico) docking studies revealed that astragalin-DNA binding occurs through interaction with G-C base pairs, possibly by intercalation stabilized by H-bond formation.

Vaccine to fibroblast growth factor 23 peptides increases eggshell strength.

PubMed

Ren, Z Z; Piepenburg, A J; Bütz, D E; Claus, J R; Cook, M E

2018-03-01

Strategies that would increase eggshell quality could be of considerable value to egg producers. This research demonstrated the effective use of fibroblast growth factor 23 (FGF-23) peptide vaccines to increase eggshell quality of Single Comb White Leghorn laying hens (from 69 to 72 wk of age). Hens, fed a standard diet (containing 900 IU/kg vitamin D3), were intramuscularly injected (and boosted) with either a control vaccine (n = 14 hens) or one of 2 FGF-23 peptide vaccines (peptides NP1, GMNPPPYS; and NP7, YTSTERNSFH; n = 15 hens for each peptide). During peak antibody titer, eggs were collected for shell and internal quality analysis, hens were artificially inseminated, and the hatchability of fertilized eggs was determined. Laying hens vaccinated with either FGF-23 peptide NP1 or NP7 had increased (P < 0.05) plasma phosphate level (mmol/L; NP1 = 1.74, NP7 = 1.76, control = 1.47), egg specific gravity (NP1 = 1.083, NP7 = 1.083, control = 1.079), and eggshell strength (g of force; NP1 = 4002, NP7 = 4157, control = 3102) when compared to control vaccinated hens. FGF-23 peptide NP1 vaccinated hens also had increased eggshell thickness (mm, P < 0.001), shell weight (g, P = 0.032), and shell index (% of whole egg, P = 0.023) when compared to control vaccinated hens. FGF-23 peptide NP7 vaccinated hens tended to have decreased eggshell weight (P = 0.064) when compared to control vaccinated hens. Hatchability of fertilized eggs was not affected in incubations 1 and 3, but tended to be decreased (P = 0.097) by FGF-23 peptide NP1 vaccination in incubation 2. In conclusion, vaccines to FGF-23 peptides increased eggshell quality of laying hens with minimal adverse effects on egg internal quality. The effect of FGF-23 peptide vaccination on hatchability remains to be clarified.

Evaluation of two pilot scale membrane bioreactors for the elimination of selected surfactants from municipal wastewaters

NASA Astrophysics Data System (ADS)

González, Susana; Petrovic, Mira; Barceló, Damiá

2008-07-01

SummaryThe removal of selected surfactants, linear alkylbenzene sulfonates (LAS), coconut diethanol amides (CDEA) and alkylphenol ethoxylates and their degradation products were investigated using a two membrane bioreactor (MBR) with hollow fiber and plate and frame membranes. The two pilot plants MBR run in parallel to a full-scale conventional activated sludge (CAS) treatment. A total of eight influent samples with the corresponding effluent samples were analysed by solid phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS-MS). The results indicate that both MBR have a better effluent quality in terms of chemical and biological oxygen demand (COD and BOD), NH4+ , concentration and total suspended solids (TSS). MBR showed a better similar performance in the overall elimination of the total nonylphenolic compounds, achieving a 75% of elimination or a 65% (the same elimination reached by CAS). LAS and CDEA showed similar elimination in the three systems investigated and no significant differences were observed.

A gravity independent biological grey water treatment system for space applications

NASA Astrophysics Data System (ADS)

Nashashibi, Majda'midhat

2002-09-01

Biological treatment of grey water in space presents serious challenges, stemming mainly from microgravity conditions. The major concerns are phase separation and mass transfer limitations. To overcome solid-liquid phase separation, novel immobilized cell packed bed (ICPB) bioreactors have been developed to treat synthetic grey water. Packed bed bioreactors provide a unique environment for attached microbial growth resulting in high biomass concentrations, which greatly enhance process efficiency with substantial reductions in treatment time and reactor volume. To overcome the gas-liquid phase separation and mass transfer limitations, an oxygenation module equipped with tubular membranes has been developed to deliver bubble-less oxygen under pressure. The selected silicone membranes are hydrophobic, non-porous and oxygen selective. Oxygen dissolves in the walls of the membranes and then diffuses into the water without forming bubbles. Elevated pressures maintain all gaseous by-products in solution and provide high dissolved oxygen concentrations within the system. The packing media are lightweight, inexpensive polyethylene terephthalate (PET) flakes that have large specific surface area, act as a filter for solids and yield highly tortuous flow paths thereby increasing the contact time between the biomass and contaminants. Tests on both pressurized and ambient pressure ICPB bioreactors revealed organic carbon removal efficiencies over 90%. Despite the high ammonia level in the influent, nitrification occured in both the ambient pressure and pressurized nitrification bioreactors at efficiencies of 80% and 60%, respectively. Biomass yield was approximately 0.20 g volatile suspended solids per gram of grey water-COD processed in the pressurized bioreactor. The biomass yield of such novel aerobic ICPB systems is comparable to that of anaerobic processes. These efficient systems produce minimal amounts of biomass compared to other aerobic processes, making them less prone to clogging under long operation periods. The effluent contains low concentration of suspended solids, thus further phase separation may not be necessary. The maintenance requirements are minimal, thereby reducing labor time. The bioreactors could sustain loading and pressure shocks with rapid recovery. An empirical model has been developed for design and scale-up of the pressurized bioreactor for organic carbon and nitrogen conversions. NASA-Johnson Space Center adopted the nitrification bioreactor for prototype testing and potential future use in long duration human space missions.

Use of free water by nesting lesser prairie-chickens

USGS Publications Warehouse

Robinson, Samantha G.; Haukos, David A.; Sullins, Daniel S.; Plumb, Reid T.

2016-01-01

The lesser prairie-chicken (Tympanuchus pallidicinctus) is a grassland grouse of semiarid regions. Use of free water has been hypothesized as necessary for egg formation during drought. We assessed the use of hydrogen isotopes (deuterium, δ2H) to determine if female lesser prairie-chickens use and incorporate free water during egg formation by testing the relationship between isotope ratios in available free water and eggshells. We collected eggshells from 124 nests and 282 free water samples from three sites in Kansas in 2013 and 2014. Eggshells had δ2H values similar to free water in the year of severe drought but were dissimilar the year with lessened drought severity. With an established link between lesser prairie-chicken eggshells and free water during severe drought, we have identified a mechanism behind observations of lesser prairie-chicken water use. We have demonstrated that hydrogen isotopes can be used to test research questions related to use of free water.

Nanoscopic dynamics of phospholipid in unilamellar vesicles: Effect of gel to fluid phase transition

DOE PAGES

Sharma, V. K.; Mamontov, E.; Anunciado, D. B.; ...

2015-03-04

Dynamics of phospholipids in unilamellar vesicles (ULV) is of interest in biology, medical, and food sciences since these molecules are widely used as biocompatible agents and a mimic of cell membrane systems. We have investigated the nanoscopic dynamics of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) phospholipid in ULV as a function of temperature using elastic and quasielastic neutron scattering (QENS). The dependence of the signal on the scattering momentum transfer, which is a critical advantage of neutron scattering techniques, allows the detailed analysis of the lipid motions that cannot be carried out by other means. In agreement with a differential scanning calorimetry measurement, amore » sharp rise in the elastic scattering intensity below ca. 296 K indicates a phase transition from the high-temperature fluid phase to the low-temperature solid gel phase. The microscopic lipid dynamics exhibits qualitative differences between the solid gel phase (in a measurement at 280 K) and the fluid phase (in a measurement at a physiological temperature of 310 K). The data analysis invariably shows the presence of two distinct motions: the whole lipid molecule motion within a monolayer, or lateral diffusion, and the relatively faster internal motion of the DMPC molecule. The lateral diffusion of the whole lipid molecule is found to be Fickian in character, whereas the internal lipid motions are of localized character, consistent with the structure of the vesicles. The lateral motion slows down by an order of magnitude in the solid gel phase, whereas for the internal motion not only the time scale, but also the character of the motion changes upon the phase transition. In the solid gel phase, the lipids are more ordered and undergo uniaxial rotational motion. However, in the fluid phase, the hydrogen atoms of the lipid tails undergo confined translation diffusion rather than uniaxial rotational diffusion. The localized translational diffusion of the hydrogen atoms of the lipid tails is a manifestation of the flexibility of the chains acquired in the fluid phase. Because of this flexibility, both the local diffusivity and the confinement volume for the hydrogen atoms increase linearly from near the lipid s polar head group to the end of its hydrophobic tail. Our results present a quantitative and detailed picture of the effect of the gel-fluid phase transition on the nanoscopic lipid dynamics in ULV. Lastly, the data analysis approach developed here has a potential for probing the dynamic response of lipids to the presence of additional cell membrane components.« less

Membrane-Based Technologies in the Pharmaceutical Industry and Continuous Production of Polymer-Coated Crystals/Particles.

PubMed

Chen, Dengyue; Sirkar, Kamalesh K; Jin, Chi; Singh, Dhananjay; Pfeffer, Robert

2017-01-01

Membrane technologies are of increasing importance in a variety of separation and purification applications involving liquid phases and gaseous mixtures. Although the most widely used applications at this time are in water treatment including desalination, there are many applications in chemical, food, healthcare, paper and petrochemical industries. This brief review is concerned with existing and emerging applications of various membrane technologies in the pharmaceutical and biopharmaceutical industry. The goal of this review article is to identify important membrane processes and techniques which are being used or proposed to be used in the pharmaceutical and biopharmaceutical operations. How novel membrane processes can be useful for delivery of crystalline/particulate drugs is also of interest. Membrane separation technologies are extensively used in downstream processes for bio-pharmaceutical separation and purification operations via microfiltration, ultrafiltration and diafiltration. Also the new technique of membrane chromatography allows efficient purification of monoclonal antibodies. Membrane filtration techniques of reverse osmosis and nanofiltration are being combined with bioreactors and advanced oxidation processes to treat wastewaters from pharmaceutical plants. Nanofiltration with organic solvent-stable membranes can implement solvent exchange and catalyst recovery during organic solvent-based drug synthesis of pharmaceutical compounds/intermediates. Membranes in the form of hollow fibers can be conveniently used to implement crystallization of pharmaceutical compounds. The novel crystallization methods of solid hollow fiber cooling crystallizer (SHFCC) and porous hollow fiber anti-solvent crystallization (PHFAC) are being developed to provide efficient methods for continuous production of polymer-coated drug crystals in the area of drug delivery. This brief review provides a general introduction to various applications of membrane technologies in the pharmaceutical/biopharmaceutical industry with special emphasis on novel membrane techniques for pharmaceutical applications. The method of coating a drug particle with a polymer using the SHFCC method is stable and ready for scale-up for operation over an extended period. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Enhanced adsorption of Ca-ATPase containing vesicles on a negatively charged solid-supported-membrane for the investigation of membrane transporters.

PubMed

Sacconi, Alessio; Moncelli, Maria Rosa; Margheri, Giancarlo; Tadini-Buoninsegni, Francesco

2013-11-12

A convenient model system for a biological membrane is a solid-supported membrane (SSM), which consists of a gold-supported alkanethiol|phospholipid bilayer. In combination with a concentration jump method, SSMs have been used for the investigation of several membrane transporters. Vesicles incorporating sarcoplasmic reticulum Ca-ATPase (SERCA) were adsorbed on a negatively charged SSM (octadecanethiol|phosphatidylserine bilayer). The current signal generated by the adsorbed vesicles following an ATP concentration jump was compared to that produced by SERCA-containing vesicles adsorbed on a conventional SSM (octadecanethiol|phosphatidylcholine bilayer). A significantly higher current amplitude was recorded on the serine-based SSM. The adsorption of SERCA-incorporating vesicles on the SSM was then characterized by surface plasmon resonance (SPR). The SPR measurements clearly indicate that in the presence of Ca(2+) and Mg(2+), the amount of adsorbed vesicles on the serine-based SSM is about twice that obtained using the conventional SSM, thereby demonstrating that the higher current amplitude recorded on the negatively charged SSM is correlated with a greater quantity of adsorbed vesicles. The enhanced adsorption of membrane vesicles on the PS-based SSM may be useful to study membrane preparations with a low concentration of transport protein generating small current signals, as in the case of various recombinantly expressed proteins.

Measuring the equation of state for a 2D colloidal membrane: A microfluidic approach to buffer exchange

NASA Astrophysics Data System (ADS)

Balchunas, Andrew; Cabanas, Rafael; Fraden, Seth; Dogic, Zvonimir

Previous work has shown that monodisperse rod-like colloidal particles, such as a filamentous bacteriophage, self assemble into a 2D monolayer smectic in the presence of a non-adsorbing depleting polymer. These structures have the same functional form of bending rigidity and lateral compressibility as conventional lipid bi-layers, so we name the monolayer smectic a colloidal membrane. We have developed a microfluidic device such that the osmotic pressure acting on a colloidal membrane may be controlled via a full in situ buffer exchange. Rod density within individual colloidal membranes was measured as a function of osmotic pressure and a first order phase transition, from 2D fluid to 2D solid, was observed. kon and koff rates of rod to membrane binding were measured by lowering the osmotic pressure until membrane evaporation occurred.

Microalgae fractionation using steam explosion, dynamic and tangential cross-flow membrane filtration.

PubMed

Lorente, E; Hapońska, M; Clavero, E; Torras, C; Salvadó, J

2017-08-01

In this study, the microalga Nannochloropsis gaditana was subjected to acid catalysed steam explosion treatment and the resulting exploded material was subsequently fractionated to separate the different fractions (lipids, sugars and solids). Conventional and vibrational membrane setups were used with several polymeric commercial membranes. Two different routes were followed: 1) filtration+lipid solvent extraction and 2) lipid solvent extraction+filtration. Route 1 revealed to be much better since the used membrane for filtration was able to permeate the sugar aqueous phase and retained the fraction containing lipids; after this, an extraction required a much lower amount of solvent and a better recovering yield. Filtration allowed complete lipid rejection. Dynamic filtration improved permeability compared to the tangential cross-flow filtration. Best membrane performance was achieved using a 5000Da membrane with the dynamic system, obtaining a permeability of 6L/h/m 2 /bar. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influence of Inner Transducer Properties on EMF Response and Stability of Solid-Contact Anion Selective Membrane Electrodes Based on Metalloporphyrin Ionophores

PubMed Central

Górski, Łukasz; Matusevich, Alexey; Pietrzak, Mariusz; Wang, Lin; Meyerhoff, Mark E.; Malinowska, Elżbieta

2010-01-01

The performance of solid-contact/coated wire type electrodes with plasticized PVC membranes containing metalloporphyrins as anion selective ionophores is reported. The membranes are deposited on transducers based on graphite pastes and graphite rods. The hydrophobicity of the underlying conductive transducer surface is found to be a key factor that influences the formation of an aqueous layer beneath the polymer film. Elimination of this ill-defined water layer greatly improves the electrochemical properties of the ion-sensors, such as EMF stability and life-time. Only highly lipophilic electrode substrates, namely graphite paste with mineral oil, were shown to prevent the formation of aqueous layer underneath the ion-sensing membrane. The possibility of employing Co(III)-tetraphenylporphyrin both as NO2− selective ionophore and as electron/ion conducting species to ensure ion-to-electron translation was also discussed based on the results of preliminary experiments. PMID:20357903

Timing of the calcium intake and effect of calcium deficiency on behaviour and egg laying in captive great tits, Parus major.

PubMed

Graveland, J; Berends, A E

1997-01-01

The calcium demand of egg-laying birds is much higher than in other vertebrates during reproduction. We showed elsewhere that a low level of calcium availability can greatly affect the eggshell quality and reproduction of free-living passerines. However, there are few data on calcium demand and calcium intake in relation to egg laying and behaviour and egg-laying performance under conditions of calcium shortage in nondomesticated birds. We examined these aspects in an experiment with captive great tits, Parus major, on a diet deficient in calcium, with or without snail shells as an additional calcium source. More than 90% of the calcium intake for egg production took place during the egg-laying period. Females ingested about 1.7 times as much calcium as they deposited in eggshells. Removing the snail shells after the first egg resulted in eggshell defects and interruptions of laying after 1-3 d. Females without snail shells doubled their searching effort and started to burrow in the soil and to eat sand, small stones, and their own eggs. Most calcium was consumed in the evening, probably to supplement the calcium available from the medullary bone with an additional calcium source in the gut during eggshell formation. The results demonstrated that eggshell formation requires accurate timing of the calcium intake and that obtaining sufficient calcium is time-consuming, even in calcium-rich environments. These factors pertaining to calcium intake greatly affect the ability of birds to collect sufficient calcium for eggshell formation in calcium-poor areas.

Nesting environment may drive variation in eggshell structure and egg characteristics in the Testudinata.

PubMed

Deeming, D Charles

2018-05-14

Testudines exhibit considerable variation in the degree of eggshell calcification, which affects eggshell conductance, water physiology of the embryos, and calcium metabolism of embryos. However, the underlying reason for different shell types has not been explored. Phylogenetically controlled analyses examined relationships between egg size, shell mass, and clutch size in ∼200 turtle species from a range of body sizes and assigned by family as laying either rigid- or pliable-shelled eggs. Shell type affected egg breadth relative to pelvic dimensions, egg mass, and relative shell mass but did not affect size, mass, or total shell mass of the clutch. These results suggest that calcium availability may be a function of body size and the type of shell may reflect in part the interplay between clutch size and egg size. It was further concluded that the eggshell probably evolved as a means of physical protection. Differences in shell calcification may not primarily reflect reproductive parameters but rather correlate with the acidity of a species' nesting environment. Low pH environments may have thicker calcareous layer to counteract the erosion caused by the soil and maintain the integrity of the physical barrier. Limited calcium availability may constrain clutch size. More neutral nesting substrates expose eggshells to less erosion so calcification per egg can be reduced and this allows larger clutch sizes. This pattern is also reflected in thick, calcified crocodilian eggs. Further research is needed to test whether eggshell calcification in the testudines correlates with nest pH in order to verify this relationship. © 2018 Wiley Periodicals, Inc.

Use of Membrane Filtration as an Alternative Method in the Extraction of Microcystins Produced by Harmful Algal Blooms

EPA Science Inventory

Current methods invariably require sample concentration, typically solid-phase extraction, so as to be amendable for measurement at ambient concentration levels. Such methods (i.e. EPA Method 544) are only validated for a limited number of the known variants where standards are ...

Preparation of curcumin self-micelle solid dispersion with enhanced bioavailability and cytotoxic activity by mechanochemistry.

PubMed

Zhang, Qihong; Polyakov, Nikolay E; Chistyachenko, Yulia S; Khvostov, Mikhail V; Frolova, Tatjana S; Tolstikova, Tatjana G; Dushkin, Alexandr V; Su, Weike

2018-11-01

An amorphous solid dispersion (SD) of curcumin (Cur) with disodium glycyrrhizin (Na 2 GA) was prepared by mechanical ball milling. Curcumin loaded micelles were self-formed by Na 2 GA when SD dissolved in water. The physical properties of Cur SD in solid state were characterized by differential scanning calorimetry, X-ray diffraction studies, and scanning electron microscope. The characteristics of the sample solutions were analyzed by reverse phase HPLC, UV-visible spectroscopy, 1 H NMR spectroscopy, gel permeation LC, and transmission electron microscopy. In vitro cytotoxic tests demonstrated that Cur SD induced higher cytotoxicity against glioblastoma U-87 MG cells than free Cur. Besides, an improvement of membrane permeability of Cur SD was confirmed by parallel artificial membrane permeability assay. Further pharmacokinetic study of this SD formulation in rat showed a significant ∼19-fold increase of bioavailability as comparing to free Cur. Thus, Cur SD provide a more potent and efficacious formulation for Cur oral delivery.

A solid phase enzyme-linked immunosorbent assay for the antigenic detection of Legionella pneumophila (serogroup 1): A compliment for the space station diagnostic capability

NASA Technical Reports Server (NTRS)

Hejtmancik, Kelly E.

1987-01-01

It is necessary that an adequate microbiology capability be provided as part of the Health Maintenance Facility (HMF) to support expected microbial disease events and environmental monitoring during long periods of space flight. The application of morphological and biochemical studies to confirm the presence of certain bacterial and fungal disease agents are currently available and under consideration. This confirmation would be facilitated through employment of serological methods to aid in the identification of bacterial, fungal, and viral agents. A number of serological approaches are currently being considered, including the use of Enzyme Linked Immunosorbent Assay (ELISA) technology, which could be utilized during microgravity conditions. A solid phase, membrane supported ELISA for the detection of Legionella pneumophila, an expected disease agent, was developed to show a potential model system that would meet the HMF requirements and specifications for the future space station. These studies demonstrate the capability of membrane supported ELISA systems for identification of expected microbial disease agents as part of the HMF.

Effects of TiO2 and ZrO2 nanofillers in LiBOB based PVdF/PVC composite polymer electrolytes (CPE)

NASA Astrophysics Data System (ADS)

Aravindan, V.; Vickraman, P.

2007-11-01

A novel type of lithium bis(oxalato)borate (LiBOB) synthesized by the solid-state reaction method has been presented. LiBOB composite polymer electrolytes (CPE) prepared with dispersions of TIO2/ZrO2with various concentrations into the host blend matrices of poly(vinylidenefluoride) (PVdF)-poly(vinylchloride) (PVC) are investigated by scanning electron microscopy, x-ray diffraction (XRD) and ac impedance measurements. The plasticizing agent selected for the present study is a mixture of ethylene carbonate (EC) and diethyl carbonate (DEC) for the phase separated morphology of the studied polymers. The impedance studies on CPE membranes identify that membranes, with 2.5 wt% of fillers, have enhanced conductivities of 5.43 × 10-4 S cm-1 and 4.38 × 10-4 S cm-1, respectively, for TiO2 and ZrO2 at ambient temperature. The XRD investigations confirm that the membranes with filler levels exceeding the limit of 2.5 wt% show a gradual increase in the degree of crystallinity, rendering them less conducting. The activation energy calculations also highlight variations in conductivities of all the membranes.

Fluorescent molecular probes based on excited state prototropism in lipid bilayer membrane

NASA Astrophysics Data System (ADS)

Mohapatra, Monalisa; Mishra, Ashok K.

2012-03-01

Excited state prototropism (ESPT) is observed in molecules having one or more ionizable protons, whose proton transfer efficiency is different in ground and excited states. The interaction of various ESPT molecules like naphthols and intramolecular ESPT (ESIPT) molecules like hydroxyflavones etc. with different microheterogeneous media have been studied in detail and excited state prototropism as a probe concept has been gaining ground. The fluorescence of different prototropic forms of such molecules, on partitioning to an organized medium like lipid bilayer membrane, often show sensitive response to the local environment with respect to the local structure, physical properties and dynamics. Our recent work using 1-naphthol as an ESPT fluorescent molecular probe has shown that the incorporation of monomeric bile salt molecules into lipid bilayer membranes composed from dipalmitoylphosphatidylcholine (DPPC, a lung surfactant) and dimyristoylphosphatidylcholine (DMPC), in solid gel and liquid crystalline phases, induce appreciable wetting of the bilayer up to the hydrocarbon core region, even at very low (<= 1 mM) concentrations of the bile salts. The incorporation and location of fisetin, an ESIPT molecule having antioxidant properties, in lipid bilayer membrane has been sensitively monitored from its intrinsic fluorescence behaviour.

Development of electrochemical super capacitors for EMA applications

NASA Technical Reports Server (NTRS)

Kosek, J. A.; Dunning, T.; Laconti, A. B.

1995-01-01

In a NASA SBIR Phase I program (Contract No. NAS8-40119), Giner, Inc. evaluated the feasibility of fabricating an all-solid-ionomer multicell electrochemical capacitor having a unit cell capacitance greater than 2 F/sq cm and a repeating element thickness of 6 mils. This capacitor can possibly be used by NASA as a high-rate energy source for electromechanical actuator (EMA) activation for advanced space missions. The high unit cell capacitance and low repeating element thickness will allow for the fabrication of a low-volume, low-weight device, favorable characteristics for space applications. These same characteristics also make the capacitor attractive for terrestrial applications, such as load-leveling batteries or fuel cells in electric vehicle applications. Although the projected energy densities for electrochemical capacitors are about two orders of magnitude lower than that of batteries, the high-power-density characteristics of these devices render them as potentially viable candidates for meeting pulse or peak electrical power requirements for some anticipated aerospace mission scenarios, especially those with discharge times on the millisecond to second time scale. On a volumetric or gravimetric basis, the advantages of utilizing electrochemical capacitors rather than batteries for meeting the peak power demands associated with a specific mission scenario will largely depend upon the total and pulse durations of the power peaks. The effect of preparation conditions on RuO(x), the active component in an all-solid-ionomer electrochemical capacitor, was evaluated during this program. Methods were identified to prepare RuO(x) having a surface areagreater than 180 sq m/g, and a capacitance of greater than 2 F/sq cm. Further efforts to reproducibly obtain these high-surface-area materials in scaled-up batches will be evaluated in Phase 2. During this Phase 1 program we identified a superior Nafion 105 membrane, having a film thickness of 5 mils, that showed excellent performance in our all-solid-ionomer capacitors and resulted in electrochemical capacitors with a repeating element thickness of 8 mils. We are currently working with membrane manufacturers to obtain a high performance membrane in less than 3 mil thickness to obtain a repeating element thickness of 6 mils or less. A 10-cell all-solid ionomer capacitor stack, with each cell having a 222 sq cm active area, was fabricated and evaluated as part of the Phase 1 program. Further Scale-up of a high-energy-density stack is plannedin Phase 2.

Morphological control of La0.7Sr0.3Co0.2Fe0.8O3-δ and La0.7Sr0.3MnO3-δ catalytic membrane using PEG-H2O additive

NASA Astrophysics Data System (ADS)

Iqbal, R. M.; Nurherdiana, S. D.; Hartanto, D.; Othman, M. H. D.; Fansuri, H.

2018-04-01

Methane is the primary combustible component in non condensable part of natural gas. It is a promising source for syngas (CO and H2) production by partial oxidation method. The conversion of methane to syngas by partial oxidation method needs a controlled amount of oxygen. Membrane which has asymmetric structure and selectively permeates oxygen can be used to supply just enough oxygen to the reaction. One pathway to the fabricate asymmetric membrane is phase inversion method with an addition of PEG to increase pore size. La0.7Sr0.3Co0.2Fe0.8O3-δ (LSCF 7328) and Laa0.7Sr0.3MnO3-δ (LSM 73) powder were synthesized by solid-state method and they were characterized by XRD. The green membrane was prepared by phase inversion method. A dope solution was made by mixing LSCF 7328 or LSM 73 powder with PEG and stirred them in NMP for 24 h. PESf was then added into the dope solution and the stirring was continued to another 24 h. The resulted dope solution was degassed by immersing the solution inside and conical flask in an ultrasonic bath to remove air bubbles. The degassed mixture was then casted by spreading it on a glass surface (with a thickness of 2 mm) followed by immersion in a water bath for 24 h to coagulate the degassed mixture. Membrane morphology was characterized by Scanning Electron Microscopy (SEM) while the decomposition temperature of the polymer binder was analyzed by Thermogravimetric Analyzer (TGA). The XRD results show that phase of LSCF 7328 and LSM 73 are similar to LaCoO3 and LaMnO3, respectively. It indicated that the perovskite synthesis was successful. SEM micrograph of membrane cross sections show that the green membrane have finger like pores and a dense layer. Pores also appear on top and bottom surface of the membrane. Based on TGA results, the highest weight lost of green membrane at 550-600°C which represents the decomposition of PESf binder.

Solid oxide MEMS-based fuel cells

DOEpatents

Jankowksi, Alan F.; Morse, Jeffrey D.

2007-03-13

A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. The electrolyte layer can consist of either a solid oxide or solid polymer material, or proton exchange membrane electrolyte materials may be used. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

Solid polymer MEMS-based fuel cells

DOEpatents

Jankowski, Alan F [Livermore, CA; Morse, Jeffrey D [Pleasant Hill, CA

2008-04-22

A micro-electro-mechanical systems (MEMS) based thin-film fuel cells for electrical power applications. The MEMS-based fuel cell may be of a solid oxide type (SOFC), a solid polymer type (SPFC), or a proton exchange membrane type (PEMFC), and each fuel cell basically consists of an anode and a cathode separated by an electrolyte layer. The electrolyte layer can consist of either a solid oxide or solid polymer material, or proton exchange membrane electrolyte materials may be used. Additionally catalyst layers can also separate the electrodes (cathode and anode) from the electrolyte. Gas manifolds are utilized to transport the fuel and oxidant to each cell and provide a path for exhaust gases. The electrical current generated from each cell is drawn away with an interconnect and support structure integrated with the gas manifold. The fuel cells utilize integrated resistive heaters for efficient heating of the materials. By combining MEMS technology with thin-film deposition technology, thin-film fuel cells having microflow channels and full-integrated circuitry can be produced that will lower the operating temperature an will yield an order of magnitude greater power density than the currently known fuel cells.

Purification of plant plasma membranes by two-phase partitioning and measurement of H+ pumping.

PubMed

Lund, Anette; Fuglsang, Anja Thoe

2012-01-01

Purification of plasma membranes by two-phase partitioning is based on the separation of microsomal membranes, dependent on their surface hydrophobicity. Here we explain the purification of plasma membranes from a relatively small amount of material (7-30 g). The fluorescent probe ACMA (9-amino-6-chloro-2-metoxyacridine) accumulates inside the vesicles upon protonation. Quenching of ACMA in the solution corresponds to the H(+) transport across the plasma membrane. Before running the assay, the plasma membranes are incubated with the detergent Brij-58 in order to create inside-out vesicles.Purification of plasma membranes by two-phase partitioning is based on the separation of microsomal membranes, dependent on their surface hydrophobicity. Here we explain the purification of plasma membranes from a relatively small amount of material (7-30 g). The fluorescent probe ACMA (9-amino-6-chloro-2-metoxyacridine) accumulates inside the vesicles upon protonation. Quenching of ACMA in the solution corresponds to the H(+) transport across the plasma membrane. Before running the assay, the plasma membranes are incubated with the detergent Brij-58 in order to create inside-out vesicles.

Eggshell porosity covaries with egg size among female House Wrens (Troglodytes aedon) but is unrelated to incubation onset and egg-laying order within clutches.

PubMed

Bowers, E K; White, A; Lang, A; Podgorski, L; Thompson, C F; Sakaluk, S K; Jaeckle, W B; Harper, R G

2015-06-01

In birds, the duration of egg incubation (the time from incubation onset to hatching) can affect multiple components of nest success, but what affects incubation duration? Previous studies suggest that incubation duration is affected by both parental behavior and components of the egg, which have yet to be determined. One egg component that may be related to incubation behavior and the time until hatching is eggshell porosity, which affects the exchange of metabolic gasses and water vapor across the shell and, thus, the speed of embryonic development and incubation duration. We tested whether eggshell porosity was associated with the timing of incubation onset by female House Wrens ( Troglodytes aedon Vieillot, 1809), and whether porosity varied within clutches in a manner that might be associated with incubation periods and hatching patterns (i.e., synchronous vs. asynchronous hatching). Eggshell porosity was unrelated to the onset of maternal incubation and did not differ between early and later-laid eggs within clutches, but differed significantly among females and covaried with egg size. We conclude that producing all eggshells of similar porosity within clutches, while adjusting incubation onset once most or all eggs are laid, provide facultative maternal control over variation in hatching patterns.

Immobilization of Pb, Cd, and Zn in a contaminated soil using eggshell and banana stem amendments: metal leachability and a sequential extraction study.

PubMed

Ashrafi, Mehrnaz; Mohamad, Sharifah; Yusoff, Ismail; Shahul Hamid, Fauziah

2015-01-01

Heavy-metal-contaminated soil is one of the major environmental pollution issues all over the world. In this study, two low-cost amendments, inorganic eggshell and organic banana stem, were applied to slightly alkaline soil for the purpose of in situ immobilization of Pb, Cd, and Zn. The artificially metal-contaminated soil was treated with 5% eggshell or 10% banana stem. To simulate the rainfall conditions, a metal leaching experiment for a period of 12 weeks was designed, and the total concentrations of the metals in the leachates were determined every 2 weeks. The results from the metal leaching analysis revealed that eggshell amendment generally reduced the concentrations of Pb, Cd, and Zn in the leachates, whereas banana stem amendment was effective only on the reduction of Cd concentration in the leachates. A sequential extraction analysis was carried out at the end of the experiment to find out the speciation of the heavy metals in the amended soils. Eggshell amendment notably decreased mobility of Pb, Cd, and Zn in the soil by transforming their readily available forms to less accessible fractions. Banana stem amendment also reduced exchangeable form of Cd and increased its residual form in the soil.

Microbiome assembly of avian eggshells and their potential as transgenerational carriers of maternal microbiota.

PubMed

van Veelen, H Pieter J; Salles, Joana Falcão; Tieleman, B Irene

2018-05-01

The microbiome is essential for development, health and homeostasis throughout an animal's life. Yet, the origins and transmission processes governing animal microbiomes remain elusive for non-human vertebrates, oviparous vertebrates in particular. Eggs may function as transgenerational carriers of the maternal microbiome, warranting characterisation of egg microbiome assembly. Here, we investigated maternal and environmental contributions to avian eggshell microbiota in wild passerine birds: woodlark Lullula arborea and skylark Alauda arvensis. Using 16S rRNA gene sequencing, we demonstrated in both lark species, at the population and within-nest levels, that bacterial communities of freshly laid eggs were distinct from the female cloacal microbiome. Instead, soil-borne bacteria appeared to thrive on freshly laid eggs, and eggshell microbiota composition strongly resembled maternal skin, body feather and nest material communities, sources in direct contact with laid eggs. Finally, phylogenetic structure analysis and microbial source tracking underscored species sorting from directly contacting sources rather than in vivo-transferred symbionts. The female-egg-nest system allowed an integrative assessment of avian egg microbiome assembly, revealing mixed modes of symbiont acquisition not previously documented for vertebrate eggs. Our findings illuminated egg microbiome origins, which suggested a limited potential of eggshells for transgenerational transmission, encouraging further investigation of eggshell microbiome functions in vertebrates.

Factors Affecting Element Concentrations in Eggshells of Three Sympatrically Nesting Waterbirds in Northern Poland.

PubMed

Kitowski, Ignacy; Jakubas, Dariusz; Indykiewicz, Piotr; Wiącek, Dariusz

2018-02-01

Avian eggshells are convenient samples in biomonitoring studies, because they are easily accessible, especially from colonially or semicolonially breeding birds. In the present study, concentrations of 17 elements, including heavy metals and essential elements in post-hatch eggshells, were compared among three species of waterbirds of differing strategies for gaining reserves for egg production and diet: mallard, Anas platyrhynchos (ML, a capital breeder, mainly herbivorous), common tern, Sterna hirundo (CT, an income breeder, piscivorous) and black-headed gull, Chroicocephalus ridibundus (BHG, mixed strategy, omnivorous) and breeding sympatrically in three sites in North Poland. Analyses revealed that Fe, Zn, and Cu levels differed the most in the studied species, which may be explained by various contributions of fish, aquatic plants, and soil invertebrates in their diets. Generally, the studied species' eggshells accumulated amounts of elements comparable to those reported for other waterbirds without putting the growth and development of the embryo at risk. The only exception was very high levels of Cr in ML and CT, which may be explained by their foraging on aquatic organisms in waterbodies polluted by this element. Intersite differences in eggshell concentrations of Ni, Sr, Hg and Cr in CT (an income breeder) may be explained by the influence of local pollution sources (small factories, polluted river).

Blue-green eggshell coloration is not a sexually selected signal of female quality in an open-nesting polygynous passerine.

