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Día Internacional de la Mujer 2011.

Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" Visita la página de Madres Solas Aquí. Más »

Entrega de Silla de Ruedas.

Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" Visita la página de Madres Solas Aquí. Más »

Compartiendo con nuestras socias y socios de la tercera edad de Molino Abajo, Temoaya, Estado de México.

Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" Visita la página de Madres Solas Aquí. Más »

Visita la página de “Código Ayuda A.C.” Aquí

Entrega de Reconocimiento por la AMS a la labor de Gabriela Goldsmith Presidenta de \\\\\\\"Código Ayuda A.C.” Más »

Día de la Niñez 2011 con nuestras socias y socios de San Lorenzo Tepaltitlán, Toluca, Estado de México.

Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" Visita la página de Madres Solas Aquí. Más »

Entrega de Silla de Ruedas.

Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" Visita la página de Madres Solas Aquí. Más »

“Yo Me Declaro Defensor” de los Defensores de Derechos Humanos

Participación en la campaña “Yo Me Declaro Defensor” de los Defensores de Derechos Humanos por la Alta Comisionada de los Derechos Humanos de la ONU Navy Pillay. Más »

Entrega de Reconocimiento al Lic. Enrique Peña Nieto por su apoyo como gobernador a los grupos vulnerables de nuestra Asociación.

Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" Visita la página de Madres Solas Aquí. Más »

Compartiendo con nuestras socias y socios de la tercera edad en Molino Abajo, Temoaya, Estado de México.

Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" ¡Visita la página de Madres Solas Aquí! Más »

Compartiendo con nuestras socias y socios de la tercera edad en Molino Abajo, Temoaya, Estado de México.

Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" ¡Visita la página de Madres Solas Aquí! Más »

Compartiendo con nuestras socias y socios de la tercera edad en Molino Abajo, Temoaya, Estado de México.

Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" ¡Visita la página de Madres Solas Aquí! Más »

Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" ¡Visita la página de Madres Solas Aquí! Más »

Thelma Dorantes Autora y Actriz principal de la obra de Teatro \\\\

Visita de Thelma Dorantes a las oficina de la Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" en Toluca, Estado de México. Más »

Thelma Dorantes Autora y Actriz principal de la obra de Teatro \\\\

Visita de Thelma Dorantes a las oficina de la Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" en Toluca, Estado de México. Más »

Thelma Dorantes Autora y Actriz principal de la obra de Teatro \\\\

Visita de Thelma Dorantes a las oficina de la Asociación de Madres Solteras y Grupos Vulnerables para el Desarrollo Social \\\\\\\"Por un Trato más digno Yo Madre Soltera Aquí Estoy A.C.\\\\\\\" en Toluca, Estado de México. Más »

Premio Nacional del Trabajo 2012.

Entrega a los trabajadores de la Dirección de Organización y Desarrollo Administrativo de la Universidad Autónoma del Estado de México del Premio Nacional del Trabajo 2012 por la Secretaría de Trabajo y Previsión Social del Gobierno de México. Más »

 

Metabolic phasing of anoxic-PDBR for high rate treatment of azo dye wastewater

This NEWS was origynally shared on Sutesuaem Universities News

Fuente: Science Direct

Journal of Hazardous Materials
Research Paper

Highlights

Strategic induction of air aided the complete mineralization of azo dye.

Facultative bacteria showed robust activity with varying microenvironments.

Enhancement in overall performance of anoxic PDBR was achieved in AMPIII strategy.

Higher azo reductase and dehydrogenase activity correlate well with dye removal.

Abstract

The treatment of azo dye wastewater was studied in a periodic discontinuous batch reactor (PDBR) at high loading condition (1250 mg/l) under anoxic microenvironments. PDBR performance was evaluated by varying the time period of aerobic microenvironment during the cycle operation [before multiphasing (BMP; Control), 0.014; after multiphasing (AMP): AMPI, 0.84; AMPII, 0.73; AMPIII, 0.65]. Induction of air in anoxic-PDBR facilitated the simultaneous oxidation and reduction conditions and thus resulted higher dye removal efficiency with AMPIII strategy (65%) followed by AMPII (59.4%) and AMPI (54.4%) than the corresponding control operation (BMP: 49.4%). Relatively higher azo reductase enzyme activity was documented with AMP than corresponding BMP operation correlating well with azo dye decolorization. UV– UV–Significant transformational changes of azo dye peaks (618 nm) were documented before and after multiphase operations. Cyclic voltammogram profiles depicted increment in redox catalytic currents during AMPIII operation and also supports the involvement of reducing equivalents towards the dye removal. Derivatives of voltammograms illustrated the involvement of various redox mediators viz., cytochrome-C, quinones, Fumarate/Succinate, Fe(CN)63−/Fe(CN)64−, and flavoproteins. Flexibility in phasing the multiple microenvironments in single bioreactor (PDBR) provides new insights in embodying the required capabilities to treat the recalcitrant azo dye wastewater especially at higher dye load operations

Graphical abstract

Keywords

Periodic discontinuous batch reactor

Multiphasing

Dye wastewater: Redox mediators

Azo reductase

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© 2017 Elsevier B.V. All rights reserved.

