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New Sci-Tech Achievements

Sunday, December 5, 2010

Compiled By: Firouzeh Mirrazavi
Deputy Editor of Iran Review

Active Image*TUMS Researchers Produce Drug for Diabetic Ulcer

Researchers at the Tehran University of Medical Sciences (TUMS) have produced a drug for treating and preventing diabetic neuropathy, microangiopathy and diabetic and non-diabetic ulcers and wound injection.

Mihan Jafari Javid, who led the research, said the drug treats ulcers within two weeks.

She filed for a patent for the drug and received a US patent this year.
 
Pathophysiology sometimes occurs when a person has had diabetes mellitus for a long time. High blood glucose levels cause the endothelial cells lining the blood vessels to take in more glucose than normal (these cells do not depend on insulin).

They then form more glycoproteins on their surface than normal, and also cause the basement membrane to grow thicker and weaker. The walls of the vessels become abnormally thick but weak, and therefore bleed, leak protein, and slow the flow of blood through the body.

Some cells, for example in the retina (diabetic retinopathy) or kidney (diabetic nephropathy), may not get enough blood and may be damaged. Nerves, if not sufficiently supplied with blood, are also damaged which may lead to loss of function (diabetic neuropathy).

Massive microangiopathy may cause microangiopathic hemolytic anemia (MAHA).

Diabetic neuropathies are neuropathic disorders that are associated with diabetes mellitus. These conditions are thought to result from diabetic microvascular injury involving small blood vessels that supply nerves (vasa nervorum) in addition to macrovascular conditions that can culminate in diabetic neuropathy.

Relatively common conditions which may be associated with diabetic neuropathy include third nerve palsy; mononeuropathy; mononeuropathy multiplex; diabetic amyotrophy; a painful polyneuropathy; autonomic neuropathy; and thoracoabdominal neuropathy.

Active Image*Inulin Produced By Ultrasound Waves

Iranian researchers have produced a variation of anti-cancer, inulin powder through extraction of inulin from local plants by means of ultrasound waves.

Elnaz Milani, lead researcher in the Department of Food Science and Technology, Ferdowsi University of Mashhad (FUM), said that in the EU and the US, industrial inulin is exclusively extracted from Cichorium Intybus.

“However, Iranian researchers decided to select another plant for the extraction of inulin after they found that the Iranian version of Cichorium Intybus carried poor stocks of the raw material due to weather conditions,” he said.

“We found that topinambur (Helianthus tuberosus), tragopogon (goatsbeard) and artichoke, which are abundantly available in the west and northwest of Iran, are far richer in inulin stocks.”

The researchers also found that ultrasound waves are far more effective in facilitating the extraction of inulin and its conversion into powder than water which is used in the conventional method.

Inulins are a group of naturally occurring polysaccharides produced by many types of plants. They belong to a class of fibers known as fructans. It is used by some plants as a means of storing energy and is typically found in roots or rhizomes. Most plants that synthesize and store inulin do not store other materials such as starch.

Inulin stimulates the growth of beneficial bacteria in the colon, including bifidobacteria and lactobacilli, thereby modulating the composition of microflora.

This creates an environment that protects against pathogens, toxins and carcinogens, which can cause inflammation and cancer.

In addition, fermentation of inulin leads to an increase in short-chain fatty acids and lactic acid production, thereby reducing colonic pH, which may further control pathogenic bacteria growth and may contribute to inulin’s cancer protective properties.

Active Image*Iranian Wins Stockholm Univ. Award

Iranian researcher Mohammad Reza Shariat-Gorji from Stockholm University won the award for the best PhD thesis in biomedical and pharmaceutical analysis in Sweden in 2010.

The 25,000-Kronor award has been awarded since 2004 by the Swedish Academy of Medical Sciences to the best university student research in the form of a thesis.

This is the second time an Iranian researcher has won the Swedish award.
 
Shariat-Gorji carried out research entitled Novel Cleanup, Concentration and Laser Desorption/Ionization Strategies for Mass Spectrometry.

The ceremony was held at Belfrage Hall BMC, Lund University, on Nov. 2, 2010.

*Iranian Named Recipient of Morris Cohen Award

Pouria Ghods has been named the recipient of the Electrochemical Society Corrosion Division’s 2010 Morris Cohen Graduate Student Award.