PubMed

Honza, Marcel; Požgayová, Milica; Procházka, Petr; Cherry, Michael I

2011-06-01

It has been proposed that blue-green egg colours have evolved as a post-mating signal of female quality, selected by males allocating their parental effort in response to the strength of this signal. We tested two main assumptions of the sexually selected egg coloration hypothesis: (1) whether the intensity of eggshell blue-green chroma (BGC) reflects female quality; and (2) whether males make their decisions on the level of parental care that they provide according to the intensity of eggshell BGC. As a model species, we chose the facultatively polygynous great reed warbler (Acrocephalus arundinaceus). In this species, females simultaneously paired with the same male, compete for his nest attendance and could benefit from signalling their quality through egg coloration. However, we found no association between the variation in eggshell BGC and the measures of female quality (physical condition, mean egg volume and age). Moreover, great reed warbler males did not adjust their investment (as measured in terms of nest defence against a brood parasite) in relation to the eggshell BGC. We conclude that blue-green egg coloration in this open-nesting passerine is unlikely to have a signalling function. Rather, the large colour variation among clutches of individual females may depend on yearly fluctuations in environmental conditions.

Common Loon (Gavia immer) eggshell thickness and egg volume vary with acidity of nest lake in northern Wisconsin

USGS Publications Warehouse

Pollentier, C.D.; Kenow, K.P.; Meyer, M.W.

2007-01-01

Environmental acidification has been associated with factors that may negatively affect reproduction in many waterbirds. Declines in lake pH can lead to reductions in food availability and quality, or result in the altered availability of toxic metals, such as mercury. A recent laboratory study conducted by the U.S. Geological Survey and the Wisconsin Department of Natural Resources indicated that Common Loon (Gavia immer) chicks hatched from eggs collected on acidic lakes in northern Wisconsin may be less responsive to stimuli and exhibit reduced growth compared to chicks from neutral-pH lakes. Here we report on the relation between Common Loon egg characteristics (eggshell thickness and egg volume) and lake pH, as well as eggshell methylmercury content. Eggs (N = 84) and lake pH measurements were obtained from a four county region of northern Wisconsin. Egg-shells were 3-4% thinner on lakes with pH ??? 6.3 than on neutral-pH lakes and this relation was linear across the pH range investigated (P 0.05, n.s.) or lake pH. Results suggest that low lake pH may be associated with thinner eggshells and reduced egg volume in Common Loons. We speculate on the mechanisms that may lead to this phenomeno.

Enhancements and limits in drug membrane transport using supersaturated solutions of poorly water soluble drugs.

PubMed

Raina, Shweta A; Zhang, Geoff G Z; Alonzo, David E; Wu, Jianwei; Zhu, Donghua; Catron, Nathaniel D; Gao, Yi; Taylor, Lynne S

2014-09-01

Amorphous solid dispersions (ASDs) give rise to supersaturated solutions (solution concentration greater than equilibrium crystalline solubility). We have recently found that supersaturating dosage forms can exhibit the phenomenon of liquid-liquid phase separation (LLPS). Thus, the high supersaturation generated by dissolving ASDs can lead to a two-phase system wherein one phase is an initially nanodimensioned and drug-rich phase and the other is a drug-lean continuous aqueous phase. Herein, the membrane transport of supersaturated solutions, at concentrations above and below the LLPS concentration has been evaluated using a side-by-side diffusion cell. Measurements of solution concentration with time in the receiver cell yield the flux, which reflects the solute thermodynamic activity in the donor cell. As the nominal concentration of solute in the donor cell increases, a linear increase in flux was observed up to the concentration where LLPS occurred. Thereafter, the flux remained essentially constant. Both nifedipine and felodipine solutions exhibit such behavior as long as crystallization is absent. This suggests that there is an upper limit in passive membrane transport that is dictated by the LLPS concentration. These results have several important implications for drug delivery, especially for poorly soluble compounds requiring enabling formulation technologies. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.

Visualization of Membrane Rafts Using a Perylene Monoimide Derivative and Fluorescence Lifetime Imaging

PubMed Central

Margineanu, Anca; Hotta, Jun-ichi; Van der Auweraer, Mark; Ameloot, Marcel; Stefan, Alina; Beljonne, David; Engelborghs, Yves; Herrmann, Andreas; Müllen, Klaus; De Schryver, Frans C.; Hofkens, Johan

2007-01-01

A new membrane probe, based on the perylene imide chromophore, with excellent photophysical properties (high absorption coefficient, quantum yield (QY) ≈ 1, high photostability) and excited in the visible domain is proposed for the study of membrane rafts. Visualization of separation between the liquid-ordered (Lo) and the liquid-disordered (Ld) phases can be achieved in artificial membranes by fluorescence lifetime imaging due to the different decay times of the membrane probe in the two phases. Rafts on micrometer-scale in cell membranes due to cellular activation can also be observed by this method. The decay time of the dye in the Lo phase is higher than in organic solvents where its QY is 1. This allows proposing a (possible general) mechanism for the decay time increase in the Lo phase, based on the local field effects of the surrounding molecules. For other fluorophores with QY < 1, the suggested mechanism could also contribute, in addition to effects reducing the nonradiative decay pathways, to an increase of the fluorescence decay time in the Lo phase. PMID:17573424

31P and 1H NMR Studies of the Molecular Organization of Lipids in the Parallel Artificial Membrane Permeability Assay.

PubMed

Assmus, Frauke; Ross, Alfred; Fischer, Holger; Seelig, Joachim; Seelig, Anna

2017-01-03

The parallel artificial membrane permeability assay (PAMPA) has emerged as a widely used primary in vitro screen for passive permeability of potential drug candidates. However, the molecular structure of the permeation barrier (consisting of a filter-supported dodecane-egg lecithin mixture) has never been characterized. Here, we investigated the long-range order of phospholipids in the PAMPA barrier by means of 31 P static solid-state NMR. Diffusion constants of PAMPA membrane components were derived from liquid state NMR and, in addition, drug distribution between the PAMPA lipid phase and buffer (log D PAMPA at pH 7.4) was systematically investigated. Increasing concentration of n-dodecane to the system egg lecithin-water (lamellar phase, L α ) induces formation of inverted hexagonal (H ii ) and isotropic phases. At n-dodecane concentrations matching those used in PAMPA (9%, w/v) a purely "isotropic" phase was observed corresponding to lipid aggregates with a diameter in the range 4-7 nm. Drug distribution studies indicate that these reverse micelles facilitate the binding to, and in turn the permeation across, the PAMPA dodecane barrier, in particular for amphiphilic solutes. The proposed model for the molecular architecture and function of the PAMPA barrier provides a fundamental, hitherto missing framework to evaluate the scope but also limitations of PAMPA for the prediction of in vivo membrane permeability.

Exploiting the Phenomenon of Liquid-Liquid Phase Separation for Enhanced and Sustained Membrane Transport of a Poorly Water-Soluble Drug.

PubMed

Indulkar, Anura S; Gao, Yi; Raina, Shweta A; Zhang, Geoff G Z; Taylor, Lynne S

2016-06-06

Recent studies on aqueous supersaturated lipophilic drug solutions prepared by methods including antisolvent addition, pH swing, or dissolution of amorphous solid dispersions (ASDs) have demonstrated that when crystallization is slow, these systems undergo liquid-liquid phase separation (LLPS) when the concentration of the drug in the medium exceeds its amorphous solubility. Following LLPS, a metastable equilibrium is formed where the concentration of drug in the continuous phase corresponds to the amorphous solubility while the dispersed phase is composed of a nanosized drug-rich phase. It has been reasoned that the drug-rich phase may act as a reservoir, enabling the rate of passive transport of the drug across a membrane to be maintained at the maximum value for an extended period of time. Herein, using clotrimazole as a model drug, and a flow-through diffusion cell, the reservoir effect is demonstrated. Supersaturated clotrimazole solutions at concentrations below the amorphous solubility show a linear relationship between the maximum flux and the initial concentration. Once the concentration exceeds the amorphous solubility, the maximum flux achieved reaches a plateau. However, the duration for which the high flux persists was found to be highly dependent on the number of drug-rich nanodroplets present in the donor compartment. Macroscopic amorphous particles of clotrimazole did not lead to the same reservoir effect observed with the nanodroplets formed through the process of LLPS. A first-principles mathematical model was developed which was able to fit the experimental receiver concentration-time profiles for concentration regimes both below and above amorphous solubility, providing support for the contention that the nanodroplet phase does not directly diffuse across the membrane but, instead, rapidly replenishes the drug in the aqueous phase that has been removed by transport across the membrane. This study provides important insight into the properties of supersaturated solutions and how these might in turn impact oral absorption through effects on passive membrane transport rates.

Membranes in Lithium Ion Batteries

PubMed Central

Yang, Min; Hou, Junbo

2012-01-01

Lithium ion batteries have proven themselves the main choice of power sources for portable electronics. Besides consumer electronics, lithium ion batteries are also growing in popularity for military, electric vehicle, and aerospace applications. The present review attempts to summarize the knowledge about some selected membranes in lithium ion batteries. Based on the type of electrolyte used, literature concerning ceramic-glass and polymer solid ion conductors, microporous filter type separators and polymer gel based membranes is reviewed. PMID:24958286

Domain Nucleation Rates and Interfacial Line Tensions in Supported Bilayers of Ternary Mixtures Containing Galactosylceramide

PubMed Central

Blanchette, Craig D.; Lin, Wan-Chen; Orme, Christine A.; Ratto, Timothy V.; Longo, Marjorie L.

2008-01-01

Domains within the plane of the plasma membrane, referred to as membrane rafts, have been a topic of considerable interest in the field of membrane biophysics. Although model membrane systems have been used extensively to study lipid phase behavior as it relates to the existence of rafts, very little work has focused on either the initial stage of lipid domain nucleation, or the relevant physical parameters such as temperature and interfacial line tension which control nucleation. In this work, we utilize a method in which the kinetic process of lipid domain nucleation is imaged by atomic force microscopy and modeled using classical theory of nucleation to map interfacial line tension in ternary lipid mixtures. These mixtures consist of a fluid phase lipid component (1,2-dilauroyl-sn-glycero-3-phosphocholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, or 1,2-dioleoyl-sn-glycero-3-phosphocholine), a solid phase component (galactosylceramide), and cholesterol. Interfacial line tension measurements of galactosylceramide-rich domains track with our previously measured area/perimeter ratios and height mismatches measured here. Line tension also follows known trends in cholesterol interactions and partitioning, as we observed previously with area/perimeter ratios. Our line tension measurements are discussed in combination with recent line tension measurements to address line tension regulation by cholesterol and the dynamic nature of membrane rafts. PMID:18065459

Controlling the orientation of spin-correlated radical pairs by covalent linkage to nanoporous anodic aluminum oxide membranes.

PubMed

Chen, Hsiao-Fan; Gardner, Daniel M; Carmieli, Raanan; Wasielewski, Michael R

2013-10-07

Ordered multi-spin assemblies are required for developing solid-state molecule-based spintronics. A linear donor-chromophore-acceptor (D-C-A) molecule was covalently attached inside the 150 nm diam. nanopores of an anodic aluminum oxide (AAO) membrane. Photoexcitation of D-C-A in a 343 mT magnetic field results in sub-nanosecond, two-step electron transfer to yield the spin-correlated radical ion pair (SCRP) (1)(D(+)˙-C-A(-)˙), which then undergoes radical pair intersystem crossing (RP-ISC) to yield (3)(D(+)˙-C-A(-)˙). RP-ISC results in S-T0 mixing to selectively populate the coherent superposition states |S'> and |T'>. Microwave-induced transitions between these states and the unpopulated |T(+1)> and |T(-1)> states result in spin-polarized time-resolved EPR (TREPR) spectra. The dependence of the electron spin polarization (ESP) phase of the TREPR spectra on the orientation of the AAO membrane pores relative to the externally applied magnetic field is used to determine the overall orientation of the SCRPs within the pores at room temperature.

Heavy metals in handloom-dyeing effluents and their biosorption by agricultural byproducts.

PubMed

Nahar, Kamrun; Chowdhury, Md Abul Khair; Chowdhury, Md Akhter Hossain; Rahman, Afzal; Mohiuddin, K M

2018-03-01

The Madhabdi municipality in the Narsingdi district of Bangladesh is a well-known area for textile, handloom weaving, and dyeing industries. These textile industries produce a considerable amount of effluents, sewage sludge, and solid waste materials every day that they directly discharge into surrounding water bodies and agricultural fields. This disposal poses a serious threat to the overall epidemic and socio-economic pattern of the locality. This research entailed the collection of 34 handloom-dyeing effluent samples from different handloom-dyeing industries of Madhabdi, which were then analyzed to determine the contents of the heavy metals iron (Fe), zinc (Zn), copper (Cu), chromium (Cr), manganese (Mn), lead (Pb), and cadmium (Cd). Average concentrations of Fe, Cr, Cu, Pb, Mn, and Zn were 3.81, 1.35, 1.70, 0.17, 0.75, and 0.73 mg L -1 , respectively, whereas Cd content was below the detectable limit of the atomic adsorption spectrophotometer. The concentrations of Fe, Cr, Cu, Pb, and Mn exceed the industrial effluent discharge standards (IEDS) for inland surface water and irrigation water guideline values. A biosorption experiment of the heavy metals (Fe, Cr, Cu, Mn, and Zn) was conducted without controlling for any experimental parameters (e.g., pH, temperature, or other compounds present in the effluent samples) by using four agricultural wastes or byproducts, namely rice husk, sawdust, lemon peel, and eggshell. Twenty grams of each biosorbent was added to 1 L of effluent samples and stored for 7 days. The biosorption capacity of each biosorbent is ranked as follows: eggshell, sawdust, rice husk, and lemon peel. Furthermore, the biosorption affinity of each metal ion was found in the following order: Cu and Cr (both had similar biosorption affinity), Zn, Fe, Mn. The effluents should not be discharged before treatment, and efficient treatment of effluents is possible with eggshell powder or sawdust at a rate of 20 g of biosorbent per liter of effluents.

UV, VISIBLE AND NIR SPECTRAL ANALYSIS OF EGGSHELLS IN THE CHARADRIIDAE FAMILY OF BIRDS

EPA Science Inventory

We employed reflectance spectrophotometry to quantify color and mineral composition of eggshells from several species of the bird family Charadriidae to characterize species physiology and to distinguish nesting habitat preferences. We used a Shimadzu spectrophotometer to measur...

Dynamic nuclear polarization methods in solids and solutions to explore membrane proteins and membrane systems.

PubMed

Cheng, Chi-Yuan; Han, Songi

2013-01-01

Membrane proteins regulate vital cellular processes, including signaling, ion transport, and vesicular trafficking. Obtaining experimental access to their structures, conformational fluctuations, orientations, locations, and hydration in membrane environments, as well as the lipid membrane properties, is critical to understanding their functions. Dynamic nuclear polarization (DNP) of frozen solids can dramatically boost the sensitivity of current solid-state nuclear magnetic resonance tools to enhance access to membrane protein structures in native membrane environments. Overhauser DNP in the solution state can map out the local and site-specific hydration dynamics landscape of membrane proteins and lipid membranes, critically complementing the structural and dynamics information obtained by electron paramagnetic resonance spectroscopy. Here, we provide an overview of how DNP methods in solids and solutions can significantly increase our understanding of membrane protein structures, dynamics, functions, and hydration in complex biological membrane environments.

Red wine tannins fluidify and precipitate lipid liposomes and bicelles. A role for lipids in wine tasting?

PubMed

Furlan, Aurélien L; Castets, Aurore; Nallet, Frédéric; Pianet, Isabelle; Grélard, Axelle; Dufourc, Erick J; Géan, Julie

2014-05-20

Sensory properties of red wine tannins are bound to complex interactions between saliva proteins, membranes taste receptors of the oral cavity, and lipids or proteins from the human diet. Whereas astringency has been widely studied in terms of tannin-saliva protein colloidal complexes, little is known about interactions between tannins and lipids and their implications in the taste of wine. This study deals with tannin-lipid interactions, by mimicking both oral cavity membranes by micrometric size liposomes and lipid droplets in food by nanometric isotropic bicelles. Deuterium and phosphorus solid-state NMR demonstrated the membrane hydrophobic core disordering promoted by catechin (C), epicatechin (EC), and epigallocatechin gallate (EGCG), the latter appearing more efficient. C and EGCG destabilize isotropic bicelles and convert them into an inverted hexagonal phase. Tannins are shown to be located at the membrane interface and stabilize the lamellar phases. These newly found properties point out the importance of lipids in the complex interactions that happen in the mouth during organoleptic feeling when ingesting tannins.

Dual phase high-temperature membranes for CO2 separation - performance assessment in post- and pre-combustion processes.

PubMed

Anantharaman, Rahul; Peters, Thijs; Xing, Wen; Fontaine, Marie-Laure; Bredesen, Rune

2016-10-20

Dual phase membranes are highly CO 2 -selective membranes with an operating temperature above 400 °C. The focus of this work is to quantify the potential of dual phase membranes in pre- and post-combustion CO 2 capture processes. The process evaluations show that the dual phase membranes integrated with an NGCC power plant for CO 2 capture are not competitive with the MEA process for post-combustion capture. However, dual phase membrane concepts outperform the reference Selexol technology for pre-combustion CO 2 capture in an IGCC process. The two processes evaluated in this work, post-combustion NGCC and pre-combustion IGCC, represent extremes in CO 2 partial pressure fed to the separation unit. Based on the evaluations it is expected that dual phase membranes could be competitive for post-combustion capture from a pulverized coal fired power plant (PCC) and pre-combustion capture from an Integrated Reforming Cycle (IRCC).

An experimental study of perovskite-structured mixed ionic- electronic conducting oxides and membranes

NASA Astrophysics Data System (ADS)

Zeng, Pingying

In recent decades, ceramic membranes based on mixed ionic and electronic conducting (MIEC) perovskite-structured oxides have received many attentions for their applications for air separation, or as a membrane reactor for methane oxidation. While numerous perovskite oxide materials have been explored over the past two decades; there are hardly any materials with sufficient practical economic value and performance for large scale applications, which justifies continuing the search for new materials. The main purposes of this thesis study are: (1) develop several novel SrCoO3-delta based MIEC oxides, SrCoCo1-xMxO3-delta, based on which membranes exhibit excellent oxygen permeability; (2) investigate the significant effects of the species and concentration of the dopants M (metal ions with fixed valences) on the various properties of these membranes; (3) investigate the significant effects of sintering temperature on the microstructures and performance of oxygen permeation membranes; and (4) study the performance of oxygen permeation membranes as a membrane reactor for methane combustion. To stabilize the cubic phase structure of the SrCoO3-delta oxide, various amounts of scandium was doped into the B-site of SrCoO 3-delta to form a series of new perovskite oxides, SrScxCoCo 1-xO3-delta (SSCx, x = 0-0.7). The significant effects of scandium-doping concentration on the phase structure, electrical conductivity, sintering performance, thermal and structural stability, cathode performance, and oxygen permeation performance of the SSCx membranes, were systematically studied. Also for a more in-depth understanding, the rate determination steps for the oxygen transport process through the membranes were clarified by theoretical and experimental investigation. It was found that only a minor amount of scandium (5 mol%) doping into the B-site of SrCoO3-delta can effectively stabilize the cubic phase structure, and thus significantly improve the electrical conductivity and oxygen permeability of the SrCoO3-delta membrane. Among all the disk-shaped SSCx (x = 0-0.7) membranes with a thickness of 0.91 mm, both SSC0.05 and SSC0.1 exhibit the highest oxygen permeation rate of about 3.2 mL.cm-2.min-1 (STP) at 900 °C, SSC0.1 also shows excellent cathode performance for a solid oxide fuel cell. Therefore SSC0.1 is of special interest, and thus investigated regarding the performance as a membrane reactor for methane combustion. The performance was evaluated based on the results of methane conversion rates and CO 2 selectivity. Inspired by the above findings, a series of mixed-conducting perovskite oxides SrCo0.95M0.05O3-delta (SCM, M = Bi5+, Zr4+, Ce4+, Sc3+ , La3+, Y3+, Al3+, Zn 2+) were prepared to study the effects of different dopants M on the performance of SrCo0.95M0.05O3-delta. It was found that the M cations significantly affect the crystal phase structure, grain growth, membrane porosity, electrical conductivity, and the oxygen permeability of the SCM membranes. Specifically, it is postulated in this study that the formation of the cubic perovskite structure is dependent on the electron configuration in the outer orbits of M cations, which may provide theoretical guidance for future development of high oxygen permeation ceramic membranes based on the perovskite materials. To study the significant effects of grain sizes on the oxygen permeation behaviors of La0.6Sr0.4Co0.2Fe0.8O3-delta (LSCF) and SrSc0.1Co0.9O 3-delta (SSC0.1) membranes, the LSCF and SSC0.1 membranes were sintered at various temperatures to form different microstructures. Properties of these membranes with varied grain sizes were compared. Results showed that the oxygen permeation rate of the LSCF membrane increases with increasing the grain size, however, it is interesting that the oxygen permeation rate of the SSC0.1 membrane decreases with increasing the grain size. This implies that oxygen transport occurs more, however, less rapidly along grain boundaries than through the bulks in the LSCF and SSC0.1 membranes, respectively. A LSCF hollow fiber membrane and a SSC0.1 planar membrane were applied as membrane reactors for methane combustion. To improve their performances, LSCF powder and SSC0.1 powder were dip-coated and spray-coated on the permeation sides of LSCF hollow fiber membranes and SSC0.1 planar membranes, respectively. The exhaust gas components were analyzed by Gas Chromatography (GC). The performance was evaluated based on the results of methane conversion rates and CO 2 selectivity. The highest CO2 selectivity of the LSCF hollow fiber membrane and the SSC0.1 planar membrane is about 88 and 85 %, respectively. This indicates that the application of an oxygen permeation membrane as methane combustion reactor is feasible.

Darker eggs of mosquitoes resist more to dry conditions: Melanin enhances serosal cuticle contribution in egg resistance to desiccation in Aedes, Anopheles and Culex vectors.

PubMed

Farnesi, Luana C; Vargas, Helena C M; Valle, Denise; Rezende, Gustavo L

2017-10-01

Mosquito vectors lay their white eggs in the aquatic milieu. During early embryogenesis water passes freely through the transparent eggshell, which at this moment is composed of exochorion and endochorion. Within two hours the endochorion darkens via melanization but even so eggs shrink and perish if removed from moisture. However, during mid-embryogenesis, cells of the extraembryonic serosa secrete the serosal cuticle, localized right below the endochorion, becoming the third and innermost eggshell layer. Serosal cuticle formation greatly reduces water flow and allows egg survival outside the water. The degree of egg resistance to desiccation (ERD) at late embryogenesis varies among different species: Aedes aegypti, Anopheles aquasalis and Culex quinquefasciatus eggs can survive in a dry environment for ≥ 72, 24 and 5 hours, respectively. In some adult insects, darker-body individuals show greater resistance to desiccation than lighter ones. We asked if egg melanization enhances mosquito serosal cuticle-dependent ERD. Species with higher ERD at late embryogenesis exhibit more melanized eggshells. The melanization-ERD hypothesis was confirmed employing two Anopheles quadrimaculatus strains, the wild type and the mutant GORO, with a dark-brown and a golden eggshell, respectively. In all cases, serosal cuticle formation is fundamental for the establishment of an efficient ERD but egg viability outside the water is much higher in mosquitoes with darker eggshells than in those with lighter ones. The finding that pigmentation influences egg water balance is relevant to understand the evolutionary history of insect egg coloration. Since eggshell and adult cuticle pigmentation ensure insect survivorship in some cases, they should be considered regarding species fitness and novel approaches for vector or pest insects control.

Darker eggs of mosquitoes resist more to dry conditions: Melanin enhances serosal cuticle contribution in egg resistance to desiccation in Aedes, Anopheles and Culex vectors

PubMed Central

Farnesi, Luana C.; Vargas, Helena C. M.; Valle, Denise

2017-01-01

Mosquito vectors lay their white eggs in the aquatic milieu. During early embryogenesis water passes freely through the transparent eggshell, which at this moment is composed of exochorion and endochorion. Within two hours the endochorion darkens via melanization but even so eggs shrink and perish if removed from moisture. However, during mid-embryogenesis, cells of the extraembryonic serosa secrete the serosal cuticle, localized right below the endochorion, becoming the third and innermost eggshell layer. Serosal cuticle formation greatly reduces water flow and allows egg survival outside the water. The degree of egg resistance to desiccation (ERD) at late embryogenesis varies among different species: Aedes aegypti, Anopheles aquasalis and Culex quinquefasciatus eggs can survive in a dry environment for ≥ 72, 24 and 5 hours, respectively. In some adult insects, darker-body individuals show greater resistance to desiccation than lighter ones. We asked if egg melanization enhances mosquito serosal cuticle-dependent ERD. Species with higher ERD at late embryogenesis exhibit more melanized eggshells. The melanization-ERD hypothesis was confirmed employing two Anopheles quadrimaculatus strains, the wild type and the mutant GORO, with a dark-brown and a golden eggshell, respectively. In all cases, serosal cuticle formation is fundamental for the establishment of an efficient ERD but egg viability outside the water is much higher in mosquitoes with darker eggshells than in those with lighter ones. The finding that pigmentation influences egg water balance is relevant to understand the evolutionary history of insect egg coloration. Since eggshell and adult cuticle pigmentation ensure insect survivorship in some cases, they should be considered regarding species fitness and novel approaches for vector or pest insects control. PMID:29084225

Trace elements in feathers and eggshells of brown booby Sula leucogaster in the Marine National Park of Currais Islands, Brazil.

PubMed

Dolci, Natiely Natalyane; Sá, Fabian; da Costa Machado, Eunice; Krul, Ricardo; Rodrigues Neto, Renato

2017-09-10

Levels of trace elements were investigated in feathers of 51 adults and 47 eggshells of brown boobies Sula leucogaster from one bird colony in the Marine National Park of Currais Islands, Brazil, between December 2013 and October 2014. Average concentrations (μg g -1 , dry weight) in feathers and eggshells, respectively, were Al 50.62-9.58, As 0.35-2.37, Cd 0.05-0.03, Co 0.38-2.1, Cu 15.12-0.99, Fe 47.47-22.92, Mg 815.71-1116.92, Ni 0.29-11.85, and Zn 94.16-1.98. In both arrays, the average concentration of Mg was the highest among all the elements analyzed, while the lowest was recorded for Cd. As and Ni presented levels at which biological impacts might occur. Zn concentrations were higher than those considered normal in other organs. Levels of Al, Fe, Cu, Zn, and Cd were higher in feathers, whereas higher contents of Mg, Co, Ni, and As occurred in eggshells. The comparison between the elements in eggshells collected at different seasons showed no significant difference (p > 0.05) due, probably, to the lack of temporal variation on foraging behavior and/or on bioavailability of trace elements. Metals and arsenic in feathers and eggshells were mostly not correlated. Future studies on Paraná coast should focus on the speciation of the elements, especially As, Ni, and Zn, which proved to be a possible problem for the environment and biota. It is necessary to investigate both matrices, shell and internal contents of the eggs, in order to verify if the differences previously reported in other studies also occur in eggs of brown boobies in the Marine National Park of Currais Islands.

Intra-clutch and inter-colony variability in element concentrations in eggshells of the black-headed gull, Chroicocephalus ridibundus, in northern Poland.

PubMed

Kitowski, Ignacy; Indykiewicz, Piotr; Wiącek, Dariusz; Jakubas, Dariusz

2017-04-01

Eggshells are good bioindicators of environmental contamination, and therefore, the concentrations of 17 trace elements in 87 eggshells of black-headed gulls, Chroicocephalus ridibundus, were determined in five breeding colonies in an area dominated by farmland in northern Poland. The intra-clutch variability in the eggshell concentrations of heavy metals and other elements was also investigated, and the concentrations of the elements showed the following pattern: Ca > Mg > Sr > Fe > Zn > Al > Cr > Se > Mn > Cu > Pb > As > Ni > Mo = V > Sc > Cd. The concentrations of Fe, Al, and Mn decreased with the order in which the eggs were laid, but Sr concentrations increased. In contrast, the concentration of Cu significantly increased with the laying date. The concentrations of all elements significantly differed among the studied colonies; the highest concentration of eight elements was found in the eggshells from the Kusowo colony, which may have resulted from the intensive use of fertilizers, manure, and slurry in the surrounding agricultural region. The concentrations of Mg, Sr, and Zn in the eggshells from Skoki Duże were higher than those of the other studied colonies, which may have occurred because the gulls were nesting in a functioning gravel pit; soil and the parent rock are natural reservoirs of these elements. The observed element levels indicate that the environment where the black-headed gull eggs were formed, i.e., primarily near the breeding colonies, remains in a relatively unpolluted state, which was reflected by the low levels of Cd, Ni, and Pb and the lack of measurable levels of Hg.

Feasibility of sulfate-calcined eggshells for removing pathogenic bacteria and antibiotic resistance genes from landfill leachates.

PubMed

Ye, Mao; Sun, Mingming; Chen, Xu; Feng, Yanfang; Wan, Jinzhong; Liu, Kuan; Tian, Da; Liu, Manqiang; Wu, Jun; Schwab, Arthur P; Jiang, Xin

2017-05-01

High abundance of human pathogen and antibiotic resistance genes (ARGs) in landfill leachate has become an emerging threat against human health. Therefore, sulfate- and calcination-modified eggshells as green agricultural bioresource were applied to test the feasibility of removing pathogenic bacteria and ARGs from leachate. The highest removal of Escherichia coli (E. coil) and gentamycin resistant gene (gmrA) from artificial contaminated landfill leachate was achieved by the application of eggshell with combined treatment of sulfate and calcination. The 16S and gmrA gene copies of E. coil declined significantly from 1.78E8±8.7E6 and 4.12E8±5.9E6 copies mL -1 to 1.32E7±2.6E6 and 2.69E7±7.2E6 copies mL -1 , respectively, within 24h dynamic adsorption equilibrium process (p<0.05). Moreover, according to the Langmuir kinetic model, the greatest adsorption amount (1.56×10 9 CFU E. coil per gram of modified eggshells) could be obtained at neutral pH of 7.5. The optimal adsorption eggshells were then screened to the further application in three typical landfill leachates in Nanjing, eastern China. Significant decrease in species and abundance of pathogenic bacteria and ARGs (tet, sul, erm, qnr, and ampC) indicated its great efficiency to purify landfill leachates. This study demonstrated that sulfate-calcined eggshells can be an environmentally-friendly and highly efficient bioadsorbent to the management of reducing dissemination risk of pathogen and ARGs in landfill leachate. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multiple Locations of Peptides in the Hydrocarbon Core of Gel-Phase Membranes Revealed by Peptide 13C to Lipid 2H Rotational-Echo Double-Resonance Solid-State Nuclear Magnetic Resonance

PubMed Central

2015-01-01

Membrane locations of peptides and proteins are often critical to their functions. Solid-state rotational-echo double-resonance (REDOR) nuclear magnetic resonance is applied to probe the locations of two peptides via peptide 13CO to lipid 2H distance measurements. The peptides are KALP, an α-helical membrane-spanning peptide, and HFP, the β-sheet N-terminal fusion peptide of the HIV gp41 fusion protein that plays an important role in HIV–host cell membrane fusion. Both peptides are shown to have at least two distinct locations within the hydrocarbon core of gel-phase membranes. The multiple locations are attributed to snorkeling of lysine side chains for KALP and to the distribution of antiparallel β-sheet registries for HFP. The relative population of each location is also quantitated. To the best of our knowledge, this is the first clear experimental support of multiple peptide locations within the membrane hydrocarbon core. These data are for gel-phase membranes, but the approach should work for liquid-ordered membranes containing cholesterol and may be applicable to liquid-disordered membranes with appropriate additional analysis to take into account protein and lipid motion. This paper also describes the methodological development of 13CO–2H REDOR using the lyophilized I4 peptide that is α-helical and 13CO-labeled at A9 and 2Hα-labeled at A8. The I4 spins are well-approximated as an ensemble of isolated 13CO–2H spin pairs each separated by 5.0 Å with a 37 Hz dipolar coupling. A pulse sequence with rectangular 100 kHz 2H π pulses results in rapid and extensive buildup of REDOR (ΔS/S0) with a dephasing time (τ). The buildup is well-fit by a simple exponential function with a rate of 24 Hz and an extent close to 1. These parameter values reflect nonradiative transitions between the 2H spin states during the dephasing period. Each spin pair spends approximately two-thirds of its time in the 13CO–2H (m = ±1) states and approximately one-third of its time in the 13CO–2H (m = 0) state and contributes to the ΔS/S0 buildup during the former but not the latter time segments. PMID:25531389

Static charge outside chamber induces dielectric breakdown of solid-state nanopore membranes

NASA Astrophysics Data System (ADS)

Matsui, Kazuma; Goto, Yusuke; Yanagi, Itaru; Yanagawa, Yoshimitsu; Ishige, Yu; Takeda, Ken-ichi

2018-04-01

Reducing device capacitance is effective for decreasing current noise observed in a solid-state nanopore-based DNA sequencer. On the other hand, we have recently found that voltage stress causes pinhole-like defects in such low-capacitance devices. The origin of voltage stress, however, has not been determined. In this research, we identified that a dominant origin is static charge on the outer surface of a flow cell. Even though the outer surface was not in direct contact with electrolytes in the flow cell, the charge induces high voltage stress on a membrane according to the capacitance coupling ratio of the flow cell to the membrane.

Integrating De Novo Transcriptome Assembly and Cloning to Obtain Chicken Ovocleidin-17 Full-Length cDNA

PubMed Central

Ning, ZhongHua; Hincke, Maxwell T.; Yang, Ning; Hou, ZhuoCheng

2014-01-01

Efficiently obtaining full-length cDNA for a target gene is the key step for functional studies and probing genetic variations. However, almost all sequenced domestic animal genomes are not ‘finished’. Many functionally important genes are located in these gapped regions. It can be difficult to obtain full-length cDNA for which only partial amino acid/EST sequences exist. In this study we report a general pipeline to obtain full-length cDNA, and illustrate this approach for one important gene (Ovocleidin-17, OC-17) that is associated with chicken eggshell biomineralization. Chicken OC-17 is one of the best candidates to control and regulate the deposition of calcium carbonate in the calcified eggshell layer. OC-17 protein has been purified, sequenced, and has had its three-dimensional structure solved. However, researchers still cannot conduct OC-17 mRNA related studies because the mRNA sequence is unknown and the gene is absent from the current chicken genome. We used RNA-Seq to obtain the entire transcriptome of the adult hen uterus, and then conducted de novo transcriptome assembling with bioinformatics analysis to obtain candidate OC-17 transcripts. Based on this sequence, we used RACE and PCR cloning methods to successfully obtain the full-length OC-17 cDNA. Temporal and spatial OC-17 mRNA expression analyses were also performed to demonstrate that OC-17 is predominantly expressed in the adult hen uterus during the laying cycle and barely at immature developmental stages. Differential uterine expression of OC-17 was observed in hens laying eggs with weak versus strong eggshell, confirming its important role in the regulation of eggshell mineralization and providing a new tool for genetic selection for eggshell quality parameters. This study is the first one to report the full-length OC-17 cDNA sequence, and builds a foundation for OC-17 mRNA related studies. We provide a general method for biologists experiencing difficulty in obtaining candidate gene full-length cDNA sequences. PMID:24676480

Dinosaur origin of egg color: oviraptors laid blue-green eggs

PubMed Central

Yang, Tzu-Ruei; Sander, Philipp N.; Schneider, Marion; Engeser, Marianne; Kath-Schorr, Stephanie; Müller, Christa E.; Sander, P. Martin

2017-01-01

Protoporphyrin (PP) and biliverdin (BV) give rise to the enormous diversity in avian egg coloration. Egg color serves several ecological purposes, including post-mating signaling and camouflage. Egg camouflage represents a major character of open-nesting birds which accomplish protection of their unhatched offspring against visually oriented predators by cryptic egg coloration. Cryptic coloration evolved to match the predominant shades of color found in the nesting environment. Such a selection pressure for the evolution of colored or cryptic eggs should be present in all open nesting birds and relatives. Many birds are open-nesting, but protect their eggs by continuous brooding, and thus exhibit no or minimal eggshell pigmentation. Their closest extant relatives, crocodiles, protect their eggs by burial and have unpigmented eggs. This phylogenetic pattern led to the assumption that colored eggs evolved within crown birds. The mosaic evolution of supposedly avian traits in non-avian theropod dinosaurs, however, such as the supposed evolution of partially open nesting behavior in oviraptorids, argues against this long-established theory. Using a double-checking liquid chromatography ESI-Q-TOF mass spectrometry routine, we traced the origin of colored eggs to their non-avian dinosaur ancestors by providing the first record of the avian eggshell pigments protoporphyrin and biliverdin in the eggshells of Late Cretaceous oviraptorid dinosaurs. The eggshell parataxon Macroolithus yaotunensis can be assigned to the oviraptor Heyuannia huangi based on exceptionally preserved, late developmental stage embryo remains. The analyzed eggshells are from three Late Cretaceous fluvial deposits ranging from eastern to southernmost China. Reevaluation of these taphonomic settings, and a consideration of patterns in the porosity of completely preserved eggs support an at least partially open nesting behavior for oviraptorosaurs. Such a nest arrangement corresponds with our reconstruction of blue-green eggs for oviraptors. According to the sexual signaling hypothesis, the reconstructed blue-green eggs support the origin of previously hypothesized avian paternal care in oviraptorid dinosaurs. Preserved dinosaur egg color not only pushes the current limits of the vertebrate molecular and associated soft tissue fossil record, but also provides a perspective on the potential application of this unexplored paleontological resource. PMID:28875070

Dinosaur origin of egg color: oviraptors laid blue-green eggs.