A minimum adjustment cost feedback mechanism based consensus model for group decision making under social network with distributed linguistic trust

This NEWS was origynally shared on Sutesuaem Universities News

Fuente: Science Direct

Information Fusion

Highlights

A new consensus model for social network group decision making problems is presented.

A novel minimum adjustment cost feedback mechanism to generate recommendations is defined.

A social network analysis methodology to represent and model trust degrees is defined.

Trust degrees are used as importance degrees to characterize the value of experts.

Abstract

A theoretical feedback mechanism framework to model consensus in social network group decision making (SN-GDM) is proposed with following two main components: (1) the modelling of trust relationship with linguistic information; and (2) the minimum adjustment cost feedback mechanism. To do so, a distributed linguistic trust decision making space is defined, which includes the novel concepts of distributed linguistic trust functions, expectation degree, uncertainty degrees and ranking method. Then, a social network analysis (SNA) methodology is developed to represent and model trust relationship between a networked group, and the trust in-degree centrality indexes are calculated to assign an importance degree to the associated user. To identify the inconsistent users, three levels of consensus degree with distributed linguistic trust functions are calculated. Then, a novel feedback mechanism is activated to generate recommendation advices for the inconsistent users to increase the group consensus degree. Its novelty is that it produces the boundary feedback parameter based on the minimum adjustment cost optimisation model. Therefore, the inconsistent users are able to reach the threshold value of group consensus incurring a minimum modification of their opinions or adjustment cost, which provides the optimum balance between group consensus and individual independence. Finally, after consensus has been achieved, a ranking order relation for distributed linguistic trust functions is constructed to select the most appropriate alternative of consensus.

Keywords

Group decision making

Feedback mechanism

Minimum adjustment optimization model

Consensus

Social network analysis

Distributed linguistic trust

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© 2017 Elsevier B.V. All rights reserved.

The effect of Nanocrystalline cellulose/Gum Arabic conjugates in crosslinked membrane for antibacterial, chlorine resistance and boron removal performance

This NEWS was origynally shared on Sutesuaem Universities News

Fuente: Science Direct

Nanocrystalline cellulose/Gum Arabic conjugated membranes are prepared.

Nanocrystalline cellulose is synthesized from microcrystalline cellulose via acid hydrolysis process.

The activity of Nanocrystalline cellulose/Gum Arabic conjugates is studied for hazardous salt (Boron) removal.

The rejection efficiency of boron reaches 92.4%.

Gum Arabic can effectively hinder the E.coli attachment as both are negatively charged.

Optimal pension fund management in a jump–diffusion environment: Theoretical and empirical studies

This NEWS was origynally shared on Sutesuaem Universities News

Fuente: Science Direct

Journal of Computational and Applied Mathematics

Abstract

This paper considers a theoretical and an empirical study of an optimal pension fund in an inflation environment in which the consumption–portfolio selection problem of an investor who faces both diffusion and jump risks was analyzed. Since the time horizon of a pension fund management is relatively long, we put into consideration four background risks which include inflation, interest rate, investment and income risks. A pension plan member (PPM) is expected to contribute continuously a time-consistent proportion of his income into the scheme. These contributions are invested into a market that is characterized by multiple risk-free assets (which include riskless bonds and bank deposit accounts), stocks and index bonds. The risky assets (stocks and index bonds), interest rates and income process are assumed to follow a jump–diffusion process. Real wealth for the plan member is considered. The resulting Hamilton–Jacobi–Bellman equation was solved using dynamic programming approach. From which, the optimal consumption and optimal investments with jump risks were obtained. Empirical data were collected from Nigeria Stock Exchange; National Bureau of Statistics, Nigeria; and Bursary Department, University of Benin, Nigeria. The analyses of the data were carried out using SPSS package in order to obtain the needed information for the parameters in our derived models. The resulting models for optimal portfolio and consumption were solved using MatLab and Mathematica software. We found that inflation, interest rate and income risks have significant influence on the investor’s portfolio values in the risky assets. We also found that as the risk averse coefficient increases, consumption increases and vice versa. Furthermore, we found that an increase in income can lead to an increase in the portfolio risks and vice versa.

