August 2019

Simple Method Yields Complex Micro and Nanoparticle Shapes

first_img New imaging method aids in water decontamination “There is a shortage of methods to produce non-spherically shaped polymer particles. We have developed a method that addresses this challenge,” said UCSB engineer Samir Mitragotri, the study’s corresponding scientist, to method is fairly simple, low cost, and can produce substantial quantities of particles (from billions to trillions) of more than 20 widely varying shapes. These include rods, various disks, bullets, barrels, and lenses.The particles are made of polystyrene, a polymer most commonly used to make foam packaging materials. The pre-shaped particles are spherical and have diameters between 60 nanometers (billionths of a meter) and 10 micrometers (millionths of a meter).The particles are first suspended in a polymer solution, cast into films of varying thicknesses, and mixed with the compound glycerol to plasticize the films. The films were then dried. From there, the researchers used two approaches, dubbed A and B, and then a combination of the two, to engineer the full array of shapes.In approach A, the particles were melted using either a solvent or heat and then the entire film was stretched on an apparatus custom built for the task. By stretching the film in one, two, or both directions, the particles were pulled into various shapes. Different shapes resulted from the use of solvent versus heat, and the thickness of the film also produced new geometries. Among the shapes yielded by approach A were circular disks, rectangular disks, “flying saucers,” rods, and worms.In approach B, the films were stretched before melting, which produced a different set of shapes than A, most more complex, including pulley wheels, barrels, bullets, and capsules.Combining approaches A and B resulted in yet another set of shapes, many rather unusual. These included ribbon-like particles with curled ends, elongated hexagonal disks, and even “ravioli” and “tacos.”Most of the shapes produced were a few micrometers in size, but the scientists were able to produce nanoparticles, which greatly increases the particles’ potential applications. The group says that particles made of polymers other than polystyrene could be produced using their method, and that the method is scalable to produce even greater numbers of them.Added Mitragotri, “There is already evidence supporting the importance of particle shape in various applications, such as the design of new carriers for drug delivery. We believe that the availability of a simple method to make these particles will lead to many new discoveries and technologies.”Citation: Julie A. Champion, Yogesh K. Katare, and Samir Mitragotri (2007) Proc Natl Acad Sci USA 104:11901-11904Copyright 2007 All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of In applications from drug delivery to electronics, polymer particles several billionths to millionths of a meter in size could play key roles. But before many of these uses can be realized, scientists must thoroughly understand how these particles behave – behaviors that are strongly linked to the particles’ precise shapes, which so far have been difficult to produce on demand and in variation. Recently, however, scientists from the University of California at Santa Barbara (UCSB) found a way to widen this bottleneck. Citation: Simple Method Yields Complex Micro- and Nanoparticle Shapes (2007, July 26) retrieved 18 August 2019 from A collection of scanning electron microscope images (color added) of the particle shapes, including capsules (C), “tacos” (E), and lenses (R). Photo courtesy of Samir Mitragotri. Explore further This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