PubMed

Wiemann, Jasmina; Yang, Tzu-Ruei; Sander, Philipp N; Schneider, Marion; Engeser, Marianne; Kath-Schorr, Stephanie; Müller, Christa E; Sander, P Martin

2017-01-01

Protoporphyrin (PP) and biliverdin (BV) give rise to the enormous diversity in avian egg coloration. Egg color serves several ecological purposes, including post-mating signaling and camouflage. Egg camouflage represents a major character of open-nesting birds which accomplish protection of their unhatched offspring against visually oriented predators by cryptic egg coloration. Cryptic coloration evolved to match the predominant shades of color found in the nesting environment. Such a selection pressure for the evolution of colored or cryptic eggs should be present in all open nesting birds and relatives. Many birds are open-nesting, but protect their eggs by continuous brooding, and thus exhibit no or minimal eggshell pigmentation. Their closest extant relatives, crocodiles, protect their eggs by burial and have unpigmented eggs. This phylogenetic pattern led to the assumption that colored eggs evolved within crown birds. The mosaic evolution of supposedly avian traits in non-avian theropod dinosaurs, however, such as the supposed evolution of partially open nesting behavior in oviraptorids, argues against this long-established theory. Using a double-checking liquid chromatography ESI-Q-TOF mass spectrometry routine, we traced the origin of colored eggs to their non-avian dinosaur ancestors by providing the first record of the avian eggshell pigments protoporphyrin and biliverdin in the eggshells of Late Cretaceous oviraptorid dinosaurs. The eggshell parataxon Macroolithus yaotunensis can be assigned to the oviraptor Heyuannia huangi based on exceptionally preserved, late developmental stage embryo remains. The analyzed eggshells are from three Late Cretaceous fluvial deposits ranging from eastern to southernmost China. Reevaluation of these taphonomic settings, and a consideration of patterns in the porosity of completely preserved eggs support an at least partially open nesting behavior for oviraptorosaurs. Such a nest arrangement corresponds with our reconstruction of blue-green eggs for oviraptors. According to the sexual signaling hypothesis, the reconstructed blue-green eggs support the origin of previously hypothesized avian paternal care in oviraptorid dinosaurs. Preserved dinosaur egg color not only pushes the current limits of the vertebrate molecular and associated soft tissue fossil record, but also provides a perspective on the potential application of this unexplored paleontological resource.

Integrating de novo transcriptome assembly and cloning to obtain chicken Ovocleidin-17 full-length cDNA.

PubMed

Zhang, Quan; Liu, Long; Zhu, Feng; Ning, ZhongHua; Hincke, Maxwell T; Yang, Ning; Hou, ZhuoCheng

2014-01-01

Efficiently obtaining full-length cDNA for a target gene is the key step for functional studies and probing genetic variations. However, almost all sequenced domestic animal genomes are not 'finished'. Many functionally important genes are located in these gapped regions. It can be difficult to obtain full-length cDNA for which only partial amino acid/EST sequences exist. In this study we report a general pipeline to obtain full-length cDNA, and illustrate this approach for one important gene (Ovocleidin-17, OC-17) that is associated with chicken eggshell biomineralization. Chicken OC-17 is one of the best candidates to control and regulate the deposition of calcium carbonate in the calcified eggshell layer. OC-17 protein has been purified, sequenced, and has had its three-dimensional structure solved. However, researchers still cannot conduct OC-17 mRNA related studies because the mRNA sequence is unknown and the gene is absent from the current chicken genome. We used RNA-Seq to obtain the entire transcriptome of the adult hen uterus, and then conducted de novo transcriptome assembling with bioinformatics analysis to obtain candidate OC-17 transcripts. Based on this sequence, we used RACE and PCR cloning methods to successfully obtain the full-length OC-17 cDNA. Temporal and spatial OC-17 mRNA expression analyses were also performed to demonstrate that OC-17 is predominantly expressed in the adult hen uterus during the laying cycle and barely at immature developmental stages. Differential uterine expression of OC-17 was observed in hens laying eggs with weak versus strong eggshell, confirming its important role in the regulation of eggshell mineralization and providing a new tool for genetic selection for eggshell quality parameters. This study is the first one to report the full-length OC-17 cDNA sequence, and builds a foundation for OC-17 mRNA related studies. We provide a general method for biologists experiencing difficulty in obtaining candidate gene full-length cDNA sequences.

Stir-bar supported micro-solid-phase extraction for the determination of polychlorinated biphenyl congeners in serum samples.

PubMed

Sajid, Muhammad; Basheer, Chanbasha

2016-07-15

In present work, a new configuration of micro-solid phase extraction was introduced and termed as stir-bar supported micro-solid-phase extraction (SB-μ-SPE). A tiny stir-bar was packed inside the porous polypropylene membrane along with sorbent material and the edges of membrane sheet were heat sealed to secure the contents. The packing of stir-bar inside the μ-SPE device does not allow the device to stick with the wall or any corner of the sample vial during extraction, which is, however, a frequent observation in routine μ-SPE. Moreover, it enhances effective surface area of the sorbent exposed to sample solution through continuous agitation (motion and rotation). It also completely immerses the SB-μ-SPE device in the sample solution even for non-polar sorbents. Polychlorinated biphenyls (PCBs) were selected as model compounds and the method performance was evaluated in human serum samples. After extraction, samples were analyzed by gas chromatography mass spectrometry (GC-MS). The factors that affect extraction efficiency of SB-μ-SPE were optimized. Under optimum conditions, a good linearity (0.1-100ngmL(-1)) with coefficients of determinations ranging from 0.9868 to 0.9992 was obtained. Limits of detections were ranged between 0.003 and 0.047ngmL(-1). Acceptable values for inter-day (3.2-9.1%) and intra-day (3.1-7.2%) relative standard deviations were obtained. The optimized method was successfully applied to determine the concentration of PCB congeners in human serum samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Three-Dimensional Microphase Separation and Synergistic Permeability in Stacked Lipid–Polymer Hybrid Membranes

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

Kang, Minjee; Lee, Byeongdu; Leal, Cecilia

Here, we present new structures of soft-material thin films that augment the functionality of substrate-mediated delivery systems. A hybrid material composed of phospholipids and block copolymers adopts a multilayered membrane structure supported on a solid surface. The hybrid films comprise intentional intramembrane heterogeneities that register across multilayers. These stacked domains convey unprecedented enhancement and control of permeability of solutes across micrometer-thick films. Using grazing incidence X-ray scattering, phase contrast atomic force microscopy, and confocal microscopy, we observed that in each lamella, lipid and polymers partition unevenly within the membrane plane segregating into lipid- or polymer-rich domains. Interestingly, we found evidencemore » that like-domains align in registry across multilayers, thereby making phase separation three-dimensional. Phase boundaries exist over extended length scales to compensate the height mismatch between lipid and polymer molecules. We show that microphase separation in hybrid films can be exploited to augment the capability of drug-eluting substrates. Lipid–polymer hybrid films loaded with paclitaxel show synergistic permeability of drug compared to single-component counterparts. We present a thorough structural study of stacked lipid–polymer hybrid membranes and propose that the presence of registered domains and domain boundaries impart enhanced drug release functionality. This work offers new perspectives in designing thin films for controlled delivery applications« less

Three-Dimensional Microphase Separation and Synergistic Permeability in Stacked Lipid–Polymer Hybrid Membranes

DOE PAGES

Kang, Minjee; Lee, Byeongdu; Leal, Cecilia

2017-10-20

Here, we present new structures of soft-material thin films that augment the functionality of substrate-mediated delivery systems. A hybrid material composed of phospholipids and block copolymers adopts a multilayered membrane structure supported on a solid surface. The hybrid films comprise intentional intramembrane heterogeneities that register across multilayers. These stacked domains convey unprecedented enhancement and control of permeability of solutes across micrometer-thick films. Using grazing incidence X-ray scattering, phase contrast atomic force microscopy, and confocal microscopy, we observed that in each lamella, lipid and polymers partition unevenly within the membrane plane segregating into lipid- or polymer-rich domains. Interestingly, we found evidencemore » that like-domains align in registry across multilayers, thereby making phase separation three-dimensional. Phase boundaries exist over extended length scales to compensate the height mismatch between lipid and polymer molecules. We show that microphase separation in hybrid films can be exploited to augment the capability of drug-eluting substrates. Lipid–polymer hybrid films loaded with paclitaxel show synergistic permeability of drug compared to single-component counterparts. We present a thorough structural study of stacked lipid–polymer hybrid membranes and propose that the presence of registered domains and domain boundaries impart enhanced drug release functionality. This work offers new perspectives in designing thin films for controlled delivery applications« less

Isotopic ordering in eggshells reflects body temperatures and suggests differing thermophysiology in two Cretaceous dinosaurs.

PubMed

Eagle, Robert A; Enriquez, Marcus; Grellet-Tinner, Gerald; Pérez-Huerta, Alberto; Hu, David; Tütken, Thomas; Montanari, Shaena; Loyd, Sean J; Ramirez, Pedro; Tripati, Aradhna K; Kohn, Matthew J; Cerling, Thure E; Chiappe, Luis M; Eiler, John M

2015-10-13

Our understanding of the evolutionary transitions leading to the modern endothermic state of birds and mammals is incomplete, partly because tools available to study the thermophysiology of extinct vertebrates are limited. Here we show that clumped isotope analysis of eggshells can be used to determine body temperatures of females during periods of ovulation. Late Cretaceous titanosaurid eggshells yield temperatures similar to large modern endotherms. In contrast, oviraptorid eggshells yield temperatures lower than most modern endotherms but ∼ 6 °C higher than co-occurring abiogenic carbonates, implying that this taxon did not have thermoregulation comparable to modern birds, but was able to elevate its body temperature above environmental temperatures. Therefore, we observe no strong evidence for end-member ectothermy or endothermy in the species examined. Body temperatures for these two species indicate that variable thermoregulation likely existed among the non-avian dinosaurs and that not all dinosaurs had body temperatures in the range of that seen in modern birds.

A nanostructural basis for gloss of avian eggshells

PubMed Central

Igic, Branislav; Fecheyr-Lippens, Daphne; Xiao, Ming; Chan, Andrew; Hanley, Daniel; Brennan, Patricia R. L.; Grim, Tomas; Waterhouse, Geoffrey I. N.; Hauber, Mark E.; Shawkey, Matthew D.

2015-01-01

The role of pigments in generating the colour and maculation of birds' eggs is well characterized, whereas the effects of the eggshell's nanostructure on the visual appearance of eggs are little studied. Here, we examined the nanostructural basis of glossiness of tinamou eggs. Tinamou eggs are well known for their glossy appearance, but the underlying mechanism responsible for this optical effect is unclear. Using experimental manipulations in conjunction with angle-resolved spectrophotometry, scanning electron microscopy, atomic force microscopy and chemical analyses, we show that the glossy appearance of tinamou eggshells is produced by an extremely smooth cuticle, composed of calcium carbonate, calcium phosphate and, potentially, organic compounds such as proteins and pigments. Optical calculations corroborate surface smoothness as the main factor producing gloss. Furthermore, we reveal the presence of weak iridescence on eggs of the great tinamou (Tinamus major), an optical effect never previously documented for bird eggs. These data highlight the need for further exploration into the nanostructural mechanisms for the production of colour and other optical effects of avian eggshells. PMID:25505139

Calcined Eggshell Waste for Mitigating Soil Antibiotic-Resistant Bacteria/Antibiotic Resistance Gene Dissemination and Accumulation in Bell Pepper.

PubMed

Ye, Mao; Sun, Mingming; Feng, Yanfang; Li, Xu; Schwab, Arthur P; Wan, Jinzhong; Liu, Manqiang; Tian, Da; Liu, Kuan; Wu, Jun; Jiang, Xin

2016-07-13

The combined accumulation of antibiotics, heavy metals, antibiotic-resistant bacteria (ARB)/antibiotic resistance genes (ARGs) in vegetables has become a new threat to human health. This is the first study to investigate the feasibility of calcined eggshells modified by aluminum sulfate as novel agricultural wastes to impede mixed contaminants from transferring to bell pepper (Capsicum annuum L.). In this work, calcined eggshell amendment mitigated mixed pollutant accumulation in bell pepper significantly, enhanced the dissipation of soil tetracycline, sulfadiazine, roxithromycin, and chloramphenicol, decreased the water-soluble fractions of antibiotics, and declined the diversity of ARB/ARGs inside the vegetable. Moreover, quantitative polymerase chain reaction analysis detected that ARG levels in the bell pepper fruits significantly decreased to 10(-10) copies/16S copies, indicating limited risk of ARGs transferring along the food chain. Furthermore, the restoration of soil microbial biological function suggests that calcined eggshell is an environmentally friendly amendment to control the dissemination of soil ARB/ARGs in the soil-vegetable system.

Antimicrobial properties of a nanostructured eggshell from a compost-nesting bird.

PubMed

D'Alba, Liliana; Jones, Darryl N; Badawy, Hope T; Eliason, Chad M; Shawkey, Matthew D

2014-04-01

Infection is an important source of mortality for avian embryos but parental behaviors and eggs themselves can provide a network of antimicrobial defenses. Mound builders (Aves: Megapodiidae) are unique among birds in that they produce heat for developing embryos not by sitting on eggs but by burying them in carefully tended mounds of soil and microbially decomposing vegetation. The low infection rate of eggs of one species in particular, the Australian brush-turkey (Alectura lathami), suggests that they possess strong defensive mechanisms. To identify some of these mechanisms, we first quantified antimicrobial albumen proteins and characterized eggshell structure, finding that albumen was not unusually antimicrobial, but that eggshell cuticle was composed of nanometer-sized calcite spheres. Experimental tests revealed that these modified eggshells were significantly more hydrophobic and better at preventing bacterial attachment and penetration into the egg contents than chicken eggs. Our results suggest that these mechanisms may contribute to the antimicrobial defense system of these eggs, and may provide inspiration for new biomimetic anti-fouling surfaces.

Composite membranes for alkaline electrolysis based on polysulfone and mineral fillers

NASA Astrophysics Data System (ADS)

Burnat, Dariusz; Schlupp, Meike; Wichser, Adrian; Lothenbach, Barbara; Gorbar, Michal; Züttel, Andreas; Vogt, Ulrich F.

2015-09-01

Mineral-based membranes for high temperature alkaline electrolysis were developed by a phase inversion process with polysulfone as binder. The long-term stability of new mineral fillers: wollastonite, forsterite and barite was assessed by 8000 h-long leaching experiments (5.5 M KOH, 85 °C) combined with thermodynamic modelling. Barite has released only 6.22 10-4 M of Ba ions into the electrolyte and was selected as promising filler material, due to its excellent stability. Barite-based membranes, prepared by the phase inversion process, were further studied. The resistivity of these membranes in 5.5 M KOH was investigated as a function of membrane thickness and total porosity, hydrodynamic porosity as well as gas purities determined by conducting electrolysis at ambient conditions. It was found that a dense top layer resulting from the phase inversion process, shows resistivity values up to 451.0 ± 22 Ω cm, which is two orders of magnitude higher than a porous bulk membrane microstructure (3.89 Ω cm). Developed membranes provided hydrogen purity of 99.83 at 200 mA cm-2, which is comparable to previously used chrysotile membranes and higher than commercial state-of-the-art Zirfon 500utp membrane. These cost-effective polysulfone - barite membranes are promising candidates as asbestos replacement for commercial applications.

Effects of electrical field on hatchability performance of eggs from a layer-type breeder.

PubMed

Shafey, T M; Al-Batshan, H A; Ghannam, M M

2007-04-01

1. Eggs from a layer-type breeder flock (Baladi, King Saud University) between 50 and 63 weeks of age were used in three trials to study the effects of electrical field (EF) during incubation on albumen and yolk heights, incubation temperature, egg weight loss and hatchability traits. The effects of egg size and eggshell characteristics on hatchability traits of eggs incubated under EF were investigated. 2. Eggs were weighed and graded into three weight classes (small, medium, and large). The physical dimensions, eggshell characteristics, and conductance of eggs were examined. The incubator was divided into two compartments for the control and EF treatments. Two aluminium plates were fitted on the inside walls of the EF compartment, face to face, and connected to a step up electric transformer. Eggs were exposed constantly to the EF during the first 18 d of incubation at the level of 30 kV/m, 60 Hz. 3. Egg size influenced the physical dimensions and eggshell characteristics of eggs. Large eggs had higher egg weight, egg surface area, egg volume, eggshell conductance, and eggshell weight and lower yolk weight percentage than medium or small size eggs. Small eggs had lower egg length and higher egg density than large or medium size eggs. Large eggs had higher eggshell thickness than small size eggs. 4. EF incubation of eggs raised incubation temperature by 0.06 degrees C, and increased the percentage of egg weight loss, hatchability, and weight of hatching chicks and reduced the early embryo deaths, and length of incubation by approximately 9.8, 19.6, 1.7, 62.1 and 2.1%, respectively. 5. There was no significant difference between the two incubation treatments in the heights of albumen and yolk of incubated eggs, percentages of late embryo deaths, and pips with live and dead embryos. Hatchability traits were not significantly influenced by egg size. 6. It was concluded that EF incubation of eggs increased hatchability, chick-hatching weight, and reduced the length of incubation of Baladi eggs. Differences in the physical dimensions and eggshell characteristics of eggs did not influence hatchability traits of eggs under EF incubation.

Modification of structure and pattern of lipid monolayer on water and solid surfaces in presence of globular protein

NASA Astrophysics Data System (ADS)

Sah, Bijay Kumar; Kundu, Sarathi

2017-05-01

Langmuir monolayers of phospholipids at the air-water interface are well-established model systems for mimicking biological membranes and hence are useful for studying lipid-protein interactions. In the present work, phases and phase transformations occurring in the lipid (DMPA) monolayer in the presence of globular protein (BSA) at neutral subphase pH (≈7.0) are highlighted and the corresponding in-plane pattern and morphology are explored from the surface pressure (π) - specific molecular area (A) isotherm, Brewster angle microscopy (BAM) and atomic force microscopy (AFM) both at air-water and air-solid interfaces. Films of pure lipid and lipid-protein complexes are deposited on solid surfaces by Langmuir-Blodgett method. Due to the presence of BSA molecules, phases and domain pattern changes in comparison with that of the pure DMPA. Moreover, accumulations of globular proteins in between lipid domains are also visible through BAM. AFM shows that the mixed film has relatively bigger globular-like morphology in comparison with that of pure DMPA domains. Combination of electrostatic and hydrophobic interactions between protein and lipid are responsible for such modifications.

Conformational Plasticity of the Cell-Penetrating Peptide SAP As Revealed by Solid-State 19F-NMR and Circular Dichroism Spectroscopies.

PubMed

Afonin, Sergii; Kubyshkin, Vladimir; Mykhailiuk, Pavel K; Komarov, Igor V; Ulrich, Anne S

2017-07-13

The cell-penetrating peptide SAP, which was designed as an amphipathic poly-l-proline helix II (PPII), was suggested to self-assemble into regular fibrils that are relevant for its internalization. Herein we have analyzed the structure of SAP in the membrane-bound state by solid-state 19 F-NMR, which revealed other structural states, in addition to the expected surface-aligned PPII. Trifluoromethyl-bicyclopentyl-glycine (CF 3 -Bpg) and two rigid isomers of trifluoromethyl-4,5-methanoprolines (CF 3 -MePro) were used as labels for 19 F-NMR analysis. The equilibria between different conformations of SAP were studied and were found to be shifted by the substituents at Pro-11. Synchrotron-CD results suggested that substituting Pro-11 by CF 3 -MePro governed the coil-to-PPII equilibrium in solution and in the presence of a lipid bilayer. Using CD and 19 F-NMR, we examined the slow kinetics of the association of SAP with membranes and the dependence of the SAP conformational dynamics on the lipid composition. The peptide did not bind to lipids in the solid ordered phase and aggregated only in the liquid ordered "raft"-like bilayers. Self-association could not be detected in solution or in the presence of liquid disordered membranes. Surface-bound amphipathic SAP in a nonaggregated state was structured as a mixture of nonideal extended conformations reflecting the equilibrium already present in solution, i.e., before binding to the membrane.

Effects of carbohydrase enzyme supplementation on performance, eggshell quality, and bone parameters of laying hens fed on maize- and wheat-based diets.

PubMed

Olgun, Osman; Altay, Y; Yildiz, Alp O

2018-04-01

1. This study was conducted to determine the effects of enzyme supplementation of maize/wheat-based diets on the performance, egg quality, and serum and bone parameters of laying hens. 2. During the 12-week experimental period, a total of 72 laying hens aged 52 weeks were randomly distributed among 6 experimental groups. Each experimental group contained 4 replicates, each with three birds. The experiment was a randomised design consisting of a 3 × 2 factorial arrangement, with three levels of wheat substitution and two levels of enzyme (xylanase: 1500.00 U/kg, β-glucanase: 100 000 U/kg, cellulase: 1 000 000 U/kg, α-amylase: 160 000 U/kg) inclusion in the diet. Wheat replaced 0, 50, or 100% of maize with or without 1.0 g/kg enzyme supplementation in iso-nitrogenous and iso-caloric experimental diets. 3. Body weight, egg production, egg weight, egg mass, eggshell thickness, and the feed conversion ratio were adversely affected by the wheat-based diet. The eggshell quality parameters decreased with enzyme supplementation to the diet. 4. Wheat-based diets adversely affected calcium and phosphorus concentrations in the tibia, but the addition of the enzymes to the wheat-based diet prevented the negative effects of wheat-based diets on tibia mineralisation in laying hens. The wheat-based diets tended to reduce plasma mineral contents, and the addition of enzymes tended to affect plasma minerals and biomechanical properties of the tibia positively in laying hens. 5. These results indicate that wheat-based diets in aged laying hens adversely affected the mineral metabolism compared with maize-based diets, and the negative effects of wheat on bone mineralisation can be prevented by enzyme supplementation to the diets in laying hens.

Molecularly imprinted polymer (MIP) membrane assisted direct spray ionization mass spectrometry for agrochemicals screening in foodstuffs.

PubMed

Pereira, Igor; Rodrigues, Marcella Ferreira; Chaves, Andréa Rodrigues; Vaz, Boniek Gontijo

2018-02-01

Paper spray ionization (PSI) has some limitations such as low sensitivity and ionization suppression when complex samples are analyzed. The use of sample preparation devices directly coupled to MS can avoid these restrictions. Molecularly imprinted polymers (MIPs) are materials widely used as adsorbent in sample preparation methods such as solid-phase extraction and solid-phase microextraction, and they can provide specifics cavities with affinity to a target molecule. Here, we introduce a new MIP membrane spray ionization method combining MIP and PSI. MIP was synthesized directly on a cellulose membrane. Monuron and 2,4,5-T (2,4,5-trichlorophenoxyacetic acid) were used as template molecules in MIP synthesis for diuron and 2,4-D (2,4-dichlorophenoxyacetic acid) analyte sequesters, respectively. Apple, banana and grape methanolic extracts were used as matrices. The MIP membrane spray showed signal intensities of diuron and 2,4-D that were much higher compared to those obtained by non-imprinted polymers(NIP). Calibration curves exhibited R 2 > 0.99 for diuron and 2,4-D in all fruit extracts analyzed. LODs were found less than 0.60µgL -1 and LLOQs were found less than 2.00µgL -1 . The coefficients of variation and relative errors were less than 15% for almost all analyses. The apparent recovery test results ranged between 92,5% and 116.9%. Finally, the MIP membrane spray method was employed for the quantification of diuron and 2,4-D in real samples. Diuron contents were only found in three bananas (4.0, 6.5, and 9.9µgL -1 ). The proposed MIP membrane spray ionization method was straightforward, fast to carry out and provided satisfactory results for analyses of diuron and 2,4-D in apple, banana and grape samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of a glucose-triazole-hydrogenated cardanol conjugate on lipid bilayer membrane organization and thermotropic phase transition

NASA Astrophysics Data System (ADS)

Swain, Jitendriya; Kamalraj, M.; Surya Prakash Rao, H.; Mishra, Ashok K.

2015-02-01

This work focuses on the membrane perturbation, solubilisation and thermotropic phase transition process of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) MLVs induced by a glucose-triazole-hydrogenated cardanol conjugate (GTHCC). GTHCC is a recently introduced non toxic sugar derivative. Differential scanning calorimetry (DSC) and fluorescence molecular probe based techniques have been used to understand the concentration dependent membrane perturbation, solubilisation and thermotropic phase transition process of DPPC MLVs. The phase transition temperature of DPPC MLVs decreases with increase in mol% of GTHCC. At higher concentration above 10 mol%, GTHCC was significantly perturbed the membrane organization. The intrinsic fluorescence of GTHCC is also found to be sensitive towards phase behaviour and changes in membrane organization of DPPC MLVs.

Applications of solid-state NMR to membrane proteins.

PubMed

Ladizhansky, Vladimir

2017-11-01

Membrane proteins mediate flow of molecules, signals, and energy between cells and intracellular compartments. Understanding membrane protein function requires a detailed understanding of the structural and dynamic properties involved. Lipid bilayers provide a native-like environment for structure-function investigations of membrane proteins. In this review we give a general discourse on the recent progress in the field of solid-state NMR of membrane proteins. Solid-state NMR is a variation of NMR spectroscopy that is applicable to molecular systems with restricted mobility, such as high molecular weight proteins and protein complexes, supramolecular assemblies, or membrane proteins in a phospholipid environment. We highlight recent advances in applications of solid-state NMR to membrane proteins, specifically focusing on the recent developments in the field of Dynamic Nuclear Polarization, proton detection, and solid-state NMR applications in situ (in cell membranes). This article is part of a Special Issue entitled: Biophysics in Canada, edited by Lewis Kay, John Baenziger, Albert Berghuis and Peter Tieleman. Copyright © 2017 Elsevier B.V. All rights reserved.

Structure and Function Study of HIV and Influenza Fusion Proteins

NASA Astrophysics Data System (ADS)

Liang, Shuang

Human immunodeficiency virus (HIV) and influenza virus are membrane-enveloped viruses causing acquired immunodeficiency syndrome (AIDS) and flu. The initial step of HIV and influenza virus infection is fusion between viral and host cell membrane catalyzed by the viral fusion protein gp41 and hemagglutinin (HA) respectively. However, the structure of gp41 and HA as well as the infection mechanism are still not fully understood. This work addresses (1) full length gp41 ectodomain and TM domain structure and function and (2) IFP membrane location and IFP-membrane interaction. My studies of gp41 protein and IFP can provide better understanding of the membrane fusion mechanism and may aid development of anti-viral therapeutics and vaccine. The full length ectodomain and transmembrane domain of gp41 and shorter constructs were expressed, purified and solubilized at physiology conditions. The constructs adopt overall alpha helical structure in SDS and DPC detergents, and showed hyperthermostability with Tm > 90 °C. The oligomeric states of these proteins vary in different detergent buffer: predominant trimer for all constructs and some hexamer fraction for HM and HM_TM protein in SDS at pH 7.4; and mixtures of monomer, trimer, and higher-order oligomer protein in DPC at pH 4.0 and 7.4. Substantial protein-induced vesicle fusion was observed, including fusion of neutral vesicles at neutral pH, which are the conditions similar HIV/cell fusion. Vesicle fusion by a gp41 ectodomain construct has rarely been observed under these conditions, and is aided by inclusion of both the FP and TM, and by protein which is predominantly trimer rather than monomer. Current data was integrated with existing data, and a structural model was proposed. Secondary structure and conformation of IFP is a helix-turn-helix structure in membrane. However, there has been arguments about the IFP membrane location. 13C-2H REDOR solid-state NMR is used to solve this problem. The IFP adopts major alpha helical, minor beta strand secondary structure in PC/PG membrane. The alpha helical IFP's with respectively 13CO labeled Leu-2, Ala-7 and Gly-16 all show close contacts with the lipid acyl chain tail, suggesting IFP has strong interaction with the membrane. By screening the current IFP topology models, it either has a membrane-spanning confirmation, or it promotes lipid trail protrusion. IFP bounded lipid membrane structure was studied by paramagnetic relaxation enhancement (PRE) solid-state NMR to provide more information about the detailed IFP membrane location model. The T2 relaxation time and rate were measured for membrane with or without IFP and with or without Mn2+ . Based on the results, it is concluded that IFP does not promote lipid protrusion at both gel phase and liquid phase, which is evidenced by that the R2 difference with and without Mn2+ is smaller for IFP free membrane than IFP bounded membrane, meaning IFP does not induce a smaller average distance between lipid acyl chain and aqueous layer. By integrating these results, a IFP membrane spanning model was proposed, in which IFP N-terminal helix adopts a 45° angle with respect to membrane normal.

Increased alloimmunisation and transfusion reaction reporting in patients with solid-phase panreactivity.

PubMed

Olofson, Andrea M; Chandler, Rachael M; Marx-Wood, Cynthia R; Babcock, Craig A; Dunbar, Nancy M

2017-11-01

Automated solid-phase antibody screening uses red blood cell (RBC) membranes immobilised on polystyrene test wells to detect RBC specific antibodies. Despite its time-saving and labour-saving benefits, this method produces a higher rate of nonspecific reactivity compared with manual screening. Solid-phase panreactivity (SPP) is characterised by panreactivity (ie, all test cells reacting) in solid-phase testing accompanied by a negative autocontrol and a lack of reactivity when the same screening cells are tested in tube. The mechanisms underlying SPP and its clinical significance remain unclear. The goals of this study were to describe the prevalence of SPP at our institution and determine the alloimmunisation and transfusion reaction rates within this population. Data were collected on all patients undergoing type and screen testing over a 6-year period. Study patients undergoing subsequent transfusion were evaluated for reported transfusion reactions and development of new alloantibodies. Of the 76 051 patients studied, 0.7% demonstrated SPP of which 11% developed new alloantibodies. The transfusion reaction reporting rate among patients with SPP was 2%. Our data suggest that patients with SPP have higher rates of reported transfusion reactions and alloantibody development compared with those without SPP. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Aqueous two-phase partition applied to the isolation of plasma membranes and Golgi apparatus from cultured mammalian cells.

PubMed

Morré, D M; Morre, D J

2000-06-23

Partitioning in dextran-poly(ethylene)glycol (PEG) aqueous-aqueous phase systems represents a mature technology with many applications to separations of cells and to the preparation of membranes from mammalian cells. Most applications to membrane isolation and purification have focused on plasma membranes, plasma membrane domains and separation of right side-out and inside-out plasma membrane vesicles. The method exploits a combination of membrane properties, including charge and hydrophobicity. Purification is based upon differential distributions of the constituents in a sample between the two principal compartments of the two phases (upper and lower) and at the interface. The order of affinity of animal cell membranes for the upper phase is: endoplasmic reticulum

Aqueous two-phase partition applied to the isolation of plasma membranes and Golgi apparatus from cultured mammalian cells

NASA Technical Reports Server (NTRS)

Morre, D. M.; Morre, D. J.

2000-01-01

Partitioning in dextran-poly(ethylene)glycol (PEG) aqueous-aqueous phase systems represents a mature technology with many applications to separations of cells and to the preparation of membranes from mammalian cells. Most applications to membrane isolation and purification have focused on plasma membranes, plasma membrane domains and separation of right side-out and inside-out plasma membrane vesicles. The method exploits a combination of membrane properties, including charge and hydrophobicity. Purification is based upon differential distributions of the constituents in a sample between the two principal compartments of the two phases (upper and lower) and at the interface. The order of affinity of animal cell membranes for the upper phase is: endoplasmic reticulum

The Role of 4-Hydroxyphenylpyruvate Dioxygenase in Enhancement of Solid-Phase Electron Transfer by Shewanella oneidensis MR-1

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

Turick, Charles E.; Beliaev, Alex S.; Zakrajsek, Brian A.

2009-05-01

ABSTRACT - While mechanistic details of dissimilatory metal reduction are far from being understood, it is postulated that the electron transfer to solid metal oxides is mediated by outer membrane associated c-type cytochromes and electron shuttling compounds. This study focuses on the production of homogensitate in Shewanella oneidensis MR-1, an intermediate of the tyrosine degradation pathway, which is a precursor of a redox cycling metabolite, pyomelanin. We determined that two enzymes involved in this pathway, 4-hydroxyphenylpyruvate dioxygenase (4HPPD) and homogentisate 1,2-dioxygenase are responsible for homogentisate production and oxidation, respectively. Inhibition of 4-HPPD activity with the specific inhibitor sulcotrione ([2-(2- chloro-more » 4- methane sulfonylbenzoyl)-1,3-cyclohexanedione), and deletion of melA, a gene encoding 4-HPPD, resulted in no pyomelanin production by S. oneidensis MR-1. Conversely, deletion of hmgA, which encodes the putative homogentisate 1,2-dioxygenase, resulted in pyomelanin overproduction. The efficiency and rates at which MR-1 reduces hydrous ferric oxide were directly linked to the ability of mutant strains to produce pyomelanin. Electrochemical studies with whole cells demonstrated that pyomelanin substantially increases the formal potential (E°') of S. oneidensis MR-1. Based on our findings, environmental production of pyomelanin likely contributes to an increased solid-phase metal reduction capacity in S. oneidensis MR-1.« less

THE ROLE OF 4-HYDROXYPHENYLPYRUVATE DIOXYGENASE IN ENHANCEMENT OF SOLID-PHASE ELECTRON TRANSFER BY SHEWANELLA ONEIDENSIS MR-1

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

Turick, C; Amy Ekechukwu, A

2007-06-01

While mechanistic details of dissimilatory metal reduction are far from being understood, it is postulated that the electron transfer to solid metal oxides is mediated by outer membrane-associated c-type cytochromes and redox active electron shuttling compounds. This study focuses on the production of homogensitate in Shewanella oneidensis MR-1, an intermediate of tyrosine degradation pathway, which is a precursor of a redox cycling metabolite, pyomelanin. In this study, we determined that two enzymes involved in this pathway, 4-hydroxyphenylpyruvate dioxygenase (4HPPD) and homogentisate 1,2-dioxygenase are responsible for homogentisate production and oxidation, respectively. Inhibition of 4-HPPD activity with the specific inhibitor sulcotrione (2-(2-chloro-4-methanemore » sulfonylbenzoyl)-1,3-cyclohexanedione), and deletion of melA, a gene encoding 4-HPPD, resulted in no pyomelanin production by S. oneidensis MR-1. Conversely, deletion of hmgA which encodes the putative homogentisate 1,2-dioxygenase, resulted in pyomelanin overproduction. The efficiency and rates, with which MR-1 reduces hydrous ferric oxide, were directly linked to the ability of mutant strains to produce pyomelanin. Electrochemical studies with whole cells demonstrated that pyomelanin substantially increases the formal potential (E{sup o}{prime}) of S. oneidensis MR-1. Based on this work, environmental production of pyomelanin likely contributes to an increased solid-phase metal reduction capacity in Shewanella oneidensis.« less

Recent Application of Solid Phase Based Techniques for Extraction and Preconcentration of Cyanotoxins in Environmental Matrices.