JEL classification

G11

G12

C02

C22

C61

Keywords

Optimal pension fund

Inflation environment

Consumption

Jump risks

Income risk

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© 2017 Elsevier B.V. All rights reserved.

Harvard research reports major forest loss in New England

This NEWS was origynally shared on Sutesuaem Universities News

Fuente: Harvard Gazette

http://harvardgazette.files.wordpress.com/2017/09/forest-development_605.jpg

New England is in danger of squandering its conservation “second chance,” according to the authors of a new Harvard Forest report.

The region, heavily deforested in colonial days, is today one of the most densely wooded in the world, thanks to forests that regenerated over the past 150 years as farms were abandoned for city life.

But that reforestation has peaked, and New England is now losing 65 acres of forest to development each day, the report says. In addition, funding for land conservation has fallen 50 percent since 2008, and the acreage conserved annually is also down, falling more than sixfold since the early 2000s, from 333,000 acres a year to about 50,000 acres a year since 2010.

“Peak forest cover is over in New England,” said Jonathan Thompson, a senior scientist at Harvard Forest and one of the report’s 31 authors. “For more than 150 years, forests expanded and regrew. That history is how we gained the status as among the most populated and most forested regions in the world.”
Modified from Foster and Aber (2004) with additional data from USFS FIA state reports. Foster, D. R. and J. D. Aber. 2004. Forests in time. Yale University Press, New Haven, CT.
Thompson said that about 88 percent of New England is forest or farmland, but that development — 50 percent of which is residential — amounts to a “hard, permanent” deforestation that removes the land from natural uses for the foreseeable future.

“If current rates continue, New England will lose another 1.2 million acres by the year 2060 — that’s an area nearly twice as big as Rhode Island,” he said.

While climate change threatens to alter natural communities and favors some species over others, development eliminates ecosystems altogether, Thompson said. In addition, he said, land is our biggest asset in fighting climate change, with growing trees locking up carbon and natural areas buffering the effects.

The report, “Wildlands and Woodlands, Farmlands and Communities,” calls for tripling conservation efforts across the region, with the aim of setting aside 30 million acres of forest covering 70 percent of New England, as well as all of its remaining farmland. Ten percent of the conserved acreage would be set aside as wildland, while the rest would be managed sustainably for wood products and other forest-related benefits.

In order to achieve that level of conservation, the report’s authors call for increased public funding, integrating land conservation with urban and municipal planning, and ensuring that land dedicated for economic development is used as efficiently as possible.
Conserved forests like those around the Quabbin Reservoir provide clean drinking water to millions of New England residents without the need for filtration plants. Photo by Clarisse Hart
Harvard Forest Director David Foster, the report’s senior author, sees cities and towns as partners in such efforts. He offered the example of former mill towns that have seen redevelopment of industrial buildings, creating desirable residential areas that are near transportation and other infrastructure.

Despite the negative trends noted in the report, Foster said there are reasons for optimism. The region has a long history of support for land conservation, and in recent years regional conservation partnerships have multiplied. State and municipal efforts have also been expanding. For example, the Massachusetts Community Preservation Act allows towns to add a surtax to land transfers and direct the revenue to preservation. The program is voluntary, but 11 towns signed on last year, bringing the total to 173, nearly half the state’s 351 communities.

Another positive factor, Foster said, is that conservation opportunities abound. Conservation organizations are regularly contacted by landowners interested in setting aside land or protecting it from development. The problem, Foster said, is that for many of these individuals, much of the wealth is tied up in the land, which makes the development of innovative programs and identifying new funds important.

“There are more opportunities than we can handle,” Foster said.

Foster noted growing recognition of the benefits of conserving forests, creating opportunities for an array of partnerships — such as with health care organizations that recognize the benefits of natural areas — that may not have been possible in the past.

“The capacity for conservation in New England is unrivaled in the world,” he said. “We know that there are huge emerging opportunities for land protection and we know that when similar opportunities occurred in the past, the states, local municipalities, and conservation organizations collaborated to seize on these.”

Neutrino facility could change understanding of the universe

This NEWS was origynally shared on Sutesuaem Universities News

Fuente: University of Oxford News

The University of Oxford’s Department of Physics will play a pivotal role in a flagship global science facility that could change our understanding of the universe.
The UK is investing £65million in the initiative, which will be based in the United States and could secure Britain’s position as the international research partner of choice.

