The 3rd CARISMA international conference on medium and high temperature proton exchange membrane fuel cells: Three approaches to better platinum catalysts at biannual conference

DEFF Research Database (Denmark)

Jensen, Jens Oluf; Cleemann, Lars Nilausen; Li, Qingfeng

2013-01-01

exchange membrane fuel cells (PEMFCs) to be operated at intermediate and high temperatures. The conference series was initiated by the European CARISMA Coordination Action for Research on Intermediate and High Temperature Specialized Membrane Electrode Assemblies. The 2012 event in Copenhagen had around...

Predictors of Coordinated and Comprehensive Care Within a Medical Home for Children With Special Healthcare (CHSCN Needs

Directory of Open Access Journals (Sweden)

Ashley Walker

2018-06-01

Full Text Available The purpose of this study was to examine predictors of coordinated and comprehensive care within a medical home among children with special health care needs (CSHCN. The latest version of the National Survey of Children with Special Health Care Needs (NS-CSHCN employed a national random-digit-dial sample whereby US households were screened, resulting in 40,242 eligible respondents. Logistic regression analyses were performed modeling the probability of coordinated, comprehensive care in a medical home based on shared decision-making and other factors. A total of 29,845 cases were selected for inclusion in the model. Of these, 17,390 cases (58.3% met the criteria for coordinated, comprehensive care in a medical home. Access to a community-based service systems had the greatest positive impact on coordinated, comprehensive care in a medical home. Adequate insurance coverage and being White/Caucasian were also positively associated with the dependent variable. Shared decision-making was reported by 72% of respondents and had a negative, but relatively negligible impact on coordinated, comprehensive care in a medical home. Increasing age, non-traditional family structures, urban residence, and public insurance were more influential, and negatively impacted the dependent variable. Providers and their respective organizations should seek to expand and improve health and support services at the community level.

Care Coordination with Schools: The Role of Family-Centered Care for Children with Special Health Care Needs.

Science.gov (United States)

Barnard-Brak, Lucy; Stevens, Tara; Carpenter, Julianna

2017-05-01

Objectives Family-centered care has been associated with positive outcomes for children with special health care needs. The purpose of the current study was to examine the relationship of family-centered care as associated with care coordination with schools and school absences (e.g., missed days) as reported by parents of children with special health care needs. Methods The current study utilized data from the National Survey of Children with Special Health Care Needs 2009-201 (N = 40,242) to achieve this purpose. The National Survey of Children with Special Health Care Needs may be considered a nationally-representative and community-based sample of parent responses for children with special health care needs across the United States. Results Results from the current study indicate that family-centered care is associated with fewer absences and improved care coordination with schools when applicable. The variables of functional difficulties, poverty level, and the number of conditions were statistically controlled. Conclusions We suggest that the positive influence of family-centered care when practiced extends beyond the family and interacts with educational outcomes. We also suggest that the role of schools appears to be under-studied given the role that schools can play in family-centered care.

Ideology Influencing Action: Special Educational Needs Co-Ordinator and Learning Support Assistant Role Conceptualisations and Experiences of Special Needs Education in England

Science.gov (United States)

Maher, Anthony John; Vickerman, Philip

2018-01-01

One outcome of England's Code of Practice' (DfE, 1994) was an increase, first, in the number of learning support assistants (LSAs) working in mainstream schools and, second, the establishment of the role of special educational needs co-ordinator (SENCO). Semi-structured interviews were conducted with SENCOs and LSAs to explore: (i) why they chose…

Towards Acid-Tolerated Ethanol Dehydration: Chitosan-Based Mixed Matrix Membranes Containing Cyano-Bridged Coordination Polymer Nanoparticles.

Science.gov (United States)

Wu, C-W; Kang, Chao-Hsiang; Lin, Yi-Feng; Tung, Kuo-Lun; Deng, Yu-Heng; Ahamad, Tansir; Alshehri, Saad M; Suzuki, Norihiro; Yamauchi, Yusuke

2016-04-01

Prussian blue (PB) nanoparticles, one of many cyano-bridged coordination polymers, are successfully incorporated into chitosan (CS) polymer to prepare PB/CS mixed matrix membranes (MMMs). The PB nanoparticles are uniformly distributed in the MMMs without the collapse of the original PB structure. As-prepared PB/CS MMMs are used for ethanol dehydration at 25 °C in the pervaporation process. The effect of loading PB in CS matrix on pervaporation performance is carefully investigated. The PB/CS membrane with 30 wt% PB loading shows the best performance with a permeate flux of 614 g. m-2 . h-1 and a separation factor of 1472. The pervaporation using our PB/CS membranes exhibits outstanding performance in comparison with the previously reported CS-based membranes and MMMs. Furthermore, the addition of PB allows PB/CS MMMs to be tolerant of acidic environment. The present work demonstrates good pervaporation performance of PB/CS MMMs for the separation of an ethanol/water (90:10 in wt%) solution. Our new system provides an opportunity for dehydration of bioethanol in the future.

[Coupling coordination evaluation method between eco-environment quality and economic development level in contiguous special poverty-stricken areas of China].

Science.gov (United States)

Wang, Yan-hui; Li, Jing-yi

2015-05-01

It is one of the important strategies in the new period of national poverty alleviation and development to maintain the basic balance between the ecological environment and economic development, and to promote the coordinated sustainable development of economy and ecological environment. Taking six contiguous special poverty-stricken areas as the study areas, a coupling coordination evaluation method between eco-environment quality and economic development level in contiguous special poverty-stricken areas was explored in this paper. The region' s ecological poverty index system was proposed based on the natural attribute of ecological environment, and the ecological environment quality evaluation method was built up by using AHP weighting method, followed by the design of the coupling coordination evaluation method between the ecological environment indices and the county economic poverty comprehensive indices. The coupling coordination degrees were calculated and their spatial representation differentiations were analyzed respectively at district, province, city, and county scales. Results showed that approximately half of the counties in the study areas achieved the harmoniously coordinated development. However, the ecological environmental quality and the economic development in most counties could not be synchronized, where mountains, rivers and other geographic features existed roughly as a dividing line of the coordinated development types. The phenomena of dislocation between the ecological environment and economic development in state-level poor counties were more serious than those of local poor counties.

Development of a hospital-based care coordination program for children with special health care needs.

Science.gov (United States)

Petitgout, Janine M; Pelzer, Daniel E; McConkey, Stacy A; Hanrahan, Kirsten

2013-01-01

A hospital-based Continuity of Care program for children with special health care needs is described. A family-centered team approach provides care coordination and a medical home. The program has grown during the past 10 years to include inpatients and outpatients from multiple services and outreach clinics. Improved outcomes, including decreased length of stay, decreased cost, and high family satisfaction, are demonstrated by participants in the program. Pediatric nurse practitioners play an important role in the medical home, collaborating with primary care providers, hospital-based specialists, community services, and social workers to provide services to children with special health care needs. Copyright © 2013 National Association of Pediatric Nurse Practitioners. Published by Mosby, Inc. All rights reserved.

The impact of development o f the special coordination abilities on the general skill ability for table tennis juniors under 12 years old

Directory of Open Access Journals (Sweden)

Shawkat Gaber Radwan

2014-06-01

Full Text Available Indicates each of Muhama d Allawi (2002, Essam Abdul Khaliq (2003, and Walf Droge (2002 that the coordination abilities are closely related to the development of technical motor skills, and that pra ctitioner athletic activity which determines the quality of this abilities should be developed, where the player can not master the technical skills in the special activity in case lack of special coordination abilities for this activity. Both Manf red Must er (1986, Jürgen Schmicker (2000, Wolfgang and others (2000 and Wohlgefahrt, Karlheinz (2004 refers that the special coordination abilities for table tennis include each of: 1 - The motor adaptation and adjustment ability, 2 - The ability to differentiat e , 3 - reaction speed ability, 4 - orientation ability, 5 - balance ability, 6 - coupling ability, 7 - The ability to sense the rhythm. The aim of this study is design training program to development the special coordination abilities of table tennis and identi fies the impact of this program on the general skill ability for table tennis juniors under 12 years old. The researcher used the experimental method into two groups one experimental and the other control group the strength of each of them is 8 of table te nnis juniors in Ismailia city in Egypt. The duration of the program is three months, three training units a week the duration of each training unit is 90 minutes. The most important results of this study was the training program led to improvement the spec ial coordination abilities of table tennis for the experimental group, which led to high level of the general skill ability in table tennis for the experimental group more than the control group .

Coordinating structural and functional synapse development: postsynaptic p21-activated kinase independently specifies glutamate receptor abundance and postsynaptic morphology.

Science.gov (United States)

Albin, Stephanie D; Davis, Graeme W

2004-08-04

Here, we show that postsynaptic p21-activated kinase (Pak) signaling diverges into two genetically separable pathways at the Drosophila neuromuscular junction. One pathway controls glutamate receptor abundance. Pak signaling within this pathway is specified by a required interaction with the adaptor protein Dreadlocks (Dock). We demonstrate that Dock is localized to the synapse via an Src homology 2-mediated protein interaction. Dock is not necessary for Pak localization but is necessary to restrict Pak signaling to control glutamate receptor abundance. A second genetically separable function of Pak kinase signaling controls muscle membrane specialization through the regulation of synaptic Discs-large. In this pathway, Dock is dispensable. We present a model in which divergent Pak signaling is able to coordinate two different features of postsynaptic maturation, receptor abundance, and muscle membrane specialization.

Metamaterial membranes

International Nuclear Information System (INIS)

Restrepo-Flórez, Juan Manuel; Maldovan, Martin

2017-01-01

We introduce a new class of metamaterial device to achieve separation of compounds by using coordinate transformations and metamaterial theory. By rationally designing the spatial anisotropy for mass diffusion, we simultaneously concentrate different compounds in different spatial locations, leading to separation of mixtures across a metamaterial membrane. The separation of mixtures into their constituent compounds is critically important in biophysics, biomedical, and chemical applications. We present a practical case where a mixture of oxygen and nitrogen diffusing through a polymeric planar matrix is separated. This work opens doors to new paradigms in membrane separations via coordinate transformations and metamaterials by introducing novel properties and unconventional mass diffusion phenomena. (paper)

Focus on Membrane Differentiation and Membrane Domains in the Prokaryotic Cell

NARCIS (Netherlands)

Boekema, Egbert J.; Scheffers, Dirk-Jan; van Bezouwen, Laura S.; Bolhuis, Henk; Folea, I. Mihaela

2013-01-01

A summary is presented of membrane differentiation in the prokaryotic cell, with an emphasis on the organization of proteins in the plasma/cell membrane. Many species belonging to the Eubacteria and Archaea have special membrane domains and/or membrane proliferation, which are vital for different

Plasma membrane organization promotes virulence of the human fungal pathogen Candida albicans.

Science.gov (United States)

Douglas, Lois M; Konopka, James B

2016-03-01

Candida albicans is a human fungal pathogen capable of causing lethal systemic infections. The plasma membrane plays key roles in virulence because it not only functions as a protective barrier, it also mediates dynamic functions including secretion of virulence factors, cell wall synthesis, invasive hyphal morphogenesis, endocytosis, and nutrient uptake. Consistent with this functional complexity, the plasma membrane is composed of a wide array of lipids and proteins. These components are organized into distinct domains that will be the topic of this review. Some of the plasma membrane domains that will be described are known to act as scaffolds or barriers to diffusion, such as MCC/eisosomes, septins, and sites of contact with the endoplasmic reticulum. Other zones mediate dynamic processes, including secretion, endocytosis, and a special region at hyphal tips that facilitates rapid growth. The highly organized architecture of the plasma membrane facilitates the coordination of diverse functions and promotes the pathogenesis of C. albicans.

Plasma membrane organization promotes virulence of the human fungal pathogen Candida albicans

Science.gov (United States)

Douglas, Lois M.; Konopka, James. B.

2017-01-01

Candida albicans is a human fungal pathogen capable of causing lethal systemic infections. The plasma membrane plays key roles in virulence because it not only functions as a protective barrier, it also mediates dynamic functions including secretion of virulence factors, cell wall synthesis, invasive hyphal morphogenesis, endocytosis, and nutrient uptake. Consistent with this functional complexity, the plasma membrane is composed of a wide array of lipids and proteins. These components are organized into distinct domains that will be the topic of this review. Some of the plasma membrane domains that will be described are known to act as scaffolds or barriers to diffusion, such as MCC/eisosomes, septins, and sites of contact with the endoplasmic reticulum. Other zones mediate dynamic processes, including secretion, endocytosis, and a special region at hyphal tips that facilitates rapid growth. The highly organized architecture of the plasma membrane facilitates the coordination of diverse functions and promotes the pathogenesis of C. albicans. PMID:26920878

Development of the specialized integrated circuit for signal readout from micro-strip structures of a coordinate detectors

International Nuclear Information System (INIS)

Aulchenko, V.; Shekhtman, L.; Zhulanov, V.

2015-01-01

The paper presents current status of development of a specialized 64-channel integrated circuit (IC, ASIC) for front-end electronics of coordinate detectors in the Budker INP. The ASIC is produced using 180 nm process. During the recording phase the IC allows integration of short current pulses from strips of a coordinate sensor, and storing of up to 100 corresponding charge values in the analogue memory with minimum time interval of 100 ns. Maximum input charge is equal to 2×10 6 electrons, equivalent noise charge is ∼2.7×10 3 electrons. Conversion of the data, stored in the analogue memory, to digital form is performed by an external ADC during the readout through an analogue multiplexer

Metal–organic frameworks based membranes for liquid separation

KAUST Repository

Li, Xin

2017-11-07

Metal-organic frameworks (MOFs) represent a fascinating class of solid crystalline materials which can be self-assembled in a straightforward manner by the coordination of metal ions or clusters with organic ligands. Owing to their intrinsic porous characteristics, unique chemical versatility and abundant functionalities, MOFs have received substantial attention for diverse industrial applications, including membrane separation. Exciting research activities ranging from fabrication strategies to separation applications of MOF-based membranes have appeared. Inspired by the marvelous achievements of MOF-based membranes in gas separations, liquid separations are also being explored for the purpose of constructing continuous MOFs membranes or MOF-based mixed matrix membranes. Although these are in an emerging stage of vigorous development, most efforts are directed towards improving the liquid separation efficiency with well-designed MOF-based membranes. Therefore, as an increasing trend in membrane separation, the field of MOF-based membranes for liquid separation is highlighted in this review. The criteria for judicious selection of MOFs in fabricating MOF-based membranes are given. Special attention is paid to rational design strategies for MOF-based membranes, along with the latest application progress in the area of liquid separations, such as pervaporation, water treatment, and organic solvent nanofiltration. Moreover, some attractive dual-function applications of MOF-based membranes in the removal of micropollutants, degradation, and antibacterial activity are also reviewed. Finally, we define the remaining challenges and future opportunities in this field. This Tutorial Review provides an overview and outlook for MOF-based membranes for liquid separations. Further development of MOF-based membranes for liquid separation must consider the demands of strict separation standards and environmental safety for industrial application.

Metal-organic frameworks based membranes for liquid separation.

Science.gov (United States)

Li, Xin; Liu, Yuxin; Wang, Jing; Gascon, Jorge; Li, Jiansheng; Van der Bruggen, Bart

2017-11-27

Metal-organic frameworks (MOFs) represent a fascinating class of solid crystalline materials which can be self-assembled in a straightforward manner by the coordination of metal ions or clusters with organic ligands. Owing to their intrinsic porous characteristics, unique chemical versatility and abundant functionalities, MOFs have received substantial attention for diverse industrial applications, including membrane separation. Exciting research activities ranging from fabrication strategies to separation applications of MOF-based membranes have appeared. Inspired by the marvelous achievements of MOF-based membranes in gas separations, liquid separations are also being explored for the purpose of constructing continuous MOFs membranes or MOF-based mixed matrix membranes. Although these are in an emerging stage of vigorous development, most efforts are directed towards improving the liquid separation efficiency with well-designed MOF-based membranes. Therefore, as an increasing trend in membrane separation, the field of MOF-based membranes for liquid separation is highlighted in this review. The criteria for judicious selection of MOFs in fabricating MOF-based membranes are given. Special attention is paid to rational design strategies for MOF-based membranes, along with the latest application progress in the area of liquid separations, such as pervaporation, water treatment, and organic solvent nanofiltration. Moreover, some attractive dual-function applications of MOF-based membranes in the removal of micropollutants, degradation, and antibacterial activity are also reviewed. Finally, we define the remaining challenges and future opportunities in this field. This Tutorial Review provides an overview and outlook for MOF-based membranes for liquid separations. Further development of MOF-based membranes for liquid separation must consider the demands of strict separation standards and environmental safety for industrial application.

45 CFR 1310.23 - Coordinated transportation.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 4 2010-10-01 2010-10-01 false Coordinated transportation. 1310.23 Section 1310... START PROGRAM HEAD START TRANSPORTATION Special Requirements § 1310.23 Coordinated transportation. (a) Each agency providing transportation services must make reasonable efforts to coordinate transportation...

Optineurin: A Coordinator of Membrane-Associated Cargo Trafficking and Autophagy

Directory of Open Access Journals (Sweden)

Thomas A. Ryan

2018-05-01

Full Text Available Optineurin is a multifunctional adaptor protein intimately involved in various vesicular trafficking pathways. Through interactions with an array of proteins, such as myosin VI, huntingtin, Rab8, and Tank-binding kinase 1, as well as via its oligomerisation, optineurin has the ability to act as an adaptor, scaffold, or signal regulator to coordinate many cellular processes associated with the trafficking of membrane-delivered cargo. Due to its diverse interactions and its distinct functions, optineurin is an essential component in a number of homeostatic pathways, such as protein trafficking and organelle maintenance. Through the binding of polyubiquitinated cargoes via its ubiquitin-binding domain, optineurin also serves as a selective autophagic receptor for the removal of a wide range of substrates. Alternatively, it can act in an ubiquitin-independent manner to mediate the clearance of protein aggregates. Regarding its disease associations, mutations in the optineurin gene are associated with glaucoma and have more recently been found to correlate with Paget’s disease of bone and amyotrophic lateral sclerosis (ALS. Indeed, ALS-associated mutations in optineurin result in defects in neuronal vesicular localisation, autophagosome–lysosome fusion, and secretory pathway function. More recent molecular and functional analysis has shown that it also plays a role in mitophagy, thus linking it to a number of other neurodegenerative conditions, such as Parkinson’s. Here, we review the role of optineurin in intracellular membrane trafficking, with a focus on autophagy, and describe how upstream signalling cascades are critical to its regulation. Current data and contradicting reports would suggest that optineurin is an important and selective autophagy receptor under specific conditions, whereby interplay, synergy, and functional redundancy with other receptors occurs. We will also discuss how dysfunction in optineurin-mediated pathways may lead

MPK-1 ERK Controls Membrane Organization in C. elegans Oogenesis via a Sex-Determination Module

OpenAIRE

Arur, Swathi; Ohmachi, Mitsue; Berkseth, Matt; Nayak, Sudhir; Hansen, David; Zarkower, David; Schedl, Tim

2011-01-01

Tissues that generate specialized cell-types in a production line must coordinate developmental mechanisms with physiological demand, although how this occurs is largely unknown. In the C. elegans hermaphrodite, the developmental sex-determination cascade specifies gamete sex in the distal germline, while physiological sperm signaling activates MPK-1/ERK in the proximal germline to control plasma membrane biogenesis/organization during oogenesis. We discovered repeated utilization of a self-c...

Care Coordination for Children with Complex Special Health Care Needs: The Value of the Advanced Practice Nurse’s Enhanced Scope of Knowledge and Practice

Science.gov (United States)

Looman, Wendy S.; Presler, Elizabeth; Erickson, Mary M.; Garwick, Ann E.; Cady, Rhonda G.; Kelly, Anne M.; Finkelstein, Stanley M.

2012-01-01

Efficiency and effectiveness of care coordination depends on a match between the needs of the population and the skills, scope of practice, and intensity of services provided by the care coordinator. There is limited existing literature that addresses the relevance of the APN role as a fit for coordination of care for children with SHCN. The objective of this paper is to describe the value of the advanced practice nurse’s (APN’s) enhanced scope of knowledge and practice for relationship-based care coordination in healthcare homes that serve children with complex special health care needs (SHCN). The TeleFamilies project is provided as an example of the integration of an APN care coordinator in a healthcare home for children with SHCN. PMID:22560803

Care coordination, medical complexity, and unmet need for prescription medications among children with special health care needs.

Science.gov (United States)

Aboneh, Ephrem A; Chui, Michelle A

Children with special health care needs (CSHCN) have multiple unmet health care needs including that of prescription medications. The objectives of this study were twofold: 1) to quantify and compare unmet needs for prescription medications for subgroups of CSHCN without and with medical complexity (CMC)-those who have multiple, chronic, and complex medical conditions associated with severe functional limitations and high utilization of health care resources, and 2) to describe its association with receipt of effective care coordination services and level of medical complexity. A secondary data analysis of the 2009/2010 National Survey of CSHCN, a nationally representative telephone survey of parents of CSHCN, was conducted. Logistic regression models were constructed to determine associations between unmet need for prescription medications and medical complexity and care coordination for families of CSHCN, while controlling for demographic variables such as race, insurance, education level, and household income. Analyses accounted for the complex survey design and sampling weights. CMC represented about 3% of CSHCN. CMC parents reported significantly more unmet need for prescription medications and care coordination (4%, 68%), compared to Non-CMC parents (2%, 40%). Greater unmet need for prescription medications was associated with unmet care coordination (adjusted OR 3.81; 95% CI: 2.70-5.40) and greater medical complexity (adjusted OR 2.01; 95% CI: 1.00-4.03). Traditional care coordination is primarily facilitated by nurses and nurse practitioners with little formal training in medication management. However, pharmacists are rarely part of the CSHCN care coordination model. As care delivery models for these children evolve, and given the complexity of and numerous transitions of care for these patients, pharmacists can play an integral role to improve unmet needs for prescription medications. Copyright © 2016 Elsevier Inc. All rights reserved.

A cellular backline: specialization of host membranes for defence.

Science.gov (United States)

Faulkner, Christine

2015-03-01

In plant-pathogen interactions, the host plasma membrane serves as a defence front for pathogens that invade from the extracellular environment. As such, the lipid bilayer acts as a scaffold that targets and delivers defence responses to the site of attack. During pathogen infection, numerous changes in plasma membrane composition, organization, and structure occur. There is increasing evidence that this facilitates the execution of a variety of responses, highlighting the regulatory role membranes play in cellular responses. Membrane microdomains such as lipid rafts are hypothesized to create signalling platforms for receptor signalling in response to pathogen perception and for callose synthesis. Further, the genesis of pathogen-associated structures such as papillae and the extra-haustorial membrane necessitates polarization of membranes and membrane trafficking pathways. Unlocking the mechanisms by which this occurs will enable greater understanding of how targeted defences, some of which result in resistance, are executed. This review will survey some of the changes that occur in host membranes during pathogen attack and how these are associated with the generation of defence responses. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Coordinating abilities in structure of special preparation of combat athletes

Directory of Open Access Journals (Sweden)

Klymenko A.I.

2010-03-01

Full Text Available Development tendency of modern sport assumes high competition and as a result, training and competitive pressure. This requires from the coach to search for new methods of increasing effectiveness of the training process without increasing the pressure volume and intensiveness. One of the ways of solving this problem is the development of a method of increasing coordinating abilities. Several types of coordinating abilities of wrestlers. Deals with methodical peculiarities or perfection and means of increasing coordinating of sambo.

MPK-1 ERK controls membrane organization in C. elegans oogenesis via a sex-determination module.

Science.gov (United States)

Arur, Swathi; Ohmachi, Mitsue; Berkseth, Matt; Nayak, Sudhir; Hansen, David; Zarkower, David; Schedl, Tim

2011-05-17

Tissues that generate specialized cell types in a production line must coordinate developmental mechanisms with physiological demand, although how this occurs is largely unknown. In the Caenorhabditis elegans hermaphrodite, the developmental sex-determination cascade specifies gamete sex in the distal germline, while physiological sperm signaling activates MPK-1/ERK in the proximal germline to control plasma membrane biogenesis and organization during oogenesis. We discovered repeated utilization of a self-contained negative regulatory module, consisting of NOS-3 translational repressor, FEM-CUL-2 (E3 ubiquitin ligase), and TRA-1 (Gli transcriptional repressor), which acts both in sex determination and in physiological demand control of oogenesis, coordinating these processes. In the distal germline, where MPK-1 is not activated, TRA-1 represses the male fate as NOS-3 functions in translational repression leading to inactivation of the FEM-CUL-2 ubiquitin ligase. In the proximal germline, sperm-dependent physiological MPK-1 activation results in phosphorylation-based inactivation of NOS-3, FEM-CUL-2-mediated degradation of TRA-1 and the promotion of membrane organization during oogenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

Vaginal epithelial cells regulate membrane adhesiveness to co-ordinate bacterial adhesion.

Science.gov (United States)

Younes, Jessica A; Klappe, Karin; Kok, Jan Willem; Busscher, Henk J; Reid, Gregor; van der Mei, Henny C

2016-04-01

Vaginal epithelium is colonized by different bacterial strains and species. The bacterial composition of vaginal biofilms controls the balance between health and disease. Little is known about the relative contribution of the epithelial and bacterial cell surfaces to bacterial adhesion and whether and how adhesion is regulated over cell membrane regions. Here, we show that bacterial adhesion forces with cell membrane regions not located above the nucleus are stronger than with regions above the nucleus both for vaginal pathogens and different commensal and probiotic lactobacillus strains involved in health. Importantly, adhesion force ratios over membrane regions away from and above the nucleus coincided with the ratios between numbers of adhering bacteria over both regions. Bacterial adhesion forces were dramatically decreased by depleting the epithelial cell membrane of cholesterol or sub-membrane cortical actin. Thus, epithelial cells can regulate membrane regions to which bacterial adhesion is discouraged, possibly to protect the nucleus. © 2015 John Wiley & Sons Ltd.

The plasma membrane proteome of germinating barley embryos

DEFF Research Database (Denmark)

Hynek, Radovan; Svensson, Birte; Jensen, O.N.

2009-01-01

Cereal seed germination involves a complex coordination between different seed tissues. Plasma membranes must play crucial roles in coordination and execution of germination; however, very little is known about seed plasma membrane proteomes due to limited tissue amounts combined...... with amphiphilicity and low abundance of membrane proteins. A fraction enriched in plasma membranes was prepared from embryos dissected from 18 h germinated barley seeds using aqueous two-phase partitioning. Reversed-phase chromatography on C-4 resin performed in micro-spin columns with stepwise elution by 2-propanol...... was used to reduce soluble protein contamination and enrich for hydrophobic proteins. Sixty-one proteins in 14 SDS-PAGE bands were identified by LC-MS/MS and database searches. The identifications provide new insight into the plasma membrane functions in seed germination....

Optimal stochastic coordinated scheduling of proton exchange membrane fuel cell-combined heat and power, wind and photovoltaic units in micro grids considering hydrogen storage

International Nuclear Information System (INIS)

Bornapour, Mosayeb; Hooshmand, Rahmat-Allah; Khodabakhshian, Amin; Parastegari, Moein

2017-01-01

Highlights: •Stochastic model is proposed for coordinated scheduling of renewable energy sources. •The effect of combined heat and power is considered. •Hydrogen storage is considered for fuel cells. •Maximizing profits of micro grid is considered as objective function. •Considering the uncertainties of problem lead to profit increasing. -- Abstract: Nowadays, renewable energy sources and combined heat and power units are extremely used in micro grids, so it is necessary to schedule these units to improve the performance of the system. In this regard, a stochastic model is proposed in this paper to schedule proton exchange membrane fuel cell-combined heat and power, wind turbines, and photovoltaic units coordinately in a micro grid while considering hydrogen storage. Hydrogen storage strategy is considered for the operation of proton exchange membrane fuel cell-combined heat and power units. To consider stochastic generation of renewable energy source units in this paper, a scenario-based method is used. In this method, the uncertainties of electrical market price, the wind speed, and solar irradiance are considered. This stochastic scheduling problem is a mixed integer- nonlinear programming which considers the proposed objective function and variables of coordinated scheduling of PEMFC-CHP, wind turbines and photovoltaic units. It also considers hydrogen storage strategy and converts it to a mixed integer nonlinear problem. In this study a modified firefly algorithm is used to solve the problem. This method is examined on modified 33-bus distributed network as a MG for its performance.

An Adaptable Spectrin/Ankyrin-Based Mechanism for Long-Range Organization of Plasma Membranes in Vertebrate Tissues.

Science.gov (United States)

Bennett, Vann; Lorenzo, Damaris N

2016-01-01

Ankyrins are membrane-associated proteins that together with their spectrin partners are responsible for micron-scale organization of vertebrate plasma membranes, including those of erythrocytes, excitable membranes of neurons and heart, lateral membrane domains of columnar epithelial cells, and striated muscle. Ankyrins coordinate functionally related membrane transporters and cell adhesion proteins (15 protein families identified so far) within plasma membrane compartments through independently evolved interactions of intrinsically disordered sequences with a highly conserved peptide-binding groove formed by the ANK repeat solenoid. Ankyrins are coupled to spectrins, which are elongated organelle-sized proteins that form mechanically resilient arrays through cross-linking by specialized actin filaments. In addition to protein interactions, cellular targeting and assembly of spectrin/ankyrin domains also critically depend on palmitoylation of ankyrin-G by aspartate-histidine-histidine-cysteine 5/8 palmitoyltransferases, as well as interaction of beta-2 spectrin with phosphoinositide lipids. These lipid-dependent spectrin/ankyrin domains are not static but are locally dynamic and determine membrane identity through opposing endocytosis of bulk lipids as well as specific proteins. A partnership between spectrin, ankyrin, and cell adhesion molecules first emerged in bilaterians over 500 million years ago. Ankyrin and spectrin may have been recruited to plasma membranes from more ancient roles in organelle transport. The basic bilaterian spectrin-ankyrin toolkit markedly expanded in vertebrates through gene duplications combined with variation in unstructured intramolecular regulatory sequences as well as independent evolution of ankyrin-binding activity by ion transporters involved in action potentials and calcium homeostasis. In addition, giant vertebrate ankyrins with specialized roles in axons acquired new coding sequences by exon shuffling. We speculate that

Evidence of hemispheric specialization in marmosets (Callithrix penicillata using tympanic membrane thermometry

Directory of Open Access Journals (Sweden)

C. Tomaz

2003-07-01

Full Text Available Recent studies have employed tympanic thermometry to assess lateralization of cognitive and emotional functions in primates. However, no studies using this technique have investigated the possibility of hemispheric specialization in New World monkeys. Therefore, the aim of the present study was to investigate tympanic membrane (TM temperature asymmetries and their possible correlation with stress responses in marmosets (Callithrix penicillata. Infrared TM thermometry was completed bilaterally in 24 animals (14 males and 10 females during a stressful situation of capture and restraint. There were no significant differences between gender. A significant negative correlation was observed between TM temperature of the right ear and the number of captures (r = -0.633; P<0.001. Subjects with a more frequent previous history of captures (5 to 9 captures; N = 11 showed lower TM temperature when compared to those with fewer previous captures (1 to 4 captures; N = 13. No differences were observed for the left TM temperature. These results suggest that under intense emotional challenge (capture and restraint there is a stronger activation of the neural structures situated in the right brain hemisphere. Taken together, the data reveal for the first time evidence of hemispheric specialization in emotional physiological processing in a New World monkey.

A review on radiation damage of erythrocyte membranes

International Nuclear Information System (INIS)

Wang Junling; Wang Weidong; Qin Guangyong

2007-01-01

Biomembrane has very important biological function. Its damage will seriously disturb the directivity, the orderly nature and coordination of cell metabolism, and finally causes the cell death. This paper reviewed the effects of radiation damage on erythrocyte membrane in membrane composition, membrane function and oxidation resistance system. (authors)

Chapter 6: cubic membranes the missing dimension of cell membrane organization.

Science.gov (United States)

Almsherqi, Zakaria A; Landh, Tomas; Kohlwein, Sepp D; Deng, Yuru

2009-01-01

Biological membranes are among the most fascinating assemblies of biomolecules: a bilayer less than 10 nm thick, composed of rather small lipid molecules that are held together simply by noncovalent forces, defines the cell and discriminates between "inside" and "outside", survival, and death. Intracellular compartmentalization-governed by biomembranes as well-is a characteristic feature of eukaryotic cells, which allows them to fulfill multiple and highly specialized anabolic and catabolic functions in strictly controlled environments. Although cellular membranes are generally visualized as flat sheets or closely folded isolated objects, multiple observations also demonstrate that membranes may fold into "unusual", highly organized structures with 2D or 3D periodicity. The obvious correlation of highly convoluted membrane organizations with pathological cellular states, for example, as a consequence of viral infection, deserves close consideration. However, knowledge about formation and function of these highly organized 3D periodic membrane structures is scarce, primarily due to the lack of appropriate techniques for their analysis in vivo. Currently, the only direct way to characterize cellular membrane architecture is by transmission electron microscopy (TEM). However, deciphering the spatial architecture solely based on two-dimensionally projected TEM images is a challenging task and prone to artifacts. In this review, we will provide an update on the current progress in identifying and analyzing 3D membrane architectures in biological systems, with a special focus on membranes with cubic symmetry, and their potential role in physiological and pathophysiological conditions. Proteomics and lipidomics approaches in defined experimental cell systems may prove instrumental to understand formation and function of 3D membrane morphologies.

The plant membrane surrounding powdery mildew haustoria shares properties with the endoplasmic reticulum membrane

DEFF Research Database (Denmark)

Kwaaitaal, Mark Adrianus Cornelis J; Nielsen, Mads Eggert; Böhlenius, Henrik

2017-01-01

Many filamentous plant pathogens place specialized feeding structures, called haustoria, inside living host cells. As haustoria grow, they are believed to manipulate plant cells to generate a specialized, still enigmatic extrahaustorial membrane (EHM) around them. Here, we focused on revealing...... properties of the EHM. With the help of membranespecific dyes and transient expression of membrane-associated proteins fused to fluorescent tags, we studied the nature of the EHM generated by barley leaf epidermal cells around powdery mildew haustoria. Observations suggesting that endoplasmic reticulum (ER...... that it is not a continuum of the ER. Furthermore, GDP-locked Sar1 and a nucleotide-free RabD2a, which block ER to Golgi exit, did not hamper haustorium formation. These results indicated that the EHM shares features with the plant ER membrane, but that the EHM membrane is not dependent on conventional secretion...

Design of membrane pressure indicators with strain gages

International Nuclear Information System (INIS)

Haberzettl, G.

1979-01-01

A special type of pressure indicators, more or less well known under the name of 'membrane pressure indicators' is dealt with. In principle, they consist of a pipe socket which is open at one end and sealed by the 'membrane' at the other end. In case of internal pressure from the open side, the membrane will begin to arch. This arch, which is proportional to the internal pressure, is measured by suitable methods. A special form of strain ganges, so-called 'membrane pressure roses' have turned out to be particularly suitable here. The article gives general guidelines for the construction of membrane pressure indicators. (orig./HT) [de

Reliability of functioning and reserves of system, controlling movements with different coordination structure of special health group girl students in physical education process

Directory of Open Access Journals (Sweden)

A.A. Pryimakov

2017-04-01

Full Text Available Purpose: to study reliability of functioning and reserves of system, controlling movements with different coordination structure of special health group girl students (low health level in physical education process. Material: in the research special health group girl students (n=136, age 17-19 participated. They were divided into 2 groups - control and experimental. The program, directed to increase reliability and reserves of system controlling movements, was realized. It was based on physical exercises of complicated coordination with novelty elements, which were fulfilled under musical accompaniment. The research continued one academic year. Results: in girl students with health problems we registered higher differential thresholds, when reproducing local movements in complicated conditions. They used visual and hearing feedback channels for informing brain’s programming areas about made mistakes. They were worse teachable in training accurate movements. These girl students have less expressed compensation reserves under impact of hindering factors and interferences. It can be interpreted as non-specific crisscross negative response to motor functional system in case of health problems. All these determine reduction of reserve potentials of motor control system. Conclusions: The main reserve potentials’ criteria of control over different coordination structure movements are: quickness of passing to program mechanism of fine movements’ regulation in stable conditions of functioning; power and effectiveness of compensatory reactions, ensuring interference immunity of system, controlling movements under interfering factors; reliability of maintaining movements’ qualitative parameters in optimal range under interfering factors; reduction of sensor interconnections in stable functioning conditions.

Special geometry

International Nuclear Information System (INIS)

Strominger, A.

1990-01-01

A special manifold is an allowed target manifold for the vector multiplets of D=4, N=2 supergravity. These manifolds are of interest for string theory because the moduli spaces of Calabi-Yau threefolds and c=9, (2,2) conformal field theories are special. Previous work has given a local, coordinate-dependent characterization of special geometry. A global description of special geometries is given herein, and their properties are studied. A special manifold M of complex dimension n is characterized by the existence of a holomorphic Sp(2n+2,R)xGL(1,C) vector bundle over M with a nowhere-vanishing holomorphic section Ω. The Kaehler potential on M is the logarithm of the Sp(2n+2,R) invariant norm of Ω. (orig.)

The formation of endosymbiotic membrane compartments: membrane identity markers and the regulation of vesicle trafficking

NARCIS (Netherlands)

Ivanov, S.

2012-01-01

In symbiosis of plants and arbuscular mycorrhizal fungi as well as in rhizobium-legume symbiosis the microbes are hosted intracellularly, inside specialized membrane compartments of the host. These membrane compartments are morphologically different but similar in function, since they control

Activation of interfacial enzymes at membrane surfaces

DEFF Research Database (Denmark)

Mouritsen, Ole G.; Andresen, Thomas Lars; Halperin, Avi

2006-01-01

A host of water-soluble enzymes are active at membrane surfaces and in association with membranes. Some of these enzymes are involved in signalling and in modification and remodelling of the membranes. A special class of enzymes, the phospholipases, and in particular secretory phospholipase A2 (s...

Integrable structure in discrete shell membrane theory.

Science.gov (United States)

Schief, W K

2014-05-08

We present natural discrete analogues of two integrable classes of shell membranes. By construction, these discrete shell membranes are in equilibrium with respect to suitably chosen internal stresses and external forces. The integrability of the underlying equilibrium equations is proved by relating the geometry of the discrete shell membranes to discrete O surface theory. We establish connections with generalized barycentric coordinates and nine-point centres and identify a discrete version of the classical Gauss equation of surface theory.

Membrane microdomains, rafts, and detergent-resistant membranes in plants and fungi.

Science.gov (United States)

Malinsky, Jan; Opekarová, Miroslava; Grossmann, Guido; Tanner, Widmar

2013-01-01

The existence of specialized microdomains in plasma membranes, postulated for almost 25 years, has been popularized by the concept of lipid or membrane rafts. The idea that detergent-resistant membranes are equivalent to lipid rafts, which was generally abandoned after a decade of vigorous data accumulation, contributed to intense discussions about the validity of the raft concept. The existence of membrane microdomains, meanwhile, has been verified by unequivocal independent evidence. This review summarizes the current state of research in plants and fungi with respect to common aspects of both kingdoms. In these organisms, principally immobile microdomains large enough for microscopic detection have been visualized. These microdomains are found in the context of cell-cell interactions (plant symbionts and pathogens), membrane transport, stress, and polarized growth, and the data corroborate at least three mechanisms of formation. As documented in this review, modern methods of visualization of lateral membrane compartments are also able to uncover the functional relevance of membrane microdomains.

An innovative Oklahoma program to coordinate interdisciplinary and interagency services for children with special healthcare needs at a county level.

Science.gov (United States)

Wolraich, Mark; Lockhart, Jennifer; Worley, Louis

2013-03-01

Children and youth with special health care needs (CYSHCN) and their families often require multiple services from multiple providers in order to meet their needs. The Sooner SUCCESS (State Unified Children's Comprehensive Exemplary Services for Special Needs), was developed based on a complex adaptive systems approach allowing local coalitions to address their unique needs. Sooner SUCCESS provides support to families and service providers at the community level including a broad range of supports from simply helping a family identify and access a service that already exists to innovatively marshaling generic resources to meet a unique need. The program uses these family support activities coupled with the Community Needs Assessment to identify local service needs encouraging community capacity building by coordinating the efforts of the health, mental health, social and education systems to identify service gaps and develop community-based strategies to fill those gaps.

Cluster algebras in scattering amplitudes with special 2D kinematics

Energy Technology Data Exchange (ETDEWEB)

Torres, Marcus A.C. [Institut de Physique Theorique, CEA-Saclay, Gif-sur-Yvette Cedex (France)

2014-02-15

We study the cluster algebra of the kinematic configuration space Conf{sub n}(P{sup 3}P3) of an n-particle scattering amplitude restricted to the special 2D kinematics. We found that the n-point two-loop MHVremainder function in special 2D kinematics depends on a selection of the X-coordinates that are part of a special structure of the cluster algebra related to snake triangulations of polygons. This structure forms a necklace of hypercube beads in the corresponding Stasheff polytope. Furthermore at n = 12, the cluster algebra and the selection of theX-coordinates in special2Dkinematics replicates the cluster algebra and the selection of X-coordinates of the n = 6 two-loop MHV amplitude in 4D kinematics. (orig.)

Metal–organic frameworks based membranes for liquid separation

KAUST Repository

Li, Xin; Liu, Yuxin; Wang, Jing; Gascon, Jorge; Li, Jiansheng; Van der Bruggen, Bart

2017-01-01

, the field of MOF-based membranes for liquid separation is highlighted in this review. The criteria for judicious selection of MOFs in fabricating MOF-based membranes are given. Special attention is paid to rational design strategies for MOF-based membranes

Developments in special geometry

International Nuclear Information System (INIS)

Mohaupt, Thomas; Vaughan, Owen

2012-01-01

We review the special geometry of N = 2 supersymmetric vector and hypermultiplets with emphasis on recent developments and applications. A new formulation of the local c-map based on the Hesse potential and special real coordinates is presented. Other recent developments include the Euclidean version of special geometry, and generalizations of special geometry to non-supersymmetric theories. As applications we discuss the proof that the local r-map and c-map preserve geodesic completeness, and the construction of four- and five-dimensional static solutions through dimensional reduction over time. The shared features of the real, complex and quaternionic version of special geometry are stressed throughout.

Issues in assessing the cost-effectiveness of coordinated DSM programs

International Nuclear Information System (INIS)

Hill, L.J.; Brown, M.A.

1995-01-01

Coordinated demand-side management (DSM) programs, co-administered by government agencies and electric and gas utilities, are likely to grow in importance in the coming years. Because of the unique features of these types of DSM programs, special care must be taken in assessing their cost-effectiveness. In this paper, we discuss these features, suggest how standard cost-effectiveness measures must be adapted to accommodate them, and show how important these adaptations are in assessing the cost-effectiveness of coordinated programs. At first, we use a least-cost, financial approach. The discussion indicates that failure to account properly for the special features of coordinated programs materially affects estimates of cost-effectiveness and, in extreme cases, may lead to rejection of otherwise cost-effective programs. Then extending the analysis to include economic factors, we speculate that most types of coordinated programs are more attractive than when evaluated on a financial basis. (author)

The actin homologue MreB organizes the bacterial cell membrane

NARCIS (Netherlands)

Strahl, H.; Burmann, F.; Hamoen, L.W.

2014-01-01

The eukaryotic cortical actin cytoskeleton creates specific lipid domains, including lipid rafts, which determine the distribution of many membrane proteins. Here we show that the bacterial actin homologue MreB displays a comparable activity. MreB forms membrane-associated filaments that coordinate

Track membranes, production, properties, applications

International Nuclear Information System (INIS)

Oganesjan, Yu.Ts.

1994-01-01

The problems of producing track membranes on heavy ion beams of the Flerov Laboratory are considered. The parameters of the running accelerators and equipment for the irradiation of polymer foils are presented. The process of production of track membranes based on different polymeric materials and various applications of the membranes are described. Special attention is given to the principally new applications and devices developed at the Laboratory. This report presents the results obtained by a big group of scientists and engineers working in the field of elaboration, investigation and application of track membranes (author). 21 refs, 20 figs, 1 tab

Future in actinoids coordination chemistry

International Nuclear Information System (INIS)

Kitazawa, Takafumi

2006-01-01

Actinoids coordination chemistry is concerned with spent nuclear fuel reprocessing, specifically with solid-state chemistry of nuclear fuels, separation process with radioactive substances, and geological disposal of high-level radioactive substances. In the 21st century, accumulation of minor actinides, Np, Am, Cm, and others will be realized according with the present program of nuclear energy development. The present article briefly introduces general properties of actinide elements, followed by their coordination chemistry compared with rare earths coordination chemistry. Special facility needed to treat actinoids as well as their chemistry is briefly explained, together with the specific experimental apparatus such as X-ray Absorption Fine Structure (XAFS) and time-resolved laser-induced fluorescence spectrometry (TRLFS) with synchrotron radiation facilities. The effect of coordination with actinoids in the environment chemistry is important in underground disposal of high-level radioactive wastes. For theoretical analysis of the results with actinoids chemistry, relativistic calculation is needed. (S. Ohno)

Patterns of coordinated cortical remodeling during adolescence and their associations with functional specialization and evolutionary expansion.

Science.gov (United States)

Sotiras, Aristeidis; Toledo, Jon B; Gur, Raquel E; Gur, Ruben C; Satterthwaite, Theodore D; Davatzikos, Christos

2017-03-28

During adolescence, the human cortex undergoes substantial remodeling to support a rapid expansion of behavioral repertoire. Accurately quantifying these changes is a prerequisite for understanding normal brain development, as well as the neuropsychiatric disorders that emerge in this vulnerable period. Past accounts have demonstrated substantial regional heterogeneity in patterns of brain development, but frequently have been limited by small samples and analytics that do not evaluate complex multivariate imaging patterns. Capitalizing on recent advances in multivariate analysis methods, we used nonnegative matrix factorization (NMF) to uncover coordinated patterns of cortical development in a sample of 934 youths ages 8-20, who completed structural neuroimaging as part of the Philadelphia Neurodevelopmental Cohort. Patterns of structural covariance (PSCs) derived by NMF were highly reproducible over a range of resolutions, and differed markedly from common gyral-based structural atlases. Moreover, PSCs were largely symmetric and showed correspondence to specific large-scale functional networks. The level of correspondence was ordered according to their functional role and position in the evolutionary hierarchy, being high in lower-order visual and somatomotor networks and diminishing in higher-order association cortex. Furthermore, PSCs showed divergent developmental associations, with PSCs in higher-order association cortex networks showing greater changes with age than primary somatomotor and visual networks. Critically, such developmental changes within PSCs were significantly associated with the degree of evolutionary cortical expansion. Together, our findings delineate a set of structural brain networks that undergo coordinated cortical thinning during adolescence, which is in part governed by evolutionary novelty and functional specialization.

Formation and Regulation of Mitochondrial Membranes

Directory of Open Access Journals (Sweden)

Laila Cigana Schenkel

2014-01-01

Full Text Available Mitochondrial membrane phospholipids are essential for the mitochondrial architecture, the activity of respiratory proteins, and the transport of proteins into the mitochondria. The accumulation of phospholipids within mitochondria depends on a coordinate synthesis, degradation, and trafficking of phospholipids between the endoplasmic reticulum (ER and mitochondria as well as intramitochondrial lipid trafficking. Several studies highlight the contribution of dietary fatty acids to the remodeling of phospholipids and mitochondrial membrane homeostasis. Understanding the role of phospholipids in the mitochondrial membrane and their metabolism will shed light on the molecular mechanisms involved in the regulation of mitochondrial function and in the mitochondrial-related diseases.

G protein-membrane interactions II: Effect of G protein-linked lipids on membrane structure and G protein-membrane interactions.

Science.gov (United States)

Casas, Jesús; Ibarguren, Maitane; Álvarez, Rafael; Terés, Silvia; Lladó, Victoria; Piotto, Stefano P; Concilio, Simona; Busquets, Xavier; López, David J; Escribá, Pablo V

2017-09-01

G proteins often bear myristoyl, palmitoyl and isoprenyl moieties, which favor their association with the membrane and their accumulation in G Protein Coupled Receptor-rich microdomains. These lipids influence the biophysical properties of membranes and thereby modulate G protein binding to bilayers. In this context, we showed here that geranylgeraniol, but neither myristate nor palmitate, increased the inverted hexagonal (H II ) phase propensity of phosphatidylethanolamine-containing membranes. While myristate and palmitate preferentially associated with phosphatidylcholine membranes, geranylgeraniol favored nonlamellar-prone membranes. In addition, Gαi 1 monomers had a higher affinity for lamellar phases, while Gβγ and Gαβγ showed a marked preference for nonlamellar prone membranes. Moreover, geranylgeraniol enhanced the binding of G protein dimers and trimers to phosphatidylethanolamine-containing membranes, yet it decreased that of monomers. By contrast, both myristate and palmitate increased the Gαi 1 preference for lamellar membranes. Palmitoylation reinforced the binding of the monomer to PC membranes and myristoylation decreased its binding to PE-enriched bilayer. Finally, binding of dimers and trimers to lamellar-prone membranes was decreased by palmitate and myristate, but it was increased in nonlamellar-prone bilayers. These results demonstrate that co/post-translational G protein lipid modifications regulate the membrane lipid structure and that they influence the physico-chemical properties of membranes, which in part explains why G protein subunits sort to different plasma membrane domains. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá. Copyright © 2017 Elsevier B.V. All rights reserved.

Spatio-temporal remodeling of functional membrane microdomains organizes the signaling networks of a bacterium.

Directory of Open Access Journals (Sweden)

Johannes Schneider

2015-04-01

Full Text Available Lipid rafts are membrane microdomains specialized in the regulation of numerous cellular processes related to membrane organization, as diverse as signal transduction, protein sorting, membrane trafficking or pathogen invasion. It has been proposed that this functional diversity would require a heterogeneous population of raft domains with varying compositions. However, a mechanism for such diversification is not known. We recently discovered that bacterial membranes organize their signal transduction pathways in functional membrane microdomains (FMMs that are structurally and functionally similar to the eukaryotic lipid rafts. In this report, we took advantage of the tractability of the prokaryotic model Bacillus subtilis to provide evidence for the coexistence of two distinct families of FMMs in bacterial membranes, displaying a distinctive distribution of proteins specialized in different biological processes. One family of microdomains harbors the scaffolding flotillin protein FloA that selectively tethers proteins specialized in regulating cell envelope turnover and primary metabolism. A second population of microdomains containing the two scaffolding flotillins, FloA and FloT, arises exclusively at later stages of cell growth and specializes in adaptation of cells to stationary phase. Importantly, the diversification of membrane microdomains does not occur arbitrarily. We discovered that bacterial cells control the spatio-temporal remodeling of microdomains by restricting the activation of FloT expression to stationary phase. This regulation ensures a sequential assembly of functionally specialized membrane microdomains to strategically organize signaling networks at the right time during the lifespan of a bacterium.

Separable coordinates and particle creation I: the klein-Gordon equation

International Nuclear Information System (INIS)

Costa, Isaias

1987-01-01

A very simple derivation of the 10 orthogonal coordinate systems where the Klein-Gordon equation separates is presented. It is based on the conformal structure of the two dimensional Minkowski space. Horizons, proper time and acceleration of abserves that follow the time coordinate line, as well as other physical properties of the systems, are obtained. The relevance of these coordinates is discussed, specially in the context of quantum field theory in curved space. (author) [pt

The actin homologue MreB organizes the bacterial cell membrane

OpenAIRE

Strahl, Henrik; Bürmann, Frank; Hamoen, Leendert W.

2014-01-01

The eukaryotic cortical actin cytoskeleton creates specific lipid domains, including lipid rafts, which determine the distribution of many membrane proteins. Here we show that the bacterial actin homologue MreB displays a comparable activity. MreB forms membrane-associated filaments that coordinate bacterial cell wall synthesis. We noticed that the MreB cytoskeleton influences fluorescent staining of the cytoplasmic membrane. Detailed analyses combining an array of mutants, using specific lip...

Cellulose microfibril deposition: coordinated activity at the plant plasma membrane

NARCIS (Netherlands)

Lindeboom, J.J.; Mulder, B.; Vos, J.W.; Ketelaar, M.J.; Emons, A.M.C.

2008-01-01

Plant cell wall production is a membrane-bound process. Cell walls are composed of cellulose microfibrils, embedded inside a matrix of other polysaccharides and glycoproteins. The cell wall matrix is extruded into the existing cell wall by exocytosis. This same process also inserts the cellulose

Mechanics of Lipid Bilayer Membranes

Science.gov (United States)

Powers, Thomas R.

All cells have membranes. The plasma membrane encapsulates the cell's interior, acting as a barrier against the outside world. In cells with nuclei (eukaryotic cells), membranes also form internal compartments (organelles) which carry out specialized tasks, such as protein modification and sorting in the case of the Golgi apparatus, and ATP production in the case of mitochondria. The main components of membranes are lipids and proteins. The proteins can be channels, carriers, receptors, catalysts, signaling molecules, or structural elements, and typically contribute a substantial fraction of the total membrane dry weight. The equilibrium properties of pure lipid membranes are relatively well-understood, and will be the main focus of this article. The framework of elasticity theory and statistical mechanics that we will develop will serve as the foundation for understanding biological phenomena such as the nonequilibrium behavior of membranes laden with ion pumps, the role of membrane elasticity in ion channel gating, and the dynamics of vesicle fission and fusion. Understanding the mechanics of lipid membranes is also important for drug encapsulation and delivery.