PubMed

Mashile, Geaneth Pertunia; Nomngongo, Philiswa N

2017-03-04

Cyanotoxins are toxic and are found in eutrophic, municipal, and residential water supplies. For this reason, their occurrence in drinking water systems has become a global concern. Therefore, monitoring, control, risk assessment, and prevention of these contaminants in the environmental bodies are important subjects associated with public health. Thus, rapid, sensitive, selective, simple, and accurate analytical methods for the identification and determination of cyanotoxins are required. In this paper, the sampling methodologies and applications of solid phase-based sample preparation methods for the determination of cyanotoxins in environmental matrices are reviewed. The sample preparation techniques mainly include solid phase micro-extraction (SPME), solid phase extraction (SPE), and solid phase adsorption toxin tracking technology (SPATT). In addition, advantages and disadvantages and future prospects of these methods have been discussed.

Quick, easy, cheap, effective, rugged, and safe sample preparation approach for pesticide residue analysis using traditional detectors in chromatography: A review.

PubMed

Rahman, Md Musfiqur; Abd El-Aty, A M; Kim, Sung-Woo; Shin, Sung Chul; Shin, Ho-Chul; Shim, Jae-Han

2017-01-01

In pesticide residue analysis, relatively low-sensitivity traditional detectors, such as UV, diode array, electron-capture, flame photometric, and nitrogen-phosphorus detectors, have been used following classical sample preparation (liquid-liquid extraction and open glass column cleanup); however, the extraction method is laborious, time-consuming, and requires large volumes of toxic organic solvents. A quick, easy, cheap, effective, rugged, and safe method was introduced in 2003 and coupled with selective and sensitive mass detectors to overcome the aforementioned drawbacks. Compared to traditional detectors, mass spectrometers are still far more expensive and not available in most modestly equipped laboratories, owing to maintenance and cost-related issues. Even available, traditional detectors are still being used for analysis of residues in agricultural commodities. It is widely known that the quick, easy, cheap, effective, rugged, and safe method is incompatible with conventional detectors owing to matrix complexity and low sensitivity. Therefore, modifications using column/cartridge-based solid-phase extraction instead of dispersive solid-phase extraction for cleanup have been applied in most cases to compensate and enable the adaptation of the extraction method to conventional detectors. In gas chromatography, the matrix enhancement effect of some analytes has been observed, which lowers the limit of detection and, therefore, enables gas chromatography to be compatible with the quick, easy, cheap, effective, rugged, and safe extraction method. For liquid chromatography with a UV detector, a combination of column/cartridge-based solid-phase extraction and dispersive solid-phase extraction was found to reduce the matrix interference and increase the sensitivity. A suitable double-layer column/cartridge-based solid-phase extraction might be the perfect solution, instead of a time-consuming combination of column/cartridge-based solid-phase extraction and dispersive solid-phase extraction. Therefore, replacing dispersive solid-phase extraction with column/cartridge-based solid-phase extraction in the cleanup step can make the quick, easy, cheap, effective, rugged, and safe extraction method compatible with traditional detectors for more sensitive, effective, and green analysis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Magnesium Recycling of Partially Oxidized, Mixed Magnesium-Aluminum Scrap through Combined Refining and Solid Oxide Membrane Electrolysis Processes

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

Xiaofei Guan; Peter A. Zink; Uday B. Pal

2012-01-01

Pure magnesium (Mg) is recycled from 19g of partially oxidized 50.5wt.% Mg-Aluminum (Al) alloy. During the refining process, potentiodynamic scans (PDS) were performed to determine the electrorefining potential for magnesium. The PDS show that the electrorefining potential increases over time as the magnesium content inside the Mg-Al scrap decreases. Up to 100% percent of magnesium is refined from the Mg-Al scrap by a novel refining process of dissolving magnesium and its oxide into a flux followed by vapor phase removal of dissolved magnesium and subsequently condensing the magnesium vapor. The solid oxide membrane (SOM) electrolysis process is employed in themore » refining system to enable additional recycling of magnesium from magnesium oxide (MgO) in the partially oxidized Mg-Al scrap. The combination of the refining and SOM processes yields 7.4g of pure magnesium.« less

Solid-state membrane module

DOEpatents

Gordon, John Howard [Salt Lake City, UT; Taylor, Dale M [Murray, UT

2011-06-07

Solid-state membrane modules comprising at least one membrane unit, where the membrane unit has a dense mixed conducting oxide layer, and at least one conduit or manifold wherein the conduit or manifold comprises a dense layer and at least one of a porous layer and a slotted layer contiguous with the dense layer. The solid-state membrane modules may be used to carry out a variety of processes including the separating of any ionizable component from a feedstream wherein such ionizable component is capable of being transported through a dense mixed conducting oxide layer of the membrane units making up the membrane modules. For ease of construction, the membrane units may be planar.

Profile structures of the voltage-sensor domain and the voltage-gated K+-channel vectorially oriented in a single phospholipid bilayer membrane at the solid-vapor and solid-liquid interfaces determined by x-ray interferometry

PubMed Central

Gupta, S.; Liu, J.; Strzalka, J.; Blasie, J. K.

2011-01-01

One subunit of the prokaryotic voltage-gated potassium ion channel from Aeropyrum pernix (KvAP) is comprised of six transmembrane α helices, of which S1–S4 form the voltage-sensor domain (VSD) and S5 and S6 contribute to the pore domain (PD) of the functional homotetramer. However, the mechanism of electromechanical coupling interconverting the closed-to-open (i.e., nonconducting-to-K+-conducting) states remains undetermined. Here, we have vectorially oriented the detergent (OG)-solubilized VSD in single monolayers by two independent approaches, namely “directed-assembly” and “self-assembly,” to achieve a high in-plane density. Both utilize Ni coordination chemistry to tether the protein to an alkylated inorganic surface via its C-terminal His6 tag. Subsequently, the detergent is replaced by phospholipid (POPC) via exchange, intended to reconstitute a phospholipid bilayer environment for the protein. X-ray interferometry, in which interference with a multilayer reference structure is used to both enhance and phase the specular x-ray reflectivity from the tethered single membrane, was used to determine directly the electron density profile structures of the VSD protein solvated by detergent versus phospholipid, and with either a moist He (moderate hydration) or bulk aqueous buffer (high hydration) environment to preserve a native structure conformation. Difference electron density profiles, with respect to the multilayer substrate itself, for the VSD-OG monolayer and VSD-POPC membranes at both the solid-vapor and solid-liquid interfaces, reveal the profile structures of the VSD protein dominating these profiles and further indicate a successful reconstitution of a lipid bilayer environment. The self-assembly approach was similarly extended to the intact full-length KvAP channel for comparison. The spatial extent and asymmetry in the profile structures of both proteins confirm their unidirectional vectorial orientation within the reconstituted membrane and indicate retention of the protein’s folded three-dimensional tertiary structure upon completion of membrane bilayer reconstitution. Moreover, the resulting high in-plane density of vectorially oriented protein within a fully hydrated single phospholipid bilayer membrane at the solid-liquid interface will enable investigation of their conformational states as a function of the transmembrane electric potential. PMID:22060407

FOST 2 Upgrade with Hollow-Fiber CTA FO Module and Generation of Osmotic Agent for Microorganism Growth Studies

NASA Technical Reports Server (NTRS)

Parodi, Jurek; Mangado, Jaione Romero; Stefanson, Ofir; Flynn, Michael; Shaw, Hali; Beeler, David

2016-01-01

FOST 2 is an integrated membrane system that incorporates a forward osmosis subsystem and a reverse osmosis subsystem working in series. It has been designed as a post treatment system to process the effluent from the Membrane Aerated Biological Reactor developed at NASA Johnson Space Center and Texas Tech University. Its function is to remove dissolved solids residual such as ammonia and suspended solids, as well as to provide a physical barrier to microbial and viral contamination. A tubular CTA membrane module from HTI and a flat-sheet lipid-base membrane module from Porifera were integrated and tested on FOST 2 in the past, using both a bioreactor's effluent and greywater as the feed solution. This paper documents the performance of FOST 2 after its upgrade with a hollow-fiber CTA membrane module from Toyobo, treating real black-water to generate the osmotic agent solution necessary to conduct growth studies of genetically engineered microorganism for the Synthetic Biological Membrane project.

Monitoring Membrane Hydration with 2-(Dimethylamino)-6-Acylnaphtalenes Fluorescent Probes.

PubMed

Bagatolli, Luis A

2015-01-01

A family of polarity sensitive fluorescent probes (2-(dimethylamino)-6-acylnaphtalenes, i.e. LAURDAN, PRODAN, ACDAN) was introduced by Gregorio Weber in 1979, with the aim to monitor solvent relaxation phenomena on protein matrices. In the following years, however, PRODAN and particularly LAURDAN, were used to study membrane lateral structure and associated dynamics. Once incorporated into membranes, the (nanosecond) fluorescent decay of these probes is strongly affected by changes in the local polarity and relaxation dynamics of restricted water molecules existing at the membrane/water interface. For instance, when glycerophospholipid containing membranes undertake a solid ordered (gel) to liquid disordered phase transition the fluorescence emission maximum of these probes shift ~ 50 nm with a significant change in their fluorescence lifetime. Furthermore, the fluorescence parameters of LAURDAN and PRODAN are exquisitely sensitive to cholesterol effects, allowing interpretations that correlate changes in membrane packing with membrane hydration. Different membrane model systems as well as innate biological membranes have been studied with this family of probes allowing interesting comparative studies. This chapter presents a short historical overview about these fluorescent reporters, discusses on different models proposed to explain their sensitivity to membrane hydration, and includes relevant examples from experiments performed in artificial and biological membranes.

A Simple, Cost-Efficient Method to Separate Microalgal Lipids from Wet Biomass Using Surface Energy-Modified Membranes.

PubMed

Kwak, Moo Jin; Yoo, Youngmin; Lee, Han Sol; Kim, Jiyeon; Yang, Ji-Won; Han, Jong-In; Im, Sung Gap; Kwon, Jong-Hee

2016-01-13

For the efficient separation of lipid extracted from microalgae cells, a novel membrane was devised by introducing a functional polymer coating onto a membrane surface by means of an initiated chemical vapor deposition (iCVD) process. To this end, a steel-use-stainless (SUS) membrane was modified in a way that its surface energy was systemically modified. The surface modification by conformal coating of functional polymer film allowed for selective separation of oil-water mixture, by harnessing the tuned interfacial energy between each liquid phase and the membrane surface. The surface-modified membrane, when used with chloroform-based solvent, exhibited superb permeate flux, breakthrough pressure, and also separation yield: it allowed separation of 95.5 ± 1.2% of converted lipid (FAME) in the chloroform phase from the water/MeOH phase with microalgal debris. This result clearly supported that the membrane-based lipid separation is indeed facilitated by way of membrane being functionalized, enabling us to simplify the whole downstream process of microalgae-derived biodiesel production.

Manual Solid-Phase Peptide Synthesis of Metallocene-Peptide Bioconjugates

ERIC Educational Resources Information Center

Kirin, Srecko I.; Noor, Fozia; Metzler-Nolte, Nils; Mier, Walter

2007-01-01

A simple and relatively inexpensive procedure for preparing a biologically active peptide using solid phase peptide synthesis (SPPS) is described. Fourth-year undergraduate students have gained firsthand experience from the solid-phase synthesis techniques and they have become familiar with modern analytical techniques based on the particular…

Crocodilian Nest in a Late Cretaceous Sauropod Hatchery from the Type Lameta Ghat Locality, Jabalpur, India

PubMed Central

Srivastava, Rahul; Patnaik, Rajeev; Shukla, U. K.; Sahni, Ashok

2015-01-01

The well-known Late Cretaceous Lameta Ghat locality (Jabalpur, India) provides a window of opportunity to study a large stable, near shore sandy beach, which was widely used by sauropod dinosaurs as a hatchery. In this paper, we revisit the eggs and eggshell fragments previously assigned to lizards from this locality and reassign them to crocodylomorphs. Several features point to a crocodilian affinity, including a subspherical to ellipsoidal shape, smooth, uneven external surface, discrete trapezoid shaped shell units with wide top and narrow base, basal knobs and wedge shaped crystallites showing typical inverted triangular extinction under crossed nicols. The crocodylomorph eggshell material presented in this paper adds to the skeletal data of these most probably Cretaceous-Eocene dryosaurid crocodiles. PMID:26641665

Cyclic and Linear Monoterpenes in Phospholipid Membranes: Phase Behavior, Bilayer Structure, and Molecular Dynamics.

PubMed

Pham, Quoc Dat; Topgaard, Daniel; Sparr, Emma

2015-10-13

Monoterpenes are abundant in essential oils extracted from plants. These relatively small and hydrophobic molecules have shown important biological functions, including antimicrobial activity and membrane penetration enhancement. The interaction between the monoterpenes and lipid bilayers is considered important to the understanding of the biological functions of monoterpenes. In this study, we investigated the effect of cyclic and linear monoterpenes on the structure and dynamics of lipids in model membranes. We have studied the ternary system 1,2-dimyristoyl-sn-glycero-3-phosphocholine-monoterpene-water as a model with a focus on dehydrated conditions. By combining complementary techniques, including differential scanning calorimetry, solid-state nuclear magnetic resonance, and small- and wide-angle X-ray scattering, bilayer structure, phase transitions, and lipid molecular dynamics were investigated at different water contents. Monoterpenes cause pronounced melting point depression and phase segregation in lipid bilayers, and the extent of these effects depends on the hydration conditions. The addition of a small amount of thymol to the fluid bilayer (volume fraction of 0.03 in the bilayer) leads to an increased order in the acyl chain close to the bilayer interface. The findings are discussed in relation to biological systems and lipid formulations.

Ca-doped LTO using waste eggshells as Ca source to improve the discharge capacity of anode material for lithium-ion battery

NASA Astrophysics Data System (ADS)

Setiawan, D.; Subhan, A.; Saptari, S. A.

2017-07-01

The necessity of high charge-discharge capacity lithium-ion battery becomes very urgent due to its applications demand. Several researches have been done to meet the demand including Ca doping on Li4Ti5O12 for anode material of lithium-ion batteries. Ca-doped Li4Ti5O12 (LTO) in the form of Li4-xCaxTi5O12 (x = 0, 0.05, 0.075, and 0.1) have been synthesized using simple solid state reaction. The materials preparation involved waste eggshells in the form of CaCO3 as Ca source. The structure and capacity of as-prepared samples were characterized using X-Ray Diffractometer and Cyclic Voltametry. X-Ray Diffractometer characterization revealed that all amount of dopant had entered the lattice structure of LTO successfully. The crystalline sizes were obtained by using Scherrer equation. No significant differences are detected in lattice parameters (˜8.35 Å) and crystalline sizes (˜27 nm) between all samples. Cyclic Voltametry characterization shows that Li4-xCaxTi5O12 (x = 0.05) has highest charge-discharge capacity of 177.14 mAh/g and 181.92 mAh/g, respectively. Redox-potentials of samples show no significant differences with the average of 1.589 V.

Egg Speckling Patterns Do Not Advertise Offspring Quality or Influence Male Provisioning in Great Tits

PubMed Central

Stoddard, Mary Caswell; Fayet, Annette L.; Kilner, Rebecca M.; Hinde, Camilla A.

2012-01-01

Many passerine birds lay white eggs with reddish brown speckles produced by protoporphyrin pigment. However, the function of these spots is contested. Recently, the sexually selected eggshell coloration (SSEC) hypothesis proposed that eggshell color is a sexually selected signal through which a female advertises her quality (and hence the potential quality of her future young) to her male partner, thereby encouraging him to contribute more to breeding attempts. We performed a test of the SSEC hypothesis in a common passerine, the great tit Parus major. We used a double cross-fostering design to determine whether males change their provisioning behavior based on eggshell patterns they observe at the nest. We also tested the assumption that egg patterning reflects female and/or offspring quality. Because birds differ from humans in their color and pattern perception, we used digital photography and models of bird vision to quantify egg patterns objectively. Neither male provisioning nor chick growth was related to the pattern of eggs males observed during incubation. Although heavy females laid paler, less speckled eggs, these eggs did not produce chicks that grew faster. Therefore, we conclude that the SSEC hypothesis is an unlikely explanation for the evolution of egg speckling in great tits. PMID:22815730

A stable perovskite electrolyte in moist air for Li-ion batteries.

PubMed

Li, Yutao; Xu, Henghui; Chien, Po-Hsiu; Wu, Nan; Xin, Sen; Xue, Leigang; Park, Kyusung; Hu, Yan-Yan; Goodenough, John B

2018-05-07

Solid-oxide Li+ electrolytes of a rechargeable cell are generally sensitive to moisture in the air, H+ exchanges for the mobile Li+ of the electrolyte and forms insulating surface phases at the electrolyte interfaces and in the grain boundaries of a polycrystalline membrane. These surface phases dominate the total interfacial resistance of a conventional rechargeable cell having a solid-electrolyte separator. We report a new perovskite Li+ solid electrolyte, Li0.38Sr0.44Ta0.7Hf0.3O2.95F0.05, having a Li-ion conductivity σLi = 4.8×10-4 S cm-1 at 25 oC that does not react with water having 3≤pH≤14. The solid electrolyte with a thin Li+-conducting polymer on its surface to prevent reduction of Ta5+ is wet by metallic lithium and provides low-impedance dendrite-free plating/stripping of a lithium anode. It is also stable on contact with a composite polymer cathode. With this solid electrolyte, we demonstrate excellent cycling performance of an all-solid-state Li/LiFePO4 cell, a Li-S cell with a polymer-gel cathode, and a supercapacitor. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Theoretical voltammetric response of electrodes coated by solid polymer electrolyte membranes.

PubMed

Gómez-Marín, Ana M; Hernández-Ortíz, Juan P

2014-09-24

A model for the differential capacitance of metal electrodes coated by solid polymer electrolyte membranes, with acid/base groups attached to the membrane backbone, and in contact with an electrolyte solution is developed. With proper model parameters, the model is able to predict a limit response, given by Mott-Schottky or Gouy-Chapman-Stern theories depending on the dissociation degree and the density of ionizable acid/base groups. The model is also valid for other ionic membranes with proton donor/acceptor molecules as membrane counterions. Results are discussed in light of the electron transfer rate at membrane-coated electrodes for electrochemical reactions that strongly depend on the double layer structure. In this sense, the model provides a tool towards the understanding of the electro-catalytic activity on modified electrodes. It is shown that local maxima and minima in the differential capacitance as a function of the electrode potential may occur as consequence of the dissociation of acid/base molecular species, in absence of specific adsorption of immobile polymer anions on the electrode surface. Although the model extends the conceptual framework for the interpretation of cyclic voltammograms for these systems and the general theory about electrified interfaces, structural features of real systems are more complex and so, presented results only are qualitatively compared with experiments. Copyright © 2014 Elsevier B.V. All rights reserved.

Speckled eggs: water-loss and incubation behaviour in the great tit Parus major.

PubMed

Higham, James P; Gosler, Andrew G

2006-10-01

Many small passerine birds worldwide lay white eggs speckled with red, brown and black protoporphyrin pigment spots (maculation). Unlike some patterns of avian eggshell pigmentation which clearly serve a crypsis or signalling function, the ubiquity of maculation among passerines suggests that its origins lie in another function, not specific to any particular ecological or behavioural group. Elsewhere, we have presented evidence that protoporphyrin pigments serve a structural function related to eggshell thickness and calcium availability: eggshell maculation in the great tit Parus major increases with decreasing soil calcium levels, pigments demarcate thinner areas of shell, and both the pigment intensity and distribution are related to shell thickness. Here we show that maculation also affects the rate of water loss from the egg during incubation (approximately Mass Loss per Day or MLD, which is critical to egg viability), but not that of unincubated eggs. We also demonstrate, both by observation and experiment, that the effect of female incubation behaviour on MLD compensates in some way for variation in egg characteristics, and that differences between females in the degree of such compensation are related to differences in clutch maculation. Our results suggest that, while a principal function of maculation in this species may be to strengthen the eggshell, it may also reduce eggshell permeability when large amounts of pigment are used, and that this necessitates a behavioural adjustment from the female during incubation. We discuss these findings and make further testable predictions from our model.

Residues of chromium, nickel, cadmium and lead in Rook Corvus frugilegus eggshells from urban and rural areas of Poland.

PubMed

Orłowski, Grzegorz; Kasprzykowski, Zbigniew; Dobicki, Wojciech; Pokorny, Przemysław; Wuczyński, Andrzej; Polechoński, Ryszard; Mazgajski, Tomasz D

2014-08-15

We examined the concentrations of chromium (Cr), nickel (Ni), cadmium (Cd) and lead (Pb) in Rook Corvus frugilegus eggshells from 43 rookeries situated in rural and urban areas of western (=intensive agriculture) and eastern (=extensive agriculture) Poland. We found small ranges in the overall level of Cr (the difference between the extreme values was 1.8-fold; range of concentrations=5.21-9.40 Cr ppm), Ni (3.5-fold; 1.15-4.07 Ni ppm), and Cd (2.6-fold; 0.34-0.91 Cd ppm), whereas concentrations of Pb varied markedly, i.e. 6.7-fold between extreme values (1.71-11.53 Pb ppm). Eggshell levels of these four elements did not differ between rural rookeries from western and eastern Poland, but eggshells from rookeries in large/industrial cities had significantly higher concentrations of Cr, Ni and Pb than those from small towns and villages. Our study suggests that female Rooks exhibited an apparent variation in the intensity of trace metal bioaccumulation in their eggshells, that rapid site-dependent bioaccumulation of Cu, Cr, Ni and Pb occurs as a result of the pollution gradient (rural

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

Hu, Michael Z.; Engtrakul, Chaiwat; Bischoff, Brian L.

A new class of inorganic-based membranes, i.e., High-Performance Architectured Surface Selective (HiPAS) membranes, is introduced to provide high perm-selective flux by exploiting unique separation mechanisms induced by superhydrophobic or superhydrophilic surface interactions and confined capillary condensation in enlarged membrane pores (~8 nm). The super-hydro-tunable HiPAS membranes were originally developed for the purpose of bio-oil/biofuel processing to achieve selective separations at higher flux relative to size selective porous membranes (e.g., inorganic zeolite-based membranes) and better high-temperature tolerance than polymer membranes (>250 C) for hot vapor processing. Due to surface-enhanced separation selectivity, HiPAS membranes can thus possibly enable larger pores to facilitatemore » large-flux separations by increasing from sub-nanometer pores to mesopores (2-50 nm) for vapor phase or micron-scale pores for liquid phase separations. In this paper, we describe an innovative membrane concept and a materials synthesis strategy to fabricate HiPAS membranes, and demonstrate selective permeation in both vapor- and liquid-phase applications. High permeability and selectivity were demonstrated using surrogate mixtures, such as ethanol-water, toluene-water, and toluene-phenol-water. The overall membrane evaluation results show promise for the future processing of biomass pyrolysis and upgraded product vapors and condensed liquid bio-oil intermediates.« less

Bioefficacy comparison of organic manganese with inorganic manganese for eggshell quality in Hy-Line Brown laying hens.

PubMed

Xiao, J F; Wu, S G; Zhang, H J; Yue, H Y; Wang, J; Ji, F; Qi, G H

2015-08-01

This study was aimed at investigating the bioefficacy of organic compared with inorganic manganese (Mn) for eggshell quality. An amino acid-Mn complex or Mn sulfate monohydrate was used as the organic or inorganic Mn source. A total of six hundred forty-eight 50-wk-old layers (Hy-Line Brown) were divided into 9 groups; each group consisted of 6 replicates with 12 layers each. The feeding trial lasted 12 wk. During the first 4 wk of the feeding trial, the groups were fed a basal diet, which met the nutrient requirements of the layers, except for Mn. During the following 8 wk, 9 levels of Mn (inorganic Mn: 0, 25, 50, 100, and 200 mg/kg; organic Mn: 25, 50, 100, and 200 mg/kg) were used to supplement, respectively, in the basal diet on an equimolar basis. An exponential regression model was applied to calculate the bioefficacy of organic Mn compared with the inorganic Mn. Dietary supplementation with either organic or inorganic Mn did not influence egg production and feed efficiency of (P > 0.05), and eggshell quality did not exhibit a significant response to dietary supplementation with Mn sources at 56 and 58 wk (P > 0.05). Dietary supplementation with either organic Mn or inorganic Mn significantly enhanced the thickness, breaking strength, and elastic modulus of the eggshells compared with the control group at the end of 62 wk (P < 0.05). At the end of 62 wk, the bioefficacy of organic Mn was 357% (shell thickness), 406% (breaking strength), 458% (elastic modulus), and 470% (eggshell Mn), as efficacious as inorganic Mn at equimolar levels. This study suggests that organic Mn enhances eggshell quality in aged laying hens compared with inorganic Mn. © 2015 Poultry Science Association Inc.

Microbial abundance on the eggs of a passerine bird and related fitness consequences between urban and rural habitats

PubMed Central

Lee, Sang-im; Lee, Hyunna; Jablonski, Piotr G.; Choe, Jae Chun

2017-01-01

Urban environments present novel and challenging habitats to wildlife. In addition to well-known difference in abiotic factors between rural and urban environments, the biotic environment, including microbial fauna, may also differ significantly. In this study, we aimed to compare the change in microbial abundance on eggshells during incubation between urban and rural populations of a passerine bird, the Eurasian Magpie (Pica pica), and examine the consequences of any differences in microbial abundances in terms of hatching success and nestling survival. Using real-time PCR, we quantified the abundances of total bacteria, Escherichia coli/Shigella spp., surfactin-producing Bacillus spp. and Candida albicans on the eggshells of magpies. We found that urban magpie eggs harboured greater abundances of E. coli/Shigella spp. and C. albicans before incubation than rural magpie eggs. During incubation, there was an increase in the total bacterial load, but a decrease in C. albicans on urban eggs relative to rural eggs. Rural eggs showed a greater increase in E. coli/Shigella spp. relative to their urban counterpart. Hatching success of the brood was generally lower in urban than rural population. Nestling survival was differentially related with the eggshell microbial abundance between urban and rural populations, which was speculated to be the result of the difference in the strength of the interaction among the microbes. This is the first demonstration that avian clutches in urban and rural populations differ in eggshell microbial abundance, which can be further related to the difference in hatching success and nestling survival in these two types of environments. We suggest that future studies on the eggshell microbes should investigate the interaction among the microbes, because the incubation and/or environmental factors such as urbanization or climate condition can influence the dynamic interactions among the microbes on the eggshells which can further determine the breeding success of the parents. PMID:28953940

Productive performance, eggshell quality, and eggshell ultrastructure of laying hens fed diets supplemented with organic trace minerals.

PubMed

Stefanello, C; Santos, T C; Murakami, A E; Martins, E N; Carneiro, T C

2014-01-01

This study was carried out with the purpose of evaluating the effect of supplementing hens' diets with trace minerals from inorganic or organic sources on the productive performance, eggshell quality, and eggshell ultrastructure of laying hens. Three hundred sixty Hy-Line W36 laying hens between 47 to 62 wk of age were used and distributed in a completely randomized experimental design with 9 treatments, 5 replicates, and 8 birds for each experimental unit. The treatments consisted of a control diet without supplementation of the trace minerals Mn, Zn, and Cu; 4 supplementation levels of these trace minerals from an inorganic source; and the same levels of supplementation from an organic source (proteinates). The supplementation levels in milligrams per kilogram for Mn, Zn, and Cu, were, respectively, 35-30-05, 65-60-10, 95-90-15, and 125-120-20. There was no effect of supplementation of trace minerals on the rate of posture, feed intake, feed conversion, specific weight, and Haugh unit of eggs. However, there was a quadratic effect (P < 0.05) of the levels of trace mineral supplementation on average egg weight and egg mass; the results did not differ regarding the source used. The increase in the levels of supplementation of Mn, Zn, and Cu provided a linear increase (P < 0.05) in the breaking strength and the percentage of eggshell. There was a linear decrease (P < 0.05) in the egg loss and the number of mammillary buttons in the shell. The best results were obtained using diets supplemented with trace minerals from an organic source because these diets provided lower egg loss, higher thickness, and increased strength of the shell. Structurally, organic Mn, Zn, and Cu provided higher thickness of the palisade layer and lower mammillary density. The trace mineral supplementation improved the structural characteristics and the quality of the eggshells.

Comparison of protoporphyrin IX content and related gene expression in the tissues of chickens laying brown-shelled eggs.

PubMed

Li, Guangqi; Chen, Sirui; Duan, Zhongyi; Qu, Lujiang; Xu, Guiyun; Yang, Ning

2013-12-01

Protoporphyrin IX (PpIX), an immediate precursor of heme, is the main pigment resulting in the brown coloration of eggshell. The brownness and uniformity of the eggshell are important marketing considerations. In this study, 9 chickens laying darker brown shelled eggs and 9 chickens laying lighter brown shelled eggs were selected from 464 individually caged layers in a Rhode Island Red pureline. The PpIX contents were measured with a Microplate Reader at the wavelength of 412 nm and were compared in different tissues of the 2 groups. Although no significant difference in serum, bile, and excreta was found between the 2 groups, PpIX content in the shell gland and eggshell of the darker group was higher than in those of the lighter group, suggesting that PpIX was synthesized in the shell gland. We further determined the expression levels of 8 genes encoding enzymes involved in the heme synthesis and transport in the liver and shell gland at 6 h postoviposition by quantitative PCR. The results showed that expression of aminolevulinic acid synthase-1 (ALAS1) was higher in the liver of hens laying darker brown shelled eggs, whereas in the shell gland the expression levels of ALAS1, coproporphyrinogen oxidase (CPOX), ATP-binding cassette family members ABCB7 and ABCG2, and receptor for feline leukemia virus, subgroup C (FLVCR) were significantly higher in the hens laying darker brown shelled eggs. Our results demonstrated that hens laying darker brown shelled eggs could deposit more PpIX onto the eggshell and the brownness of the eggshell was dependent on the total quantity of PpIX in the eggshell. More heme was synthesized in the liver and shell gland of hens laying darker brown shelled eggs than those of hens laying lighter brown shelled eggs. High expression level of ABCG2 might facilitate the accumulation of PpIX in the shell gland.

Microbial abundance on the eggs of a passerine bird and related fitness consequences between urban and rural habitats.

PubMed

Lee, Sang-Im; Lee, Hyunna; Jablonski, Piotr G; Choe, Jae Chun; Husby, Magne

2017-01-01

Urban environments present novel and challenging habitats to wildlife. In addition to well-known difference in abiotic factors between rural and urban environments, the biotic environment, including microbial fauna, may also differ significantly. In this study, we aimed to compare the change in microbial abundance on eggshells during incubation between urban and rural populations of a passerine bird, the Eurasian Magpie (Pica pica), and examine the consequences of any differences in microbial abundances in terms of hatching success and nestling survival. Using real-time PCR, we quantified the abundances of total bacteria, Escherichia coli/Shigella spp., surfactin-producing Bacillus spp. and Candida albicans on the eggshells of magpies. We found that urban magpie eggs harboured greater abundances of E. coli/Shigella spp. and C. albicans before incubation than rural magpie eggs. During incubation, there was an increase in the total bacterial load, but a decrease in C. albicans on urban eggs relative to rural eggs. Rural eggs showed a greater increase in E. coli/Shigella spp. relative to their urban counterpart. Hatching success of the brood was generally lower in urban than rural population. Nestling survival was differentially related with the eggshell microbial abundance between urban and rural populations, which was speculated to be the result of the difference in the strength of the interaction among the microbes. This is the first demonstration that avian clutches in urban and rural populations differ in eggshell microbial abundance, which can be further related to the difference in hatching success and nestling survival in these two types of environments. We suggest that future studies on the eggshell microbes should investigate the interaction among the microbes, because the incubation and/or environmental factors such as urbanization or climate condition can influence the dynamic interactions among the microbes on the eggshells which can further determine the breeding success of the parents.

Encapsulated Solid-Liquid Phase Change Nanoparticles as Thermal Barcodes for Highly Sensitive Detections of Multiple Lung Cancer Biomarkers

DTIC Science & Technology

2012-10-01

5e. TASK NUMBER LC90061 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT...transduction mechanism based on solid- liquid phase change nanoparticles works for the detection of multiple proteins. A series of metal and alloy...early stage. With the support from DOD-LCRP, we have proved the new signal transduction mechanism based on solid-liquid phase change nanoparticles works

Confocal reflectance quantitative phase microscope system for cellular membranes dynamics study (Conference Presentation)

NASA Astrophysics Data System (ADS)

Singh, Vijay Raj; Yaqoob, Zahid; So, Peter T. C.

2017-02-01

Quantitative phase microscopy (QPM) techniques developed so far primarily belongs to high speed transmitted light based systems that has enough sensitivity to resolve membrane fluctuations and dynamics, but has no depth resolution. Therefore, most biomechanics studies using QPM today is confined to simple cells, such as RBCs, without internal organelles. An important instrument that will greatly extend the biomedical applications of QPM is to develop next generation microscope with 3D capability and sufficient temporal resolution to study biomechanics of complex eukaryotic cells including the mechanics of their internal compartments. For eukaryotic cells, the depth sectioning capability is critical and should be sufficient to distinguish nucleic membrane fluctuations from plasma membrane fluctuations. Further, this microscope must provide high temporal resolution since typical eukaryotes membranes are substantially stiffer than RBCs. A confocal reflectance quantitative phase microscope is presented based on multi-pinhole scanning, with the capabilities of higher temporal resolution and sensitivity for nucleic and plasma membranes of eukaryotic cells. System hardware is developed based on an array of confocal pinhole generated by using the `ON' state of subset of micro-mirrors of digital micro-mirror device (DMD, from Texas Instruments) and high-speed raster scanning provides 14ms imaging speed in wide-field mode. A common path interferometer is integrated at the imaging arm for detection of specimens' quantitative phase information. Theoretical investigation of quantitative phase reconstructed from system is investigated and application of system is presented for dimensional fluctuations measurements of both cellular plasma and nucleic membranes of embryonic stem cells.

Determination of perfluorinated carboxylic acids in fish fillet by micro-solid phase extraction, followed by liquid chromatography-triple quadrupole mass spectrometry.