UK Universities and Science Minister Jo Johnson today signed the agreement with the US Energy Department to invest the sum in the Long-Baseline Neutrino Facility (LBNF) and the Deep Underground Neutrino Experiment (DUNE). DUNE will study the properties of mysterious particles called neutrinos, which could help explain more about how the universe works and why matter exists at all.

The UK’s Science and Technology Facilities Council (STFC) will manage the UK’s investment in the international facility, giving UK scientists and engineers the chance to take a leading role in the management and development of the DUNE far detector and the LBNF beam line and associated PIP-II accelerator development.

The LBNF will be the world’s most intense high-energy neutrino beam. It will fire neutrinos 1300 km from Fermilab in Illinois towards the 70,000 ton DUNE detector at the Sanford Underground Research Facility (SURF) in South Dakota in order to study neutrino oscillations. Once constructed, it will operate for at least 15 years undertaking a broad and exciting science programme.

Professor Ian Shipsey, Head of Particle Physics at Oxford, said: ‘Neutrinos are the second most common particle in the universe and yet today we know more about the recently discovered Higgs particle than we do about neutrinos.  Much of what we do know, however, has been painstakingly pieced together over many years in very clever neutrino experiments in which Oxford physicists have played a leading role.

‘I am thrilled that the agreement that has just been signed between the US and UK  will enable many UK physicists including my brilliant Oxford colleagues and neutrino experts Professor Giles Barr and Professor Alfons Weber to continue to learn more about neutrinos through participation in what is arguably the most ambitious experiment yet mounted to study them’.

Prof. Alfons Weber, the UK Principal Investigator of the project, said: ‘This is a dream come true. We have been working hard over the last few years to develop the techniques needed to be able to build this experiment. Our partners in the north have concentrated on the readout structures, while we in Oxford have taken the lead in the development of the data acquisition system.

‘We have an excellent team that came up with innovative solutions. These detectors have to be huge as neutrinos interact so rarely. You have to optimise the cost so that we can build the biggest detector possible, but at the same time it has to be sensitive enough to be able to still measure these feeble interactions. I am now organising a design study to specify the near detector, which is an essential tool to characterise the neutrino beam and interactions.’

Prof. Giles Barr has led the data acquisition design group of the international project for the last four years. Under his leadership, the collaboration has developed the concepts to handle the large data set from this 70,000 ton detector. He has overseen the first implementation and tests and is now heavily involved in commissioning the latest full-scale prototype at a test beam at CERN. Commenting on his role in the experiment, he said: ‘It is exciting working with people both locally and internationally who have the expertise and imagination to squeeze the maximum performance out of some very hi-tech, modern electronics components. 

‘The detector will generate over a TeraByte of raw data every second for more that 20 years and it is our job to find and keep the parts of the data that show the neutrinos interacting in the detector – “the needle in the haystack’.

The UK research community is already a major contributor to the DUNE collaboration, with 14 UK universities and two STFC laboratories providing essential expertise and components to the experiment and facility. This ranges from the high-power neutrino production target, the readout planes and data acquisitions systems to the reconstruction software.

One aspect DUNE scientists will look for is the differences in behaviour between neutrinos and their antimatter counterparts, antineutrinos, which could give us clues as to why we live in a matter-dominated universe – in other words, why we are all here, instead of having been annihilated just after the Big Bang. DUNE will also watch for neutrinos produced when a star explodes, which could reveal the formation of neutron stars and black holes, and will investigate whether protons live forever or eventually decay, bringing us closer to fulfilling Einstein’s dream of a grand unified theory.

The DUNE experiment will attract students and young scientists from around the world, helping to foster the next generation of leaders in the field and to maintain the highly skilled scientific workforce worldwide.

Green algae could hold clues for engineering faster-growing crops

This NEWS was origynally shared on Sutesuaem Universities News

Fuente: Princeton University Science and Technology Stories

https://www.princeton.edu/sites/default/files/styles/rss_enclosure_image/public/images/2017/09/Screenshot_video.jpg?itok=gAHgZXBZ
Two new Princeton-led studies provide a detailed look at an essential part of algae’s growth machinery, with the eventual goal of applying this knowledge to improving the growth of crops. In this image, the researchers used a technique called cryo-electron tomography to image an algal structure called the pyrenoid, which concentrates carbon dioxide to make it more readily available for photosynthetic enzymes (purple). The yellow tubules inside the green tubes are thought to bring carbon and other materials into the pyrenoid.

Two new studies of green algae — the scourge of swimming pool owners and freshwater ponds — have revealed new insights into how these organisms siphon carbon dioxide from the air for use in photosynthesis, a key factor in their ability to grow so quickly. Understanding this process may someday help researchers improve the growth rate of crops such as wheat and rice.