Toshiba bites Apple with 498 ppi display

first_img Toshiba LCD Panel Zooms In-and-Out By Bending It (w/ Video) Citation: Toshiba bites Apple with 498 ppi display (2011, October 24) retrieved 18 August 2019 from “Astounding,” “staggering,” and “Prepare to have your eyes melted,” were some of the reactions. Reports hastened to compare display numbers with those from Apple. Suddenly Apple’s “retina display” iPhone 4/4S smartphones of 326 ppi was a less exciting feat. Adjectives like “razor sharp” were usurped from Apple’s gate and replanted at Toshiba’s.Among other bragging points is the fact that Toshiba’s display can show 16.7 million different colors. Toshiba describes the display technology as based on processing techniques with low-temperature poly-silicon (LTPS) thin-film transistors (TFT) on glass substrates and other fabrication techniques that Toshiba has cultivated over the years.Toshiba credits its LTPS technology as the enabler of advancements like the new LCD display. Low temperature poly silicon makes possible higher pixel density, which in turn makes text and images more readable. That’s especially useful in smaller device screens like handhelds and portable diagnostic equipment, as well as for larger screens, says Toshiba. Explore further More information: Press release © 2011 The display is for 2-D images but the LCD panel achieves “high-definition images with photographic quality,” says Toshiba, and those images impart depth and realism.Missing from the announcement were specifics on how the display will translate into product. Many are wondering what type of end product will use the display.One easy assumption is that the display will translate into smaller tablets but a few observers are raising questions about that. The hardware review site AnandTech asks, what is the use for a 6.1-inch display? The report points out that smaller 4.5-inch displays are, with a few exceptions, the maximum for most smartphones. As for tablets, they usually start at 7 inches. Toshiba’s display at 6.1 inches hovers over both categories, too big for smartphones and too small for tablets.Others guess that Toshiba’s targets may be e-reader manufacturers who want to take their displays to a newer level. Those in Yokohama, Japan, this week will be able to see the LCD panel at the FPD International 2011 from October 26 to 28. Enhanced viewing and graphics capabilities are a competitive feature in mobile devices, as manufacturers strive to respond to user wants, needs, and expectations.Toshiba’s new-to-showcase LCD, with its superior resolution, has already attracted much attention. For now, though, in the absence of any product details from Toshiba, Apple can still rest on its laurels. As Apple tells the world, its “retina display” makes viewing “hundreds of pixels better.” ( — As soon as Toshiba announced its 6.1-inch Liquid crystal display (LCD) panel last week, bloggers and tech news sites were noting the numbers and poking at mobile display monarchs Apple. Toshiba’s new display packs a 2560×1600 resolution with a 1000:1 contrast ratio. The display works out to 498 pixels per inch (ppi). This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

New extended ionized gas clouds detected in Abell 1367 cluster

first_img Citation: New extended ionized gas clouds detected in Abell 1367 cluster (2017, April 5) retrieved 18 August 2019 from Dozens of new ultra-diffuse galaxies discovered in Abell 2744 Explore further Abell 1367 cluster. The background image is R-band of Palomar Digitized Sky Survey 2 (DSS2). The size of the image is 75 arcmin square. The solid boxes represent the observed regions in this study. Credit: Yagi et al., 2017. More information: Extended ionized gas clouds in the Abell 1367 cluster, arXiv:1703.10301 [astro-ph.GA] surveyed a central 0.6 deg^2 region of Abell 1367 cluster for extended ionized gas clouds (EIGs) using the Subaru prime-focus camera (Suprime-Cam) with a narrow-band filter that covers Halpha. We discovered six new EIGs in addition to five known EIGs. We also found that the Halpha tail from the blue infalling group (BIG) is extended to about 330 kpc in projected distance, which is about twice longer than previously reported. Candidates of star-forming blobs in the tail are detected. The properties of the EIG parent galaxies in Abell 1367 basically resemble those in the Coma cluster. A noticeable difference is that the number of detached EIGs is significantly fewer in Abell 1367, while the fraction of blue member galaxies is higher. The results suggest a difference in the evolutionary stage of the clusters; Abell 1367 is at an earlier stage than the Coma cluster. (—Astronomers have found six new extended ionized gas clouds (EIGs) in the galaxy cluster Abell 1367 (also known as the Leo Cluster). The discovery expands the current list of the cluster’s known EIGs to 11 and provides new clues about the evolution of this group of galaxies. The researchers detailed their findings in a paper published Mar. 30 on © 2017 Located some 330 million light years away in the constellation Leo, Abell 1367 is a young cluster containing at least 70 major galaxies. The cluster is best known for its high fraction of spiral galaxies, low central galaxy density and the irregular shape of hot gas distribution. Moreover, Abell 1367 is one of the best-studied nearby clusters in H-alpha (Hα) spectral line. To date, numerous Hα observations of this cluster have been conducted with the aim of detecting the presence of ionized gas.Such studies are of high importance for astronomers due to the fact that gas around a galaxy in a cluster is an indicator of a recent or ongoing gas-loss event of the parent galaxy. Therefore, finding new EIGs is crucial for detecting gas loss from star-forming galaxies, which could result in better understanding of galaxy evolution processes.The new research paper authored by Masafumi Yagi of the National Astronomical Observatory of Japan (NAOJ) and his team reveals the presence of new EIGs in Abell 1367 and provides more details on the nature of this cluster. In this paper, the researchers described their observations of the central region of Abell 1367 using the Subaru Telescope in Hawaii.”We surveyed a central 0.6 deg2 region of Abell 1367 cluster for extended ionized gas clouds using the Subaru prime-focus camera (Suprime-Cam) with a narrow-band filter that covers Hα,” the paper reads.The observational campaign was carried out in April and May 2014 and resulted in the discovery of six new EIGs in Abell 1367 in addition to five such clouds known before. Furthermore, the data provided by the Subaru Telescope allowed the researchers to find that the Hα tail from the blue infalling group (BIG) is extended to about 1.08 million light years in projected distance, which is about two times longer than previously thought.”The deep Hα image also revealed that the Hα tails are extended in fainter surface brightness much longer than previously known,” the scientists wrote.Given the fact that Abell 1367 together with Abell 1656 (Coma Cluster) make up the SCl 117 supercluster (also known as the Coma Supercluster), the team compared this two clusters taking the new results into account. In general, they found that the properties of the EIG parent galaxies in Abell 1367 basically resemble those in Abell 1656.”The comparison of the parent galaxies of EIGs in Abell 1367 and in the Coma Cluster showed that the properties of the parents are basically similar,” the researchers wrote in the paper.However, one meaningful difference was found by Yagi’s team. They revealed that the length of EIGs is longer and more often connected to star-forming parents in Abell 1367. This indicates that the EIGs and parents in Abell 1367 are, on average, younger than those in Abell 1656. It also means that gas removal from the parent and heating of EIG is slower in Abell 1367. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