PubMed

Lashgari, Maryam; Lee, Hian Kee

2014-11-21

In the current study, a simple, fast and efficient combination of protein precipitation and micro-solid phase extraction (μ-SPE) followed by liquid chromatography-triple quadrupole tandem mass spectrometry (LC-MS/MS) was developed for the determination of perfluorinated carboxylic acids (PFCAs) in fish fillet. Ten PFCAs with different hydrocarbon chain lengths (C5-C14) were analysed simultaneously using this method. Protein precipitation by acetonitrile and μ-SPE by surfactant-incorporated ordered mesoporous silica were applied to the extraction and concentration of the PFCAs as well as for removal of interferences. Determination of the PFCAs was carried out by LC-MS/MS in negative electrospray ionization mode. MS/MS parameters were optimized for multiple reaction monitoring of the analytes. (13)C mass labelled PFOA as a stable-isotopic internal standard, was used for calibration. The detection limits of the method ranged from 0.97 ng/g to 2.7 ng/g, with a relative standard deviation of between 5.4 and 13.5. The recoveries were evaluated for each analyte and were ranged from 77% to 120%. The t-test at 95% confidence level showed that for all the analytes, the relative recoveries did not depend on their concentrations in the explored concentration range. The effect of the matrix on MS signals (suppression or enhancement) was also evaluated. Contamination at low levels was detected for some analytes in the fish samples. The protective role of the polypropylene membrane used in μ-SPE in the elimination of matrix effects was evaluated by parallel experiments in classical dispersive solid phase extraction. The results evidently showed that the polypropylene membrane was significantly effective in reducing matrix effects. Copyright © 2014 Elsevier B.V. All rights reserved.

Er:YAG delamination of immersed biological membranes using sealed flexible hollow waveguides

NASA Astrophysics Data System (ADS)

Sagi-Dolev, A. M.; Dror, Jacob; Inberg, Alexandra; Ferencz, J. R.; Croitoru, Nathan I.

1996-04-01

The radiation of Er-YAG laser ((lambda) equals 2.94 micrometer) gives selective interaction with tissues. The extinction in soft tissues is only a few micrometers and in hard tissues is of the order of hundreds of micrometers. This makes this type of laser very suitable for treatments in dentistry, orthopedy, or ophthalmology. Because the usual silica fibers are not transmitting the radiation at lambda equals 2.94 micrometer of this laser, many applications cannot be presently performed. Fused silica hollow fibers for Er-YAG radiation were developed in our laboratory and several possible applications in dentistry, orthopedy and ophthalmology were indicated. Hole opening and implantation preparation of teeth were experimented, using Er-YAG laser and hollow plastic waveguide delivery systems. Hole drilling in cow bones was demonstrated for applications in orthopedy. A new procedure of delivering Er-YAG radiation on fibrotic membranes of inner eggshell as a model of the membranes in eyes was developed employing silica hollow waveguides of 0.5 and 0.7 mm ID or a plastic waveguide of 1.0 mm ID. For this purpose waveguides with sealed distal tip were employed to enable us to approach the delivery system through liquid media near to the membrane. This experiment demonstrates the possibility of surgical applications in vitectomy in ophthalmology using Er-YAG laser and silica hollow waveguides.

Membrane solid phase microextraction with alumina hollow fiber on line coupled with ICP-OES for the determination of trace copper, manganese and nickel in environmental water samples.

PubMed

Cui, Chao; He, Man; Hu, Bin

2011-03-15

A novel alumina hollow fiber was synthesized by sol-gel template method and was characterized by scanning electron microscopy, N(2) adsorption technique and X-ray diffraction. With the use of prepared alumina hollow fiber as extraction membrane, a new method of flow injection (FI)-membrane solid phase microextraction (MSPME) on-line coupled to inductively coupled plasma-optical emission spectrometry (ICP-OES) was developed for simultaneous determination of trace metals (Cu, Mn and Ni) in environmental water samples. The adsorption capacities of the alumina hollow fiber for Cu, Mn and Ni were found to be 6.6, 8.7 and 13.3 mg g(-1), respectively. With a preconcentration factor of 10, the limits of detection (LODs) for Cu, Mn and Ni were found to be 0.88, 0.61 and 0.38 ng mL(-1), respectively, and the relative standard deviations (RSDs) were ranging from 6.2 to 7.9% (n = 7, c = 10 ng mL(-1)). To validate the accuracy, the proposed method was applied to the analysis of certified reference material GSBZ50009-88 environmental water and the determined values are in good agreement with the certified values. The developed method was also employed for the analysis of Yangtze River water and East Lake water, and the recoveries for the spiked samples were in the range of 87.4-110.2%. Copyright © 2011 Elsevier B.V. All rights reserved.

Gravitational Role in Liquid Phase Sintering

NASA Technical Reports Server (NTRS)

Upadhyaya, Anish; Iacocca, Ronald G.; German, Randall M.

1998-01-01

To comprehensively understand the gravitational effects on the evolution of both the microstructure and the macrostructure during liquid phase sintering, W-Ni-Fe alloys with W content varying from 35 to 98 wt.% were sintered in microgravity. Compositions that slump during ground-based sintering also distort when sintered under microgravity. In ground-based sintering, low solid content alloys distort with a typical elephant-foot profile, while in microgravity, the compacts tend to spheroidize. This study shows that microstructural segregation occurs in both ground-based as well as microgravity sintering. In ground-based experiments, because of the density difference between the solid and the liquid phase, the solid content increases from top to the bottom of the sample. In microgravity, the solid content increases from periphery to the center of the samples. This study also shows that the pores during microgravity sintering act as a stable phase and attain anomalous shapes.

Colorimetric Solid Phase Extraction (CSPE): Using Color to Monitor Spacecraft Water Quality

NASA Technical Reports Server (NTRS)

Gazda, Daniel B.; Nolan, Daniel J.; Rutz, Jeffrey A.; Schultz, John R.; Siperko, Lorraine M.; Porter, Marc D.; Lipert, Robert J.; Flint, Stephanie M.; McCoy, J. Torin

2010-01-01

In August 2009, an experimental water quality monitoring kit based on Colorimetric Solid Phase Extraction (CSPE) technology was delivered to the International Space Station (ISS). The kit, called the Colorimetric Water Quality Monitoring Kit (CWQMK), was launched as a Station Development Test Objective (SDTO) experiment to evaluate the suitability of CSPE technology for routine use monitoring water quality on the ISS. CSPE is a sorption-spectrophotometric technique that combines colorimetric reagents, solid-phase extraction, and diffuse reflectance spectroscopy to quantify trace analytes in water samples. In CSPE, a known volume of sample is metered through a membrane disk that has been impregnated with an analyte-specific colorimetric reagent and any additives required to optimize the formation of the analyte-reagent complex. As the sample flows through the membrane disk, the target analyte is selectively extracted, concentrated, and complexed. Formation of the analyte-reagent complex causes a detectable change in the color of the membrane disk that is proportional to the amount of analyte present in the sample. The analyte is then quantified by measuring the color of the membrane disk surface using a hand-held diffuse reflectance spectrophotometer (DRS). The CWQMK provides the capability to measure the ionic silver (Ag +) and molecular iodine (I2) in water samples on-orbit. These analytes were selected for the evaluation of CSPE technology because they are the biocides used in the potable water storage and distribution systems on the ISS. Biocides are added to the potable water systems on spacecraft to inhibit microbial growth. On the United States (US) segment of the ISS molecular iodine serves as the biocide, while the Russian space agency utilizes silver as a biocide in their systems. In both cases, the biocides must be maintained at a level sufficient to control bacterial growth, but low enough to avoid any negative effects on crew health. For example, the presence of high levels of iodine in water can cause taste and odor issues that result in decreased water consumption by the crew. There are also concerns about potential impacts on thyroid function following exposure to high levels of iodine. With silver, there is a risk of developing argyria, an irreversible blue-gray discoloration of the skin, associated with long term consumption of water containing high concentrations of silver. The need to ensure that safe, effective levels of biocide are maintained in the potable water systems on the ISS provides a perfect platform for evaluating the suitability of CSPE technology for in-flight water quality monitoring. This paper provides an overview of CSPE technology and details on the silver and iodine methods used in the CWQMK. It also reports results obtained during in-flight analyses performed with the CWQMK and briefly discusses other potential applications for CSPE technology in both the spacecraft and terrestrial environments.

Oviposition behaviour of the soil mite Pergamasus brevicornis (Acari: Parasitidae).

PubMed

Marquardt, Tomasz; Faleńczyk-Koziróg, Katarzyna; Kaczmarek, Sławomir

2013-07-01

We observed the oviposition behaviour of the soil mite Pergamasus brevicornis Berlese (Acari: Parasitidae) using continuous video-monitoring. Oviposition consisted of six sequential phases. The first phase (I) involved inspection of the substrate. In the second phase (II) there were rhythmic movements of the first pair of legs and slight reciprocating movements of the body. The third (III) was a resting phase. In the fourth phase (IV) the gnathosoma was lowered and the body was raised. In the next phase (V) there were two sub-phases. During the first (Va), the female held the egg below the gnathosoma. In the second sub-phase (Vb), the gnathosoma moved up holding the egg, which was then placed on the substrate. The last phase (VI) involved intense 'cleaning' movements of the chelicerae and palps. During Va a protective external eggshell structure is gradually formed, involving a phase where the egg shell is sticky. After moving the egg to the substrate, the female freed her palps and chelicerae from the sticky egg shell and cleaned her gnathosomal appendages. Phases II-V took on average 207 ± 69 s.

In-vitro bioactivity, biocompatibility and dissolution studies of diopside prepared from biowaste by using sol-gel combustion method.

PubMed

Choudhary, Rajan; Vecstaudza, Jana; Krishnamurithy, G; Raghavendran, Hanumantha Rao Balaji; Murali, Malliga Raman; Kamarul, Tunku; Swamiappan, Sasikumar; Locs, Janis

2016-11-01

Diopside was synthesized from biowaste (Eggshell) by sol-gel combustion method at low calcination temperature and the influence of two different fuels (urea, l-alanine) on the phase formation temperature, physical and biological properties of the resultant diopside was studied. The synthesized materials were characterized by heating microscopy, FTIR, XRD, BET, SEM and EDAX techniques. BET analysis reveals particles were of submicron size with porosity in the nanometer range. Bone-like apatite deposition ability of diopside scaffolds was examined under static and circulation mode of SBF (Simulated Body Fluid). It was noticed that diopside has the capability to deposit HAP (hydroxyapatite) within the early stages of immersion. ICP-OES analysis indicates release of Ca, Mg, Si ions and removal of P ions from the SBF, but in different quantities from diopside scaffolds. Cytocompatability studies on human bone marrow stromal cells (hBMSCs) revealed good cellular attachment on the surface of diopside scaffolds and formation of extracellular matrix (ECM). This study suggests that the usage of eggshell biowaste as calcium source provides an effective substitute for synthetic starting materials to fabricate bioproducts for biomedical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Egg-Citing! Isolation of Protoporphyrin IX from Brown Eggshells and Its Detection by Optical Spectroscopy and Chemiluminescence

ERIC Educational Resources Information Center

Dean, Michelle L.; Miller, Tyson A.; Bruckner, Christian

2011-01-01

A simple and cost-effective laboratory experiment is described that extracts protoporphyrin IX from brown eggshells. The porphyrin is characterized by UV-vis and fluorescence spectroscopy. A chemiluminescence reaction (peroxyoxalate ester fragmentation) is performed that emits light in the UV region. When the porphyrin extract is added as a fluor…

Isolation of Biliverdin Ixa, as Its Dimethyl Ester, from Emu Eggshells

ERIC Educational Resources Information Center

Halepas, Steven; Hamchand, Randy; Lindeyer, Samuel E. D.; Bru¨ckner, Christian

2017-01-01

A laboratory experiment is described that extracts the tetrapyrrolic teal-colored biliverdin IXa, as its dimethyl ester, from commercially available emu eggshells. The extraction of ~10 mg samples of biliverdin is simple and requires two 3 h lab periods: A two-step acid digestion and liquid-liquid extraction, followed by short silica gel flash…

Dieldrin and DDT: effects on sparrow hawk eggshells and reproduction

USGS Publications Warehouse

Porter, Ron; Wiemeyer, Stanley N.

1969-01-01

Patterns of reproductive failure in declining populations of several European and North American raptorial species were duplicated experimentally with captive American sparrow hawks Falco sparverius that were given a diet containing two commonly used organochlorine insecticides. Major effects on reproduction were increased egg disappearance, increased egg destruction by parent birds, and reduced eggshell thickness.

Reconstitution of SNARE proteins into solid-supported lipid bilayer stacks and X-ray structure analysis.

PubMed

Xu, Yihui; Kuhlmann, Jan; Brennich, Martha; Komorowski, Karlo; Jahn, Reinhard; Steinem, Claudia; Salditt, Tim

2018-02-01

SNAREs are known as an important family of proteins mediating vesicle fusion. For various biophysical studies, they have been reconstituted into supported single bilayers via proteoliposome adsorption and rupture. In this study we extended this method to the reconstitution of SNAREs into supported multilamellar lipid membranes, i.e. oriented multibilayer stacks, as an ideal model system for X-ray structure analysis (X-ray reflectivity and diffraction). The reconstitution was implemented through a pathway of proteomicelle, proteoliposome and multibilayer. To monitor the structural evolution in each step, we used small-angle X-ray scattering for the proteomicelles and proteoliposomes, followed by X-ray reflectivity and grazing-incidence small-angle scattering for the multibilayers. Results show that SNAREs can be successfully reconstituted into supported multibilayers, with high enough orientational alignment for the application of surface sensitive X-ray characterizations. Based on this protocol, we then investigated the effect of SNAREs on the structure and phase diagram of the lipid membranes. Beyond this application, this reconstitution protocol could also be useful for X-ray analysis of many further membrane proteins. Copyright © 2017 Elsevier B.V. All rights reserved.

Eggshell Porosity Provides Insight on Evolution of Nesting in Dinosaurs.

PubMed

Tanaka, Kohei; Zelenitsky, Darla K; Therrien, François

2015-01-01

Knowledge about the types of nests built by dinosaurs can provide insight into the evolution of nesting and reproductive behaviors among archosaurs. However, the low preservation potential of their nesting materials and nesting structures means that most information can only be gleaned indirectly through comparison with extant archosaurs. Two general nest types are recognized among living archosaurs: 1) covered nests, in which eggs are incubated while fully covered by nesting material (as in crocodylians and megapodes), and 2) open nests, in which eggs are exposed in the nest and brooded (as in most birds). Previously, dinosaur nest types had been inferred by estimating the water vapor conductance (i.e., diffusive capacity) of their eggs, based on the premise that high conductance corresponds to covered nests and low conductance to open nests. However, a lack of statistical rigor and inconsistencies in this method render its application problematic and its validity questionable. As an alternative we propose a statistically rigorous approach to infer nest type based on large datasets of eggshell porosity and egg mass compiled for over 120 extant archosaur species and 29 archosaur extinct taxa/ootaxa. The presence of a strong correlation between eggshell porosity and nest type among extant archosaurs indicates that eggshell porosity can be used as a proxy for nest type, and thus discriminant analyses can help predict nest type in extinct taxa. Our results suggest that: 1) covered nests are likely the primitive condition for dinosaurs (and probably archosaurs), and 2) open nests first evolved among non-avian theropods more derived than Lourinhanosaurus and were likely widespread in non-avian maniraptorans, well before the appearance of birds. Although taphonomic evidence suggests that basal open nesters (i.e., oviraptorosaurs and troodontids) were potentially the first dinosaurs to brood their clutches, they still partially buried their eggs in sediment. Open nests with fully exposed eggs only became widespread among Euornithes. A potential co-evolution of open nests and brooding behavior among maniraptorans may have freed theropods from the ground-based restrictions inherent to covered nests and allowed the exploitation of alternate nesting locations. These changes in nesting styles and behaviors thus may have played a role in the evolutionary success of maniraptorans (including birds).

Eggshell Porosity Provides Insight on Evolution of Nesting in Dinosaurs

PubMed Central

2015-01-01

Knowledge about the types of nests built by dinosaurs can provide insight into the evolution of nesting and reproductive behaviors among archosaurs. However, the low preservation potential of their nesting materials and nesting structures means that most information can only be gleaned indirectly through comparison with extant archosaurs. Two general nest types are recognized among living archosaurs: 1) covered nests, in which eggs are incubated while fully covered by nesting material (as in crocodylians and megapodes), and 2) open nests, in which eggs are exposed in the nest and brooded (as in most birds). Previously, dinosaur nest types had been inferred by estimating the water vapor conductance (i.e., diffusive capacity) of their eggs, based on the premise that high conductance corresponds to covered nests and low conductance to open nests. However, a lack of statistical rigor and inconsistencies in this method render its application problematic and its validity questionable. As an alternative we propose a statistically rigorous approach to infer nest type based on large datasets of eggshell porosity and egg mass compiled for over 120 extant archosaur species and 29 archosaur extinct taxa/ootaxa. The presence of a strong correlation between eggshell porosity and nest type among extant archosaurs indicates that eggshell porosity can be used as a proxy for nest type, and thus discriminant analyses can help predict nest type in extinct taxa. Our results suggest that: 1) covered nests are likely the primitive condition for dinosaurs (and probably archosaurs), and 2) open nests first evolved among non-avian theropods more derived than Lourinhanosaurus and were likely widespread in non-avian maniraptorans, well before the appearance of birds. Although taphonomic evidence suggests that basal open nesters (i.e., oviraptorosaurs and troodontids) were potentially the first dinosaurs to brood their clutches, they still partially buried their eggs in sediment. Open nests with fully exposed eggs only became widespread among Euornithes. A potential co-evolution of open nests and brooding behavior among maniraptorans may have freed theropods from the ground-based restrictions inherent to covered nests and allowed the exploitation of alternate nesting locations. These changes in nesting styles and behaviors thus may have played a role in the evolutionary success of maniraptorans (including birds). PMID:26605799

Superhydrophobic and superhydrophilic surface-enhanced separation performance of porous inorganic membranes for biomass-to-biofuel conversion applications

DOE PAGES

Hu, Michael Z.; Engtrakul, Chaiwat; Bischoff, Brian L.; ...

2016-11-14

A new class of inorganic-based membranes, i.e., High-Performance Architectured Surface Selective (HiPAS) membranes, is introduced to provide high perm-selective flux by exploiting unique separation mechanisms induced by superhydrophobic or superhydrophilic surface interactions and confined capillary condensation in enlarged membrane pores (~8 nm). The super-hydro-tunable HiPAS membranes were originally developed for the purpose of bio-oil/biofuel processing to achieve selective separations at higher flux relative to size selective porous membranes (e.g., inorganic zeolite-based membranes) and better high-temperature tolerance than polymer membranes (>250 C) for hot vapor processing. Due to surface-enhanced separation selectivity, HiPAS membranes can thus possibly enable larger pores to facilitatemore » large-flux separations by increasing from sub-nanometer pores to mesopores (2-50 nm) for vapor phase or micron-scale pores for liquid phase separations. In this paper, we describe an innovative membrane concept and a materials synthesis strategy to fabricate HiPAS membranes, and demonstrate selective permeation in both vapor- and liquid-phase applications. High permeability and selectivity were demonstrated using surrogate mixtures, such as ethanol-water, toluene-water, and toluene-phenol-water. The overall membrane evaluation results show promise for the future processing of biomass pyrolysis and upgraded product vapors and condensed liquid bio-oil intermediates.« less

Fabrication of ultrathin solid electrolyte membranes of β-Li 3PS 4 nanoflakes by evaporation-induced self-assembly for all-solid-state batteries

DOE PAGES

Wang, Hui; Hood, Zachary D.; Xia, Younan; ...

2016-04-25

All-solid-state lithium batteries are attractive candidates for next-generation energy storage devices because of their anticipated high energy density and intrinsic safety. Owing to their excellent ionic conductivity and stability with metallic lithium anodes, nanostructured lithium thiophosphate solid electrolytes such as β-Li 3PS 4 have found use in the fabrication of all-solid lithium batteries for large-scale energy storage systems. However, current methods for preparing air-sensitive solid electrolyte membranes of lithium thiophosphates can only generate thick membranes that compromise the battery's gravimetric/volumetric energy density and thus its rate performance. To overcome this limitation, the solid electrolyte's thickness needs to be effectively decreasedmore » to achieve ideal energy density and enhanced rate performance. In this paper, we show that the evaporation-induced self-assembly (EISA) technique produces ultrathin membranes of a lithium thiophosphate solid electrolyte with controllable thicknesses between 8 and 50 μm while maintaining the high ionic conductivity of β-Li 3PS 4 and stability with metallic lithium anodes up to 5 V. Finally, it is clearly demonstrated that this facile EISA approach allows for the preparation of ultrathin lithium thiophosphate solid electrolyte membranes for all-solid-state batteries.« less

Isoleucine epimerization and amino acid composition in molecular-weight separations of Pleistocene Genyornis eggshell

NASA Astrophysics Data System (ADS)

Kaufman, Darrell S.; Miller, Gifford H.

1995-07-01

This study explores the geochronological utility and analytical reproducibility of separating the high-molecular-weight fraction (HMW) from eggshells of the extinct late Pleistocene ratite, Genyornis, using disposable, prepacked gel-filtration columns. The superior integrity of ratite eggshell for the retention of amino acids indicates that this biomineral is better suited for this type of investigation than previously studied molluscan shell. To evaluate the reproducibility of the gel-filtration technique, we analyzed triplicate subsamples of three eggshells of different ages. The reproducibility, based on the average intrashell variation (coefficient of variation; CV) in the extent of isoleucine epimerization (aIle/Ile) in the HMW (enriched in molecules ca. >10,000 MW) is 3%, well within the range appropriate for geochronological purposes. The average intrashell variation in the total amino acid concentration (Σ[aa]) of the HMW is 5%, somewhat better than for the total acid hydrolysate (TOTAL) of the same samples (7%). To evaluate the relation between molecular weight and the rate of isoleucine epimerization, three molecular-weight fractions were separated using gel filtration, plus the naturally hydrolyzed free fraction (FREE), for each of four fossil eggshells. AIle/Ile increases with decreasing molecular weight in all shells, with a ca. sixfold to ninefold difference in ratios between the HMW andFREE, and a ca. fivefold difference between the HMW andTOTAL. Although linear correlations between aIle/Ile measured in each molecular-weight fraction and in theTOTAL are all highly significant (r ⩾ 0.951), the relation between the extent of epimerization in the HMW and in the TOTAL is best expressed as an exponential function (r = 0.951). This relation is consistent with the idea that, as the epimerization reaction approaches equilibrium in theTOTAL (ca. aIle/Ile > 1.1), its rate decreases beyond that of the HMW. The amino acid composition (relative percent of eight amino acids or combinations of amino acids) is more uniform in the HMW of the four samples compared to lower-molecular-weight fractions. The greater "compositional stability" of the HMW indicates that it contains a residuum of macromolecules that have not been affected by the diagenetically driven changes observed in lower-molecular-weight fractions.

Lamellar Biogels: Fluid-Membrane-Based Hydrogels Containing Polymer Lipids

NASA Astrophysics Data System (ADS)

Warriner, Heidi E.; Idziak, Stefan H. J.; Slack, Nelle L.; Davidson, Patrick; Safinya, Cyrus R.

1996-02-01

A class of lamellar biological hydrogels comprised of fluid membranes of lipids and surfactants with small amounts of low molecular weight poly(ethylene glycol)-derived polymer lipids (PEG-lipids) were studied by x-ray diffraction, polarized light microscopy, and rheometry. In contrast to isotropic hydrogels of polymer networks, these membrane-based birefringent liquid crystalline biogels, labeled Lα,g, form the gel phase when water is added to the liquid-like lamellar L_α phase, which reenters a liquid-like mixed phase upon further dilution. Furthermore, gels with larger water content require less PEG-lipid to remain stable. Although concentrated (~50 weight percent) mixtures of free PEG (molecular weight, 5000) and water do not gel, gelation does occur in mixtures containing as little as 0.5 weight percent PEG-lipid. A defining signature of the Lα,g regime as it sets in from the fluid lamellar L_α phase is the proliferation of layer-dislocation-type defects, which are stabilized by the segregation of PEG-lipids to the defect regions of high membrane curvature that connect the membranes.

Passive membrane penetration by ZnO nanoparticles is driven by the interplay of electrostatic and phase boundary conditions.

PubMed

Tiwari, Anuj; Prince, Ashutosh; Arakha, Manoranjan; Jha, Suman; Saleem, Mohammed

2018-02-15

The internalization of nanoparticles through the biological membrane is of immense importance for biomedical applications. A fundamental understanding of the lipid specificity and the role of the membrane biochemical and physical forces at play in modulating penetration are lacking. The current understanding of nanoparticle-membrane interaction is drawn mostly from computational studies and lacks sufficient experimental evidence. Herein, using confocal fluorescence imaging and potentiometric dye-based fluorimetry, we first investigated the interaction of ZnONP in both multi-component and individual lipid membranes using cell-like giant unilamellar vesicles to dissect the lipid specificity; also, we investigated the changes in membrane order, anisotropy and hydrophobicity. ZnONP was found to interact with phosphatidylinositol and phosphatidylcholine head-group-containing lipids specifically. We further investigated the interaction of ZnONP with three physiologically relevant membrane conditions varying in composition and dipole potential. We found that ZnONP interaction leads to a photoinduced enhancement of the partial-to-complete phase separation depending upon the membrane composition and cholesterol content. Interestingly, while the lipid order of a partially-phase-separated membrane remained unchanged upon ZnONP crowding, a fully-phase-separated membrane showed an increase in the lipid order. Strikingly, ZnONP crowding induced a contrasting effect on the fluorescence anisotropy of the membrane upon binding to the two membrane conditions, in line with the measured diffusion coefficient. ZnONP seems to preferentially penetrate through the liquid disordered areas of the membrane and the boundaries of the phase-separated regions driven by the interplay between the electrostatics and phase boundary conditions, which are collectively dictated by the composition and ZnONP-induced lipid reorganization. The results may lead to a greater understanding of the interplay of membrane parameters and ZnONP interaction in driving passive penetration.

Calcium-selective electrodes based on photo-cured polyurethane-acrylate membranes covalently attached to methacrylate functionalized poly(3,4-ethylenedioxythiophene) as solid-contact.

PubMed

Ocaña, Cristina; Abramova, Natalia; Bratov, Andrey; Lindfors, Tom; Bobacka, Johan

2018-08-15

We report here the fabrication of solid-contact calcium-selective electrodes (Ca 2+ -SCISEs) made of a polyurethane acrylate ion-selective membrane (ISM) that was covalently attached to the underlying ion-to-electron transducer (solid-contact). Methacrylate-functionalized poly(3,4-ethylenedioxythiophene) (Meth-PEDOT) and Meth-PEDOT films containing either multiwalled carbon nanotubes (MWCNT) or carboxylated MWCNT (cMWCNT) were used as solid contacts. The solid contacts were deposited by drop-casting on screen-printed electrodes and characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and potentiometry. Covalent binding between the solid contact and the ISM was obtained via photopolymerization in order to increase the robustness of the Ca 2+ -SCISEs. The performance of the Ca 2+ -SCISEs was studied by measuring their potentiometric response and their sensitivity to light, oxygen and carbon dioxide. Meth-PEDOT was found to be a promising solid-contact material to develop low-cost and easy to prepare ISEs. Copyright © 2018 Elsevier B.V. All rights reserved.

Solid polymer electrolyte composite membrane comprising laser micromachined porous support

DOEpatents

Liu, Han [Waltham, MA; LaConti, Anthony B [Lynnfield, MA; Mittelsteadt, Cortney K [Natick, MA; McCallum, Thomas J [Ashland, MA

2011-01-11

A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a rigid, non-electrically-conducting support, the support preferably being a sheet of polyimide having a thickness of about 7.5 to 15 microns. The support has a plurality of cylindrical pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores, which preferably have a diameter of about 5 microns, are made by laser micromachining and preferably are arranged in a defined pattern, for example, with fewer pores located in areas of high membrane stress and more pores located in areas of low membrane stress. The pores are filled with a first solid polymer electrolyte, such as a perfluorosulfonic acid (PFSA) polymer. A second solid polymer electrolyte, which may be the same as or different than the first solid polymer electrolyte, may be deposited over the top and/or bottom of the first solid polymer electrolyte.

Solid polymer electrolyte composite membrane comprising plasma etched porous support

DOEpatents

Liu, Han; LaConti, Anthony B.

2010-10-05

A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a rigid, non-electrically-conducting support, the support preferably being a sheet of polyimide having a thickness of about 7.5 to 15 microns. The support has a plurality of cylindrical pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores, which preferably have a diameter of about 0.1 to 5 microns, are made by plasma etching and preferably are arranged in a defined pattern, for example, with fewer pores located in areas of high membrane stress and more pores located in areas of low membrane stress. The pores are filled with a first solid polymer electrolyte, such as a perfluorosulfonic acid (PFSA) polymer. A second solid polymer electrolyte, which may be the same as or different than the first solid polymer electrolyte, may be deposited over the top and/or bottom of the first solid polymer electrolyte.

Effects of Partial Replacement of Eggshell Powder by Halloysite Nanotubes on the Properties of Polyvinyl Alcohol Composites

NASA Astrophysics Data System (ADS)

Alias, N. F.; Ismail, H.

2018-06-01

Polyvinyl alcohol (PVA)/eggshell powder (ESP) were prepared via solution casting method. The effects of gradual replacement of ESP by halloysite nanotubes (HNTs) were investigated based on tensile properties, physical properties and biodegradability. The main objective is to study the effect of hybrid fillers and also to compare the properties of PVA/ESP composite with conventional filler, HNT. The tensile properties decreased with increasing HNT loading. Scanning electron microscopy (SEM) studies showed that agglomeration of filler were present throughout the composites. Due to the presence of hydroxyl group on the outer and inner surface of HNT, the water absorption and water vapor transmisibility were found to increase with increasing HNTs loading. The biodegradability of film filled with HNT is lower compared to the film filled with ESP.

Biomimetic Dissolution: A Tool to Predict Amorphous Solid Dispersion Performance.

PubMed

Puppolo, Michael M; Hughey, Justin R; Dillon, Traciann; Storey, David; Jansen-Varnum, Susan

2017-11-01

The presented study describes the development of a membrane permeation non-sink dissolution method that can provide analysis of complete drug speciation and emulate the in vivo performance of poorly water-soluble Biopharmaceutical Classification System class II compounds. The designed membrane permeation methodology permits evaluation of free/dissolved/unbound drug from amorphous solid dispersion formulations with the use of a two-cell apparatus, biorelevant dissolution media, and a biomimetic polymer membrane. It offers insight into oral drug dissolution, permeation, and absorption. Amorphous solid dispersions of felodipine were prepared by hot melt extrusion and spray drying techniques and evaluated for in vitro performance. Prior to ranking performance of extruded and spray-dried felodipine solid dispersions, optimization of the dissolution methodology was performed for parameters such as agitation rate, membrane type, and membrane pore size. The particle size and zeta potential were analyzed during dissolution experiments to understand drug/polymer speciation and supersaturation sustainment of felodipine solid dispersions. Bland-Altman analysis was performed to measure the agreement or equivalence between dissolution profiles acquired using polymer membranes and porcine intestines and to establish the biomimetic nature of the treated polymer membranes. The utility of the membrane permeation dissolution methodology is seen during the evaluation of felodipine solid dispersions produced by spray drying and hot melt extrusion. The membrane permeation dissolution methodology can suggest formulation performance and be employed as a screening tool for selection of candidates to move forward to pharmacokinetic studies. Furthermore, the presented model is a cost-effective technique.

Small gene family encoding an eggshell (chorion) protein of the human parasite Schistosoma mansoni

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

Bobek, L.A.; Rekosh, D.M.; Lo Verde, P.T.

1988-08-01

The authors isolated six independent genomic clones encoding schistosome chorion or eggshell proteins from a Schistosoma mansoni genomic library. A linkage map of five of the clones spanning 35 kilobase pairs (kbp) of the S. mansoni genome was constructed. The region contained two eggshell protein genes closely linked, separated by 7.5 kbp of intergenic DNA. The two genes of the cluster were arranged in the same orientation, that is, they were transcribed from the same strand. The sixth clone probably represents a third copy of the eggshell gene that is not contained within the 35-kbp region. The 5- end ofmore » the mRNA transcribed from these genes was defined by primer extension directly off the RNA. The ATCAT cap site sequence was homologous to a silkmoth chorion PuTCATT cap site sequence, where Pu indicates any purine. DNA sequence analysis showed that there were no introns in these genes. The DNA sequences of the three genes were very homologous to each other and to a cDNA clone, pSMf61-46, differing only in three or four nucleotices. A multiple TATA box was located at positions -23 to -31, and a CAAAT sequence was located at -52 upstream of the eggshell transcription unit. Comparison of sequences in regions further upstream with silkmoth and Drosophila sequences revealed very short elements that were shared. One such element, TCACGT, recently shown to be an essential cis-regulatory element for silkmoth chorion gene promoter function, was found at a similar position in all three organisms.« less

Infectious bronchitis virus and brown shell colour: Australian strains of infectious bronchitis virus affect brown eggshell colour in commercial laying hens differently.

PubMed

Samiullah, Sami; Roberts, Juliet; Chousalkar, Kapil

2016-10-01

The aim of the current study was to assess any effect of wild and vaccine Australian infectious bronchitis virus (IBV) strains on shell colour in brown-shelled eggs. In Experiment 1, eggs were collected from day 1 to day 13 post-inoculation (p.i.) from unvaccinated laying hens challenged with IBV wild strains T and N1/88 and from a negative control group of hens. In Experiment 2, eggs were collected from 2 to 22 days p.i. from unvaccinated and vaccinated laying hens challenged with either a wild or a vaccine strain of IBV. In Experiment 1, there was a significant effect (P < 0.05) of day p.i. and of viral strain on shell reflectivity, L* and protoporphyrin IX (PP IX) in eggshells, with and without cuticle. The mean PP IX/g of shell with and without cuticle was significantly higher on day 1 p.i. compared to day 7, after which PP IX increased with day p.i. In Experiment 2, shell reflectivity and L* increased and PP IX decreased with increased day p.i. until day 12. Shell reflectivity and L* decreased slightly after day 12 and increased again towards day 22. Shell reflectivity, L* and PP IX were not significantly different for eggshells from unvaccinated and vaccinated laying hens in the intact eggshell, but were significantly different in shells from which cuticle had been removed. In conclusion, the IBV strains reduced the intensity of brown shell colour to different extents with a lower amount of PP IX in eggshells.

Assessment of diagenetic alteration of dinosaur eggshells through petrography and geochemical analysis

NASA Astrophysics Data System (ADS)

Enriquez, M. V.; Eagle, R.; Eiler, J. M.; Tripati, A. K.; Ramirez, P. C.; Loyd, S. J.; Chiappe, L.; Montanari, S.; Norell, M.; Tuetken, T.

2012-12-01

Carbonate clumped isotope analysis of fossil eggshells has the potential to constrain both the physiology of extinct animals and, potentially, paleoenvironmental conditions, especially when coupled with isotopic measurements of co-occurring soil carbonates. Eggshell samples from both modern vertebrates and Cretaceous Hadrosaurid, Oviraptorid, Titanosaur, Hypselosaurus, Faveoolithus, dinosaur fossils have been collected from Auca Mahuevo, Argentina and Rousett, France, amongst other locations, for geochemical analysis to determine if isotopic signatures could be used to indicate warm- or cold-bloodedness. In some locations soil carbonates were also analyzed to constrain environmental temperatures. In order to test the validity of the geochemical results, an extensive study was undertaken to establish degree of diagenetic alteration. Petrographic and cathodoluminescence characterization of the eggshells were used to assess diagenetic alteration. An empirical 1-5 point scale was used to assign each sample an alteration level, and the observations were then compared with the geochemical results. Specimens displayed a wide range of alteration states. Some of which were well preserved and others highly altered. Another group seemed to be structural intact and only under cathodoluminescence was alteration clearly observed. In the majority of samples, alteration level was found to be predictably related to geochemical results. From specimens with little evidence for diagenesis, carbonate clumped isotope signatures support high (37-40°C) body temperature for Titanosaurid dinosaurs, but potentially lower body temperatures for other taxa. If these data do, in fact, represent original eggshell growth temperatures, these results support variability in body temperature amongst Cretaceous dinosaurs and potentially are consistent with variations between adult body temperature and size — a characteristic of 'gigantothermy'.