In the studies published this week in the journal Cell, the Princeton-led team reported the first detailed inventory of the cellular machinery — located in an organelle known as the pyrenoid —  that algae use to collect and concentrate carbon dioxide. The researchers also found that the pyrenoid, long thought to be a solid structure, actually behaves like a liquid droplet that can dissolve into the surrounding cellular medium when the algal cells divide.

“Understanding how algae can concentrate carbon dioxide is a key step toward the goal of improving photosynthesis in other plants,” said Martin Jonikas, an assistant professor of molecular biology at Princeton and leader of the studies, which included collaborators at the Max Planck Institute of Biochemistry in Germany and the Carnegie Institution for Science on the Stanford University campus. “If we could engineer other crops to concentrate carbon, we could address the growing world demand for food,” Jonikas said.

Aquatic algae and a handful of other plants have developed carbon-concentrating mechanisms that boost the rate of photosynthesis, the process by which plants turn carbon dioxide and sunlight into sugars for growth. All plants use an enzyme called Rubisco to “fix” carbon dioxide into sugar that can be used or stored by the plant.

Algae have an advantage over many land plants because they cluster the Rubisco enzymes inside the pyrenoid, where the enzymes encounter high concentrations of carbon dioxide pumped in from the air. Having more carbon dioxide around allows the Rubisco enzymes to work faster.

In the first of the two studies reported this week, the researchers conducted a sweeping search for proteins involved in the carbon-concentrating mechanism of an algae species known as Chlamydomonas reinhardtii. Using techniques the researchers developed for rapidly labeling and evaluating algal proteins, the researchers identified the locations and functions of each protein, detailing the physical interactions between the proteins to create a pyrenoid “interactome.”

The search revealed 89 new pyrenoid proteins, including ones that the researchers think usher carbon into the pyrenoid and others that are required for formation of the pyrenoid. They also identified three previously unknown layers of the pyrenoid that surround the organelle like the layers of an onion. “The information represents the best assessment yet of how this essential carbon-concentrating machinery is organized and suggests new avenues for exploring how it works,” said Luke Mackinder, the study’s first author and a former postdoctoral researcher at the Carnegie Institution who now leads a team of researchers at the University of York, U.K.

In the second study, the researchers report that the pyrenoid, long thought to be a solid structure, is actually liquid-like. Techniques used in previous studies required the researchers to kill and chemically preserve the algae before imaging them. In this new study, the researchers imaged the algae while the organisms were living by using a yellow fluorescent protein to label Rubisco.

Structure of pyrenoid
The researchers conducted a large-scale search for proteins associated with the pyrenoid. The resulting data allowed researchers to propose the most detailed model yet of the spatial organization of the pyrenoid.

While observing the algae, Elizabeth Freeman Rosenzweig, then a Carnegie Institution graduate student, and Mackinder used a high-powered laser to destroy the fluorescent label on Rubisco in half of the pyrenoid, while leaving the label in the other half of the pyrenoid intact. Within minutes, the fluorescence redistributed to the entire pyrenoid, showing that the enzymes easily moved around as they would in a liquid.

Benjamin Engel, a postdoctoral researcher and project leader at the Max Planck Institute of Biochemistry, further explored this finding using another imaging technique called cryo-electron tomography. He froze and prepared whole algae cells and then imaged them with an electron microscope, which is so sensitive that it can resolve the structures of individual molecules.

The technique enabled Engel to visualize the pyrenoid in three dimensions and at nanometer-resolution. By comparing these images with those of liquid systems, the researchers confirmed that the pyrenoid was organized like a liquid. “This is one of the rare examples where classical genetics, cell biology and high-resolution imaging approaches were all brought together in one investigation,” Engel said.

The study enabled the team to ask how a pyrenoid is passed down to the next generation when the single-celled algae divide into two daughter cells. Freeman Rosenzweig noted that the pyrenoid sometimes fails to divide, leaving one of the daughter cells with no pyrenoid.

Using the fluorescent proteins, the team observed that the cell that failed to receive half the pyrenoid in fact could still form one spontaneously. They found that each daughter cell receives some amount of the pyrenoid in its dissolved form and that these nearly undetectable components can condense into a full-fledged pyrenoid.

“We think the pyrenoid dissolution before cell division and condensation after division may be a redundant mechanism to ensure that both daughter cells get pyrenoids,” Jonikas said. “That way, both daughter cells will have this key organelle that’s critical for assimilating carbon.”