Laccase Immobilization by Chelated Metal Ion Coordination Chemistry

Directory of Open Access Journals (Sweden)

Qingqing Wang

2014-09-01

Full Text Available In this work, amidoxime polyacrylonitrile (AOPAN nanofibrous membrane was prepared by a reaction between PAN nanofibers and hydroxylamine hydrochloride. The AOPAN nanofibrous membranes were used for four metal ions (Fe3+, Cu2+, Ni2+, Cd2+ chelation under different conditions. Further, the competition of different metal ions coordinating with AOPAN nanofibrous membrane was also studied. The AOPAN chelated with individual metal ion (Fe3+, Cu2+, Ni2+, Cd2+ and also the four mixed metal ions were further used for laccase (Lac immobilization. Compared with free laccase, the immobilized laccase showed better resistance to pH and temperature changes as well as improved storage stability. Among the four individual metal ion chelated membranes, the stability of the immobilized enzymes generally followed the order as Fe–AOPAN–Lac > Cu–AOPAN–Lac > Ni–AOPAN–Lac > Cd–AOPAN–Lac. In addition, the immobilized enzyme on the carrier of AOPAN chelated with four mixed metal ions showed the best properties.

Coordinate asymptotics of the (3→3) wave functions for a three charged particle system

International Nuclear Information System (INIS)

Merkur'ev, S.P.

1977-01-01

Coordinate asymptotics of the (3 → 3) wave functions for three particles system with Coulomb interaction in the scattering problem is plotted. (3 → 3) and (3 → 2) process cases are considered, when the particles are not connected at the initial state. For coordinate asymptotics plotting the basis functions are used which meet Schroedinger equation in the eikonal approximation. The wave functions coordinate asymptotics plotting method is described far from special directions. Wave function asymptotical form is studied in the range of special directions and (3 → 3) scattering amplitude singularities are described. All data are given in accordance with the system with 2 charged particles only. The model in question is of special interest because of the described ppn system the studying of which is of great importance in nuclear physics. Final formulae are discussed for the most general case of three charged particles. Boundary problems for Schroedinger equation are shown to give the only way of definition for the (3 → 3) wave functions. It is pointed out that in special directions wave function coordinate asymptotics is presented with accuracy that gives the possibility to set such a boundary problem

[Germ cell membrane lipids in spermatogenesis].

Science.gov (United States)

Wang, Ting; Shi, Xiao; Quan, Song

2016-05-01

Spermatogenesis is a complex developmental process in which a diploid progenitor germ cell transforms into highly specialized spermatozoa. During spermatogenesis, membrane remodeling takes place, and cell membrane permeability and liquidity undergo phase-specific changes, which are all associated with the alteration of membrane lipids. Lipids are important components of the germ cell membrane, whose volume and ratio fluctuate in different phases of spermatogenesis. Abnormal lipid metabolism can cause spermatogenic dysfunction and consequently male infertility. Germ cell membrane lipids are mainly composed of cholesterol, phospholipids and glycolipids, which play critical roles in cell adhesion and signal transduction during spermatogenesis. An insight into the correlation of membrane lipids with spermatogenesis helps us to better understand the mechanisms of spermatogenesis and provide new approaches to the diagnosis and treatment of male infertility.

Some Pitfalls in Special Relativity

Science.gov (United States)

Chai, An-Ti

1973-01-01

The problem of observing a collision between two spaceships is utilized to illustrate the misuse of time dilation and length contraction, and the incorrect description of space-time coordinates in special relativity. (Author/DF)

Planning, Coordinating, and Managing Off-Site Storage is an Area of Increasing, Professional Responsibility for Special Collections Departments

Directory of Open Access Journals (Sweden)

Melissa Goertzen

2016-03-01

two locations instead of one. Also, the integration of new workflows required additional oversight to ensure adequate control at all points of process. Static staffing levels and increased levels of responsibility impacted preservation and conservation activities as well. A central concern was the handling of materials by facility staff not trained as special collections professionals. In regard to the facilities themselves, a general concern was that commercial warehouses do not always provide the kind of environmental control systems recommended for storage of special collections materials. Of the total sample group, 12 participants (19% said their institution does not use off-site storage for special collections. When asked if this may occur in the future, four directors (33% said they anticipate off-site storage use within the next five years. Lack of space was listed as the primary motivation. Conclusion – Study findings provide evidence for what was previously known anecdotally: planning, coordinating, and managing off-site storage is a significant professional responsibility that will only grow in the future. As primary resources are integrated into research, teaching, and learning activities, the acquisition of special collections materials will continue to grow. Discussions regarding off-site storage workflows and strategic planning will continue as professionals seek compromises that meet the unique needs of acquisition, preservation, and public service.

Morphology, development, and evolution of fetal membranes and placentation in squamate reptiles.

Science.gov (United States)

Blackburn, Daniel G; Flemming, Alexander F

2009-09-15

Current studies on fetal membranes of reptiles are providing insight into three major historical transformations: evolution of the amniote egg, evolution of viviparity, and evolution of placentotrophy. Squamates (lizards and snakes) are ideal for such studies because their fetal membranes sustain embryos in oviparous species and contribute to placentas in viviparous species. Ultrastructure of the fetal membranes in oviparous corn snakes (Pituophis guttatus) shows that the chorioallantois is specialized for gas exchange and the omphalopleure, for water absorption. Transmission and scanning electron microscopic studies of viviparous thamnophine snakes (Thamnophis, Storeria) have revealed morphological specializations for gas exchange and absorption in the intra-uterine environment that represent modifications of features found in oviparous species. Thus, fetal membranes in oviparous species show morphological differentiation for distinct functions that have been recruited and enhanced under viviparous conditions. The ultimate in specialization of fetal membranes is found in viviparous skinks of South America (Mabuya) and Africa (Trachylepis, Eumecia), in which placentotrophy accounts for nearly all of the nutrients for development. Ongoing research on these lizards has revealed morphological specializations of the chorioallantoic placenta through which nutrient transfer is accomplished. In addition, African Trachylepis show an invasive form of implantation, in which uterine epithelium is replaced by invading chorionic cells. Ongoing analysis of these lizards shows how integration of multiple lines of evidence can provide insight into the evolution of developmental and reproductive specializations once thought to be confined to eutherian mammals.

Special theory on chemical engineering

International Nuclear Information System (INIS)

1987-06-01

This book give a special description about chemical engineering. The contents of this book are special technique for isolation on introduction and separation by membrane, biochemistry engineering, process system engineering, energy engineering, environment engineering, a high molecular new material, election material and research on surface property of catalyst. It has appendixes on history of transition on Korean chemical engineering text contents and history of the activity of Korea chemical engineering institute.

Fabrication of bioinspired composite nanofiber membranes with robust superhydrophobicity for direct contact membrane distillation.

Science.gov (United States)

Liao, Yuan; Wang, Rong; Fane, Anthony G

2014-06-03

The practical application of membrane distillation (MD) for water purification is hindered by the absence of desirable membranes that can fulfill the special requirements of the MD process. Compared to the membranes fabricated by other methods, nanofiber membranes produced by electrospinning are of great interest due to their high porosity, low tortuosity, large surface pore size, and high surface hydrophobicity. However, the stable performance of the nanofiber membranes in the MD process is still unsatisfactory. Inspired by the unique structure of the lotus leaf, this study aimed to develop a strategy to construct superhydrophobic composite nanofiber membranes with robust superhydrophobicity and high porosity suitable for use in MD. The newly developed membrane consists of a superhydrophobic silica-PVDF composite selective skin formed on a polyvinylidene fluoride (PVDF) porous nanofiber scaffold via electrospinning. This fabrication method could be easily scaled up due to its simple preparation procedures. The effects of silica diameter and concentration on membrane contact angle, sliding angle, and MD performance were investigated thoroughly. For the first time, the direct contact membrane distillation (DCMD) tests demonstrate that the newly developed membranes are able to present stable high performance over 50 h of testing time, and the superhydrophobic selective layer exhibits excellent durability in ultrasonic treatment and a continuous DCMD test. It is believed that this novel design strategy has great potential for MD membrane fabrication.

The generator coordinate method in nuclear physics

International Nuclear Information System (INIS)

Giraud, B.G.

1981-01-01

The generator coordinate method is introduced as a physical description of a N-body system in a subspace of a reduced number of degrees of freedom. Special attention is placed on the identification of these special, 'collective' degrees of freedom. It is shown in particular that the method has close links with the Born-Oppenheimer approximation and also that considerations of differential geometry are useful in the theory. A set of applications is discussed and in particular the case of nuclear collisions is considered. (Author) [pt

Membrane rafts: a potential gateway for bacterial entry into host cells.

Science.gov (United States)

Hartlova, Anetta; Cerveny, Lukas; Hubalek, Martin; Krocova, Zuzana; Stulik, Jiri

2010-04-01

Pathogenic bacteria have developed various mechanisms to evade host immune defense systems. Invasion of pathogenic bacteria requires interaction of the pathogen with host receptors, followed by activation of signal transduction pathways and rearrangement of the cytoskeleton to facilitate bacterial entry. Numerous bacteria exploit specialized plasma membrane microdomains, commonly called membrane rafts, which are rich in cholesterol, sphingolipids and a special set of signaling molecules which allow entry to host cells and establishment of a protected niche within the host. This review focuses on the current understanding of the raft hypothesis and the means by which pathogenic bacteria subvert membrane microdomains to promote infection.

Sensing voltage across lipid membranes

Science.gov (United States)

Swartz, Kenton J.

2009-01-01

The detection of electrical potentials across lipid bilayers by specialized membrane proteins is required for many fundamental cellular processes such as the generation and propagation of nerve impulses. These membrane proteins possess modular voltage-sensing domains, a notable example being the S1-S4 domains of voltage-activated ion channels. Ground-breaking structural studies on these domains explain how voltage sensors are designed and reveal important interactions with the surrounding lipid membrane. Although further structures are needed to fully understand the conformational changes that occur during voltage sensing, the available data help to frame several key concepts that are fundamental to the mechanism of voltage sensing. PMID:19092925

The actin homologue MreB organizes the bacterial cell membrane.

Science.gov (United States)

Strahl, Henrik; Bürmann, Frank; Hamoen, Leendert W

2014-03-07

The eukaryotic cortical actin cytoskeleton creates specific lipid domains, including lipid rafts, which determine the distribution of many membrane proteins. Here we show that the bacterial actin homologue MreB displays a comparable activity. MreB forms membrane-associated filaments that coordinate bacterial cell wall synthesis. We noticed that the MreB cytoskeleton influences fluorescent staining of the cytoplasmic membrane. Detailed analyses combining an array of mutants, using specific lipid staining techniques and spectroscopic methods, revealed that MreB filaments create specific membrane regions with increased fluidity (RIFs). Interference with these fluid lipid domains (RIFs) perturbs overall lipid homeostasis and affects membrane protein localization. The influence of MreB on membrane organization and fluidity may explain why the active movement of MreB stimulates membrane protein diffusion. These novel MreB activities add additional complexity to bacterial cell membrane organization and have implications for many membrane-associated processes.

32 CFR 989.34 - Special and emergency procedures.

Science.gov (United States)

2010-07-01

... PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.34 Special and emergency procedures. (a... regulations or this part. If possible, promptly notify HQ USAF/A7CI, for SAF/IEE coordination and CEQ.... Coordination in this instance must take place as soon as practicable. [64 FR 38129, July 15, 1999, as amended...

Novel thermal efficiency-based model for determination of thermal conductivity of membrane distillation membranes

International Nuclear Information System (INIS)

Vanneste, Johan; Bush, John A.; Hickenbottom, Kerri L.; Marks, Christopher A.; Jassby, David

2017-01-01

Development and selection of membranes for membrane distillation (MD) could be accelerated if all performance-determining characteristics of the membrane could be obtained during MD operation without the need to recur to specialized or cumbersome porosity or thermal conductivity measurement techniques. By redefining the thermal efficiency, the Schofield method could be adapted to describe the flux without prior knowledge of membrane porosity, thickness, or thermal conductivity. A total of 17 commercially available membranes were analyzed in terms of flux and thermal efficiency to assess their suitability for application in MD. The thermal-efficiency based model described the flux with an average %RMSE of 4.5%, which was in the same range as the standard deviation on the measured flux. The redefinition of the thermal efficiency also enabled MD to be used as a novel thermal conductivity measurement device for thin porous hydrophobic films that cannot be measured with the conventional laser flash diffusivity technique.

PAIR MOTOR COORDINATION ACTION IN SPORTSMEN (ON THE EXAMPLE OF BALLROOM DANCING

Directory of Open Access Journals (Sweden)

L. V. Kapilevich

2013-01-01

Full Text Available Learn a special coordinating pair of motor actions in athletes engaged sport ballroom dancing, depending on gender and sportsmanship. The results suggest that beginners dominated coordination, performed individually, while the highly skilled dancers better developed coordination, carried out in pairs. Athletes average individual coordination disturbed by the emergence of sex differences build movements and coordination pair is not formed. The asymmetry of the coordination abilities manifested in the predominance of the deviation from equilibrium (to the right of men and to the left – in women. In this case, the athletes of low and medium level of skill to maintain the leading element of balance and coordination is the visual analyzer, while the skilled dancers defining role goes to the vestibular apparatus.

Fabrication of Polybenzimidazole/Palladium Nanoparticles Hollow Fiber Membranes for Hydrogen Purification

KAUST Repository

Villalobos, Luis Francisco

2017-09-13

A novel scheme to fabricate polybenzimidazole (PBI) hollow fiber membranes with a thin skin loaded with fully dispersed palladium nanoparticles is proposed for the first time. Palladium is added to the membrane during the spinning process in the form of ions that coordinate to the imidazole groups of the polymer. This is attractive for membrane production because agglomeration of nanoparticles is minimized and the high-cost metal is incorporated in only the selective layer—where it is required. Pd-containing membranes achieve three orders of magnitude higher H2 permeances and a twofold improvement in H2/CO2 selectivity compared to pure PBI hollow fiber membranes.

Sandwich-structured hollow fiber membranes for osmotic power generation

KAUST Repository

Fu, Feng Jiang; Zhang, Sui; Chung, Neal Tai-Shung

2015-01-01

In this work, a novel sandwich-structured hollow fiber membrane has been developed via a specially designed spinneret and optimized spinning conditions. With this specially designed spinneret, the outer layer, which is the most crucial part of the sandwich-structured membrane, is maintained the same as the traditional dual-layer membrane. The inner substrate layer is separated into two layers: (1) an ultra-thin middle layer comprising a high molecular weight polyvinylpyrrolidone (PVP) additive to enhance integration with the outer polybenzimidazole (PBI) selective layer, and (2) an inner-layer to provide strong mechanical strength for the membrane. Experimental results show that a high water permeability and good mechanical strength could be achieved without the expensive post treatment process to remove PVP which was necessary for the dual-layer pressure retarded osmosis (PRO) membranes. By optimizing the composition, the membrane shows a maximum power density of 6.23W/m2 at a hydraulic pressure of 22.0bar when 1M NaCl and 10mM NaCl are used as the draw and feed solutions, respectively. To our best knowledge, this is the best phase inversion hollow fiber membrane with an outer selective PBI layer for osmotic power generation. In addition, this is the first work that shows how to fabricate sandwich-structured hollow fiber membranes for various applications. © 2015 Elsevier B.V.

Sandwich-structured hollow fiber membranes for osmotic power generation

KAUST Repository

Fu, Feng Jiang

2015-11-01

In this work, a novel sandwich-structured hollow fiber membrane has been developed via a specially designed spinneret and optimized spinning conditions. With this specially designed spinneret, the outer layer, which is the most crucial part of the sandwich-structured membrane, is maintained the same as the traditional dual-layer membrane. The inner substrate layer is separated into two layers: (1) an ultra-thin middle layer comprising a high molecular weight polyvinylpyrrolidone (PVP) additive to enhance integration with the outer polybenzimidazole (PBI) selective layer, and (2) an inner-layer to provide strong mechanical strength for the membrane. Experimental results show that a high water permeability and good mechanical strength could be achieved without the expensive post treatment process to remove PVP which was necessary for the dual-layer pressure retarded osmosis (PRO) membranes. By optimizing the composition, the membrane shows a maximum power density of 6.23W/m2 at a hydraulic pressure of 22.0bar when 1M NaCl and 10mM NaCl are used as the draw and feed solutions, respectively. To our best knowledge, this is the best phase inversion hollow fiber membrane with an outer selective PBI layer for osmotic power generation. In addition, this is the first work that shows how to fabricate sandwich-structured hollow fiber membranes for various applications. © 2015 Elsevier B.V.

Integrating complex functions: coordination of nuclear pore complex assembly and membrane expansion of the nuclear envelope requires a family of integral membrane proteins.

Science.gov (United States)

Schneiter, Roger; Cole, Charles N

2010-01-01

The nuclear envelope harbors numerous large proteinaceous channels, the nuclear pore complexes (NPCs), through which macromolecular exchange between the cytosol and the nucleoplasm occurs. This double-membrane nuclear envelope is continuous with the endoplasmic reticulum and thus functionally connected to such diverse processes as vesicular transport, protein maturation and lipid synthesis. Recent results obtained from studies in Saccharomyces cerevisiae indicate that assembly of the nuclear pore complex is functionally dependent upon maintenance of lipid homeostasis of the ER membrane. Previous work from one of our laboratories has revealed that an integral membrane protein Apq12 is important for the assembly of functional nuclear pores. Cells lacking APQ12 are viable but cannot grow at low temperatures, have aberrant NPCs and a defect in mRNA export. Remarkably, these defects in NPC assembly can be overcome by supplementing cells with a membrane fluidizing agent, benzyl alcohol, suggesting that Apq12 impacts the flexibility of the nuclear membrane, possibly by adjusting its lipid composition when cells are shifted to a reduced temperature. Our new study now expands these findings and reveals that an essential membrane protein, Brr6, shares at least partially overlapping functions with Apq12 and is also required for assembly of functional NPCs. A third nuclear envelope membrane protein, Brl1, is related to Brr6, and is also required for NPC assembly. Because maintenance of membrane homeostasis is essential for cellular survival, the fact that these three proteins are conserved in fungi that undergo closed mitoses, but are not found in metazoans or plants, may indicate that their functions are performed by proteins unrelated at the primary sequence level to Brr6, Brl1 and Apq12 in cells that disassemble their nuclear envelopes during mitosis.

The status of physical training judoists of 14–16 years on indicators coordinating abilities

Directory of Open Access Journals (Sweden)

Chumak Yuliia

2014-08-01

Full Text Available Purpose: to determine the impact of the special physical training aimed at developing coordination skills. Material and Methods: in 57 explored participated judo 14-16 years old male, who trained at the stage of the specially-basic training. Methods: Analysis of scientific and technical literature, testing physical properties, methods of mathematical statistics. Results: actual problems of physical training judo. the level of physical fitness for the performance of coordination abilities. Analyzed the typical training program for judo and determined its effectiveness. Conclusions: found that physical training judo 14–16 years on indicators of quality of coordination within the average. Therefore, to achieve good results in the need to improve the modern sport judo training program. Formed guidelines for building a training process designed to develop coordination skills.

Non-Native Metal Ion Reveals the Role of Electrostatics in Synaptotagmin 1-Membrane Interactions.

Science.gov (United States)

Katti, Sachin; Nyenhuis, Sarah B; Her, Bin; Srivastava, Atul K; Taylor, Alexander B; Hart, P John; Cafiso, David S; Igumenova, Tatyana I

2017-06-27

C2 domains are independently folded modules that often target their host proteins to anionic membranes in a Ca 2+ -dependent manner. In these cases, membrane association is triggered by Ca 2+ binding to the negatively charged loop region of the C2 domain. Here, we used a non-native metal ion, Cd 2+ , in lieu of Ca 2+ to gain insight into the contributions made by long-range Coulombic interactions and direct metal ion-lipid bridging to membrane binding. Using X-ray crystallography, NMR, Förster resonance energy transfer, and vesicle cosedimentation assays, we demonstrate that, although Cd 2+ binds to the loop region of C2A/B domains of synaptotagmin 1 with high affinity, long-range Coulombic interactions are too weak to support membrane binding of individual domains. We attribute this behavior to two factors: the stoichiometry of Cd 2+ binding to the loop regions of the C2A and C2B domains and the impaired ability of Cd 2+ to directly coordinate the lipids. In contrast, electron paramagnetic resonance experiments revealed that Cd 2+ does support membrane binding of the C2 domains in full-length synaptotagmin 1, where the high local lipid concentrations that result from membrane tethering can partially compensate for lack of a full complement of divalent metal ions and specific lipid coordination in Cd 2+ -complexed C2A/B domains. Our data suggest that long-range Coulombic interactions alone can drive the initial association of C2A/B with anionic membranes and that Ca 2+ further augments membrane binding by the formation of metal ion-lipid coordination bonds and additional Ca 2+ ion binding to the C2 domain loop regions.

Internal or shape coordinates in the n-body problem

International Nuclear Information System (INIS)

Littlejohn, R.G.; Reinsch, M.

1995-01-01

The construction of global shape coordinates for the n-body problem is considered. Special attention is given to the three- and four-body problems. Quantities, including candidates for coordinates, are organized according to their transformation properties under so-called democracy transformations (orthogonal transformations of Jacobi vectors). Important submanifolds of shape space are identified and their topology studied, including the manifolds upon which shapes are coplanar or collinear, and the manifolds upon which the moment of inertia tensor is degenerate

Bioelectrochemistry II membrane phenomena

CERN Document Server

Blank, M

1987-01-01

This book contains the lectures of the second course devoted to bioelectro­ chemistry, held within the framework of the International School of Biophysics. In this course another very large field of bioelectrochemistry, i. e. the field of Membrane Phenomena, was considered, which itself consists of several different, but yet related subfields. Here again, it can be easily stated that it is impossible to give a complete and detailed picture of all membrane phenomena of biological interest in a short course of about one and half week. Therefore the same philosophy, as the one of the first course, was followed, to select a series of lectures at postgraduate level, giving a synthesis of several membrane phenomena chosen among the most'important ones. These lectures should show the large variety of membrane-regulated events occurring in living bodies, and serve as sound interdisciplinary basis to start a special­ ized study of biological phenomena, for which the investigation using the dual approach, physico-che...

Facilitating Group Decision-Making: Facilitator's Subjective Theories on Group Coordination

Directory of Open Access Journals (Sweden)

Michaela Kolbe

2008-10-01

Full Text Available A key feature of group facilitation is motivating and coordinating people to perform their joint work. This paper focuses on group coordination which is a prerequisite to group effectiveness, especially in complex tasks. Decision-making in groups is a complex task that consequently needs to be coordinated by explicit rather than implicit coordination mechanisms. Based on the embedded definition that explicit coordination does not just happen but is purposely executed by individuals, we argue that individual coordination intentions and mechanisms should be taken into account. Thus far, the subjective perspective of coordination has been neglected in coordination theory, which is understandable given the difficulties in defining and measuring subjective aspects of group facilitation. We therefore conducted focused interviews with eight experts who either worked as senior managers or as experienced group facilitators and analysed their approaches to group coordination using methods of content analysis. Results show that these experts possess sophisticated mental representations of their coordination behaviour. These subjective coordination theories can be organised in terms of coordination schemes in which coordination-releasing situations are facilitated by special coordination mechanisms that, in turn, lead to the perception of specific consequences. We discuss the importance of these subjective coordination theories for effectively facilitating group decision-making and minimising process losses. URN: urn:nbn:de:0114-fqs0901287

Ion transport Modeling in a Bipolar Membrane

International Nuclear Information System (INIS)

Kim, Jung Soo; Park, Kwang Heon; Kim, Kwang Wook

2010-01-01

The COL(Carbonate-based Oxidative Leaching) process is an environmentally-friendly technique for collecting only uranium from spent fuel with oxidation leaching/ precipitation of carbonate solution. The bipolar membrane used for the electrolyte circulation of the salt used in the COL process is a special form of ion exchange membrane which combines CEM(cation exchange membrane) and AEM(anion exchange membrane). After arranging positive ion exchange layer toward negative terminal and positive ion exchange layer toward positive terminal, then supply electricity, water molecules are decomposed into protons and hydroxyl ions by a strong electric field in the transition region inside bipolar membrane.1) In this study, a theoretical approach to increase the efficiency of Na + and NO3 - ion collecting device using bipolar membrane was taken and simulating using the COMSOL program was tried. The details of results are also discussed

Mechanical signaling coordinates the embryonic heartbeat

Science.gov (United States)

Chiou, Kevin K.; Rocks, Jason W.; Chen, Christina Yingxian; Cho, Sangkyun; Merkus, Koen E.; Rajaratnam, Anjali; Robison, Patrick; Tewari, Manorama; Vogel, Kenneth; Majkut, Stephanie F.; Prosser, Benjamin L.; Discher, Dennis E.; Liu, Andrea J.

2016-01-01

In the beating heart, cardiac myocytes (CMs) contract in a coordinated fashion, generating contractile wave fronts that propagate through the heart with each beat. Coordinating this wave front requires fast and robust signaling mechanisms between CMs. The primary signaling mechanism has long been identified as electrical: gap junctions conduct ions between CMs, triggering membrane depolarization, intracellular calcium release, and actomyosin contraction. In contrast, we propose here that, in the early embryonic heart tube, the signaling mechanism coordinating beats is mechanical rather than electrical. We present a simple biophysical model in which CMs are mechanically excitable inclusions embedded within the extracellular matrix (ECM), modeled as an elastic-fluid biphasic material. Our model predicts strong stiffness dependence in both the heartbeat velocity and strain in isolated hearts, as well as the strain for a hydrogel-cultured CM, in quantitative agreement with recent experiments. We challenge our model with experiments disrupting electrical conduction by perfusing intact adult and embryonic hearts with a gap junction blocker, β-glycyrrhetinic acid (BGA). We find this treatment causes rapid failure in adult hearts but not embryonic hearts—consistent with our hypothesis. Last, our model predicts a minimum matrix stiffness necessary to propagate a mechanically coordinated wave front. The predicted value is in accord with our stiffness measurements at the onset of beating, suggesting that mechanical signaling may initiate the very first heartbeats. PMID:27457951

Radiation induced graft copolymerization for preparation of cation exchange membranes: a review

International Nuclear Information System (INIS)

Mohamed Mahmoud Nasef; Hamdani Saidi; Hussin Mohd Nor

1999-01-01

Cation exchange membranes are regarded as the ideal solid polymer electrolyte materials for the development of various electrochemical energy conversion applications where significant improvements in the current density are required. Such membranes require special polymers and preparation techniques to maintain high chemical , mechanical and thermal stability in addition to high ionic conductivity and low resistance. A lot of different techniques have been proposed in the past to prepare such membranes. Radiation-induced graft copolymerization provides an attractive ft method for modification of chemical and physical properties of polymeric materials and is of particular interest in achieving specially desired cation exchange membranes as well as excellent membrane properties. This is due to the ability to control the membrane compositions as well as properties by proper selection of grafting conditions. Therefore numerous parameters have to be investigated to properly select the right polymeric materials, radiation grafting technique and the grafting conditions to be employed. In this paper a state-of-the-art of radiation-induced graft copolymerization for preparation of cation exchange membranes and their applications are briefly reviewed. (Author)

Evaluation of freshmen coordination abilities on practical training in gymnastics

Directory of Open Access Journals (Sweden)

I.A. Tereschenko

2013-06-01

Full Text Available Measured coordination abilities (baseline to the static and dynamic equilibrium of the body, the space-time orientation on the support and in unsupported position, proprioception sense, vestibular stability, vestibular sensitivity, coordination limbs symmetrical and asymmetrical. Coordination abilities were also measured under difficult conditions. The study involved 238 students aged 17 - 18 years. Registered a positive trend of improving performance motor tests, development of educational material. Students who specialize in difficult to coordinate sports had significantly better performance. Found that the content of the material work programs of sports and educational disciplines helps improve sensorimotor coordination tasks students. It is noted that the content of the training material is the basis for efficient formation of motor skills and motor skills development of gymnastic exercises. Recommended ways to increase sports and technical and professional skills of students.

Synthesis Polysulfone-Acetylethanol Ultrafiltration Membranes. Application to Oily Wastewater Treatment

OpenAIRE

Masuelli, Martin Alberto

2016-01-01

Chemical functionalization of polymers after the synthesis of membranes has great importance for various applications separative processes of industrial or environmental interest. Polysulfone (PSf) is one of the most applied polymers for separative processes used especially in membrane technology, due to its excellent chemical, mechanical and thermal properties. The functionalization of PSf makes it very attractive to give special characteristics due to their high hydrophobicity and membrane ...

Physics of biological membranes

Science.gov (United States)

Mouritsen, Ole G.

The biological membrane is a complex system consisting of an aqueous biomolecular planar aggregate of predominantly lipid and protein molecules. At physiological temperatures, the membrane may be considered a thin (˜50Å) slab of anisotropic fluid characterized by a high lateral mobility of the various molecular components. A substantial fraction of biological activity takes place in association with membranes. As a very lively piece of condensed matter, the biological membrane is a challenging research topic for both the experimental and theoretical physicists who are facing a number of fundamental physical problems including molecular self-organization, macromolecular structure and dynamics, inter-macromolecular interactions, structure-function relationships, transport of energy and matter, and interfacial forces. This paper will present a brief review of recent theoretical and experimental progress on such problems, with special emphasis on lipid bilayer structure and dynamics, lipid phase transitions, lipid-protein and lipid-cholesterol interactions, intermembrane forces, and the physical constraints imposed on biomembrane function and evolution. The paper advocates the dual point of view that there are a number of interesting physics problems in membranology and, at the same time, that the physical properties of biomembranes are important regulators of membrane function.

76 FR 13371 - Office of Special Education and Rehabilitative Services; Overview Information; Personnel...

Science.gov (United States)

2011-03-11

... DEPARTMENT OF EDUCATION Office of Special Education and Rehabilitative Services; Overview... personnel--in special education, related services, early intervention, and regular education--to work with... early intervention, special education, or related services. In a 2004 survey of coordinators for the...

Spatio-temporal Remodeling of Functional Membrane Microdomains Organizes the Signaling Networks of a Bacterium

NARCIS (Netherlands)

Schneider, Johannes; Klein, Teresa; Mielich-Süss, Benjamin; Koch, Gudrun; Franke, Christian; Kuipers, Oscar P; Kovács, Ákos T; Sauer, Markus; Lopez, Daniel

Lipid rafts are membrane microdomains specialized in the regulation of numerous cellular processes related to membrane organization, as diverse as signal transduction, protein sorting, membrane trafficking or pathogen invasion. It has been proposed that this functional diversity would require a

Proteolytic Enzymes Clustered in Specialized Plasma-Membrane Domains Drive Endothelial Cells' Migration.

Directory of Open Access Journals (Sweden)

Monica Salamone

Full Text Available In vitro cultured endothelial cells forming a continuous monolayer establish stable cell-cell contacts and acquire a "resting" phenotype; on the other hand, when growing in sparse conditions these cells acquire a migratory phenotype and invade the empty area of the culture. Culturing cells in different conditions, we compared expression and clustering of proteolytic enzymes in cells having migratory versus stationary behavior. In order to observe resting and migrating cells in the same microscopic field, a continuous cell monolayer was wounded. Increased expression of proteolytic enzymes was evident in cell membranes of migrating cells especially at sprouting sites and in shed membrane vesicles. Gelatin zymography and western blotting analyses confirmed that in migrating cells, expression of membrane-bound and of vesicle-associated proteolytic enzymes are increased. The enzymes concerned include MMP-2, MMP-9, MT1-MMP, seprase, DPP4 (DiPeptidyl Peptidase 4 and uPA. Shed membrane vesicles were shown to exert degradative activity on ECM components and produce substrates facilitating cell migration. Vesicles shed by migrating cells degraded ECM components at an increased rate; as a result their effect on cell migration was amplified. Inhibiting either Matrix Metallo Proteases (MMPs or Serine Integral Membrane Peptidases (SIMPs caused a decrease in the stimulatory effect of vesicles, inhibiting the spontaneous migratory activity of cells; a similar result was also obtained when a monoclonal antibody acting on DPP4 was tested. We conclude that proteolytic enzymes have a synergistic stimulatory effect on cell migration and that their clustering probably facilitates the proteolytic activation cascades needed to produce maximal degradative activity on cell substrates during the angiogenic process.

Proteolytic Enzymes Clustered in Specialized Plasma-Membrane Domains Drive Endothelial Cells' Migration.

Science.gov (United States)

Salamone, Monica; Carfì Pavia, Francesco; Ghersi, Giulio

2016-01-01

In vitro cultured endothelial cells forming a continuous monolayer establish stable cell-cell contacts and acquire a "resting" phenotype; on the other hand, when growing in sparse conditions these cells acquire a migratory phenotype and invade the empty area of the culture. Culturing cells in different conditions, we compared expression and clustering of proteolytic enzymes in cells having migratory versus stationary behavior. In order to observe resting and migrating cells in the same microscopic field, a continuous cell monolayer was wounded. Increased expression of proteolytic enzymes was evident in cell membranes of migrating cells especially at sprouting sites and in shed membrane vesicles. Gelatin zymography and western blotting analyses confirmed that in migrating cells, expression of membrane-bound and of vesicle-associated proteolytic enzymes are increased. The enzymes concerned include MMP-2, MMP-9, MT1-MMP, seprase, DPP4 (DiPeptidyl Peptidase 4) and uPA. Shed membrane vesicles were shown to exert degradative activity on ECM components and produce substrates facilitating cell migration. Vesicles shed by migrating cells degraded ECM components at an increased rate; as a result their effect on cell migration was amplified. Inhibiting either Matrix Metallo Proteases (MMPs) or Serine Integral Membrane Peptidases (SIMPs) caused a decrease in the stimulatory effect of vesicles, inhibiting the spontaneous migratory activity of cells; a similar result was also obtained when a monoclonal antibody acting on DPP4 was tested. We conclude that proteolytic enzymes have a synergistic stimulatory effect on cell migration and that their clustering probably facilitates the proteolytic activation cascades needed to produce maximal degradative activity on cell substrates during the angiogenic process.

Proteolytic Enzymes Clustered in Specialized Plasma-Membrane Domains Drive Endothelial Cells’ Migration

Science.gov (United States)

Salamone, Monica; Carfì Pavia, Francesco

2016-01-01

In vitro cultured endothelial cells forming a continuous monolayer establish stable cell-cell contacts and acquire a “resting” phenotype; on the other hand, when growing in sparse conditions these cells acquire a migratory phenotype and invade the empty area of the culture. Culturing cells in different conditions, we compared expression and clustering of proteolytic enzymes in cells having migratory versus stationary behavior. In order to observe resting and migrating cells in the same microscopic field, a continuous cell monolayer was wounded. Increased expression of proteolytic enzymes was evident in cell membranes of migrating cells especially at sprouting sites and in shed membrane vesicles. Gelatin zymography and western blotting analyses confirmed that in migrating cells, expression of membrane-bound and of vesicle-associated proteolytic enzymes are increased. The enzymes concerned include MMP-2, MMP-9, MT1-MMP, seprase, DPP4 (DiPeptidyl Peptidase 4) and uPA. Shed membrane vesicles were shown to exert degradative activity on ECM components and produce substrates facilitating cell migration. Vesicles shed by migrating cells degraded ECM components at an increased rate; as a result their effect on cell migration was amplified. Inhibiting either Matrix Metallo Proteases (MMPs) or Serine Integral Membrane Peptidases (SIMPs) caused a decrease in the stimulatory effect of vesicles, inhibiting the spontaneous migratory activity of cells; a similar result was also obtained when a monoclonal antibody acting on DPP4 was tested. We conclude that proteolytic enzymes have a synergistic stimulatory effect on cell migration and that their clustering probably facilitates the proteolytic activation cascades needed to produce maximal degradative activity on cell substrates during the angiogenic process. PMID:27152413

Transparency and Coordinated Effects in European Merger Control

DEFF Research Database (Denmark)

Albæk, Svend; Møllgaard, H. Peter; Overgaard, Per Baltzer

2010-01-01

In this paper, we first outline the foundations in economic theory of so-called coordinated effects with a particular view to mergers and with a special focus on transparency. Then, we review a number of seminal merger cases in EU competition policy (Airtours, Sony/BMG, ABF/GBI Business) in light...

Tetraspanin-enriched microdomains: a functional unit in cell plasma membranes.

Science.gov (United States)

Yáñez-Mó, María; Barreiro, Olga; Gordon-Alonso, Mónica; Sala-Valdés, Mónica; Sánchez-Madrid, Francisco

2009-09-01

Membrane lipids and proteins are non-randomly distributed and are unable to diffuse freely in the plane of the membrane. This is because of multiple constraints imposed both by the cortical cytoskeleton and by the preference of lipids and proteins to cluster into diverse and specialized membrane domains, including tetraspanin-enriched microdomains, glycosylphosphatidyl inositol-linked proteins nanodomains and caveolae, among others. Recent biophysical characterization of tetraspanin-enriched microdomains suggests that they might be specially suited for the regulation of avidity of adhesion receptors and the compartmentalization of enzymatic activities. Moreover, modulation by tetraspanins of the function of adhesion receptors involved in inflammation, lymphocyte activation, cancer and pathogen infection suggests potential as therapeutic targets. This review explores this emerging picture of tetraspanin microdomains and discusses the implications for cell adhesion, proteolysis and pathogenesis.

Scaling Up Coordinate Descent Algorithms for Large ℓ1 Regularization Problems

Energy Technology Data Exchange (ETDEWEB)

Scherrer, Chad; Halappanavar, Mahantesh; Tewari, Ambuj; Haglin, David J.

2012-07-03

We present a generic framework for parallel coordinate descent (CD) algorithms that has as special cases the original sequential algorithms of Cyclic CD and Stochastic CD, as well as the recent parallel Shotgun algorithm of Bradley et al. We introduce two novel parallel algorithms that are also special cases---Thread-Greedy CD and Coloring-Based CD---and give performance measurements for an OpenMP implementation of these.

Selective separation of oil and water with special wettability mesh membranes

KAUST Repository

Liu, Defei; Yu, Yuanlie; Chen, Xin; Zheng, Yuying

2017-01-01

that these superhydrophobic/superoleophilic or oleophobic/superhydrophilic mesh membranes are durable, stable and reusable, making them encouraging candidates for practical oil-polluted water treatment.

A comprehensive special educational diagnostic assessment of five-year-old children with developmental coordination disorder (case studies

Directory of Open Access Journals (Sweden)

Tjasa Filipcic

2016-07-01

Full Text Available Developmental coordination disorder (DCD is a neurodevelopmental disorder which affects different areas of an individual's everyday living and learning. Children with DCD are often diagnosed late, at school age, when difficulties with writing, organization and executive functions arise, even though one could have seen signs of probable DCD very early in childhood. The aim of this study was to further assess five-year-old, preschool children recognized as children with DCD, and develop a model for a comprehensive special educational diagnostic assessment of abilities and skills in five-year-old children with DCD. The comprehensive diagnostic assessment comprised observations and assessments of children’s everyday skills in their kindergartens. It also included semi-structured interviews with children, their parents and their preschool teachers. Further, children’s skills and abilities in all developmental domains (sensory and motor skills, cognitive abilities, social and emotional development, speech and language development, including emerging literacy skills, and early maths skills were assessed. A qualitative analysis was undertaken to compare individual children’s comprehensive assessments. The developed model included both the strengths and weaknesses of the assessed children.

Deriving force field parameters for coordination complexes

DEFF Research Database (Denmark)

Norrby, Per-Ola; Brandt, Peter

2001-01-01

The process of deriving molecular mechanics force fields for coordination complexes is outlined. Force field basics are introduced with an emphasis on special requirements for metal complexes. The review is then focused on how to set up the initial model, define the target, refine the parameters......, and validate the final force field, Alternatives to force field derivation are discussed briefly....

Transport of Carbon Dioxide through a Biomimetic Membrane

Directory of Open Access Journals (Sweden)

Efstathios Matsaridis

2011-01-01

Full Text Available Biomimetic membranes (BMM based on polymer filters impregnated with lipids or their analogues are widely applied in numerous areas of physics, biology, and medicine. In this paper we report the design and testing of an electrochemical system, which allows the investigation of CO2 transport through natural membranes such as alveoli barrier membrane system and also can be applied for solid-state measurements. The experimental setup comprises a specially designed two-compartment cell with BMM connected with an electrochemical workstation placed in a Faraday cage, two PH meters, and a nondispersive infrared gas analyzer. We prove, experimentally, that the CO2 transport through the natural membranes under different conditions depends on pH and displays a similar behavior as natural membranes. The influence of different drugs on the CO2 transport process through such membranes is discussed.

Coordination in the European Union

OpenAIRE

Martin Feldstein

2013-01-01

This paper examines the sources of current conflict within the EU and the EMU. The topics discussed include the recent ECB policy of bond buying (the OMT policy), the attempts to advance the "European Project" of stronger political union (the fiscal compact, the banking union, and the proposals for budget supervision). Contrary to the claims of the European leadership, the progress that has been made has been by individual countries and not by coordinated action. The special problems of Franc...

Formulating Public Policy in Croatia and the Problem of Policy Coordination

Directory of Open Access Journals (Sweden)

Zdravko Petak

2008-01-01

Full Text Available The paper explores the role of politicians and civil servants in the process of horizontal and vertical policy coordination, with a special emphasis on the specific context of Croatia. Starting from Guy Peters’ typology, which distinguishes four distinct types of coordination, ranging from more simple to more complex ones – negative coordination, positive coordination, policy integration and development of strategies for government, the author stresses that the Croatian case is connected with failure in achieving all types of coordination. One of the reasons for such a situation lies in a low level of applying classical policy analysis in the Croatian public administration system. A direct consequence of this is the existence of the system of coordination based on ad hoc assessment of proposed policies, and not on standard policy analysis tools. Therefore, in the lack of central government policy unit the prominent role in such a system belongs to the finance Minister, who serves as some kind of “policy switchman”.

Special relativity

CERN Document Server

Faraoni, Valerio

2013-01-01

This book offers an essential bridge between college-level introductions and advanced graduate-level books on special relativity. It begins at an elementary level, presenting and discussing the basic concepts normally covered in college-level works, including the Lorentz transformation. Subsequent chapters introduce the four-dimensional worldview implied by the Lorentz transformations, mixing time and space coordinates, before continuing on to the formalism of tensors, a topic usually avoided in lower-level courses. The book’s second half addresses a number of essential points, including the concept of causality; the equivalence between mass and energy, including applications; relativistic optics; and measurements and matter in Minkowski spacetime. The closing chapters focus on the energy-momentum tensor of a continuous distribution of mass-energy and its covariant conservation; angular momentum; a discussion of the scalar field of perfect fluids and the Maxwell field; and general coordinates. Every chapter...

Muscle intermediate filaments and their links to membranes and membranous organelles

International Nuclear Information System (INIS)

Capetanaki, Yassemi; Bloch, Robert J.; Kouloumenta, Asimina; Mavroidis, Manolis; Psarras, Stelios

2007-01-01

Intermediate filaments (IFs) play a key role in the integration of structure and function of striated muscle, primarily by mediating mechanochemical links between the contractile apparatus and mitochondria, myonuclei, the sarcolemma and potentially the vesicle trafficking apparatus. Linkage of all these membranous structures to the contractile apparatus, mainly through the Z-disks, supports the integration and coordination of growth and energy demands of the working myocyte, not only with force transmission, but also with de novo gene expression, energy production and efficient protein and lipid trafficking and targeting. Desmin, the most abundant and intensively studied muscle intermediate filament protein, is linked to proper costamere organization, myoblast and stem cell fusion and differentiation, nuclear shape and positioning, as well as mitochondrial shape, structure, positioning and function. Similar links have been established for lysosomes and lysosome-related organelles, consistent with the presence of widespread links between IFs and membranous structures and the regulation of their fusion, morphology and stabilization necessary for cell survival

Membrane Heterogeneity in Akt Activation in Prostate Cancer

National Research Council Canada - National Science Library

Hager, Martin H

2008-01-01

This project focuses on the novel finding from our group that the serine-threonine kinase Akt1 partitions into specialized membrane microdomains, termed lipid rafts, and that this localization event...

Protein shape and crowding drive domain formation and curvature in biological membranes

NARCIS (Netherlands)

Frese, R.N.; Pamies, Josep C.; Olsen, John D.; Bahatyrova, S.; van der Weij-de Wit, Chantal D.; Aartsma, Thijs J.; Otto, Cornelis; Hunter, C. Neil; Frenkel, Daan; van Grondelle, Rienk

2007-01-01

Folding, curvature, and domain formation are characteristics of many biological membranes. Yet the mechanisms that drive both curvature and the formation of specialized domains enriched in particular protein complexes are unknown. For this reason, studies in membranes whose shape and organization

Experimental substantiation of methodic of 11-13 years old boxers’ coordination development

Directory of Open Access Journals (Sweden)

Yong Qiang Liu

2015-06-01

Full Text Available Purpose: experimental substantiation of methodic of junior boxers’ coordination training. Material: in the research 18 boxers of 11-13 year old age participated. In total, during 4 months 42 trainings were conducted. Total time of coordination load’s fulfillment at each training was 15-45 minutes. Results: dynamic of results in control tests was statistically confident in the tested parameters of movements. It proves effectiveness of usage the tasks with complex-coordination orientation, accented on impact on sensor-informational and motor systems of movements in junior boxers’ trainings. Conclusions: coordination training in boxing at initial stage shall include specialized varied means and methods, which would facilitate formation of motor condition and skills’ basis. Motor condition and skills are a reserve for further rising of coordination abilities’ level of junior sportsmen.

Generalized transformations and coordinates for static spherically symmetric general relativity

Science.gov (United States)

Hill, James M.; O'Leary, Joseph

2018-04-01

We examine a static, spherically symmetric solution of the empty space field equations of general relativity with a non-orthogonal line element which gives rise to an opportunity that does not occur in the standard derivations of the Schwarzschild solution. In these derivations, convenient coordinate transformations and dynamical assumptions inevitably lead to the Schwarzschild solution. By relaxing these conditions, a new solution possibility arises and the resulting formalism embraces the Schwarzschild solution as a special case. The new solution avoids the coordinate singularity associated with the Schwarzschild solution and is achieved by obtaining a more suitable coordinate chart. The solution embodies two arbitrary constants, one of which can be identified as the Newtonian gravitational potential using the weak field limit. The additional arbitrary constant gives rise to a situation that allows for generalizations of the Eddington-Finkelstein transformation and the Kruskal-Szekeres coordinates.

Generalized transformations and coordinates for static spherically symmetric general relativity.

Science.gov (United States)

Hill, James M; O'Leary, Joseph

2018-04-01

We examine a static, spherically symmetric solution of the empty space field equations of general relativity with a non-orthogonal line element which gives rise to an opportunity that does not occur in the standard derivations of the Schwarzschild solution. In these derivations, convenient coordinate transformations and dynamical assumptions inevitably lead to the Schwarzschild solution. By relaxing these conditions, a new solution possibility arises and the resulting formalism embraces the Schwarzschild solution as a special case. The new solution avoids the coordinate singularity associated with the Schwarzschild solution and is achieved by obtaining a more suitable coordinate chart. The solution embodies two arbitrary constants, one of which can be identified as the Newtonian gravitational potential using the weak field limit. The additional arbitrary constant gives rise to a situation that allows for generalizations of the Eddington-Finkelstein transformation and the Kruskal-Szekeres coordinates.

Monitoring coordinate measuring machines by calibrated parts

International Nuclear Information System (INIS)

Weckenmann, A; Lorz, J

2005-01-01

Coordinate measuring machines (CMM) are essential for quality assurance and production control in modern manufacturing. Due to the necessity of assuring traceability during the use of CMM, interim checks with calibrated objects carried out periodically. For this purpose usually special artefacts like standardized ball plates, hole plates, ball bars or step gages are measured. Measuring calibrated series parts would be more advantageous. Applying the substitution method of ISO 15530-3: 2000 such parts can be used. It is less cost intensive and less time consuming than measuring expensive special standardized objects in special programmed measurement routines. Moreover, the measurement results can directly compare with the calibration values; thus, direct information on systematic measurement deviations and uncertainty of the measured features are available. The paper describes a procedure for monitoring horizontal-arm CMMs with calibrated sheet metal series parts

Arabidopsis SNAREs SYP61 and SYP121 coordinate the trafficking of plasma membrane aquaporin PIP2;7 to modulate the cell membrane water permeability.

Science.gov (United States)

Hachez, Charles; Laloux, Timothée; Reinhardt, Hagen; Cavez, Damien; Degand, Hervé; Grefen, Christopher; De Rycke, Riet; Inzé, Dirk; Blatt, Michael R; Russinova, Eugenia; Chaumont, François

2014-07-01

Plant plasma membrane intrinsic proteins (PIPs) are aquaporins that facilitate the passive movement of water and small neutral solutes through biological membranes. Here, we report that post-Golgi trafficking of PIP2;7 in Arabidopsis thaliana involves specific interactions with two syntaxin proteins, namely, the Qc-SNARE SYP61 and the Qa-SNARE SYP121, that the proper delivery of PIP2;7 to the plasma membrane depends on the activity of the two SNAREs, and that the SNAREs colocalize and physically interact. These findings are indicative of an important role for SYP61 and SYP121, possibly forming a SNARE complex. Our data support a model in which direct interactions between specific SNARE proteins and PIP aquaporins modulate their post-Golgi trafficking and thus contribute to the fine-tuning of the water permeability of the plasma membrane. © 2014 American Society of Plant Biologists. All rights reserved.

Non-Brownian diffusion in lipid membranes: Experiments and simulations.

Science.gov (United States)

Metzler, R; Jeon, J-H; Cherstvy, A G

2016-10-01

The dynamics of constituents and the surface response of cellular membranes-also in connection to the binding of various particles and macromolecules to the membrane-are still a matter of controversy in the membrane biophysics community, particularly with respect to crowded membranes of living biological cells. We here put into perspective recent single particle tracking experiments in the plasma membranes of living cells and supercomputing studies of lipid bilayer model membranes with and without protein crowding. Special emphasis is put on the observation of anomalous, non-Brownian diffusion of both lipid molecules and proteins embedded in the lipid bilayer. While single component, pure lipid bilayers in simulations exhibit only transient anomalous diffusion of lipid molecules on nanosecond time scales, the persistence of anomalous diffusion becomes significantly longer ranged on the addition of disorder-through the addition of cholesterol or proteins-and on passing of the membrane lipids to the gel phase. Concurrently, experiments demonstrate the anomalous diffusion of membrane embedded proteins up to macroscopic time scales in the minute time range. Particular emphasis will be put on the physical character of the anomalous diffusion, in particular, the occurrence of ageing observed in the experiments-the effective diffusivity of the measured particles is a decreasing function of time. Moreover, we present results for the time dependent local scaling exponent of the mean squared displacement of the monitored particles. Recent results finding deviations from the commonly assumed Gaussian diffusion patterns in protein crowded membranes are reported. The properties of the displacement autocorrelation function of the lipid molecules are discussed in the light of their appropriate physical anomalous diffusion models, both for non-crowded and crowded membranes. In the last part of this review we address the upcoming field of membrane distortion by elongated membrane

Isolation of Protein Storage Vacuoles and Their Membranes.

Science.gov (United States)

Shimada, Tomoo; Hara-Nishimura, Ikuko

2017-01-01

Protein-storage vacuoles (PSVs) are specialized vacuoles that sequester large amounts of storage proteins. During seed development, PSVs are formed de novo and/or from preexisting lytic vacuoles. Seed PSVs can be subdivided into four distinct compartments: membrane, globoid, matrix, and crystalloid. In this chapter, we introduce easy methods for isolation of PSVs and their membranes from pumpkin seeds. These methods facilitate the identification and characterization of PSV components.

Myosin IIA interacts with the spectrin-actin membrane skeleton to control red blood cell membrane curvature and deformability.

Science.gov (United States)

Smith, Alyson S; Nowak, Roberta B; Zhou, Sitong; Giannetto, Michael; Gokhin, David S; Papoin, Julien; Ghiran, Ionita C; Blanc, Lionel; Wan, Jiandi; Fowler, Velia M

2018-05-08

The biconcave disk shape and deformability of mammalian RBCs rely on the membrane skeleton, a viscoelastic network of short, membrane-associated actin filaments (F-actin) cross-linked by long, flexible spectrin tetramers. Nonmuscle myosin II (NMII) motors exert force on diverse F-actin networks to control cell shapes, but a function for NMII contractility in the 2D spectrin-F-actin network of RBCs has not been tested. Here, we show that RBCs contain membrane skeleton-associated NMIIA puncta, identified as bipolar filaments by superresolution fluorescence microscopy. MgATP disrupts NMIIA association with the membrane skeleton, consistent with NMIIA motor domains binding to membrane skeleton F-actin and contributing to membrane mechanical properties. In addition, the phosphorylation of the RBC NMIIA heavy and light chains in vivo indicates active regulation of NMIIA motor activity and filament assembly, while reduced heavy chain phosphorylation of membrane skeleton-associated NMIIA indicates assembly of stable filaments at the membrane. Treatment of RBCs with blebbistatin, an inhibitor of NMII motor activity, decreases the number of NMIIA filaments associated with the membrane and enhances local, nanoscale membrane oscillations, suggesting decreased membrane tension. Blebbistatin-treated RBCs also exhibit elongated shapes, loss of membrane curvature, and enhanced deformability, indicating a role for NMIIA contractility in promoting membrane stiffness and maintaining RBC biconcave disk cell shape. As structures similar to the RBC membrane skeleton exist in many metazoan cell types, these data demonstrate a general function for NMII in controlling specialized membrane morphology and mechanical properties through contractile interactions with short F-actin in spectrin-F-actin networks.