Flexible, solid-state, ion-conducting membrane with 3D garnet nanofiber networks for lithium batteries

PubMed Central

Fu, Kun (Kelvin); Gong, Yunhui; Dai, Jiaqi; Gong, Amy; Han, Xiaogang; Yao, Yonggang; Wang, Chengwei; Wang, Yibo; Chen, Yanan; Yan, Chaoyi; Li, Yiju; Wachsman, Eric D.; Hu, Liangbing

2016-01-01

Beyond state-of-the-art lithium-ion battery (LIB) technology with metallic lithium anodes to replace conventional ion intercalation anode materials is highly desirable because of lithium’s highest specific capacity (3,860 mA/g) and lowest negative electrochemical potential (∼3.040 V vs. the standard hydrogen electrode). In this work, we report for the first time, to our knowledge, a 3D lithium-ion–conducting ceramic network based on garnet-type Li6.4La3Zr2Al0.2O12 (LLZO) lithium-ion conductor to provide continuous Li+ transfer channels in a polyethylene oxide (PEO)-based composite. This composite structure further provides structural reinforcement to enhance the mechanical properties of the polymer matrix. The flexible solid-state electrolyte composite membrane exhibited an ionic conductivity of 2.5 × 10−4 S/cm at room temperature. The membrane can effectively block dendrites in a symmetric Li | electrolyte | Li cell during repeated lithium stripping/plating at room temperature, with a current density of 0.2 mA/cm2 for around 500 h and a current density of 0.5 mA/cm2 for over 300 h. These results provide an all solid ion-conducting membrane that can be applied to flexible LIBs and other electrochemical energy storage systems, such as lithium–sulfur batteries. PMID:27307440

Flexible, solid-state, ion-conducting membrane with 3D garnet nanofiber networks for lithium batteries

NASA Astrophysics Data System (ADS)

Kun, Kelvin; Gong, Yunhui; Dai, Jiaqi; Gong, Amy; Han, Xiaogang; Yao, Yonggang; Wang, Chengwei; Wang, Yibo; Chen, Yanan; Yan, Chaoyi; Li, Yiju; Wachsman, Eric D.; Hu, Liangbing

2016-06-01

Beyond state-of-the-art lithium-ion battery (LIB) technology with metallic lithium anodes to replace conventional ion intercalation anode materials is highly desirable because of lithium's highest specific capacity (3,860 mA/g) and lowest negative electrochemical potential (˜3.040 V vs. the standard hydrogen electrode). In this work, we report for the first time, to our knowledge, a 3D lithium-ion-conducting ceramic network based on garnet-type Li6.4La3Zr2Al0.2O12 (LLZO) lithium-ion conductor to provide continuous Li+ transfer channels in a polyethylene oxide (PEO)-based composite. This composite structure further provides structural reinforcement to enhance the mechanical properties of the polymer matrix. The flexible solid-state electrolyte composite membrane exhibited an ionic conductivity of 2.5 × 10-4 S/cm at room temperature. The membrane can effectively block dendrites in a symmetric Li | electrolyte | Li cell during repeated lithium stripping/plating at room temperature, with a current density of 0.2 mA/cm2 for around 500 h and a current density of 0.5 mA/cm2 for over 300 h. These results provide an all solid ion-conducting membrane that can be applied to flexible LIBs and other electrochemical energy storage systems, such as lithium-sulfur batteries.

Equations of State and Phase Diagrams of Ammonia

ERIC Educational Resources Information Center

Glasser, Leslie

2009-01-01

We present equations of state relating the phases and a three-dimensional phase diagram for ammonia with its solid, liquid, and vapor phases, based on fitted authentic experimental data and including recent information on the high-pressure solid phases. This presentation follows similar articles on carbon dioxide and water published in this…

Determination of free and deconjugated testosterone and epitestosterone in urine using SPME and LC-MS/MS.

PubMed

Zhan, Yanwei; Musteata, Florin M; Basset, Fabien A; Pawliszyn, Janusz

2011-01-01

A thin sheet of polydimethylsilosane membrane was used as an extraction phase for solid-phase microextraction. Compared with fiber or rod solid-phase microextraction geometries, the thin film exhibited much higher extraction capacity without sacrificing extraction time due to its higher area-to-volume ratio. The analytical method involved direct extraction of unconjugated testosterone (T) and epitestosterone (ET) followed by separation on a C18 column and detection by selected reaction monitoring in positive ionization mode. The limit of detection was 1 ng/l for both T and ET. After method validation, free (unconjugated) T and ET were extracted and quantified in real samples. Since T and ET are extensively metabolized, the proposed method was also applied to extract the steroids after enzymatic deconjugation of urinary-excreted steroid glucuronides. The proposed method allows quantification of both conjugated and unconjugated steroids, and revealed that there was a change in the ratio of T to ET after enzymatic deconjugation, indicating different rates of metabolism.

Ethanol effects on binary and ternary supported lipid bilayers with gel/fluid domains and lipid rafts.

PubMed

Marquês, Joaquim T; Viana, Ana S; De Almeida, Rodrigo F M

2011-01-01

Ethanol-lipid bilayer interactions have been a recurrent theme in membrane biophysics, due to their contribution to the understanding of membrane structure and dynamics. The main purpose of this study was to assess the interplay between membrane lateral heterogeneity and ethanol effects. This was achieved by in situ atomic force microscopy, following the changes induced by sequential ethanol additions on supported lipid bilayers formed in the absence of alcohol. Binary phospholipid mixtures with a single gel phase, dipalmitoylphosphatidylcholine (DPPC)/cholesterol, gel/fluid phase coexistence DPPC/dioleoylphosphatidylcholine (DOPC), and ternary lipid mixtures containing cholesterol, mimicking lipid rafts (DOPC/DPPC/cholesterol and DOPC/sphingomyelin/cholesterol), i.e., with liquid ordered/liquid disordered (ld/lo) phase separation, were investigated. For all compositions studied, and in two different solid supports, mica and silicon, domain formation or rearrangement accompanied by lipid bilayer thinning and expansion was observed. In the case of gel/fluid coexistence, low ethanol concentrations lead to a marked thinning of the fluid but not of the gel domains. In the case of ld/lo all the bilayer thins simultaneously by a similar extent. In both cases, only the more disordered phase expanded significantly, indicating that ethanol increases the proportion of disordered domains. Water/bilayer interfacial tension variation and freezing point depression, inducing acyl chain disordering (including opening and looping), tilting, and interdigitation, are probably the main cause for the observed changes. The results presented herein demonstrate that ethanol influences the bilayer properties according to membrane lateral organization. Copyright © 2010 Elsevier B.V. All rights reserved.

Basic investigation into the electrical performance of solid electrolyte membranes

NASA Technical Reports Server (NTRS)

Richter, R.

1982-01-01

The electrical performance of solid electrolyte membranes was investigated analytically and the results were compared with experimental data. It is concluded that in devices that are used for pumping oxygen the major power losses have to be attributed to the thin film electrodes. Relations were developed by which the effectiveness of tubular solid electrolyte membranes can be determined and the optimum length evaluated. The observed failure of solid electrolyte tube membranes in very localized areas is explained by the highly non-uniform current distribution in the membranes. The analysis points to a possible contact resistance between the electrodes and the solid electrolyte material. This possible contact resistance remains to be investigated experimentally. It is concluded that film electrodes are not appropriate for devices which operate with current flow, i.e., pumps though they can be employed without reservation in devices that measure oxygen pressures if a limited increase in the response time can be tolerated.

Innate humoural immunity is related to eggshell bacterial load of European birds: a comparative analysis.

PubMed

Soler, Juan José; Peralta-Sánchez, Juan Manuel; Flensted-Jensen, Einar; Martín-Platero, Antonio Manuel; Møller, Anders Pape

2011-09-01

Fitness benefits associated with the development of a costly immune system would include not only self-protection against pathogenic microorganisms but also protection of host offspring if it reduces the probability and the rate of vertical transmission of microorganisms. This possibility predicts a negative relationship between probabilities of vertical transmission of symbionts and level of immune response that we here explore inter-specifically. We estimated eggshell bacterial loads by culturing heterotrophic bacteria, Enterococcus, Staphylococcus and Enterobacteriaceae on the eggshells of 29 species of birds as a proxy of vertical transmission of bacteria from mother to offspring. For this pool of species, we also estimated innate immune response (natural antibody and complement (lysis)) of adults, which constitute the main defence against bacterial infection. Multivariate general linear models revealed the predicted negative association between natural antibodies and density of bacteria on the eggshell of 19 species of birds for which we sampled the eggs in more than one nest. Univariate analyses revealed significant associations for heterotrophic bacteria and for Enterobacteriaceae, a group of bacteria that includes important pathogens of avian embryos. Therefore, these results suggest a possible trans-generational benefit of developing a strong immune system by reducing vertical transmission of pathogens.

Innate humoural immunity is related to eggshell bacterial load of European birds: a comparative analysis

NASA Astrophysics Data System (ADS)

Soler, Juan José; Peralta-Sánchez, Juan Manuel; Flensted-Jensen, Einar; Martín-Platero, Antonio Manuel; Møller, Anders Pape

2011-09-01

Fitness benefits associated with the development of a costly immune system would include not only self-protection against pathogenic microorganisms but also protection of host offspring if it reduces the probability and the rate of vertical transmission of microorganisms. This possibility predicts a negative relationship between probabilities of vertical transmission of symbionts and level of immune response that we here explore inter-specifically. We estimated eggshell bacterial loads by culturing heterotrophic bacteria, Enterococcus, Staphylococcus and Enterobacteriaceae on the eggshells of 29 species of birds as a proxy of vertical transmission of bacteria from mother to offspring. For this pool of species, we also estimated innate immune response (natural antibody and complement (lysis)) of adults, which constitute the main defence against bacterial infection. Multivariate general linear models revealed the predicted negative association between natural antibodies and density of bacteria on the eggshell of 19 species of birds for which we sampled the eggs in more than one nest. Univariate analyses revealed significant associations for heterotrophic bacteria and for Enterobacteriaceae, a group of bacteria that includes important pathogens of avian embryos. Therefore, these results suggest a possible trans-generational benefit of developing a strong immune system by reducing vertical transmission of pathogens.

Large-scale preparation of clove essential oil and eugenol-loaded liposomes using a membrane contactor and a pilot plant.

PubMed

Sebaaly, Carine; Greige-Gerges, Hélène; Agusti, Géraldine; Fessi, Hatem; Charcosset, Catherine

2016-01-01

Based on our previous study where optimal conditions were defined to encapsulate clove essential oil (CEO) into liposomes at laboratory scale, we scaled-up the preparation of CEO and eugenol (Eug)-loaded liposomes using a membrane contactor (600 mL) and a pilot plant (3 L) based on the principle of ethanol injection method, both equipped with a Shirasu Porous Glass membrane for injection of the organic phase into the aqueous phase. Homogenous, stable, nanometric-sized and multilamellar liposomes with high phospholipid, Eug loading rates and encapsulation efficiency of CEO components were obtained. Saturation of phospholipids and drug concentration in the organic phase may control the liposome stability. Liposomes loaded with other hydrophobic volatile compounds could be prepared at large scale using the ethanol injection method and a membrane for injection.

Enthalpy-based multiple-relaxation-time lattice Boltzmann method for solid-liquid phase-change heat transfer in metal foams.

PubMed

Liu, Qing; He, Ya-Ling; Li, Qing

2017-08-01

In this paper, an enthalpy-based multiple-relaxation-time (MRT) lattice Boltzmann (LB) method is developed for solid-liquid phase-change heat transfer in metal foams under the local thermal nonequilibrium (LTNE) condition. The enthalpy-based MRT-LB method consists of three different MRT-LB models: one for flow field based on the generalized non-Darcy model, and the other two for phase-change material (PCM) and metal-foam temperature fields described by the LTNE model. The moving solid-liquid phase interface is implicitly tracked through the liquid fraction, which is simultaneously obtained when the energy equations of PCM and metal foam are solved. The present method has several distinctive features. First, as compared with previous studies, the present method avoids the iteration procedure; thus it retains the inherent merits of the standard LB method and is superior to the iteration method in terms of accuracy and computational efficiency. Second, a volumetric LB scheme instead of the bounce-back scheme is employed to realize the no-slip velocity condition in the interface and solid phase regions, which is consistent with the actual situation. Last but not least, the MRT collision model is employed, and with additional degrees of freedom, it has the ability to reduce the numerical diffusion across the phase interface induced by solid-liquid phase change. Numerical tests demonstrate that the present method can serve as an accurate and efficient numerical tool for studying metal-foam enhanced solid-liquid phase-change heat transfer in latent heat storage. Finally, comparisons and discussions are made to offer useful information for practical applications of the present method.

Enthalpy-based multiple-relaxation-time lattice Boltzmann method for solid-liquid phase-change heat transfer in metal foams

NASA Astrophysics Data System (ADS)

Liu, Qing; He, Ya-Ling; Li, Qing

2017-08-01

In this paper, an enthalpy-based multiple-relaxation-time (MRT) lattice Boltzmann (LB) method is developed for solid-liquid phase-change heat transfer in metal foams under the local thermal nonequilibrium (LTNE) condition. The enthalpy-based MRT-LB method consists of three different MRT-LB models: one for flow field based on the generalized non-Darcy model, and the other two for phase-change material (PCM) and metal-foam temperature fields described by the LTNE model. The moving solid-liquid phase interface is implicitly tracked through the liquid fraction, which is simultaneously obtained when the energy equations of PCM and metal foam are solved. The present method has several distinctive features. First, as compared with previous studies, the present method avoids the iteration procedure; thus it retains the inherent merits of the standard LB method and is superior to the iteration method in terms of accuracy and computational efficiency. Second, a volumetric LB scheme instead of the bounce-back scheme is employed to realize the no-slip velocity condition in the interface and solid phase regions, which is consistent with the actual situation. Last but not least, the MRT collision model is employed, and with additional degrees of freedom, it has the ability to reduce the numerical diffusion across the phase interface induced by solid-liquid phase change. Numerical tests demonstrate that the present method can serve as an accurate and efficient numerical tool for studying metal-foam enhanced solid-liquid phase-change heat transfer in latent heat storage. Finally, comparisons and discussions are made to offer useful information for practical applications of the present method.

Chemical compositions, methods of making the chemical compositions, and structures made from the chemical compositions

DOEpatents

Yang, Lei; Cheng, Zhe; Liu, Ze; Liu, Meilin

2015-01-13

Embodiments of the present disclosure include chemical compositions, structures, anodes, cathodes, electrolytes for solid oxide fuel cells, solid oxide fuel cells, fuel cells, fuel cell membranes, separation membranes, catalytic membranes, sensors, coatings for electrolytes, electrodes, membranes, and catalysts, and the like, are disclosed.

Calculating the Bending Modulus for Multicomponent Lipid Membranes in Different Thermodynamic Phases

PubMed Central

2013-01-01

We establish a computational approach to extract the bending modulus, KC, for lipid membranes from relatively small-scale molecular simulations. Fluctuations in the splay of individual pairs of lipids faithfully inform on KC in multicomponent membranes over a large range of rigidities in different thermodynamic phases. Predictions are validated by experiments even where the standard spectral analysis-based methods fail. The local nature of this method potentially allows its extension to calculations of KC in protein-laden membranes. PMID:24039553

Grafted functional groups on expanded tetrafluoroethylene (ePTFE) support for fuel cell and water transport membranes

DOEpatents

Fuller, Timothy J.; Jiang, Ruichun

2017-01-24

A method for forming a modified solid polymer includes a step of contacting a solid fluorinated polymer with a sodium sodium-naphthalenide solution to form a treated fluorinated solid polymer. The treated fluorinated solid polymer is contacted with carbon dioxide, sulfur dioxide, or sulfur trioxide to form a solid grafted fluorinated polymer. Characteristically, the grafted fluorinated polymer includes appended CO.sub.2H or SO.sub.2H or SO.sub.3H groups. The solid grafted fluorinated polymer is advantageously incorporated into a fuel cell as part of the ion-conducting membrane or a water transport membrane in a humidifier.

Composite Polymer-Garnet Solid State Electrolytes

NASA Astrophysics Data System (ADS)

Villa, Andres; Oduncu, Muhammed R.; Scofield, Gregory D.; Marinero, Ernesto E.; Forbey, Scott

Solid-state electrolytes provide a potential solution to the safety and reliability issues of Li-ion batteries. We have synthesized cubic-phase Li7-xLa3Zr2-xBixO12 compounds utilizing inexpensive, scalable Sol-gel synthesis and obtained ionic conductivities 1.2 x 10-4 S/cm at RT in not-fully densified pellets. In this work we report on the fabrication of composite polymer-garnet ceramic particle electrolytes to produce flexible membranes that can be integrated with standard battery electrodes without the need for a separator. As a first step we incorporated the ceramic particles into polyethylene oxide polymers (PEO) to form flexible membranes. Early results are encouraging yielding ionic conductivity values 1.0 x 10-5 S/cm at RT. To increment the conductivity in the membranes, we are optimizing amongst other: the ceramic particle size distribution and weight load, the polymer molecular weight and chemical composition and the solvated Li-salt composition and content. Unhindered ion transport across interfaces between the composites and the battery electrode materials is paramount for battery performance. To this end, we are investigating the effect of interface morphology, its atomic composition and exploring novel electrode structures that facilitate ionic transport.

Synthesis of an un-supported, high-flow ZSM-22 zeolite membrane

DOEpatents

Thoma, Steven G [Albuquerque, NM; Nenoff, Tina M [Albuquerque, NM

2006-10-10

Novel methods for synthesizing wholly un-supported, high-flow catalytic membranes consisting of 100% crystalline ZSM-22 crystals with no binder phase, having sufficient porosity to allow high Weight Hourly Space Velocities of feedstock to pass through without generating back pressure. The ZSM-22 membranes perform favorably to existing bulk ZSM-22 catalysts (e.g., via 1-butene conversion and selectivity). The method of membrane synthesis, based on Vapor Phase Transport, allows free-standing, binder-less membranes to be fabricated in varied geometries and sizes so that membranes can be tailor-made for particular geometries applications. The ZSM-22 precursor gel may be consolidated into a semi-cohesive body prior to vapor phase crystallization, for example, by uniaxial pressing. These crystalline membranes may be modified by ion exchange, pore ion exchange, framework exchange, synthesis modification techniques to incorporate other elements into the framework, such as K, H, Mg, Zn, V, Ga, and Pt.

Feed gas contaminant removal in ion transport membrane systems

DOEpatents

Underwood, Richard Paul [Allentown, PA; Makitka, III, Alexander; Carolan, Michael Francis [Allentown, PA

2012-04-03

An oxygen ion transport membrane process wherein a heated oxygen-containing gas having one or more contaminants is contacted with a reactive solid material to remove the one or more contaminants. The reactive solid material is provided as a deposit on a support. The one or more contaminant compounds in the heated oxygen-containing gas react with the reactive solid material. The contaminant-depleted oxygen-containing gas is contacted with a membrane, and oxygen is transported through the membrane to provide transported oxygen.

The Thermodynamics of General and Local Anesthesia

PubMed Central

Græsbøll, Kaare; Sasse-Middelhoff, Henrike; Heimburg, Thomas

2014-01-01

General anesthetics are known to cause depression of the freezing point of transitions in biomembranes. This is a consequence of ideal mixing of the anesthetic drugs in the membrane fluid phase and exclusion from the solid phase. Such a generic law provides physical justification of the famous Meyer-Overton rule. We show here that general anesthetics, barbiturates, and local anesthetics all display the same effect on melting transitions. Their effect is reversed by hydrostatic pressure. Thus, the thermodynamic behavior of local anesthetics is very similar to that of general anesthetics. We present a detailed thermodynamic analysis of heat capacity profiles of membranes in the presence of anesthetics. Using this analysis, we are able to describe experimentally observed calorimetric profiles and predict the anesthetic features of arbitrary molecules. In addition, we discuss the thermodynamic origin of the cutoff effect of long-chain alcohols and the additivity of the effect of general and local anesthetics. PMID:24853743

The Thermodynamics of General and Local Anesthesia

NASA Astrophysics Data System (ADS)

Græsbøll, Kaare; Sasse-Middelhoff, Henrike; Heimburg, Thomas

2014-05-01

General anesthetics are known to cause depression of the freezing point of transitions in biomembranes. This is a consequence of ideal mixing of the anesthetic drugs in the membrane fluid phase and exclusion from the solid phase. Such a generic law provides physical justification of the famous Meyer-Overton rule. We show here that general anesthetics, barbiturates and local anesthetics all display the same effect on melting transitions. Their effect is reversed by hydrostatic pressure. Thus, the thermodynamic behavior of local anesthetics is very similar to that of general anesthetics. We present a detailed thermodynamic analysis of heat capacity profiles of membranes in the presence of anesthetics. This analysis is able to describe experimentally observed calorimetric profiles and permits prediction of the anesthetic features of arbitrary molecules. In addition, we discuss the thermodynamic origin of the cutoff-effect of long-chain alcohols and the additivity of the effect of general and local anesthetics.

A review on solid phase extraction of actinides and lanthanides with amide based extractants.

PubMed

Ansari, Seraj A; Mohapatra, Prasanta K

2017-05-26

Solid phase extraction is gaining attention from separation scientists due to its high chromatographic utility. Though both grafted and impregnated forms of solid phase extraction resins are popular, the later is easy to make by impregnating a given organic extractant on to an inert solid support. Solid phase extraction on an impregnated support, also known as extraction chromatography, combines the advantages of liquid-liquid extraction and the ion exchange chromatography methods. On the flip side, the impregnated extraction chromatographic resins are less stable against leaching out of the organic extractant from the pores of the support material. Grafted resins, on the other hand, have a higher stability, which allows their prolong use. The goal of this article is a brief literature review on reported actinide and lanthanide separation methods based on solid phase extractants of both the types, i.e., (i) ligand impregnation on the solid support or (ii) ligand functionalized polymers (chemically bonded resins). Though the literature survey reveals an enormous volume of studies on the extraction chromatographic separation of actinides and lanthanides using several extractants, the focus of the present article is limited to the work carried out with amide based ligands, viz. monoamides, diamides and diglycolamides. The emphasis will be on reported applied experimental results rather than on data pertaining fundamental metal complexation. Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of colloidal and dissolved silver in water samples using colorimetric solid-phase extraction.

PubMed

Hill, April A; Lipert, Robert J; Porter, Marc D

2010-03-15

The increase in bacterial resistance to antibiotics has led to resurgence in the use of silver as a biocidal agent in applications ranging from washing machine additives to the drinking water treatment system on the International Space Station (ISS). However, growing concerns about the possible toxicity of colloidal silver to bacteria, aquatic organisms and humans have led to recently issued regulations by the US EPA and FDA regarding the usage of silver. As part of an ongoing project, we have developed a rapid, simple method for determining total silver, both ionic (silver(I)) and colloidal, in 0.1-1mg/L aqueous samples, which spans the ISS potable water target of 0.3-0.5mg/L (total silver) and meets the US EPA limit of 0.1mg/L in drinking water. The method is based on colorimetric solid-phase extraction (C-SPE) and involves the extraction of silver(I) from water samples by passage through a solid-phase membrane impregnated with the colorimetric reagent DMABR (5-[4-(dimethylamino)benzylidene]rhodanine). Silver(I) exhaustively reacts with impregnated DMABR to form a colored compound, which is quantified using a handheld diffuse reflectance spectrophotometer. Total silver is determined by first passing the sample through a cartridge containing Oxone, which exhaustively oxidizes colloidal silver to dissolved silver(I). The method, which takes less than 2 min to complete and requires only approximately 1 mL of sample, has been validated through a series of tests, including a comparison with the ICP-MS analysis of a water sample from ISS that contained both silver(I) and colloidal silver. Potential earth-bound applications are also briefly discussed. Copyright (c) 2009 Elsevier B.V. All rights reserved.

Fuel spill identification using solid-phase extraction and solid-phase microextraction. 1. Aviation turbine fuels.

PubMed

Lavine, B K; Brzozowski, D M; Ritter, J; Moores, A J; Mayfield, H T

2001-12-01

The water-soluble fraction of aviation jet fuels is examined using solid-phase extraction and solid-phase microextraction. Gas chromatographic profiles of solid-phase extracts and solid-phase microextracts of the water-soluble fraction of kerosene- and nonkerosene-based jet fuels reveal that each jet fuel possesses a unique profile. Pattern recognition analysis reveals fingerprint patterns within the data characteristic of fuel type. By using a novel genetic algorithm (GA) that emulates human pattern recognition through machine learning, it is possible to identify features characteristic of the chromatographic profile of each fuel class. The pattern recognition GA identifies a set of features that optimize the separation of the fuel classes in a plot of the two largest principal components of the data. Because principal components maximize variance, the bulk of the information encoded by the selected features is primarily about the differences between the fuel classes.

Grape tannin catechin and ethanol fluidify oral membrane mimics containing moderate amounts of cholesterol: Implications on wine tasting?

PubMed

Furlan, Aurélien L; Saad, Ahmad; Dufourc, Erick J; Géan, Julie

2016-11-01

Wine tasting results in interactions of tannin-ethanol solutions with proteins and lipids of the oral cavity. Among the various feelings perceived during tasting, astringency and bitterness most probably result in binding events with saliva proteins, lipids and receptors. In this work, we monitored the conjugated effect of the grape polyphenol catechin and ethanol on lipid membranes mimicking the different degrees of keratinization of oral cavity surfaces by varying the amount of cholesterol present in membranes. Both catechin and ethanol fluidify the membranes as evidenced by solid-state 2 H NMR of perdeuterated lipids. The effect is however depending on the cholesterol proportion and may be very important and cumulative in the absence of cholesterol or presence of 18 mol % cholesterol. For 40 mol % cholesterol, mimicking highly keratinized membranes, both ethanol and catechin can no longer affect membrane dynamics. These observations can be accounted for by phase diagrams of lipid-cholesterol mixtures and the role played by membrane defects for insertion of tannins and ethanol when several phases coexist. These findings suggest that the behavior of oral membranes in contact with wine should be different depending of their cholesterol content. Astringency and bitterness could be then affected; the former because of a potential competition between the tannin-lipid and the tannin-saliva protein interaction, and the latter because of a possible fluidity modification of membranes containing taste receptors. The lipids that have been up to now weakly considered in oenology may be become a new actor in the issue of wine tasting. Copyright © 2016 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

Hydrogen storage systems based on magnesium hydride: from laboratory tests to fuel cell integration

NASA Astrophysics Data System (ADS)

de Rango, P.; Marty, P.; Fruchart, D.

2016-02-01

The paper reviews the state of the art of hydrogen storage systems based on magnesium hydride, emphasizing the role of thermal management, whose effectiveness depends on the effective thermal conductivity of the hydride, but also depends of other limiting factors such as wall contact resistance and convective exchanges with the heat transfer fluid. For daily cycles, the use of phase change material to store the heat of reaction appears to be the most effective solution. The integration with fuel cells (1 kWe proton exchange membrane fuel cell and solid oxide fuel cell) highlights the dynamic behaviour of these systems, which is related to the thermodynamic properties of MgH2. This allows for "self-adaptive" systems that do not require control of the hydrogen flow rate at the inlet of the fuel cell.

Changes in the physical properties of the dynamic layer and its correlation with permeate quality in a self-forming dynamic membrane bioreactor.

PubMed

Guan, Dao; Dai, Ji; Watanabe, Yoshimasa; Chen, Guanghao

2018-09-01

The self-forming dynamic membrane bioreactor (SFDMBR) is a biological wastewater treatment technology based on the conventional membrane bioreactor (MBR) with membrane material modification to a large pore size (30-100 μm). This modification requires a dynamic layer formed by activated sludge to provide effective filtration function for high-quality permeate production. The properties of the dynamic layer are therefore important for permeate quality in SFDMBRs. The interaction between the structure of the dynamic layer and the performance of SFDMBRs is little known but understandably complex. To elucidate the interaction, a lab-scale SFDMBR system coupled with a nylon woven mesh as the supporting material was operated. After development of a mature dynamic layer, excellent solid-liquid separation was achieved, as evidenced by a low permeate turbidity of less than 2 NTU. The permeate turbidity stayed below this level for nearly 80 days. In the fouling phase, the dynamic layer was compressed with an increase in the trans-membrane pressure and the quality of the permeate kept deteriorating until the turbidity exceeded 10 NTU. The investigation revealed that the majority of permeate particles were dissociated from the dynamic layer on the back surface of the supporting material, which is caused by the compression, breakdown, and dissociation of the dynamic layer. This phenomenon was observed directly in experiment instead of model prediction or conjecture for the first time. Copyright © 2018 Elsevier Ltd. All rights reserved.

Shuttle: forever young?

PubMed

Sietzen, Frank

2002-01-01

NASA has started a 4-phase program of upgrades designed to increase safety and extend use of the space shuttles through the year 2020. Phase I is aimed at improving vehicle safety and supporting the space station. Phase II is aimed at combating obsolescence and includes a checkout launch and control system and protection from micrometeoroids and orbital debris. Phase III is designed to expand or enhance the capabilities of the shuttle and includes development of an auxiliary power unit, avionics, a channel-wall nozzle, extended nose landing gear, long-life fuel cells, a nontoxic orbital maneuvering system/reaction control system, and a water membrane evaporator. Phase IV is aimed at design of system changes that would alter the shuttle mold line and configuration; projects include a five-segment solid rocket booster, liquid flyback boosters, and a crew escape module.

Full Eulerian simulations of biconcave neo-Hookean particles in a Poiseuille flow

NASA Astrophysics Data System (ADS)

Sugiyama, Kazuyasu; , Satoshi, II; Takeuchi, Shintaro; Takagi, Shu; Matsumoto, Yoichiro

2010-03-01

For a given initial configuration of a multi-component geometry represented by voxel-based data on a fixed Cartesian mesh, a full Eulerian finite difference method facilitates solution of dynamic interaction problems between Newtonian fluid and hyperelastic material. The solid volume fraction, and the left Cauchy-Green deformation tensor are temporally updated on the Eulerian frame, respectively, to distinguish the fluid and solid phases, and to describe the solid deformation. The simulation method is applied to two- and three-dimensional motions of two biconcave neo-Hookean particles in a Poiseuille flow. Similar to the numerical study on the red blood cell motion in a circular pipe (Gong et al. in J Biomech Eng 131:074504, 2009), in which Skalak’s constitutive laws of the membrane are considered, the deformation, the relative position and orientation of a pair of particles are strongly dependent upon the initial configuration. The increase in the apparent viscosity is dependent upon the developed arrangement of the particles. The present Eulerian approach is demonstrated that it has the potential to be easily extended to larger system problems involving a large number of particles of complicated geometries.

Reactive Capping Mat Development and Evaluation for Sequestering Contaminants in Sediments

DTIC Science & Technology

2011-08-01

semi-permeable membrane devices (SPMDs) and solid phase micro-extraction (SPME) fibers . Peepers are expression samplers constructed of...in fish organs. The SPME fibers are coated with a liquid polymer that allows organic contaminants to establish equilibria between the fiber and the...between 10 and 20 cm of 300/200 µm polydimethylsiloxan (PMDS) fiber (Fiberguide) per replicate sample. Fibers were deployed at 10 cm lengths in a

A Novel MicroElectroMechanical System (MEMS) Device for Passive Sampling of Hydrophobic Compounds

DTIC Science & Technology

2011-05-01

bioavailability  Samplers are removed, extracted for CoC, analyzed ▬ For organics: solid phase micro extraction ( SPME ) fibers, semi- permeable membrane...devices (SPMD), polyoxymethylene (POM) ▬ For metals: diffuse gradients in thin films (DGT) SPME fiber ESTCP project, Reible and Lotufo Applications to...Predict Bioaccumulation You et al. 2006, EST, 40: 6348 SPME concentrations were predictive of tissue concentrations of PCBs in field-contaminated

An all-solid-state reference electrode based on the layer-by-layer polymer coating.

PubMed

Kwon, Nak-Hyun; Lee, Kyung-Sun; Won, Mi-Sook; Shim, Yoon-Bo

2007-09-01

A solid-state reference electrode (SSRE) was fabricated by layering a silicone rubber (SR) film containing KCl on an AgCl surface, then a perfluorinated ionomer film, and finally a polyurethane-based membrane containing an ionophore, a lipophilic ionic additive, and a plasticizer, respectively. The addition of SiCl4 to the polyurethane-based membrane layer enhanced the strength of the membrane in an aqueous solution. The morphologies of the membranes were studied separately by SEM. The fabrication of the Ag/AgCl electrode through this layer-by-layer polymer coating improved the electrode stability enormously. In addition, the potential drift of the SSRE according to the pH of the medium was minimized by introducing a H+-ion-selective ionophore (tridodecylamine; TDDA) into the outmost polymer membrane. The cyclic voltammetric and potentiometric responses using the SSRE and a conventional reference electrode, respectively, were consistent. The SSRE exhibited little potential variation even in the case of the addition of very high concentrations of various salts, such as Na salicylate, LiCl, KCl, CaCl2, MgCl2, KNO3, NaCl, and NaHCO3. The practicability of the proposed SSRE was tested for the determination of blood pH and pCO2 in a flow cell system. The SSRE fabricated in the present study was stable over two years.

Comparison of semipermeable membrane device (SPMD) and large-volume solid-phase extraction techniques to measure water concentrations of 4,4'-DDT, 4,4'-DDE, and 4,4'-DDD in Lake Chelan, Washington.

PubMed

Ellis, Steven G; Booij, Kees; Kaputa, Mike

2008-07-01

Semipermeable membrane devices (SPMDs) spiked with the performance reference compound PCB29 were deployed 6.1 m above the sediments of Lake Chelan, Washington, for a period of 27 d, to estimate the dissolved concentrations of 4,4'-DDT, 4,4'-DDE, and 4,4'-DDD. Water concentrations were estimated using methods proposed in 2002 and newer equations published in 2006 to determine how the application of the newer equations affects historical SPMD data that used the older method. The estimated concentrations of DDD, DDE, and DDD calculated using the older method were 1.5-2.9 times higher than the newer method. SPMD estimates from both methods were also compared to dissolved and particulate DDT concentrations measured directly by processing large volumes of water through a large-volume solid-phase extraction device (Infiltrex 300). SPMD estimates of DDD+DDE+DDT (SigmaDDT) using the older and newer methods were lower than Infiltrex concentrations by factors of 1.1 and 2.3, respectively. All measurements of DDT were below the Washington State water quality standards for the protection of human health (0.59 ng l(-1)) and aquatic life (1.0 ng l(-1)).

Hierarchical multiscale hyperporous block copolymer membranes via tunable dual-phase separation

PubMed Central

Yoo, Seungmin; Kim, Jung-Hwan; Shin, Myoungsoo; Park, Hyungmin; Kim, Jeong-Hoon; Lee, Sang-Young; Park, Soojin

2015-01-01

The rational design and realization of revolutionary porous structures have been long-standing challenges in membrane science. We demonstrate a new class of amphiphilic polystyrene-block-poly(4-vinylpyridine) block copolymer (BCP)–based porous membranes featuring hierarchical multiscale hyperporous structures. The introduction of surface energy–modifying agents and the control of major phase separation parameters (such as nonsolvent polarity and solvent drying time) enable tunable dual-phase separation of BCPs, eventually leading to macro/nanoscale porous structures and chemical functionalities far beyond those accessible with conventional approaches. Application of this BCP membrane to a lithium-ion battery separator affords exceptional improvement in electrochemical performance. The dual-phase separation–driven macro/nanopore construction strategy, owing to its simplicity and tunability, is expected to be readily applicable to a rich variety of membrane fields including molecular separation, water purification, and energy-related devices. PMID:26601212

New porous monolithic membranes based on supported ionic liquid-like phases for oil/water separation and homogenous catalyst immobilisation.