Play Video: Cryo-Electron tomography-generated three-dimensional architecture of the pyrenoid

This video demonstrates how cryo-electron tomography can be used to map the three-dimensional architecture of the pyrenoid, imaging its Rubisco enzymes (positions marked by purple spheres) and tubules that deliver materials to the pyrenoid. The video appears in the paper by Elizabeth Freeman Rosenzweig, et al. Cell 2017.

To further explore how this might happen, Jonikas collaborated with Ned Wingreen, Princeton’s Howard A. Prior Professor in the Life Sciences and of Molecular Biology. Wingreen and his team created a computer simulation of the interactions between Rubisco and another protein called EPYC1 — discovered to be crucial to the pyrenoid by Mackinder and others on Jonikas’ team — which acts like glue to stick together multiple Rubiscos.

The computer simulation suggested that the state of the pyrenoid — whether a condensed liquid droplet or dissolved into the surrounding compartment — depended on the number of binding sites on EPYC1. In the simulation, Rubisco has eight binding sites, or eight places where EPYC1 can dock to a Rubisco. If EPYC1 has four binding sites, then two EPYC1s exactly fill all of the docking sites on one Rubisco, and vice versa. Because these fully bonded Rubisco-EPYC1 complexes are small, they form a dissolved state. But if EPYC1 has three or five binding sites, it cannot fill all of the Rubisco sites, and there are open sites on the Rubiscos for binding by additional EPYC1s, which also have free sites that can attract other Rubiscos. The result is a clump of Rubiscos and EPYC1s that form a liquid-like droplet.

The change in the system’s phase depending on the ratio of EPYC1 to Rubisco binding sites can be considered a “magic number” effect, a term typically used in physics to describe conditions where a specific number of particles form an unusually stable state. “These magic numbers, besides being relevant for pyrenoid systems, may have some currency in the field of polymer physics and potentially in synthetic biology,” Wingreen said.

Wingreen and Jonikas are continuing their collaboration and hope to develop the project both theoretically — by exploring different flexibilities and configurations of Rubisco and EPYC1 — and experimentally, by combining the two proteins in a test tube and manipulating the number of binding sites.

“The previous thinking was that the more binding sites they have, the more the proteins tend to cluster,” Jonikas said. “The discovery that there is a magic number effect is important not only for pyrenoids, but perhaps for many other liquid-like organelles found throughout nature.”

With additional studies, these findings may yield important insights into ensuring the availability of fast-growing crops for an expanding world population.

Jonikas, Wingreen, Freeman Rosenzweig, Mackinder, Engel
From left to right: Martin Jonikas, Ned Wingreen, Elizabeth Freeman Rosenzweig, Luke Mackinder and Benjamin Engel.

The first study, “A spatial interactome reveals the protein organization of the algal CO2-concentrating mechanism,” by Luke C.M. Mackinder, Chris Chen, Ryan D. Leib, Weronika Patena, Sean R. Blum, Matthew Rodman, Silvia Ramundo, Christopher M. Adams and Martin C. Jonikas, was published in the journal Cell. 

The work was supported by the National Institutes of Health (grants S10RR027425 and 7DP2GM119137-02), the National Science Foundation (grants EF-1105617 and IOS-1359682), the Simons Foundation and Howard Hughes Medical Institute (grant 55108535), Princeton University, the University of York and the Carnegie Institution for Science.

The second study, “The eukaryotic CO2-concentrating organelle is liquid-like and exhibits dynamic reorganization,” by Elizabeth S. Freeman Rosenzweig, Bin Xu, Luis Kuhn Cuellar, Antonio Martinez-Sanchez, Miroslava Schaffer, Mike Strauss, Heather N. Cartwright, Pierre Ronceray, Jürgen M. Plitzko, Friedrich Förster, Ned S. Wingreen, Benjamin D. Engel, Luke C. M. Mackinder and Martin C. Jonikas, was published in the journal Cell. 

The study was supported by National Science Foundation (grants EF-1105617, IOS-1359682 and PHY-1305525), the Carnegie Institution for Science, the National Institutes of Health (grant T32GM007276), the Simons Foundation and Howard Hughes Medical Institute (grant #55108535), Princeton University, a CONACyT-DAAD Graduate Scholarship, a Fundación Séneca Postdoctoral Fellowship, an Alexander von Humboldt Foundation Postdoctoral Fellowship and Deutsche Forschungsgemeinschaft (grant FO 716/4-1).