Poisoning of liquid membrane carriers in extraction of metal ions

International Nuclear Information System (INIS)

Wang, Yuchun; Wang, Dexian

1992-01-01

As means of effective separation and preconcentration, emulsion liquid membranes (ELMs) have found application in many fields including biochemical separation, wastewater treatment, hydrometallurgy, and preconcentration in analytical chemistry. In the extraction of desired metal (scandium, mixed rare earths) ions using chelating extractants (TTA, HDEHP) as liquid membrane carriers, the carriers will become poisoned owing to the presence of even minute quantity of certain high ionic potential ions in the feed solution. The reason for the poisoning of carriers is that those ions have so much greater affinity than the desired ions for the membrane carrier that the ion-carrier coordination compound cannot be stripped at the interior interface of the membrane and gradually no more free carrier transports any metal ions across the membrane. The calculated results are in agreement with the experiments, and methods to avoid the poisoning are given in the paper

Visualization of structural organization of ventral membranes of sheared-open resorbing osteoclasts attached to apatite pellets.

Science.gov (United States)

Akisaka, Toshitaka; Yoshida, Atsushi

2015-05-01

Osteoclasts are highly polarized cells from both morphological and functional points of view. Using quick-freeze, rotary-replication methods combined with cell-shearing, we clarified the variability of cytoplasmic surface of the polarized membranes of osteoclasts seeded on apatite. As to the organization of actin filaments and clathrin sheets, we confirmed almost the same ventral membrane specializations of osteoclasts on apatite as seen on glass plates. The organized actin filaments and membrane-associated particles supported the ruffled border membranes. Inside the actin sealing zone, membrane specializations were not always occupied with the ruffled border but also with other types of membranes. Some osteoclasts formed an actin ring but lacked the ruffled border projections. We report a unique and distinctive membrane modification of apatite-attached osteoclasts, i.e., the presence of dense aggregates of membrane-associated particles and related structures not found in the osteoclasts seeded on glass plates. Actin filament polarity in the podosomes was determined by decoration with myosin S1. The actin filament polarity within podosome appears to be oriented predominantly with its barbed ends toward the core, whereas the interconnecting F-actin appears to be mixed oriented. Two different types of clathrin plaques displayed different distributions: clathrin-dependent endocytosis was observed in the ruffled border regions, whereas flat clathrin sheets were found in the leading edge of lamellipodia and near podosomes. The clathrin sheets adhered to the apatite surface tightly on the ventral membranes overlaying the resorption lacunae. All these membrane specializations as mentioned above may indicate the functional variability of osteoclasts seeded on apatite.

Atomic force microscopy on plasma membranes from Xenopus laevis oocytes containing human aquaporin 4.

OpenAIRE

Orsini, F.; Santacroce, M.; Cremona, A.; Gosvami, N. N.; Lascialfari, A.; Hoogenboom, B. W.

2014-01-01

Atomic force microscopy (AFM) is a unique tool for imaging membrane proteins in near-native environment (embedded in a membrane and in buffer solution) at ~1 nm spatial resolution. It has been most successful on membrane proteins reconstituted in 2D crystals and on some specialized and densely packed native membranes. Here, we report on AFM imaging of purified plasma membranes from Xenopus laevis oocytes, a commonly used system for the heterologous expression of membrane proteins. Isoform M23...

Immobilization of ionophore and surface characterization studies of the titanium(III) ion in a PVC-membrane sensor.

Science.gov (United States)

Rezayi, Majid; Heng, Lee Yook; Kassim, Anuar; Ahmadzadeh, Saeid; Abdollahi, Yadollah; Jahangirian, Hossein

2012-01-01

Novel ionophores comprising various hydroxide and amine structures were immobilized onto poly(vinyl chloride) (PVC) matrices, and these were examined to determine Ti(III) selectivity. To predict the selectivity of Ti(III), a PVC membrane was used to investigate the binding of Ti(III) to c-methylcalix[4]resorcinarene (CMCR). The study showed that the chelating ligand, CMCR, was coordinated selectively to Ti(III) at eight coordination sites involving the oxygen atoms at the interface of the membrane/solution. The membrane was prepared, based on CMCR as an ionophore, sodium tetrakis(4-fluorophenyl) borate (NaTFPB) as a lipophilic ionic additive, and dioctylphthalate (DOP) as a plasticizer. The immobilization of the ionophore and surface characterization studies revealed that the performance of CMCR-immobilized PVC was equivalent to that of mobile ionophores in supported liquid membranes (SLMs). The strengths of the ion-ionophore (CMCR-Ti(OH)(OH(2))(5) (2+)) interactions and the role of ionophores on membranes were studied via UV-Vis, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and and X-ray diffraction (XRD).

Membranes on nanopores for multiplexed single-transporter analyses

International Nuclear Information System (INIS)

Urban, Michael; Tampé, Robert

2016-01-01

The study of membrane proteins as prime drug targets has led to intensified efforts to characterize their structure and function. With regards to the structural analysis of membrane proteins, there have been considerable technological innovations in cryo-EM and X-ray crystallography, but advancements in the elucidation of membrane protein function, especially on a single-molecule level, have been struggling to bridge from basic science to high-throughput applications. There is a need for advanced biosensor platforms allowing membrane protein-mediated transport and potential suppressor libraries to be characterized. Membrane proteins facilitating the translocation of non-electrogenic substrates particularly suffer from a lack of such techniques to date. Here, we summarize recent developments in the field of membrane protein analysis, with a special focus on micro- and nanostructured platforms for purpose of high-throughput screening using fluorescent read-out systems. Additionally, their use as novel biosensor platforms to elucidate non-electrogenic substrate translocation is described. This overview contains 82 references. (author)

Membrane-based technologies for biogas separations.

Science.gov (United States)

Basu, Subhankar; Khan, Asim L; Cano-Odena, Angels; Liu, Chunqing; Vankelecom, Ivo F J

2010-02-01

Over the past two decades, membrane processes have gained a lot of attention for the separation of gases. They have been found to be very suitable for wide scale applications owing to their reasonable cost, good selectivity and easily engineered modules. This critical review primarily focuses on the various aspects of membrane processes related to the separation of biogas, more in specific CO(2) and H(2)S removal from CH(4) and H(2) streams. Considering the limitations of inorganic materials for membranes, the present review will only focus on work done with polymeric materials. An overview on the performance of commercial membranes and lab-made membranes highlighting the problems associated with their applications will be given first. The development studies carried out to enhance the performance of membranes for gas separation will be discussed in the subsequent section. This review has been broadly divided into three sections (i) performance of commercial polymeric membranes (ii) performance of lab-made polymeric membranes and (iii) performance of mixed matrix membranes (MMMs) for gas separations. It will include structural modifications at polymer level, polymer blending, as well as synthesis of mixed matrix membranes, for which addition of silane-coupling agents and selection of suitable fillers will receive special attention. Apart from an overview of the different membrane materials, the study will also highlight the effects of different operating conditions that eventually decide the performance and longevity of membrane applications in gas separations. The discussion will be largely restricted to the studies carried out on polyimide (PI), cellulose acetate (CA), polysulfone (PSf) and polydimethyl siloxane (PDMS) membranes, as these membrane materials have been most widely used for commercial applications. Finally, the most important strategies that would ensure new commercial applications will be discussed (156 references).

Radiation-engineered nanomaterials. The role of the IAEA in coordinating research

International Nuclear Information System (INIS)

Haji-Saeid, M.; Safrany, A.; Sampa, M.H. de O.; Ramamoorthy, N.

2011-01-01

Complete text of publication follows. Radiation technologies, already established in materials processing, have properties uniquely for the creation of new functional materials on the nanoscale, both in 'top-to-bottom' and 'bottom-up' approaches. For example, controlled radiation degradation may be used for fabrication of nanoporous and nanostructured surfaces and membranes; while radiation polymerization, crosslinking and grafting could produce functional polymeric, metallic and semiconductor nanoparticles, functional nanostructured surfaces and nanocomposites. Applications for such nanostructured materials are manifold, from 3D structures, templates for nanowire fabrication, supports for purification, and proton exchange membranes, to imaging, diagnostics, targeted drug and gene delivery, wound healing and cell sheet engineering. Considering the significant potential as well as the already demonstrated successful applications in using radiation methods for synthesis and characterization of nano-sized materials as well as the interdisciplinary nature of nanotechnology, and in order to facilitate the coordination between radiation-based research groups and nanotechnology centres, the IAEA has organized a number of consultancy meetings, training courses and workshops. Additionally, a coordinated research project entitled 'Nanoscale Radiation Engineering of Advanced Materials for Potential Biomedical applications' in progress, under which 17 IAEA Member States institutions work together to develop radiolytic methodologies for synthesis of nanoparticles and nanoporous membranes; polymeric, inorganic and hybrid nanocarriers for various healthcare applications. This presentation will describe the present activities of the IAEA and plans for future supports for fostering development and application of radiation-engineered functional nanomaterials.

Impact of type 1 diabetes mellitus on the family is reduced with the medical home, care coordination, and family-centered care.

Science.gov (United States)

Katz, Michelle L; Laffel, Lori M; Perrin, James M; Kuhlthau, Karen

2012-05-01

To examine whether the medical home, care coordination, or family-centered care was associated with less impact of type 1 diabetes mellitus (T1D) on families' work, finances, time, and school attendance. With the 2005 to 2006 National Survey of Children with Special Health Care Needs, we compared impact in children with T1D (n = 583) with that in children with other special health care needs (n = 39 944) and children without special health care needs (n = 4945). We modeled the associations of the medical home, care coordination, and family-centered care with family impact in T1D. Seventy-five percent of families of children with T1D reported a major impact compared with 45% of families of children with special health care needs (P families of children without special health care needs (P families of children with T1D, 35% reported restricting work, 38% reported financial impact, 41% reported medical expenses >$1000/year, 24% reported spending ≥11 hours/week caring or coordination care, and 20% reported ≥11 school absences/year. The medical home, care coordination, and family-centered care were associated with less work and financial impact. In childhood T1D, most families experience major impact. Better systems of health care delivery may help families reduce some of this impact. Copyright © 2012 Mosby, Inc. All rights reserved.

Homeoviscous adaptation and the regulation of membrane lipids

DEFF Research Database (Denmark)

Ernst, Robert; Ejsing, Christer S; Antonny, Bruno

2016-01-01

Biological membranes are complex and dynamic assemblies of lipids and proteins. Poikilothermic organisms including bacteria, fungi, reptiles, and fish do not control their body temperature and must adapt their membrane lipid composition in order to maintain membrane fluidity in the cold. This ada......Biological membranes are complex and dynamic assemblies of lipids and proteins. Poikilothermic organisms including bacteria, fungi, reptiles, and fish do not control their body temperature and must adapt their membrane lipid composition in order to maintain membrane fluidity in the cold....... This adaptive response was termed homeoviscous adaptation and has been frequently studied with a specific focus on the acyl chain composition of membrane lipids. Massspectrometry-based lipidomics can nowadays provide more comprehensive insights into the complexity of lipid remodeling during adaptive responses...... such as neurons maintain unique lipid compositions with specific physicochemical properties. To date little is known about the sensory mechanisms regulating the acyl chain profile in such specialized cells or during adaptive responses. Here we summarize our current understanding of lipid metabolic networks...

Fluxes of water through aquaporin 9 weaken membrane-cytoskeleton anchorage and promote formation of membrane protrusions.

Directory of Open Access Journals (Sweden)

Thommie Karlsson

Full Text Available All modes of cell migration require rapid rearrangements of cell shape, allowing the cell to navigate within narrow spaces in an extracellular matrix. Thus, a highly flexible membrane and a dynamic cytoskeleton are crucial for rapid cell migration. Cytoskeleton dynamics and tension also play instrumental roles in the formation of different specialized cell membrane protrusions, viz. lamellipodia, filopodia, and membrane blebs. The flux of water through membrane-anchored water channels, known as aquaporins (AQPs has recently been implicated in the regulation of cell motility, and here we provide novel evidence for the role of AQP9 in the development of various forms of membrane protrusion. Using multiple imaging techniques and cellular models we show that: (i AQP9 induced and accumulated in filopodia, (ii AQP9-associated filopodial extensions preceded actin polymerization, which was in turn crucial for their stability and dynamics, and (iii minute, local reductions in osmolarity immediately initiated small dynamic bleb-like protrusions, the size of which correlated with the reduction in osmotic pressure. Based on this, we present a model for AQP9-induced membrane protrusion, where the interplay of water fluxes through AQP9 and actin dynamics regulate the cellular protrusive and motile activity of cells.

Biomimetic polymeric membranes for water treatment

DEFF Research Database (Denmark)

Habel, Joachim Erich Otto

This project is about the interplay of the three major components of aquaporin based biomimetic polymeric membranes (ABPMs): Aquaporins (AQPs), amphiphilic block copolymers, serving as a vesicular matrix for the hydrophobic AQP exterior (proteopolymersomes) and a polymeric membrane as embedment....... The interplay of proteopolymersomes and polymeric mesh support (in this case polyethersulfone, PES) was examined via integration of proteopolymersomes in an active layer (AL) formed by interfacial polymerisation between a linker molecule in aqueous phase and another in organic phase on top of the PES....... The resulting thin-film composite (TFC) membrane was analyzed via cross-flow forward osmosis (FO), scanning electron microscopy (SEM), fourier-transformed infrared spectroscopy (FTIR), as well as in the non-supported form over FTIR and a specialized microfluidic visualization approach. Where no clear dierences...

Polyrhodanine modified anodic aluminum oxide membrane for heavy metal ions removal.

Science.gov (United States)

Song, Jooyoung; Oh, Hyuntaek; Kong, Hyeyoung; Jang, Jyongsik

2011-03-15

Polyrhodanine was immobilized onto the inner surface of anodic aluminum oxide (AAO) membrane via vapor deposition polymerization method. The polyrhodanine modified membrane was applied to remove heavy metal ions from aqueous solution because polyrhodanine could be coordinated with specific metal ions. Several parameters such as initial metal concentration, contact time and metal species were evaluated systematically for uptake efficiencies of the fabricated membrane under continuous flow condition. Adsorption isotherms of Hg(II) ion on the AAO-polyrhodanine membrane were analyzed with Langmuir and Freundlich isotherm models. The adsorption rate of Hg(II) ion on the membrane was obeyed by a pseudo-second order equation, indicating the chemical adsorption. The maximum removal capacity of Hg(II) ion onto the fabricated membrane was measured to be 4.2 mmol/g polymer. The AAO-polyrhodanine membrane had also remarkable uptake performance toward Ag(I) and Pb(II) ions. Furthermore, the polyrhodanine modified membrane could be recycled after recovery process. These results demonstrated that the polyrhodanine modified AAO membrane provided potential applications for removing the hazardous heavy metal ions from wastewater. Copyright © 2011 Elsevier B.V. All rights reserved.

Diamond free-standing porous membranes; Membranas porosas auto-sustentadas de diamante

Energy Technology Data Exchange (ETDEWEB)

Mammana, Victor Pellegrini

1996-07-01

A method for fabricating free-standing diamond membranes with controlled porous density and size, using silicon molds is presented. This method has advantages compared to those developed until now, specially concerning to its simplicity and membrane characteristics. The process is described step by step, and a morphological study of the porous is done, in order to identify the relevance of each step, in the membrane characteristics. Finally, a proposal is made to improve the process in the future. (author)

Fabrication of TiO_2-modified polytetrafluoroethylene ultrafiltration membranes via plasma-enhanced surface graft pretreatment

International Nuclear Information System (INIS)

Qian, Yingjia; Chi, Lina; Zhou, Weili; Yu, Zhenjiang; Zhang, Zhongzhi; Zhang, Zhenjia; Jiang, Zheng

2016-01-01

Graphical abstract: - Highlights: • Multifunctional TiO_2/PAA/PTFE ultrafiltration membrane was fabricated via tight coating of TiO_2 functional layer onto the plasma-assisted graft of PAA on PTFE. • The high water flux rate, remarkable enhanced ultrafiltration performance and excellent self-cleaning ability were demonstrated. • The formation of COO−Ti bidentate coordination between TiO_2 and PAA was responsible for the successful coating. - Abstract: Surface hydrophilic modification of polymer ultrafiltration membrane using metal oxide represents an effective yet highly challenging solution to improve water flux and antifouling performance. Via plasma-enhanced graft of poly acryl acid (PAA) prior to coating TiO_2, we successfully fixed TiO_2 functional thin layer on super hydrophobic polytetrafluoroethylene (PTFE) ultrafiltration (UF) membranes. The characterization results evidenced TiO_2 attached on the PTFE-based UF membranes through the chelating bidentate coordination between surface-grafted carboxyl group and Ti"4"+. The TiO_2 surface modification may greatly reduce the water contact angle from 115.8° of the PTFE membrane to 35.0° without degradation in 30-day continuous filtration operations. The novel TiO_2/PAA/PTFE membranes also exhibited excellent antifouling and self-cleaning performance due to the intrinsic hydrophilicity and photocatalysis properties of TiO_2, which was further confirmed by the photo-degradation of MB under Xe lamp irradiation.

THE PARENTING COORDINATOR: A NEW PROFESSIONAL ROLE FOR THE FORENSIC PSYCHOLOGIST

OpenAIRE

Carles Rodríguez-Domínguez; Xavier Carbonell

2014-01-01

The role of the parenting coordinator in the United States was born in the 90s, to help families to resolve conflicts when the couple’s separation means that everyday disputes have not been able to be resolved, producing a high level of conflict and a large number of interventions with social workers, as well as health and/or legal interventions. The aim of this study is to present the role of the parenting coordinator, a highly specialized person that intervenes effectively in these famil...

Network Performance and Coordination in the Health, Education, Telecommunications System. Satellite Technology Demonstration, Technical Report No. 0422.

Science.gov (United States)

Braunstein, Jean; Janky, James M.

This paper describes the network coordination for the Health, Education, Telecommunications (HET) system. Specifically, it discusses HET network performance as a function of a specially-developed coordination system which was designed to link terrestrial equipment to satellite operations centers. Because all procedures and equipment developed for…

Effect of Mass-Transport Limitations on the Performance of a Packed Bed Membrane Reactor for Partial Oxidations. Transport from the Membrane to the Packed Bed

NARCIS (Netherlands)

van Sint Annaland, M.; Kurten, U.; Kuipers, J.A.M.

2007-01-01

With a packed bed membrane reactor, the product yield can be significantly enhanced for partial oxidation systems, via distributive addition of oxygen to the reaction mixture along the axial coordinate of the reactor, provided that the reaction order in oxygen of the formation rate of the target

Effect of mass-transport limitations on the performance of a packed bed membrane reactor for partial oxidations. Transport from the membrane to the packed bed

NARCIS (Netherlands)

Sint Annaland, van M.; Kurten, U.; Kuipers, J.A.M.

2007-01-01

With a packed bed membrane reactor, the product yield can be significantly enhanced for partial oxidation systems, via distributive addition of oxygen to the reaction mixture along the axial coordinate of the reactor, provided that the reaction order in oxygen of the formation rate of the target

Access to patient-centered medical home among Ohio's Children with Special Health Care Needs.

Science.gov (United States)

Conrey, Elizabeth J; Seidu, Dazar; Ryan, Norma J; Chapman, Dj Sam

2013-06-01

Medical homes deliver primary care that is accessible, continuous, comprehensive, family centered, coordinated, compassionate and culturally effective. Children with special health care needs (CSHCN) require a wide range of support to maintain health, making medical home access particularly important. We sought to understand independent risk factors for lacking access. We analyzed Ohio, USA data from the National Survey of Children with Special Health Care Needs (2005-2006). Among CSHCN, 55.6% had medical home access. The proportion achieving each medical home component was highest for having a personal doctor/nurse and lowest for receiving coordinated care, family-centered care and referrals. Specific subsets of CSHCN were significantly and independently more likely to lack medical home access: Hispanic (AOR=3.08), moderate/high severity of difficulty (AOR=2.84), and any public insurance (AOR=1.60). Efforts to advance medical home access must give special attention to these CSHCN populations and improvements must be made to referral access, family-centered care, and care coordination.

Coordination of substrate binding and ATP hydrolysis in Vps4-mediated ESCRT-III disassembly.

Science.gov (United States)

Davies, Brian A; Azmi, Ishara F; Payne, Johanna; Shestakova, Anna; Horazdovsky, Bruce F; Babst, Markus; Katzmann, David J

2010-10-01

ESCRT-III undergoes dynamic assembly and disassembly to facilitate membrane exvagination processes including multivesicular body (MVB) formation, enveloped virus budding, and membrane abscission during cytokinesis. The AAA-ATPase Vps4 is required for ESCRT-III disassembly, however the coordination of Vps4 ATP hydrolysis with ESCRT-III binding and disassembly is not understood. Vps4 ATP hydrolysis has been proposed to execute ESCRT-III disassembly as either a stable oligomer or an unstable oligomer whose dissociation drives ESCRT-III disassembly. An in vitro ESCRT-III disassembly assay was developed to analyze Vps4 function during this process. The studies presented here support a model in which Vps4 acts as a stable oligomer during ATP hydrolysis and ESCRT-III disassembly. Moreover, Vps4 oligomer binding to ESCRT-III induces coordination of ATP hydrolysis at the level of individual Vps4 subunits. These results suggest that Vps4 functions as a stable oligomer that acts upon individual ESCRT-III subunits to facilitate ESCRT-III disassembly.

Mechanical properties of 3D printed warped membranes

Science.gov (United States)

Kosmrlj, Andrej; Xiao, Kechao; Weaver, James C.; Vlassak, Joost J.; Nelson, David R.

2015-03-01

We explore how a frozen background metric affects the mechanical properties of solid planar membranes. Our focus is a special class of ``warped membranes'' with a preferred random height profile characterized by random Gaussian variables h (q) in Fourier space with zero mean and variance q-m . It has been shown theoretically that in the linear response regime, this quenched random disorder increases the effective bending rigidity, while the Young's and shear moduli are reduced. Compared to flat plates of the same thickness t, the bending rigidity of warped membranes is increased by a factor hv / t while the in-plane elastic moduli are reduced by t /hv , where hv =√{ } describes the frozen height fluctuations. Interestingly, hv is system size dependent for warped membranes characterized with m > 2 . We present experimental tests of these predictions, using warped membranes prepared via high resolution 3D printing.

Fabrication of Polybenzimidazole/Palladium Nanoparticles Hollow Fiber Membranes for Hydrogen Purification

KAUST Repository

Villalobos, Luis Francisco; Hilke, Roland; Akhtar, Faheem Hassan; Peinemann, Klaus-Viktor

2017-01-01

in the form of ions that coordinate to the imidazole groups of the polymer. This is attractive for membrane production because agglomeration of nanoparticles is minimized and the high-cost metal is incorporated in only the selective layer—where it is required

Controlled release of mitomycin C from PHEMAH-Cu(II) cryogel membranes.

Science.gov (United States)

Bakhshpour, Monireh; Yavuz, Handan; Denizli, Adil

2018-02-19

Molecular imprinting technique was used for the preparation of antibiotic and anti-neoplastic chemotherapy drug (mitomycin C) imprinted cryogel membranes (MMC-ICM). The membranes were synthezied by using metal ion coordination interactions with N-methacryloyl-(l)-histidine methyl ester (MAH) functional monomer and template molecules (i.e. MMC). The 2-hydroxyethyl methacrylate (HEMA) monomer and methylene bisacrylamide (MBAAm) crosslinker were used for the preparation of mitomycin C imprinted cryogel membranes by radical suspension polymerization technique. The imprinted cryogel membranes were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) and swelling degree measurements. Cytotoxicity of MMC-ICMs was investigated using mouse fibroblast cell line L929. Time-dependent release of MMC was demonstrated within 150 h from cryogel membranes. Cryogels demonstrated very high MMC loading efficiency (70-80%) and sustained MMC release over hours.

A Real-World Community Health Worker Care Coordination Model for High-Risk Children.

Science.gov (United States)

Martin, Molly A; Perry-Bell, Kenita; Minier, Mark; Glassgow, Anne Elizabeth; Van Voorhees, Benjamin W

2018-04-01

Health care systems across the United States are considering community health worker (CHW) services for high-risk patients, despite limited data on how to build and sustain effective CHW programs. We describe the process of providing CHW services to 5,289 at-risk patients within a state-run health system. The program includes 30 CHWs, six care coordinators, the Director of Care Coordination, the Medical Director, a registered nurse, mental health specialists, and legal specialists. CHWs are organized into geographic and specialized teams. All CHWs receive basic training that includes oral and mental health; some receive additional disease-specific training. CHWs develop individualized care coordination plans with patients. The implementation of these plans involves delivery of a wide range of social service and coordination support. The number of CHW contacts is determined by patient risk. CHWs spend about 60% of their time in an office setting. To deliver the program optimally, we had to develop multiple CHW job categories that allow for CHW specialization. We created new technology systems to manage operations. Field issues resulted in program changes to improve service delivery and ensure safety. Our experience serves as a model for how to integrate CHWs into clinical and community systems.

Equilibrium fluctuation relations for voltage coupling in membrane proteins.

Science.gov (United States)

Kim, Ilsoo; Warshel, Arieh

2015-11-01

A general theoretical framework is developed to account for the effects of an external potential on the energetics of membrane proteins. The framework is based on the free energy relation between two (forward/backward) probability densities, which was recently generalized to non-equilibrium processes, culminating in the work-fluctuation theorem. Starting from the probability densities of the conformational states along the "voltage coupling" reaction coordinate, we investigate several interconnected free energy relations between these two conformational states, considering voltage activation of ion channels. The free energy difference between the two conformational states at zero (depolarization) membrane potential (i.e., known as the chemical component of free energy change in ion channels) is shown to be equivalent to the free energy difference between the two "equilibrium" (resting and activated) conformational states along the one-dimensional voltage couplin reaction coordinate. Furthermore, the requirement that the application of linear response approximation to the free energy functionals of voltage coupling should satisfy the general free energy relations, yields a novel closed-form expression for the gating charge in terms of other basic properties of ion channels. This connection is familiar in statistical mechanics, known as the equilibrium fluctuation-response relation. The theory is illustrated by considering the coupling of a unit charge to the external voltage in the two sites near the surface of membrane, representing the activated and resting states. This is done using a coarse-graining (CG) model of membrane proteins, which includes the membrane, the electrolytes and the electrodes. The CG model yields Marcus-type voltage dependent free energy parabolas for the response of the electrostatic environment (electrolytes etc.) to the transition from the initial to the final configuratinal states, leading to equilibrium free energy difference and free

Structure analysis in algorithms and programs. Generator of coordinates of equivalent points. (Collected programs)

International Nuclear Information System (INIS)

Matyushenko, N.N.; Titov, Yu.G.

1982-01-01

Programs of atom coordinate generation and space symmetry groups in a form of equivalent point systems are presented. Programs of generation and coordinate output from an on-line storage are written in the FORTRAN language for the ES computer. They may be used in laboratories specialized in studying atomic structure and material properties, in colleges and by specialists in other fields of physics and chemistry

Protein receptor-independent plasma membrane remodeling by HAMLET

DEFF Research Database (Denmark)

Nadeem, Aftab; Sanborn, Jeremy; Gettel, Douglas L.

2015-01-01

A central tenet of signal transduction in eukaryotic cells is that extra-cellular ligands activate specific cell surface receptors, which orchestrate downstream responses. This "protein-centric" view is increasingly challenged by evidence for the involvement of specialized membrane domains...... in signal transduction. Here, we propose that membrane perturbation may serve as an alternative mechanism to activate a conserved cell-death program in cancer cells. This view emerges from the extraordinary manner in which HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) kills a wide range...... of tumor cells in vitro and demonstrates therapeutic efficacy and selectivity in cancer models and clinical studies. We identify a "receptor independent" transformation of vesicular motifs in model membranes, which is paralleled by gross remodeling of tumor cell membranes. Furthermore, we find that HAMLET...

Use of membrane separation processes for the separation of radionuclides from liquid and gas streams

International Nuclear Information System (INIS)

Vladisavljevic, G.T.; Rajkovic, M.B.

1999-01-01

Use of membranes for the separation and recovery of radionuclides from contaminated liquid and gas streams has been discussed in this paper. The special attention has been paid to the use of ion-exchange membranes for electrodialysis and Donnan dialysis, as well as the use of facilitated liquid membranes for liquid pertraction. (author)

Membrane separation using nano-pores; Nano poa wo riyoshita makubunri

Energy Technology Data Exchange (ETDEWEB)

Manabe, S. [Fukuoka Women`s Univ., Fukuoka (Japan)

1995-08-01

The membrane constituted by nano-pore only (NF membrane) is sold on the market recently as the membranes used for the matter separations in addition to the reverse osmosis membrane for changing seawater into fresh water, dialysis membrane used for artificial kidney, ultrafiltration membrane used for the separation and condensation of protein and the micro-filter used for removing microbe. It is possible for the membrane constituted by nano-pore to remove the virus with the size being from 20 to 300 nm. In this paper, the pore structure of NF membrane is explained, and then its application as the membrane for removing virus is described. Especially, it is possible for NF membrane to remove the virus with smallest size (parvovirus, etc.), prion albumen (bovine serum pathogen, etc.) and the special gene such as cancer, and it is further applied to the condensation and refining of virus and genes. The broader application of nano-pore to the control of the transportation of micro-particles in the future is expected. 3 refs., 2 figs.

Characterisation of detergent-insoluble membranes in pollen tubes of Nicotiana tabacum (L.

Directory of Open Access Journals (Sweden)

Alessandra Moscatelli

2015-02-01

Full Text Available Pollen tubes are the vehicle for sperm cell delivery to the embryo sac during fertilisation of Angiosperms. They provide an intriguing model for unravelling mechanisms of growing to extremes. The asymmetric distribution of lipids and proteins in the pollen tube plasma membrane modulates ion fluxes and actin dynamics and is maintained by a delicate equilibrium between exocytosis and endocytosis. The structural constraints regulating polarised secretion and asymmetric protein distribution on the plasma membrane are mostly unknown. To address this problem, we investigated whether ordered membrane microdomains, namely membrane rafts, might contribute to sperm cell delivery. Detergent insoluble membranes, rich in sterols and sphingolipids, were isolated from tobacco pollen tubes. MALDI TOF/MS analysis revealed that actin, prohibitins and proteins involved in methylation reactions and in phosphoinositide pattern regulation are specifically present in pollen tube detergent insoluble membranes. Tubulins, voltage-dependent anion channels and proteins involved in membrane trafficking and signalling were also present. This paper reports the first evidence of membrane rafts in Angiosperm pollen tubes, opening new perspectives on the coordination of signal transduction, cytoskeleton dynamics and polarised secretion.

Is there a map between Galilean relativity and special relativity?

OpenAIRE

Shariati, Ahmad; Jafari, N.

2014-01-01

Mandanici has provided a map which he claims to be a two way map between Galilean relativity and special relativity. We argue that this map is simply a curvilinear coordinate system on a subset of the two-dimensional Minkowski space-time, and is not a two way map between 1+1 dimensional Galilean relativity and 1+1 dimensional special relativity.

Toward the Structure of Dynamic Membrane-Anchored Actin Networks

Science.gov (United States)

Weber, Igor

2007-01-01

In the cortex of a motile cell, membrane-anchored actin filaments assemble into structures of varying shape and function. Filopodia are distinguished by a core of bundled actin filaments within finger-like extensions of the membrane. In a recent paper by Medalia et al1 cryo-electron tomography has been used to reconstruct, from filopodia of Dictyostelium cells, the 3-dimensional organization of actin filaments in connection with the plasma membrane. A special arrangement of short filaments converging toward the filopod's tip has been called a “terminal cone”. In this region force is applied for protrusion of the membrane. Here we discuss actin organization in the filopodia of Dictyostelium in the light of current views on forces that are generated by polymerizing actin filaments, and on the resistance of membranes against deformation that counteracts these forces. PMID:19262130

MAL Is a Regulator of the Recruitment of Myelin Protein PLP to Membrane Microdomains

NARCIS (Netherlands)

Bijlard, Marjolein; de Jonge, Jenny C.; Klunder, Bert; Nomden, Anita; Hoekstra, Dick; Baron, Wia

2016-01-01

In oligodendrocytes (OLGs), an indirect, transcytotic pathway is mediating transport of de novo synthesized PLP, a major myelin specific protein, from the apical-like plasma membrane to the specialized basolateral-like myelin membrane to prevent its premature compaction. MAL is a well-known

Fast algorithms for coordinate processors in Galois field for multiplicity t = 4.5 and t > 5

International Nuclear Information System (INIS)

Nikityuk, N.M.

1989-01-01

Fast algorithms for solving the coordinate equations for special-purpose processors at multiplicity t = 4.5 and t > 5 are described. Block diagrams of coordinate processor for t 4 in Galois field GF(2 m ) is presented which is solved by a table method. Economical algorithms for solving the coordinate equations by serial methods at t > 5 are described. The algorithms and devices proposed could be applied when creating fast processors in high energy physics spectrometers. 9 refs.; 3 figs

Relating transport modeling to nanofiltration membrane fabrication: Navigating the permeability-selectivity trade-off in desalination pretreatment

OpenAIRE

Labban, Omar; Lienhard, John H

2018-01-01

Faced with a pressing need for membranes with a higher permeability and selectivity, the field of membrane technology can benefit from a systematic framework for designing membranes with the necessary physical characteristics. In this work, we present an approach through which transport modeling is employed in fabricating specialized nanofiltration membranes, that experimentally demonstrate enhanced selectivity. Specifically, the Donnan-Steric Pore Model with dielectric exclusion (DSPM-DE) is...

Chronophin coordinates cell leading edge dynamics by controlling active cofilin levels

Science.gov (United States)

Delorme-Walker, Violaine; Seo, Ji-Yeon; Gohla, Antje; Fowler, Bruce; Bohl, Ben; DerMardirossian, Céline

2015-01-01

Cofilin, a critical player of actin dynamics, is spatially and temporally regulated to control the direction and force of membrane extension required for cell locomotion. In carcinoma cells, although the signaling pathways regulating cofilin activity to control cell direction have been established, the molecular machinery required to generate the force of the protrusion remains unclear. We show that the cofilin phosphatase chronophin (CIN) spatiotemporally regulates cofilin activity at the cell edge to generate persistent membrane extension. We show that CIN translocates to the leading edge in a PI3-kinase–, Rac1-, and cofilin-dependent manner after EGF stimulation to activate cofilin, promotes actin free barbed end formation, accelerates actin turnover, and enhances membrane protrusion. In addition, we establish that CIN is crucial for the balance of protrusion/retraction events during cell migration. Thus, CIN coordinates the leading edge dynamics by controlling active cofilin levels to promote MTLn3 cell protrusion. PMID:26324884

Transmembrane peptides as sensors of the membrane physical state

Science.gov (United States)

Piotto, Stefano; Di Biasi, Luigi; Sessa, Lucia; Concilio, Simona

2018-05-01

Cell membranes are commonly considered fundamental structures having multiple roles such as confinement, storage of lipids, sustain and control of membrane proteins. In spite of their importance, many aspects remain unclear. The number of lipid types is orders of magnitude larger than the number of amino acids, and this compositional complexity is not clearly embedded in any membrane model. A diffused hypothesis is that the large lipid palette permits to recruit and organize specific proteins controlling the formation of specialized lipid domains and the lateral pressure profile of the bilayer. Unfortunately, a satisfactory knowledge of lipid abundance remains utopian because of the technical difficulties in isolating definite membrane regions. More importantly, a theoretical framework where to fit the lipidomic data is still missing. In this work, we wish to utilize the amino acid sequence and frequency of the membrane proteins as bioinformatics sensors of cell bilayers. The use of an alignment-free method to find a correlation between the sequences of transmembrane portion of membrane proteins with the membrane physical state suggested a new approach for the discovery of antimicrobial peptides.

THE PARENTING COORDINATOR: A NEW PROFESSIONAL ROLE FOR THE FORENSIC PSYCHOLOGIST

Directory of Open Access Journals (Sweden)

Carles Rodríguez-Domínguez

2014-09-01

Full Text Available The role of the parenting coordinator in the United States was born in the 90s, to help families to resolve conflicts when the couple’s separation means that everyday disputes have not been able to be resolved, producing a high level of conflict and a large number of interventions with social workers, as well as health and/or legal interventions. The aim of this study is to present the role of the parenting coordinator, a highly specialized person that intervenes effectively in these families to minimize interparental conflict, to the benefit of the children and also the parents. The experience of the role of the parenting coordinator in other countries has been a useful model in the reduction and resolution of conflicts in the family courts.

Photocatalytic Nanofiltration Membranes with Self-Cleaning Property for Wastewater Treatment

Energy Technology Data Exchange (ETDEWEB)

Lv, Yan [MOE Key Laboratory of Macromolecular Synthesis and Functionalization, and Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 China; Zhang, Chao [MOE Key Laboratory of Macromolecular Synthesis and Functionalization, and Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 China; He, Ai [MOE Key Laboratory of Macromolecular Synthesis and Functionalization, and Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 China; Yang, Shang-Jin [MOE Key Laboratory of Macromolecular Synthesis and Functionalization, and Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 China; Wu, Guang-Peng [MOE Key Laboratory of Macromolecular Synthesis and Functionalization, and Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 China; Darling, Seth B. [Nanoscience & Technology Division, Argonne National Laboratory, 9700 South Cass Avenue Lemont IL 60439 USA; Institute for Molecular Engineering, University of Chicago, Chicago IL 60637 USA; Xu, Zhi-Kang [MOE Key Laboratory of Macromolecular Synthesis and Functionalization, and Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 China

2017-05-16

Membrane fouling is one of the most severe problems restricting membrane separation technology for wastewater treatment. This work reports a photocatalytic nanofiltration membrane (NFM) with self-cleaning property fabricated using a facile biomimetic mineralization process. In this strategy, a polydopamine (PDA)/polyethyleneimine (PEI) intermediate layer is fabricated on an ultrafiltration membrane via a co-deposition method followed by mineralization of a photocatalytic layer consisting of beta-FeOOH nanorods. The PDA-PEI layer acts both as a nanofiltration selective layer and an intermediate layer for anchoring the beta-FeOOH nanorods via strong coordination complexes between Fe3+ and catechol groups. In visible light, the beta-(F)eOOH layer exhibits efficient photocatalytic activity for degrading dyes through the photo-Fenton reaction in the presence of hydrogen peroxide, endowing the NFM concurrently with effective nanofiltration performance and self-cleaning capability. Moreover, the mineralized NFMs exhibit satisfactory stability under simultaneous filtration and photocatalysis processing, showing great potential in advanced wastewater treatment.

Mechanisms underlying anomalous diffusion in the plasma membrane.

Science.gov (United States)

Krapf, Diego

2015-01-01

The plasma membrane is a complex fluid where lipids and proteins undergo diffusive motion critical to biochemical reactions. Through quantitative imaging analyses such as single-particle tracking, it is observed that diffusion in the cell membrane is usually anomalous in the sense that the mean squared displacement is not linear with time. This chapter describes the different models that are employed to describe anomalous diffusion, paying special attention to the experimental evidence that supports these models in the plasma membrane. We review models based on anticorrelated displacements, such as fractional Brownian motion and obstructed diffusion, and nonstationary models such as continuous time random walks. We also emphasize evidence for the formation of distinct compartments that transiently form on the cell surface. Finally, we overview heterogeneous diffusion processes in the plasma membrane, which have recently attracted considerable interest. Copyright © 2015. Published by Elsevier Inc.

Oilfield Produced Water Reuse and Reinjection with Membrane

Directory of Open Access Journals (Sweden)

Siagian Utjok W.R.

2018-01-01

Full Text Available Produced water has become a global environmental issue due to its huge volume and toxicity that may pose detrimental effects on receiving environment. Several approaches have been proposed to provide a strategy for produced water handling such as reinjection, reuse, or discharge. With various advantages, membrane technology has been increasingly used in produced water treatment replacing the conventional technologies. However, fouling is a major drawback of membrane processes in this application which needs to be controlled. This paper gives an overview and comparison of different produced water management. Special attention is given to produced water treatment for reuse purpose. Furthermore, the use of membrane processes in produced water reuse including performance, challenges, and future outlook are discussed.

Fabrication of TiO{sub 2}-modified polytetrafluoroethylene ultrafiltration membranes via plasma-enhanced surface graft pretreatment

Energy Technology Data Exchange (ETDEWEB)

Qian, Yingjia [School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240 (China); Chi, Lina, E-mail: lnchi@sjtu.edu.cn [School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240 (China); Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ (United Kingdom); Zhou, Weili; Yu, Zhenjiang [School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240 (China); Zhang, Zhongzhi [College of Chemical Engineering, China University of Petroleum, Beijing 102249 (China); Zhang, Zhenjia [School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240 (China); Jiang, Zheng, E-mail: z.jiang@soton.ac.uk [Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ (United Kingdom)

2016-01-01

Graphical abstract: - Highlights: • Multifunctional TiO{sub 2}/PAA/PTFE ultrafiltration membrane was fabricated via tight coating of TiO{sub 2} functional layer onto the plasma-assisted graft of PAA on PTFE. • The high water flux rate, remarkable enhanced ultrafiltration performance and excellent self-cleaning ability were demonstrated. • The formation of COO−Ti bidentate coordination between TiO{sub 2} and PAA was responsible for the successful coating. - Abstract: Surface hydrophilic modification of polymer ultrafiltration membrane using metal oxide represents an effective yet highly challenging solution to improve water flux and antifouling performance. Via plasma-enhanced graft of poly acryl acid (PAA) prior to coating TiO{sub 2}, we successfully fixed TiO{sub 2} functional thin layer on super hydrophobic polytetrafluoroethylene (PTFE) ultrafiltration (UF) membranes. The characterization results evidenced TiO{sub 2} attached on the PTFE-based UF membranes through the chelating bidentate coordination between surface-grafted carboxyl group and Ti{sup 4+}. The TiO{sub 2} surface modification may greatly reduce the water contact angle from 115.8° of the PTFE membrane to 35.0° without degradation in 30-day continuous filtration operations. The novel TiO{sub 2}/PAA/PTFE membranes also exhibited excellent antifouling and self-cleaning performance due to the intrinsic hydrophilicity and photocatalysis properties of TiO{sub 2}, which was further confirmed by the photo-degradation of MB under Xe lamp irradiation.

All the same: isoporous membranes for water purification

NARCIS (Netherlands)

Vriezekolk, Erik

2016-01-01

In this thesis, the focus is on three approaches that allow fabrication of films and membranes that contain ordered and uniform pores with pore sizes in the ultrafiltration range. Special attention is given to the tuning of pore sizes by varying simple parameters during the fabrication process.

The distribution of cerebral activity related to visuomotor coordination indicating perceptual and executional specialization

NARCIS (Netherlands)

de Jong, BM; Frackowiak, RSJ; Willemsen, ATM; Paans, AMJ

The distribution of increased regional cerebral blood flow (rCBF) related to visuomotor coordination was studied by means of positron emission tomography (PET) in normal subjects. An experimental condition, in which a vertically presented zigzag figure had to be copied in a horizontal orientation,

Structural basis for catalysis at the membrane-water interface.

Science.gov (United States)

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

2017-11-01

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

Monoolein lipid phases as incorporation and enrichment materials for membrane protein crystallization.

Directory of Open Access Journals (Sweden)

Ellen Wallace

Full Text Available The crystallization of membrane proteins in amphiphile-rich materials such as lipidic cubic phases is an established methodology in many structural biology laboratories. The standard procedure employed with this methodology requires the generation of a highly viscous lipidic material by mixing lipid, for instance monoolein, with a solution of the detergent solubilized membrane protein. This preparation is often carried out with specialized mixing tools that allow handling of the highly viscous materials while minimizing dead volume to save precious membrane protein sample. The processes that occur during the initial mixing of the lipid with the membrane protein are not well understood. Here we show that the formation of the lipidic phases and the incorporation of the membrane protein into such materials can be separated experimentally. Specifically, we have investigated the effect of different initial monoolein-based lipid phase states on the crystallization behavior of the colored photosynthetic reaction center from Rhodobacter sphaeroides. We find that the detergent solubilized photosynthetic reaction center spontaneously inserts into and concentrates in the lipid matrix without any mixing, and that the initial lipid material phase state is irrelevant for productive crystallization. A substantial in-situ enrichment of the membrane protein to concentration levels that are otherwise unobtainable occurs in a thin layer on the surface of the lipidic material. These results have important practical applications and hence we suggest a simplified protocol for membrane protein crystallization within amphiphile rich materials, eliminating any specialized mixing tools to prepare crystallization experiments within lipidic cubic phases. Furthermore, by virtue of sampling a membrane protein concentration gradient within a single crystallization experiment, this crystallization technique is more robust and increases the efficiency of identifying productive

Transport dynamics in membranes of photosynthetic purple bacteria

Science.gov (United States)

Caycedo, Felipe; Rodriguez, Ferney; Quiroga, Luis; Fassioli, Francesca; Johnson, Neil

2007-03-01

Photo-Syntethic Unit (PSU) of purple bacteria is conformed by three basic constituents: Light Harvesting Complex 2 (LH2) antenna complexes, where chromophores are distributed in a ring in close contact with caroteniods with a function of collecting light; LH1s, ring shaped structures of chromophores which harvest and funnel excitations to the Reaction Centre (RC), where phtosynthesis takes place. Studies concerning a single PSU have been capable of reproducing experimental transfer times, but incapable of explaining the fact that architecture LH2-LH1-RC of phototosynthetic membranes changes as light intensity conditions vary. The organization of antenna complexes in the membranes that support PSU seems to have its own functionality. A hopping model where excitations are transferred within a membrane is used, and populations of RC, LH1 and LH2 are investigated. Different statistics concerning arrival times of excitations that excite a single PSU are considered and compared with the global model where coordinates of a great portion of a membrane are included. The model permits in a classical basis to understand which parameters make photosynthesis in purple bateria efficient and reliable.

Membrane-lipid therapy: A historical perspective of membrane-targeted therapies - From lipid bilayer structure to the pathophysiological regulation of cells.

Science.gov (United States)

Escribá, Pablo V

2017-09-01

Our current understanding of membrane lipid composition, structure and functions has led to the investigation of their role in cell signaling, both in healthy and pathological cells. As a consequence, therapies based on the regulation of membrane lipid composition and structure have been recently developed. This novel field, known as Membrane Lipid Therapy, is growing and evolving rapidly, providing treatments that are now in use or that are being studied for their application to oncological disorders, Alzheimer's disease, spinal cord injury, stroke, diabetes, obesity, and neuropathic pain. This field has arisen from relevant discoveries on the behavior of membranes in recent decades, and it paves the way to adopt new approaches in modern pharmacology and nutrition. This innovative area will promote further investigation into membranes and the development of new therapies with molecules that target the cell membrane. Due to the prominent roles of membranes in the cells' physiology and the paucity of therapeutic approaches based on the regulation of the lipids they contain, it is expected that membrane lipid therapy will provide new treatments for numerous pathologies. The first on-purpose rationally designed molecule in this field, minerval, is currently being tested in clinical trials and it is expected to enter the market around 2020. However, it seems feasible that during the next few decades other membrane regulators will also be marketed for the treatment of human pathologies. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá. Copyright © 2017. Published by Elsevier B.V.

Transmembrane Peptides as Sensors of the Membrane Physical State

Directory of Open Access Journals (Sweden)

Stefano Piotto

2018-05-01

Full Text Available Cell membranes are commonly considered fundamental structures having multiple roles such as confinement, storage of lipids, sustain and control of membrane proteins. In spite of their importance, many aspects remain unclear. The number of lipid types is orders of magnitude larger than the number of amino acids, and this compositional complexity is not clearly embedded in any membrane model. A diffused hypothesis is that the large lipid palette permits to recruit and organize specific proteins controlling the formation of specialized lipid domains and the lateral pressure profile of the bilayer. Unfortunately, a satisfactory knowledge of lipid abundance remains utopian because of the technical difficulties in isolating definite membrane regions. More importantly, a theoretical framework where to fit the lipidomic data is still missing. In this work, we wish to utilize the amino acid sequence and frequency of the membrane proteins as bioinformatics sensors of cell bilayers. The use of an alignment-free method to find a correlation between the sequences of transmembrane portion of membrane proteins with the membrane physical state (MPS suggested a new approach for the discovery of antimicrobial peptides.

Analysis of full and cross-shaped boss membranes with piezoresistors in transversal strain configuration

International Nuclear Information System (INIS)

Tibrewala, A; Phataralaoha, A; Büttgenbach, S

2008-01-01

A 3D force sensor is developed using bulk silicon micromachining for measuring force in the sub-μN range. It is intended for use in high precision coordinate measuring machines. Full and cross-shaped boss membranes are fabricated, where the total chip size is 6.5 × 6.5 mm 2 . The full membrane is 3000 × 3000 µm 2 and the beams of the cross-shaped membrane are 900 × 700 µm 2 with 16 p-diffused piezoresistors in transversal strain configuration. The strains detected by the piezoresistors are measures of the three orthogonal components of the force applied at the tip of the stylus, which is glued on the center of the boss. When a vertical load is applied to the stylus, higher sensitivity is obtained for the cross-shaped membrane than for the full membrane

A preliminary study of aquaporin 1 immunolocalization in chronic subdural hematoma membranes.

Science.gov (United States)

Basaldella, Luca; Perin, Alessandro; Orvieto, Enrico; Marton, Elisabetta; Itskevich, David; Dei Tos, Angelo Paolo; Longatti, Pierluigi

2010-07-01

Aquaporin 1 (AQP1) is a molecular water channel expressed in many anatomical locations, particularly in epithelial barriers specialized in water transport. The aim of this study was to investigate AQP1 expression in chronic subdural hematoma (CSDH) membranes. In this preliminary study, 11 patients with CSDH underwent burr hole craniectomy and drainage. Membrane specimens were stained with a monoclonal antibody targeting AQP1 for immunohistochemical analysis. The endothelial cells of the sinusoid capillaries of the outer membranes exhibited an elevated immunoreactivity to AQP1 antibody compared to the staining intensity of specimens from the inner membrane and normal dura. These findings suggest that the outer membrane might be the source of the increased fluid accumulation responsible for chronic hematoma enlargement.

How synthetic membrane systems contribute to the understanding of lipid-driven endocytosis.

Science.gov (United States)

Schubert, Thomas; Römer, Winfried

2015-11-01

Synthetic membrane systems, such as giant unilamellar vesicles and solid supported lipid bilayers, have widened our understanding of biological processes occurring at or through membranes. Artificial systems are particularly suited to study the inherent properties of membranes with regard to their components and characteristics. This review critically reflects the emerging molecular mechanism of lipid-driven endocytosis and the impact of model membrane systems in elucidating the complex interplay of biomolecules within this process. Lipid receptor clustering induced by binding of several toxins, viruses and bacteria to the plasma membrane leads to local membrane bending and formation of tubular membrane invaginations. Here, lipid shape, and protein structure and valency are the essential parameters in membrane deformation. Combining observations of complex cellular processes and their reconstitution on minimal systems seems to be a promising future approach to resolve basic underlying mechanisms. This article is part of a Special Issue entitled: Mechanobiology. Copyright © 2015 Elsevier B.V. All rights reserved.

Recent Advances on Bioethanol Dehydration using Zeolite Membrane

Science.gov (United States)

Makertihartha, I. G. B. N.; Dharmawijaya, P. T.; Wenten, I. G.

2017-07-01

Renewable energy has gained increasing attention throughout the world. Bioethanol has the potential to replace existing fossil fuel usage without much modification in existing facilities. Bioethanol which generally produced from fermentation route produces low ethanol concentration. However, fuel grade ethanol requires low water content to avoid engine stall. Dehydration process has been increasingly important in fuel grade ethanol production. Among all dehydration processes, pervaporation is considered as the most promising technology. Zeolite possesses high potential in pervaporation of bioethanol into fuel grade ethanol. Zeolite membrane can either remove organic (ethanol) from aqueous mixture or water from the mixture, depending on the framework used. Hydrophilic zeolite membrane, e.g. LTA, can easily remove water from the mixture leaving high ethanol concentration. On the other hand, hydrophobic zeolite membrane, e.g. silicate-1, can remove ethanol from aqueous solution. This review presents the concept of bioethanol dehydration using zeolite membrane. Special attention is given to the performance of selected pathway related to framework selection.

The Use of Fibrous, Supramolecular Membranes and Human Tubular Cells for Renal Epithelial Tissue Engineering : Towards a Suitable Membrane for a Bioartificial Kidney

NARCIS (Netherlands)

Dankers, Patricia Y. W.; Boomker, Jasper M.; Huizinga-van der Vlag, Ali; Smedts, Frank M. M.; Harmsen, Martin C.; van Luyn, Marja J. A.

2010-01-01

A bioartificial kidney, which is composed of a membrane cartridge with renal epithelial cells, can substitute important kidney functions in patients with renal failure. A particular challenge is the maintenance of monolayer integrity and specialized renal epithelial cell functions ex vivo. We

The use of fibrous, supramolecular membranes and human tubular cells for renal epithelial tissue engineering: towards a suitable membrane for a bioartificial kidney,

NARCIS (Netherlands)

Dankers, P.Y.W.; Boomker, J.M.; Huizinga-van der Vlag, A.; Smedts, F.M.M.; Harmsen, M.C.; Luyn, van M.J.A.

2010-01-01

A bioartificial kidney, which is composed of a membrane cartridge with renal epithelial cells, can substitute important kidney functions in patients with renal failure. A particular challenge is the maintenance of monolayer integrity and specialized renal epithelial cell functions ex vivo. We

Modulators of Stomatal Lineage Signal Transduction Alter Membrane Contact Sites and Reveal Specialization among ERECTA Kinases.

Science.gov (United States)

Ho, Chin-Min Kimmy; Paciorek, Tomasz; Abrash, Emily; Bergmann, Dominique C

2016-08-22

Signal transduction from a cell's surface to its interior requires dedicated signaling elements and a cellular environment conducive to signal propagation. Plant development, defense, and homeostasis rely on plasma membrane receptor-like kinases to perceive endogenous and environmental signals, but little is known about their immediate downstream targets and signaling modifiers. Using genetics, biochemistry, and live-cell imaging, we show that the VAP-RELATED SUPPRESSOR OF TMM (VST) family is required for ERECTA-mediated signaling in growth and cell-fate determination and reveal a role for ERECTA-LIKE2 in modulating signaling by its sister kinases. We show that VSTs are peripheral plasma membrane proteins that can form complexes with integral ER-membrane proteins, thereby potentially influencing the organization of the membrane milieu to promote efficient and differential signaling from the ERECTA-family members to their downstream intracellular targets. Copyright © 2016 Elsevier Inc. All rights reserved.