Active ImageAccording to Carleton.ca, he received his BSc degree in 2001 and his MSc degree in 2004, both in civil engineering from University of Tehran, Iran. He joined the PhD program at Carleton University and conducted research on corrosion of infrastructure with O. Burkan Isgor as his advisor.

He completed part of his experimental work at CANMET Materials Technology Laboratories (MTL) in Canada. He obtained his doctorate in civil engineering materials in June 2010. The main goal of Ghods’ PhD study was to carry out multi-scale investigations of the formation and chloride-induced breakdown of passive films on steel in the highly alkaline environment of concrete.

The multi-scale investigation was designed to bridge length scales from the nanoscale to the macroscopic. In addition to traditional electrochemical methods such as electrochemical impedance spectroscopy (EIS), he used highly specialized experimental techniques, such as transmission electron microscopy (TEM) of the samples, based on ion beam (FIB) technique and X-ray photoelectron spectroscopy (XPS) as well as atomic force microscopy (AFM) to characterize the passive film properties both in the absence and presence of chloride.

Ghods has 40 peer-review publications, including 13 journal articles, to his credit. He has received several awards, including the NACE Foundation Academic Award in 2009, an NSERC Postdoctoral Fellowship in 2010 and the Jagmohan Humar Graduate Student Fellowship in 2007.

His research interests are numerical modeling of steel corrosion in concrete, microscopic studies of passivity and pitting corrosion, non-destructive corrosion measurement of rebars in concrete structures and evaluation of coatings performance in aggressive environments.

Active Image*Iran produces biodegradable materials

Iranian researchers have managed to produce biodegradable raw materials, using a very simple method and without any need for special equipment.

"One of the problems facing societies today is the issue of environmental pollution because of plastic materials, especially materials used in the packaging industry such as plastic bags and disposable dishes," said Saeid Zoka'i, the managing director of the company which has produced biodegradable compounds in the country.

Numerous studies are being conducted across the world to produce materials which can degrade and be absorbed by nature, he said.

"In Iran, too, efforts have been made in that regard," he added. "However, the (raw) materials produced and used in disposable dishes often need special machinery, which requires most packaging industries in the country to replace their systems completely."

"To that end, we focused our research on biodegradable compounds (raw materials) which can be produced with the existing packaging equipment, and at the end, we managed to produce biodegradable compounds," he went on to say.

According to Zoka'I, the compounds (raw materials) can be used in producing different kinds of disposable dishes, plastic bags and packaging items.

"The best advantage of these compounds is that they are absorbed by nature," he underlined.

Biodegradable materials are also flexible and strong, he concluded.

Active Image*Cobalt Phosphate Pigments Synthesized

Iranian researchers at Amir Kabir University of Technology synthesized flowerlike cobalt phosphate nanostructures for use in the dye industry.

Cobalt phosphate is a violet ceramic pigment which, when reduced to nanometer, will have improved durability, efficiency, uniformity and color luster.

“We synthesized flowerlike and plate-like nanopigments of cobalt phosphate with appropriate particle sizes and no surfactant or similar additive in Amir Kabir University of Technology,” Mohammad Badsar, MS in chemical engineering, said.

Stressing the use of reverse micelle route for the synthesis, he said, “This nanomaterial finds applications in dye industry, rechargeable lithium batteries (as cathode) and catalysts used in solar energy conversion. Currently, only microstructured cobalt phosphate is used in the dye industry.”

The details of this study are published in Materials Research Bulletin, volume 45, pages 1080-84, 2010.

Active Image*Neuroscientists find that the same face may look male or female, depending on where it appears in a person’s field of view.

Neuroscientists at MIT and Harvard have made the surprising discovery that the brain sees some faces as male when they appear in one area of a person’s field of view, but female when they appear in a different location.

The findings challenge a longstanding tenet of neuroscience — that how the brain sees an object should not depend on where the object is located relative to the observer, says Arash Afraz, a postdoctoral associate at MIT’s McGovern Institute for Brain Research and lead author of a new paper on the work.

“It’s the kind of thing you would not predict — that you would look at two identical faces and think they look different,” says Afraz. He and two colleagues from Harvard, Patrick Cavanagh and Maryam Vaziri Pashkam, described their findings in the Nov. 24 online edition of the journal Current Biology.