Astronomers detect dozens of new quasars and galaxies

first_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Explore further High-redshift quasars and galaxies (at redshift higher than 5.0) are useful probes of the early universe in many respects. They offer essential clues on the evolution of the intergalactic medium, quasar evolution, early supermassive black hole growth, as well as evolution of galaxies through cosmic times. Generally speaking, they enable scientists to study the universe when it looked much different than it does today.Recently, Matsuoka’s team has presented the results from the Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs) project, which uses multi-band photometry data provided by the Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP) survey. HSC is a wide-field camera installed on the Subaru 8.2 m telescope located at the summit of Maunakea, Hawaii and operated by NAOJ. The researchers selected nearly 50 photometric candidates from the HSC-SSP source catalog and then observed them with spectrographs on the Subaru Telescope and the Gran Telescopio Canarias (GTC), located on the island on the Canary Island of La Palma, Spain.The observations resulted in the identification of 24 new quasars and eight new luminous galaxies at redshift between 5.7 and 6.8.”We took optical spectra of 48 candidates with GTC/OSIRIS and Subaru/FOCAS, and newly discovered 24 quasars and 8 luminous galaxies at 5.7 < z ≤ 6.8," the paper reads.According to the study, the newly detected quasars have lower luminosity than most of the previously known high-redshift quasi-stellar objects, in contrast to the new galaxies, which have extremely high luminosity when compared to other galaxies found at similar redshift. The quasar with the highest redshift (6.8) described in the paper received designation J1429 − 0104, while the one with the lowest redshift (5.92) was named J0903 + 0211. Among the new galaxies, J1628 + 4312 was found at the highest redshift (6.03) and J2237 − 0006 at the lowest (5.77). J2237 − 0006 is also the most luminous newly found galaxy.Meanwhile, the researchers revealed that the SHELLQs project continues, and more new quasars are being discovered, which will be reported in forthcoming papers. "Further survey observations and follow-up studies of the identified objects, including the construction of the quasar luminosity function at z ∼ 6, are ongoing," they wrote in the paper.The authors also noted that they plan to conduct follow-up observations of the newly discovered quasars and galaxies at various wavelengths from sub-millimeter/radio to X-ray. Several of these objects have already been observed with the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, near-infrared spectrographs on the Gemini telescope, located in Hawaii and the Very Large Telescope (VLT), also in Chile. © 2017 Citation: Astronomers detect dozens of new quasars and galaxies (2017, April 25) retrieved 18 August 2019 from More information: Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). II. Discovery of 32 Quasars and Luminous Galaxies at 5.7 < z < 6.8, arXiv:1704.05854 [astro-ph.GA] present spectroscopic identification of 32 new quasars and luminous galaxies discovered at 5.7 < z < 6.8. This is the second in a series of papers presenting the results of the Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs) project, which exploits the deep multi-band imaging data produced by the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey. The photometric candidates were selected by a Bayesian probabilistic algorithm, and then observed with spectrographs on the Gran Telescopio Canarias and the Subaru Telescope. Combined with the sample presented in the previous paper, we have now identified 64 HSC sources over about 430 deg2, which include 33 high-z quasars, 14 high-z luminous galaxies, 2 [O III] emitters at z ~ 0.8, and 15 Galactic brown dwarfs. The new quasars have considerably lower luminosity (M1450 ~ -25 to -22 mag) than most of the previously known high-z quasars. Several of these quasars have luminous (> 10^(43) erg/s) and narrow (< 500 km/s) Ly alpha lines, and also a possible mini broad absorption line system of N V 1240 in the composite spectrum, which clearly separate them from typical quasars. On the other hand, the high-z galaxies have extremely high luminosity (M1450 ~ -24 to -22 mag) compared to other galaxies found at similar redshift. With the discovery of these new classes of objects, we are opening up new parameter spaces in the high-z Universe. Further survey observations and follow-up studies of the identified objects, including the construction of the quasar luminosity function at z ~ 6, are ongoing. Reduced spectra of the first set of eight quasars and possible quasars discovered in this work, displayed in decreasing order of redshift. The object name and the estimated redshift are indicated at the top left corner of each panel. The blue dotted lines mark the expected positions of the Lyα and N V λ1240 emission lines, given the redshifts. The spectra were smoothed using inverse-variance weighted means over 3 – 9 pixels (depending on the S/N), for display purposes. The bottom panel displays a sky spectrum, as a guide to the expected noise. Credit: Matsuoka et al., 2017. (—A team of astronomers led by Yoshiki Matsuoka of the National Astronomical Observatory of Japan (NAOJ) has detected a treasure trove of new high-redshift quasars (or quasi-stellar objects) and luminous galaxies. The newly found objects could be very important for our understanding of the early universe. The findings were presented Apr. 19 in a paper published on High-redshift quasar discovered by Pan-STARRSlast_img read more