The Membrane Paradigm and black-hole thermodynamics

International Nuclear Information System (INIS)

Thorne, K.S.

1986-01-01

A brief overview is given of the theoretical underpinnings of the Membrane Paradigm for black-hole physics. Then those underpinnings are used to elucidate the Paradigm's view that the laws of black-hole thermodynamics (including the statistical origin of black-hole entropy) are just a special case of the laws of thermodynamics for an ordinary, rotating, thermal reservoir

Superhydrophilic graphene oxide@electrospun cellulose nanofiber hybrid membrane for high-efficiency oil/water separation.

Science.gov (United States)

Ao, Chenghong; Yuan, Wei; Zhao, Jiangqi; He, Xu; Zhang, Xiaofang; Li, Qingye; Xia, Tian; Zhang, Wei; Lu, Canhui

2017-11-01

Inspired from fishscales, membranes with special surface wettability have been applied widely for the treatment of oily waste water. Herein, a novel superhydrophilic graphene oxide (GO)@electrospun cellulose nanofiber (CNF) membrane was successfully fabricated. This membrane exhibited a high separation efficiency, excellent antifouling properties, as well as a high flux for the gravity-driven oil/water separation. Moreover, the GO@CNF membrane was capable to effectively separate oil/water mixtures in a broad pH range or with a high concentration of salt, suggesting that this membrane was quite promising for future real-world practice in oil spill cleanup and oily wastewater treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Geomembrane special study

International Nuclear Information System (INIS)

1988-07-01

The objective of the Geomembrane Special Study was to asses the suitability of geomembranes in Uranium Mill Tailings Remedial Action (UMTRA) Project pile designs. Geomembranes, also called flexible membrane liners, are made of polymer resins and are thermoplastic materials. Part of the special study was to evaluate regulatory compliance and acceptability issues. This study was proposed because of the extensive use of geomembranes in hazardous waste site remedial actions and their accepted use in Resource Conservation and Recovery Act (RCRA) cells as both covers and liners to limit infiltration, or as part of leachate collection systems. This study has reviewed the recent geomembrane literature focusing on: (1) longevity; (2) performance; (3) constructibility; and (4) quality control/quality assurance considerations. In addition to these technical considerations, regulatory compliance and acceptability concerns were also evaluated. This report describes the results of the literature review, including correspondence with manufacturers, resin producers, experts in the field, and long-term major users. 12 refs., 2 tabs

Lipid rafts in epithelial brush borders: atypical membrane microdomains with specialized functions

DEFF Research Database (Denmark)

Danielsen, E Michael; Hansen, Gert H

2003-01-01

of the apical surface sterically accessible for membrane fusion/budding events. Many of these invaginations appear as pleiomorphic, deep apical tubules that extend up to 0.5-1 microm into the underlying terminal web region. Their sensitivity to methyl-beta-cyclodextrin suggests them to contain cholesterol...

The structure of the COPII transport-vesicle coat assembled on membranes.

Science.gov (United States)

Zanetti, Giulia; Prinz, Simone; Daum, Sebastian; Meister, Annette; Schekman, Randy; Bacia, Kirsten; Briggs, John A G

2013-09-17

Coat protein complex II (COPII) mediates formation of the membrane vesicles that export newly synthesised proteins from the endoplasmic reticulum. The inner COPII proteins bind to cargo and membrane, linking them to the outer COPII components that form a cage around the vesicle. Regulated flexibility in coat architecture is essential for transport of a variety of differently sized cargoes, but structural data on the assembled coat has not been available. We have used cryo-electron tomography and subtomogram averaging to determine the structure of the complete, membrane-assembled COPII coat. We describe a novel arrangement of the outer coat and find that the inner coat can assemble into regular lattices. The data reveal how coat subunits interact with one another and with the membrane, suggesting how coordinated assembly of inner and outer coats can mediate and regulate packaging of vesicles ranging from small spheres to large tubular carriers. DOI:http://dx.doi.org/10.7554/eLife.00951.001.

Lipidomics in research on yeast membrane lipid homeostasis.

Science.gov (United States)

de Kroon, Anton I P M

2017-08-01

Mass spectrometry is increasingly used in research on membrane lipid homeostasis, both in analyses of the steady state lipidome at the level of molecular lipid species, and in pulse-chase approaches employing stable isotope-labeled lipid precursors addressing the dynamics of lipid metabolism. Here my experience with, and view on mass spectrometry-based lipid analysis is presented, with emphasis on aspects of quantification of membrane lipid composition of the yeast Saccharomyces cerevisiae. This article is part of a Special Issue entitled: BBALIP_Lipidomics Opinion Articles edited by Sepp Kohlwein. Copyright © 2017 Elsevier B.V. All rights reserved.

Theoretical investigation of the sound attenuation of membrane-type acoustic metamaterials

International Nuclear Information System (INIS)

Zhang, Yuguang; Wen, Jihong; Xiao, Yong; Wen, Xisen; Wang, Jianwei

2012-01-01

Membrane-type acoustic metamaterials have been recently shown to exhibit good performance of sound attenuation in a low frequency range. An analytical approach for the fast calculation of sound transmission loss of the membrane-type acoustic metamaterials is presented here. The discussion indicate that the first transmission loss valley and the transmission loss peak depend strongly on the attaching mass, while the second transmission loss valley is mainly influenced by the membrane properties. The effects of membrane tension and mass position on the transmission loss and characteristic frequencies are also discussed in detail. -- Highlights: ► An analytical approach was presented here. ► First TL valley and peak depend strongly on attaching mass. ► Second TL valley is mainly influenced by properties of membrane. ► TL peak move to low frequency at a special position keeping TL valley motionless.

Ice formation in model biological membranes in the presence of cryoprotectors

Energy Technology Data Exchange (ETDEWEB)

Kiselev, M.A. E-mail: kiselev@nf.jinr.ru; Lesieur, P.; Kisselev, A.M.; Ollivon, M

2000-06-21

Ice formation in model biological membranes is studied by SAXS and WAXS in the presence of cryoprotectors: dimethyl sulfoxide and glycerol. Three types of phospholipid membranes: DPPC, DMPC, DSPC are chosen for the investigation as well-studied model biological membranes. A special cryostat is used for sample cooling from 14.1 deg. C to -55.4 deg. C. The ice formation is detected only by WAXS in binary phospholipid/water and ternary phospholipid/cryoprotector/water systems in the condition of excess solvent. Ice formation in a binary phospholipid/water system creates an abrupt decrease of the membrane repeat distance by {delta}d, the so-called ice-induced dehydration of intermembrane space. The value of {delta}d decreases as the cryoprotector concentration increases. The formation of ice does not influence the membrane structure ({delta}d=0) for cryoprotector mole fractions higher than 0.05.

Potassium accumulation by the glial membrane pump as revealed by membrane potential recording from isolated rabbit retinal Müller cells.

Science.gov (United States)

Reichenbach, A; Nilius, B; Eberhardt, W

1986-01-30

Müller (glial) cells were isolated from rabbit retinae by papaine and mechanical dissociation. In a special perfusion chamber, the cells were penetrated with a recording electrode. When high-K+ solutions were applied into the environment of the cells by means of a second micropipette, the cell membrane depolarized strongly. During prolonged application of high-K+ solutions, however, there occurred a marked repolarization, and after cessation of high-K+ application, a strong hyperpolarization was observed. Both effects disappeared under the influence of ouabain, suggesting the accumulation of intracellular K+ by an active membrane pump. The data were used for calculation of the membrane's Na+:K+ permeability ratio, the intracellular K+ concentration, the pump rate and the mean pump site density. The calculated values are in good agreement with published data from mammalian astrocytes and are compared with those from amphibian Müller cells.

Structure and Dynamic Properties of Membrane Proteins using NMR

DEFF Research Database (Denmark)

Rösner, Heike; Kragelund, Birthe

2012-01-01

conformational changes. Their structural and functional decoding is challenging and has imposed demanding experimental development. Solution nuclear magnetic resonance (NMR) spectroscopy is one of the techniques providing the capacity to make a significant difference in the deciphering of the membrane protein...... structure-function paradigm. The method has evolved dramatically during the last decade resulting in a plethora of new experiments leading to a significant increase in the scientific repertoire for studying membrane proteins. Besides solving the three-dimensional structures using state-of-the-art approaches......-populated states, this review seeks to introduce the vast possibilities solution NMR can offer to the study of membrane protein structure-function analyses with special focus on applicability. © 2012 American Physiological Society. Compr Physiol 2:1491-1539, 2012....

Stimulating the development of coordination in pupils with developmental difficulties in elementary school

Directory of Open Access Journals (Sweden)

Maksimović Jasna

2015-01-01

Full Text Available The paper deals with the effects of specially programmed types of physical activities on the development of coordination of the pupils with developmental difficulties in regular elementary schools. The method of pedagogical research with parallel groups was used in the research which included 135 junior elementary-school pupils. Among them 90 pupils had one of developmental difficulties (intellectual disability, visual and hearing disturbances and they were divided into an experimental and a control group 1, while other pupils had typical development and they formed the control group 2 (n=45. Besides regular classes of physical education the experimental group was engaged in a special programme, devised and implemented into the Individual Educational Plan, as one of the types of intervention within the system of inclusive education. The research lasted for three months during which the groups were tested by the tests of coordination and the data obtained at the beginning and the end of the research period were processed by the application of univariant analysis of covariance and the T-test of the paired samples. The results show that the pupils with developmental difficulties can considerably progress in the development of coordination if their individual characteristics are recognized and optimal conditions are provided.

Double anisotropic electrically conductive flexible Janus-typed membranes.

Science.gov (United States)

Li, Xiaobing; Ma, Qianli; Tian, Jiao; Xi, Xue; Li, Dan; Dong, Xiangting; Yu, Wensheng; Wang, Xinlu; Wang, Jinxian; Liu, Guixia

2017-12-07

Novel type III anisotropic conductive films (ACFs), namely flexible Janus-typed membranes, were proposed, designed and fabricated for the first time. Flexible Janus-typed membranes composed of ordered Janus nanobelts were constructed by electrospinning, which simultaneously possess fluorescence and double electrically conductive anisotropy. For the fabrication of the Janus-typed membrane, Janus nanobelts comprising a conductive side and an insulative-fluorescent side were primarily fabricated, and then the Janus nanobelts are arranged into parallel arrays using an aluminum rotary drum as the collector to obtain a single anisotropically conductive film. Subsequently, a secondary electrospinning process was applied to the as-prepared single anisotropically conductive films to acquire the final Janus-typed membrane. For this Janus-typed membrane, namely its left-to-right structure, anisotropic electrical conduction synchronously exists on both sides, and furthermore, the two electrically conductive directions are perpendicular. By modulating the amount of Eu(BA) 3 phen complex and conducting polyaniline (PANI), the characteristics and intensity of the fluorescence-electricity dual-function in the membrane can be tuned. The high integration of this peculiar Janus-typed membrane with simultaneous double electrically conductive anisotropy-fluorescent dual-functionality is successfully realized in this study. This design philosophy and preparative technique will provide support for the design and construction of new types of special nanostructures with multi-functionality.

A new look at lipid-membrane structure in relation to drug research

DEFF Research Database (Denmark)

Mouritsen, Ole G.; Jørgensen, Kent

1998-01-01

Lipid-bilayer membranes are key objects in drug research in relation to (i) interaction of drugs with membrane-bound receptors, (ii) drug targeting, penetration, and permeation of cell membranes, and (iii) use of liposomes in micro-encapsulation technologies for drug delivery. Rational design...... of new drugs and drug-delivery systems therefore requries insight into the physical properties of lipid-bilayer membranes. This mini-review provides a perspective on the current view of lipid-bilayer structure and dynamics based on information obtained from a variety of recent experimental...... and theoretical studies. Special attention is paid to trans-bilayer structure, lateral molecular organization of the lipid bilayer, lipid-mediated protein assembly, and lipid-bilayer permeability. It is argued that lipids play a major role in lipid membrane-organization and functionality....

(CryoTransmission Electron Microscopy of Phospholipid Model Membranes Interacting with Amphiphilic and Polyphilic Molecules

Directory of Open Access Journals (Sweden)

Annette Meister

2017-10-01

Full Text Available Lipid membranes can incorporate amphiphilic or polyphilic molecules leading to specific functionalities and to adaptable properties of the lipid bilayer host. The insertion of guest molecules into membranes frequently induces changes in the shape of the lipid matrix that can be visualized by transmission electron microscopy (TEM techniques. Here, we review the use of stained and vitrified specimens in (cryoTEM to characterize the morphology of amphiphilic and polyphilic molecules upon insertion into phospholipid model membranes. Special emphasis is placed on the impact of novel synthetic amphiphilic and polyphilic bolalipids and polymers on membrane integrity and shape stability.

Numerical tension adjustment of x-ray membrane to represent goat skin kompang

Science.gov (United States)

Siswanto, Waluyo Adi; Abdullah, Muhammad Syiddiq Bin

2017-04-01

This paper presents a numerical membrane model of traditional musical instrument kompang that will be used to find the parameter of membrane tension of x-ray membrane representing the classical goat-skin membrane of kompang. In this study, the experiment towards the kompang is first conducted in an acoustical anechoic enclosure and in parallel a mathematical model of the kompang membrane is developed to simulate the vibration of the kompang membrane in polar coordinate by implementing Fourier-Bessel wave function. The wave equation in polar direction in mode 0,1 is applied to provide the corresponding natural frequencies of the circular membrane. The value of initial and boundary conditions in the function is determined from experiment to allow the correct development of numerical equation. The numerical mathematical model is coded in SMath for the accurate numerical analysis as well as the plotting tool. Two kompang membrane cases with different membrane materials, i.e. goat skin and x-ray film membranes with fixed radius of 0.1 m are used in the experiment. An alternative of kompang's membrane made of x-ray film with the appropriate tension setting can be used to represent the sound of traditional goat-skin kompang. The tension setting of the membrane to resemble the goat-skin is 24N. An effective numerical tool has been develop to help kompang maker to set the tension of x-ray membrane. In the future application, any tradional kompang with different size can be replaced by another membrane material if the tension is set to the correct tension value. The developed numerical tool is useful and handy to calculate the tension of the alternative membrane material.

Periplasmic quality control in biogenesis of outer membrane proteins.

Science.gov (United States)

Lyu, Zhi Xin; Zhao, Xin Sheng

2015-04-01

The β-barrel outer membrane proteins (OMPs) are integral membrane proteins that reside in the outer membrane of Gram-negative bacteria and perform a diverse range of biological functions. Synthesized in the cytoplasm, OMPs must be transported across the inner membrane and through the periplasmic space before they are assembled in the outer membrane. In Escherichia coli, Skp, SurA and DegP are the most prominent factors identified to guide OMPs across the periplasm and to play the role of quality control. Although extensive genetic and biochemical analyses have revealed many basic functions of these periplasmic proteins, the mechanism of their collaboration in assisting the folding and insertion of OMPs is much less understood. Recently, biophysical approaches have shed light on the identification of the intricate network. In the present review, we summarize recent advances in the characterization of these key factors, with a special emphasis on the multifunctional protein DegP. In addition, we present our proposed model on the periplasmic quality control in biogenesis of OMPs.

Co-ordinated voltage control of DFIG wind turbines in uninterrupted operation during grid faults

DEFF Research Database (Denmark)

Hansen, Anca Daniela; Michalke, G.; Sørensen, Poul Ejnar

2007-01-01

Emphasis in this article is on the design of a co-ordinated voltage control strategy for doubly fed induction generator (DFIG) wind turbines that enhances their capability to provide grid support during grid faults. In contrast to its very good performance in normal operation, the DFIG wind turbine...... concept is quite sensitive to grid faults and requires special power converter protection. The fault ride-through and grid support capabilities of the DFIG address therefore primarily the design of DFIG wind turbine control with special focus on power converter protection and voltage control issues....... A voltage control strategy is designed and implemented in this article, based on the idea that both converters of the DFIG (i.e. rotor-side converter and grid-side converter) participate in the grid voltage control in a co-ordinated manner. By default the grid voltage is controlled by the rotor...

Accuracy increase of the coordinate measurement based on the model production of geometrical parts specifications

Science.gov (United States)

Zlatkina, O. Yu

2018-04-01

There is a relationship between the service properties of component parts and their geometry; therefore, to predict and control the operational characteristics of parts and machines, it is necessary to measure their geometrical specifications. In modern production, a coordinate measuring machine is the advanced measuring instrument of the products geometrical specifications. The analysis of publications has shown that during the coordinate measurements the problems of choosing locating chart of parts and coordination have not been sufficiently studied. A special role in the coordination of the part is played by the coordinate axes informational content. Informational content is the sum of the degrees of freedom limited by the elementary item of a part. The coordinate planes of a rectangular coordinate system have different informational content (three, two, and one). The coordinate axes have informational content of four, two and zero. The higher the informational content of the coordinate plane or axis, the higher its priority for reading angular and linear coordinates is. The geometrical model production of the coordinate measurements object taking into account the information content of coordinate planes and coordinate axes allows us to clearly reveal the interrelationship of the coordinates of the deviations in location, sizes and deviations of their surfaces shape. The geometrical model helps to select the optimal locating chart of parts for bringing the machine coordinate system to the part coordinate system. The article presents an algorithm the model production of geometrical specifications using the example of the piston rod of a compressor.

Step-by-step seeding procedure for preparing HKUST-1 membrane on porous α-alumina support.

Science.gov (United States)

Nan, Jiangpu; Dong, Xueliang; Wang, Wenjin; Jin, Wanqin; Xu, Nanping

2011-04-19

Metal-organic framework (MOF) membranes have attracted considerable attention because of their striking advantages in small-molecule separation. The preparation of an integrated MOF membrane is still a major challenge. Depositing a uniform seed layer on a support for secondary growth is a main route to obtaining an integrated MOF membrane. A novel seeding method to prepare HKUST-1 (known as Cu(3)(btc)(2)) membranes on porous α-alumina supports is reported. The in situ production of the seed layer was realized in step-by-step fashion via the coordination of H(3)btc and Cu(2+) on an α-alumina support. The formation process of the seed layer was observed by ultraviolet-visible absorption spectroscopy and atomic force microscopy. An integrated HKUST-1 membrane could be synthesized by the secondary hydrothermal growth on the seeded support. The gas permeation performance of the membrane was evaluated. © 2011 American Chemical Society

Membrane Modeling, Simulation and Optimization for Propylene/Propane Separation

KAUST Repository

Alshehri, Ali

2015-06-01

Energy efficiency is critical for sustainable industrial growth and the reduction of environmental impacts. Energy consumption by the industrial sector accounts for more than half of the total global energy usage and, therefore, greater attention is focused on enhancing this sector’s energy efficiency. It is predicted that by 2020, more than 20% of today’s energy consumption can be avoided in countries that have effectively implemented an action plan towards efficient energy utilization. Breakthroughs in material synthesis of high selective membranes have enabled the technology to be more energy efficient. Hence, high selective membranes are increasingly replacing conventional energy intensive separation processes, such as distillation and adsorption units. Moreover, the technology offers more special features (which are essential for special applications) and its small footprint makes membrane technology suitable for platform operations (e.g., nitrogen enrichment for oil and gas offshore sites). In addition, its low maintenance characteristics allow the technology to be applied to remote operations. For these reasons, amongst other, the membrane technology market is forecast to reach $16 billion by 2017. This thesis is concerned with the engineering aspects of membrane technology and covers modeling, simulation and optimization of membranes as a stand-alone process or as a unit operation within a hybrid system. Incorporating the membrane model into a process modeling software simplifies the simulation and optimization of the different membrane processes and hybrid configurations, since all other unit operations are pre-configured. Various parametric analyses demonstrated that only the membrane selectivity and transmembrane pressure ratio parameters define a membrane’s ability to accomplish a certain separation task. Moreover, it was found that both membrane selectivity and pressure ratio exhibit a minimum value that is only defined by the feed composition

Emerging insights into the roles of membrane tethers from analysis of whole organisms: The tip of an iceberg?

Directory of Open Access Journals (Sweden)

Wei Hong eToh

2016-02-01

Full Text Available Membrane tethers have been identified throughout different compartments of the endomembrane system. It is now well established that a number of membrane tethers mediate docking of membrane carriers in anterograde and retrograde transport and in regulating the organization of membrane compartments. Much of our information on membrane tethers have been obtained from the analysis of individual membrane tethers in cultured cells. In the future it will be important to better appreciate the network of interactions mediated by tethers and the potential co-ordination of their collective functions in vivo. There are now a number of studies which have analyzed membrane tethers in tissues and organisms which are providing new insights into the role of this class of membrane protein at the physiological level. Here we review recent advances in the understanding of the function of membrane tethers from knock outs (or knock downs in whole organisms and from mutations in tethers associated with disease.

Test theories of special relativity: a general critique

International Nuclear Information System (INIS)

Maciel, A.K.A.; Tiomno, J.

1988-01-01

Absolute Spacetime Theories conceived for the purpose of testing Special Relativity (SR) are reviewed. It is found that most theories proposed were in fact SR in different coordinate systems, since in general no specific SR violations were introduced. Models based on possible SR violating mechanisms are considered. Misconceptions in recently published papers are examined. (author) [pt

Recommendations for Optimizing Internal Management Mechanism of Farmers’ Specialized Cooperatives

Institute of Scientific and Technical Information of China (English)

Jingxiao; CHEN

2016-01-01

Based on the survey of 38 farmers’ specialized cooperatives in Hubei Province,this paper analyzed existing problems in internal management mechanism of cooperatives,including widespread problem of centralized control,imperfect supervision mechanism,lack of effective incentive mechanism,insufficient specialized personnel,and limited participation of cooperative members in management. It elaborated causes for these problems from the perspective of practice. Finally,it came up with recommendations for optimizing farmers’ specialized cooperatives: building democratic decision making mechanism with coordination of cooperative members and able personnel,establishing supervision mechanism suitable for self demands,improving internal incentive mechanism,establishing talent introduction and cultivation mechanism in proper time,and strengthening internal member management of cooperatives.

Coordinating a Supply Chain with a Loss-Averse Retailer and Effort Dependent Demand

Science.gov (United States)

Li, Liying

2014-01-01

This study investigates the channel coordination issue of a supply chain with a risk-neutral manufacturer and a loss-averse retailer facing stochastic demand that is sensitive to sales effort. Under the loss-averse newsvendor setting, a distribution-free gain/loss-sharing-and-buyback (GLB) contract has been shown to be able to coordinate the supply chain. However, we find that a GLB contract remains ineffective in managing the supply chain when retailer sales efforts influence the demand. To effectively coordinate the channel, we propose to combine a GLB contract with sales rebate and penalty (SRP) contract. In addition, we discover a special class of gain/loss contracts that can coordinate the supply chain and arbitrarily allocate the expected supply chain profit between the manufacturer and the retailer. We then analyze the effect of loss aversion on the retailer's decision-making behavior and supply chain performance. Finally, we perform a numerical study to illustrate the findings and gain additional insights. PMID:25197696

Coordinating a supply chain with a loss-averse retailer and effort dependent demand.

Science.gov (United States)

Li, Liying; Wang, Yong

2014-01-01

This study investigates the channel coordination issue of a supply chain with a risk-neutral manufacturer and a loss-averse retailer facing stochastic demand that is sensitive to sales effort. Under the loss-averse newsvendor setting, a distribution-free gain/loss-sharing-and-buyback (GLB) contract has been shown to be able to coordinate the supply chain. However, we find that a GLB contract remains ineffective in managing the supply chain when retailer sales efforts influence the demand. To effectively coordinate the channel, we propose to combine a GLB contract with sales rebate and penalty (SRP) contract. In addition, we discover a special class of gain/loss contracts that can coordinate the supply chain and arbitrarily allocate the expected supply chain profit between the manufacturer and the retailer. We then analyze the effect of loss aversion on the retailer's decision-making behavior and supply chain performance. Finally, we perform a numerical study to illustrate the findings and gain additional insights.

Christoffel symbols and inertia in flat space-time theory. [Curvilinear coordinate systems

Energy Technology Data Exchange (ETDEWEB)

Krause, J [Universidad Central de Venezuela, Caracas

1976-11-01

A necessary and sufficient criterion of inertia is presented, for the flat space-time theory of general frames of reference, in terms of the vanishing of some typical components of the affine connection pertaining to curvilinear coordinate systems. The physical identification of inertial forces thus arises in the context of the special theory of relativity.

It's My Life! Career Paths for Young Women in Transition. Coordinator's Handbook.

Science.gov (United States)

Florio, Carol; And Others

This document is the coordinator's handbook for a four-day workshop for young women in transition from high school to two-year colleges. The program covers career information, self-awareness and skills assessment (with special regard for mathematics), the many roles of women, and decision making and planning. It includes large- and small-group…

A model for the biosynthesis and transport of plasma membrane-associated signaling receptors to the cell surface

Directory of Open Access Journals (Sweden)

Sorina Claudia Popescu

2012-04-01

Full Text Available Intracellular protein transport is emerging as critical in determining the outcome of receptor-activated signal transduction pathways. In plants, relatively little is known about the nature of the molecular components and mechanisms involved in coordinating receptor synthesis and transport to the cell surface. Recent advances in this field indicate that signaling pathways and intracellular transport machinery converge and coordinate to render receptors competent for signaling at their plasma membrane activity sites. The biogenesis and transport to the cell surface of signaling receptors appears to require both general trafficking and receptor-specific factors. Several molecular determinants, residing or associated with compartments of the secretory pathway and known to influence aspects in receptor biogenesis, are discussed and integrated into a predictive cooperative model for the functional expression of signaling receptors at the plasma membrane.

Separation of variables for the nonlinear wave equation in polar coordinates

International Nuclear Information System (INIS)

Shermenev, Alexander

2004-01-01

Some classical types of nonlinear wave motion in polar coordinates are studied within quadratic approximation. When the nonlinear quadratic terms in the wave equation are arbitrary, the usual perturbation techniques used in polar coordinates leads to overdetermined systems of linear algebraic equations for the unknown coefficients. However, we show that these overdetermined systems are compatible with the special case of the nonlinear shallow water equation and express explicitly the coefficients of the first two harmonics as polynomials of the Bessel functions of radius and of the trigonometric functions of angle. It gives a series of solutions to the nonlinear shallow water equation that are periodic in time and found with the same accuracy as the equation is derived

How students learn to coordinate knowledge of physical and mathematical models in cellular physiology

Science.gov (United States)

Lira, Matthew

This dissertation explores the Knowledge in Pieces (KiP) theory to account for how students learn to coordinate knowledge of mathematical and physical models in biology education. The KiP approach characterizes student knowledge as a fragmented collection of knowledge elements as opposed to stable and theory-like knowledge. This dissertation sought to use this theoretical lens to account for how students understand and learn with mathematical models and representations, such as equations. Cellular physiology provides a quantified discipline that leverages concepts from mathematics, physics, and chemistry to understand cellular functioning. Therefore, this discipline provides an exemplary context for assessing how biology students think and learn with mathematical models. In particular, the resting membrane potential provides an exemplary concept well defined by models of dynamic equilibrium borrowed from physics and chemistry. In brief, membrane potentials, or voltages, "rest" when the electrical and chemical driving forces for permeable ionic species are equal in magnitude but opposite in direction. To assess students' understandings of this concept, this dissertation employed three studies: the first study employed the cognitive clinical interview to assess student thinking in the absence and presence of equations. The second study employed an intervention to assess student learning and the affordances of an innovative assessment. The third student employed a human-computer-interaction paradigm to assess how students learn with a novel multi-representational technology. Study 1 revealed that students saw only one influence--the chemical gradient--and that students coordinated knowledge of only this gradient with the related equations. Study 2 revealed that students benefited from learning with the multi-representational technology and that the assessment detected performance gains across both calculation and explanation tasks. Last, Study 3 revealed how students

On the use of supported ceria membranes for oxyfuel process/syngas production

DEFF Research Database (Denmark)

Lobera, M.P.; Serra, J.M.; Foghmoes, Søren Preben Vagn

2011-01-01

Ceramic oxygen transport membranes (OTMs) enable selective oxygen separation from air at high temperatures. Among several potential applications for OTMs, the use in (1) oxygen production for oxyfuel power plants and (2) the integration in high-temperature catalytic membrane reactors for alkane...... upgrading through selective oxidative reactions are of special interest. Nevertheless, these applications involve the direct contact of the membrane surface with carbon-rich atmospheres. Most state-of-the-art permeable membranes are based on perovskites, which are prone to carbonation under operation in CO2......-rich environments and/or decomposition in reducing gas environments. The oxygen flux through supported thin film membranes of Ce0.9Gd0.1O1.95−δ (CGO) with 2 mol.% of cobalt was measured for oxygen separation in oxyfuel processes and in syngas production and degradation was compared to perovskite...

Special relativity

International Nuclear Information System (INIS)

French, A.P.

1982-01-01

This book is an introduction to special relativity theory. After a discussion of the limits of Newton's mechanics and the pecularities in the propagation of light the Lorentz transformation is introduced. Then the measurement of space and time intervals in the framework of relativity theory is considered. Thereafter the addition of velocities and acceleration are considered in this framework. Then relativistic kinematics of particle interactions are described. Then the four-dimensional calculus in space-time coordinates is introduced. Finally an introduction is given to the treatment of the electromagnetic field in the framework of relativity theory. Every chapter contains exercise problems with solutions. This book is suited for all students who want to get some fundamental knowledge about relativity theory. (HSI) [de

Poisson Coordinates.

Science.gov (United States)

Li, Xian-Ying; Hu, Shi-Min

2013-02-01

Harmonic functions are the critical points of a Dirichlet energy functional, the linear projections of conformal maps. They play an important role in computer graphics, particularly for gradient-domain image processing and shape-preserving geometric computation. We propose Poisson coordinates, a novel transfinite interpolation scheme based on the Poisson integral formula, as a rapid way to estimate a harmonic function on a certain domain with desired boundary values. Poisson coordinates are an extension of the Mean Value coordinates (MVCs) which inherit their linear precision, smoothness, and kernel positivity. We give explicit formulas for Poisson coordinates in both continuous and 2D discrete forms. Superior to MVCs, Poisson coordinates are proved to be pseudoharmonic (i.e., they reproduce harmonic functions on n-dimensional balls). Our experimental results show that Poisson coordinates have lower Dirichlet energies than MVCs on a number of typical 2D domains (particularly convex domains). As well as presenting a formula, our approach provides useful insights for further studies on coordinates-based interpolation and fast estimation of harmonic functions.

Development of modifications to the material point method for the simulation of thin membranes, compressible fluids, and their interactions

Energy Technology Data Exchange (ETDEWEB)

York, A.R. II [Sandia National Labs., Albuquerque, NM (United States). Engineering and Process Dept.

1997-07-01

The material point method (MPM) is an evolution of the particle in cell method where Lagrangian particles or material points are used to discretize the volume of a material. The particles carry properties such as mass, velocity, stress, and strain and move through a Eulerian or spatial mesh. The momentum equation is solved on the Eulerian mesh. Modifications to the material point method are developed that allow the simulation of thin membranes, compressible fluids, and their dynamic interactions. A single layer of material points through the thickness is used to represent a membrane. The constitutive equation for the membrane is applied in the local coordinate system of each material point. Validation problems are presented and numerical convergence is demonstrated. Fluid simulation is achieved by implementing a constitutive equation for a compressible, viscous, Newtonian fluid and by solution of the energy equation. The fluid formulation is validated by simulating a traveling shock wave in a compressible fluid. Interactions of the fluid and membrane are handled naturally with the method. The fluid and membrane communicate through the Eulerian grid on which forces are calculated due to the fluid and membrane stress states. Validation problems include simulating a projectile impacting an inflated airbag. In some impact simulations with the MPM, bodies may tend to stick together when separating. Several algorithms are proposed and tested that allow bodies to separate from each other after impact. In addition, several methods are investigated to determine the local coordinate system of a membrane material point without relying upon connectivity data.

Unique battery with an active membrane separator having uniform physico-chemically functionalized ion channels and a method making the same

Science.gov (United States)

Gerald, II, Rex E.; Ruscic, Katarina J [Chicago, IL; Sears, Devin N [Spruce Grove, CA; Smith, Luis J [Natick, MA; Klingler, Robert J [Glenview, IL; Rathke, Jerome W [Homer Glen, IL

2012-02-21

The invention relates to a unique battery having an active, porous membrane and method of making the same. More specifically the invention relates to a sealed battery system having a porous, metal oxide membrane with uniform, physicochemically functionalized ion channels capable of adjustable ionic interaction. The physicochemically-active porous membrane purports dual functions: an electronic insulator (separator) and a unidirectional ion-transporter (electrolyte). The electrochemical cell membrane is activated for the transport of ions by contiguous ion coordination sites on the interior two-dimensional surfaces of the trans-membrane unidirectional pores. The membrane material is designed to have physicochemical interaction with ions. Control of the extent of the interactions between the ions and the interior pore walls of the membrane and other materials, chemicals, or structures contained within the pores provides adjustability of the ionic conductivity of the membrane.

Hybrid flotation--membrane filtration process for the removal of heavy metal ions from wastewater.

Science.gov (United States)

Blöcher, C; Dorda, J; Mavrov, V; Chmiel, H; Lazaridis, N K; Matis, K A

2003-09-01

A promising process for the removal of heavy metal ions from aqueous solutions involves bonding the metals firstly to a special bonding agent and then separating the loaded bonding agents from the wastewater stream by separation processes. For the separation stage, a new hybrid process of flotation and membrane separation has been developed in this work by integrating specially designed submerged microfiltration modules directly into a flotation reactor. This made it possible to combine the advantages of both flotation and membrane separation while overcoming the limitations. The feasibility of this hybrid process was proven using powdered synthetic zeolites as bonding agents. Stable fluxes of up to 80l m(-2)h(-1) were achieved with the ceramic flat-sheet multi-channel membranes applied at low transmembrane pressure (copper, nickel and zinc, were reduced from initial concentrations of 474, 3.3 and 167mg x l(-1), respectively, to below 0.05 mg x l(-1), consistently meeting the discharge limits.

Electric field-induced reorganization of two-component supported bilayer membranes.

Science.gov (United States)

Groves, J T; Boxer, S G; McConnell, H M

1997-12-09

Application of electric fields tangent to the plane of a confined patch of fluid bilayer membrane can create lateral concentration gradients of the lipids. A thermodynamic model of this steady-state behavior is developed for binary systems and tested with experiments in supported lipid bilayers. The model uses Flory's approximation for the entropy of mixing and allows for effects arising when the components have different molecular areas. In the special case of equal area molecules the concentration gradient reduces to a Fermi-Dirac distribution. The theory is extended to include effects from charged molecules in the membrane. Calculations show that surface charge on the supporting substrate substantially screens electrostatic interactions within the membrane. It also is shown that concentration profiles can be affected by other intermolecular interactions such as clustering. Qualitative agreement with this prediction is provided by comparing phosphatidylserine- and cardiolipin-containing membranes.

Direct Cytoskeleton Forces Cause Membrane Softening in Red Blood Cells

Science.gov (United States)

Rodríguez-García, Ruddi; López-Montero, Iván; Mell, Michael; Egea, Gustavo; Gov, Nir S.; Monroy, Francisco

2015-01-01

Erythrocytes are flexible cells specialized in the systemic transport of oxygen in vertebrates. This physiological function is connected to their outstanding ability to deform in passing through narrow capillaries. In recent years, there has been an influx of experimental evidence of enhanced cell-shape fluctuations related to metabolically driven activity of the erythroid membrane skeleton. However, no direct observation of the active cytoskeleton forces has yet been reported to our knowledge. Here, we show experimental evidence of the presence of temporally correlated forces superposed over the thermal fluctuations of the erythrocyte membrane. These forces are ATP-dependent and drive enhanced flickering motions in human erythrocytes. Theoretical analyses provide support for a direct force exerted on the membrane by the cytoskeleton nodes as pulses of well-defined average duration. In addition, such metabolically regulated active forces cause global membrane softening, a mechanical attribute related to the functional erythroid deformability. PMID:26083919

Bound-Preserving Discontinuous Galerkin Methods for Conservative Phase Space Advection in Curvilinear Coordinates

Energy Technology Data Exchange (ETDEWEB)

Mezzacappa, Anthony [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Endeve, Eirik [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hauck, Cory D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Xing, Yulong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-02-01

We extend the positivity-preserving method of Zhang & Shu [49] to simulate the advection of neutral particles in phase space using curvilinear coordinates. The ability to utilize these coordinates is important for non-equilibrium transport problems in general relativity and also in science and engineering applications with specific geometries. The method achieves high-order accuracy using Discontinuous Galerkin (DG) discretization of phase space and strong stabilitypreserving, Runge-Kutta (SSP-RK) time integration. Special care in taken to ensure that the method preserves strict bounds for the phase space distribution function f; i.e., f ϵ [0, 1]. The combination of suitable CFL conditions and the use of the high-order limiter proposed in [49] is su cient to ensure positivity of the distribution function. However, to ensure that the distribution function satisfies the upper bound, the discretization must, in addition, preserve the divergencefree property of the phase space ow. Proofs that highlight the necessary conditions are presented for general curvilinear coordinates, and the details of these conditions are worked out for some commonly used coordinate systems (i.e., spherical polar spatial coordinates in spherical symmetry and cylindrical spatial coordinates in axial symmetry, both with spherical momentum coordinates). Results from numerical experiments - including one example in spherical symmetry adopting the Schwarzschild metric - demonstrate that the method achieves high-order accuracy and that the distribution function satisfies the maximum principle.

Alteration of polyethersulphone membranes through UV-induced modification using various materials: A brief review

Directory of Open Access Journals (Sweden)

Law Yong Ng

2017-05-01

Full Text Available Polyethersulphone (PES membranes have been widely applied in various separation applications such as microfiltration, ultrafiltration and nanofiltration. This has occurred as these membranes are easy to form, have good mechanical strength and good chemical stability (resistant to acidic or alkaline conditions due to the presence of aromatic hydrocarbon groups in the structure. PES membranes are commonly fabricated through the phase inversion method due to the simplicity of the process. However, PES membranes are generally hydrophobic, which usually requires them to be modified before application. In most cases, these methods can reduce the hydrophobicity of the membrane surface and thus reduce membrane fouling during application. This review will further discuss the recently developed UV-induced modifications of PES membranes. The UV-induced grafting method is easy to apply to existing PES membranes, with or without the need for a photo-initiator. Additionally, nanoparticles entrapped in PES membranes subsequently exposed to UV-irradiation have been reported to possess photo-catalytic activity. However, UV-irradiation methods still require special care in order to produce membranes with the best performance.

Using membrane transporters to improve crops for sustainable food production

Science.gov (United States)

With the global population predicted to grow by at least 25% by 2050, the need for sustainable production of nutritious foods is critical for human and environmental well-being. Recent advances show that specialized plant membrane transporters can be utilized to enhance yields of staple crops, incre...

Evolutionary transformations of fetal membrane characters in Eutheria with special reference to Afrotheria

DEFF Research Database (Denmark)

Mess, Andrea; Carter, Anthony M.

2006-01-01

in traditional systematics. In the present study, we attempted a reconstruction of the evolution of characters associated with placentation, the fetal membranes and the female reproductive tract. The evolutionary history of 21 characters has been traced, based on a current hypothesis of eutherian relationships...

Ground-based observations coordinated with Viking satellite measurements

International Nuclear Information System (INIS)

Opgenoorth, H.J.; Kirkwood, S.

1989-01-01

The instrumentation and the orbit of the Viking satellite made this first Swedish satellite mission ideally suited for coordinated observations with the dense network of ground-based stations in northern Scandinavia. Several arrays of complementing instruments such as magnetometers, all-sky cameras, riometers and doppler radars monitored on a routine basis the ionosphere under the magnetospheric region passed by Viking. For a large number of orbits the Viking passages close to Scandinavia were covered by the operation of specially designed programmes at the European incoherent-scatter facility (EISCAT). First results of coordinated observations on the ground and aboard Viking have shed new light on the most spectacular feature of substorm expansion, the westward-travelling surge. The end of a substorm and the associated decay of a westward-travelling surge have been analysed. EISCAT measurements of high spatial and temporal resolution indicate that the conductivities and electric fields associated with westward-travelling surges are not represented correctly by the existing models. (author)

Microdomains in the membrane landscape shape antigen-presenting cell function.

Science.gov (United States)

Zuidscherwoude, Malou; de Winde, Charlotte M; Cambi, Alessandra; van Spriel, Annemiek B

2014-02-01

The plasma membrane of immune cells is a highly organized cell structure that is key to the initiation and regulation of innate and adaptive immune responses. It is well-established that immunoreceptors embedded in the plasma membrane have a nonrandom spatial distribution that is important for coupling to components of intracellular signaling cascades. In the last two decades, specialized membrane microdomains, including lipid rafts and TEMs, have been identified. These domains are preformed structures ("physical entities") that compartmentalize proteins, lipids, and signaling molecules into multimolecular assemblies. In APCs, different microdomains containing immunoreceptors (MHC proteins, PRRs, integrins, among others) have been reported that are imperative for efficient pathogen recognition, the formation of the immunological synapse, and subsequent T cell activation. In addition, recent work has demonstrated that tetraspanin microdomains and lipid rafts are involved in BCR signaling and B cell activation. Research into the molecular mechanisms underlying membrane domain formation is fundamental to a comprehensive understanding of membrane-proximal signaling and APC function. This review will also discuss the advances in the microscopy field for the visualization of the plasma membrane, as well as the recent progress in targeting microdomains as novel, therapeutic approach for infectious and malignant diseases.

IEP (Individualized Educational Program) Co-operation between Optimal Support of Students with Special Needs

Science.gov (United States)

Ogoshi, Yasuhiro; Nakai, Akio; Ogoshi, Sakiko; Mitsuhashi, Yoshinori; Araki, Chikahiro

A key aspect of the optimal support of students with special needs is co-ordination and co-operation between school, home and specialized agencies. Communication between these entities is of prime importance and can be facilitated through the use of a support system implementing ICF guidelines as outlined. This communication system can be considered to be a preventative rather than allopathic support.

Patient- and family-centered care coordination: a framework for integrating care for children and youth across multiple systems.

Science.gov (United States)

2014-05-01

Understanding a care coordination framework, its functions, and its effects on children and families is critical for patients and families themselves, as well as for pediatricians, pediatric medical subspecialists/surgical specialists, and anyone providing services to children and families. Care coordination is an essential element of a transformed American health care delivery system that emphasizes optimal quality and cost outcomes, addresses family-centered care, and calls for partnership across various settings and communities. High-quality, cost-effective health care requires that the delivery system include elements for the provision of services supporting the coordination of care across settings and professionals. This requirement of supporting coordination of care is generally true for health systems providing care for all children and youth but especially for those with special health care needs. At the foundation of an efficient and effective system of care delivery is the patient-/family-centered medical home. From its inception, the medical home has had care coordination as a core element. In general, optimal outcomes for children and youth, especially those with special health care needs, require interfacing among multiple care systems and individuals, including the following: medical, social, and behavioral professionals; the educational system; payers; medical equipment providers; home care agencies; advocacy groups; needed supportive therapies/services; and families. Coordination of care across settings permits an integration of services that is centered on the comprehensive needs of the patient and family, leading to decreased health care costs, reduction in fragmented care, and improvement in the patient/family experience of care. Copyright © 2014 by the American Academy of Pediatrics.

Membrane Lipid Replacement for chronic illnesses, aging and cancer using oral glycerolphospholipid formulations with fructooligosaccharides to restore phospholipid function in cellular membranes, organelles, cells and tissues.

Science.gov (United States)

Nicolson, Garth L; Ash, Michael E

2017-09-01

Membrane Lipid Replacement is the use of functional, oral supplements containing mixtures of cell membrane glycerolphospholipids, plus fructooligosaccharides (for protection against oxidative, bile acid and enzymatic damage) and antioxidants, in order to safely replace damaged, oxidized, membrane phospholipids and restore membrane, organelle, cellular and organ function. Defects in cellular and intracellular membranes are characteristic of all chronic medical conditions, including cancer, and normal processes, such as aging. Once the replacement glycerolphospholipids have been ingested, dispersed, complexed and transported, while being protected by fructooligosaccharides and several natural mechanisms, they can be inserted into cell membranes, lipoproteins, lipid globules, lipid droplets, liposomes and other carriers. They are conveyed by the lymphatics and blood circulation to cellular sites where they are endocytosed or incorporated into or transported by cell membranes. Inside cells the glycerolphospholipids can be transferred to various intracellular membranes by lipid globules, liposomes, membrane-membrane contact or by lipid carrier transfer. Eventually they arrive at their membrane destinations due to 'bulk flow' principles, and there they can stimulate the natural removal and replacement of damaged membrane lipids while undergoing further enzymatic alterations. Clinical trials have shown the benefits of Membrane Lipid Replacement in restoring mitochondrial function and reducing fatigue in aged subjects and chronically ill patients. Recently Membrane Lipid Replacement has been used to reduce pain and other symptoms as well as removing hydrophobic chemical contaminants, suggesting that there are additional new uses for this safe, natural medicine supplement. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights

Tumor cell invasion of collagen matrices requires coordinate lipid agonist-induced G-protein and membrane-type matrix metalloproteinase-1-dependent signaling

Directory of Open Access Journals (Sweden)

Anthis Nicholas J

2006-12-01

Full Text Available Abstract Background Lysophosphatidic acid (LPA and sphingosine 1-phosphate (S1P are bioactive lipid signaling molecules implicated in tumor dissemination. Membrane-type matrix metalloproteinase 1 (MT1-MMP is a membrane-tethered collagenase thought to be involved in tumor invasion via extracellular matrix degradation. In this study, we investigated the molecular requirements for LPA- and S1P-regulated tumor cell migration in two dimensions (2D and invasion of three-dimensional (3D collagen matrices and, in particular, evaluated the role of MT1-MMP in this process. Results LPA stimulated while S1P inhibited migration of most tumor lines in Boyden chamber assays. Conversely, HT1080 fibrosarcoma cells migrated in response to both lipids. HT1080 cells also markedly invaded 3D collagen matrices (~700 μm over 48 hours in response to either lipid. siRNA targeting of LPA1 and Rac1, or S1P1, Rac1, and Cdc42 specifically inhibited LPA- or S1P-induced HT1080 invasion, respectively. Analysis of LPA-induced HT1080 motility on 2D substrates vs. 3D matrices revealed that synthetic MMP inhibitors markedly reduced the distance (~125 μm vs. ~45 μm and velocity of invasion (~0.09 μm/min vs. ~0.03 μm/min only when cells navigated 3D matrices signifying a role for MMPs exclusively in invasion. Additionally, tissue inhibitors of metalloproteinases (TIMPs-2, -3, and -4, but not TIMP-1, blocked lipid agonist-induced invasion indicating a role for membrane-type (MT-MMPs. Furthermore, MT1-MMP expression in several tumor lines directly correlated with LPA-induced invasion. HEK293s, which neither express MT1-MMP nor invade in the presence of LPA, were transfected with MT1-MMP cDNA, and subsequently invaded in response to LPA. When HT1080 cells were seeded on top of or within collagen matrices, siRNA targeting of MT1-MMP, but not other MMPs, inhibited lipid agonist-induced invasion establishing a requisite role for MT1-MMP in this process. Conclusion LPA is a

Relationships between physical activity, physical fitness, somatic fitness, and coordination along childhood and adolescence

Directory of Open Access Journals (Sweden)

João Paulo Saraiva

2010-12-01

Full Text Available The two main goals of this review were to understand how the relationships between physical activity, physical fitness, somatic fitness, and coordination are established along the motor development of children and adolescents, and how they would influence their future lives. The web based bibliographic database B-On was searched for peer-reviewed publications during the last decade (2000 to 2009. Search criteria included all articles on relationships between any two of the above named factors. Although different methodological designs and variables were found as markers for the same factor, overall results suggested the existence of a clear positive relationship among physical activity, physical fitness, somatic fitness, and coordination from childhood to adolescence, with a special relevance for the relationship between physical activity and coordination. It was also noted a renewed interest on physical activity and motor coordination developmental characteristics and relationships as well as on their lifelong health effects.

Relationships between physical activity, physical fitness, somatic fitness, and coordination along childhood and adolescence

Directory of Open Access Journals (Sweden)

J.P. Saraiva

2010-01-01

Full Text Available The two main goals of this review were to understand how the relationships between physical activity, physical fitness, somatic fitness, and coordination are established along the motor development of children and adolescents, and how they would influence their future lives. The web based bibliographic database B-On was searched for peer-reviewed publications during the last decade (2000 to 2009. Search criteria included all articles on relationships between any two of the above named factors. Although different methodological designs and variables were found as markers for the same factor, overall results suggested the existence of a clear positive relationship among physical activity, physical fitness, somatic fitness, and coordination from childhood to adolescence, with a special relevance for the relationship between physical activity and coordination. It was also noted a renewed interest on physical activity and motor coordination developmental characteristics and relationships as well as on their lifelong health effects.

DEVELOPMENT OF COORDINATION ABILITIES OF FUTURE TEACHERS OF PHYSICAL TRAINING IN THE TRAINING PROCESS

Directory of Open Access Journals (Sweden)

Aleksandr Nikolaevich Shutov

2015-02-01

Full Text Available The article presents the results of implementing the methods of development coordination abilities in students of different sports specializations, students at the Faculty of Physical Education in the process of training in gymnastics. In the content of the classes includes a range of applied exercises with rotation in different planes of space, as a support, and the unsupported position, as well as their implementation in different directions of motion.The purpose - to improve the methods of development of coordination abilities of future teachers of physical culture in the process of training.Methodology development of coordination abilities based on the use of compound exercises with rotation in different planes of the space in the support and unsupported posture.Results. As a result of the development of methods of coordination abilities of the students showed a significant gain significant results when performing jumps with rotation (p <0.05. Significant increase was seen in the results of the students involved in wrestling, the results of which have reached the indicators close to the values typical for students specializing in gymnastics.The average value of the expert evaluation of the motor action from the arsenal of acrobatics and exercises on the equipment the students of the experimental group was 4.7 and 4.6 points, while the traditional method for dealing with this figure is 3.4 and 3.1 point, respectively (p < 0.05.Practical implications. Technique can be used as part of training students of physical culture of pedagogical universities.

Fabrication of TiO2-modified polytetrafluoroethylene ultrafiltration membranes via plasma-enhanced surface graft pretreatment

Science.gov (United States)

Qian, Yingjia; Chi, Lina; Zhou, Weili; Yu, Zhenjiang; Zhang, Zhongzhi; Zhang, Zhenjia; Jiang, Zheng

2016-01-01

Surface hydrophilic modification of polymer ultrafiltration membrane using metal oxide represents an effective yet highly challenging solution to improve water flux and antifouling performance. Via plasma-enhanced graft of poly acryl acid (PAA) prior to coating TiO2, we successfully fixed TiO2 functional thin layer on super hydrophobic polytetrafluoroethylene (PTFE) ultrafiltration (UF) membranes. The characterization results evidenced TiO2 attached on the PTFE-based UF membranes through the chelating bidentate coordination between surface-grafted carboxyl group and Ti4+. The TiO2 surface modification may greatly reduce the water contact angle from 115.8° of the PTFE membrane to 35.0° without degradation in 30-day continuous filtration operations. The novel TiO2/PAA/PTFE membranes also exhibited excellent antifouling and self-cleaning performance due to the intrinsic hydrophilicity and photocatalysis properties of TiO2, which was further confirmed by the photo-degradation of MB under Xe lamp irradiation.

Two-World Background of Special Relativity. Part I

Directory of Open Access Journals (Sweden)

Adekugbe A. O. J.

2010-01-01

Full Text Available A new sheet of spacetime is isolated and added to the existing sheet, thereby yielding a pair of co-existing sheets ofspacetimes, which are four-dimensional inversions of each other. The separation of the spacetimes by the special-relativistic event horizon compels an interpretation of the existence of a pair of symmetrical worlds (or universes in nature. Further more, a flat two-dimensional intrinsic spacetime that underlies the flat four-dimensional spacetime in each universe is introduced. The four-dimensional spacetime is outward manifestation of the two-dimensional intrinsic spacetime, just as the Special Theory of Relativity (SR on four-dimensional spacetime is mere outward manifestation of the intrinsic Special Theory of Relativity ($phi$SR on two-dimensional intrinsic spacetime. A new set of diagrams in the two-world picture that involves relative rotation of the coordinates of the two-dimensional intrinsic spacetime is drawn and intrinsic Lorentz transformation derived from it. The Lorentz transformation in SR is then written directly from intrinsic Lorentz transformation in $phi$SR without any need to draw diagrams involving relative rotation of the coordinates of four-dimensional spacetime, as usually done until now. Indeed every result of SR can be written directly from the corresponding result of $phi$SR. The non-existence of the light cone concept in the two-world picture is shown and good prospect for making the Lorentz group SO(3,1 compact in the two-world picture is highlighted.

Two-World Background of Special Relativity. Part I

Directory of Open Access Journals (Sweden)

Adekugbe A. O. J.