New research suggests Mercury’s poles are icier than scientists thought

This NEWS was origynally shared on Sutesuaem Universities News

Fuente: Astrobiology Magazine: Latest News

Colors of Mercury. Image Credit: NASA / JHU Applied Physics Lab / Carnegie Inst. Washington

The scorching hot surface of Mercury seems like an unlikely place to find ice, but research over the past three decades has suggested that water is frozen on the first rock from the sun, hidden away on crater floors that are permanently shadowed from the sun’s blistering rays.  Now, a new study led by Brown University researchers suggests that there could be much more ice on Mercury’s surface than previously thought.

The study, published in Geophysical Research Letters, adds three new members to the list of craters near Mercury’s north pole that appear to harbor large surface ice deposits. But in addition to those large deposits, the research also shows evidence that smaller-scale deposits scattered around Mercury’s north pole, both inside craters and in shadowed terrain between craters. Those deposits may be small, but they could add up to a lot more previously unaccounted-for ice.

“The assumption has been that surface ice on Mercury exists predominantly in large craters, but we show evidence for these smaller-scale deposits as well,” said Ariel Deutsch, the study’s lead author and a Ph.D. candidate at Brown. “Adding these small-scale deposits to the large deposits within craters adds significantly to the surface ice inventory on Mercury.”

The idea that Mercury might have frozen water emerged in the 1990s, when Earth-based radar telescopes detected highly reflective regions inside several craters near Mercury’s poles. The planet’s axis doesn’t have much tilt, so its poles get little direct sunlight, and the floors of some craters get no direct sunlight at all. Without an atmosphere to hold in any heat from surrounding surfaces, temperatures in those eternal shadows have been calculated to be low enough for water ice to be stable. That raised the possibility these “radar-bright” regions could be ice.

That idea got a boost after NASA’s MESSENGER probe entered Mercury’s orbit in 2011. The spacecraft detected neutron signals from the planet’s north pole that were consistent with water ice.

Brown researchers have found new evidence of ice sheets in permanently shadowed craters near the north pole of Mercury. Credit: Head lab / Brown University

For this new study, Deutsch worked with Gregory Neumann from NASA’s Goddard Space Flight Center to take a deep dive into the data returned from MESSENGER. They looked specifically at readings from the spacecraft’s laser altimeter. The device is mostly used to map elevation, but it can also be used to track surface reflectance.

Neumann, an instrument specialist for the MESSENGER mission, helped to calibrate the altimeter’s reflectance signal, which can vary depending upon whether the measurement is taken from directly overhead or at an oblique angle (known as “off-nadir”).  That calibration enabled the researchers to detect high reflectance deposits consistent with surface ice in three large craters for which only off-nadir detections were available.

The addition of those craters to Mercury’s ice inventory is significant. Deutsch estimates the total area of the three sheets to be about 3,400 square kilometers—slightly larger than the state of Rhode Island.

But another major aspect of the work is that the researchers also looked at reflectance data for the terrain surrounding those three large craters. That terrain isn’t as bright as the ice sheets inside the craters, but it’s significantly brighter than the average Mercury surface.

“We suggest that this enhanced reflectance signature is driven by small-scale patches of ice that are spread throughout this terrain,” Deutsch said. “Most of these patches are too small to resolve individually with the altimeter instrument, but collectively they contribute to the overall enhanced reflectance.”

To seek further evidence that such smaller-scale deposits exist, the researchers looked though the altimeter data in search of patches that were smaller than the big crater-based deposits, but still large enough to resolve with the altimeter. They found four, each with diameters of less than about 5 kilometers.

“These four were just the ones we could resolve with the MESSENGER instruments,” Deutsch said. “We think there are probably many, many more of these, ranging in sizes from a kilometer down to a few centimeters.”

Knowing that these small-scale deposits exist, and that they’re likely the source of the slightly brighter surface outside craters, could dramatically increase the ice inventory on Mercury.  Similar small-scale ice deposits are thought to exist on the poles of the Moon. Research models have suggested that accounting for these small-scale deposits roughly doubles the amount of lunar real estate that could harbor ice. The same could be true on Mercury, the researchers say.

How this polar ice may have found its way to Mercury in the first place remains an open question, Deutsch says. The leading hypothesis is that it was delivered by water-rich comet or asteroid impacts. Another idea is that hydrogen may have been implanted in the surface by solar wind, later combining with an oxygen source to form water.

Jim Head, Deutsch’s Ph.D. advisor and co-author of the research, said the work adds a new perspective on a critical question in planetary science.

“One of the major things we want to understand is how water and other volatiles are distributed through the inner solar system—including Earth, the Moon and our planetary neighbors,” Head said. “This study opens our eyes to new places to look for evidence of water, and suggests there’s a whole lot more of it on Mercury than we thought.”