Delhi pujas go the theme way

Innovation in times of financial crisis — this is a theme that seems common to the Durga Puja preparations across the Capital.As the puja committees blame the economic constraints, they are also making the most of it with innovative themes such as ecology, rural life, Bengali icons and cuisine.At the Kashmere Gate Durga Puja, one of Delhi’s oldest pujas where the festivities will enter the 103rd year, the colour green and Bengali tradition are touchstones for the rites of invocation. Also Read – ‘Playing Jojo was emotionally exhausting’‘Every year, we allow non-profit groups to collect flowers used in the rituals to extract eco-friendly colours. This year too, many groups are keen to harvest used flowers,’ said Samarendra Bose.Even the idol is eco-friendly, with the ek chala [single frame] idol sculpted in chalk to help it easily dissolve in water during immersion. The idol has been made by Biswajit Pal, an artisan from Calcutta. The pandal or marquee has a rustic flavour reminiscent of the idyllic life of Bengal’s lush countryside. The spotlight, however, is on food. ‘The Also Read – Leslie doing new comedy special with Netflixbhog is important. We feed at least 3,000 people every year,’ he said.Like Kashmere Gate, the emerging theme of this year’s Durga Puja in different parts of the Capital appears to be food.On Sunday, there was a four-hour Delhi Food Walk tour that took food lovers through Chittaranjan Park to taste kathi rolls, phuchka, jhaal-moori, mutton ghugni and fish cutlets and catch a glimpse of the dhunuchi naach, the arti (invocation) dance before the idols to the beat of the dhaks. At the K-Block puja, the scaling down of ostentation will be compensated by nine items on the bhog menu. The theme of the B-Block puja is the 150th birth anniversary of seer-philosopher Swami Vivekananda. The marquee resembles the Vivekananda Rock Memorial in Kanyakumari and the interiors echo the Belur Math. There are also portraits of Vivekananda and extracts from his address at a convention of religions in Chicago in 1897.The Navapalli Puja Samiti in Pocket 40 depicts how the households of landlords in rural Bengal celebrate the festival in thakur dalan — the pillared courtyard outlying private shrines.The Puja committee in Durgotsav, Greater Kailash-II has adopted the girl child as its theme all over the pandal. Maha Kumari — the figure of a schoolgirl standing over on a lion and carrying a trident and a disc — is at the entrance of pandal that has a village mud hut facade and have walls on which children will be allowed to paint. The high point is serving of bhog, served by the women of the puja committee. [IANS] read more