2010-01-01

Full Text Available A new sheet of spacetime is isolated and added to the existing sheet, thereby yielding a pair of co-existing sheets of spacetimes, which are four-dimensional inversions of each other. The separation of the spacetimes by the special-relativistic event horizon com- pels an interpretation of the existence of a pair of symmetrical worlds (or universes in nature. Further more, a flat two-dimensional intrinsic spacetime that underlies the flat four-dimensional spacetime in each universe is introduced. The four-dimensional spacetime is outward manifestation of the two-dimensional intrinsic spacetime, just as the Special Theory of Relativity (SR on four-dimensional spacetime is mere outward manifestation of the intrinsic Special Theory of Relativity ( SR on two-dimensional intrinsic spacetime. A new set of diagrams in the two-world picture that involves rela- tive rotation of the coordinates of the two-dimensional intrinsic spacetime is drawn and intrinsic Lorentz transformation derived from it. The Lorentz transformation in SR is then written directly from intrinsic Lorentz transformation in SR without any need to draw diagrams involving relative rotation of the coordinates of four-dimensional space- time, as usually done until now. Indeed every result of SR can be written directly from the corresponding result of SR. The non-existence of the light cone concept in the two-world picture is shown and good prospect for making the Lorentz group SO(3,1 compact in the two-world picture is highlighted.

Membrane morphological study nanostructured based hydrophobic/hydrophilic applied in devices of PEMFC

International Nuclear Information System (INIS)

Loureiro, Felipe Augusto M.; Dahmouche, K; Rocco, Ana Maria

2015-01-01

The increasingly high energy demand generated by the increase of world population and consumption of fuels based on non-renewable sources has stimulated, in recent decades, the development of alternatives with less environmental impact and are based on renewable sources. Among these, the fuel cells (FC) have extremely promising possibilities. For the development of FC with market viability, it is necessary to obtain materials with optimized properties, among which the proton conducting membranes. In this work, we developed semi-interpenetrating polymer membranes (SIPN) based on diglycidyl ether of bisphenol-A (DGEBA) and polyethyleneimine (PEI), aiming their application in PEMFC. The membranes nanostructure was studied by AFM and SAXS means and it was identified ordinate hydrophobic/hydrophilic nano domains, which have determined the membrane properties, specially the proton conductivity. (author)

The changes in boxer's coordination capability indices due to the implementing acrobatic and aerobic elements

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Zinchenko I. A.

2010-04-01

Full Text Available Influence of acrobatic exercises is rotined on the co-ordinating capabilities of boxers and roles of acrobatics in the training process of boxers. In an experiment two groups of boxers took part in age 16-20 years. The uses of acrobatic elements given about efficiency are presented by sportsmen for the improvement of indexes and the increase of level is special technical activity of boxers. The changes of development of co-ordinating capabilities of boxers are rotined with the use in the training process of facilities of aerobics and acrobatics.

Roles of sex and ethnicity in procurement coordinator--family communication during the organ donation discussion.

Science.gov (United States)

Baughn, Daniel; Auerbach, Stephen M; Siminoff, Laura A

2010-09-01

Interpersonal relations with health care providers influence families' decisions to consent to solid-organ donation. However, previous research has been based on retrospective interviews with donation-eligible families and has not directly examined the interpersonal interactions between families and organ procurement coordinators. To increase understanding of the interpersonal interaction between procurement coordinators and families during the organ donation discussion, with special attention to the influence of the sex and race of the procurement coordinator and the race of the potential donor's family. A descriptive study in which standardized patients portrayed family members interacting with actual procurement coordinators in simulated donation request scenarios. Thirty-three videotaped interactions between standardized patients and 17 procurement coordinators involving 2 different scenarios depicting deceased donation were evaluated. Video recordings were rated by independent coders. Coders completed the Impact Message Inventory-Form C, the Participatory Style of Physician Scale, and the Siminoff Communication and Content and Affect Program-Global Observer Ratings scale. African American procurement coordinators, particularly African American women, were rated as more controlling and work-oriented than white procurement coordinators. Male procurement coordinators were more affiliative with the white family than the African American family, whereas female procurement coordinators were slightly less affiliative with the white family. African American procurement coordinators expressed more positive affect when interacting with the African American family than the white family, whereas the opposite was true for white procurement coordinators. Research is needed to cross-validate these exploratory findings and further examine cultural mistrust between procurement coordinators and families of ethnic minorities, especially given the negative attitudes of many

Physio-psychological Burdens and Social Restrictions on Parents of Children With Technology Dependency are Associated With Care Coordination by Nurses.

Science.gov (United States)

Suzuki, Seigo; Sato, Iori; Emoto, Shun; Kamibeppu, Kiyoko

To determine the association between parental care burdens and care coordination provided by nurses for children with technology dependency, specifically regarding physio-psychological burdens and social restrictions. A cross-sectional study was conducted between October and November 2015. Participants were recruited via home-visit nursing stations, social worker offices, and special-needs schools. A total of 246 parents of children with technology dependency completed anonymous self-report questionnaires. Parental burden was measured using the Zarit Burden Interview. Care coordination for children with technology dependency was examined using items extracted from focus group interviews involving three nursing administrators at home-visit nursing stations, two social workers, and a coordinator of school education for children with special health care needs. Multiple regression analysis was performed to examine the relationship between parental burden and care coordination among 172 parents who contracted with visiting nurses. Parents and children with nursing support were significantly younger and had higher medical care needs and higher parental role strain than those without nursing support. Care coordination from nurses predicted reduced parental burden, role strain, and personal strain (β=-0.247, p=0.002; β=-0.272, p=0.001; β=-0.221, p=0.009, respectively). Nurses' care coordination appears to be associated with a reduction in parents' care burden resulting from home medical care of children with technology dependency, especially the social restrictions and physio-psychological burdens. Strengthening nursing functioning as care coordinators may contribute to reducing care burdens for parents of children with technology dependency. Copyright © 2017 Elsevier Inc. All rights reserved.

The effectiveness of the developed program of 10-13 years girls' coordinative abilities going in for calisthenics.

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Belokopitova G.A.

2011-06-01

Full Text Available It's developed and practically based the program on developing coordinative abilities according to age group of 10-13 years old gymnastics. This program is for special stage of training and it is aimed for developing coordinating abilities connected to individual-psychological peculiarities of girls going for gymnastics. It was shown that sport result of 10-13 years girls' influences on index of psycho-moving futures - abilities for correction of their actions to free mobilization and moving coordination during performing fast work. It can be explained that index which is being expected shows the set of time-hour moves and allows evaluating gymnasts moves.

Data on flow cell optimization for membrane-based electrokinetic energy conversion

Directory of Open Access Journals (Sweden)

David Nicolas Østedgaard-Munck

2017-12-01

Full Text Available This article elaborates on the design and optimization of a specialized flow cell for the measurement of direct conversion of pressure into electrical energy (Electrokinetic Energy Conversion, EKEC which has been presented in Østedgaard-Munck et al. (2017 [1]. Two main flow cell parameters have been monitored and optimized: A the hydraulic pressure profile on each side of the membrane introduced by pumps recirculating the electrolyte solution through the flow fields and B the electrical resistance between the current collectors across the combined flow cell. The latter parameter has been measured using four-point Electrochemical Impedance spectroscopy (EIS for different flow rates and concentrations. The total cell resistance consists of contributions from different components: the membrane (Rmem, anode charge transfer (RA, cathode charge transfer (RC, and ion diffusion in the porous electrodes (RD.The intrinsic membrane properties of Nafion 117 has been investigated experimentally in LiI/I2 solutions with concentrations ranging between 0.06 and 0.96 M and used to identify the preferred LiI/I2 solution concentration. This was achieved by measuring the solution uptake, internal solution concentration and ion exchange capacity. The membrane properties were further used to calculate the transport coefficients and electrokinetic Figure of merit in terms of the Uniform potential and Space charge models. Special attention has been put on the streaming potential coefficient which is an intrinsic property. Keywords: Electrokinetic energy conversion, Electrochemical flow cell, Conversion efficiency

Influence of photo-induced superhydrophilicity of titanium dioxide nanoparticles on the anti-fouling performance of ultrafiltration membranes

Energy Technology Data Exchange (ETDEWEB)

Madaeni, S.S., E-mail: smadaeni@yahoo.com [Membrane Research Center, Department of Chemical Engineering, Razi University, Tagh Bostan, 67149 Kermanshah (Iran, Islamic Republic of); Ghaemi, N. [Membrane Research Center, Department of Chemical Engineering, Razi University, Tagh Bostan, 67149 Kermanshah (Iran, Islamic Republic of); Department of Chemical Engineering, Kermanshah University of Technology, Kermanshah (Iran, Islamic Republic of); Alizadeh, A. [Nanoscience and Nanotechnology Research Centre (NNRC), Faculty of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of); Joshaghani, M. [Faculty of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of)

2011-05-01

Fouling is one of the most present prominent problems in almost all membrane processes. An increase in the membrane hydrophilicity is one of the effective ways to improve the membrane resistance to fouling. In this research, TiO{sub 2} nanoparticles were deposited on the surface of composite ultrafiltration (UF) membrane, and then irradiated by ultraviolet (UV) light. The coating of the membrane surface with TiO{sub 2} nanoparticles and radiation with (UV) light led to the considerable increase of hydrophilicity on the membrane surface. The deposition of TiO{sub 2} nanoparticles was carried out through coordinance bonds with OH functional groups of the polymer on the membrane surface. The flux through a coated and (UV) light radiated membrane was increased to a large extent compared to a virgin membrane. In this research, the effect of different concentrations of TiO{sub 2} nanoparticles in the presence and absence of (UV) irradiation was investigated, and the role of increasing of hydrophilicity on the anti-fouling property of membranes was studied. In order to characterize the membranes FTIR, XRD, SEM, water contact angle and cross-flow filtration were employed. This procedure is a useful technique for improvement of hydrophilicity to decrease (increase) fouling (anti-fouling performance) and enhance the permeation of membranes.

Real symplectic formulation of local special geometry

CERN Document Server

Ferrara, Sergio; Ferrara, Sergio; Macia, Oscar

2006-01-01

We consider a formulation of local special geometry in terms of Darboux special coordinates $P^I=(p^i,q_i)$, $I=1,...,2n$. A general formula for the metric is obtained which is manifestly $\\mathbf{Sp}(2n,\\mathbb{R})$ covariant. Unlike the rigid case the metric is not given by the Hessian of the real function $S(P)$ which is the Legendre transform of the imaginary part of the holomorphic prepotential. Rather it is given by an expression that contains $S$, its Hessian and the conjugate momenta $S_I=\\frac{\\partial S}{\\partial P^I}$. Only in the one-dimensional case ($n=1$) is the real (two-dimensional) metric proportional to the Hessian with an appropriate conformal factor.

Coordination chemistry of technetium as related to nuclear medicine

International Nuclear Information System (INIS)

Srivastava, S.C.; Richards, P.

1982-01-01

Significant advances have been made in the area of technetium coordination chemistry during the last five years. The main driving force behind this recent surge of interest in the field has been due to the practical application of technetium-99m in the rapidly growing speciality of nuclear medicine. Technetium-99 is one of the products of nuclear fission reactions, but it was the development of the molybdenum-99-technetium-99m generator about two decades ago that provided the basis for the development of radiopharmaceuticals routinely used in modern diagnostic applications. The chemistry of this element has proven to be quite rich owing to its multiple oxidation states and variable geometry. This can be attributed to its position in the middle of the periodic table. Diagnostic radiopharmaceuticals comprise predominantly III, IV and V oxidation states of Tc and involve a variety of coordination complexes. Even though the chemistry of Tc has been slow to evolve, recent synthetic advances have provided a more scientific basis for the study of a number of compounds with diverse coordination geometries and structures. Ligands with oxygen, nitrogen and sulfur donor atoms have been utilized to elucidate various aspects of the coordination chemistry of Tc. Single crystal X-ray structural analysis has been extensively used to characterize Tc complexes and thus construct a firm foundation for the study of synthetic and mechanistic aspects of the chemistry of this element. (author)

Mechanical feedback coordinates cell wall expansion and assembly in yeast mating morphogenesis

Science.gov (United States)

2018-01-01

The shaping of individual cells requires a tight coordination of cell mechanics and growth. However, it is unclear how information about the mechanical state of the wall is relayed to the molecular processes building it, thereby enabling the coordination of cell wall expansion and assembly during morphogenesis. Combining theoretical and experimental approaches, we show that a mechanical feedback coordinating cell wall assembly and expansion is essential to sustain mating projection growth in budding yeast (Saccharomyces cerevisiae). Our theoretical results indicate that the mechanical feedback provided by the Cell Wall Integrity pathway, with cell wall stress sensors Wsc1 and Mid2 increasingly activating membrane-localized cell wall synthases Fks1/2 upon faster cell wall expansion, stabilizes mating projection growth without affecting cell shape. Experimental perturbation of the osmotic pressure and cell wall mechanics, as well as compromising the mechanical feedback through genetic deletion of the stress sensors, leads to cellular phenotypes that support the theoretical predictions. Our results indicate that while the existence of mechanical feedback is essential to stabilize mating projection growth, the shape and size of the cell are insensitive to the feedback. PMID:29346368

APBSmem: a graphical interface for electrostatic calculations at the membrane.

Directory of Open Access Journals (Sweden)

Keith M Callenberg

2010-09-01

Full Text Available Electrostatic forces are one of the primary determinants of molecular interactions. They help guide the folding of proteins, increase the binding of one protein to another and facilitate protein-DNA and protein-ligand binding. A popular method for computing the electrostatic properties of biological systems is to numerically solve the Poisson-Boltzmann (PB equation, and there are several easy-to-use software packages available that solve the PB equation for soluble proteins. Here we present a freely available program, called APBSmem, for carrying out these calculations in the presence of a membrane. The Adaptive Poisson-Boltzmann Solver (APBS is used as a back-end for solving the PB equation, and a Java-based graphical user interface (GUI coordinates a set of routines that introduce the influence of the membrane, determine its placement relative to the protein, and set the membrane potential. The software Jmol is embedded in the GUI to visualize the protein inserted in the membrane before the calculation and the electrostatic potential after completing the computation. We expect that the ease with which the GUI allows one to carry out these calculations will make this software a useful resource for experimenters and computational researchers alike. Three examples of membrane protein electrostatic calculations are carried out to illustrate how to use APBSmem and to highlight the different quantities of interest that can be calculated.

Deorphanizing the human transmembrane genome: A landscape of uncharacterized membrane proteins.

Science.gov (United States)

Babcock, Joseph J; Li, Min

2014-01-01

The sequencing of the human genome has fueled the last decade of work to functionally characterize genome content. An important subset of genes encodes membrane proteins, which are the targets of many drugs. They reside in lipid bilayers, restricting their endogenous activity to a relatively specialized biochemical environment. Without a reference phenotype, the application of systematic screens to profile candidate membrane proteins is not immediately possible. Bioinformatics has begun to show its effectiveness in focusing the functional characterization of orphan proteins of a particular functional class, such as channels or receptors. Here we discuss integration of experimental and bioinformatics approaches for characterizing the orphan membrane proteome. By analyzing the human genome, a landscape reference for the human transmembrane genome is provided.

Relativistic effects in a rotating coordinate system

International Nuclear Information System (INIS)

Chugreev, Y.V.

1989-01-01

The general approach to calculating various physical effects in a rotating, noninertial reference frame based on the tetrad formalism for observables is discussed. It is shown that the method based on the search for the ''true'' coordinate transformation from an inertial to the rotating frame is ill-founded. Most special relativistic effects in a rotating frame have been calculated without any nonrelativistic restrictions. It is shown how simple physical experiments can be used to determine whether a circle is at rest in the equatorial plane of a Kerr--Newman gravitational source in the relativistic theory of gravity or is rotating about an axis through its center

How Students Learn from Multiple Contexts and Definitions: Proper Time as a Coordination Class

Science.gov (United States)

Levrini, Olivia; diSessa, Andrea A.

2008-01-01

This article provides an empirical analysis of a single classroom episode in which students reveal difficulties with the concept of proper time in special relativity but slowly make progress in improving their understanding. The theoretical framework used is "coordination class theory," which is an evolving model of concepts and conceptual change.…

The Road not Taken: Less Traveled Roads from the TGN to the Plasma Membrane.

Science.gov (United States)

Spang, Anne

2015-03-10

The trans-Golgi network functions in the distribution of cargo into different transport vesicles that are destined to endosomes, lysosomes and the plasma membrane. Over the years, it has become clear that more than one transport pathway promotes plasma membrane localization of proteins. In spite of the importance of temporal and spatial control of protein localization at the plasma membrane, the regulation of sorting into and the formation of different transport containers are still poorly understood. In this review different transport pathways, with a special emphasis on exomer-dependent transport, and concepts of regulation and sorting at the TGN are discussed.

Amniotic Membrane Transplant with a Special Technique (Motowa's Sandwich Technique) in Mooren's Ulcer.

Science.gov (United States)

Al Motowa, Saeed; Al Zobidi, Mohammed

2015-01-01

To illustrate amniotic membrane transplant (AMT) with a novel surgical technique ("sandwich technique") for treating patients with malignant Mooren's ulcer. A case report of a patient with bilateral, malignant Mooren's ulcer who had undergone systemic steroid therapy and topical immunosuppresive therapy to stabilize his condition. However, perforation of cornea occurred in one eye. AMT with a new surgical technique ("Motowa's sandwich technique") was performed to treat this case. On the 1(st) day postoperatively, there was no pain, no photophobia, and visual acuity was same as preoperatively. At 4 weeks postoperatively, visual acuity improved in the right eye to 20/160 with pinhole, and there was no fluorescein staining. The right eye was quiet. Amniotic membrane transplant with "Motowa's sandwich technique" resulted in the preservation of the anatomical integrity and progression of disease was halted along with an improved vision. This technique is a novel surgical modality in treating Mooren's ulcer. Further study on a large cohort of patients is required for evidence-based data to verify the outcome of this initial case report.

A New type of conserved quantity deduced from Mei symmetry of nonholonomic systems in terms of quasi-coordinates

International Nuclear Information System (INIS)

Ting, Pang; Jian-Hui, Fang; Ming-Jiang, Zhang; Peng, Lin; Kai, Lu

2009-01-01

This paper studies the new type of conserved quantity which is directly induced by Mei symmetry of nonholonomic systems in terms of quasi-coordinates. A coordination function is introduced, and the conditions for the existence of the new conserved quantities as well as their forms are proposed. Some special cases are given to illustrate the generalized significance of the new type conserved quantity. Finally, an illustrated example is given to show the application of the nonholonomic system's results. (general)

Protein receptor-independent plasma membrane remodeling by HAMLET: a tumoricidal protein-lipid complex.

Science.gov (United States)

Nadeem, Aftab; Sanborn, Jeremy; Gettel, Douglas L; James, Ho C S; Rydström, Anna; Ngassam, Viviane N; Klausen, Thomas Kjær; Pedersen, Stine Falsig; Lam, Matti; Parikh, Atul N; Svanborg, Catharina

2015-11-12

A central tenet of signal transduction in eukaryotic cells is that extra-cellular ligands activate specific cell surface receptors, which orchestrate downstream responses. This ''protein-centric" view is increasingly challenged by evidence for the involvement of specialized membrane domains in signal transduction. Here, we propose that membrane perturbation may serve as an alternative mechanism to activate a conserved cell-death program in cancer cells. This view emerges from the extraordinary manner in which HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) kills a wide range of tumor cells in vitro and demonstrates therapeutic efficacy and selectivity in cancer models and clinical studies. We identify a ''receptor independent" transformation of vesicular motifs in model membranes, which is paralleled by gross remodeling of tumor cell membranes. Furthermore, we find that HAMLET accumulates within these de novo membrane conformations and define membrane blebs as cellular compartments for direct interactions of HAMLET with essential target proteins such as the Ras family of GTPases. Finally, we demonstrate lower sensitivity of healthy cell membranes to HAMLET challenge. These features suggest that HAMLET-induced curvature-dependent membrane conformations serve as surrogate receptors for initiating signal transduction cascades, ultimately leading to cell death.

The use of the co-ordinate measuring machine for the study of three-dimensional biomechanics of the knee.

Science.gov (United States)

Veselko, M; Jenko, M; Lipuscek, I

1998-07-01

Original methodology for the study of three-dimensional biomechanics of the knee is presented in the paper. Defining the geometry of the rigid body in the body-fixed reference frame and the orientation of the body-fixed reference frame in the global co-ordinate system are the theoretic basis. The data in the form of co-ordinates of the Cartesian frame are gathered by the co-ordinate measuring machine and analysed by specially computer program. The theory and a practical example of the study of the three-dimensional biomechanics of the knee are presented. Various possibilities of the use of the methodology are discussed.

To Ingest or Rest? Specialized Roles of Lateral Hypothalamic Area Neurons in Coordinating Energy Balance

Directory of Open Access Journals (Sweden)

Juliette A. Brown

2015-02-01

Full Text Available Survival depends on an organism’s ability to sense nutrient status and accordingly regulate intake and energy expenditure behaviors. Uncoupling of energy sensing and behavior, however, underlies energy balance disorders such as anorexia or obesity. The hypothalamus regulates energy balance, and in particular the lateral hypothalamic area (LHA is poised to coordinate peripheral cues of energy status and behaviors that impact weight, such as drinking, locomotor behavior, arousal/sleep and autonomic output. There are several populations of LHA neurons that are defined by their neuropeptide content and contribute to energy balance. LHA neurons that express the neuropeptides melanin-concentrating hormone (MCH or orexins/hypocretins (OX are best characterized and these neurons play important roles in regulating ingestion, arousal, locomotor behavior and autonomic function via distinct neuronal circuits. Recently, another population of LHA neurons containing the neuropeptide Neurotensin (Nts has been implicated in coordinating anorectic stimuli and behavior to regulate hydration and energy balance. Understanding the specific roles of MCH, OX and Nts neurons in harmonizing energy sensing and behavior thus has the potential to inform pharmacological strategies to modify behaviors and treat energy balance disorders.

Specific membrane lipid composition is important for plasmodesmata function in Arabidopsis.

Science.gov (United States)

Grison, Magali S; Brocard, Lysiane; Fouillen, Laetitia; Nicolas, William; Wewer, Vera; Dörmann, Peter; Nacir, Houda; Benitez-Alfonso, Yoselin; Claverol, Stéphane; Germain, Véronique; Boutté, Yohann; Mongrand, Sébastien; Bayer, Emmanuelle M

2015-04-01

Plasmodesmata (PD) are nano-sized membrane-lined channels controlling intercellular communication in plants. Although progress has been made in identifying PD proteins, the role played by major membrane constituents, such as the lipids, in defining specialized membrane domains in PD remains unknown. Through a rigorous isolation of "native" PD membrane fractions and comparative mass spectrometry-based analysis, we demonstrate that lipids are laterally segregated along the plasma membrane (PM) at the PD cell-to-cell junction in Arabidopsis thaliana. Remarkably, our results show that PD membranes display enrichment in sterols and sphingolipids with very long chain saturated fatty acids when compared with the bulk of the PM. Intriguingly, this lipid profile is reminiscent of detergent-insoluble membrane microdomains, although our approach is valuably detergent-free. Modulation of the overall sterol composition of young dividing cells reversibly impaired the PD localization of the glycosylphosphatidylinositol-anchored proteins Plasmodesmata Callose Binding 1 and the β-1,3-glucanase PdBG2 and altered callose-mediated PD permeability. Altogether, this study not only provides a comprehensive analysis of the lipid constituents of PD but also identifies a role for sterols in modulating cell-to-cell connectivity, possibly by establishing and maintaining the positional specificity of callose-modifying glycosylphosphatidylinositol proteins at PD. Our work emphasizes the importance of lipids in defining PD membranes. © 2015 American Society of Plant Biologists. All rights reserved.

Lipid self-assembly and lectin-induced reorganization of the plasma membrane.

Science.gov (United States)

Sych, Taras; Mély, Yves; Römer, Winfried

2018-05-26

The plasma membrane represents an outstanding example of self-organization in biology. It plays a vital role in protecting the integrity of the cell interior and regulates meticulously the import and export of diverse substances. Its major building blocks are proteins and lipids, which self-assemble to a fluid lipid bilayer driven mainly by hydrophobic forces. Even if the plasma membrane appears-globally speaking-homogeneous at physiological temperatures, the existence of specialized nano- to micrometre-sized domains of raft-type character within cellular and synthetic membrane systems has been reported. It is hypothesized that these domains are the origin of a plethora of cellular processes, such as signalling or vesicular trafficking. This review intends to highlight the driving forces of lipid self-assembly into a bilayer membrane and the formation of small, transient domains within the plasma membrane. The mechanisms of self-assembly depend on several factors, such as the lipid composition of the membrane and the geometry of lipids. Moreover, the dynamics and organization of glycosphingolipids into nanometre-sized clusters will be discussed, also in the context of multivalent lectins, which cluster several glycosphingolipid receptor molecules and thus create an asymmetric stress between the two membrane leaflets, leading to tubular plasma membrane invaginations.This article is part of the theme issue 'Self-organization in cell biology'. © 2018 The Author(s).

Coordination in contractual relations: Some preliminary findings from the Malaysian housing industry

Directory of Open Access Journals (Sweden)

Suraya Ismail

2008-12-01

Full Text Available The traditional general procurement route found in many housing projects in Malaysia is conceptualized as a governance structure following the transaction cost economics (TCE approach. This approach has been used to examine governance structures in different economic sectors in several countries but evidence of its use in the context of developing countries is limited. This lack of evidence has prompted the authors to conduct a preliminary study to ascertain whether a TCE approach can explain construction governance structures in developing countries. This research does not discuss the trade-off that governs the choice of hybrids, market or hierarchies for organizing transactions. Rather, it takes advantage of existing research to substantiate the specific properties of hybrid organizations as governance structures. The main focus is coordination. Coordination is specified at two levels. At Level 1 is the coordination of specialization (i.e. the formation of the project team members and at Level 2 is the coordination mode of the contracting parties (client and contractor and the agents involved (the lead designer and project manage r. A case survey method was adopted. Preliminary findings seem to suggest that clients have used hierarchical themes in the contracts and high powered incentives to coordinate with in the contracting parties. The research findings suggest that all participants involved in the sample studied used governance structures symptomatic of a hybrid organization.

Coordinating IMC-PID and adaptive SMC controllers for a PEMFC.

Science.gov (United States)

Wang, Guo-Liang; Wang, Yong; Shi, Jun-Hai; Shao, Hui-He

2010-01-01

For a Proton Exchange Membrane Fuel Cell (PEMFC) power plant with a methanol reformer, the process parameters and power output are considered simultaneously to avoid violation of the constraints and to keep the fuel cell power plant safe and effective. In this paper, a novel coordinating scheme is proposed by combining an Internal Model Control (IMC) based PID Control and adaptive Sliding Mode Control (SMC). The IMC-PID controller is designed for the reformer of the fuel flow rate according to the expected first-order dynamic properties. The adaptive SMC controller of the fuel cell current has been designed using the constant plus proportional rate reaching law. The parameters of the SMC controller are adaptively tuned according to the response of the fuel flow rate control system. When the power output controller feeds back the current references to these two controllers, the coordinating controllers system works in a system-wide way. The simulation results of the PEMFC power plant demonstrate the effectiveness of the proposed method. 2009 ISA. Published by Elsevier Ltd. All rights reserved.

75 FR 32164 - Office of Special Education and Rehabilitative Services; Overview Information; Regional...

Science.gov (United States)

2010-06-07

... communication or language preference. Interpreter means individuals, both hearing and deaf, who provide... vocational rehabilitation (VR) agencies), VR State coordinators for the deaf, rehabilitation counselors for... preferences within the deaf, hard of hearing, and deaf-blind communities through strands of specialized...

Enhancing success in transition service coordinators: use of transformational leadership.

Science.gov (United States)

Rearick, Ellen

2007-01-01

The lifespan of children with special healthcare needs has been extended because of improved technology and medical advances. Successful transition to the adult arena of healthcare, social services, and education by adolescents with special healthcare needs (ASHCN) is lacking. The transition service coordinator (TSC) is a multifaceted role of advanced practice nursing that provides highly specialized transition services to adolescents with special healthcare needs. The use of key concepts from the transformational leadership theory may improve healthcare outcomes. This article applies to pediatric and adult primary care and case management services that serve adolescents with special healthcare needs. Employing key concepts of transformational leadership theory will enhance the success of the TSC to improve both collaboration among stakeholders in the transitional team and young adults' transition to the world of adult services. Enhanced communication resulting in improved sharing of information, understanding of the stakeholder roles, and provision of formal linkages between pediatric and adult medical providers is a significant outcome affecting the ASHCN. Improved collaboration will produce a smooth transition for the ASHCN to the world of adult social services education, and employment. Incorporating the transformational leadership dimensions of idealized influence, inspirational motivation intellectual stimulation, and individualized consideration will enhance the ability of the TSC to improve collaboration among stakeholders in the transitional team and the quality of services for the ASHCN.

Special Geometry and Automorphic Forms

CERN Document Server

Berglund, P; Wyllard, N; Berglund, Per; Henningson, Mans; Wyllard, Niclas

1997-01-01

We consider special geometry of the vector multiplet moduli space in compactifications of the heterotic string on $K3 \\times T^2$ or the type IIA string on $K3$-fibered Calabi-Yau threefolds. In particular, we construct a modified dilaton that is invariant under $SO(2, n; Z)$ T-duality transformations at the non-perturbative level and regular everywhere on the moduli space. The invariant dilaton, together with a set of other coordinates that transform covariantly under $SO(2, n; Z)$, parameterize the moduli space. The construction involves a meromorphic automorphic function of $SO(2, n; Z)$, that also depends on the invariant dilaton. In the weak coupling limit, the divisor of this automorphic form is an integer linear combination of the rational quadratic divisors where the gauge symmetry is enhanced classically. We also show how the non-perturbative prepotential can be expressed in terms of meromorphic automorphic forms, by expanding a T-duality invariant quantity both in terms of the standard special coord...

Unstable ‘black branes’ from scaled membranes at large D

Energy Technology Data Exchange (ETDEWEB)

Dandekar, Yogesh; Mazumdar, Subhajit; Minwalla, Shiraz; Saha, Arunabha [Department of Theoretical Physics, Tata Institute of Fundamental Research,Homi Bhabha Road, Mumbai, 400005 (India)

2016-12-28

It has recently been demonstrated that the dynamics of black holes at large D can be recast as a set of non gravitational membrane equations. These membrane equations admit a simple static solution with shape S{sup D−p−2}×R{sup p,1}. In this note we study the equations for small fluctuations about this solution in a limit in which amplitude and length scale of the fluctuations are simultaneously scaled to zero as D is taken to infinity. We demonstrate that the resultant nonlinear equations, which capture the Gregory-Laflamme instability and its end point, exactly agree with the effective dynamical ‘black brane’ equations of Emparan Suzuki and Tanabe. Our results thus identify the ‘black brane’ equations as a special limit of the membrane equations and so unify these approaches to large D black hole dynamics.

Membranes, methods of making membranes, and methods of separating gases using membranes

Science.gov (United States)

Ho, W. S. Winston

2012-10-02

Membranes, methods of making membranes, and methods of separating gases using membranes are provided. The membranes can include at least one hydrophilic polymer, at least one cross-linking agent, at least one base, and at least one amino compound. The methods of separating gases using membranes can include contacting a gas stream containing at least one of CO.sub.2, H.sub.2S, and HCl with one side of a nonporous and at least one of CO.sub.2, H.sub.2S, and HCl selectively permeable membrane such that at least one of CO.sub.2, H.sub.2S, and HCl is selectively transported through the membrane.

The role of hospitals in bridging the care continuum: a systematic review of coordination of care and follow-up for adults with chronic conditions.

Science.gov (United States)

De Regge, Melissa; De Pourcq, Kaat; Meijboom, Bert; Trybou, Jeroen; Mortier, Eric; Eeckloo, Kristof

2017-08-09

Multiple studies have investigated the outcome of integrated care programs for chronically ill patients. However, few studies have addressed the specific role hospitals can play in the downstream collaboration for chronic disease management. Our objective here is to provide a comprehensive overview of the role of the hospitals by synthesizing the advantages and disadvantages of hospital interference in the chronic discourse for chronically ill patients found in published empirical studies. Systematic literature review. Two reviewers independently investigated relevant studies using a standardized search strategy. Thirty-two articles were included in the systematic review. Overall, the quality of the included studies is high. Four important themes were identified: the impact of transitional care interventions initiated from the hospital's side, the role of specialized care settings, the comparison of inpatient and outpatient care, and the effect of chronic care coordination on the experience of patients. Our results show that hospitals can play an important role in transitional care interventions and the coordination of chronic care with better outcomes for the patients by taking a leading role in integrated care programs. Above that, the patient experiences are positively influenced by the coordinating role of a specialist. Specialized care settings, as components of the hospital, facilitate the coordination of the care processes. In the future, specialized care centers and primary care could play a more extensive role in care for chronic patients by collaborating.

Internal humidifying of PEM [Proton Exchange Membrane] fuel cells

Energy Technology Data Exchange (ETDEWEB)

Staschewski, D [Karlsruhe Research Center (FZK), Karlsruhe (Germany). Inst. for Neutron Physics and Reactor Technics

1996-12-01

Hydrogen fuel cells (FC) for vehicular traction should stand out for a car-specific lightweight design. As regards PEMFC systems containing proton exchange membranes, this quality can be considerably improved by introducing porous bipolar plates which are conditioned by a water loop and deliver hot humidifying water to the adjacent membrane-electrode assembly (MEA). According to the principle of internal humidification here indicated special fuel cells based on sintered fiber and powder graphite were manufactured at FZK on a semi-technical scale. Self-made Pt/C electrodes hotpressed onto Nafion resulted in currents up to 200 A with pure oxygen as oxidant, providing the precondition for detailed studies of turnover and drainage rates within a monocell test arrangement. (author)

General Fit-Basis Functions and Specialized Coordinates in an Adaptive Density-Guided Approach to Potential Energy Surfaces

DEFF Research Database (Denmark)

Klinting, Emil Lund; Thomsen, Bo; Godtliebsen, Ian Heide

. This results in a decreased number of single point calculations required during the potential construction. Especially the Morse-like fit-basis functions are of interest, when combined with rectilinear hybrid optimized and localized coordinates (HOLCs), which can be generated as orthogonal transformations......The overall shape of a molecular energy surface can be very different for different molecules and different vibrational coordinates. This means that the fit-basis functions used to generate an analytic representation of a potential will be met with different requirements. It is therefore worthwhile...... single point calculations when constructing the molecular potential. We therefore present a uniform framework that can handle general fit-basis functions of any type which are specified on input. This framework is implemented to suit the black-box nature of the ADGA in order to avoid arbitrary choices...

Impact of Relational Coordination on Nurse Job Satisfaction, Work Engagement and Burnout: Achieving the Quadruple Aim.

Science.gov (United States)

Havens, Donna Sullivan; Gittell, Jody Hoffer; Vasey, Joseph

2018-03-01

To explore how relational coordination, known to enhance quality and efficiency outcomes for patients and hospitals, impacts direct care nurse outcomes such as burnout, work engagement, and job satisfaction, addressing the "Quadruple Aim," to improve the experience of providing care. Hospitals are complex organizations in which multiple providers work interdependently, under conditions of uncertainty and time constraints, to deliver safe quality care despite differences in specialization, training, and status. Relational coordination-communicating and relating for the purpose of task integration-is known to improve quality, safety, and efficiency under these conditions, but less is known about its impact on the well-being of direct care providers themselves. Surveys measuring relational coordination among nurses and other types of providers as well as job-related outcomes in 5 acute care community hospitals were completed by direct care RNs. Relational coordination was significantly related to increased job satisfaction, increased work engagement, and reduced burnout. Relational coordination contributes to the well-being of direct care nurses, addressing the Quadruple Aim by improving the experience of providing care.

Integration of membrane filtration and photoelectrocatalysis using a TiO{sub 2}/carbon/Al{sub 2}O{sub 3} membrane for enhanced water treatment

Energy Technology Data Exchange (ETDEWEB)

Wang, Guanlong; Chen, Shuo, E-mail: shuochen@dlut.edu.cn; Yu, Hongtao; Quan, Xie

2015-12-15

Highlights: • Membrane filtration was integrated with photoelectrocatalysis for water treatment. • This integrated process (PECM) displays good antifouling capacity in NOMs removal. • PECM process enables efficient removal of chemical contaminants (e.g., RhB). • Enhanced charge separation of PECM process leads to its improved performance. - Abstract: Coupling membrane filtration with photocatalysis provides multifunction involving filtration and photocatalytic degradation for removing pollutants from water, but the performance of photocatalytic membrane is limited due to the quick recombination of photogenerated electron-holes in photocatalytic layer. Herein, a TiO{sub 2}/carbon/Al{sub 2}O{sub 3} membrane was designed and constructed through sequentially depositing graphitic carbon layer with good electro-conductivity and TiO{sub 2} nanoparticles layer with photocatalytic activity on Al{sub 2}O{sub 3} membrane support. When light irradiated on the membrane with a voltage supply, the photogenerated electrons could be drained from photocatalytic layer and separated with holes efficiently, thus endowing the membrane with photoelectrocatalytic function. Membrane performance tests indicated that the photoelectrocatalytic membrane filtration (PECM) showed improved removal of natural organic matters (NOMs) and permeate flux with increasing voltage supply. For PECM process at 1.0 V, its NOMs removal was 1.2 or 1.7 times higher than that of filtration with UV irradiation or filtration alone, and its stable permeate flux was 1.3 or 3 times higher than that of filtration with UV irradiation or filtration alone. Moreover, the PECM process exhibited special advantage in removing organic chemicals (e.g., Rhodamine B), which displayed 1.3 or 3 times higher removal than that of filtration with UV irradiation or filtration alone.

Staying Tight: Plasmodesmal Membrane Contact Sites and the Control of Cell-to-Cell Connectivity in Plants.

Science.gov (United States)

Tilsner, Jens; Nicolas, William; Rosado, Abel; Bayer, Emmanuelle M

2016-04-29

Multicellularity differs in plants and animals in that the cytoplasm, plasma membrane, and endomembrane of plants are connected between cells through plasmodesmal pores. Plasmodesmata (PDs) are essential for plant life and serve as conduits for the transport of proteins, small RNAs, hormones, and metabolites during developmental and defense signaling. They are also the only pathways available for viruses to spread within plant hosts. The membrane organization of PDs is unique, characterized by the close apposition of the endoplasmic reticulum and the plasma membrane and spoke-like filamentous structures linking the two membranes, which define PDs as membrane contact sites (MCSs). This specialized membrane arrangement is likely critical for PD function. Here, we review how PDs govern developmental and defensive signaling in plants, compare them with other types of MCSs, and discuss in detail the potential functional significance of the MCS nature of PDs.

Application of dynamic membranes in anaerobic membranes in anaerobic membrane bioreactor systems

NARCIS (Netherlands)

Erşahin, M.E.

2015-01-01

Anaerobic membrane bioreactors (AnMBRs) physically ensure biomass retention by the application of a membrane filtration process. With growing application experiences from aerobic membrane bioreactors (MBRs), the combination of membrane and anaerobic processes has received much attention and become

The role of hydrophobic interactions in positioning of peripheral proteins in membranes

Directory of Open Access Journals (Sweden)

Lomize Mikhail A

2007-06-01

Full Text Available Abstract Background Three-dimensional (3D structures of numerous peripheral membrane proteins have been determined. Biological activity, stability, and conformations of these proteins depend on their spatial positions with respect to the lipid bilayer. However, these positions are usually undetermined. Results We report the first large-scale computational study of monotopic/peripheral proteins with known 3D structures. The optimal translational and rotational positions of 476 proteins are determined by minimizing energy of protein transfer from water to the lipid bilayer, which is approximated by a hydrocarbon slab with a decadiene-like polarity and interfacial regions characterized by water-permeation profiles. Predicted membrane-binding sites, protein tilt angles and membrane penetration depths are consistent with spin-labeling, chemical modification, fluorescence, NMR, mutagenesis, and other experimental studies of 53 peripheral proteins and peptides. Experimental membrane binding affinities of peripheral proteins were reproduced in cases that did not involve a helix-coil transition, specific binding of lipids, or a predominantly electrostatic association. Coordinates of all examined peripheral proteins and peptides with the calculated hydrophobic membrane boundaries, subcellular localization, topology, structural classification, and experimental references are available through the Orientations of Proteins in Membranes (OPM database. Conclusion Positions of diverse peripheral proteins and peptides in the lipid bilayer can be accurately predicted using their 3D structures that represent a proper membrane-bound conformation and oligomeric state, and have membrane binding elements present. The success of the implicit solvation model suggests that hydrophobic interactions are usually sufficient to determine the spatial position of a protein in the membrane, even when electrostatic interactions or specific binding of lipids are substantial. Our

A conserved signaling network monitors delivery of sphingolipids to the plasma membrane in budding yeast.

Science.gov (United States)

Clarke, Jesse; Dephoure, Noah; Horecka, Ira; Gygi, Steven; Kellogg, Douglas

2017-10-01

In budding yeast, cell cycle progression and ribosome biogenesis are dependent on plasma membrane growth, which ensures that events of cell growth are coordinated with each other and with the cell cycle. However, the signals that link the cell cycle and ribosome biogenesis to membrane growth are poorly understood. Here we used proteome-wide mass spectrometry to systematically discover signals associated with membrane growth. The results suggest that membrane trafficking events required for membrane growth generate sphingolipid-dependent signals. A conserved signaling network appears to play an essential role in signaling by responding to delivery of sphingolipids to the plasma membrane. In addition, sphingolipid-dependent signals control phosphorylation of protein kinase C (Pkc1), which plays an essential role in the pathways that link the cell cycle and ribosome biogenesis to membrane growth. Together these discoveries provide new clues as to how growth--dependent signals control cell growth and the cell cycle. © 2017 Clarke et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Roles of membrane trafficking in plant cell wall dynamics

Directory of Open Access Journals (Sweden)

Kazuo eEbine

2015-10-01

Full Text Available The cell wall is one of the characteristic components of plant cells. The cell wall composition differs among cell types and is modified in response to various environmental conditions. To properly generate and modify the cell wall, many proteins are transported to the plasma membrane or extracellular space through membrane trafficking, which is one of the key protein transport mechanisms in eukaryotic cells. Given the diverse composition and functions of the cell wall in plants, the transport of the cell wall components and proteins that are involved in cell wall-related events could be specialized for each cell type, i.e., the machinery for cell wall biogenesis, modification, and maintenance could be transported via different trafficking pathways. In this review, we summarize the recent progress in the current understanding of the roles and mechanisms of membrane trafficking in plant cells and focus on the biogenesis and regulation of the cell wall.

Alpha detection in pipes using an inverting membrane scintillator

Energy Technology Data Exchange (ETDEWEB)

Kendrick, D.T.; Cremer, C.D.; Lowry, W. [Science and Engineering Associates, Inc., Albuquerque, NM (United States)] [and others

1995-10-01

Characterization of surface alpha emitting contamination inside enclosed spaces such as piping systems presents an interesting radiological measurement challenge. Detection of these alpha particles from the exterior of the pipe is impossible since the alpha particles are completely absorbed by the pipe wall. Traditional survey techniques, using hand-held instruments, simply can not be used effectively inside pipes. Science and Engineering Associates, Inc. is currently developing an enhancement to its Pipe Explorer{trademark} system that will address this challenge. The Pipe Explorer{trademark} uses a unique sensor deployment method where an inverted tubular membrane is propagated through complex pipe runs via air pressure. The inversion process causes the membrane to fold out against the pipe wall, such that no part of the membrane drags along the pipe wall. This deployment methodology has been successfully demonstrated at several DOE sites to transport specially designed beta and gamma, scintillation detectors into pipes ranging in length up to 250 ft.

The effectiveness of the developed program of 10-13 years girls' coordinative abilities who are going in for calisthenics.

Directory of Open Access Journals (Sweden)

Belokopitova G. A.

2011-04-01

Full Text Available It's developed and practically based the program on developing coordinative abilities according to the age group of 10-13 years old gymnastics. This program is for special stage of training and it is aimed for developing coordinating abilities connected to individual-psychological peculiarities of girls going for gymnastics. It was shown that sport result of 10-13 years girls' influences on index of psycho-moving futures - abilities for correction of their actions to free mobilization and moving coordination during performing fast work. It can be explained that index which is being expected shows the set of time-hour moves and allows evaluating gymnasts moves.

Provincial Coordination and Inter-Institutional Collaboration in British Columbia's College, University College and Institute System. Monograph Series.

Science.gov (United States)

Gaber, Devron

This document addresses a study that aimed to better understand the historical development of British Columbia community college, university college, and institute system with special attention given to recent changes in inter-institutional collaboration in relation to provincial coordination. The study also addresses centralization and…

Modal radiation patterns of baffled circular plates and membranes.

Science.gov (United States)

Christiansen, Thomas Lehrmann; Hansen, Ole; Thomsen, Erik Vilain; Jensen, Jørgen Arendt

2014-05-01

The far field velocity potential and radiation pattern of baffled circular plates and membranes are found analytically using the full set of modal velocity profiles derived from the corresponding equation of motion. The derivation is valid for a plate or membrane subjected to an external excitation force, which is used as a sound receiver in any medium or as a sound transmitter in a gaseous medium. A general, concise expression is given for the radiation pattern of any mode of the membrane and the plate with arbitrary boundary conditions. Specific solutions are given for the four special cases of a plate with clamped, simply supported, and free edge boundary conditions as well as for the membrane. For all non-axisymmetric modes, the velocity potential along the axis of the radiator is found to be strictly zero. In the long wavelength limit, the radiation pattern of all axisymmetric modes approaches that of a monopole, while the non-axisymmetric modes exhibit multipole behavior. Numerical results are also given, demonstrating the implications of having non-axisymmetric excitation using both a point excitation with varying eccentricity and a homogeneous excitation acting on half of the circular radiator.

Bio-Mimetic Sensors Based on Molecularly Imprinted Membranes

Directory of Open Access Journals (Sweden)

Catia Algieri

2014-07-01

Full Text Available An important challenge for scientific research is the production of artificial systems able to mimic the recognition mechanisms occurring at the molecular level in living systems. A valid contribution in this direction resulted from the development of molecular imprinting. By means of this technology, selective molecular recognition sites are introduced in a polymer, thus conferring it bio-mimetic properties. The potential applications of these systems include affinity separations, medical diagnostics, drug delivery, catalysis, etc. Recently, bio-sensing systems using molecularly imprinted membranes, a special form of imprinted polymers, have received the attention of scientists in various fields. In these systems imprinted membranes are used as bio-mimetic recognition elements which are integrated with a transducer component. The direct and rapid determination of an interaction between the recognition element and the target analyte (template was an encouraging factor for the development of such systems as alternatives to traditional bio-assay methods. Due to their high stability, sensitivity and specificity, bio-mimetic sensors-based membranes are used for environmental, food, and clinical uses. This review deals with the development of molecularly imprinted polymers and their different preparation methods. Referring to the last decades, the application of these membranes as bio-mimetic sensor devices will be also reported.

Review of Membrane Oxygen Enrichment for Efficient Combustion

Science.gov (United States)

Ariono, Danu; Kusuma Wardani, Anita

2017-07-01

Oxygen enrichment from air is a simple way of increasing the efficiency of combustion process, as in oxy-combustion. Oxy-combustion has become one of the most attracting combustion technologies because of its potential to address both pollutant reduction and CO2 capture. In oxy-combustion, the fuel and recycled flue gas are combusted with oxygen enriched air (OEA). By using OEA, many benefits can be obtained, such as increasing available heat, improving ignition characteristics, flue gas reduction, increasing productivity, energy efficiency, turndown ratio, and flame stability. Membrane-based gas separation for OEA production becomes an attractive technology over the conventional technology due to the some advantages, including low capital cost, low energy consumption, compact size, and modularity. A single pass through membrane usually can enrich O2 concentration in the air up to 35% and a 50% concentration can be achieved with a double pass of membrane. The use of OEA in the combustion process eliminates the presence of nitrogen in the flue gas. Hence, the flue gas is mainly composed of CO2 and condensable water that can be easily separated. This paper gives an overview of oxy-combustion with membrane technology for oxygen enrichment process. Special attention is given to OEA production and the effect of OEA to the efficiency of combustion.

Bio-Mimetic Sensors Based on Molecularly Imprinted Membranes

Science.gov (United States)

Algieri, Catia; Drioli, Enrico; Guzzo, Laura; Donato, Laura

2014-01-01

An important challenge for scientific research is the production of artificial systems able to mimic the recognition mechanisms occurring at the molecular level in living systems. A valid contribution in this direction resulted from the development of molecular imprinting. By means of this technology, selective molecular recognition sites are introduced in a polymer, thus conferring it bio-mimetic properties. The potential applications of these systems include affinity separations, medical diagnostics, drug delivery, catalysis, etc. Recently, bio-sensing systems using molecularly imprinted membranes, a special form of imprinted polymers, have received the attention of scientists in various fields. In these systems imprinted membranes are used as bio-mimetic recognition elements which are integrated with a transducer component. The direct and rapid determination of an interaction between the recognition element and the target analyte (template) was an encouraging factor for the development of such systems as alternatives to traditional bio-assay methods. Due to their high stability, sensitivity and specificity, bio-mimetic sensors-based membranes are used for environmental, food, and clinical uses. This review deals with the development of molecularly imprinted polymers and their different preparation methods. Referring to the last decades, the application of these membranes as bio-mimetic sensor devices will be also reported. PMID:25196110

Effect of ionizing radiations of lymphocyte membranes. Part of a coordinated programme on cell membrane probes as biological indicators in radiation accidents

International Nuclear Information System (INIS)

Ojeda, S.F.

1981-06-01

A study of the effects of low doses of irradiation on membrane receptors of lymphoid cells indicated that doses as low as 10 rads induced detectable changes in the antigen receptors of cell surfaces. Lymphoid cells from mice or rabbit lymph nodes, or circulating lymphocytes from human volunteers were irradiated and studied for their ability to bind antisera against the IgG membrane receptors. The isolated lymphoid cells were x-irradiated, and tested versus non-irradiated controls. They were incubated at 37 0 C for different times, and IgG-positive cells stained by the direct or indirect immunofluorescence technique. The percentage of IgG-positive cells was reduced by low-dose irradiation, and proved dose -and temperature-dependent. The disappearance phenomenon depends on the microtubular structure, metabolic energy, and levels of C-AMP. Only the reappearance phase is temperature-dependent and not affected by the drugs tested. The phenomenon is dose-rate dependent, showing greater sensitivity at lower dose/rates. Experiments using anti-Fc and anti-Fab portions of the surface molecule, appear to confirm a partial internatlization of the surface molecule as cause (at least in rabbit cells). Similar experiments with human cells did not show a differential effect. Human T-cells and FC receptors of Mast cells did, however, indicate that these surface molecules are also modified by irradiation

Extracellular membrane vesicles in blood products-biology and clinical relevance

Directory of Open Access Journals (Sweden)

Emilija Krstova Krajnc

2016-01-01

Full Text Available Extracellular membrane vesicles are fragments shed from plasma membranes off all cell types that are undergoing apoptosis or are being subjected to various types of stimulation or stress.  Even in the process of programmed cell death (apoptosis, cell fall apart of varying size vesicles. They expose phosphatidylserine (PS on the outer leaflet of their membrane, and bear surface membrane antigens reflecting their cellular origin. Extracellular membrane vesicles have been isolated from many types of biological fluids, including serum, cerebrospinal fluid, urine, saliva, tears and conditioned culture medium. Flow cytometry is one of the many different methodological approaches that have been used to analyze EMVs. The method attempts to characterize the EMVs cellular origin, size, population, number, and structure. EMVs are present and accumulate in blood products (erythrocytes, platelets as well as in fresh frozen plasma during storage. The aim of this review is to highlight the importance of extracellular vesicles as a cell-to-cell communication system and the role in the pathogenesis of different diseases. Special emphasis will be given to the implication of extracellular membrane vesicles in blood products and their clinical relevance. Although our understanding of the role of  EMVs in disease is far from comprehensive, they display promise as biomarkers for different diseases in the future and also as a marker of quality and safety in the quality control of blood products.

Differential subcellular membrane recruitment of Src may specify its downstream signalling

International Nuclear Information System (INIS)

Diesbach, Philippe de; Medts, Thierry; Carpentier, Sarah; D'Auria, Ludovic; Van Der Smissen, Patrick; Platek, Anna; Mettlen, Marcel; Caplanusi, Adrian; Hove, Marie-France van den; Tyteca, Donatienne; Courtoy, Pierre J.

2008-01-01

Most Src family members are diacylated and constitutively associate with membrane 'lipid rafts' that coordinate signalling. Whether the monoacylated Src, frequently hyperactive in carcinomas, also localizes at 'rafts' remains controversial. Using polarized MDCK cells expressing the thermosensitive v-Src/tsLA31 variant, we here addressed how Src tyrosine-kinase activation may impact on its (i) membrane recruitment, in particular to 'lipid rafts'; (ii) subcellular localization; and (iii) signalling. The kinetics of Src-kinase thermoactivation correlated with its recruitment from the cytosol to sedimentable membranes where Src largely resisted solubilisation by non-ionic detergents at 4 deg. C and floated into sucrose density gradients like caveolin-1 and flotillin-2, i.e. 'lipid rafts'. By immunofluorescence, activated Src showed a dual localization, at apical endosomes/macropinosomes and at the apical plasma membrane. The plasma membrane Src pool did not colocalize with caveolin-1 and flotillin-2, but extensively overlapped GM1 labelling by cholera toxin. Severe (∼ 70%) cholesterol extraction with methyl-β-cyclodextrin (MβCD) did not abolish 'rafts' floatation, but strongly decreased Src association with floating 'rafts' and abolished its localization at the apical plasma membrane. Src activation independently activated first the MAP-kinase - ERK1/2 pathway, then the PI3-kinase - Akt pathway. MAP-kinase - ERK1/2 activation was insensitive to MβCD, which suppressed Akt phosphorylation and apical endocytosis induced by Src, both depending on the PI3-kinase pathway. We therefore suggest that activated Src is recruited at two membrane compartments, allowing differential signalling, first via ERK1/2 at 'non-raft' domains on endosomes, then via PI3-kinase-Akt on a distinct set of 'rafts' at the apical plasma membrane. Whether this model is applicable to c-Src remains to be examined

Coordinate measuring machines

DEFF Research Database (Denmark)

De Chiffre, Leonardo

This document is used in connection with three exercises of 2 hours duration as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The exercises concern three aspects of coordinate measuring: 1) Measuring and verification of tolerances on coordinate measuring machines, 2) Traceabilit...... and uncertainty during coordinate measurements, 3) Digitalisation and Reverse Engineering. This document contains a short description of each step in the exercise and schemes with room for taking notes of the results.......This document is used in connection with three exercises of 2 hours duration as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The exercises concern three aspects of coordinate measuring: 1) Measuring and verification of tolerances on coordinate measuring machines, 2) Traceability...