PubMed

Porcar, Raúl; Nuevo, Daniel; García-Verdugo, Eduardo; Lozano, Pedro; Sanchez-Marcano, José; Burguete, M Isabel; Luis, Santiago V

2018-03-07

Porous monolithic advanced functional materials based on supported ionic liquid-like phase (SILLP) systems were used for the preparation of oleophilic and hydrophobic cylindrical membranes and successfully tested as eco-friendly and safe systems for oil/water separation and for the continuous integration of catalytic and separation processes in an aqueous-organic biphasic reaction system.

Malignant hyperthermia and calcium-induced heat production.

PubMed

Ueda, I; Shinoda, F; Kamaya, H; Krishna, P R

1994-05-01

The abnormal increase in intracellular Ca++ in malignant hyperthermia (MH) is well documented, but the link between the increased Ca++ concentration and high temperature remains speculative. We investigated the possibility that the Ca(++)-induced change in the state of cell membranes may contribute to the temperature elevation. Calcium ion transforms phospholipid membranes from the fluid to solid state. This is analogous to the freezing of water, and liberates latent heat. Differential titration calorimetry (DTC) measures heat production or absorption during ligand binding to macromolecules. When CaCl2 solution was added to anionic dimyristoylphosphatidic acid (DMPA) and dimyristoylphosphatidylglycerol (DMPG) vesicle membranes in incremental doses, DTC showed that the heat production suddenly increased when the Ca++ concentration exceeded about 120 microM. At this Ca++ concentration range, these lipid membranes underwent phase transition. The latent heat of transition was measured by differential scanning calorimetry (DSC). The values were 7.1 +/- 0.7 (SD, n = 4) kcal.mol-1 of DMPA and 6.8 +/- 0.7 (SD, n = 4) kcal.mol-1 of DMPG. The study shows that Ca++ produces heat when bound to lipid membranes. We are not proposing, however, that this is the sole source of heat. We contend that the lipid phase transition is one of the heat sources and it may trigger a hypermetabolic state by elevating the temperature of cell membranes. Because Ca++ is implicated as the second messenger in signal transduction, multiple systems may be involved. More studies are needed to clarify how Ca++ increases body temperature.

Toward ambient temperature operation with all-solid-state lithium metal batteries with a sp3 boron-based solid single ion conducting polymer electrolyte

NASA Astrophysics Data System (ADS)

Zhang, Yunfeng; Cai, Weiwei; Rohan, Rupesh; Pan, Meize; Liu, Yuan; Liu, Xupo; Li, Cuicui; Sun, Yubao; Cheng, Hansong

2016-02-01

The ionic conductivity decay problem of poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) when increase the lithium salt of the SPEs up to high concentration is here functionally overcome by the incorporation of a charge delocalized sp3 boron based single ion conducting polymer electrolyte (SIPE) with poly(ethylene oxide) to fabricate solid-state sp3 boron based SIPE membranes (S-BSMs). By characterizations, particularly differential scanning calorimeter (DSC) and ionic conductivity studies, the fabricated S-BSMs showed decreased melting points and increased ionic conductivity as steadily increase the content of sp3 boron based SIPE, which significantly improved the low temperature performance of the all-solid-state lithium batteries. The fabricated Li | S-BSMs | LiFePO4 cells exhibit highly electrochemical stability and excellent cycling at temperature below melting point of PEO, which has never been reported so far for SIPEs based all-solid-state lithium batteries.

Environmental Assessment for Implementation of Expanded Bird-Aircraft Strike Hazard (BASH) Program for Moody Air Force Base and Private and Public Lands Surrounding Moody Air Force Base, Georgia

DTIC Science & Technology

2003-09-01

values are not expected to be significantly impacted by any of the alternatives analyzed: soils , geology, minerals, water quality/quantity, flood...pesticides on eggshell thickness, rather than direct mortality events (GWF, 2003). The proposed action does not involve the destruction of nesting

Review of Fuel Cell Technologies for Military Land Vehicles

DTIC Science & Technology

2014-09-01

fuel cell technologies for APUs are Proton Exchange Membrane Fuel Cells ( PEMFC ), direct methanol fuel cells and Solid Oxide Fuel Cells (SOFC). The...6 4.2 Proton Exchange Membrane Fuel Cells ( PEMFC ...OEM Original Equipment Manufacturer PEM Proton Exchange Membrane PEMFC Proton Exchange Membrane Fuel Cell SOFC Solid Oxide Fuel Cell TRL Technical

Membrane hydrophone phase characteristics through nonlinear acoustics measurements.

PubMed

Bloomfield, Philip E; Gandhi, Gaurav; Lewin, Peter A

2011-11-01

This work considers the need for both the amplitude and phase to fully characterize polyvinylidene fluoride (PVDF) membrane hydrophones and presents a comprehensive discussion of the nonlinear acoustic measurements utilized to extract the phase information and the experimental results taken with two widely used PVDF membrane hydrophones up to 100 MHz. A semi-empirical computer model utilized the hyperbolic propagation operator to predict the nonlinear pressure field and provide the complex frequency response of the corresponding source transducer. The PVDF hydrophone phase characteristics, which were obtained directly from the difference between the computer-modeled nonlinear field simulation and the corresponding measured harmonic frequency phase values, agree to within 10% with the phase predictions obtained from receive-transfer-function simulations based on software modeling of the membrane's physical properties. Cable loading effects and membrane hydrophone resonances were distinguished and identified through a series of impedance measurements and receive transfer function simulations on the hydrophones including their hard-wired coaxial cables. The results obtained indicate that the PVDF membrane hydrophone's phase versus frequency plot exhibits oscillations about a monotonically decreasing line. The maxima and minima inflection point slopes occur at the membrane thickness resonances and antiresonances, respectively. A cable resonance was seen at 100 MHz for the hydrophone with a 1-m cable attached, but not seen for the hydrophone with a shorter 0.65-m cable.

Structure and interactions in biomaterials based on membrane-biopolymer self-assembly

NASA Astrophysics Data System (ADS)

Koltover, Ilya

Physical and chemical properties of artificial pure lipid membranes have been extensively studied during the last two decades and are relatively well understood. However, most real membrane systems of biological and biotechnological importance incorporate macromolecules either embedded into the membranes or absorbed onto their surfaces. We have investigated three classes of self-assembled membrane-biopolymer biomaterials: (i) Structure, interactions and stability of the two-dimensional crystals of the integral membrane protein bacteriorhodopsin (bR). We have conducted a synchrotron x-ray diffraction study of oriented bR multilayers. The important findings were as follows: (1) the protein 2D lattice exhibited diffraction patterns characteristic of a 2D solid with power-law decay of in-plane positional correlations, which allowed to measure the elastic constants of protein crystal; (2) The crystal melting temperature was a function of the multilayer hydration, reflecting the effect of inter-membrane repulsion on the stability of protein lattice; (3) Preparation of nearly perfect (mosaicity < 0.04° ) multilayers of fused bR membranes permitted, for the first time, application of powerful interface-sensitive x-ray scattering techniques to a membrane-protein system. (ii) Interactions between the particles chemically attached or absorbed onto the surfaces of flexible giant phospholipid vesicles. Using video-enhanced light microscopy we have observed a membrane-distortion induced attraction between the particles with the interaction range of the order of particle diameter. Fluid membranes decorated with many particles exhibited: (i) a finite-sized two-dimensional closed packed aggregates and (ii) a one-dimensional ring-like aggregates. (iii) Structure, stability and interactions in the cationic lipid-DNA complexes. Cationic liposomes complexed with DNA are among the most promising synthetic non-viral carriers of DNA vectors currently used in gene therapy applications. We have established that DNA complexes with cationic lipid (DOTAP) and a neutral lipid (DOPC) have a compact multilayer liquid crystalline structure ( L ca ) with DNA intercalated between the lipid bilayers in a periodic 2D smectic phase. Furthermore, a different 2D columnar phase of complexes was found in mixtures with a transfectionen-hancing lipid DOPE. This structure ( HcII ) derived from synchrotron x-ray diffraction consists of DNA coated by cationic lipid monolayers and arranged on a two-dimensional hexagonal lattice. Optical microscopy revealed that the L ca complexes bind stably to anionic vesicles (models of cellular membranes), whereas the more transfectant HcII complexes are unstable, rapidly fusing and releasing DNA upon adhering to anionic vesicles.

Comparison of eggshell surface sanitization technologies and impacts on consumer acceptability.

PubMed

Al-Ajeeli, Morouj N; Taylor, T Matthew; Alvarado, Christine Z; Coufal, Craig D

2016-05-01

Shell eggs can be contaminated with many types of microorganisms, including bacterial pathogens, and thus present a risk for the transmission of foodborne disease to consumers. Currently, most United States egg processors utilize egg washing and sanitization systems to decontaminate surfaces of shell eggs prior to packaging. However, previous research has indicated that current shell egg sanitization technologies employed in the commercial egg industry may not completely eliminate bacteria from the surface of eggshells, and thus alternative egg sanitization technologies with the potential for increased microbial reductions on eggshells should be investigated. The objectives of this study were to compare the antimicrobial efficacy and consumer sensory attributes of industry-available eggshell sanitization methods (chlorine and quaternary ammonium compounds (QAC) applied via spray) to various alternative egg sanitization technologies. Eggs (White Leghorn hens; n=195) were obtained for evaluation of sanitizer-induced reduction in mesophilic aerobic bacteria (n=90) or inoculated Salmonella Enteritidis (SE) reduction (n=105). Sanitizing treatments evaluated in this experiment were: chlorine spray (100 ppm available chlorine), QAC spray (200 ppm), peracetic acid spray (PAA; 135 ppm) alone or in combination with ultraviolet light (UV; 254 nm), and hydrogen peroxide (H2O2; 3.5% solution) spray in combination with UV (H2O2+UV). For enumeration of aerobic bacteria, eggs were sampled at 0, 7, and 14 days of storage at 4°C; surviving SE cells from inoculated eggs were enumerated by differential plating. Sensory trials were conducted to determine consumer liking of scrambled eggs made from eggs sanitized with chlorine, QAC, H2O2+UV, or no treatment (control). The H2O2 and UV treatment resulted in the greatest reductions in eggshell aerobic plate counts compared to other treatments throughout egg storage (P<0.05). All treatments utilized reduced SE below the limit of detection by eggshell rinse. There were no differences in consumers' liking of overall flavor between the 4 treatments evaluated. The application of H2O2+UV treatment to shell eggs represents a novel technology that could have important implications for egg quality and safety preservation. © 2016 Poultry Science Association Inc.

It’s what’s inside that counts: Egg contaminant concentrations are influenced by estimates of egg density, egg volume, and fresh egg mass

USGS Publications Warehouse

Herzog, Mark; Ackerman, Joshua T.; Eagles-Smith, Collin A.; Hartman, Christopher

2016-01-01

In egg contaminant studies, it is necessary to calculate egg contaminant concentrations on a fresh wet weight basis and this requires accurate estimates of egg density and egg volume. We show that the inclusion or exclusion of the eggshell can influence egg contaminant concentrations, and we provide estimates of egg density (both with and without the eggshell) and egg-shape coefficients (used to estimate egg volume from egg morphometrics) for American avocet (Recurvirostra americana), black-necked stilt (Himantopus mexicanus), and Forster’s tern (Sterna forsteri). Egg densities (g/cm3) estimated for whole eggs (1.056 ± 0.003) were higher than egg densities estimated for egg contents (1.024 ± 0.001), and were 1.059 ± 0.001 and 1.025 ± 0.001 for avocets, 1.056 ± 0.001 and 1.023 ± 0.001 for stilts, and 1.053 ± 0.002 and 1.025 ± 0.002 for terns. The egg-shape coefficients for egg volume (K v ) and egg mass (K w ) also differed depending on whether the eggshell was included (K v = 0.491 ± 0.001; K w = 0.518 ± 0.001) or excluded (K v = 0.493 ± 0.001; K w = 0.505 ± 0.001), and varied among species. Although egg contaminant concentrations are rarely meant to include the eggshell, we show that the typical inclusion of the eggshell in egg density and egg volume estimates results in egg contaminant concentrations being underestimated by 6–13 %. Our results demonstrate that the inclusion of the eggshell significantly influences estimates of egg density, egg volume, and fresh egg mass, which leads to egg contaminant concentrations that are biased low. We suggest that egg contaminant concentrations be calculated on a fresh wet weight basis using only internal egg-content densities, volumes, and masses appropriate for the species. For the three waterbirds in our study, these corrected coefficients are 1.024 ± 0.001 for egg density, 0.493 ± 0.001 for K v , and 0.505 ± 0.001 for K w .

Solid state NMR: The essential technology for helical membrane protein structural characterization

PubMed Central

Cross, Timothy A.; Ekanayake, Vindana; Paulino, Joana; Wright, Anna

2014-01-01

NMR spectroscopy of helical membrane proteins has been very challenging on multiple fronts. The expression and purification of these proteins while maintaining functionality has consumed countless graduate student hours. Sample preparations have depended on whether solution or solid-state NMR spectroscopy was to be performed – neither have been easy. In recent years it has become increasingly apparent that membrane mimic environments influence the structural result. Indeed, in these recent years we have rediscovered that Nobel laureate, Christian Anfinsen, did not say that protein structure was exclusively dictated by the amino acid sequence, but rather by the sequence in a given environment (Anfinsen, 1973) [106]. The environment matters, molecular interactions with the membrane environment are significant and many examples of distorted, non-native membrane protein structures have recently been documented in the literature. However, solid-state NMR structures of helical membrane proteins in proteoliposomes and bilayers are proving to be native structures that permit a high resolution characterization of their functional states. Indeed, solid-state NMR is uniquely able to characterize helical membrane protein structures in lipid environments without detergents. Recent progress in expression, purification, reconstitution, sample preparation and in the solid-state NMR spectroscopy of both oriented samples and magic angle spinning samples has demonstrated that helical membrane protein structures can be achieved in a timely fashion. Indeed, this is a spectacular opportunity for the NMR community to have a major impact on biomedical research through the solid-state NMR spectroscopy of these proteins. PMID:24412099

Solid state NMR: The essential technology for helical membrane protein structural characterization

NASA Astrophysics Data System (ADS)

Cross, Timothy A.; Ekanayake, Vindana; Paulino, Joana; Wright, Anna

2014-02-01

NMR spectroscopy of helical membrane proteins has been very challenging on multiple fronts. The expression and purification of these proteins while maintaining functionality has consumed countless graduate student hours. Sample preparations have depended on whether solution or solid-state NMR spectroscopy was to be performed - neither have been easy. In recent years it has become increasingly apparent that membrane mimic environments influence the structural result. Indeed, in these recent years we have rediscovered that Nobel laureate, Christian Anfinsen, did not say that protein structure was exclusively dictated by the amino acid sequence, but rather by the sequence in a given environment (Anfinsen, 1973) [106]. The environment matters, molecular interactions with the membrane environment are significant and many examples of distorted, non-native membrane protein structures have recently been documented in the literature. However, solid-state NMR structures of helical membrane proteins in proteoliposomes and bilayers are proving to be native structures that permit a high resolution characterization of their functional states. Indeed, solid-state NMR is uniquely able to characterize helical membrane protein structures in lipid environments without detergents. Recent progress in expression, purification, reconstitution, sample preparation and in the solid-state NMR spectroscopy of both oriented samples and magic angle spinning samples has demonstrated that helical membrane protein structures can be achieved in a timely fashion. Indeed, this is a spectacular opportunity for the NMR community to have a major impact on biomedical research through the solid-state NMR spectroscopy of these proteins.

Three-phase boundary length in solid-oxide fuel cells: A mathematical model

NASA Astrophysics Data System (ADS)

Janardhanan, Vinod M.; Heuveline, Vincent; Deutschmann, Olaf

A mathematical model to calculate the volume specific three-phase boundary length in the porous composite electrodes of solid-oxide fuel cell is presented. The model is exclusively based on geometrical considerations accounting for porosity, particle diameter, particle size distribution, and solids phase distribution. Results are presented for uniform particle size distribution as well as for non-uniform particle size distribution.

Selective isolation of hydrophobin SC3 by solid-phase extraction with polytetrafluoroethylene microparticles and subsequent mass spectrometric analysis.

PubMed

Kupčík, Rudolf; Zelená, Miroslava; Řehulka, Pavel; Bílková, Zuzana; Česlová, Lenka

2016-02-01

Hydrophobins are small proteins that play a role in a number of processes during the filamentous fungi growth and development. These proteins are characterized by the self-assembly of their molecules into an amphipathic membrane at hydrophilic-hydrophobic interfaces. Isolation and purification of hydrophobins generally present a challenge in their analysis. Hydrophobin SC3 from Schizophyllum commune was selected as a representative of class I hydrophobins in this work. A novel procedure for selective and effective isolation of hydrophobin SC3 based on solid-phase extraction with polytetrafluoroethylene microparticles loaded in a small self-made microcolumn is reported. The tailored binding of hydrophobins to polytetrafluoroethylene followed by harsh elution conditions resulted in a highly specific isolation of hydrophobin SC3 from the model mixture of ten proteins. The presented isolation protocol can have a positive impact on the analysis and utilization of these proteins including all class I hydrophobins. Hydrophobin SC3 was further subjected to reduction of its highly stable disulfide bonds and to chymotryptic digestion followed by mass spectrometric analysis. The isolation and digestion protocols presented in this work make the analysis of these highly hydrophobic and compact proteins possible. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rapid electron exchange between surface-exposed bacterial cytochromes and Fe(III) minerals

PubMed Central

White, Gaye F.; Shi, Zhi; Shi, Liang; Wang, Zheming; Dohnalkova, Alice C.; Marshall, Matthew J.; Fredrickson, James K.; Zachara, John M.; Butt, Julea N.; Richardson, David J.; Clarke, Thomas A.

2013-01-01

The mineral-respiring bacterium Shewanella oneidensis uses a protein complex, MtrCAB, composed of two decaheme cytochromes, MtrC and MtrA, brought together inside a transmembrane porin, MtrB, to transport electrons across the outer membrane to a variety of mineral-based electron acceptors. A proteoliposome system containing a pool of internalized electron carriers was used to investigate how the topology of the MtrCAB complex relates to its ability to transport electrons across a lipid bilayer to externally located Fe(III) oxides. With MtrA facing the interior and MtrC exposed on the outer surface of the phospholipid bilayer, the established in vivo orientation, electron transfer from the interior electron carrier pool through MtrCAB to solid-phase Fe(III) oxides was demonstrated. The rates were 103 times higher than those reported for reduction of goethite, hematite, and lepidocrocite by S. oneidensis, and the order of the reaction rates was consistent with those observed in S. oneidensis cultures. In contrast, established rates for single turnover reactions between purified MtrC and Fe(III) oxides were 103 times lower. By providing a continuous flow of electrons, the proteoliposome experiments demonstrate that conduction through MtrCAB directly to Fe(III) oxides is sufficient to support in vivo, anaerobic, solid-phase iron respiration. PMID:23538304

Magnesium Recycling of Partially Oxidized, Mixed Magnesium-Aluminum Scrap Through Combined Refining and Solid Oxide Membrane (SOM) Electrolysis Processes

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

Guan, Xiaofei; Zink, Peter; Pal, Uday

2012-03-11

Pure magnesium (Mg) is recycled from 19g of partially oxidized 50.5wt.%Mg-Aluminum (Al) alloy. During the refining process, potentiodynamic scans (PDS) were performed to determine the electrorefining potential for magnesium. The PDS show that the electrorefining potential increases over time as the Mg content inside the Mg-Al scrap decreases. Up to 100% percent of magnesium is refined from the Mg-Al scrap by a novel refining process of dissolving magnesium and its oxide into a flux followed by vapor phase removal of dissolved magnesium and subsequently condensing the magnesium vapors in a separate condenser. The solid oxide membrane (SOM) electrolysis process ismore » employed in the refining system to enable additional recycling of magnesium from magnesium oxide (MgO) in the partially oxidized Mg-Al scrap. The combination of the refining and SOM processes yields 7.4g of pure magnesium; could not collect and weigh all of the magnesium recovered.« less

Automation of static and dynamic non-dispersive liquid phase microextraction. Part 2: Approaches based on impregnated membranes and porous supports.

PubMed

Alexovič, Michal; Horstkotte, Burkhard; Solich, Petr; Sabo, Ján

2016-02-11

A critical overview on automation of modern liquid phase microextraction (LPME) approaches based on the liquid impregnation of porous sorbents and membranes is presented. It is the continuation of part 1, in which non-dispersive LPME techniques based on the use of the extraction phase (EP) in the form of drop, plug, film, or microflow have been surveyed. Compared to the approaches described in part 1, porous materials provide an improved support for the EP. Simultaneously they allow to enlarge its contact surface and to reduce the risk of loss by incident flow or by components of surrounding matrix. Solvent-impregnated membranes or hollow fibres are further ideally suited for analyte extraction with simultaneous or subsequent back-extraction. Their use can therefore improve the procedure robustness and reproducibility as well as it "opens the door" to the new operation modes and fields of application. However, additional work and time are required for membrane replacement and renewed impregnation. Automation of porous support-based and membrane-based approaches plays an important role in the achievement of better reliability, rapidness, and reproducibility compared to manual assays. Automated renewal of the extraction solvent and coupling of sample pretreatment with the detection instrumentation can be named as examples. The different LPME methodologies using impregnated membranes and porous supports for the extraction phase and the different strategies of their automation, and their analytical applications are comprehensively described and discussed in this part. Finally, an outlook on future demands and perspectives of LPME techniques from both parts as a promising area in the field of sample pretreatment is given. Copyright © 2015 Elsevier B.V. All rights reserved.

Review of online coupling of sample preparation techniques with liquid chromatography.

PubMed

Pan, Jialiang; Zhang, Chengjiang; Zhang, Zhuomin; Li, Gongke

2014-03-07

Sample preparation is still considered as the bottleneck of the whole analytical procedure, and efforts has been conducted towards the automation, improvement of sensitivity and accuracy, and low comsuption of organic solvents. Development of online sample preparation techniques (SP) coupled with liquid chromatography (LC) is a promising way to achieve these goals, which has attracted great attention. This article reviews the recent advances on the online SP-LC techniques. Various online SP techniques have been described and summarized, including solid-phase-based extraction, liquid-phase-based extraction assisted with membrane, microwave assisted extraction, ultrasonic assisted extraction, accelerated solvent extraction and supercritical fluids extraction. Specially, the coupling approaches of online SP-LC systems and the corresponding interfaces have been discussed and reviewed in detail, such as online injector, autosampler combined with transport unit, desorption chamber and column switching. Typical applications of the online SP-LC techniques have been summarized. Then the problems and expected trends in this field are attempted to be discussed and proposed in order to encourage the further development of online SP-LC techniques. Copyright © 2014 Elsevier B.V. All rights reserved.

Solid-Contact pH Sensor without CO2 Interference with a Superhydrophobic PEDOT-C14 as Solid Contact: The Ultimate "Water Layer" Test.

PubMed

Guzinski, Marcin; Jarvis, Jennifer M; D'Orazio, Paul; Izadyar, Anahita; Pendley, Bradford D; Lindner, Ernő

2017-08-15

The aim of this study was to find a conducting polymer-based solid contact (SC) for ion-selective electrodes (ISEs) that could become the ultimate, generally applicable SC, which in combination with all kinds of ion-selective membranes (ISMs) would match the performance characteristics of conventional ISEs. We present data collected with electrodes utilizing PEDOT-C 14 , a highly hydrophobic derivative of poly(3,4-ethylenedioxythiophene), PEDOT, as SC and compare its performance characteristics with PEDOT-based SC ISEs. PEDOT-C 14 has not been used in SC ISEs previously. The PEDOT-C 14 -based solid contact (SC) ion-selective electrodes (ISEs) (H + , K + , and Na + ) have outstanding performance characteristics (theoretical response slope, short equilibration time, excellent potential stability, etc.). Most importantly, PEDOT-C 14 -based SC pH sensors have no CO 2 interference, an essential pH sensors property when aimed for whole-blood analysis. The superhydrophobic properties (water contact angle: 136 ± 5°) of the PEDOT-C 14 SC prevent the detachment of the ion-selective membrane (ISM) from its SC and the accumulation of an aqueous film between the ISM and the SC. The accumulation of an aqueous film between the ISM and its SC has a detrimental effect on the sensor performance. Although there is a test for the presence of an undesirable water layer, if the conditions for this test are not selected properly, it does not provide an unambiguous answer. On the other hand, recording the potential drifts of SC electrodes with pH-sensitive membranes in samples with different CO 2 levels can effectively prove the presence or absence of a water layer in a short time period.

Effect of egg washing and correlation between cuticle and egg penetration by various Salmonella strains.

PubMed

Gole, Vaibhav C; Roberts, Juliet R; Sexton, Margaret; May, Damian; Kiermeier, Andreas; Chousalkar, Kapil K

2014-07-16

In Australia, Europe and the United States, eggs and egg products are frequently associated with Salmonella food poisoning outbreaks. Many of the egg-associated Salmonella outbreaks have been due to the products such as mayonnaise, ice-cream and cold desserts which are eaten without cooking following the addition of raw egg. The ability of four Salmonella isolates (one each of S. Singapore, S. Adelaide, S. Worthington and S. Livingstone) to penetrate washed and unwashed eggs using whole egg and agar egg penetration methods was investigated in the current study. The results of the agar penetration experiment indicated that all the isolates used in the present study have the capacity to penetrate the eggshell. Eggshell penetration by the S. Worthington isolate was higher but not significant (p=0.06) in washed eggs compared to unwashed eggs. However, for all other isolates (S. Singapore, S. Adelaide and S. Livingstone), there was no significant difference in penetration of washed and unwashed eggs. Statistical analysis indicated that cuticle score was a significant linear predictor of Salmonella eggshell penetration. Whole egg penetration results showed that all of the Salmonella isolates used in the present study were capable of surviving on the eggshell surface after 21days of incubation (at 20°C) following a high dose of inoculation (10(5)CFU/mL). The combined data of all isolates demonstrated that, the survival rate of Salmonella on eggshells (inoculated with 10(5)CFU/mL) was significantly higher (p=0.002) at 20°C as compared to 37°C. S. Singapore, S. Worthington, and S. Livingstone were not detected in egg internal contents whereas S. Adelaide was detected in one egg's internal contents. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

Computational study of the heat transfer of an avian egg in a tray.

PubMed

Eren Ozcan, S; Andriessens, S; Berckmans, D

2010-04-01

The development of an embryo in an avian egg depends largely on its temperature. The embryo temperature is affected by its environment and the heat produced by the egg. In this paper, eggshell temperature and the heat transfer characteristics from one egg in a tray toward its environment are studied by means of computational fluid dynamics (CFD). Computational fluid dynamics simulations have the advantage of providing extensive 3-dimensional information on velocity and eggshell temperature distribution around an egg that otherwise is not possible to obtain by experiments. However, CFD results need to be validated against experimental data. The objectives were (1) to find out whether CFD can successfully simulate eggshell temperature from one egg in a tray by comparing to previously conducted experiments, (2) to visualize air flow and air temperature distribution around the egg in a detailed way, and (3) to perform sensitivity analysis on several variables affecting heat transfer. To this end, a CFD model was validated using 2 sets of temperature measurements yielding an effective model. From these simulations, it can be concluded that CFD can effectively be used to analyze heat transfer characteristics and eggshell temperature distribution around an egg. In addition, air flow and temperature distribution around the egg are visualized. It has been observed that temperature differences up to 2.6 degrees C are possible at high heat production (285 mW) and horizontal low flow rates (0.5 m/s). Sensitivity analysis indicates that average eggshell temperature is mainly affected by the inlet air velocity and temperature, flow direction, and the metabolic heat of the embryo and less by the thermal conductivity and emissivity of the egg and thermal emissivity of the tray.

Investigation of eggshell thickness and biochemical indicators of contaminant exposure in Great Blue Herons(Ardea herodias) from Mason Neck National Wildlife Refuge

USGS Publications Warehouse

Johnson, K.N.; Pinkney, A.E.; Melancon, M.J.; Hoffman, D.J.

2001-01-01

Mason Neck National Wildlife Refuge supports the largest great blue heron (Ardea herodias) rookery in the State of Virginia. The presence of bioaccumulative compounds such as polychlorinated biphenyls and DDT in fish collected from the Potomac River and tidal tributaries along the Refuge led to this study. The objective was to determine if there were any indications of pollutant-induced eggshell thinning or evidence of biochemical exposure to contaminants. We examined eggshell thickness and biomarkers of contaminant exposure in livers of embryos collected from the refuge and Coaches Island, a reference location in Chesapeake Bay. There was no evidence of eggshell thinning. Cytochrome P450 activity, measured as ethoxyresomfin-O-dealkylase (EROD) and benzyloxy-resorufin-O-dealkylase (BROD), was not significantly different in embryos from the two colonies. Biochemical indicators of oxidative stress can be reflected as changes in levels of reduced thiols, oxidized glutathione, and thiobarbituric reactive substances (TBARS). Although there were significant differences in the levels of reduced glutathione (GSH) and total thiol (TSH) activities in the embryo livers, there were no statistically significant differences in TBARS, protein-bound sulfhydryls (PBSH), oxidized glutathione (GSSG) and the ratio of GSSG to GSH. In fact, the concentrations of GSH and TSH were higher in the Mason Neck birds relative to Coaches Island. Under conditions of increased oxidative stress at least one or more of the following would be expected: decreased concentrations of reduced thiols (GSH and TSH), increased GSSG, and increased TBARS. In conclusion, we did not detect eggshell thinning or find evidence of a biochemical response to contaminant exposure in the Mason Neck great blue herons.

Determining the sources of calcium for migratory songbirds using stable strontium isotopes.

PubMed

Blum, Joel D; Taliaferro, E Hank; Holmes, Richard T

2001-02-01

We investigated natural variations in the stable isotopic composition of strontium (a surrogate for calcium) in the bones of a single species of breeding migratory songbird, as well as in their eggshells, egg contents, and food sources. We use this information to determine the sources of calcium to these migratory songbirds and their offspring. Samples were collected from two locations in the northeastern USA (Hubbard Brook, NH, and Downer Forest, VT.) that differed in soil geochemistry. The mean 87 Sr/ 86 Sr ratios of food items (caterpillars and snails), eggshells, and egg contents were indistinguishable within each site, but significantly different between the two sites. Mean 87 Sr/ 86 Sr ratios for the bones of adult females were significantly different between the two sites, but values were significantly lower than those of food items and eggshells at each site. Two of four adult individuals studied at each site had 87 Sr/ 86 Sr ratios lower than the entire range of values for local food sources. Mixing calculations indicate that up to 60% of skeletal strontium and calcium was derived from foods consumed in the winter grounds where lower 87 Sr/ 86 Sr ratios predominate. At each study site, the 87 Sr/ 86 Sr ratio of eggshells differed significantly between clutches, but the mean clutch 87 Sr/ 86 Sr ratios were unrelated to the skeletal 87 Sr/ 86 Sr ratio of the laying adult. These findings suggest that strontium (and hence calcium) for eggshell production in this species is derived predominantly from local food sources in breeding areas. Thus, reductions in available calcium in northern temperate ecosystems due to the influences of acid deposition could be potentially harmful to this and other species of migratory bird.

Clarification of effects of DDE on shell thickness, size, mass, and shape of avian eggs

USGS Publications Warehouse

Blus, Lawrence J.; Wiemeyer, Stanley N.; Bunck, Christine M.

1997-01-01

Moriarty et al. (1986) used field data to conclude that DDE decreased the size or altered the shape of avian eggs; therefore, they postulated that decreased eggshell thickness was a secondary effect because, as a general rule, thickness and egg size are positively correlated. To further test this relationship, the present authors analyzed data from eggs of captive American kestrels. Falco sparverius given DDT- or DDE-contaminated or clean diets and from wild brown pelicans Pelecanus occidentalis collected both before (pre-1946) and after (post-1945) DDT was introduced into the environment. Pertinent data from other field and laboratory studies were also summarized. DDE was not related to and did not affect size, mass, or shape of eggs of the brown pelican or American kestrel; but the relationship of DDE to eggshell thinning held true. Size and shape of eggs of brown pelicans from the post-1945 era and those of kestrels, on DDT-contaminated diets showed some significant, but inconsistent, changes compared to brown pelican data from the pre-1946 era or kestrels on clean diets. In contrast, nearly all samples of eggs of experimental kestrels given DDT-contaminated diets and those of wild brown pelicans from the post-1945 era exhibited significant eggshell thinning. Pertinent experimental studies with other sensitive avian species indicated no effects of DDE on the size or shape of eggs, even though the high dietary concentrations caused extreme eggshell thinning and mortality of some adult mallards (Anas platyrhynchos) in one study. These findings essentially controvert the argument that decreased eggshell thickness is a secondary effect resulting from the primary effect of DDE-induced changes in the size or shape of eggs.

Rapid determination of ions by combined solid-phase extraction--diffuse reflectance spectroscopy

NASA Technical Reports Server (NTRS)

Fritz, James S.; Arena, Matteo P.; Steiner, Steven A.; Porter, Marc D.

2003-01-01

We introduce colorimetric solid-phase extraction (C-SPE) for the rapid determination of selected ions. This new technique links the exhaustive concentration of an analyte by SPE onto a membrane disk surface for quantitative measurement with a hand-held diffuse reflectance spectrometer. The concentration/measurement procedure is complete in approximately 1 min and can be performed almost anywhere. This method has been used to monitor iodine and iodide in spacecraft water in the 0.1-5.0 ppm range and silver(I) in the range of 5.0-1000 microg/l. Applications to the trace analysis of copper(II), nickel(II), iron(III) and chromium(VI) are described. Studies on the mechanism of extraction showed that impregnation of the disk with a surfactant as well as a complexing reagent results in uptake of additional water, which markedly improves the extraction efficiency.

Effects of contaminants on Double-crested Cormorant reproduction in Green Bay, Wisconsin, USA

USGS Publications Warehouse

Custer, T.W.; Custer, Christine M.; Stromborg, K.L.; Melancon, M.J.; Adams, N.J.; Slotow, R.H.

1998-01-01

In 1994 and 1995, Double-crested Cormorants Phalacrocorax auritus were monitored from egg-laying through 12 days of age at Cat Island, Green Bay, Wisconsin, USA. Sample eggs at hatching were analysed for organochlorines (including total PCBs, PCB congeners, and DDE), hepatic microsomal ethoxyresorufin-O-dealkylase (EROD) activity in livers of embryos, and eggshell thickness. The number of eggs per nest that hatched and survived to i 2 days of age was estimated to be 2.2 in 1994 and 2.0 in 1995. Hatching success of eggs was not correlated with PCBs, the toxicity of PCBs based on congeners, or EROD activity. Hatching success was correlated with eggshell thickness and negatively correlated with DDE concentrations. Even though the insecticide DDT was banned in the early 1970s, we suggest that DDE concentrations in cormorant eggs in Green Bay are still having an affect on reproduction in this species.

Effects of contaminants on Double-crested Cormorant reproduction in Green Bay, Wisconsin, USA

USGS Publications Warehouse

Custer, T.W.; Custer, Christine M.; Stromborg, K.L.; Melancon, M.J.; Adams, N.J.; Slotow, R.H.