Holy Cow Its art

first_imgLove is not love which alters when it alteration finds. So spake the Bard. And now, centuries later, Singapore-based artist P. Gnana has given artistic touches to his expression of love in his latest exhibition Nothing Else but Love. Gnana dwells on the emotion with the help of humans and an animal — the cow! Using recycled media, oils, fabrics and mixed media — the artist has created paintings, sculptures in bronze and even installations. Shakespeare’s immortal line — Also Read – ‘Playing Jojo was emotionally exhausting’Things base and vile, holding no quantity, love can transpose, to form and dignity — from A Midsummer Night’s Dream, set the tone of the exhibition. ‘The gestures which you can’t do in real life are what I try to portray in my works,’ says Gnana. ‘They express the yearning for an eternal companion,’ he adds. His recent works, though varied, speak the same language — that of love. The Umbilical Bond (oil on canvas), dwells on a mother’s love for her child. The same emotion is portrayed in Also Read – Leslie doing new comedy special with NetflixTimeless Intoxication (oil on canvas) and Reason to live (oil and fabric collage on canvas).     The works are marked by bold strokes and a riot of colours. Androgyny is noticed in some figures but mostly the figures are stark and well shaped. Cows form a major part of his works. Gnana, known widely as a ‘cow-painting artist’ attributes this to his love for the animal. Growing up in Naiveli in Tamil Nadu, the artist grew up seeing cows in the roadside.    ‘My works are part imagination and part memories of the past. Whatever I see, I pepper it with my imagination and use it in my works at some point of time,’ explains the artist.  Incarnation I stands out among his works. It is an installation made out of recycled media that includes parts of two-wheelers and four wheelers which have been added to welded materials. Go take a look and see for yourself the various expressions of love.DETAILAt: Art Spice, The Metropolitan Hotel & Spa, Near Bangla SahibOn till: 30 November Timings:  10 am to 7 pmlast_img read more

4th Annual Indian Comics Convention all set for a Grand show

first_imgMark Waid, an Eisner Award-winning American comic book writer, known for his work on Marvel Comics’ Captain America and David Lloyd, a British comics artist best known as the illustrator of the story V for Vendetta  along with other renowned International personalities are going to be a part of this years gala.Some of the best International comics publishers are coming this year especially for Indian Comic Con. The main participants for the 4th Annual Indian Comic Con are Amar Chitra Katha, Orange Radius, Abhijeet Kini, Pop Culture Publishing, Random House, Campfire Graphic Novel, Holy Cow Entertainment, HarperCollins Publishers,Vimanika Comics, iComics, Manta Ray Comics, DC, Vertigo & Kodansha Comics By Random House India, Viz Media by Simon & Schuster India, Blaft Publications, Chariot Comics, Scholastic India, Meta Desi Comics and more!!  Various workshops will be conducted by creators, artistes and writers of popular comics and graphic novels. Over five new book titles to be launched during the event. The three-day convention will hold sessions With Leading Artists, writers and publishers from India and abroad.  Jatin Varma, founder, Comic Con India, said ‘We are kickstarting our 4th year in a big way by revamping our entire event, adding more exhibitors and content. There will be a lot more for the visitors to do at the event. We aim to take the fan experience up a notch and bring it closer to International standards. With the introduction of nominal ticketing, we hope to provide a lot many more amenities to visitors and our participants.’From this convention onwards, the Comic Con India Awards are going to take place during the main convention itself. CCI aims to recognise the work of all the professionals of India’s Comics Industry.When: 7-9 FebruaryWhere: Thyagraj Stadium (INA)last_img read more