Joint Coordinating Committee on environmental restoration and waste management (JCCEM) support, technology transfer, and special projects

International Nuclear Information System (INIS)

Edgar, D.E.

1993-01-01

Argonne National Laboratory (ANL) assisted in identifying and evaluating foreign technologies to meet EM needs; supported the evaluation, removal, and/or revision of barriers to international technology and information transfer/exchange; facilitated the integration and coordination of U.S. government international environmental restoration and waste management activities; and enhanced U.S. industry's competitiveness in the international environmental technology market

Nuclear Safety Co-Ordination within Oak Ridge Operations Facilities

Energy Technology Data Exchange (ETDEWEB)

Johnson, W. A.; Pryor, W. A. [Research and Development Division, United States Atomic Energy Commission, Oak Ridge, TN (United States)

1966-05-15

The Oak Ridge Operations Office of the USAEC has within its jurisdiction multiple contractors and facilities for research and for the production of fissile materials for the atomic energy programme. Among these facilities are gaseous diffusion plants for the production of {sup 235}U-enriched uranium hexafluoride, plants for the fabrication of special components and fuel for research and production reactors, and laboratories for pilot plant studies and basic research in nuclear technology. One research laboratory is also actively engaged in criticality experimental programmes and has been a major contributor of criticality data for safety applications. These diversified programmes include the processing, fabrication and transport of practically all forms and isotopic enrichments of uranium in quantities commensurate with both laboratory and volume production requirements. Consequently, adequate nuclear safety control with reasonable economy for operations of this magnitude demands not only co-ordination and liaison between contractor and USAEC staffs, but a continuing reappraisal of safety applications in light of the most advanced information. This report outlines the role of the Oak Ridge Operations Office in these pursuits and describes as examples some specific problems in which this office co-ordinated actions necessary for their resolution. Other examples are given of parametric and procedural applications in plant processes and fissile shipments emphasizing the use of recent experimental or calculated data. These examples involve the use of mass and geometric variables, neutron absorbers and moderation control. Departures from limits specified in existing nuclear safety guides are made to advantage in light of new data, special equipment design, contingencies and acceptable risks. (author)

Smart membranes for monitoring membrane based desalination processes

KAUST Repository

Laleg-Kirati, Taous-Meriem

2017-10-12

Various examples are related to smart membranes for monitoring membrane based process such as, e.g., membrane distillation processes. In one example, a membrane, includes a porous surface and a plurality of sensors (e.g., temperature, flow and/or impedance sensors) mounted on the porous surface. In another example, a membrane distillation (MD) process includes the membrane. Processing circuitry can be configured to monitor outputs of the plurality of sensors. The monitored outputs can be used to determine membrane degradation, membrane fouling, or to provide an indication of membrane replacement or cleaning. The sensors can also provide temperatures or temperature differentials across the porous surface, which can be used to improve modeling or control the MD process.

Selective isolation of cationic amino acids and peptides by electro-membrane filtration

NARCIS (Netherlands)

Bargeman, Gerrald; Dohmen-Speelmans, Monique; Recio, Isidra; Timmer, Martin; van der Horst, Caroline

2000-01-01

In the food industry there is a clear trend towards the production of speciality products with a high added value. Electro-membrane filtration (EMF) can be used to separate and concentrate these products from complex solutions. With EMF, lysine was separated from a model solution and a protein

Recent advances on polymeric membranes for membrane reactors

KAUST Repository

Buonomenna, M. G.; Choi, Seung Hak

2012-01-01

. The successful use of membranes in membrane reactors is primary the result of two developments concerning: (i) membrane materials and (ii) membrane structures. The selection of a suited material and preparation technique depends on the application the membrane

Introduction to the Special Issue on Marketing and Operations Management Interfaces and Coordination

OpenAIRE

Teck H. Ho; Christopher S. Tang

2004-01-01

This special issue, by addressing problems surrounding marketing and operations management, depicts state-of-the-art approaches, methodologies, and insights to improve a firm's or supply chain's overall performance. Top scholars in the field address many of the ways in which companies can synchronize their marketing and operations departments or their supply chain partners to improve competitiveness and profit. The information in this issue should be of interest both to academics and managers...

Recent advances on polymeric membranes for membrane reactors

KAUST Repository

Buonomenna, M. G.

2012-06-24

Membrane reactors are generally applied in high temperature reactions (>400 °C). In the field of fine chemical synthesis, however, much milder conditions are generally applicable and polymeric membranes were applied without their damage. The successful use of membranes in membrane reactors is primary the result of two developments concerning: (i) membrane materials and (ii) membrane structures. The selection of a suited material and preparation technique depends on the application the membrane is to be used in. In this chapter a review of up to date literature about polymers and configuration catalyst/ membranes used in some recent polymeric membrane reactors is given. The new emerging concept of polymeric microcapsules as catalytic microreactors has been proposed. © 2012 Bentham Science Publishers. All rights reserved.

Coordinated safeguards for materials management in a mixed-oxide fuel facility

International Nuclear Information System (INIS)

Shipley, J.P.; Cobb, D.D.; Dietz, R.J.; Evans, M.L.; Schelonka, E.P.; Smith, D.B.; Walton, R.B.

1977-02-01

A coordinated safeguards system is described for safeguarding strategic quantities of special nuclear materials in mixed-oxide recycle fuel fabrication facilities. The safeguards system is compatible with industrial process requirements and combines maximum effectiveness consistent with modest cost and minimal process interference. It is based on unit process accounting using a combination of conventional and state-of-the-art NDA measurement techniques. The effectiveness of the system against single and multiple thefts is evaluated using computer modeling and simulation techniques

Coordinated safeguards for materials management in a mixed-oxide fuel facility

Energy Technology Data Exchange (ETDEWEB)

Shipley, J.P.; Cobb, D.D.; Dietz, R.J.; Evans, M.L.; Schelonka, E.P.; Smith, D.B.; Walton, R.B.

1977-02-01

A coordinated safeguards system is described for safeguarding strategic quantities of special nuclear materials in mixed-oxide recycle fuel fabrication facilities. The safeguards system is compatible with industrial process requirements and combines maximum effectiveness consistent with modest cost and minimal process interference. It is based on unit process accounting using a combination of conventional and state-of-the-art NDA measurement techniques. The effectiveness of the system against single and multiple thefts is evaluated using computer modeling and simulation techniques.

Scale-Up Design Analysis and Modelling of Cobalt Oxide Silica Membrane Module for Hydrogen Processing

Directory of Open Access Journals (Sweden)

Guozhao Ji

2013-08-01

Full Text Available This work shows the application of a validated mathematical model for gas permeation at high temperatures focusing on demonstrated scale-up design for H2 processing. The model considered the driving force variation with spatial coordinates and the mass transfer across the molecular sieve cobalt oxide silica membrane to predict the separation performance. The model was used to study the process of H2 separation at 500 °C in single and multi-tube membrane modules. Parameters of interest included the H2 purity in the permeate stream, H2 recovery and H2 yield as a function of the membrane length, number of tubes in a membrane module, space velocity and H2 feed molar fraction. For a single tubular membrane, increasing the length of a membrane tube led to higher H2 yield and H2 recovery, owing to the increase of the membrane area. However, the H2 purity decreased as H2 fraction was depleted, thus reducing the driving force for H2 permeation. By keeping the membrane length constant in a multi-tube arrangement, the H2 yield and H2 recovery increase was attributed to the higher membrane area, but the H2 purity was again compromised. Increasing the space velocity avoided the reduction of H2 purity and still delivered higher H2 yield and H2 recovery than in a single membrane arrangement. Essentially, if the membrane surface is too large, the driving force becomes lower at the expense of H2 purity. In this case, the membrane module is over designed. Hence, maintaining a driving force is of utmost importance to deliver the functionality of process separation.

Conversion of hydrophilic SiOC nanofibrous membrane to robust hydrophobic materials by introducing palladium

Science.gov (United States)

Wu, Nan; Wan, Lynn Yuqin; Wang, Yingde; Ko, Frank

2017-12-01

Hydrophobic ceramic nanofibrous membranes have wide applications in the fields of high-temperature filters, oil/water separators, catalyst supports and membrane reactors, for their water repellency property, self-cleaning capability, good environmental stability and long life span. In this work, we fabricated an inherently hydrophobic ceramic nanofiber membrane without any surface modification through pyrolysis of electrospun polycarbosilane nanofibers. The hydrophobicity was introduced by the hierarchical microstructure formed on the surface of the nanofibers and the special surface composition by the addition of trace amounts of palladium. Furthermore, the flexible ceramic mats demonstrated robust chemical resistance properties with consistent hydrophobicity over the entire pH value range and effective water-in-oil emulsion separation performance. Interestingly, a highly cohesive force was found between water droplet and the ceramic membranes, suggesting their great potentials in micro-liquid transportation. This work provides a new route for adjusting the composition of ceramic surface and flexible, recyclable and multifunctional ceramic fibrous membranes for utilization in harsh environments.

Organization of the ITER Co-ordinated Technical Activities International Team

International Nuclear Information System (INIS)

2001-01-01

At its meeting in Toronto on 7 November 2001, the ITER Co-ordinated Technical Activities (CTA) project board took note of the organizational arrangements for the CTA International Team at the Garching and Naka joint work sites. The organization chart of the team remains almost unchanged from that of the ITER Engineering Design Activities (EDA). However, there is no special division responsible for plasma and field control. Activities in plasma control will be taken over by the Physics Unit. This newsletter also includes the ITER CTA International Team structure

Support of Publication Costs, Atlantic Meridional Overturning Circulation Special Issue of Deep Sea Research II Journal

Energy Technology Data Exchange (ETDEWEB)

Amy Honchar

2012-11-12

The contribution of funds from DOE supported publication costs of a special issue of Deep Sea Research arising from presentations at the First U.S. Atlantic Meridional Overturning Circulation (AMOC) Meeting held 4-6 May, 2009 to review the US implementation plan and its coordination with other monitoring activities. The special issue includes a total of 16 papers, including publications from three DOE-supported investigators (ie Sevellec, F., and A.V. Fedorov; Hu et. al., and Wan et. al.,). The special issue addresses DOE interests in understanding and simulation/modeling of abrupt climate change.

Coordinated School Health and the Contribution of a District Wellness Coordinator

Science.gov (United States)

Westrich, Lisa; Sanchez, Monika; Strobel, Karen

2015-01-01

Background: A San Francisco Bay Area school health initiative was established in fall 2010 to improve wellness programs in 4 local school districts using the Coordinated School Health (CSH) model. This study examines the role of district-wide wellness coordinators and the ways in which they contribute to intentional coordination of health and…

Concerted regulation of retinal pigment epithelium basement membrane and barrier function by angiocrine factors.

Science.gov (United States)

Benedicto, Ignacio; Lehmann, Guillermo L; Ginsberg, Michael; Nolan, Daniel J; Bareja, Rohan; Elemento, Olivier; Salfati, Zelda; Alam, Nazia M; Prusky, Glen T; Llanos, Pierre; Rabbany, Sina Y; Maminishkis, Arvydas; Miller, Sheldon S; Rafii, Shahin; Rodriguez-Boulan, Enrique

2017-05-19

The outer blood-retina barrier is established through the coordinated terminal maturation of the retinal pigment epithelium (RPE), fenestrated choroid endothelial cells (ECs) and Bruch's membrane, a highly organized basement membrane that lies between both cell types. Here we study the contribution of choroid ECs to this process by comparing their gene expression profile before (P5) and after (P30) the critical postnatal period when mice acquire mature visual function. Transcriptome analyses show that expression of extracellular matrix-related genes changes dramatically over this period. Co-culture experiments support the existence of a novel regulatory pathway: ECs secrete factors that remodel RPE basement membrane, and integrin receptors sense these changes triggering Rho GTPase signals that modulate RPE tight junctions and enhance RPE barrier function. We anticipate our results will spawn a search for additional roles of choroid ECs in RPE physiology and disease.

Complexation-Induced Phase Separation: Preparation of Metal-Rich Polymeric Membranes

KAUST Repository

Villalobos Vazquez de la Parra, Luis Francisco

2017-08-01

The majority of state-of-the-art polymeric membranes for industrial or medical applications are fabricated by phase inversion. Complexation induced phase separation (CIPS)—a surprising variation of this well-known process—allows direct fabrication of hybrid membranes in existing facilities. In the CIPS process, a first step forms the thin metal-rich selective layer of the membrane, and a succeeding step the porous support. Precipitation of the selective layer takes place in the same solvent used to dissolve the polymer and is induced by a small concentration of metal ions. These ions form metal-coordination-based crosslinks leading to the formation of a solid skin floating on top of the liquid polymer film. A subsequent precipitation in a nonsolvent bath leads to the formation of the porous support structure. Forming the dense layer and porous support by different mechanisms while maintaining the simplicity of a phase inversion process, results in unprecedented control over the final structure of the membrane. The thickness and morphology of the dense layer as well as the porosity of the support can be controlled over a wide range by manipulating simple process parameters. CIPS facilitates control over (i) the thickness of the dense layer throughout several orders of magnitude—from less than 15 nm to more than 6 μm, (ii) the type and amount of metal ions loaded in the dense layer, (iii) the morphology of the membrane surface, and (iv) the porosity and structure of the support. The nature of the CIPS process facilitates a precise loading of a high concentration of metal ions that are located in only the top layer of the membrane. Moreover, these metal ions can be converted—during the membrane fabrication process—to nanoparticles or crystals. This simple method opens up fascinating possibilities for the fabrication of metal-rich polymeric membranes with a new set of properties. This dissertation describes the process in depth and explores promising

Tuning of Nafion® by HKUST-1 as coordination network to enhance proton conductivity for fuel cell applications

International Nuclear Information System (INIS)

Kim, Hee Jin; Talukdar, Krishan; Choi, Sang-June

2016-01-01

Metal-organic frameworks can be intentionally coordinated to achieve improved proton conductivity because they have highly ordered structures and modular nature that serve as a scaffold to anchor acidic groups and develop efficient proton transfer pathways for fuel cell application. Using the concept of a coordination network, the conductivity of Nafion ® was tuned by the incorporation of HKUST-1. It has Cu II –paddle wheel type nodes and 1,3,5-benzenetricarboxylate struts, feature accessible sites that provides an improved protonic channel depending on the water content. In spite of the fact that HKUST-1 is neutral, coordinated water molecules are contributed adequately acidic by Cu II to supply protons to enhance proton conductivity. Water molecules play a vital part in transfer of proton as conducting media and serve as triggers to change proton conductivity through reforming hydrogen bonding networks by water adsorption/desorption process. Increased ion exchange capacity and proton conductivity with lower water uptake of the H 3 PO 4 -doped material, and improved thermal stability (as confirmed by thermogravimetric analysis) were achieved. The structure of HKUST-1 was confirmed via field emission scanning electron microscopy and X-ray diffraction, while the porosity and adsorption desorption capacity were characterized by porosity analysis. Graphical abstract: The H 3 PO 4 -doped HKUST-1/Nafion® composite membrane is demonstrated to be a promising material based on its proton conductivity. HKUST-1 has an average particle diameter of around 15–20 µm. The proton conductivity, IEC values, and the thermal stability of the 2.5 wt% HKUST-1/Nafion® composite membrane suggest that HKUST-1 may be a promising candidate as a proton-conductive material in the polymer electrolyte fuel cell membrane due to its reasonable proton passageway, favorable surface area, lower water uptake with the higher IEC, and proton conductivity of the H 3 PO 4 -doped material and

Syntheses, Characterization, Resolution, and Biological Studies of Coordination Compounds of Aspartic Acid and Glycine

Science.gov (United States)

Akinkunmi, Ezekiel; Ojo, Isaac; Adebajo, Clement; Isabirye, David

2017-01-01

Enantiomerically enriched coordination compounds of aspartic acid and racemic mixtures of coordination compounds of glycine metal-ligand ratio 1 : 3 were synthesized and characterized using infrared and UV-Vis spectrophotometric techniques and magnetic susceptibility measurements. Five of the complexes were resolved using (+)-cis-dichlorobis(ethylenediamine)cobalt(III) chloride, (+)-bis(glycinato)(1,10-phenanthroline)cobalt(III) chloride, and (+)-tris(1,10-phenanthroline)nickel(II) chloride as resolving agents. The antimicrobial and cytotoxic activities of these complexes were then determined. The results obtained indicated that aspartic acid and glycine coordinated in a bidentate fashion. The enantiomeric purity of the compounds was in the range of 22.10–32.10%, with (+)-cis-dichlorobis(ethylenediamine)cobalt(III) complex as the more efficient resolving agent. The resolved complexes exhibited better activity in some cases compared to the parent complexes for both biological activities. It was therefore inferred that although the increase in the lipophilicity of the complexes may assist in the permeability of the complexes through the cell membrane of the pathogens, the enantiomeric purity of the complexes is also of importance in their activity as antimicrobial and cytotoxic agents. PMID:28293149

Recent progress on lipid lateral heterogeneity in plasma membranes: from rafts to submicrometric domains

Science.gov (United States)

Carquin, Mélanie; D'Auria, Ludovic; Pollet, Hélène; Bongarzone, Ernesto R.; Tyteca, Donatienne

2016-01-01

The concept of transient nanometric domains known as lipid rafts has brought interest to reassess the validity of the Singer-Nicholson model of a fluid bilayer for cell membranes. However, this new view is still insufficient to explain the cellular control of surface lipid diversity or membrane deformability. During the past decade, the hypothesis that some lipids form large (submicrometric/mesoscale vs nanometric rafts) and stable (> min vs sec) membrane domains has emerged, largely based on indirect methods. Morphological evidence for stable submicrometric lipid domains, well-accepted for artificial and highly specialized biological membranes, was further reported for a variety of living cells from prokaryotes to yeast and mammalian cells. However, results remained questioned based on limitations of available fluorescent tools, use of poor lipid fixatives, and imaging artifacts due to non-resolved membrane projections. In this review, we will discuss recent evidence generated using powerful and innovative approaches such as lipid-specific toxin fragments that support the existence of submicrometric domains. We will integrate documented mechanisms involved in the formation and maintenance of these domains, and provide a perspective on their relevance on membrane deformability and regulation of membrane protein distribution. PMID:26738447

Connections: Developing Skills for the Family of the Young Special Child, 0-5. [and] A Coordinators Guide.

Science.gov (United States)

Mendoza, Jeanne; And Others

The program is intended to increase skills in parents of young handicapped children. The coordinator's guide traces the background and development of the parent involvement materials, presents suggestions for workshop planning and actual implementation, and discusses training approaches for developing small group facilitation skills. The companion…

Two-dimensional materials for novel liquid separation membranes

Science.gov (United States)

Ying, Yulong; Yang, Yefeng; Ying, Wen; Peng, Xinsheng

2016-08-01

Demand for a perfect molecular-level separation membrane with ultrafast permeation and a robust mechanical property for any kind of species to be blocked in water purification and desalination is urgent. In recent years, due to their intrinsic characteristics, such as a unique mono-atom thick structure, outstanding mechanical strength and excellent flexibility, as well as facile and large-scale production, graphene and its large family of two-dimensional (2D) materials are regarded as ideal membrane materials for ultrafast molecular separation. A perfect separation membrane should be as thin as possible to maximize its flux, mechanically robust and without failure even if under high loading pressure, and have a narrow nanochannel size distribution to guarantee its selectivity. The latest breakthrough in 2D material-based membranes will be reviewed both in theories and experiments, including their current state-of-the-art fabrication, structure design, simulation and applications. Special attention will be focused on the designs and strategies employed to control microstructures to enhance permeation and selectivity for liquid separation. In addition, critical views on the separation mechanism within two-dimensional material-based membranes will be provided based on a discussion of the effects of intrinsic defects during growth, predefined nanopores and nanochannels during subsequent fabrication processes, the interlayer spacing of stacking 2D material flakes and the surface charge or functional groups. Furthermore, we will summarize the significant progress of these 2D material-based membranes for liquid separation in nanofiltration/ultrafiltration and pervaporation. Lastly, we will recall issues requiring attention, and discuss existing questionable conclusions in some articles and emerging challenges. This review will serve as a valuable platform to provide a compact source of relevant and timely information about the development of 2D material-based membranes as

Two-dimensional materials for novel liquid separation membranes.

Science.gov (United States)

Ying, Yulong; Yang, Yefeng; Ying, Wen; Peng, Xinsheng

2016-08-19

Demand for a perfect molecular-level separation membrane with ultrafast permeation and a robust mechanical property for any kind of species to be blocked in water purification and desalination is urgent. In recent years, due to their intrinsic characteristics, such as a unique mono-atom thick structure, outstanding mechanical strength and excellent flexibility, as well as facile and large-scale production, graphene and its large family of two-dimensional (2D) materials are regarded as ideal membrane materials for ultrafast molecular separation. A perfect separation membrane should be as thin as possible to maximize its flux, mechanically robust and without failure even if under high loading pressure, and have a narrow nanochannel size distribution to guarantee its selectivity. The latest breakthrough in 2D material-based membranes will be reviewed both in theories and experiments, including their current state-of-the-art fabrication, structure design, simulation and applications. Special attention will be focused on the designs and strategies employed to control microstructures to enhance permeation and selectivity for liquid separation. In addition, critical views on the separation mechanism within two-dimensional material-based membranes will be provided based on a discussion of the effects of intrinsic defects during growth, predefined nanopores and nanochannels during subsequent fabrication processes, the interlayer spacing of stacking 2D material flakes and the surface charge or functional groups. Furthermore, we will summarize the significant progress of these 2D material-based membranes for liquid separation in nanofiltration/ultrafiltration and pervaporation. Lastly, we will recall issues requiring attention, and discuss existing questionable conclusions in some articles and emerging challenges. This review will serve as a valuable platform to provide a compact source of relevant and timely information about the development of 2D material-based membranes as

Fraction Reduction in Membrane Systems

Directory of Open Access Journals (Sweden)

Ping Guo

2014-01-01

Full Text Available Fraction reduction is a basic computation for rational numbers. P system is a new computing model, while the current methods for fraction reductions are not available in these systems. In this paper, we propose a method of fraction reduction and discuss how to carry it out in cell-like P systems with the membrane structure and the rules with priority designed. During the application of fraction reduction rules, synchronization is guaranteed by arranging some special objects in these rules. Our work contributes to performing the rational computation in P systems since the rational operands can be given in the form of fraction.

Plant membranes a biophysical approach to structure, development and senescence

CERN Document Server

Leshem, Ya’Acov Y

1992-01-01

The plasma membrane is at once the window through which the cell senses the environment and the portal through which the environment influences the structure and activities of the cell. Its importance in cellular physiology can thus hardly be overestimated, since constant flow of materials between cell and environment is essential to the well-being of any biological system. The nature of the materials mov­ ing into the cell is also critical, since some substances are required for maintenance and growth, while others, because of their toxicity, must either be rigorously excluded or permitted to enter only after chemical alteration. Such alteration frequently permits the compounds to be sequestered in special cellular compartments having different types of membranes. This type of homogeneity, plus the fact that the wear and tear of transmembrane molecular traffic compels the system to be constantly monitored and repaired, means that the membrane system of any organism must be both structurally complex and dy­...

Membrane fouling mechanism of biofilm-membrane bioreactor (BF-MBR): Pore blocking model and membrane cleaning.

Science.gov (United States)

Zheng, Yi; Zhang, Wenxiang; Tang, Bing; Ding, Jie; Zheng, Yi; Zhang, Zhien

2018-02-01

Biofilm membrane bioreactor (BF-MBR) is considered as an important wastewater treatment technology that incorporates advantages of both biofilm and MBR process, as well as can alleviate membrane fouling, with respect to the conventional activated sludge MBR. But, to be efficient, it necessitates the establishment of proper methods for the assessment of membrane fouling. Four Hermia membrane blocking models were adopted to quantify and evaluate the membrane fouling of BF-MBR. The experiments were conducted with various operational conditions, including membrane types, agitation speeds and transmembrane pressure (TMP). Good agreement between cake formation model and experimental data was found, confirming the validity of the Hermia models for assessing the membrane fouling of BF-MBR and that cake layer deposits on membrane. Moreover, the influences of membrane types, agitation speeds and transmembrane pressure on the Hermia pore blocking coefficient of cake layer were investigated. In addition, the permeability recovery after membrane cleaning at various operational conditions was studied. This work confirms that, unlike conventional activated sludge MBR, BF-MBR possesses a low degree of membrane fouling and a higher membrane permeability recovery after cleaning. Copyright © 2017 Elsevier Ltd. All rights reserved.

Membrane fractions active in poliovirus RNA replication contain VPg precursor polypeptides

International Nuclear Information System (INIS)

Takegami, T.; Semler, B.L.; Anderson, C.W.; Wimmer, E.

1983-01-01

The poliovirus specific polypeptide P3-9 is of special interest for studies of viral RNA replication because it contains a hydrophobic region and, separated by only seven amino acids from that region, the amino acid sequence of the genome-linked protein VPg. Membraneous complexes of poliovirus-infected HeLa cells that contain poliovirus RNA replicating proteins have been analyzed for the presence of P3-9 by immunoprecipitation. Incubation of a membrane fraction rich in P3-9 with proteinase leaves the C-terminal 69 amino acids of P3-9 intact, an observation suggesting that this portion is protected by its association with the cellular membrane. These studies have also revealed two hitherto undescribed viral polypeptides consisting of amino acid sequences of the P2 andf P3 regions of the polyprotein. Sequence analysis by stepwise Edman degradation show that these proteins are 3b/9 (M/sub r/77,000) and X/9 (M/sub r/50,000). 3b/9 and X/9 are membrane bound and are turned over rapidly and may be direct precursors to proteins P2-X and P3-9 of the RNA replication complex. P2-X, a polypeptide void of hydrophobic amino acid sequences but also found associated with membranes, is rapidly degraded when the membraneous complex is treated with trypsin. It is speculated that P2-X is associated with membranes by its affinity to the N-terminus of P3-9

Membrane composition and dynamics: a target of bioactive virgin olive oil constituents.

Science.gov (United States)

Lopez, Sergio; Bermudez, Beatriz; Montserrat-de la Paz, Sergio; Jaramillo, Sara; Varela, Lourdes M; Ortega-Gomez, Almudena; Abia, Rocio; Muriana, Francisco J G

2014-06-01

The endogenous synthesis of lipids, which requires suitable dietary raw materials, is critical for the formation of membrane bilayers. In eukaryotic cells, phospholipids are the predominant membrane lipids and consist of hydrophobic acyl chains attached to a hydrophilic head group. The relative balance between saturated, monounsaturated, and polyunsaturated acyl chains is required for the organization and normal function of membranes. Virgin olive oil is the richest natural dietary source of the monounsaturated lipid oleic acid and is one of the key components of the healthy Mediterranean diet. Virgin olive oil also contains a unique constellation of many other lipophilic and amphipathic constituents whose health benefits are still being discovered. The focus of this review is the latest evidence regarding the impact of oleic acid and the minor constituents of virgin olive oil on the arrangement and behavior of lipid bilayers. We highlight the relevance of these interactions to the potential use of virgin olive oil in preserving the functional properties of membranes to maintain health and in modulating membrane functions that can be altered in several pathologies. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy. Copyright © 2014 Elsevier B.V. All rights reserved.

Consequences of C4 differentiation for chloroplast membrane proteomes in maize mesophyll and bundle sheath cells.

Science.gov (United States)

Majeran, Wojciech; Zybailov, Boris; Ytterberg, A Jimmy; Dunsmore, Jason; Sun, Qi; van Wijk, Klaas J

2008-09-01

Chloroplasts of maize leaves differentiate into specific bundle sheath (BS) and mesophyll (M) types to accommodate C(4) photosynthesis. Chloroplasts contain thylakoid and envelope membranes that contain the photosynthetic machineries and transporters but also proteins involved in e.g. protein homeostasis. These chloroplast membranes must be specialized within each cell type to accommodate C(4) photosynthesis and regulate metabolic fluxes and activities. This quantitative study determined the differentiated state of BS and M chloroplast thylakoid and envelope membrane proteomes and their oligomeric states using innovative gel-based and mass spectrometry-based protein quantifications. This included native gels, iTRAQ, and label-free quantification using an LTQ-Orbitrap. Subunits of Photosystems I and II, the cytochrome b(6)f, and ATP synthase complexes showed average BS/M accumulation ratios of 1.6, 0.45, 1.0, and 1.33, respectively, whereas ratios for the light-harvesting complex I and II families were 1.72 and 0.68, respectively. A 1000-kDa BS-specific NAD(P)H dehydrogenase complex with associated proteins of unknown function containing more than 15 proteins was observed; we speculate that this novel complex possibly functions in inorganic carbon concentration when carboxylation rates by ribulose-bisphosphate carboxylase/oxygenase are lower than decarboxylation rates by malic enzyme. Differential accumulation of thylakoid proteases (Egy and DegP), state transition kinases (STN7,8), and Photosystem I and II assembly factors was observed, suggesting that cell-specific photosynthetic electron transport depends on post-translational regulatory mechanisms. BS/M ratios for inner envelope transporters phosphoenolpyruvate/P(i) translocator, Dit1, Dit2, and Mex1 were determined and reflect metabolic fluxes in carbon metabolism. A wide variety of hundreds of other proteins showed differential BS/M accumulation. Mass spectral information and functional annotations are

Importance of coordination skills essential psychophysical demonstrated competencies as a military specialists

Directory of Open Access Journals (Sweden)

V.O. Lisowski

2013-12-01

Full Text Available The aim - to identify the role and importance of coordination abilities in the manifestation of professionally important qualities of psychophysical military experts. It is established that the exercise of general, special and specific coordination abilities provides the most efficient and reliable psychophysical military readiness and suitability to the successful solution of the tasks of combat mission. It is noted that a professionally-applied physical training future military specialist should focus on the development of a certain amount of knowledge and skills. Also - on the formation of professionally important psychophysical qualities that ensure a high degree of readiness of the military to successfully complete the tasks in extreme conditions. Set of system- level structural relationships of mental and physical indicators of the motor and functional fitness, mental processes, and psychomotor ability to control motor actions in different conditions of military occupation.

Special needs children with speech and hearing difficulties: prevalence and unmet needs.

Science.gov (United States)

Kenney, Mary Kay; Kogan, Michael D

2011-01-01

The purpose of this study was to establish prevalences and sociodemographic characteristics associated with parent-reported speech and hearing difficulties among children with special health care needs (CSHCN); determine unmet needs for therapy, hearing aids, and communication devices; and examine the association between unmet needs and resources such as health insurance, early intervention/special education, and a medical home. Data were analyzed for 300,910 children without special health care needs and 40,723 CSHCN from the 2005-2006 National Survey of Children with Special Health Care Needs. Prevalence, sociodemographic characteristics, and unmet needs for 7132 CSHCN with speech difficulties and 1982 CSHCN with hearing difficulties were assessed. Logistic regression was used to determine the associations between unmet needs for therapy or hearing/communication devices and resources for addressing needs for therapy, hearing, and communication aids. The parent-reported prevalence of speech difficulty among CSHCN in the general population was 2.9% and approximately 20% among all CSHCN, in contrast to the lower prevalence of hearing difficulty (0.7% and 5%, respectively). Relative unmet need was greatest for communication devices and least for hearing aids. The strongest association with reducing unmet needs was having a medical home, and the most significant aspect of medical home was having effective care coordination. Having a medical home is significantly associated with fewer unmet needs for therapy and hearing/communication devices among CSHCN with speech and hearing difficulties. Care coordination may constitute an important factor that allows the primary care provider to link with services that CSHCN with communication problems require. Published by Elsevier Inc.

Plasma membrane calcium ATPase 4 (PMCA4) co-ordinates calcium and nitric oxide signaling in regulating murine sperm functional activity.

Science.gov (United States)

Olli, Kristine E; Li, Kun; Galileo, Deni S; Martin-DeLeon, Patricia A

2018-01-01

Reduced sperm motility (asthenospermia) and resulting infertility arise from deletion of the Plasma Membrane Ca 2+ -ATPase 4 (Pmca4) gene which encodes the highly conserved Ca 2+ efflux pump, PMCA4. This is the major Ca 2+ clearance protein in murine sperm. Since the mechanism underlying asthenospermia in PMCA4's absence or reduced activity is unknown, we investigated if sperm PMCA4 negatively regulates nitric oxide synthases (NOSs) and when absent NO, peroxynitrite, and oxidative stress levels are increased. Using co-immunoprecipitation (Co-IP) and Fluorescence Resonance Energy Transfer (FRET), we show an association of PMCA4 with the NOSs in elevated cytosolic [Ca 2+ ] in capacitated and Ca 2+ ionophore-treated sperm and with neuronal (nNOS) at basal [Ca 2+ ] (ucapacitated sperm). FRET efficiencies for PMCA4-eNOS were 35% and 23% in capacitated and uncapacitated sperm, significantly (p < 0.01) different, with the molecules being <10 nm apart. For PMCA4-nNOS, this interaction was seen only for capacitated sperm where FRET efficiency was 24%, significantly (p < 0.05) higher than in uncapacitated sperm (6%). PMCA4 and the NOSs were identified as interacting partners in a quaternary complex that includes Caveolin1, which co-immunoprecipitated with eNOS in a Ca 2+ -dependent manner. In Pmca4 -/- sperm NOS activity was elevated twofold in capacitated/uncapacitated sperm (vs. wild-type), accompanied by a twofold increase in peroxynitrite levels and significantly (p < 0.001) increased numbers of apoptotic germ cells. The data support a quaternary complex model in which PMCA4 co-ordinates Ca 2+ and NO signaling to maintain motility, with increased NO levels resulting in asthenospermia in Pmca4 -/- males. They suggest the involvement of PMCA4 mutations in human asthenospermia, with diagnostic relevance. © 2017 Wiley Periodicals, Inc.

Membrane dynamics

DEFF Research Database (Denmark)

Bendix, Pól Martin

2015-01-01

Current topics include membrane-protein interactions with regard to membrane deformation or curvature sensing by BAR domains. Also, we study the dynamics of membrane tubes of both cells and simple model membrane tubes. Finally, we study membrane phase behavior which has important implications...... for the lateral organization of membranes as wells as for physical properties like bending, permeability and elasticity...

Variationally optimal selection of slow coordinates and reaction coordinates in macromolecular systems

Science.gov (United States)

Noe, Frank

To efficiently simulate and generate understanding from simulations of complex macromolecular systems, the concept of slow collective coordinates or reaction coordinates is of fundamental importance. Here we will introduce variational approaches to approximate the slow coordinates and the reaction coordinates between selected end-states given MD simulations of the macromolecular system and a (possibly large) basis set of candidate coordinates. We will then discuss how to select physically intuitive order paremeters that are good surrogates of this variationally optimal result. These result can be used in order to construct Markov state models or other models of the stationary and kinetics properties, in order to parametrize low-dimensional / coarse-grained model of the dynamics. Deutsche Forschungsgemeinschaft, European Research Council.

Inverse colloidal crystal membranes for hydrophobic interaction membrane chromatography.

Science.gov (United States)

Vu, Anh T; Wang, Xinying; Wickramasinghe, S Ranil; Yu, Bing; Yuan, Hua; Cong, Hailin; Luo, Yongli; Tang, Jianguo

2015-08-01

Hydrophobic interaction membrane chromatography has gained interest due to its excellent performance in the purification of humanized monoclonal antibodies. The membrane material used in hydrophobic interaction membrane chromatography has typically been commercially available polyvinylidene fluoride. In this contribution, newly developed inverse colloidal crystal membranes that have uniform pores, high porosity and, therefore, high surface area for protein binding are used as hydrophobic interaction membrane chromatography membranes for humanized monoclonal antibody immunoglobulin G purification. The capacity of the inverse colloidal crystal membranes developed here is up to ten times greater than commercially available polyvinylidene fluoride membranes with a similar pore size. This work highlights the importance of developing uniform pore size high porosity membranes in order to maximize the capacity of hydrophobic interaction membrane chromatography. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Near-Horizon Geodesics for Astrophysical and Idealised Black Holes: Coordinate Velocity and Coordinate Acceleration

Directory of Open Access Journals (Sweden)

Petarpa Boonserm

2018-05-01

Full Text Available Geodesics (by definition have an intrinsic 4-acceleration zero. However, when expressed in terms of coordinates, the coordinate acceleration d 2 x i / d t 2 can very easily be non-zero, and the coordinate velocity d x i / d t can behave unexpectedly. The situation becomes extremely delicate in the near-horizon limit—for both astrophysical and idealised black holes—where an inappropriate choice of coordinates can quite easily lead to significant confusion. We shall carefully explore the relative merits of horizon-penetrating versus horizon-non-penetrating coordinates, arguing that in the near-horizon limit the coordinate acceleration d 2 x i / d t 2 is best interpreted in terms of horizon-penetrating coordinates.

Smart membranes for monitoring membrane based desalination processes

KAUST Repository

Laleg-Kirati, Taous-Meriem; Karam, Ayman M.

2017-01-01

Various examples are related to smart membranes for monitoring membrane based process such as, e.g., membrane distillation processes. In one example, a membrane, includes a porous surface and a plurality of sensors (e.g., temperature, flow and

SASD and the CERN/SPS run-time coordinator

International Nuclear Information System (INIS)

Morpurgo, G.

1990-01-01

Structured Analysis and Structured Design (SASD) provides us with a handy way of specifying the flow of data between the different modules (functional units) of a system. But the formalism loses its immediacy when the control flow has to be taken into account as well. Moreover, due to the lack of appropriate software infrastructure, very often the actual implementation of the system does not reflect the module decoupling and independence so much emphasized at the design stage. In this paper the run-time coordinator, a complete software infrastructure to support a real decoupling of the functional units, is described. Special attention is given to the complementarity of our approach and the SASD methodology. (orig.)

Biomimetic membranes and methods of making biomimetic membranes

Science.gov (United States)

Rempe, Susan; Brinker, Jeffrey C.; Rogers, David Michael; Jiang, Ying-Bing; Yang, Shaorong

2016-11-08

The present disclosure is directed to biomimetic membranes and methods of manufacturing such membranes that include structural features that mimic the structures of cellular membrane channels and produce membrane designs capable of high selectivity and high permeability or adsorptivity. The membrane structure, material and chemistry can be selected to perform liquid separations, gas separation and capture, ion transport and adsorption for a variety of applications.

Gel layer formation on membranes in Membrane Bioreactors

NARCIS (Netherlands)

Van den Brink, P.F.H.

2014-01-01

The widespread application of membrane bioreactors (MBRs) for municipal wastewater treatment is hampered by membrane fouling. Fouling increases energy demand, reduces process performance and creates the need for more frequent (chemical) membrane cleaning or replacement. Membrane fouling in MBRs is

A numerical method for interaction problems between fluid and membranes with arbitrary permeability for fluid

Science.gov (United States)

Miyauchi, Suguru; Takeuchi, Shintaro; Kajishima, Takeo

2017-09-01

We develop a numerical method for fluid-membrane interaction accounting for permeation of the fluid using a non-conforming mesh to the membrane shape. To represent the permeation flux correctly, the proposed finite element discretization incorporates the discontinuities in the velocity gradient and pressure on the membrane surface with specially selected base functions. The discontinuities are represented with independent variables and determined to satisfy the governing equations including the interfacial condition on the permeation. The motions of the fluid, membrane and permeation flux are coupled monolithically and time-advanced fully-implicitly. The validity and effectiveness of the proposed method are demonstrated by several two-dimensional fluid-membrane interaction problems of Stokes flows by comparing with the analytical models and numerical results obtained by other methods. The reproduced sharp discontinuities are found to be essential to suppress the non-physical permeation flux. Further, combined with the numerical treatment for the solute concentration across the membrane, the proposed method is applied to a fluid-structure interaction problem including the osmotic pressure difference.

Investigation of cobalt porphyrin doped polymer membrane films for the optical sensing of imidazole and its derivatives

Directory of Open Access Journals (Sweden)

Yueyang Tan

2015-03-01

Full Text Available A cobalt(II porphyrin was successfully incorporated into polymer membranes for the optical sensing of imidazole and its derivatives. This research has led to a better understanding of the behavior of Co(II porphyrin in solution and in polymeric membranes. In aprotic dichloromethane (DCM, the Co(II tetraphenylporphyrin (CoTPP and Co(II octaethylporphyrin (CoOEP show a sensitive response to imidazole due to the strong ligation of the N-3 on the imidazole ring to the Co(II center, which induces an absorbance change to the Soret band. However, when doped in polymeric films, only the CoTPP exhibits moderate sensitivity towards aqueous imidazole, histamine and histidine. This weakened coordination ability of CoTPP towards imidazole in the polymer films may be due to the coordination of the plasticizer, the impurities from the THF and polymer matrix at the Co(II center. The selectivity of the polymer films towards imidazole over common anions is high. Lifetime of the cobalt(II porphyrin incorporated polymer film was relatively short.

Special relativity at the quantum scale.

Directory of Open Access Journals (Sweden)

Pui K Lam

Full Text Available It has been suggested that the space-time structure as described by the theory of special relativity is a macroscopic manifestation of a more fundamental quantum structure (pre-geometry. Efforts to quantify this idea have come mainly from the area of abstract quantum logic theory. Here we present a preliminary attempt to develop a quantum formulation of special relativity based on a model that retains some geometric attributes. Our model is Feynman's "checker-board" trajectory for a 1-D relativistic free particle. We use this model to guide us in identifying (1 the quantum version of the postulates of special relativity and (2 the appropriate quantum "coordinates". This model possesses a useful feature that it admits an interpretation both in terms of paths in space-time and in terms of quantum states. Based on the quantum version of the postulates, we derive a transformation rule for velocity. This rule reduces to the Einstein's velocity-addition formula in the macroscopic limit and reveals an interesting aspect of time. The 3-D case, time-dilation effect, and invariant interval are also discussed in term of this new formulation. This is a preliminary investigation; some results are derived, while others are interesting observations at this point.

Special relativity at the quantum scale.

Science.gov (United States)

Lam, Pui K

2014-01-01

It has been suggested that the space-time structure as described by the theory of special relativity is a macroscopic manifestation of a more fundamental quantum structure (pre-geometry). Efforts to quantify this idea have come mainly from the area of abstract quantum logic theory. Here we present a preliminary attempt to develop a quantum formulation of special relativity based on a model that retains some geometric attributes. Our model is Feynman's "checker-board" trajectory for a 1-D relativistic free particle. We use this model to guide us in identifying (1) the quantum version of the postulates of special relativity and (2) the appropriate quantum "coordinates". This model possesses a useful feature that it admits an interpretation both in terms of paths in space-time and in terms of quantum states. Based on the quantum version of the postulates, we derive a transformation rule for velocity. This rule reduces to the Einstein's velocity-addition formula in the macroscopic limit and reveals an interesting aspect of time. The 3-D case, time-dilation effect, and invariant interval are also discussed in term of this new formulation. This is a preliminary investigation; some results are derived, while others are interesting observations at this point.

Coordination, non-coordination and semi-coordination of perchlorates in the lanthanide adducts Ln (CLO4)3. 6dmba

International Nuclear Information System (INIS)

Tfouni, E.; Giesbrecht, E.

1983-01-01

The coordination or not of the perchlorate anions in the previously reported Ln(CLO 4 ) 3 .6 dmba is discussed. The analysis of the infrared spectral data and molar conductance data indicate that they may be formulated as [Ln(dmba) 6 (CLO 4 )n] (CLO 4 ) sub(3-n), n=0,1,2. The individual compounds may be a mixture of species with different n values and/or pure compounds with semi-coordinated and non-coordinated perchlorates. (Author) [pt

Tuning of Nafion{sup ®} by HKUST-1 as coordination network to enhance proton conductivity for fuel cell applications

Energy Technology Data Exchange (ETDEWEB)

Kim, Hee Jin, E-mail: zammanbo814@knu.ac.kr [Kyungpook National University, Research Institute of Advanced Energy Technology (Korea, Republic of); Talukdar, Krishan, E-mail: krishantu@yahoo.com; Choi, Sang-June, E-mail: sjchoi@knu.ac.kr [Kyungpook National University, Department of Environmental Engineering (Korea, Republic of)

2016-02-15

Metal-organic frameworks can be intentionally coordinated to achieve improved proton conductivity because they have highly ordered structures and modular nature that serve as a scaffold to anchor acidic groups and develop efficient proton transfer pathways for fuel cell application. Using the concept of a coordination network, the conductivity of Nafion{sup ®} was tuned by the incorporation of HKUST-1. It has Cu{sup II}–paddle wheel type nodes and 1,3,5-benzenetricarboxylate struts, feature accessible sites that provides an improved protonic channel depending on the water content. In spite of the fact that HKUST-1 is neutral, coordinated water molecules are contributed adequately acidic by Cu{sup II} to supply protons to enhance proton conductivity. Water molecules play a vital part in transfer of proton as conducting media and serve as triggers to change proton conductivity through reforming hydrogen bonding networks by water adsorption/desorption process. Increased ion exchange capacity and proton conductivity with lower water uptake of the H{sub 3}PO{sub 4}-doped material, and improved thermal stability (as confirmed by thermogravimetric analysis) were achieved. The structure of HKUST-1 was confirmed via field emission scanning electron microscopy and X-ray diffraction, while the porosity and adsorption desorption capacity were characterized by porosity analysis. Graphical abstract: The H{sub 3}PO{sub 4}-doped HKUST-1/Nafion® composite membrane is demonstrated to be a promising material based on its proton conductivity. HKUST-1 has an average particle diameter of around 15–20 µm. The proton conductivity, IEC values, and the thermal stability of the 2.5 wt% HKUST-1/Nafion® composite membrane suggest that HKUST-1 may be a promising candidate as a proton-conductive material in the polymer electrolyte fuel cell membrane due to its reasonable proton passageway, favorable surface area, lower water uptake with the higher IEC, and proton conductivity of the H

Magnetic Coordinate Systems

Science.gov (United States)

Laundal, K. M.; Richmond, A. D.

2017-03-01

Geospace phenomena such as the aurora, plasma motion, ionospheric currents and associated magnetic field disturbances are highly organized by Earth's main magnetic field. This is due to the fact that the charged particles that comprise space plasma can move almost freely along magnetic field lines, but not across them. For this reason it is sensible to present such phenomena relative to Earth's magnetic field. A large variety of magnetic coordinate systems exist, designed for different purposes and regions, ranging from the magnetopause to the ionosphere. In this paper we review the most common magnetic coordinate systems and describe how they are defined, where they are used, and how to convert between them. The definitions are presented based on the spherical harmonic expansion coefficients of the International Geomagnetic Reference Field (IGRF) and, in some of the coordinate systems, the position of the Sun which we show how to calculate from the time and date. The most detailed coordinate systems take the full IGRF into account and define magnetic latitude and longitude such that they are constant along field lines. These coordinate systems, which are useful at ionospheric altitudes, are non-orthogonal. We show how to handle vectors and vector calculus in such coordinates, and discuss how systematic errors may appear if this is not done correctly.

NMR spectroscopic studies of membrane-bound biological systems

International Nuclear Information System (INIS)

Hohlweg, W.

2013-01-01

In the course of this thesis, biological NMR spectroscopy was employed in studying membrane-bound peptides and proteins, for which structural information is still comparatively hard to obtain. Initial work focused on various model peptides bound to membrane-mimicking micelles, studying the protonation state of arginine in a membrane environment. Strong evidence for a cation-π complex was found in TM7, a peptide which forms the seventh transmembrane helix of subunit a of the vacuolar-type H+-ATPase (V-ATPase). V-ATPase is a physiologically highly relevant proton pump, which is present in intracellular membranes of all eukaryotic organisms, as well as the plasma membrane of several specialized cells. Loss of functional V-ATPase is associated with human diseases such as osteopetrosis, distal renal tubular acidosis or the spreading of cancer. V-ATPase is considered a potential drug target in the treatment of osteoporosis and cancer, or in the development of novel contraceptives. Results from NMR solution structure determination, NMR titration experiments, paramagnetic relaxation enhancement experiments and tryptophan fluorescence spectroscopy confirm the existence of a buried cation-? complex formed between arginine residue R735, which is essential for proton transport, and neighbouring tryptophan and tyrosine residues. In vivo experiments in the yeast Saccharomyces cerevisiae using selective growth tests and fluorescence microscopy showed that formation of the cation-π complex is essential for V-ATPase function. Deletion of both aromatic residues, as well as only the one tryptophan residue leads to growth defects and inability to maintain vacuolar pH homeostasis. These findings shine new light on the still elusive mechanism of proton transport in V-ATPase, and show that arginine R735 may be directly involved in proton transfer across the membrane. (author) [de

Global Proteomic Analysis Reveals an Exclusive Role of Thylakoid Membranes in Bioenergetics of a Model Cyanobacterium

Energy Technology Data Exchange (ETDEWEB)

Liberton, Michelle; Saha, Rajib; Jacobs, Jon M.; Nguyen, Amelia Y.; Gritsenko, Marina A.; Smith, Richard D.; Koppenaal, David W.; Pakrasi, Himadri B.

2016-04-07

Cyanobacteria are photosynthetic microbes with highly differentiated membrane systems. These organisms contain an outer membrane, plasma membrane, and an internal system of thylakoid membranes where the photosynthetic and respiratory machinery are found. This existence of compartmentalization and differentiation of membrane systems poses a number of challenges for cyanobacterial cells in terms of organization and distribution of proteins to the correct membrane system. Proteomics studies have long sought to identify the components of the different membrane systems, and to date about 450 different proteins have been attributed to either the plasma membrane or thylakoid membrane. Given the complexity of these membranes, many more proteins remain to be identified in these membrane systems, and a comprehensive catalog of plasma membrane and thylakoid membrane proteins is needed. Here we describe the identification of 635 proteins in Synechocystis sp. PCC 6803 by quantitative iTRAQ isobaric labeling; of these, 459 proteins were localized to the plasma membrane and 176 were localized to the thylakoid membrane. Surprisingly, we found over 2.5 times the number of unique proteins identified in the plasma membrane compared to the thylakoid membrane. This suggests that the protein composition of the thylakoid membrane is more homogeneous than the plasma membrane, consistent with the role of the plasma membrane in diverse cellular processes including protein trafficking and nutrient import, compared to a more specialized role for the thylakoid membrane in cellular energetics. Overall, the protein composition of the Synechocystis 6803 plasma membrane and thylakoid membrane is quite similar to the E.coli plasma membrane and Arabidopsis thylakoid membrane, respectively. Synechocystis 6803 can therefore be described as a gram-negative bacterium that has an additional internal membrane system that fulfils the energetic requirements of the cell.

Global Proteomic Analysis Reveals an Exclusive Role of Thylakoid Membranes in Bioenergetics of a Model Cyanobacterium

Energy Technology Data Exchange (ETDEWEB)

Liberton, Michelle; Saha, Rajib; Jacobs, Jon M.; Nguyen, Amelia Y.; Gritsenko, Marina A.; Smith, Richard D.; Koppenaal, David W.; Pakrasi, Himadri B.

2016-04-07

Cyanobacteria are photosynthetic microbes with highlydifferentiated membrane systems. These organisms contain an outer membrane, plasma membrane, and an internal system of thylakoid membranes where the photosynthetic and respiratory machinery are found. This existence of compartmentalization and differentiation of membrane systems poses a number of challenges for cyanobacterial cells in terms of organization and distribution of proteins to the correct membrane system. Proteomics studies have long sought to identify the components of the different membrane systems in cyanobacteria, and to date about 450 different proteins have been attributed to either the plasma membrane or thylakoid membrane. Given the complexity of these membranes, many more proteins remain to be identified, and a comprehensive catalogue of plasma membrane and thylakoid membrane proteins is needed. Here we describe the identification of 635 differentially localized proteins in Synechocystis sp. PCC 6803 by quantitative iTRAQ isobaric labeling; of these, 459 proteins were localized to the plasma membrane and 176 were localized to the thylakoid membrane. Surprisingly, we found over 2.5 times the number of unique proteins identified in the plasma membrane compared with the thylakoid membrane. This suggests that the protein composition of the thylakoid membrane is more homogeneous than the plasma membrane, consistent with the role of the plasma membrane in diverse cellular processes including protein trafficking and nutrient import, compared with a more specialized role for the thylakoid membrane in cellular energetics. Thus, our data clearly define the two membrane systems with distinct functions. Overall, the protein compositions of the Synechocystis 6803 plasma membrane and thylakoid membrane are quite similar to that of the plasma membrane of Escherichia coli and thylakoid membrane of Arabidopsis chloroplasts, respectively. Synechocystis 6803 can therefore be described as a Gram

Plasma membrane organization and dynamics is probe and cell line dependent.