In the real world, the brain’s inconsistency in assigning gender to faces isn’t noticeable, because there are so many other clues: hair and clothing, for example. But when people view computer-generated faces, stripped of all other gender-identifying features, a pattern of biases, based on location of the face, emerges.

The researchers showed subjects a random series of faces, ranging along a spectrum of very male to very female, and asked them to classify the faces by gender. For the more androgynous faces, subjects rated the same faces as male or female, depending on where they appeared.

Study participants were told to fix their gaze at the center of the screen, as faces were flashed elsewhere on the screen for 50 milliseconds each. Assuming that the subjects sat about 22 inches from the monitor, the faces appeared to be about three-quarters of an inch tall.

The patterns of male and female biases were different for different people. That is, some people judged androgynous faces as female every time they appeared in the upper right corner, while others judged faces in that same location as male. Subjects also showed biases when judging the age of faces, but the pattern for age bias was independent from the pattern for gender bias in each individual.

Afraz believes this inconsistency in identifying genders is due to a sampling bias, which can also be seen in statistical tools such as polls. For example, if you surveyed 1,000 Bostonians, asking if they were Democrats or Republicans, you would probably get a fairly accurate representation of these percentages in the city as a whole, because the sample size is so large. However, if you took a much smaller sample, perhaps five people who live across the street from you, you might get 100 percent Democrats, or 100 percent Republicans. “You wouldn’t have any consistency, because your sample is too small,” says Afraz.

He believes the same thing happens in the brain. In the visual cortex, where images are processed, cells are grouped by which part of the visual scene they analyze. Within each of those groups, there is probably a relatively small number of neurons devoted to interpreting gender of faces. The smaller the image, the fewer cells are activated, so cells that respond to female faces may dominate. In a different part of the visual cortex, cells that respond to male faces may dominate.

“It’s all a matter of undersampling,” says Afraz.

Michael Tarr, codirector of the Center for the Neural Basis of Cognition at Carnegie Mellon University, says the findings add to the growing evidence that the brain is not always consistent in how it perceives objects under different circumstances. He adds that the study leaves unanswered the question of why each person develops different bias patterns. “Is it just noise within the system, or is some other kind of learning occurring that they haven’t figured out yet?” asks Tarr, who was not involved in the research. “That’s really the fascinating question.”

Afraz and his colleagues looked for correlations between each subject’s bias pattern and other traits such as gender, height and handedness, but found no connections.

He is now doing follow-up studies in the lab of James DiCarlo, associate professor of neuroscience at MIT, including an investigation of whether brain cells can be recalibrated to respond to faces differently.

Active Image*Novel Method for Measuring Hydrazine

Iranian researchers at the University of Tabriz succeeded in measuring hydrazine at a cheaper price with the help of electrodes modified by silver nanoparticles.

Recent reports on severe hydrazine poisoning indicate that swallowing about 20-50 ml of hydrazine can prove to be fatal.

It has been proved that hydrazine causes cancer in laboratory animals. However, there is insufficient evidence to prove such claim about humans. Therefore, the measurement of hydrazine is an important issue considered by Tabrizi researchers.

“Electrochemical methods are the cheapest, simplest and the most exact in measuring hydrazine,” Mirqassem Hosseini, a lecturer at University of Tabriz, said.

“The main problem in measuring hydrazine with solid electrodes is its relatively high tendency for oxidation. Metals such as gold, platinum and silver are suitable for anodic oxidation of hydrazine, but they are not cost-effective in industry,” he added.
 
Mirqassem believes the solution to this problem is the use of “modifiers for the electrode surface”.

“To this end, titanium has been used as the sub-layer in this research.”

Noting that titanium is an active metal that oxidizes quickly at room temperature and a non-homogeneous, sticky layer of titanium oxide is formed on its surface, he said, “Therefore, the first stage is to remove that sub-layer, which is possible through various methods.”

“After the removal of the sub-layer from the surface of titanium, we formed a coating of polyaniline through an electro-polymerization process. Then we formed a coating of silver nanoparticles on the surface of that polymeric coating. In the end, we analyzed its electrocatalytic activity in the electrochemical oxidation reaction of hydrazine,” he said.

Hydrazine is mainly used as a foaming agent in preparing polymer foams, but significant applications also include its uses as a precursor to polymerization catalysts and pharmaceuticals. Additionally, hydrazine is used in various rocket fuels and for preparing the gas precursors used in airbags.