Free citizenship clinics at USC a boon for people in local communities and on USC campuses

This NEWS was origynally shared on Sutesuaem Universities News

Fuente: University of Southern California

http://news.usc.edu/files/2017/09/PaulaHeluBrown_web-480x320.jpg
Attorney and USC alumna Jean Reisz, left, talks with Paula Helu-Brown about her citizenship paperwork. (USC Photo/Gus Ruelas)
USC kicked off its free citizenship clinics this week to help students, staff, faculty and community members complete and file naturalization applications.

A team of attorneys and students with the USC Gould School of Law’s Immigration Clinic is providing free legal support to assist permanent residents who are eligible for naturalized citizenship. More than 200 members of the Trojan Family are taking part in the workshops on the University Park Campus and Health Sciences Campus.

“Thanks to the support of USC, the Immigration Clinic has been able to expand our services to help more people both here on campus and in the neighboring communities,” said Professor Niels Frenzen, the clinic’s director.

Paula Helu-Brown, a postdoctoral fellow at the USC Suzanne Dworak-Peck School of Social Work and a native of Mexico, was excited and relieved when she heard USC was hosting citizenship workshops.

“I tried to handle this process on my own and it is very intimidating,” she said. “It was stressful for me to complete the paperwork while I was working on my dissertation. And it’s expensive to get attorney assistance. I am so thankful to USC for this.”

A firm commitment

As part of the process, USC is also hosting a free 12-week prep course to help with the civics and English tests for USC employees, contract employees and family members of employees or contract employees. In addition, the USC Credit Union is offering micro-loans to members of the USC community for the $725 citizenship application fee. Loans of up to $3,000 are available if multiple applications are being filed for family members.

Check-in table at the clinic

Felix Medina, right, and his wife Alicia check in for the clinic. (USC Photo/Gus Ruelas)

“USC is committed to this initiative. Becoming a citizen is as American as apple pie,” said Martha Escutia, vice president for USC Government Relations. “We want to spread the message to the people who live throughout our communities: Don’t be afraid. The USC Gould Immigration Clinic will help you with the process of becoming a citizen. I hope people take advantage of this opportunity.”

Ana Chavez Maldonado, a junior at USC who immigrated from Guatemala to Los Angeles when she was 2 years old, is pursuing citizenship with her mother. “I am so thankful that USC is taking the initiative in this political climate,” she said.

Aga Paul, a native of Poland and staff member at USC’s International Academy, Global and Strategic Initiatives, has been investigating the citizenship process and was astounded by the high costs of hiring an attorney.

“Receiving this professional assistance for free is like receiving a $3,000 gift from USC.”

Thanks to the clinics at USC, “we will benefit with a stronger community filled with people who feel safe and who will therefore be able to make even more positive contributions to our civic discourse and economy,” Frenzen said.

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Oxford launches digital portal to get school students tackling the 'Big Questions'

This NEWS was origynally shared on Sutesuaem Universities News

Fuente: University of Oxford News

Oxford University has launched an innovative new digital outreach portal aimed at engaging school students aged 11 to 18 with debates and ideas that go beyond what is covered in the classroom.
As the ‘Home of Big Questions’, Oxplore will tackle complex ideas across a wide range of subjects and draw on the latest research carried out at Oxford.

The project aims to raise aspirations, promote broader thinking and stimulate intellectual curiosity. Examples of Big Questions include ‘Is a robot a person?’, ‘Does fake news matter?’, ‘Can war be a good thing?’ and ‘Would you want to live forever?’

Content on Oxplore reflects the kind of thinking students undertake at universities like Oxford and draws on the University’s expertise in everything from archaeology to zoology, offering approaches to challenges and questions underpinned by the latest thinking and research.

Dr Samina Khan, Director of Undergraduate Admissions and Outreach at Oxford University, said: ‘Oxplore can underpin outreach work from right across the collegiate University. It complements and adds value to our current programmes, but the digital medium also gives us the opportunity to have sustained contact with young people who are geographically distant from Oxford.

‘The engaging design and content and the independent study it encourages may also reach those who for whatever reason don’t think Oxford is for them. From an early age we can start to dispel this belief and at the same time nurture intellectual curiosity. Developing this new platform has allowed us to challenge ourselves, innovate and create something entirely new.

‘Supporting access and outreach work at Oxford is essential to helping us ensure Oxford is accessible to all and we can select the best students purely on academic merit and passion for their subject.’

Oxplore has been built and created by the University of Oxford for young people as part of its commitment to reaching the best students from every kind of background. The project is co-ordinated by the University’s Widening Access and Participation team, which delivers outreach work with young people across the UK.