Science.gov (United States)

Huang, Shuangru; Lim, Shi Ying; Gupta, Anjali; Bag, Nirmalya; Wohland, Thorsten

2017-09-01

The action and interaction of membrane receptor proteins take place within the plasma membrane. The plasma membrane, however, is not a passive matrix. It rather takes an active role and regulates receptor distribution and function by its composition and the interaction of its lipid components with embedded and surrounding proteins. Furthermore, it is not a homogenous fluid but contains lipid and protein domains of various sizes and characteristic lifetimes which are important in regulating receptor function and signaling. The precise lateral organization of the plasma membrane, the differences between the inner and outer leaflet, and the influence of the cytoskeleton are still debated. Furthermore, there is a lack of comparisons of the organization and dynamics of the plasma membrane of different cell types. Therefore, we used four different specific membrane markers to test the lateral organization, the differences between the inner and outer membrane leaflet, and the influence of the cytoskeleton of up to five different cell lines, including Chinese hamster ovary (CHO-K1), Human cervical carcinoma (HeLa), neuroblastoma (SH-SY5Y), fibroblast (WI-38) and rat basophilic leukemia (RBL-2H3) cells by Imaging Total Internal Reflection (ITIR)-Fluorescence Correlation Spectroscopy (FCS). We measure diffusion in the temperature range of 298-310K to measure the Arrhenius activation energy (E Arr ) of diffusion and apply the FCS diffusion law to obtain information on the spatial organization of the probe molecules on the various cell membranes. Our results show clear differences of the FCS diffusion law and E Arr for the different probes in dependence of their localization. These differences are similar in the outer and inner leaflet of the membrane. However, these values can differ significantly between different cell lines raising the question how molecular plasma membrane events measured in different cell lines can be compared. This article is part of a Special Issue

Nanodisc-solubilized membrane protein library reflects the membrane proteome.

Science.gov (United States)

Marty, Michael T; Wilcox, Kyle C; Klein, William L; Sligar, Stephen G

2013-05-01

The isolation and identification of unknown membrane proteins offers the prospect of discovering new pharmaceutical targets and identifying key biochemical receptors. However, interactions between membrane protein targets and soluble ligands are difficult to study in vitro due to the insolubility of membrane proteins in non-detergent systems. Nanodiscs, nanoscale discoidal lipid bilayers encircled by a membrane scaffold protein belt, have proven to be an effective platform to solubilize membrane proteins and have been used to study a wide variety of purified membrane proteins. This report details the incorporation of an unbiased population of membrane proteins from Escherichia coli membranes into Nanodiscs. This solubilized membrane protein library (SMPL) forms a soluble in vitro model of the membrane proteome. Since Nanodiscs contain isolated proteins or small complexes, the SMPL is an ideal platform for interactomics studies and pull-down assays of membrane proteins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the protein population before and after formation of the Nanodisc library indicates that a large percentage of the proteins are incorporated into the library. Proteomic identification of several prominent bands demonstrates the successful incorporation of outer and inner membrane proteins into the Nanodisc library.

Motor coordination uses external spatial coordinates independent of developmental vision.

Science.gov (United States)

Heed, Tobias; Röder, Brigitte

2014-07-01

The constraints that guide bimanual movement coordination are informative about the processing principles underlying movement planning in humans. For example, symmetry relative to the body midline benefits finger and hand movements independent of hand posture. This symmetry constraint has been interpreted to indicate that movement coordination is guided by a perceptual code. Although it has been assumed implicitly that the perceptual system at the heart of this constraint is vision, this relationship has not been tested. Here, congenitally blind and sighted participants made symmetrical and non-symmetrical (that is, parallel) bimanual tapping and finger oscillation movements. For both groups, symmetrical movements were executed more correctly than parallel movements, independent of anatomical constraints like finger homology and hand posture. For the blind, the reliance on external spatial factors in movement coordination stands in stark contrast to their use of an anatomical reference frame in perceptual processing. Thus, the externally coded symmetry constraint evident in bimanual coordination can develop in the absence of the visual system, suggesting that the visual system is not critical for the establishment of an external-spatial reference frame in movement coordination. Copyright © 2014 Elsevier B.V. All rights reserved.

Interpenetrating polymer network membranes for fuel cells: infrared vibrational spectroscopy; Membranes baseadas dm redes polimericas interpenetrantes para celulas a combustivel: estudo por espectroscopia vibracional no infravermelho

Energy Technology Data Exchange (ETDEWEB)

Loureiro, Felipe A.M.; Rocco, Ana Maria [Grupo de Materiais Condutores e Energia, Escola de Quimica, Universidade Federal do Rio de Janeiro, RJ (Brazil)], e-mail: amrocco@eq.ufrj.br; Pereira, Robson Pacheco [Instituto de Ciencias Exatas, Universidade Federal Fluminense (UFF), Volta Redonda, RJ (Brazil)

2011-07-01

In the present work, proton conductive membranes based on IPN matrices doped with H{sub 3}PO{sub 4} were developed. The characterization by infrared vibrational spectroscopy evidenced the polymerization of DGEBA and the immobilization of PEI chains, originating a structure containing basic sites suitable for proton coordination and conduction. The FTIR characterization evidenced the polymerization of DGEBA in the presence of PEI thus forming Semi-IPN membranes which, after doped with H{sub 3}PO{sub 4}, exhibited conductivity values of 10{sup -4} W{sup -1}cm{sup -1} at room temperature and 10{sup -3} {omega}{sup -1}cm{sup -1} at 80 degree C, as well as a dependency of conductivity with temperature following the Arrhenius model. The activation energy values (14,33 and 12,96 kJ.mol{sup -1}) indicated a proton conduction mechanism predominantly vehicular in the matrices studied under 100% relative humidity. (author)

Flux Enhancement in Membrane Distillation Using Nanofiber Membranes

Directory of Open Access Journals (Sweden)

T. Jiříček

2016-01-01

Full Text Available Membrane distillation (MD is an emerging separation technology, whose largest application potential lies in the desalination of highly concentrated solutions, which are out of the scope of reverse osmosis. Despite many attractive features, this technology is still awaiting large industrial application. The main reason is the lack of commercially available membranes with fluxes comparable to reverse osmosis. MD is a thermal separation process driven by a partial vapour pressure difference. Flux, distillate purity, and thermal efficiency are always in conflict, all three being strictly connected with pore size, membrane hydrophobicity, and thickness. The world has not seen the ideal membrane yet, but nanofibers may offer a solution to these contradictory requirements. Membranes of electrospun PVDF were tested under various conditions on a direct contact (DCMD unit, in order to determine the optimum conditions for maximum flux. In addition, their performance was compared to commonly available PTFE, PE, and PES membranes. It was confirmed that thinner membranes have higher fluxes and a lower distillate purity and also higher energy losses via conduction across the membrane. As both mass and heat transfer are connected, it is best to develop new membranes with a target application in mind, for the specific membrane module and operational conditions.

Investigating the Constrained Action Hypothesis: A Movement Coordination and Coordination Variability Approach.

Science.gov (United States)

Vidal, Anthony; Wu, Will; Nakajima, Mimi; Becker, James

2017-09-19

The purpose of this study was to examine the effects of focus of attention cues on movement coordination and coordination variability in the lower extremity. Twenty participants performed the standing long jump under both internal and external focus of attention conditions. A modified vector coding technique was used to evaluate the influence of attentional focus cues on lower extremity coordination patterns and coordination variability during the jumps. Participants jumped significantly further under an external focus of attention condition compared with an internal focus of attention condition (p = .035, effect size = .29). Focus of attention also influenced coordination between the ankle and knee, F(6, 19) = 2.87, p = .012, effect size = .388, with participants primarily using their knees under the internal focus of attention, and using both their ankles and knees under the external focus of attention. Attentional focus cues did not influence ankle-knee, F(1, 19) = 0.02, p = .98, effect size = .02, or hip-knee, F(1, 19) = 5.00, p = .49, effect size = .16, coordination variability. Results suggest that while attentional focus may not directly influence movement coordination condition, there is still a change in movement strategy resulting in greater jump distances following an external focus of attention.

Fabrication of electrospun nanofibrous membranes for membrane distillation application

KAUST Repository

Francis, Lijo

2013-02-01

Nanofibrous membranes of Matrimid have been successfully fabricated using an electrospinning technique under optimized conditions. Nanofibrous membranes are found to be highly hydrophobic with a high water contact angle of 130°. Field emission scanning electron microscopy and pore size distribution analysis revealed the big pore size structure of electrospun membranes to be greater than 2 μm and the pore size distribution is found to be narrow. Flat sheet Matrimid membranes were fabricated via casting followed by phase inversion. The morphology, pore size distribution, and water contact angle were measured and compared with the electrospun membranes. Both membranes fabricated by electrospinning and phase inversion techniques were tested in a direct contact membrane distillation process. Electrospun membranes showed high water vapor flux of 56 kg/m2-h, which is very high compared to the casted membrane as well as most of the fabricated and commercially available highly hydrophobic membranes. ©2013 Desalination Publications.

Tile-based parallel coordinates and its application in financial visualization

Science.gov (United States)

Alsakran, Jamal; Zhao, Ye; Zhao, Xinlei

2010-01-01

Parallel coordinates technique has been widely used in information visualization applications and it has achieved great success in visualizing multivariate data and perceiving their trends. Nevertheless, visual clutter usually weakens or even diminishes its ability when the data size increases. In this paper, we first propose a tile-based parallel coordinates, where the plotting area is divided into rectangular tiles. Each tile stores an intersection density that counts the total number of polylines intersecting with that tile. Consequently, the intersection density is mapped to optical attributes, such as color and opacity, by interactive transfer functions. The method visualizes the polylines efficiently and informatively in accordance with the density distribution, and thus, reduces visual cluttering and promotes knowledge discovery. The interactivity of our method allows the user to instantaneously manipulate the tiles distribution and the transfer functions. Specifically, the classic parallel coordinates rendering is a special case of our method when each tile represents only one pixel. A case study on a real world data set, U.S. stock mutual fund data of year 2006, is presented to show the capability of our method in visually analyzing financial data. The presented visual analysis is conducted by an expert in the domain of finance. Our method gains the support from professionals in the finance field, they embrace it as a potential investment analysis tool for mutual fund managers, financial planners, and investors.

Alternative energy efficient membrane bioreactor using reciprocating submerged membrane.

Science.gov (United States)

Ho, J; Smith, S; Roh, H K

2014-01-01

A novel membrane bioreactor (MBR) pilot system, using membrane reciprocation instead of air scouring, was operated at constant high flux and daily fluctuating flux to demonstrate its application under peak and diurnal flow conditions. Low and stable transmembrane pressure was achieved at 40 l/m(2)/h (LMH) by use of repetitive membrane reciprocation. The results reveal that the inertial forces acting on the membrane fibers effectively propel foulants from the membrane surface. Reciprocation of the hollow fiber membrane is beneficial for the constant removal of solids that may build up on the membrane surface and inside the membrane bundle. The membrane reciprocation in the reciprocating MBR pilot consumed less energy than coarse air scouring used in conventional MBR systems. Specific energy consumption for the membrane reciprocation was 0.072 kWh/m(3) permeate produced at 40 LMH flux, which is 75% less than for a conventional air scouring system as reported in literature without consideration of energy consumption for biological aeration (0.29 kWh/m(3)). The daily fluctuating flux test confirmed that the membrane reciprocation is effective to handle fluctuating flux up to 50 LMH. The pilot-scale reciprocating MBR system successfully demonstrated that fouling can be controlled via 0.43 Hz membrane reciprocation with 44 mm or higher amplitude.

MEMBRANOUS FLOWS IN GAS-LIQUID COLLECTORS-REGENERATORS OF SOLAR ABSORPTIVE SYSTEMS FEATURES

Directory of Open Access Journals (Sweden)

Doroshenko А.V.

2009-12-01

Full Text Available Article is devoted to the creation of new generation of solar collectors of the gas-liquid type, intended for use in alternative refrigerating and conditioning systems of drying-evaporating type with direct solar regeneration of absorbent. Special attention is given to the study of membranous flows features on inclined surfaces, including questions of such flows stability.

Novel Aluminum Oxide-Impregnated Carbon Nanotube Membrane for the Removal of Cadmium from Aqueous Solution

Directory of Open Access Journals (Sweden)

Ihsanullah

2017-09-01

Full Text Available An aluminum oxide-impregnated carbon nanotube (CNT-Al2O3 membrane was developed via a novel approach and used in the removal of toxic metal cadmium ions, Cd(II. The membrane did not require any binder to hold the carbon nanotubes (CNTs together. Instead, the Al2O3 particles impregnated on the surface of the CNTs were sintered together during heating at 1400 °C. Impregnated CNTs were characterized using XRD, while the CNT-Al2O3 membrane was characterized using scanning electron microscopy (SEM. Water flux, contact angle, and porosity measurements were performed on the membrane prior to the Cd(II ion removal experiment, which was conducted in a specially devised continuous filtration system. The results demonstrated the extreme hydrophilic behavior of the developed membrane, which yielded a high water flux through the membrane. The filtration system removed 84% of the Cd(II ions at pH 7 using CNT membrane with 10% Al2O3 loading. A maximum adsorption capacity of 54 mg/g was predicted by the Langmuir isotherm model for the CNT membrane with 10% Al2O3 loading. This high adsorption capacity indicated that adsorption was the main mechanism involved in the removal of Cd(II ions.

The need for and the importance of biological indicators of radiation effects with special reference to injuries in radiation accidents

International Nuclear Information System (INIS)

Koeteles, G.J.; Bianco, A.

1982-01-01

The need for further research on the existing and new biological indicators of radiation injury has been expressed. The studies on the radiation-induced alterations of membrane structure and function stimulated investigations aiming to develop an indicator based on membrane-phenomena. The co-ordinated research programme on ''Cell Membrane Probes as Biological Indicators of Radiation Injury in Radiation Accidents'' was initiated in mid 1977 and terminated in 1980. Within this programme many basic observations were made in connection with altered features of various animal and human cell membranes. Molecular, biophysical, biochemical and cell biological approaches were performed. The rapid reaction within minutes or hours of membranes against relatively low doses of various types of irradiations were described and the effects proved to be transitory, i.e. membrane regeneration occurred within hours. These dose- and timedependent alterations suggest the possibility of developing a biological indicator which would give signals at the earliest period after radiation injury when no other biological informations are available. The importance of a system of biological indicators is emphasized. (author)

Building a patchwork - The yeast plasma membrane as model to study lateral domain formation.

Science.gov (United States)

Schuberth, Christian; Wedlich-Söldner, Roland

2015-04-01

The plasma membrane (PM) has to fulfill a wide range of biological functions including selective uptake of substances, signal transduction and modulation of cell polarity and cell shape. To allow efficient regulation of these processes many resident proteins and lipids of the PM are laterally segregated into different functional domains. A particularly striking example of lateral segregation has been described for the budding yeast PM, where integral membrane proteins as well as lipids exhibit very slow translational mobility and form a patchwork of many overlapping micron-sized domains. Here we discuss the molecular and physical mechanisms contributing to the formation of a multi-domain membrane and review our current understanding of yeast PM organization. Many of the fundamental principles underlying membrane self-assembly and organization identified in yeast are expected to equally hold true in other organisms, even for the more transient and elusive organization of the PM in mammalian cells. This article is part of a Special Issue entitled: Nanoscale membrane organisation and signalling. Copyright © 2014 Elsevier B.V. All rights reserved.

Membrane order in the plasma membrane and endocytic recycling compartment.

Science.gov (United States)

Iaea, David B; Maxfield, Frederick R

2017-01-01

The cholesterol content of membranes plays an important role in organizing membranes for signal transduction and protein trafficking as well as in modulating the biophysical properties of membranes. While the properties of model or isolated membranes have been extensively studied, there has been little evaluation of internal membranes in living cells. Here, we use a Nile Red based probe, NR12S, and ratiometric live cell imaging, to analyze the membrane order of the plasma membrane and endocytic recycling compartment. We find that after a brief incubation to allow endocytosis, NR12S is distributed between the plasma membrane and the endocytic recycling compartment. The NR12S reports that the endocytic recycling compartment is more highly ordered than the plasma membrane. We also find that the plasma membrane and the endocytic recycling compartment are differentially affected by altering cellular cholesterol levels. The membrane order of the plasma membrane, but not the endocytic recycling compartment, is altered significantly when cellular cholesterol content is increased or decreased by 20%. These results demonstrate that changes in cellular cholesterol differentially alter membrane order within different organelles.

Internationally coordinated glacier monitoring: strategy and datasets

Science.gov (United States)

Hoelzle, Martin; Armstrong, Richard; Fetterer, Florence; Gärtner-Roer, Isabelle; Haeberli, Wilfried; Kääb, Andreas; Kargel, Jeff; Nussbaumer, Samuel; Paul, Frank; Raup, Bruce; Zemp, Michael

2014-05-01

Internationally coordinated monitoring of long-term glacier changes provide key indicator data about global climate change and began in the year 1894 as an internationally coordinated effort to establish standardized observations. Today, world-wide monitoring of glaciers and ice caps is embedded within the Global Climate Observing System (GCOS) in support of the United Nations Framework Convention on Climate Change (UNFCCC) as an important Essential Climate Variable (ECV). The Global Terrestrial Network for Glaciers (GTN-G) was established in 1999 with the task of coordinating measurements and to ensure the continuous development and adaptation of the international strategies to the long-term needs of users in science and policy. The basic monitoring principles must be relevant, feasible, comprehensive and understandable to a wider scientific community as well as to policy makers and the general public. Data access has to be free and unrestricted, the quality of the standardized and calibrated data must be high and a combination of detailed process studies at selected field sites with global coverage by satellite remote sensing is envisaged. Recently a GTN-G Steering Committee was established to guide and advise the operational bodies responsible for the international glacier monitoring, which are the World Glacier Monitoring Service (WGMS), the US National Snow and Ice Data Center (NSIDC), and the Global Land Ice Measurements from Space (GLIMS) initiative. Several online databases containing a wealth of diverse data types having different levels of detail and global coverage provide fast access to continuously updated information on glacier fluctuation and inventory data. For world-wide inventories, data are now available through (a) the World Glacier Inventory containing tabular information of about 130,000 glaciers covering an area of around 240,000 km2, (b) the GLIMS-database containing digital outlines of around 118,000 glaciers with different time stamps and

Evaluation of vertical coordinate and vertical mixing algorithms in the HYbrid-Coordinate Ocean Model (HYCOM)

Science.gov (United States)

Halliwell, George R.

Vertical coordinate and vertical mixing algorithms included in the HYbrid Coordinate Ocean Model (HYCOM) are evaluated in low-resolution climatological simulations of the Atlantic Ocean. The hybrid vertical coordinates are isopycnic in the deep ocean interior, but smoothly transition to level (pressure) coordinates near the ocean surface, to sigma coordinates in shallow water regions, and back again to level coordinates in very shallow water. By comparing simulations to climatology, the best model performance is realized using hybrid coordinates in conjunction with one of the three available differential vertical mixing models: the nonlocal K-Profile Parameterization, the NASA GISS level 2 turbulence closure, and the Mellor-Yamada level 2.5 turbulence closure. Good performance is also achieved using the quasi-slab Price-Weller-Pinkel dynamical instability model. Differences among these simulations are too small relative to other errors and biases to identify the "best" vertical mixing model for low-resolution climate simulations. Model performance deteriorates slightly when the Kraus-Turner slab mixed layer model is used with hybrid coordinates. This deterioration is smallest when solar radiation penetrates beneath the mixed layer and when shear instability mixing is included. A simulation performed using isopycnic coordinates to emulate the Miami Isopycnic Coordinate Ocean Model (MICOM), which uses Kraus-Turner mixing without penetrating shortwave radiation and shear instability mixing, demonstrates that the advantages of switching from isopycnic to hybrid coordinates and including more sophisticated turbulence closures outweigh the negative numerical effects of maintaining hybrid vertical coordinates.

Atomic force microscopy on plasma membranes from Xenopus laevis oocytes containing human aquaporin 4.

Science.gov (United States)

Orsini, Francesco; Santacroce, Massimo; Cremona, Andrea; Gosvami, Nitya N; Lascialfari, Alessandro; Hoogenboom, Bart W

2014-11-01

Atomic force microscopy (AFM) is a unique tool for imaging membrane proteins in near-native environment (embedded in a membrane and in buffer solution) at ~1 nm spatial resolution. It has been most successful on membrane proteins reconstituted in 2D crystals and on some specialized and densely packed native membranes. Here, we report on AFM imaging of purified plasma membranes from Xenopus laevis oocytes, a commonly used system for the heterologous expression of membrane proteins. Isoform M23 of human aquaporin 4 (AQP4-M23) was expressed in the X. laevis oocytes following their injection with AQP4-M23 cRNA. AQP4-M23 expression and incorporation in the plasma membrane were confirmed by the changes in oocyte volume in response to applied osmotic gradients. Oocyte plasma membranes were then purified by ultracentrifugation on a discontinuous sucrose gradient, and the presence of AQP4-M23 proteins in the purified membranes was established by Western blotting analysis. Compared with membranes without over-expressed AQP4-M23, the membranes from AQP4-M23 cRNA injected oocytes showed clusters of structures with lateral size of about 10 nm in the AFM topography images, with a tendency to a fourfold symmetry as may be expected for higher-order arrays of AQP4-M23. In addition, but only infrequently, AQP4-M23 tetramers could be resolved in 2D arrays on top of the plasma membrane, in good quantitative agreement with transmission electron microscopy analysis and the current model of AQP4. Our results show the potential and the difficulties of AFM studies on cloned membrane proteins in native eukaryotic membranes. Copyright © 2014 John Wiley & Sons, Ltd.

77 FR 36544 - Disease, Disability, and Injury Prevention and Control Special Emphasis Panel (SEP): Initial Review

Science.gov (United States)

2012-06-19

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention Disease, Disability, and Injury Prevention and Control Special Emphasis Panel (SEP): Initial Review The meeting announced below concerns Coordinating Center for Research and Training to Promote the Health of People with...

Investigation on influence parameters in measurements of the optomechanical hole plate using an optical coordinate measuring machine

DEFF Research Database (Denmark)

Morace, Renate Erica; Hansen, Hans Nørgaard; De Chiffre, Leonardo

2003-01-01

This paper describes the results of an experimental investigation on influence parameters in optical coordinate measurements of the optomechanical hole plate. Special attention was paid to the background of the object, which strongly influences the measurement result. Furthermore, it is seen that...... influences, the measurements were all performed with no movements of the axes of the CMM....

ORTHODONTIC MANAGEMENT IN CHILDREN WITH SPECIAL NEEDS

Directory of Open Access Journals (Sweden)

Adit ARORA

2013-07-01

Full Text Available Special needs individuals are children or adults pre‐ vented by a physical or mental condition permitting their full participation to the normal range of activities of their age groups. They usually exhibit high orthodontic treat‐ ment needs because of an increased prevalence and seve‐ rity of malocclusions. These conditions often require a coordinated craniofacial orthodontic and surgical treat‐ ment in a team setting, to achieve optimal outcome. Ort‐ hodontic treatments for patients born with facial differences tend to be more complex than ordinary ortho‐ dontics. This multidisciplinary treatment often starts from birth and extends up to the late teen years. The young patient may require treatment by multiple specialists, including a craniofacial surgeon, pediatrician, geneticist, neurosurgeon, ENT, speech and language therapist, pedi‐ atric dentist, oral surgeon and prosthodontist. The objec‐ tive of this paper is to summarize protocols of orthodontic treatment and to present various orthodontic management protocols regarding the children with special needs.

Separation of attractors in 1-modulus quantum corrected special geometry

CERN Document Server

Bellucci, S; Marrani, A; Shcherbakov, A

2008-01-01

We study the solutions to the N=2, d=4 Attractor Equations in a dyonic, extremal, static, spherically symmetric and asymptotically flat black hole background, in the simplest case of perturbative quantum corrected cubic Special Kahler geometry consistent with continuous axion-shift symmetry, namely in the 1-modulus Special Kahler geometry described (in a suitable special symplectic coordinate) by the holomorphic Kahler gauge-invariant prepotential F=t^3+i*lambda, with lambda real. By performing computations in the ``magnetic'' charge configuration, we find evidence for interesting phenomena (absent in the classical limit of vanishing lambda). Namely, for a certain range of the quantum parameter lambda we find a ``splitting'' of attractors, i.e. the existence of multiple solutions to the Attractor Equations for fixed supporting charge configuration. This corresponds to the existence of ``area codes'' in the radial evolution of the scalar t, determined by the various disconnected regions of the moduli space, wh...

Explicitly computing geodetic coordinates from Cartesian coordinates

Science.gov (United States)

Zeng, Huaien

2013-04-01

This paper presents a new form of quartic equation based on Lagrange's extremum law and a Groebner basis under the constraint that the geodetic height is the shortest distance between a given point and the reference ellipsoid. A very explicit and concise formulae of the quartic equation by Ferrari's line is found, which avoids the need of a good starting guess for iterative methods. A new explicit algorithm is then proposed to compute geodetic coordinates from Cartesian coordinates. The convergence region of the algorithm is investigated and the corresponding correct solution is given. Lastly, the algorithm is validated with numerical experiments.

Giant plasma membrane vesicles: models for understanding membrane organization.

Science.gov (United States)

Levental, Kandice R; Levental, Ilya

2015-01-01

The organization of eukaryotic membranes into functional domains continues to fascinate and puzzle cell biologists and biophysicists. The lipid raft hypothesis proposes that collective lipid interactions compartmentalize the membrane into coexisting liquid domains that are central to membrane physiology. This hypothesis has proven controversial because such structures cannot be directly visualized in live cells by light microscopy. The recent observations of liquid-liquid phase separation in biological membranes are an important validation of the raft hypothesis and enable application of the experimental toolbox of membrane physics to a biologically complex phase-separated membrane. This review addresses the role of giant plasma membrane vesicles (GPMVs) in refining the raft hypothesis and expands on the application of GPMVs as an experimental model to answer some of key outstanding problems in membrane biology. Copyright © 2015 Elsevier Inc. All rights reserved.

The casting and mechanism of formation of semi-permeable polymer membranes in a microgravity environment

Science.gov (United States)

Vera, I.

The National Electric Company of Venezuela, C.A.D.A.F.E., is sponsoring the development of this experiment which represents Venezuela's first scientific experiment in space. The apparatus for the automatic casting of polymer thin films will be contained in NASA's payload No. G-559 of the Get Away Special program for a future orbital space flight in the U.S. Space Shuttle. Semi-permeable polymer membranes have important applications in a variety of fields, such as medecine, energy, and pharmaceuticals, and in general fluid separation processes such as reverse osmosis, ultra-filtration, and electro-dialysis. The casting of semi-permeable membranes in space will help to identify the roles of convection in determining the strucutre of these membranes.

Coordination failure caused by sunspots

DEFF Research Database (Denmark)

Beugnot, Julie; Gürgüç, Zeynep; Øvlisen, Frederik Roose

2012-01-01

on the efficient equilibrium, we consider sunspots as a potential reason for coordination failure. We conduct an experiment with a three player 2x2x2 game in which coordination on the efficient equilibrium is easy and should normally occur. In the control session, we find almost perfect coordination on the payoff......-dominant equilibrium, but in the sunspot treatment, dis-coordination is frequent. Sunspots lead to significant inefficiency, and we conclude that sunspots can indeed cause coordination failure....

Structure and physical properties of bio membranes and model membranes

International Nuclear Information System (INIS)

Tibor Hianik

2006-01-01

Bio membranes belong to the most important structures of the cell and the cell organelles. They play not only structural role of the barrier separating the external and internal part of the membrane but contain also various functional molecules, like receptors, ionic channels, carriers and enzymes. The cell membrane also preserves non-equilibrium state in a cell which is crucial for maintaining its excitability and other signaling functions. The growing interest to the bio membranes is also due to their unique physical properties. From physical point of view the bio membranes, that are composed of lipid bilayer into which are incorporated integral proteins and on their surface are anchored peripheral proteins and polysaccharides, represent liquid s crystal of smectic type. The bio membranes are characterized by anisotropy of structural and physical properties. The complex structure of bio membranes makes the study of their physical properties rather difficult. Therefore several model systems that mimic the structure of bio membranes were developed. Among them the lipid monolayers at an air-water interphase, bilayer lipid membranes, supported bilayer lipid membranes and liposomes are most known. This work is focused on the introduction into the physical word of the bio membranes and their models. After introduction to the membrane structure and the history of its establishment, the physical properties of the bio membranes and their models are stepwise presented. The most focus is on the properties of lipid monolayers, bilayer lipid membranes, supported bilayer lipid membranes and liposomes that were most detailed studied. This lecture has tutorial character that may be useful for undergraduate and graduate students in the area of biophysics, biochemistry, molecular biology and bioengineering, however it contains also original work of the author and his co-worker and PhD students, that may be useful also for specialists working in the field of bio membranes and model

Exocyst and autophagy-related membrane trafficking in plants.

Science.gov (United States)

Pecenková, Tamara; Markovic, Vedrana; Sabol, Peter; Kulich, Ivan; Žárský, Viktor

2017-12-18

Endomembrane traffic in eukaryotic cells functions partially as a means of communication; delivery of membrane in one direction has to be balanced with a reduction at the other end. This effect is typically the case during the defence against pathogens. To combat pathogens, cellular growth and differentiation are suppressed, while endomembrane traffic is poised towards limiting the pathogen attack. The octameric exocyst vesicle-tethering complex was originally discovered as a factor facilitating vesicle-targeting and vesicle-plasma membrane (PM) fusion during exocytosis prior to and possibly during SNARE complex formation. Interestingly, it was recently implicated both in animals and plants in autophagy membrane traffic. In animal cells, the exocyst is integrated into the mTOR-regulated energy metabolism stress/starvation pathway, participating in the formation and especially initiation of an autophagosome. In plants, the first functional link was to autophagy-related anthocyanin import to the vacuole and to starvation. In this concise review, we summarize the current knowledge of exocyst functions in autophagy and defence in plants that might involve unconventional secretion and compare it with animal conditions. Formation of different exocyst complexes during undisturbed cell growth, as opposed to periods of cellular stress reactions involving autophagy, might contribute to the coordination of endomembrane trafficking pathways. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Effect of CO{sub 2}-laser irradiation on properties and performance of thin-film composite polyamide reverse osmosis membrane

Energy Technology Data Exchange (ETDEWEB)

Jahangiri, Foad; Mousavi, Seyyed Abbas; Farhadi, Fathollah; Sabzi, Behnam; Chenari, Zeinab [Sharif University of Technology, Tehran (Iran, Islamic Republic of); Vatanpour, Vahid [Kharazmi (Tarbiat Moallem) University, Tehran (Iran, Islamic Republic of)

2016-03-15

CO{sub 2}-laser irradiation was used to modify the surface properties of thin-film composite (TFC) polyamide reverse osmosis (RO) membranes. These membranes were first synthesized via interfacial polymerization of m-phenylenediamine (MPD) monomers and trimesoyl chloride (TMC) over porous polysulfone ultrafiltration support, followed by a CO{sub 2}-irradiation. AFM, ATR-FTIR, SEM and contact angle measurements were used to characterize the surface properties of these membranes. The ATR-FTIR results indicated that CO{sub 2}-laser irradiation did not induce any functional groups on the membrane surface. However, it was found that the laser irradiation enhanced the NaCl salt rejection and slightly reduced the permeate flux. Moreover, the maintenance of the flux in modified membranes was much higher than untreated ones. Specially, after 180 min of filtration, the reduction in initial flux for the unmodified membranes was 22%. However, the reduction in initial flux for the modified membranes was less than 5%. Bovine serum albumin (BSA) filtration revealed an improvement in the antifouling properties of the modified membranes. The changes in the membrane surface morphology showed that the roughness of membrane surface is reduced significantly.

Using membrane transporters to improve crops for sustainable food production

Science.gov (United States)

Schroeder, Julian I.; Delhaize, Emmanuel; Frommer, Wolf B.; Guerinot, Mary Lou; Harrison, Maria J.; Herrera-Estrella, Luis; Horie, Tomoaki; Kochian, Leon V.; Munns, Rana; Nishizawa, Naoko K.; Tsay, Yi-Fang; Sanders, Dale

2013-01-01

With the global population predicted to grow by at least 25 per cent by 2050, the need for sustainable production of nutritious foods is critical for human and environmental health. Recent advances show that specialized plant membrane transporters can be used to enhance yields of staple crops, increase nutrient content and increase resistance to key stresses, including salinity, pathogens and aluminium toxicity, which in turn could expand available arable land. PMID:23636397

Immigrant Families, Children With Special Health Care Needs, and the Medical Home.

Science.gov (United States)

Kan, Kristin; Choi, Hwajung; Davis, Matthew

2016-01-01

Immigrant children in the United States historically experience lower-quality health care. Such disparities areconcerning for immigrant children with special health care needs (CSHCNs). Our study assesses the medical home presence for CSHCN by immigrant family type and evaluates which medical home components are associated with disparities. We used the 2011 National Survey of Children's Health, comparing the prevalence and odds of a parent-reported medical home and 5 specific medical home components by immigrant family types using bivariate and multivariate logistic regression. Foreign-born CSHCNs were less likely than CSHCNs with US-born parents to have a medical home (adjusted odds ratio = 0.40, 95% confidence interval 0.19-0.85). The adjusted prevalence of having a medical home was 28% among foreign-born CSHCNs (P special needs also had a lower odds of a medical home, compared with children with US-born parents (adjusted odds ratio = 0.62, 0.46-0.83). The medical home component most frequently absent for immigrant children without special needs and CSHCNs with a foreign-born parent was family-centered care. In contrast, foreign-born CSHCNs most often lacked care coordination (adjusted prevalence = 37% versus 56% for CSHCNs with US-born parents; P < .05). Disparities in medical home presence for CSHCNs appear to be exacerbated by immigrant family type. Efforts focused on improving family-centered care and care coordination may provide the greatest benefit for immigrant CSHCNs. Copyright © 2016 by the American Academy of Pediatrics.

Polyurethane Nanofiber Membranes for Waste Water Treatment by Membrane Distillation

Directory of Open Access Journals (Sweden)

T. Jiříček

2017-01-01

Full Text Available Self-sustained electrospun polyurethane nanofiber membranes were manufactured and tested on a direct-contact membrane distillation unit in an effort to find the optimum membrane thickness to maximize flux rate and minimize heat losses across the membrane. Also salt retention and flux at high salinities up to 100 g kg−1 were evaluated. Even though the complex structure of nanofiber layers has extreme specific surface and porosity, membrane performance was surprisingly predictable; the highest flux was achieved with the thinnest membranes and the best energy efficiency was achieved with the thickest membranes. All membranes had salt retention above 99%. Nanotechnology offers the potential to find modern solutions for desalination of waste waters, by introducing new materials with revolutionary properties, but new membranes must be developed according to the target application.

Design of a Composite Membrane with Patches

International Nuclear Information System (INIS)

Cuccu, Fabrizio; Emamizadeh, Behrouz; Porru, Giovanni

2010-01-01

This paper is concerned with minimization and maximization problems of eigenvalues. The principal eigenvalue of a differential operator is minimized or maximized over a set which is formed by intersecting a rearrangement class with an affine subspace of finite co-dimension. A solution represents an optimal design of a 2-dimensional composite membrane Ω, fixed at the boundary, built out of two different materials, where certain prescribed regions (patches) in Ω are occupied by both materials. We prove existence results, and present some features of optimal solutions. The special case of one patch is treated in detail.

Technical note concerning the use of cellulose ester filtering membranes in the determination of plutonium in urine

International Nuclear Information System (INIS)

Harduin, J.C.; Montels, P.

1968-01-01

During the last stage of the determination of plutonium in biological media, cellulose ester filtering membranes are used for collecting, with the help of a special device, the very fine precipitate resulting from the co-precipitation of plutonium and lanthanum fluorides. The membranes are then dried, and stuck on to flat watch-glasses for a α counting. A method is then given for purifying the lanthanum so as to keep the background noise during counting as low as possible. (author) [fr

Fouling in Membrane Distillation, Osmotic Distillation and Osmotic Membrane Distillation

Directory of Open Access Journals (Sweden)

Mourad Laqbaqbi

2017-03-01

Full Text Available Various membrane separation processes are being used for seawater desalination and treatment of wastewaters in order to deal with the worldwide water shortage problem. Different types of membranes of distinct morphologies, structures and physico-chemical characteristics are employed. Among the considered membrane technologies, membrane distillation (MD, osmotic distillation (OD and osmotic membrane distillation (OMD use porous and hydrophobic membranes for production of distilled water and/or concentration of wastewaters for recovery and recycling of valuable compounds. However, the efficiency of these technologies is hampered by fouling phenomena. This refers to the accumulation of organic/inorganic deposits including biological matter on the membrane surface and/or in the membrane pores. Fouling in MD, OD and OMD differs from that observed in electric and pressure-driven membrane processes such electrodialysis (ED, membrane capacitive deionization (MCD, reverse osmosis (RO, nanofiltration (NF, ultrafiltration (UF, microfiltration (MF, etc. Other than pore blockage, fouling in MD, OD and OMD increases the risk of membrane pores wetting and reduces therefore the quantity and quality of the produced water or the concentration efficiency of the process. This review deals with the observed fouling phenomena in MD, OD and OMD. It highlights different detected fouling types (organic fouling, inorganic fouling and biofouling, fouling characterization techniques as well as various methods of fouling reduction including pretreatment, membrane modification, membrane cleaning and antiscalants application.

Unique battery with a multi-functional, physicochemically active membrane separator/electrolyte-electrode monolith and a method making the same

Science.gov (United States)

Gerald II, Rex E.; Ruscic, Katarina J.; Sears, Devin N.; Smith, Luis J.; Klingler, Robert J.; Rathke, Jerome W.

2012-07-24

The invention relates to a unique battery having a physicochemically active membrane separator/electrolyte-electrode monolith and method of making the same. The Applicant's invented battery employs a physicochemically active membrane separator/electrolyte-electrode that acts as a separator, electrolyte, and electrode, within the same monolithic structure. The chemical composition, physical arrangement of molecules, and physical geometry of the pores play a role in the sequestration and conduction of ions. In one preferred embodiment, ions are transported via the ion-hoping mechanism where the oxygens of the Al2O3 wall are available for positive ion coordination (i.e. Li+). This active membrane-electrode composite can be adjusted to a desired level of ion conductivity by manipulating the chemical composition and structure of the pore wall to either increase or decrease ion conduction.

Alpha detection in pipes using an inverting membrane scintillator

International Nuclear Information System (INIS)

Kendrick, D.T.; Cremer, C.D.; Lowry, W.; Cramer, E.

1995-01-01

Characterization of surface alpha emitting contamination inside enclosed spaces such as piping systems presents an interesting radiological measurement challenge. Detection of these alpha particles from the exterior of the pipe is impossible since the alpha particles are completely absorbed by the pipe wall. Traditional survey techniques, using hand-held instruments, simply can not be used effectively inside pipes. Science and Engineering Associates, Inc. is currently developing an enhancement to its Pipe Explorer trademark system that will address this challenge. The Pipe Explorer trademark uses a unique sensor deployment method where an inverted tubular membrane is propagated through complex pipe runs via air pressure. The inversion process causes the membrane to fold out against the pipe wall, such that no part of the membrane drags along the pipe wall. This deployment methodology has been successfully demonstrated at several DOE sites to transport specially designed beta and gamma scintillation detectors into pipes ranging in length up to 250 ft. The measurement methodology under development overcomes the limitations associated with conventional hand-held survey instruments by remotely emplacing an alpha scintillator in direct contact with the interior pipe surface over the entire length to be characterized. This is accomplished by incorporating a suitable scintillator into the otherwise clear membrane material. Alpha particles emitted from the interior pipe surface will intersect the membrane, resulting in the emission of light pulses from the scintillator. A photodetector, towed by the inverting membrane, is used to count these light pulses as a function of distance into the pipe, thereby producing a log of the surface alpha contamination levels. It is anticipated that the resulting system will be able to perform measurements in pipes as small as two inches in diameter, and several hundred feet in length

Efficient synthesis of tension modulation in strings and membranes based on energy estimation.

Science.gov (United States)

Avanzini, Federico; Marogna, Riccardo; Bank, Balázs

2012-01-01

String and membrane vibrations cannot be considered as linear above a certain amplitude due to the variation in string or membrane tension. A relevant special case is when the tension is spatially constant and varies in time only in dependence of the overall string length or membrane surface. The most apparent perceptual effect of this tension modulation phenomenon is the exponential decay of pitch in time. Pitch glides due to tension modulation are an important timbral characteristic of several musical instruments, including the electric guitar and tom-tom drum, and many ethnic instruments. This paper presents a unified formulation to the tension modulation problem for one-dimensional (1-D) (string) and two-dimensional (2-D) (membrane) cases. In addition, it shows that the short-time average of the tension variation, which is responsible for pitch glides, is approximately proportional to the system energy. This proportionality allows the efficient physics-based sound synthesis of pitch glides. The proposed models require only slightly more computational resources than linear models as opposed to earlier tension-modulated models of higher complexity. © 2012 Acoustical Society of America.

Flow and fouling in membrane filters: Effects of membrane morphology

Science.gov (United States)

Sanaei, Pejman; Cummings, Linda J.

2015-11-01

Membrane filters are widely-used in microfiltration applications. Many types of filter membranes are produced commercially, for different filtration applications, but broadly speaking the requirements are to achieve fine control of separation, with low power consumption. The answer to this problem might seem obvious: select the membrane with the largest pore size and void fraction consistent with the separation requirements. However, membrane fouling (an inevitable consequence of successful filtration) is a complicated process, which depends on many parameters other than membrane pore size and void fraction; and which itself greatly affects the filtration process and membrane functionality. In this work we formulate mathematical models that can (i) account for the membrane internal morphology (internal structure, pore size & shape, etc.); (ii) fouling of membranes with specific morphology; and (iii) make some predictions as to what type of membrane morphology might offer optimum filtration performance.

Spatial organization and coordination of slow waves in the mouse anorectum

Science.gov (United States)

Hall, K A; Ward, S M; Cobine, C A; Keef, K D

2014-01-01

The internal anal sphincter (IAS) develops tone and is important for maintaining a high anal pressure while tone in the rectum is less. The mechanisms responsible for tone generation in the IAS are still uncertain. The present study addressed this question by comparing the electrical properties and morphology of the mouse IAS and distal rectum. The amplitude of tone and the frequency of phasic contractions was greater in the IAS than in rectum while membrane potential (Em) was less negative in the IAS than in rectum. Slow waves (SWs) were of greatest amplitude and frequency at the distal end of the IAS, declining in the oral direction. Dual microelectrode recordings revealed that SWs were coordinated over a much greater distance in the circumferential direction than in the oral direction. The circular muscle layer of the IAS was divided into five to eight ‘minibundles’ separated by connective tissue septa whereas few septa were present in the rectum. The limited coordination of SWs in the oral direction suggests that the activity in adjacent minibundles is not coordinated. Intramuscular interstitial cells of Cajal and platelet-derived growth factor receptor alpha-positive cells were present in each minibundle suggesting a role for one or both of these cells in SW generation. In summary, three important properties distinguish the IAS from the distal rectum: (1) a more depolarized Em; (2) larger and higher frequency SWs; and (3) the multiunit configuration of the muscle. All of these characteristics may contribute to greater tone generation in the IAS than in the distal rectum. PMID:24951622

Report of the second research co-ordination meeting on the co-ordinated research programme: rapid instrumental and separation methods for monitoring radionuclides in food and environmental samples

International Nuclear Information System (INIS)

1992-10-01

The purpose of this Second Research Co-ordinated Meeting (12-16 August 1991) on Rapid Instrumental and Separation Methods for Monitoring Radionuclides in Food and Environmental Samples is to discuss the progress of the programmes since the First Research Co-ordination Meeting, discuss how to validate the methodologies developed (e.g. reference samples, intercomparisons), and outline a schedule for CRP completion by the end of 1992. Radioactive contamination of the environment after a nuclear accident, such as had occurred at Chernobyl, is of serious concern to government officials and members of the general public. In 1990/1991 the Agency was asked to organize the International Chernobyl Project to assess the situation in the USSR. A network of laboratories was organized to carry out the environmental assessment needed for this project. The following recommendations are based on the experience gained by many of the laboratories involved in this project. 1. Maintain a network of analytical laboratories with special skills and experience to provide assessments of radionuclide contamination in the environment in case of a radiological emergency. 2. Methodologies for assessment of contamination in the environment should take into consideration potential trajectories, radioecology, and food chain parameters. 3. Focus on areas of representative sample collection, is situ instrumental and chemical analysis, as well as advanced streamlined laboratory analyses which will facilitate the timeline of an assessment. 4. Conduct intercomparison and testing of technologies, employing standard reference materials and procedures, and field measurements at significantly contaminated area. 5. Conduct training of Member State laboratory personnel through fellowships, special courses, and workshops. 5 refs

Threedimensional system of coordinates used at CERN

International Nuclear Information System (INIS)

Gervaise, J.; Mayoud, M.; Menant, E.

1976-01-01

This report is a complete account of the transformations and corrections necessary for geodetic quantities, whether directly measured or derived, before they can be entered into calculations involving the basic reference system used at CERN. A special type of projection (orthographic projection) has been developed, with the aim that it be the best possible for the geodetic system employed for the Super Proton Synchrotron (SPS) whilst retaining the basic possibilities provided for the Proton Synchrotron (PS) and the Intersecting Storage Rings (ISR). The coordinate system in which the geometry of particle beams is defined is necessarily Cartesian. This feature, although mathematically simple, has a number of consequences for the treatment of measurements which are physically connected with the shape of the Earth. Details of the orthographic projection, the planimetry, and the altimetry are given. (Author) [fr

Targeting and Assembly of Components of the TOC Protein Import Complex at the Chloroplast Outer Envelope Membrane

Directory of Open Access Journals (Sweden)

Lynn G.L. Richardson

2014-06-01

Full Text Available The translocon at the outer envelope membrane of chloroplasts (TOC initiates the import of thousands of nuclear encoded preproteins required for chloroplast biogenesis and function. The multimeric TOC complex contains two GTP-regulated receptors, Toc34 and Toc159, which recognize the transit peptides of preproteins and initiate protein import through a β–barrel membrane channel, Toc75. Different isoforms of Toc34 and Toc159 assemble with Toc75 to form structurally and functionally diverse translocons, and the composition and levels of TOC translocons is required for the import of specific subsets of coordinately expressed proteins during plant growth and development. Consequently, the proper assembly of the TOC complexes is key to ensuring organelle homeostasis. This review will focus on our current knowledge of the targeting and assembly of TOC components to form functional translocons at the outer membrane. Our analyses reveal that the targeting of TOC components involves elements common to the targeting of other outer membrane proteins, but also include unique features that appear to have evolved to specifically facilitate assembly of the import apparatus.

Targeting and assembly of components of the TOC protein import complex at the chloroplast outer envelope membrane.

Science.gov (United States)

Richardson, Lynn G L; Paila, Yamuna D; Siman, Steven R; Chen, Yi; Smith, Matthew D; Schnell, Danny J

2014-01-01

The translocon at the outer envelope membrane of chloroplasts (TOC) initiates the import of thousands of nuclear encoded preproteins required for chloroplast biogenesis and function. The multimeric TOC complex contains two GTP-regulated receptors, Toc34 and Toc159, which recognize the transit peptides of preproteins and initiate protein import through a β-barrel membrane channel, Toc75. Different isoforms of Toc34 and Toc159 assemble with Toc75 to form structurally and functionally diverse translocons, and the composition and levels of TOC translocons is required for the import of specific subsets of coordinately expressed proteins during plant growth and development. Consequently, the proper assembly of the TOC complexes is key to ensuring organelle homeostasis. This review will focus on our current knowledge of the targeting and assembly of TOC components to form functional translocons at the outer membrane. Our analyses reveal that the targeting of TOC components involves elements common to the targeting of other outer membrane proteins, but also include unique features that appear to have evolved to specifically facilitate assembly of the import apparatus.

Free energies of stable and metastable pores in lipid membranes under tension.

Science.gov (United States)

den Otter, Wouter K

2009-11-28

The free energy profile of pore formation in a lipid membrane, covering the entire range from a density fluctuation in an intact bilayer to a large tension-stabilized pore, has been calculated by molecular dynamics simulations with a coarse-grained lipid model. Several fixed elongations are used to obtain the Helmholtz free energy as a function of pore size for thermodynamically stable, metastable, and unstable pores, and the system-size dependence of these elongations is discussed. A link to the Gibbs free energy at constant tension, commonly known as the Litster model, is established by a Legendre transformation. The change of genus upon pore formation is exploited to estimate the saddle-splay modulus or Gaussian curvature modulus of the membrane leaflets. Details are provided of the simulation approach, which combines the potential of mean constraint force method with a reaction coordinate based on the local lipid density.

Fundamentals of membrane bioreactors materials, systems and membrane fouling

CERN Document Server

Ladewig, Bradley

2017-01-01

This book provides a critical, carefully researched, up-to-date summary of membranes for membrane bioreactors. It presents a comprehensive and self-contained outline of the fundamentals of membrane bioreactors, especially their relevance as an advanced water treatment technology. This outline helps to bring the technology to the readers’ attention, and positions the critical topic of membrane fouling as one of the key impediments to its more widescale adoption. The target readership includes researchers and industrial practitioners with an interest in membrane bioreactors.

Secretion of bacterial lipoproteins: through the cytoplasmic membrane, the periplasm and beyond.

Science.gov (United States)

Zückert, Wolfram R

2014-08-01

, likely through interaction with a periplasmic holding chaperone, which delivers the proteins to an outer membrane lipoprotein flippase. This article is part of a Special Issue entitled: Protein trafficking and secretion in bacteria. Guest Editors: Anastassios Economou and Ross Dalbey. Copyright © 2014 Elsevier B.V. All rights reserved.

[Community coordination of dental care needs in a home medical care support ward and at home].

Science.gov (United States)

Sumi, Yasunori; Ozawa, Nobuyoshi; Miura, Hiroko; Miura, Hisayuki; Toba, Kenji

2011-01-01

The purpose of this study was to ascertain the current statuses and problems of dental home care patients by surveying the oral care status and needs of patients in the home medical care support ward at the National Center for Geriatrics and Gerontology. Patients that required continuous oral management even after discharge from the hospital were referred to local dental clinics to receive home dental care. We investigated the suitability and problems associated with such care, and identified the dental care needs of home patients and the status of local care coordination, including those in hospitals. The subjects were 82 patients. We ascertained their general condition and oral status, and also investigated the problems associated with patients judged to need specialized oral care by a dentist during oral treatment. Patients who required continuous specialized oral care after discharge from hospital were referred to dental clinics that could provide regular care, and the problems at the time of referral were identified. Dry mouth was reported by many patients. A large number of patients also needed specialized dental treatment such as the removal of dental calculus or tooth extraction. Problems were seen in oral function, with 38 of the patients (46%) unable to gargle and 23 (28%) unable to hold their mouths open. About half of the patients also had dementia, and communication with these patients was difficult. Of the 43 patients who were judged to need continuing oral care after discharge from hospital, their referral to a dental clinic for regular care was successful for 22 (51%) patients and unsuccessful for 21 (49%) patients. The reasons for unsuccessful referrals included the fact that the family, patient, nurse, or caregiver did not understand the need for specialized oral care. The present results suggest the need for specialized oral treatment in home medical care. These findings also suggest that coordinating seamless dental care among primary physicians

Conformational transitions and interactions underlying the function of membrane embedded receptor protein kinases.

Science.gov (United States)

Bocharov, Eduard V; Sharonov, Georgy V; Bocharova, Olga V; Pavlov, Konstantin V

2017-09-01

Among membrane receptors, the single-span receptor protein kinases occupy a broad but specific functional niche determined by distinctive features of the underlying transmembrane signaling mechanisms that are briefly overviewed on the basis of some of the most representative examples, followed by a more detailed discussion of several hierarchical levels of organization and interactions involved. All these levels, including single-molecule interactions (e.g., dimerization, liganding, chemical modifications), local processes (e.g. lipid membrane perturbations, cytoskeletal interactions), and larger scale phenomena (e.g., effects of membrane surface shape or electrochemical potential gradients) appear to be closely integrated to achieve the observed diversity of the receptor functioning. Different species of receptor protein kinases meet their specific functional demands through different structural features defining their responses to stimulation, but certain common patterns exist. Signaling by receptor protein kinases is typically associated with the receptor dimerization and clustering, ligand-induced rearrangements of receptor domains through allosteric conformational transitions with involvement of lipids, release of the sequestered lipids, restriction of receptor diffusion, cytoskeleton and membrane shape remodeling. Understanding of complexity and continuity of the signaling processes can help identifying currently neglected opportunities for influencing the receptor signaling with potential therapeutic implications. This article is part of a Special Issue entitled: Interactions between membrane receptors in cellular membranes edited by Kalina Hristova. Copyright © 2017 Elsevier B.V. All rights reserved.

Adaptive silicone-membrane lenses: planar vs. shaped membrane

CSIR Research Space (South Africa)

Schneider, F

2009-08-01

Full Text Available Engineering, Georges-Koehler-Allee 102, Freiburg 79110, Germany florian.schneider@imtek.uni-freiburg.de ABSTRACT We compare the performance and optical quality of two types of adaptive fluidic silicone-membrane lenses. The membranes feature either a...-membrane lenses: planar vs. shaped membrane Florian Schneider1,2, Philipp Waibel2 and Ulrike Wallrabe2 1 CSIR, Materials Science and Manufacturing, PO Box 395, Pretoria 0001, South Africa 2 University of Freiburg – IMTEK, Department of Microsystems...

Degradation of Polypropylene Membranes Applied in Membrane Distillation Crystallizer

Directory of Open Access Journals (Sweden)

Marek Gryta

2016-03-01

Full Text Available The studies on the resistance to degradation of capillary polypropylene membranes assembled in a membrane crystallizer were performed. The supersaturation state of salt was achieved by evaporation of water from the NaCl saturated solutions using membrane distillation process. A high feed temperature (363 K was used in order to enhance the degradation effects and to shorten the test times. Salt crystallization was carried out by the application of batch or fluidized bed crystallizer. A significant membrane scaling was observed regardless of the method of realized crystallization. The SEM-EDS, DSC, and FTIR methods were used for investigations of polypropylene degradation. The salt crystallization onto the membrane surface accelerated polypropylene degradation. Due to a polymer degradation, the presence of carbonyl groups on the membranes’ surface was identified. Besides the changes in the chemical structure a significant mechanical damage of the membranes, mainly caused by the internal scaling, was also found. As a result, the membranes were severely damaged after 150 h of process operation. A high level of salt rejection was maintained despite damage to the external membrane surface.