Active ImageA new twist for nanopillar light collectors

Sunlight represents the cleanest, greenest and far and away most abundant of all energy sources, and yet its potential remains woefully under-utilized. High costs have been a major deterrant to the large-scale applications of silicon-based solar cells. Nanopillars – densely packed nanoscale arrays of optically active semiconductors – have shown potential for providing a next generation of relatively cheap and scalable solar cells, but have been hampered by efficiency issues. The nanopillar story, however, has taken a new twist and the future for these materials now looks brighter than ever.

"By tuning the shape and geometry of highly ordered nanopillar arrays of germanium or cadmium sulfide, we have been able to drastically enhance the optical absorption properties of our nanopillars," says Ali Javey, a chemist who holds joint appointments with the Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) at Berkeley.

Javey, a faculty scientist with Berkeley Lab's Materials Sciences Division and a UC Berkeley professor of electrical engineering and computer science, has been at the forefront of nanopillar research. He and his group were the first to demonstrate a technique by which cadmium sulfide nanopillars can be mass-produced in large-scale flexible modules. In this latest work ("Ordered Arrays of Dual-Diameter Nanopillars for Maximized Optical Absorption"), they were able to produce nanopillars that absorb light as well or even better than commercial thin-film solar cells, using far less semiconductor material and without the need for anti-reflective coating.

“To enhance the broad-band optical absorption efficiency of our nanopillars we used a novel dual-diameter structure that features a small (60 nanometers) diameter tip with minimal reflectance to allow more light in, and a large (130 nanometers) diameter base for maximal absorbtion to enable more light to be converted into electricity," Javey says. "This dual-diameter structure absorbed 99-percent of incident visible light, compared to the 85 percent absorbtion by our earlier nanopillars, which had the same diameter along their entire length."

Theoretical and experimental works have shown that 3-D arrays of semiconductor nanopillars – with well-defined diameter, length and pitch – excel at trapping light while using less than half the semiconductor material required for thin-film solar cells made of compound semiconductors, such as cadmium telluride, and about one-percent of the material used in solar cells made from bulk silicon. But until the work of Javey and his research group, fabricating such nanopillars was a complex and cumbersome procedure.

Javey and his colleagues fashioned their dual diameter nanopillars from molds they made in 2.5 millimeter-thick alumina foil. A two-step anodization process was used to create an array of one micrometer deep pores in the mold with dual diameters – narrow at the top and broad at the bottom. Gold particles were then deposited into the pores to catalyze the growth of the semiconductor nanopillars.

"This process enables fine control over geometry and shape of the single-crystalline nanopillar arrays, without the use of complex epitaxial and/or lithographic processes," Javey says. "At a height of only two microns, our nanopillar arrays were able to absorb 99-percent of all photons ranging in wavelengths between 300 to 900 nanometers, without having to rely on any anti-reflective coatings."
The germanium nanopillars can be tuned to absorb infrared photons for highly sensitive detectors, and the cadmium sulfide/telluride nanopillars are ideal for solar cells. The fabrication technique is so highly generic, Javey says, it could be used with numerous other semiconductor materials as well for specific applications. Recently, he and his group demonstrated that the cross-sectional portion of the nanopillar arrays can also be tuned to assume specific shapes – square, rectangle or circle – simply by changing the shape of the template.

"This presents yet another degree of control in the optical absorption properties of nanopillars," Javey says.

Javey's dual-diameter nanopillar research was partially funded through the National Science Foundation's Center of Integrated Nanomechanical Systems (COINS) and through Berkeley Lab LDRD funds.

Active Image*Trans-genetic mouse produced in Iran

Iranian researchers have succeeded in producing the first trans-genetic mouse in the western province of Kurdistan.

The research project was conducted in the Kurdistan University of Medical Sciences.

The Head of Kurdistan University of Medical Sciences said that even tough all the work concerning the creation of the first Trans-genetic mouse in the country has been made in the department of cellular and molecular science in the Kurdistan Medical Science University, "This is a success in scientific arena for research and study in fields of detection and treatment of diseases and developing drug effectiveness."

Dr. Teib-e-Ghadimi added that the color of the trans-genetic mouse at birth was green. He further explained that the new development is "the beginning of a scientific triumph for researchers in the province and the country."

The Kurdistan University of Medical Sciences was established in 1986 as a research and training center in Kurdistan. In 1992, the institution was further elevated to a health and medical university.

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