1999-01-01

In 1994 and 1995, Double-crested Cormorants Phalacrocorax auritus were monitored from egg-laying through 12 days of age at Cat Island, Green Bay, Wisconsin, USA. Sample eggs at hatching were analysed for organochlorines (including total PCBs, PCB congeners, and DDE), hepatic microsomal ethoxyresorufin-O-dealkylase (EROD) activity in livers of embryos, and eggshell thickness. The number of eggs per nest that hatched and survived to i 2 days of age was estimated to be 2.2 in 1994 and 2.0 in 1995. Hatching success of eggs was not correlated with PCBs, the toxicity of PCBs based on congeners, or EROD activity. Hatching success was correlated with eggshell thickness and negatively correlated with DDE concentrations. Even though the insecticide DDT was banned in the early 1970s, we suggest that DDE concentrations in cormorant eggs in Green Bay are still having an affect on reproduction in this species.

Numerical modeling of heat transfer and pasteurizing value during thermal processing of intact egg.

PubMed

Abbasnezhad, Behzad; Hamdami, Nasser; Monteau, Jean-Yves; Vatankhah, Hamed

2016-01-01

Thermal Pasteurization of Eggs, as a widely used nutritive food, has been simulated. A three-dimensional numerical model, computational fluid dynamics codes of heat transfer equations using heat natural convection, and conduction mechanisms, based on finite element method, was developed to study the effect of air cell size and eggshell thickness. The model, confirmed by comparing experimental and numerical results, was able to predict the temperature profiles, the slowest heating zone, and the required heating time during pasteurization of intact eggs. The results showed that the air cell acted as a heat insulator. Increasing the air cell volume resulted in decreasing of the heat transfer rate, and the increasing the required time of pasteurization (up to 14%). The findings show that the effect on thermal pasteurization of the eggshell thickness was not considerable in comparison to the air cell volume.

Chemically durable polymer electrolytes for solid-state alkaline water electrolysis

NASA Astrophysics Data System (ADS)

Park, Eun Joo; Capuano, Christopher B.; Ayers, Katherine E.; Bae, Chulsung

2018-01-01

Generation of high purity hydrogen using electrochemical splitting of water is one of the most promising methods for sustainable fuel production. The materials to be used as solid-state electrolytes for alkaline water electrolyzer require high thermochemical stability against hydroxide ion attack in alkaline environment during the operation of electrolysis. In this study, two quaternary ammonium-tethered aromatic polymers were synthesized and investigated for anion exchange membrane (AEM)-based alkaline water electrolyzer. The membranes properties including ion exchange capacity (IEC), water uptake, swelling degree, and anion conductivity were studied. The membranes composed of all C-C bond polymer backbones and flexible side chain terminated by cation head groups exhibited remarkably good chemical stability by maintaining structural integrity in 1 M NaOH solution at 95 °C for 60 days. Initial electrochemical performance and steady-state operation performance were evaluated, and both membranes showed a good stabilization of the cell voltage during the steady-state operation at the constant current density at 200 mA/cm2. Although both membranes in current form require improvement in mechanical stability to afford better durability in electrolysis operation, the next generation AEMs based on this report could lead to potentially viable AEM candidates which can provide high electrolysis performance under alkaline operating condition.

A highly reversible room-temperature lithium metal battery based on crosslinked hairy nanoparticles

NASA Astrophysics Data System (ADS)

Choudhury, Snehashis; Mangal, Rahul; Agrawal, Akanksha; Archer, Lynden A.

2015-12-01

Rough electrodeposition, uncontrolled parasitic side-reactions with electrolytes and dendrite-induced short-circuits have hindered development of advanced energy storage technologies based on metallic lithium, sodium and aluminium electrodes. Solid polymer electrolytes and nanoparticle-polymer composites have shown promise as candidates to suppress lithium dendrite growth, but the challenge of simultaneously maintaining high mechanical strength and high ionic conductivity at room temperature has so far been unmet in these materials. Here we report a facile and scalable method of fabricating tough, freestanding membranes that combine the best attributes of solid polymers, nanocomposites and gel-polymer electrolytes. Hairy nanoparticles are employed as multifunctional nodes for polymer crosslinking, which produces mechanically robust membranes that are exceptionally effective in inhibiting dendrite growth in a lithium metal battery. The membranes are also reported to enable stable cycling of lithium batteries paired with conventional intercalating cathodes. Our findings appear to provide an important step towards room-temperature dendrite-free batteries.

A highly reversible room-temperature lithium metal battery based on crosslinked hairy nanoparticles.

PubMed

Choudhury, Snehashis; Mangal, Rahul; Agrawal, Akanksha; Archer, Lynden A

2015-12-04

Rough electrodeposition, uncontrolled parasitic side-reactions with electrolytes and dendrite-induced short-circuits have hindered development of advanced energy storage technologies based on metallic lithium, sodium and aluminium electrodes. Solid polymer electrolytes and nanoparticle-polymer composites have shown promise as candidates to suppress lithium dendrite growth, but the challenge of simultaneously maintaining high mechanical strength and high ionic conductivity at room temperature has so far been unmet in these materials. Here we report a facile and scalable method of fabricating tough, freestanding membranes that combine the best attributes of solid polymers, nanocomposites and gel-polymer electrolytes. Hairy nanoparticles are employed as multifunctional nodes for polymer crosslinking, which produces mechanically robust membranes that are exceptionally effective in inhibiting dendrite growth in a lithium metal battery. The membranes are also reported to enable stable cycling of lithium batteries paired with conventional intercalating cathodes. Our findings appear to provide an important step towards room-temperature dendrite-free batteries.

A highly reversible room-temperature lithium metal battery based on crosslinked hairy nanoparticles

PubMed Central

Choudhury, Snehashis; Mangal, Rahul; Agrawal, Akanksha; Archer, Lynden A.

2015-01-01

Rough electrodeposition, uncontrolled parasitic side-reactions with electrolytes and dendrite-induced short-circuits have hindered development of advanced energy storage technologies based on metallic lithium, sodium and aluminium electrodes. Solid polymer electrolytes and nanoparticle-polymer composites have shown promise as candidates to suppress lithium dendrite growth, but the challenge of simultaneously maintaining high mechanical strength and high ionic conductivity at room temperature has so far been unmet in these materials. Here we report a facile and scalable method of fabricating tough, freestanding membranes that combine the best attributes of solid polymers, nanocomposites and gel-polymer electrolytes. Hairy nanoparticles are employed as multifunctional nodes for polymer crosslinking, which produces mechanically robust membranes that are exceptionally effective in inhibiting dendrite growth in a lithium metal battery. The membranes are also reported to enable stable cycling of lithium batteries paired with conventional intercalating cathodes. Our findings appear to provide an important step towards room-temperature dendrite-free batteries. PMID:26634644

Optimization of the β-Elimination/Michael Addition Chemistry on Reversed-Phase Supports for Mass Spectrometry Analysis of O-Linked Protein Modifications

PubMed Central

Nika, Heinz; Nieves, Edward; Hawke, David H.; Angeletti, Ruth Hogue

2013-01-01

We previously adapted the β-elimination/Michael addition chemistry to solid-phase derivatization on reversed-phase supports, and demonstrated the utility of this reaction format to prepare phosphoseryl peptides in unfractionated protein digests for mass spectrometric identification and facile phosphorylation-site determination. Here, we have expanded the use of this technique to β-N-acetylglucosamine peptides, modified at serine/threonine, phosphothreonyl peptides, and phosphoseryl/phosphothreonyl peptides, followed in sequence by proline. The consecutive β-elimination with Michael addition was adapted to optimize the solid-phase reaction conditions for throughput and completeness of derivatization. The analyte remained intact during derivatization and was recovered efficiently from the silica-based, reversed-phase support with minimal sample loss. The general use of the solid-phase approach for enzymatic dephosphorylation was demonstrated with phosphoseryl and phosphothreonyl peptides and was used as an orthogonal method to confirm the identity of phosphopeptides in proteolytic mixtures. The solid-phase approach proved highly suitable to prepare substrates from low-level amounts of protein digests for phosphorylation-site determination by chemical-targeted proteolysis. The solid-phase protocol provides for a simple, robust, and efficient tool to prepare samples for phosphopeptide identification in MALDI mass maps of unfractionated protein digests, using standard equipment available in most biological laboratories. The use of a solid-phase analytical platform is expected to be readily expanded to prepare digest from O-glycosylated- and O-sulfonated proteins for mass spectrometry-based structural characterization. PMID:23997661

A microstructure-based model for shape distortion during liquid phase sintering

NASA Astrophysics Data System (ADS)

Upadhyaya, Anish

Tight dimensional control is a major concern in consolidation of alloys via liquid phase sintering. This research demonstrates the role of microstructure in controlling the bulk dimensional changes that occur during liquid phase sintering. The dimensional changes were measured using a coordinate measuring machine and also on a real-time basis using in situ video imaging. To quantify compact distortion, a distortion parameter is formulated which takes into consideration the compact distortion in radial as well as axial directions. The microstructural attributes considered in this study are as follows: solid content, dihedral angle, grain size, grain contiguity and connectivity, and solid-solubility. Sintering experiments were conducted with the W-Ni-Cu, W-Ni-Fe, Mo-Ni-Cu, and Fe-Cu systems. The alloy systems and the compositions were selected to give a range of microstructures during liquid phase sintering. The results show that distortion correlates with the measured microstructural attributes. Systems containing a high solid content, high grain coordination number and contiguity, and large dihedral angle have more structural rigidity. The results show that a minimum two-dimensional grain coordination number of 3.0 is necessary for shape preservation. Based on the experimental observations, a model is derived that relates the critical solid content required for maintaining structural rigidity to the dihedral angle. The critical solid content decreases with an increasing dihedral angle. Consequently, W-Cu alloys, which have a dihedral angle of about 95sp°, can be consolidated without gross distortion with as little as 20 vol.% solid. To comprehensively understand the gravitational effects in the evolution of both the microstructure and the macrostructure during liquid phase sintering, W-Ni-Fe alloys with W content varying from 78 to 93 wt.% were sintered in microgravity. Compositions that slump during ground-based sintering also distort when sintered under microgravity. In ground-based sintering, low solid content alloys distort with a typical elephant-foot profile, while in microgravity, the compacts tend to spheroidize. This study shows that microstructural segregation occurs in both ground-based as well as microgravity sintering. In ground-based experiments, because of the density difference between the solid and the liquid phase, the solid content increases from top to the bottom of the sample. In microgravity, the solid content increases from periphery to the center of the samples. A model is derived to show that grain agglomeration and segregation are energetically favored events and will therefore be inherent to the system, even in the absence of gravity. Real time distortion measurement in alloys having appreciable solid-solubility in the liquid phase, such as W-Ni-Fe and Fe-Cu, show that the bulk of distortion occur within the first 5 min of melt formation. Distortion in such systems can be minimized by presaturating the matrix with the solid phase.

In situ synthesis of molecularly imprinted nanoparticles in porous support membranes using high-viscosity polymerization solvents.

PubMed

Renkecz, Tibor; László, Krisztina; Horváth, Viola

2012-06-01

There is a growing need in membrane separations for novel membrane materials providing selective retention. Molecularly imprinted polymers (MIPs) are promising candidates for membrane functionalization. In this work, a novel approach is described to prepare composite membrane adsorbers incorporating molecularly imprinted microparticles or nanoparticles into commercially available macroporous filtration membranes. The polymerization is carried out in highly viscous polymerization solvents, and the particles are formed in situ in the pores of the support membrane. MIP particle composite membranes selective for terbutylazine were prepared and characterized by scanning electron microscopy and N₂ porosimetry. By varying the polymerization solvent microparticles or nanoparticles with diameters ranging from several hundred nanometers to 1 µm could be embedded into the support. The permeability of the membranes was in the range of 1000 to 20,000 Lm⁻²  hr⁻¹  bar⁻¹. The imprinted composite membranes showed high MIP/NIP (nonimprinted polymer) selectivity for the template in organic media both in equilibrium-rebinding measurements and in filtration experiments. The solid phase extraction of a mixture of the template, its analogs, and a nonrelated compound demonstrated MIP/NIP selectivity and substance selectivity of the new molecularly imprinted membrane. The synthesis technique offers a potential for the cost-effective production of selective membrane adsorbers with high capacity and high throughput. Copyright © 2012 John Wiley & Sons, Ltd.

Structural and Electrochemical Consequences of Al and Ga Cosubstitution in Li7La3Zr2O12 Solid Electrolytes

PubMed Central

2016-01-01

Several “Beyond Li-Ion Battery” concepts such as all solid-state batteries and hybrid liquid/solid systems envision the use of a solid electrolyte to protect Li-metal anodes. These configurations are very attractive due to the possibility of exceptionally high energy densities and high (dis)charge rates, but they are far from being realized practically due to a number of issues including high interfacial resistance and difficulties associated with fabrication. One of the most promising solid electrolyte systems for these applications is Al or Ga stabilized Li7La3Zr2O12 (LLZO) based on high ionic conductivities and apparent stability against reduction by Li metal. Nevertheless, the fabrication of dense LLZO membranes with high ionic conductivity and low interfacial resistances remains challenging; it definitely requires a better understanding of the structural and electrochemical properties. In this study, the phase transition from garnet (Ia3̅d, No. 230) to “non-garnet” (I4̅3d, No. 220) space group as a function of composition and the different sintering behavior of Ga and Al stabilized LLZO are identified as important factors in determining the electrochemical properties. The phase transition was located at an Al:Ga substitution ratio of 0.05:0.15 and is accompanied by a significant lowering of the activation energy for Li-ion transport to 0.26 eV. The phase transition combined with microstructural changes concomitant with an increase of the Ga/Al ratio continuously improves the Li-ion conductivity from 2.6 × 10–4 S cm–1 to 1.2 × 10–3 S cm–1, which is close to the calculated maximum for garnet-type materials. The increase in Ga content is also associated with better densification and smaller grains and is accompanied by a change in the area specific resistance (ASR) from 78 to 24 Ω cm2, the lowest reported value for LLZO so far. These results illustrate that understanding the structure–properties relationships in this class of materials allows practical obstacles to its utilization to be readily overcome. PMID:27110064

Structural and Electrochemical Consequences of Al and Ga Cosubstitution in Li7La3Zr2O12 Solid Electrolytes.

PubMed

Rettenwander, Daniel; Redhammer, Günther; Preishuber-Pflügl, Florian; Cheng, Lei; Miara, Lincoln; Wagner, Reinhard; Welzl, Andreas; Suard, Emmanuelle; Doeff, Marca M; Wilkening, Martin; Fleig, Jürgen; Amthauer, Georg

2016-04-12

Several "Beyond Li-Ion Battery" concepts such as all solid-state batteries and hybrid liquid/solid systems envision the use of a solid electrolyte to protect Li-metal anodes. These configurations are very attractive due to the possibility of exceptionally high energy densities and high (dis)charge rates, but they are far from being realized practically due to a number of issues including high interfacial resistance and difficulties associated with fabrication. One of the most promising solid electrolyte systems for these applications is Al or Ga stabilized Li 7 La 3 Zr 2 O 12 (LLZO) based on high ionic conductivities and apparent stability against reduction by Li metal. Nevertheless, the fabrication of dense LLZO membranes with high ionic conductivity and low interfacial resistances remains challenging; it definitely requires a better understanding of the structural and electrochemical properties. In this study, the phase transition from garnet ( Ia 3̅ d , No. 230) to "non-garnet" ( I 4̅3 d , No. 220) space group as a function of composition and the different sintering behavior of Ga and Al stabilized LLZO are identified as important factors in determining the electrochemical properties. The phase transition was located at an Al:Ga substitution ratio of 0.05:0.15 and is accompanied by a significant lowering of the activation energy for Li-ion transport to 0.26 eV. The phase transition combined with microstructural changes concomitant with an increase of the Ga/Al ratio continuously improves the Li-ion conductivity from 2.6 × 10 -4 S cm -1 to 1.2 × 10 -3 S cm -1 , which is close to the calculated maximum for garnet-type materials. The increase in Ga content is also associated with better densification and smaller grains and is accompanied by a change in the area specific resistance (ASR) from 78 to 24 Ω cm 2 , the lowest reported value for LLZO so far. These results illustrate that understanding the structure-properties relationships in this class of materials allows practical obstacles to its utilization to be readily overcome.

High Temperature Protonic Conductors

NASA Technical Reports Server (NTRS)

Dynys, Fred; Berger, Marie-Helen; Sayir, Ali

2007-01-01

High Temperature Protonic Conductors (HTPC) with the perovskite structure are envisioned for electrochemical membrane applications such as H2 separation, H2 sensors and fuel cells. Successive membrane commercialization is dependent upon addressing issues with H2 permeation rate and environmental stability with CO2 and H2O. HTPC membranes are conventionally fabricated by solid-state sintering. Grain boundaries and the presence of intergranular second phases reduce the proton mobility by orders of magnitude than the bulk crystalline grain. To enhanced protonic mobility, alternative processing routes were evaluated. A laser melt modulation (LMM) process was utilized to fabricate bulk samples, while pulsed laser deposition (PLD) was utilized to fabricate thin film membranes . Sr3Ca(1+x)Nb(2-x)O9 and SrCe(1-x)Y(x)O3 bulk samples were fabricated by LMM. Thin film BaCe(0.85)Y(0.15)O3 membranes were fabricated by PLD on porous substrates. Electron microscopy with chemical mapping was done to characterize the resultant microstructures. High temperature protonic conduction was measured by impedance spectroscopy in wet air or H2 environments. The results demonstrate the advantage of thin film membranes to thick membranes but also reveal the negative impact of defects or nanoscale domains on protonic conductivity.

Membrane-Protein Binding Measured with Solution-Phase Plasmonic Nanocube Sensors

PubMed Central

Wu, Hung-Jen; Henzie, Joel; Lin, Wan-Chen; Rhodes, Christopher; Li, Zhu; Sartorel, Elodie; Thorner, Jeremy; Yang, Peidong; Groves, Jay. T.

2013-01-01

We describe a solution-phase sensor of lipid-protein binding based on localized surface plasmon resonance (LSPR) of silver nanocubes. When silica-coated nanocubes are mixed into a suspension of lipid vesicles, supported membranes spontaneously assemble on their surfaces. Using a standard laboratory spectrophotometer, we calibrate the LSPR peak shift due to protein binding to the membrane surface and then characterize the lipid-binding specificity of a pleckstrin-homology domain protein. PMID:23085614

Cooling induces phase separation in membranes derived from isolated CNS myelin

PubMed Central

Pusterla, Julio M.; Schneck, Emanuel; Funari, Sérgio S.; Démé, Bruno; Tanaka, Motomu

2017-01-01

Purified myelin membranes (PMMs) are the starting material for biochemical analyses such as the isolation of detergent-insoluble glycosphingolipid-rich domains (DIGs), which are believed to be representatives of functional lipid rafts. The normal DIGs isolation protocol involves the extraction of lipids under moderate cooling. Here, we thus address the influence of cooling on the structure of PMMs and its sub-fractions. Thermodynamic and structural aspects of periodic, multilamellar PMMs are examined between 4°C and 45°C and in various biologically relevant aqueous solutions. The phase behavior is investigated by small-angle X-ray scattering (SAXS) and differential scanning calorimetry (DSC). Complementary neutron diffraction (ND) experiments with solid-supported myelin multilayers confirm that the phase behavior is unaffected by planar confinement. SAXS and ND consistently show that multilamellar PMMs in pure water become heterogeneous when cooled by more than 10–15°C below physiological temperature, as during the DIGs isolation procedure. The heterogeneous state of PMMs is stabilized in physiological solution, where phase coexistence persists up to near the physiological temperature. This result supports the general view that membranes under physiological conditions are close to critical points for phase separation. In presence of elevated Ca2+ concentrations (> 10 mM), phase coexistence is found even far above physiological temperatures. The relative fractions of the two phases, and thus presumably also their compositions, are found to vary with temperature. Depending on the conditions, an “expanded” phase with larger lamellar period or a “compacted” phase with smaller lamellar period coexists with the native phase. Both expanded and compacted periods are also observed in DIGs under the respective conditions. The observed subtle temperature-dependence of the phase behavior of PMMs suggests that the composition of DIGs is sensitive to the details of the isolation protocol. PMID:28915267

360-degrees profilometry using strip-light projection coupled to Fourier phase-demodulation.

PubMed

Servin, Manuel; Padilla, Moises; Garnica, Guillermo

2016-01-11

360 degrees (360°) digitalization of three dimensional (3D) solids using a projected light-strip is a well-established technique in academic and commercial profilometers. These profilometers project a light-strip over the digitizing solid while the solid is rotated a full revolution or 360-degrees. Then, a computer program typically extracts the centroid of this light-strip, and by triangulation one obtains the shape of the solid. Here instead of using intensity-based light-strip centroid estimation, we propose to use Fourier phase-demodulation for 360° solid digitalization. The advantage of Fourier demodulation over strip-centroid estimation is that the accuracy of phase-demodulation linearly-increases with the fringe density, while in strip-light the centroid-estimation errors are independent. Here we proposed first to construct a carrier-frequency fringe-pattern by closely adding the individual light-strip images recorded while the solid is being rotated. Next, this high-density fringe-pattern is phase-demodulated using the standard Fourier technique. To test the feasibility of this Fourier demodulation approach, we have digitized two solids with increasing topographic complexity: a Rubik's cube and a plastic model of a human-skull. According to our results, phase demodulation based on the Fourier technique is less noisy than triangulation based on centroid light-strip estimation. Moreover, Fourier demodulation also provides the amplitude of the analytic signal which is a valuable information for the visualization of surface details.

The eggshell: strength, structure and function.

PubMed

Solomon, S E

2010-08-01

In making a journey through the literature of the last 50 years one can easily highlight a sequence of seminal works-but the route has not been direct and to avoid the many profitable diversions and detours that have enriched and deepened our collective understanding of the subject of eggshell structure and function is to do the subject a serious disservice. This is a route march of science enabled by advances in technology.

Preparation and properties of calcium oxide from eggshells via calcination

NASA Astrophysics Data System (ADS)

Tangboriboon, N.; Kunanuruksapong, R.; Sirivat, A.

2012-12-01

Duck eggs are one of the most versatile cooking ingredients in which residue eggshells are discarded. Raw duck eggshells were calcined at temperatures between 300 to 900 °C, for 1, 3, and 5 h. Both the raw and calcined duck eggshells were characterized by FTIR, STA, XRD, XRF, TEM, BET, a particle size analyzer, and an impedance analyzer. The proper calcination conditions are: 900 °C and 1 h, yielding calcium oxide with a purity of 99.06 % w/w. The calcium carbonate of the rhombohedral form (CaCO3) transforms completely into the calcium oxide or lime of the face centered cubic form (CaO) at 900 °C, as shown by XRD diffraction patterns. The transmission electron microscopy (TEM) images of the calcium oxide reveal a moderately good dispersion of nearly uniform particles. The calcium oxide has a white color, a spherical shape, high porosity, and narrow particles size distribution. The percentage of ceramic yield of the calcium oxide is 53.53, as measured by STA (TG-DTA-DTG). The calcium oxide has a N2 adsorption-desorption isotherm indicating the meso-porosity range. The dielectric constant and the electrical conductivity of the calcined calcium oxide are 35 and 1:0×10-6(Ω·m)-1, respectively, at the frequency of 500 Hz.

Valorization of crude glycerol and eggshell biowaste as media components for hydrogen production: A scale-up study using co-culture system.

PubMed

Pachapur, Vinayak Laxman; Das, Ratul Kumar; Brar, Satinder Kaur; Le Bihan, Yann; Buelna, Gerardo

2017-02-01

The properties of eggshells (EGS) as neutralizing and immobilizing agent were investigated for hydrogen (H 2 ) production using crude glycerol (CG) by co-culture system. Eggshells of different sizes and concentrations were used during batch and repeated-batch fermentation. For batch and repeated-batch fermentation, the maximum H 2 production (36.53±0.53 and 41.16±0.95mmol/L, respectively) was obtained with the EGS size of 33μm

Effects of Dietary Cadmium and Boron Supplementation on Performance, Eggshell Quality and Mineral Concentrations of Bone in Laying Hens.

PubMed

Olgun, Osman; Bahtiyarca, Yilmaz

2015-09-01

This study was conducted to determine the effects of supplementation of different levels of cadmium and boron on performance, eggshell quality, and mineral concentrations of bone in layer diets. In this trial, a total of 144 layer chickens, 21 weeks old, were randomly divided into 12 experimental groups. In each experimental group, there were four replicates, and in each of the replicates, there were three hens. Experimental diets consisted of all possible combinations of four levels of added cadmium (0, 5, 15, and 45 mg/kg) and three levels of added boron (0, 60, and 120 mg/kg) to the basal diet. Added cadmium (15 or 45 mg/kg) had a significant adverse effect on performance parameters (P < 0.01). Eggshell thickness increased with the addition of 5 mg/kg level of cadmium to the diet (P < 0.01). Tibia cadmium content increased with the addition of cadmium and boron in the diet (P < 0.01). However, tibia boron content decreased with the supplementation of cadmium (P < 0.01). These results indicate that the addition of boron to the diet did not prevent adverse effect of cadmium on performance and eggshell quality, or accumulation of cadmium in bone.

Effect of Egg Washing and Correlation between Eggshell Characteristics and Egg Penetration by Various Salmonella Typhimurium Strains

PubMed Central

Gole, Vaibhav C.; Chousalkar, Kapil K.; Roberts, Juliet R.; Sexton, Margaret; May, Damian; Tan, Jessica; Kiermeier, Andreas

2014-01-01

Salmonella is an important foodborne pathogen, causing an estimated 11,992 cases of infection in Australia per year. Egg or egg product related salmonellosis is a major concern for the egg industry. Worldwide, S. Typhimurium is one of the most common serovars identified in Salmonella food poisoning cases. The current study investigated the ability of five S. Typhimurium strains to penetrate washed and unwashed eggs using whole egg and agar egg penetration methods. All S. Typhimurium strains were able to penetrate eggshells and survive in egg albumen (at 20°C) according to whole egg penetration results. Polymerase Chain Reaction results demonstrated that S. Typhimurium strain 2 (103 and 105 CFU/mL), and strain 5 (103 and 105 CFU/mL) egg penetration was significantly higher (p<0.05) in washed eggs when compared to unwashed eggs. Statistical analysis of the agar penetration experiment indicated that S. Typhimurium was able to penetrate washed eggs at a significantly higher rate when compared to unwashed eggs (p<0.05). When compared to unwashed eggs, washed eggs also had significantly damaged cuticles. Statistical analysis also indicated that eggshell penetration by S. Typhimurium was related to various eggshell ultrastructural features such as cap quality, alignment, erosion, confluence, Type B bodies and cuticle cover. PMID:24621821

Abrupt recent shift in δ13C and δ15N values in Adélie penguin eggshell in Antarctica

PubMed Central

Emslie, Steven D.; Patterson, William P.

2007-01-01

Stable isotope values of carbon (δ13C) and nitrogen (δ15N) in blood, feathers, eggshell, and bone have been used in seabird studies since the 1980s, providing a valuable source of information on diet, foraging patterns, and migratory behavior in these birds. These techniques can also be applied to fossil material when preservation of bone and other tissues is sufficient. Excavations of abandoned Adélie penguin (Pygoscelis adeliae) colonies in Antarctica often provide well preserved remains of bone, feathers, and eggshell dating from hundreds to thousands of years B.P. Herein we present an ≈38,000-year time series of δ13C and δ15N values of Adélie penguin eggshell from abandoned colonies located in three major regions of Antarctica. Results indicate an abrupt shift to lower-trophic prey in penguin diets within the past ≈200 years. We posit that penguins only recently began to rely on krill as a major portion of their diet, in conjunction with the removal of baleen whales and krill-eating seals during the historic whaling era. Our results support the “krill surplus” hypothesis that predicts excess krill availability in the Southern Ocean after this period of exploitation. PMID:17620620

Determination of 15 N-nitrosodimethylamine precursors in different water matrices by automated on-line solid-phase extraction ultra-high-performance-liquid chromatography tandem mass spectrometry.

PubMed

Farré, Maria José; Insa, Sara; Mamo, Julian; Barceló, Damià

2016-08-05

A new methodology based on on-line solid-phase extraction (SPE) ultra-high-performance-liquid chromatography coupled to a triple quadrupole mass spectrometer (UHPLC-MS-MS) for the determination of 15 individual anthropogenic N-nitrosodimethylamine (NDMA) precursors was developed. On-line SPE was performed by passing 2mL of the water sample through a Hypersil GOLD aQ column and chromatographic separation was done using a Kinetex Biphenyl column using methanol and 0.1% formic acid aqueous solution as a mobile phase. For unequivocal identification and confirmation, two selected reaction monitoring (SRM) transitions were monitored per compound. Quantification was performed by internal standard approach and matrix match calibration. The main advantages of the developed method are high sensitivity (limits of detection in the sub ng/L range), selectivity due to the use of tandem mass spectrometry, precision and minimum sample manipulation as well as fast analytical response. Process efficiency and recovery were also evaluated for all the target compounds. As part of the validation procedure, the method was applied in a sampling campaign for the analysis of influent and secondary effluent of a wastewater treatment plant (WWTP) in Girona, Spain. Additionally, the effluent from a nanofiltration (NF) membrane system used for water recycling was monitored. The percentage of NDMA formation explained by the measured precursors was also quantified. Copyright © 2016 Elsevier B.V. All rights reserved.

A two-photon view of an enzyme at work: Crotalus atrox venom PLA2 interaction with single-lipid and mixed-lipid giant unilamellar vesicles.

PubMed Central

Sanchez, Susana A; Bagatolli, Luis A; Gratton, Enrico; Hazlett, Theodore L

2002-01-01

We describe the interaction of Crotalus atrox-secreted phospholipase A2 (sPLA2) with giant unilamellar vesicles (GUVs) composed of single and binary phospholipid mixtures visualized through two-photon excitation fluorescent microscopy. The GUV lipid compositions that we examined included 1-palmitoyl-2-oleoyl-phosphatidylcholine, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) (above their gel-liquid crystal transition temperatures) and two well characterized lipid mixtures, 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine (DMPE):DMPC (7:3) and 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC)/1,2-diarachidoyl-sn-glycero-3-phosphocholine (DAPC) (1:1) equilibrated at their phase-coexistence temperature regime. The membrane fluorescence probes, 6-lauroyl-2-(dimethylamino) napthalene, 6-propionyl-2-(dimethylamino) naphthalene, and rhodamine-phosphatidylethanolamine, were used to assess the state of the membrane and specifically mark the phospholipid domains. Independent of their lipid composition, all GUVs were reduced in size as sPLA2-dependent lipid hydrolysis proceeded. The binding of sPLA2 was monitored using a fluorescein-sPLA2 conjugate. The sPLA2 was observed to associate with the entire surface of the liquid phase in the single phospholipid GUVs. In the mixed-lipid GUV's, at temperatures promoting domain coexistence, a preferential binding of the enzyme to the liquid regions was also found. The lipid phase of the GUV protein binding region was verified by the introduction of 6-propionyl-2-(dimethylamino) naphthalene, which partitions quickly into the lipid fluid phase. Preferential hydrolysis of the liquid domains supported the conclusions based on the binding studies. sPLA2 hydrolyzes the liquid domains in the binary lipid mixtures DLPC:DAPC and DMPC:DMPE, indicating that the solid-phase packing of DAPC and DMPE interferes with sPLA2 binding, irrespective of the phospholipid headgroup. These studies emphasize the importance of lateral packing of the lipids in C. atrox sPLA2 enzymatic hydrolysis of a membrane surface. PMID:11916878

Interactions of Aqueous Imidazolium-Based Ionic Liquid Mixtures with Solid-Supported Phospholipid Vesicles

PubMed Central

Losada-Pérez, Patricia; Khorshid, Mehran; Renner, Frank Uwe

2016-01-01

Despite the environmentally friendly reputation of ionic liquids (ILs), their safety has been recently questioned given their potential as cytotoxic agents. The fundamental mechanisms underlying the interactions between ILs and cells are less studied and by far not completely understood. Biomimetic films are here important biophysical model systems to elucidate fundamental aspects and mechanisms relevant for a large range of biological interaction ranging from signaling to drug reception or toxicity. Here we use dissipative quartz crystal microbalance QCM-D to examine the effect of aqueous imidazolium-based ionic liquid mixtures on solid-supported biomimetic membranes. Specifically, we assess in real time the effect of the cation chain length and the anion nature on a supported vesicle layer of the model phospholipid DMPC. Results indicate that interactions are mainly driven by the hydrophobic components of the IL, which significantly distort the layer and promote vesicle rupture. Our analyses evidence the gradual decrease of the main phase transition temperature upon increasing IL concentration, reflecting increased disorder by weakening of lipid chain interactions. The degree of rupture is significant for ILs with long hydrophobic cation chains and large hydrophobic anions whose behavior is reminiscent of that of antimicrobial peptides. PMID:27684947

Water Transport in Bicontinuous, Phase-Separated Membranes Made from Reactive Block Copolymers

DTIC Science & Technology

2014-12-01

polyurethane foam impregnated with activated carbon, a design that allows perspiration to evaporate while chemical agents are adsorbed onto the activated... dispersed into a minimal volume (4–5 drops) of ethanol. The catalyst solution was then added to the polymer solution while stirring rapidly. The solution...substituted styrene monomer; one interior block with units of other styrene monomers which have been sulfonated; non- dispersible and solid in water

Melting along the Hugoniot and solid phase transition for Sn via sound velocity measurements

NASA Astrophysics Data System (ADS)

Song, Ping; Cai, Ling-cang; Tao, Tian-jiong; Yuan, Shuai; Chen, Hong; Huang, Jin; Zhao, Xin-wen; Wang, Xue-jun

2016-11-01

It is very important to determine the phase boundaries for materials with complex crystalline phase structures to construct their corresponding multi-phase equation of state. By measuring the sound velocity of Sn with different porosities, different shock-induced melting pressures along the solid-liquid phase boundary could be obtained. The incipient shock-induced melting of porous Sn samples with two different porosities occurred at a pressure of about 49.1 GPa for a porosity of 1.01 and 45.6 GPa for a porosity of 1.02, based on measurements of the sound velocity. The incipient shock-induced melting pressure of solid Sn was revised to 58.1 GPa using supplemental measurements of the sound velocity. Trivially, pores in Sn decreased the shock-induced melting pressure. Based on the measured longitudinal sound velocity data, a refined solid phase transition and the Hugoniot temperature-pressure curve's trend are discussed. No bcc phase transition occurs along the Hugoniot for porous Sn; further investigation is required to understand the implications of this finding.

Structural study of the membrane protein MscL using cell-free expression and solid-state NMR

NASA Astrophysics Data System (ADS)

Abdine, Alaa; Verhoeven, Michiel A.; Park, Kyu-Ho; Ghazi, Alexandre; Guittet, Eric; Berrier, Catherine; Van Heijenoort, Carine; Warschawski, Dror E.

2010-05-01

High-resolution structures of membrane proteins have so far been obtained mostly by X-ray crystallography, on samples where the protein is surrounded by detergent. Recent developments of solid-state NMR have opened the way to a new approach for the study of integral membrane proteins inside a membrane. At the same time, the extension of cell-free expression to the production of membrane proteins allows for the production of proteins tailor made for NMR. We present here an in situ solid-state NMR study of a membrane protein selectively labeled through the use of cell-free expression. The sample consists of MscL (mechano-sensitive channel of large conductance), a 75 kDa pentameric α-helical ion channel from Escherichia coli, reconstituted in a hydrated lipid bilayer. Compared to a uniformly labeled protein sample, the spectral crowding is greatly reduced in the cell-free expressed protein sample. This approach may be a decisive step required for spectral assignment and structure determination of membrane proteins by solid-state NMR.