RssAB signaling coordinates early development of surface multicellularity in Serratia marcescens.

Directory of Open Access Journals (Sweden)

Yu-Huan Tsai

Full Text Available Bacteria can coordinate several multicellular behaviors in response to environmental changes. Among these, swarming and biofilm formation have attracted significant attention for their correlation with bacterial pathogenicity. However, little is known about when and where the signaling occurs to trigger either swarming or biofilm formation. We have previously identified an RssAB two-component system involved in the regulation of swarming motility and biofilm formation in Serratia marcescens. Here we monitored the RssAB signaling status within single cells by tracing the location of the translational fusion protein EGFP-RssB following development of swarming or biofilm formation. RssAB signaling is specifically activated before surface migration in swarming development and during the early stage of biofilm formation. The activation results in the release of RssB from its cognate inner membrane sensor kinase, RssA, to the cytoplasm where the downstream gene promoters are located. Such dynamic localization of RssB requires phosphorylation of this regulator. By revealing the temporal activation of RssAB signaling following development of surface multicellular behavior, our findings contribute to an improved understanding of how bacteria coordinate their lifestyle on a surface.

Membrane fusion

DEFF Research Database (Denmark)

Bendix, Pól Martin

2015-01-01

At Stanford University, Boxer lab, I worked on membrane fusion of small unilamellar lipid vesicles to flat membranes tethered to glass surfaces. This geometry closely resembles biological systems in which liposomes fuse to plasma membranes. The fusion mechanism was studied using DNA zippering...... between complementary strands linked to the two apposing membranes closely mimicking the zippering mechanism of SNARE fusion complexes....

Introducing Membrane Charge and Membrane Potential to T Cell Signaling

Directory of Open Access Journals (Sweden)

Yuanqing Ma

2017-11-01

Full Text Available While membrane models now include the heterogeneous distribution of lipids, the impact of membrane charges on regulating the association of proteins with the plasma membrane is often overlooked. Charged lipids are asymmetrically distributed between the two leaflets of the plasma membrane, resulting in the inner leaflet being negatively charged and a surface potential that attracts and binds positively charged ions, proteins, and peptide motifs. These interactions not only create a transmembrane potential but they can also facilitate the formation of charged membrane domains. Here, we reference fields outside of immunology in which consequences of membrane charge are better characterized to highlight important mechanisms. We then focus on T cell receptor (TCR signaling, reviewing the evidence that membrane charges and membrane-associated calcium regulate phosphorylation of the TCR–CD3 complex and discuss how the immunological synapse exhibits distinct patterns of membrane charge distribution. We propose that charged lipids, ions in solution, and transient protein interactions form a dynamic equilibrium during T cell activation.

Polyazole hollow fiber membranes for direct contact membrane distillation

KAUST Repository

Maab, Husnul; Alsaadi, Ahmad Salem; Francis, Lijo; Livazovic, Sara; Ghaffour, NorEddine; Amy, Gary L.; Nunes, Suzana Pereira

2013-01-01

Porous hollow fiber membranes were fabricated from fluorinated polyoxadiazole and polytriazole by a dry-wet spinning method for application in desalination of Red Sea water by direct contact membrane distillation (DCMD). The data were compared with commercially available hollow fiber MD membranes prepared from poly(vinylidene fluoride). The membranes were characterized by electron microscopy, liquid entry pressure (LEP), and pore diameter measurements. Finally, the hollow fiber membranes were tested for DCMD. Salt selectivity as high as 99.95% and water fluxes as high as 35 and 41 L m -2 h-1 were demonstrated, respectively, for polyoxadiazole and polytriazole hollow fiber membranes, operating at 80 C feed temperature and 20 C permeate. © 2013 American Chemical Society.

Polyazole hollow fiber membranes for direct contact membrane distillation

KAUST Repository

Maab, Husnul

2013-08-07

Porous hollow fiber membranes were fabricated from fluorinated polyoxadiazole and polytriazole by a dry-wet spinning method for application in desalination of Red Sea water by direct contact membrane distillation (DCMD). The data were compared with commercially available hollow fiber MD membranes prepared from poly(vinylidene fluoride). The membranes were characterized by electron microscopy, liquid entry pressure (LEP), and pore diameter measurements. Finally, the hollow fiber membranes were tested for DCMD. Salt selectivity as high as 99.95% and water fluxes as high as 35 and 41 L m -2 h-1 were demonstrated, respectively, for polyoxadiazole and polytriazole hollow fiber membranes, operating at 80 C feed temperature and 20 C permeate. © 2013 American Chemical Society.

The Survey of the Knowledge and Skills Required for Transition Teachers in High School Divisions of Special Needs Education with Intellectual Disabilities : Based on the opinions of transition teachers in high school divisions of special needs education with intellectual disabilities

OpenAIRE

Fujii, Asuka; Ochiai, Toshiro

2011-01-01

The purpose of this study is to investigate the opinions that transition teachers in upper second education division of special school which are requested to themselves on the knowledge and skills needed for transition from school to work. The questionnaires were sent to 574 upper second education divisions of special schools. As the result of statistic analyze, the four domains about the knowledge and skills needed for transition. They were "Needs Assessment", "Coordination" "Job-Coaching" a...

Polydopamine-mediated surface functionalization of electrospun nanofibrous membranes: Preparation, characterization and their adsorption properties towards heavy metal ions

International Nuclear Information System (INIS)

Wu, Chunlin; Wang, Heyun; Wei, Zhong; Li, Chuan; Luo, Zhidong

2015-01-01

Graphical abstract: - Highlights: • A simple and versatile approach to produce PEI-functionalized nanofibers. • Novel PEI-functionalized PVC nanofibrous membrane was prepared. • Adsorption of PVC@PDA and PVC@PDA-PEI nanofibrous membranes for Cu 2+ was tested. • Isotherms, kinetic model and thermodynamic parameters were investigated. • Adsorption mechanism of Cu 2+ on modified membranes was inferred. - Abstract: In this paper, a simple and versatile approach for the fabrication of a polyethyleneimine (PEI)-functionalized nanofibrous membrane utilizing polydopamine (PDA) as a mediator is proposed. The morphology and structure of the PDA-coated and PEI-grafted nanofibrous membranes were confirmed using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. Due to a large specific surface area and long fibrous morphology, the synthesized membranes were used as novel adsorbents for copper ion (Cu 2+ ) removal from aqueous solutions. The adsorption of Cu 2+ was investigated on the synthesized membranes regarding the membrane dosages, initial solution pH values, initial solution concentrations, contact times and temperatures. In addition, the adsorption equilibrium data of PEI-grafted membranes were well fitted with the Langmuir adsorption isotherm, and a maximum adsorption capacity value of 33.59 mg g −1 was determined (while it was 21.94 mg g −1 for the PDA-coated membranes). The thermodynamic parameters indicated that Cu 2+ absorption was a spontaneous and exothermic adsorption process. In addition, XPS peak differentiation imitating analysis permitted the proposal of a copper-amine coordination adsorption mechanism that can be used to explain changes in the adsorption properties compared to PDA coating nanofibrous membranes

The role of IAEA in coordinating research and transferring technology in radiation chemistry and processing of polymers

Energy Technology Data Exchange (ETDEWEB)

Haji-Saeid, M. [International Atomic Energy Agency (IAEA), Wagramer Strasse 5, A-1400 Vienna (Austria)], E-mail: M.Haji-Saeid@iaea.org; Sampa, M.H.; Ramamoorthy, N. [International Atomic Energy Agency (IAEA), Wagramer Strasse 5, A-1400 Vienna (Austria); Gueven, O. [Hacettepe University, Department of Chemistry, Ankara (Turkey); Chmielewski, A.G. [Faculty of Chemical and Process Engineering, Warsaw University of Technology, Warsaw (Poland)

2007-12-15

The IAEA has been playing a significant role in fostering developments in radiation technology in general and radiation processing of polymers in particular, among its Member States (MS) and facilitate know-how/technology transfer to developing MS. The former is usually achieved through coordinated research projects (CRP) and thematic technical meetings, while the latter is mainly accomplished through technical cooperation (TC) projects. Coordinated research projects encourage research on, and development and practical application of, radiation technology to foster exchange of scientific and technical information. The technical cooperation (TC) programme helps Member States to realize their development priorities through the application of appropriate radiation technology. The IAEA has implemented several coordinated research projects (CRP) recently, including one on-going project, in the field of radiation processing of polymeric materials. The CRPs facilitated the acquisition and dissemination of know-how and technology for controlling of degradation effects in radiation processing of polymers, radiation synthesis of stimuli-responsive membranes, hydrogels and absorbents for separation purposes and the use of radiation processing to prepare biomaterials for applications in medicine. The IAEA extends cooperation to well-known international conferences dealing with radiation technology to facilitate participation of talented scientists from developing MS and building collaborations. The IAEA published technical documents, covering the findings of thematic technical meetings (TM) and coordinated research projects have been an important source of valuable practical information.

The role of IAEA in coordinating research and transferring technology in radiation chemistry and processing of polymers

International Nuclear Information System (INIS)

Haji-Saeid, M.; Sampa, M.H.; Ramamoorthy, N.; Gueven, O.; Chmielewski, A.G.

2007-01-01

The IAEA has been playing a significant role in fostering developments in radiation technology in general and radiation processing of polymers in particular, among its Member States (MS) and facilitate know-how/technology transfer to developing MS. The former is usually achieved through coordinated research projects (CRP) and thematic technical meetings, while the latter is mainly accomplished through technical cooperation (TC) projects. Coordinated research projects encourage research on, and development and practical application of, radiation technology to foster exchange of scientific and technical information. The technical cooperation (TC) programme helps Member States to realize their development priorities through the application of appropriate radiation technology. The IAEA has implemented several coordinated research projects (CRP) recently, including one on-going project, in the field of radiation processing of polymeric materials. The CRPs facilitated the acquisition and dissemination of know-how and technology for controlling of degradation effects in radiation processing of polymers, radiation synthesis of stimuli-responsive membranes, hydrogels and absorbents for separation purposes and the use of radiation processing to prepare biomaterials for applications in medicine. The IAEA extends cooperation to well-known international conferences dealing with radiation technology to facilitate participation of talented scientists from developing MS and building collaborations. The IAEA published technical documents, covering the findings of thematic technical meetings (TM) and coordinated research projects have been an important source of valuable practical information

Recurrently connected and localized neuronal communities initiate coordinated spontaneous activity in neuronal networks

Science.gov (United States)

Amin, Hayder; Maccione, Alessandro; Nieus, Thierry

2017-01-01

Developing neuronal systems intrinsically generate coordinated spontaneous activity that propagates by involving a large number of synchronously firing neurons. In vivo, waves of spikes transiently characterize the activity of developing brain circuits and are fundamental for activity-dependent circuit formation. In vitro, coordinated spontaneous spiking activity, or network bursts (NBs), interleaved within periods of asynchronous spikes emerge during the development of 2D and 3D neuronal cultures. Several studies have investigated this type of activity and its dynamics, but how a neuronal system generates these coordinated events remains unclear. Here, we investigate at a cellular level the generation of network bursts in spontaneously active neuronal cultures by exploiting high-resolution multielectrode array recordings and computational network modelling. Our analysis reveals that NBs are generated in specialized regions of the network (functional neuronal communities) that feature neuronal links with high cross-correlation peak values, sub-millisecond lags and that share very similar structural connectivity motifs providing recurrent interactions. We show that the particular properties of these local structures enable locally amplifying spontaneous asynchronous spikes and that this mechanism can lead to the initiation of NBs. Through the analysis of simulated and experimental data, we also show that AMPA currents drive the coordinated activity, while NMDA and GABA currents are only involved in shaping the dynamics of NBs. Overall, our results suggest that the presence of functional neuronal communities with recurrent local connections allows a neuronal system to generate spontaneous coordinated spiking activity events. As suggested by the rules used for implementing our computational model, such functional communities might naturally emerge during network development by following simple constraints on distance-based connectivity. PMID:28749937

Recurrently connected and localized neuronal communities initiate coordinated spontaneous activity in neuronal networks.

Directory of Open Access Journals (Sweden)

Davide Lonardoni

2017-07-01

Full Text Available Developing neuronal systems intrinsically generate coordinated spontaneous activity that propagates by involving a large number of synchronously firing neurons. In vivo, waves of spikes transiently characterize the activity of developing brain circuits and are fundamental for activity-dependent circuit formation. In vitro, coordinated spontaneous spiking activity, or network bursts (NBs, interleaved within periods of asynchronous spikes emerge during the development of 2D and 3D neuronal cultures. Several studies have investigated this type of activity and its dynamics, but how a neuronal system generates these coordinated events remains unclear. Here, we investigate at a cellular level the generation of network bursts in spontaneously active neuronal cultures by exploiting high-resolution multielectrode array recordings and computational network modelling. Our analysis reveals that NBs are generated in specialized regions of the network (functional neuronal communities that feature neuronal links with high cross-correlation peak values, sub-millisecond lags and that share very similar structural connectivity motifs providing recurrent interactions. We show that the particular properties of these local structures enable locally amplifying spontaneous asynchronous spikes and that this mechanism can lead to the initiation of NBs. Through the analysis of simulated and experimental data, we also show that AMPA currents drive the coordinated activity, while NMDA and GABA currents are only involved in shaping the dynamics of NBs. Overall, our results suggest that the presence of functional neuronal communities with recurrent local connections allows a neuronal system to generate spontaneous coordinated spiking activity events. As suggested by the rules used for implementing our computational model, such functional communities might naturally emerge during network development by following simple constraints on distance-based connectivity.

Hybrid membrane contactor system for creating semi-breathing air

Science.gov (United States)

Timofeev, D. V.

2012-02-01

Typically, the equipment to create an artificial climate does not involve changing the composition of the respiratory air. In particular in medical institutions assumes the existence of plant of artificial climate and disinfection in operating rooms and intensive care wards. The use of a hybrid membrane-absorption systems for the generation of artificial atmospheres are improving the respiratory system, blood is enriched or depleted of various gases, resulting in increased stamina, there is a better, faster or slower metabolism, improves concentration and memory. Application of the system contributes to easy and rapid recovery after the operation. By adding a special component, with drug activity, air ionization, and adjust its composition, you can create a special, more favorable for patients with the atmosphere. These factors allow for the treatment and rehabilitation of patients and reduce mortality of heavy patients.

Encouraging ethical considerations - One important task for a national co-ordinator for nuclear waste disposal

International Nuclear Information System (INIS)

Soederberg, O.

1999-01-01

The paper is a brief description of the role and tasks of the Swedish National Co-ordinator for Nuclear Waste Disposal with special regard to one of his activities encouraging ethical considerations in the nuclear waste management issue. Examples are given of ethical considerations which have emerged during discussions among representatives of municipalities which are affected by the current search for a site for a deep geological repository in Sweden for spent nuclear fuel

Membrane fusion by VAMP3 and plasma membrane t-SNAREs

International Nuclear Information System (INIS)

Hu Chuan; Hardee, Deborah; Minnear, Fred

2007-01-01

Pairing of SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) proteins on vesicles (v-SNAREs) and SNARE proteins on target membranes (t-SNAREs) mediates intracellular membrane fusion. VAMP3/cellubrevin is a v-SNARE that resides in recycling endosomes and endosome-derived transport vesicles. VAMP3 has been implicated in recycling of transferrin receptors, secretion of α-granules in platelets, and membrane trafficking during cell migration. Using a cell fusion assay, we examined membrane fusion capacity of the ternary complexes formed by VAMP3 and plasma membrane t-SNAREs syntaxin1, syntaxin4, SNAP-23 and SNAP-25. VAMP3 forms fusogenic pairing with t-SNARE complexes syntaxin1/SNAP-25, syntaxin1/SNAP-23 and syntaxin4/SNAP-25, but not with syntaxin4/SNAP-23. Deletion of the N-terminal domain of syntaxin4 enhanced membrane fusion more than two fold, indicating that the N-terminal domain negatively regulates membrane fusion. Differential membrane fusion capacities of the ternary v-/t-SNARE complexes suggest that transport vesicles containing VAMP3 have distinct membrane fusion kinetics with domains of the plasma membrane that present different t-SNARE proteins

Baryon string model. II. Special solutions of classical three-string equations of motion

International Nuclear Information System (INIS)

Klimenko, S.V.; Kochin, V.N.; Plyushchai, M.S.; Pron'ko, G.P.

1986-01-01

The authors consider special solutions of the classical threestring equations of motion. The basic results needed for construction and analysis of the special solutions are examined. The authors consider very simple solutions in which the three-string node moves with the velocity of light. Singlemode solutions are studied. The graphical packet Atom is used to study and visualize the string dynamics. A new procedure was developed within the packet for graphical representation of many parameter functions. The distinctive feature of these procedures is the large class of functions (including explicit, implicit, and parametric functions) that can be represented by means of parametric, coordinate, and functional isolines

Enhanced Freshwater Production Using Finned-Plate Air Gap Membrane Distillation (AGMD

Directory of Open Access Journals (Sweden)

Perves Bappy Mohammad Jabed

2017-01-01

Full Text Available Air Gap membrane distillation (AGMD, a special type of energy efficient membrane distillation process, is a technology for producing freshwater from waste water. Having some benefits over other traditional processes, this method has been able to draw attention of researchers working in the field of freshwater production technologies. In this study, a basic AGMD system with flat coolant plate has been modified using a specially designed channelled coolant plate of portable size to observe its effect over the production rate and performance of the system. Attempt has been made to increase the amount of distillate flux by using the “fin effect” of the channelled coolant plate. A finned plate have been used instead of a flat coolant plate and experiments were conducted to compare the effect. Coolant temperature and feed temperature of the system have been varied from 10°C to 25°C and 40°C to 70°C respectively. Comparing the data, around 50% to 58% distillate enhancement has been observed for channelled coolant plate. Also, it was seen that the enhancement was higher for higher feed temperatures and coolant temperatures. With these findings, a better performing AGMD module has been introduced to mitigate the scarcity of freshwater.

Overreaching in coordination dynamics therapy in an athlete with a spinal cord injury.

Science.gov (United States)

Schalow, G; Vaher, I; Jaigma, P

2008-03-01

A motocross athlete suffered a clinically complete spinal cord injury (SCI) during competition. Although MRIs (magnetic resonance imaging) showed a complete spinal cord injury at the Thoracic 11/12 levels, surface EMG recordings indicated the survival of few tract fibres across the injury site. Six weeks after the accident the subject began intensive Coordination Dynamics Therapy (CDT) at an up-to-date therapy centre. The subject trained at his physical limits to induce structural and functional repair. Exercising at variable loads between 20 and 200N (on a special CDT and recording device) generated periods of overreaching and super-compensation. By plotting coordination dynamics values (kinesiology), including high-load exertion (200N) and hysteresis curves, periods of overreaching and super-compensation were made graphically visible. It was found that symmetrical improvements of central nervous system (CNS) functioning occurred during overreaching. Improvements in spinal cord functioning were achieved throughout one year of CDT in this chronically injured subject with an almost anatomically complete SCI. It is discussed that the measuring of CNS functions by means of recording coordination dynamics is a powerful and non-invasive tool ideal for exact quantitative and qualitative measurements of improvement (or change) in CNS functioning. Such diagnostics may be of particular importance in sport during training and before competition. Also, coordination dynamics might be used to measure the effects of prolonged exposure to reduced gravitational conditions on CNS functions, such as faced by astronauts.

Luminescent lanthanide coordination polymers

Energy Technology Data Exchange (ETDEWEB)

Ma, L.; Evans, O.R.; Foxman, B.M.; Lin, W.

1999-12-13

One-dimensional lanthanide coordination polymers with the formula Ln(isonicotinate){sub 3}(H{sub 2}O){sub 2} (Ln = Ce, Pr, Nd, Sm, Eu, Tb; 1a-f) were synthesized by treating nitrate or perchlorate salts of Ln(III) with 4-pyridinecarboxaldehyde under hydro(solvo)thermal conditions. Single-crystal and powder X-ray diffraction studies indicate that these lanthanide coordination polymers adopt two different structures. While Ce(III), Pr(III), and Nd(III) complexes adopt a chain structure with alternating Ln-(carboxylate){sub 2}-Ln and Ln-(carboxylate){sub 4}-Ln linkages, Sm(III), Eu(III), and Tb(III) complexes have a doubly carboxylate-bridged infinite-chain structure with one chelating carboxylate group on each metal center. In both structures, the lanthanide centers also bind to two water molecules to yield an eight-coordinate, square antiprismatic geometry. The pyridine nitrogen atoms of the isonicotinate groups do not coordinate to the metal centers in these lanthanide(III) complexes; instead, they direct the formation of Ln(III) coordination polymers via hydrogen bonding with coordinated water molecules. Photoluminescence measurements show that Tb(isonicotinate){sub 3}(H{sub 2}O){sub 2} is highly emissive at room temperature with a quantum yield of {approximately}90%. These results indicate that highly luminescent lanthanide coordination polymers can be assembled using a combination of coordination and hydrogen bonds. Crystal data for 1a: monoclinic space group P2{sub 1}/c, a = 9.712(2) {angstrom}, b = 19.833(4) {angstrom}, c = 11.616(2) {angstrom}, {beta} = 111.89(3){degree}, Z = 4. Crystal data for 1f: monoclinic space group C2/c, a = 20.253(4) {angstrom}, b = 11.584(2) {angstrom}, c = 9.839(2) {angstrom}, {beta} = 115.64(3){degree}, Z = 8.

Membrane interactions and biological activity of antimicrobial peptides from Australian scorpion.

Science.gov (United States)

Luna-Ramírez, Karen; Sani, Marc-Antoine; Silva-Sanchez, Jesus; Jiménez-Vargas, Juana María; Reyna-Flores, Fernando; Winkel, Kenneth D; Wright, Christine E; Possani, Lourival D; Separovic, Frances

2014-09-01

UyCT peptides are antimicrobial peptides isolated from the venom of the Australian scorpion. The activity of the UyCT peptides against Gram positive and Gram negative bacteria and red blood cells was determined. The membrane interactions of these peptides were evaluated by dye release (DR) of the fluorophore calcein from liposomes and isothermal titration calorimetry (ITC); and their secondary structure was determined by circular dichroism (CD). Three different lipid systems were used to mimic red blood cells, Escherichia coli and Staphylococcus aureus membranes. UyCT peptides exhibited broad spectrum antimicrobial activity with low MIC for S. aureus and multi-drug resistant Gram negative strains. Peptide combinations showed some synergy enhancing their potency but not hemolytic activity. The UyCT peptides adopted a helical structure in lipid environments and DR results confirmed that the mechanism of action is by disrupting the membrane. ITC data indicated that UyCT peptides preferred prokaryotic rather than eukaryotic membranes. The overall results suggest that UyCT peptides could be pharmaceutical leads for the treatment of Gram negative multiresistant bacterial infections, especially against Acinetobacter baumanni, and candidates for peptidomimetics to enhance their potency and minimize hemolysis. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova. © 2013.

TECHNICAL COORDINATION

CERN Multimedia

A. Ball

Overview From a technical perspective, CMS has been in “beam operation” state since 6th November. The detector is fully closed with all components operational and the magnetic field is normally at the nominal 3.8T. The UXC cavern is normally closed with the radiation veto set. Access to UXC is now only possible during downtimes of LHC. Such accesses must be carefully planned, documented and carried out in agreement with CMS Technical Coordination, Experimental Area Management, LHC programme coordination and the CCC. Material flow in and out of UXC is now strictly controlled. Access to USC remains possible at any time, although, for safety reasons, it is necessary to register with the shift crew in the control room before going down.It is obligatory for all material leaving UXC to pass through the underground buffer zone for RP scanning, database entry and appropriate labeling for traceability. Technical coordination (notably Stephane Bally and Christoph Schaefer), the shift crew and run ...

Coordination of Conditional Poisson Samples

Directory of Open Access Journals (Sweden)

Grafström Anton

2015-12-01

Full Text Available Sample coordination seeks to maximize or to minimize the overlap of two or more samples. The former is known as positive coordination, and the latter as negative coordination. Positive coordination is mainly used for estimation purposes and to reduce data collection costs. Negative coordination is mainly performed to diminish the response burden of the sampled units. Poisson sampling design with permanent random numbers provides an optimum coordination degree of two or more samples. The size of a Poisson sample is, however, random. Conditional Poisson (CP sampling is a modification of the classical Poisson sampling that produces a fixed-size πps sample. We introduce two methods to coordinate Conditional Poisson samples over time or simultaneously. The first one uses permanent random numbers and the list-sequential implementation of CP sampling. The second method uses a CP sample in the first selection and provides an approximate one in the second selection because the prescribed inclusion probabilities are not respected exactly. The methods are evaluated using the size of the expected sample overlap, and are compared with their competitors using Monte Carlo simulation. The new methods provide a good coordination degree of two samples, close to the performance of Poisson sampling with permanent random numbers.

Keep Meaning in Conversational Coordination

Directory of Open Access Journals (Sweden)

Elena Clare Cuffari

2014-12-01

Full Text Available Coordination is a widely employed term across recent quantitative and qualitative approaches to intersubjectivity, particularly approaches that give embodiment and enaction central explanatory roles. With a focus on linguistic and bodily coordination in conversational contexts, I review the operational meaning of coordination in recent empirical research and related theorizing of embodied intersubjectivity. This discussion articulates what must be involved in treating linguistic meaning as dynamic processes of coordination. The coordination approach presents languaging as a set of dynamic self-organizing processes and actions on multiple timescales and across multiple modalities that come about and work in certain domains (those jointly constructed in social, interactive, high-order sense-making. These processes go beyond meaning at the level that is available to first-person experience. I take one crucial consequence of this to be the ubiquitously moral nature of languaging with others. Languaging coordinates experience, among other levels of behavior and event. Ethical effort is called for by the automatic autonomy-influencing forces of languaging as coordination.

Knee joint kinaesthesia and neuromuscular coordination during three phases of the menstrual cycle in moderately active women.

Science.gov (United States)

Fridén, Cecilia; Hirschberg, Angelica Lindén; Saartok, Tönu; Renström, Per

2006-04-01

An increased incidence of sports related injuries in the premenstrual phase as well as in the menstrual phase of the menstrual cycle has been described. This may be explained by alterations in proprioception and neuromuscular coordination due to hormonal variations. Prospective, within women analysis of knee joint kinesthesia and neuromuscular coordination were performed by repeated measures analysis of variance in three hormonally verified phases of three consecutive menstrual cycles. Thirty-two healthy, moderately active female subjects volunteered to participate in the study. Twenty-five of the subjects performed at least one hormonally verified menstrual cycle. A specially designed device was used to investigate knee joint kinaesthesia and neuromuscular coordination was measured with the square hop test. These tests were carried out in the menstrual phase, ovulation phase and premenstrual phase determined by hormone analyses in three consecutive menstrual cycles. An impaired knee joint kinaesthesia was detected in the premenstrual phase and the performance of square hop test was significantly improved in the ovulation phase compared to the other two phases. The results of this study indicate that the variation of sex hormones in the menstrual cycle has an effect on performance of knee joint kinaesthesia and neuromuscular coordination.

Efficient K+ buffering by mammalian retinal glial cells is due to cooperation of specialized ion channels.

Science.gov (United States)

Nilius, B; Reichenbach, A

1988-06-01

Radial glial (Müller) cells were isolated from rabbit retinae by papaine and mechanical dissociation. Regional membrane properties of these cells were studied by using the patch-clamp technique. In the course of our experiments, we found three distinct types of large K+ conducting channels. The vitread process membrane was dominated by high conductance inwardly rectifying (HCR) channels which carried, in the open state, inward currents along a conductance of about 105 pS (symmetrical solutions with 140 mM K+) but almost no outward currents. In the membrane of the soma and the proximal distal process, we found low conductance inwardly rectifying (LCR) channels which had an open state-conductance of about 60 pS and showed rather weak rectification. The endfoot membrane, on the other hand, was found to contain non-rectifying very high conductance (VHC) channels with an open state-conductance of about 360 pS (same solutions). These results suggest that mammalian Müller cells express regional membrane specializations which are optimized to carry spatial buffering currents of excess K+ ions.

Porphyrin coordination polymer nanospheres and nanorods

Science.gov (United States)

Wang, Zhongchun; Shelnutt, John A.; Medforth, Craig J.

2012-12-04

A porphyrin coordination polymer nanostructure comprising a network of pyridyl porphyrin molecules and coordinating metal ions coordinatively bound through the pyridyl groups. In some embodiments, the porphyrins are metalloporphyrins. A variety of nanostructures are formed by the network polymer, including nanospheres, polygonal nanostructures, nanorods, and nanofibers, depending on a variety of factors including coordination metal ion, porphyrin type, metal of the metalloporphyrin, and degree of agitation during nanostructure formation. Reduction of coordinating metal ions may be used to form metal nanoparticles on the coordination polymer nanostructure.

Characteristics of scientific production in Special Education in Virtual Health Library (VHL: a bibliometric study

Directory of Open Access Journals (Sweden)

Luciana Pizzani

2010-12-01

Full Text Available Objective: To characterize, through bibliometric approach, the scientific literature in this Special Education in the databases of the Virtual Health Library (VHL. The VHL is coordinated by BIREME - Specialized Center of the Pan American Health Organization whose objective is to promote the dissemination and use of scientific information in health. Method: The research methodology was performed by observing the following steps: a literature review on education special and bibliometrics, data collection from the site of BIREME about the presence of special education in the databases, organization, processing and bibliometric analysis of data collected using the software MS Excel and Vantage Point. Results: indicators produced allow signal that the predominant language of scientific production was the Portuguese and the majority of records were written individually, the themes addressed were psychology and developmental psychology. Conclusion: These bibliometric indicators characterizing the state of the art of scientific literature in Special Education at the various bases Data Bireme and also showed a field of interconnections between Health Sciences and Special Education.

Trace Dynamics and a non-commutative special relativity

International Nuclear Information System (INIS)

Lochan, Kinjalk; Singh, T.P.

2011-01-01

Trace Dynamics is a classical dynamical theory of non-commuting matrices in which cyclic permutation inside a trace is used to define the derivative with respect to an operator. We use the methods of Trace Dynamics to construct a non-commutative special relativity. We define a line-element using the Trace over space-time coordinates which are assumed to be operators. The line-element is shown to be invariant under standard Lorentz transformations, and is used to construct a non-commutative relativistic dynamics. The eventual motivation for constructing such a non-commutative relativity is to relate the statistical thermodynamics of this classical theory to quantum mechanics. -- Highlights: → Classical time is external to quantum mechanics. → This implies need for a formulation of quantum theory without classical time. → A starting point could be a non-commutative special relativity. → Such a relativity is developed here using the theory of Trace Dynamics. → A line-element is defined using the Trace over non-commuting space-time operators.

Design of polyelectrolyte multilayer membranes for ion rejection and wastewater effluent treatment

Science.gov (United States)

Sanyal, Oishi

Polyelectrolyte multilayer (PEM) membranes present a special class of nanostructured membranes which have potential applications in a variety of water treatment operations. These membranes are fabricated by the layer-by-layer (LbL) assembly of alternately charged polyelectrolytes on commercial membrane surfaces. A large variety of polyelectrolytes and their varied deposition conditions (pH, number of bilayers etc.) allow very fine tuning of the membrane performance in terms of permeability and rejection. The first part of this thesis is about the application of PEM membranes to the removal of perchlorate ion from water. Being a monovalent ion, it is most effectively removed by a reverse osmosis (RO) membrane. However, these membranes inherently have very low fluxes which lead to high pressure requirements. In our work, we modified the surface of a nanofiltration (NF) membrane by the LbL assembly of oppositely charged polyelectrolytes. The appropriate tuning of the LbL conditions led to the development of a membrane with significantly higher flux than RO membranes but with equivalent perchlorate rejection. This was one of the best trade-offs offered by PEM membranes for monovalent ion rejection as has been reported in literature so far. While PEM membranes have mostly shown great potential in ion-rejection studies, they have seldom been tested for real wastewater effluents. The second part of this thesis, therefore, deals with evaluating the applicability of PEM membranes to treating an electrocoagulation (EC)-treated high strength wastewater. Two types of very commonly used polyelectrolyte combinations were tried out -- one of which was an ionically crosslinked system and the other one was covalently crosslinked. Both the types of PEM membranes showed a high level of COD reduction from the feed stream with higher fluxes than commercial RO membranes. One major challenge in using membranes for wastewater treatment is their fouling propensity. Like many other

Effective dynamics along given reaction coordinates, and reaction rate theory.

Science.gov (United States)

Zhang, Wei; Hartmann, Carsten; Schütte, Christof

2016-12-22

In molecular dynamics and related fields one considers dynamical descriptions of complex systems in full (atomic) detail. In order to reduce the overwhelming complexity of realistic systems (high dimension, large timescale spread, limited computational resources) the projection of the full dynamics onto some reaction coordinates is examined in order to extract statistical information like free energies or reaction rates. In this context, the effective dynamics that is induced by the full dynamics on the reaction coordinate space has attracted considerable attention in the literature. In this article, we contribute to this discussion: we first show that if we start with an ergodic diffusion process whose invariant measure is unique then these properties are inherited by the effective dynamics. Then, we give equations for the effective dynamics, discuss whether the dominant timescales and reaction rates inferred from the effective dynamics are accurate approximations of such quantities for the full dynamics, and compare our findings to results from approaches like Mori-Zwanzig, averaging, or homogenization. Finally, by discussing the algorithmic realization of the effective dynamics, we demonstrate that recent algorithmic techniques like the "equation-free" approach and the "heterogeneous multiscale method" can be seen as special cases of our approach.

Membrane Contact Sites: Complex Zones for Membrane Association and Lipid Exchange

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Quon, Evan; Beh, Christopher T.

2015-01-01

Lipid transport between membranes within cells involves vesicle and protein carriers, but as agents of nonvesicular lipid transfer, the role of membrane contact sites has received increasing attention. As zones for lipid metabolism and exchange, various membrane contact sites mediate direct associations between different organelles. In particular, membrane contact sites linking the plasma membrane (PM) and the endoplasmic reticulum (ER) represent important regulators of lipid and ion transfer. In yeast, cortical ER is stapled to the PM through membrane-tethering proteins, which establish a direct connection between the membranes. In this review, we consider passive and facilitated models for lipid transfer at PM–ER contact sites. Besides the tethering proteins, we examine the roles of an additional repertoire of lipid and protein regulators that prime and propagate PM–ER membrane association. We conclude that instead of being simple mediators of membrane association, regulatory components of membrane contact sites have complex and multilayered functions. PMID:26949334

Liver plasma membranes: an effective method to analyze membrane proteome.

Science.gov (United States)

Cao, Rui; Liang, Songping

2012-01-01

Plasma membrane proteins are critical for the maintenance of biological systems and represent important targets for the treatment of disease. The hydrophobicity and low abundance of plasma membrane proteins make them difficult to analyze. The protocols given here are the efficient isolation/digestion procedures for liver plasma membrane proteomic analysis. Both protocol for the isolation of plasma membranes and protocol for the in-gel digestion of gel-embedded plasma membrane proteins are presented. The later method allows the use of a high detergent concentration to achieve efficient solubilization of hydrophobic plasma membrane proteins while avoiding interference with the subsequent LC-MS/MS analysis.

Subcompartmentalization by cross-membranes during early growth of Streptomyces hyphae

DEFF Research Database (Denmark)

Yagüe, Paula; Willemse, Joost; Koning, Roman I

2016-01-01

Bacteria of the genus Streptomyces are a model system for bacterial multicellularity. Their mycelial life style involves the formation of long multinucleated hyphae during vegetative growth, with occasional cross-walls separating long compartments. Reproduction occurs by specialized aerial hyphae......, which differentiate into chains of uninucleoid spores. While the tubulin-like FtsZ protein is required for the formation of all peptidoglycan-based septa in Streptomyces, canonical divisome-dependent cell division only occurs during sporulation. Here we report extensive subcompartmentalization in young...... vegetative hyphae of Streptomyces coelicolor, whereby 1 μm compartments are formed by nucleic acid stain-impermeable barriers. These barriers possess the permeability properties of membranes and at least some of them are cross-membranes without detectable peptidoglycan. Z-ladders form during the early growth...

Liquid membrane ion-selective electrodes for potentiometric dosage of coper and nickel

Directory of Open Access Journals (Sweden)

MARIA PLENICEANY

2005-02-01

Full Text Available This paper presents experimental and theoretical data regarding the preparation and characterization of three liquid-membrane electrodes, which have not been mentioned in the specialized literature so far. The active substances, the solutions of which in nitrobenzene formed the membranes on a graphite rod, are simple complex combinations of Cu(II and Ni(II ions with an organic ligand belonging to the Schiff base class: N-[2-thienylmethilidene]-2-aminoethanol (TNAHE. The Cu2+ -selective and Ni2+ -selective electrodes were used to determine the copper and nickel ions in aqueous solutions, both by direct potentiometry and by potentiometric titration with EDTA. They were also used for the determination of Cu2+ and Ni2+ ions in industrial waters by direct potentiometry.

Bimanual motor coordination controlled by cooperative interactions in intrinsic and extrinsic coordinates.

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Sakurada, Takeshi; Ito, Koji; Gomi, Hiroaki

2016-01-01

Although strong motor coordination in intrinsic muscle coordinates has frequently been reported for bimanual movements, coordination in extrinsic visual coordinates is also crucial in various bimanual tasks. To explore the bimanual coordination mechanisms in terms of the frame of reference, here we characterized implicit bilateral interactions in visuomotor tasks. Visual perturbations (finger-cursor gain change) were applied while participants performed a rhythmic tracking task with both index fingers under an in-phase or anti-phase relationship in extrinsic coordinates. When they corrected the right finger's amplitude, the left finger's amplitude unintentionally also changed [motor interference (MI)], despite the instruction to keep its amplitude constant. Notably, we observed two specificities: one was large MI and low relative-phase variability (PV) under the intrinsic in-phase condition, and the other was large MI and high PV under the extrinsic in-phase condition. Additionally, using a multiple-interaction model, we successfully decomposed MI into intrinsic components caused by motor correction and extrinsic components caused by visual-cursor mismatch of the right finger's movements. This analysis revealed that the central nervous system facilitates MI by combining intrinsic and extrinsic components in the condition with in-phases in both intrinsic and extrinsic coordinates, and that under-additivity of the effects is explained by the brain's preference for the intrinsic interaction over extrinsic interaction. In contrast, the PV was significantly correlated with the intrinsic component, suggesting that the intrinsic interaction dominantly contributed to bimanual movement stabilization. The inconsistent features of MI and PV suggest that the central nervous system regulates multiple levels of bilateral interactions for various bimanual tasks. © 2015 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and

Connecting people and information: how an African special library is building bridges

CSIR Research Space (South Africa)

Halland, Y

2009-04-30

Full Text Available : How an African Special Library is Building Bridges Yvonne Halland, BA Library Science Strategic Information Resources Coordinator CSIR Information Services Pretoria, South Africa Member, Science & Technology Division Noxolo Mniki... delivery, information literacy training and knowledge management. Although the CSIR library was at one time regarded as the top science & technology library in the country, the upward spiralling costs of information resources over the last twenty...

[Civilian-military coordination].

Science.gov (United States)

de Montravel, G

2002-01-01

Current humanitarian emergencies create complex, mutidimensional situations that stimulate simultaneous responses from a wide variety of sources including governments, non-governmental organizations (NGO), United Nations agencies, and private individuals. As a result, it has become essential to establish a coherent framework in which each actor can contribute promptly and effectively to the overall effort. This is the role of the United Nations Office for the Coordination of Humanitarian Affairs. Regardless of the circumstances and level of coordination, cooperation and collaboration between humanitarian and military personnel, it is necessary to bear in mind their objectives. The purpose of humanitarian action is to reduce human suffering. The purpose of military intervention is to stop warfare. The author of this article will discuss the three major obstacles to civilian-military coordination (strategic, tactical, and operational). Operations cannot be conducted smoothly and differences cannot be ironed out without mutual respect between the two parties, an explicit definition of their respective duties and responsibilities, a clear understanding of their cultural differences, and the presence of an organization and facilities for coordination and arbitrage by a neutral referee.

Membrane Biophysics

CERN Document Server

Ashrafuzzaman, Mohammad

2013-01-01

Physics, mathematics and chemistry all play a vital role in understanding the true nature and functioning of biological membranes, key elements of living processes. Besides simple spectroscopic observations and electrical measurements of membranes we address in this book the phenomena of coexistence and independent existence of different membrane components using various theoretical approaches. This treatment will be helpful for readers who want to understand biological processes by applying both simple observations and fundamental scientific analysis. It provides a deep understanding of the causes and effects of processes inside membranes, and will thus eventually open new doors for high-level pharmaceutical approaches towards fighting membrane- and cell-related diseases.

Polyurethane Nanofiber Membranes for Waste Water Treatment by Membrane Distillation

OpenAIRE

Jiříček, T.; Komárek, M.; Lederer, T.

2017-01-01

Self-sustained electrospun polyurethane nanofiber membranes were manufactured and tested on a direct-contact membrane distillation unit in an effort to find the optimum membrane thickness to maximize flux rate and minimize heat losses across the membrane. Also salt retention and flux at high salinities up to 100 g kg−1 were evaluated. Even though the complex structure of nanofiber layers has extreme specific surface and porosity, membrane performance was surprisingly predictable; the highest ...

Targeting the plasma membrane of neoplastic cells through alkylation: a novel approach to cancer chemotherapy.

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Trendowski, Matthew; Fondy, Thomas P

2015-08-01

Although DNA-directed alkylating agents and related compounds have been a mainstay in chemotherapeutic protocols due to their ability to readily interfere with the rapid mitotic progression of malignant cells, their clinical utility is limited by DNA repair mechanisms and immunosuppression. However, the same destructive nature of alkylation can be reciprocated at the cell surface using novel plasma membrane alkylating agents. Plasma membrane alkylating agents have elicited long term survival in mammalian models challenged with carcinomas, sarcomas, and leukemias. Further, a specialized group of plasma membrane alkylating agents known as tetra-O-acetate haloacetamido carbohydrate analogs (Tet-OAHCs) potentiates a substantial leukocyte influx at the administration and primary tumor site, indicative of a potent immune response. The effects of plasma membrane alkylating agents may be further potentiated through the use of another novel class of chemotherapeutic agents, known as dihydroxyacetone phosphate (DHAP) inhibitors, since many cancer types are known to rely on the DHAP pathway for lipid synthesis. Despite these compelling data, preliminary clinical trials for plasma membrane-directed agents have yet to be considered. Therefore, this review is intended for academics and clinicians to postulate a novel approach of chemotherapy; altering critical malignant cell signaling at the plasma membrane surface through alkylation, thereby inducing irreversible changes to functions needed for cell survival.

F-BAR family proteins, emerging regulators for cell membrane dynamic changes-from structure to human diseases.

Science.gov (United States)

Liu, Suxuan; Xiong, Xinyu; Zhao, Xianxian; Yang, Xiaofeng; Wang, Hong

2015-05-09

Eukaryotic cell membrane dynamics change in curvature during physiological and pathological processes. In the past ten years, a novel protein family, Fes/CIP4 homology-Bin/Amphiphysin/Rvs (F-BAR) domain proteins, has been identified to be the most important coordinators in membrane curvature regulation. The F-BAR domain family is a member of the Bin/Amphiphysin/Rvs (BAR) domain superfamily that is associated with dynamic changes in cell membrane. However, the molecular basis in membrane structure regulation and the biological functions of F-BAR protein are unclear. The pathophysiological role of F-BAR protein is unknown. This review summarizes the current understanding of structure and function in the BAR domain superfamily, classifies F-BAR family proteins into nine subfamilies based on domain structure, and characterizes F-BAR protein structure, domain interaction, and functional relevance. In general, F-BAR protein binds to cell membrane via F-BAR domain association with membrane phospholipids and initiates membrane curvature and scission via Src homology-3 (SH3) domain interaction with its partner proteins. This process causes membrane dynamic changes and leads to seven important cellular biological functions, which include endocytosis, phagocytosis, filopodium, lamellipodium, cytokinesis, adhesion, and podosome formation, via distinct signaling pathways determined by specific domain-binding partners. These cellular functions play important roles in many physiological and pathophysiological processes. We further summarize F-BAR protein expression and mutation changes observed in various diseases and developmental disorders. Considering the structure feature and functional implication of F-BAR proteins, we anticipate that F-BAR proteins modulate physiological and pathophysiological processes via transferring extracellular materials, regulating cell trafficking and mobility, presenting antigens, mediating extracellular matrix degradation, and transmitting

Genomic analysis indicates the presence of an asymmetric bilayer outer membrane in Planctomycetes and Verrucomicrobia

Directory of Open Access Journals (Sweden)

Daan R Speth

2012-08-01

Full Text Available Bacteria of the phylum Planctomycetes are of special interest for the study of compartmental cellular organization. Members of this phylum share a very unusual prokaryotic cell plan, featuring several membrane-bound compartments. Recently, it was shown that this cellular organization might extend to certain members of the phylum Verrucomicrobia. The Planctomycete cell plan has been defined as featuring a proteinaceous cell wall, a cytoplasmic membrane surrounding the paryphoplasm and an intracytoplasmic membrane defining the riboplasm. So far it was presumed that Planctomycetes did not have an asymmetric bilayer outer membrane as observed in Gram-negative bacteria. However, recent work on outer membrane biogenesis has provided several marker genes in the outer membrane protein (OMP assembly and the lipopolysaccharide (LPS insertion complexes. Additionally, advances in computational prediction of OMPs provided new tools to perform more accurate genomic screening for such proteins.Here we searched all 22 Planctomycetes and Verrucomicrobia genomes available in Genbank, plus the recently published genome of ‘Candidatus Scalindua profunda’, for markers of outer membrane biogenesis and OMPs. We were able to identify the key components of LPS insertion, OMP assembly and at least eight OMPs in all genomes tested. Additionally, we have analyzed the transcriptome and proteome data of the Planctomycetes ‘Candidatus Kuenenia stuttgartiensis’ and ‘Ca. S. profunda’ and could confirm high expression of several predicted OMPs, including the biomarkers of outer membrane biogenesis.

Nanodisc-solubilized membrane protein library reflects the membrane proteome

OpenAIRE

Marty, Michael T.; Wilcox, Kyle C.; Klein, William L.; Sligar, Stephen G.

2013-01-01

The isolation and identification of unknown membrane proteins offers the prospect of discovering new pharmaceutical targets and identifying key biochemical receptors. However, interactions between membrane protein targets and soluble ligands are difficult to study in vitro due to the insolubility of membrane proteins in non-detergent systems. Nanodiscs, nanoscale discoidal lipid bilayers encircled by a membrane scaffold protein belt, have proven to be an effective platform to solubilize membr...

Impact of sludge flocs on membrane fouling in membrane bioreactors

DEFF Research Database (Denmark)

Christensen, Morten Lykkegaard; Niessen, Wolfgang; Jørgensen, Mads Koustrup

Membrane bioreactors (MBR) are widely used for wastewater treatment, but membrane fouling reduces membrane performance and thereby increases the cost for membranes and fouling control. Large variation in filtration properties measured as flux decline was observed for the different types of sludges....... Further, the flux could partly be reestablished after the relaxation period depending on the sludge composition. The results underline that sludge properties are important for membrane fouling and that control of floc properties, as determined by the composition of the microbial communities...... and the physico-chemical properties, is an efficient method to reduce membrane fouling in the MBR. High concentration of suspended extracellular substances (EPS) and small particles (up to 10 µm) resulted in pronounced fouling propensity. The membrane fouling resistance was reduced at high concentration...

Membrane Fluidity Changes, A Basic Mechanism of Interaction of Gravity with Cells?

Science.gov (United States)

Kohn, Florian; Hauslage, Jens; Hanke, Wolfgang

2017-10-01

All life on earth has been established under conditions of stable gravity of 1g. Nevertheless, in numerous experiments the direct gravity dependence of biological processes has been shown on all levels of organization, from single molecules to humans. According to the underlying mechanisms a variety of questions, especially about gravity sensation of single cells without specialized organelles or structures for gravity sensing is being still open. Biological cell membranes are complex structures containing mainly lipids and proteins. Functional aspects of such membranes are usually attributed to membrane integral proteins. This is also correct for the gravity dependence of cells and organisms which is well accepted since long for a wide range of biological systems. However, it is as well established that parameters of the lipid matrix are directly modifying the function of proteins. Thus, the question must be asked, whether, and how far plain lipid membranes are affected by gravity directly. In principle it can be said that up to recently no real basic mechanism for gravity perception in single cells has been presented or verified. However, it now has been shown that as a basic membrane parameter, membrane fluidity, is significantly dependent on gravity. This finding might deliver a real basic mechanism for gravity perception of living organisms on all scales. In this review we summarize older and more recent results to demonstrate that the finding of membrane fluidity being gravity dependent is consistent with a variety of published laboratory experiments. We additionally point out to the consequences of these recent results for research in the field life science under space condition.

47 CFR 95.1113 - Frequency coordinator.

Science.gov (United States)

2010-10-01

... SERVICES Wireless Medical Telemetry Service (WMTS) General Provisions § 95.1113 Frequency coordinator. (a) The Commission will designate a frequency coordinator(s) to manage the usage of the frequency bands for the operation of medical telemetry devices. (b) The frequency coordinator shall (1) Review and...

Mitochondrial AAA proteases--towards a molecular understanding of membrane-bound proteolytic machines.

Science.gov (United States)

Gerdes, Florian; Tatsuta, Takashi; Langer, Thomas

2012-01-01

Mitochondrial AAA proteases play an important role in the maintenance of mitochondrial proteostasis. They regulate and promote biogenesis of mitochondrial proteins by acting as processing enzymes and ensuring the selective turnover of misfolded proteins. Impairment of AAA proteases causes pleiotropic defects in various organisms including neurodegeneration in humans. AAA proteases comprise ring-like hexameric complexes in the mitochondrial inner membrane and are functionally conserved from yeast to man, but variations are evident in the subunit composition of orthologous enzymes. Recent structural and biochemical studies revealed how AAA proteases degrade their substrates in an ATP dependent manner. Intersubunit coordination of the ATP hydrolysis leads to an ordered ATP hydrolysis within the AAA ring, which ensures efficient substrate dislocation from the membrane and translocation to the proteolytic chamber. In this review, we summarize recent findings on the molecular mechanisms underlying the versatile functions of mitochondrial AAA proteases and their relevance to those of the other AAA+ machines. Copyright © 2011 Elsevier B.V. All rights reserved.

Pretreatment and Membrane Hydrophilic Modification to Reduce Membrane Fouling

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Huaqiang Chu

2013-09-01

Full Text Available The application of low pressure membranes (microfiltration/ultrafiltration has undergone accelerated development for drinking water production. However, the major obstacle encountered in its popularization is membrane fouling caused by natural organic matter (NOM. This paper firstly summarizes the two factors causing the organic membrane fouling, including molecular weight (MW and hydrophilicity/hydrophobicity of NOM, and then presents a brief introduction of the methods which can prevent membrane fouling such as pretreatment of the feed water (e.g., coagulation, adsorption, and pre-oxidation and membrane hydrophilic modification (e.g., plasma modification, irradiation grafting modification, surface coating modification, blend modification, etc.. Perspectives of further research are also discussed.

40 CFR 109.6 - Coordination.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Coordination. 109.6 Section 109.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS CRITERIA FOR STATE, LOCAL AND REGIONAL OIL REMOVAL CONTINGENCY PLANS § 109.6 Coordination. For the purposes of coordination...

Addressing the oral healthcare needs of special needs children: pediatric nurses' self-perceived effectiveness.

Science.gov (United States)

Parish, Carrigan L; Singer, Richard; Abel, Stephen; Metsch, Lisa R

2014-01-01

To examine the oral health knowledge and practices of pediatric nurses who coordinate healthcare services for special needs children and to identify those factors that influenced their perceived effectiveness in managing their patients' oral health needs. Self-reported data were collected from 376 nurses employed at Children's Medical Services who responded to an online survey. Likert scale scores were used to specifically assess the nurses' perceived effectiveness in addressing the oral health needs of special needs children. Characteristics significantly associated with special needs pediatric nurses who described themselves as "effective or very effective" included: the self-perception of being very knowledgeable about basic oral health, receiving four or more hours of continuing education training, and securing dental appointments for the majority of their pediatric special needs patients with minimal waiting times. Findings reveal that oral health knowledge significantly influenced nurses' perceived effectiveness in addressing the oral health needs of special needs children, as well as their ability to secure timely dental appointments. These results support the need to incorporate oral health education into nursing curricula and expand upon the dental workforce available and willing to treat disabled patients. © 2013 Special Care Dentistry Association and Wiley Periodicals, Inc.

The National Coordinated Research Programme for Air Quality. Another choice for clean air

International Nuclear Information System (INIS)

Van Giezen, M.; Havinga, A.; De Boer, H.

2009-01-01

On August 1st 2009 the National Coordinated Research Programme for Air quality (NSL in Dutch) entered into operation. This programme must help improve air quality such that it meets the European standards. At the same time the deadlock between environment and space is also solved. A special approach has been chosen for this purpose, which is based on a common interest of the State, provinces and local authorities. It was an intensive and interesting process. The annual monitoring will have to show whether or not the NSL will meet its objectives. [nl

Regulation of the basement membrane by epithelia generated forces

Science.gov (United States)

Tanner, Kandice