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New Science and Technology Achievements

Sunday, January 30, 2011

Compiled By: Firouzeh Mirrazavi
Deputy Editor of Iran Review

*Breakthrough in Treating Tuberculosis

Active ImageIranian researchers at Shiraz Medical University made a breakthrough in treating tuberculosis.

Dr. Mehdi Khoshnevis-Zadeh, who led the research, said tuberculosis is a leading infectious cause of death worldwide.

“Because of the concern of the resistance to most of the commonly used drugs displayed by the mycobacteria, most efforts have been made to introduce new anti-tubercular agents,” he said.

He also said recent studies showed that 1, 4-dihydropyridine-3,5-dicarbamoyl derivatives with lipophilic groups have significant anti-tubercular activity.

“In this study, we synthesized new derivatives of 1, 4-dihydropyridines in which different alkyl and aryl esters and diethyl carbamoyl are substituted in C-3 and C-5 of the DHP ring,” he said.

“In addition, nitroimidazole ring is a substitute at C-4 position,” he said, adding that these asymmetric analogues were synthesized by a modified Hantzsh reaction using procedure reported by Meyer.

He further said the in-vitro anti-tubercular activity of compounds against mycobacterium tuberculosis was evaluated, adding that the results indicate that the compounds containing aromatic esters are more potent than alkyl ones.

“The most potent aromatic compound (R=3-phenylpropyl) exhibits comparable anti-tubercular activity (MIC=1 micromol/ml) with reference compound isoniazide (INH) (MIC=1 micromol/ml),” he said.

Khoshnevis-Zadeh concluded that studies of these compounds showed that the increasing lipophilicity and rotable bonds of these compounds resulted in increasing anti-tubercular activity.

Active Image*Breakthrough in Treating Ureteropelvic Obstruction

Iranian researchers at Shahid Labbafinejad Medical Center of Shahid Beheshti University have made a breakthrough in treating ureteropelvic junction obstruction.

Dr. Nasser Simforoush, who led the research, said it was intended to demonstrate our experience in laparoscopic management of ureteropelvic junction obstruction by division of the aberrant vein and cephalad relocation of the crossing artery in a large group of patients with long-term follow-up.

“Three hundred and twenty-nine patients were candidates for laparoscopic transperitoneal ureteropelvic junction obstruction management,” he said. “Intraoperatively, lower pole crossing vessels were identified in 117 patients (35.5 percent).” He added that after the division of the aberrant vein, the crossing artery was relocated and fixed to peripelvic tissue.

Simforoush said renal pelvic emptying with pyeloureteral peristalsis was considered in 71 patients, so neither pyeloplasty nor Double-J stent was fixed for them, adding that postoperative outcomes were assessed with intravenous urography and/or diethylene triamine pentaacetic acid-diuretic renal scan.

He explained that of the 71 patients who underwent this laparoscopic approach, 42 were completely followed over a long-term period. The mean age of patients was 27 years. “The mean operative duration was 133 (55–185) minutes and blood loss was negligible,” he said. He added that the mean hospital stay was 2.8 (1–7) days and the mean followup was 29 (3–84) months. Overall success rate was 90 percent and recurrence of obstruction was noted in two patients. No significant complications were observed.

Simforoush said cephalad relocation of the lower pole crossing artery after division of the crossing vein in selected cases could be an ideal alternative for dismembered pyeloplasty with noticeable outcomes in long-term follow-up.

Active Image*Extending Shelf Life Of Fresh Orange Juice

Iranian researchers at Isfahan University of Technology extended the shelf life of fresh orange juice up to 28 days by antimicrobial nanocomposite packages.

Aryou Emamifar, who led the research, explained that nanocomposite LDPE films containing Ag and ZnO nanoparticles were prepared by melt mixing in a twin-screw extruder.

“Packages prepared from the films were then filled with fresh orange juice and stored at 4 °C,” he said.

“Microbial stability, ascorbic acid (AA) content, browning index, color value, and sensory attributes of them were evaluated after 7, 28, and 56 days of storage.”

He also said packages containing the nanomaterials, expect 1 percent nano-ZnO, kept the microbial load of fresh juice below the limit of microbial shelf life (6 log cfu/ml) up to 28 days.

He further said the least degradation of AA (80.50 mg/100 g), development of brown pigments (OD = 0.23) and losing of color (∆E = 6.0) were observed in pouches containing 0.25 percent nano-ZnO, after the same time.

He added that sensory attributes were also ranked highest for the juice thus packed in the recent packages after 28 days (p < 0.05). He said packages containing nanosilver increased shelf life of fresh juice although part of its sensory attributes were lost.

He concluded that compared with pure packaging materials, antimicrobial nanocomposite packages containing Ag and ZnO as an alternative non-thermal technology can extend the shelf life of fresh orange juice up to 28 days.

“However, a certain concentration of nano-ZnO in the packages showed less adverse effects on sensory characteristics,” Emamifar said.

Active Image*Iranians Produce 2 New Radiomedicines

Iranian scientists have synthesized two new types of radiomedicines to treat malignant cancers.

Atomic Energy Organization of Iran (AEOI) Spokesman Hamid Khadem Qaemi said that Iranian scientists and researchers of the AEOI’s Nuclear Science and Technology Research Center succeeded in producing two new radiomedicines for the first time to cure malignant cancers.

He named these radiomedicines as lutetium-177 phosponate (EDTMP) for bone pain palliation in metastatic prostate cancer and iodine 131 chlorotoxin to treat malignant glioma.

Qaemi pointed out that only a few countries are researching about the two radiomedicines or have produced them for treat the aforementioned diseases.

Iran in December unveiled five radiomedicine projects with applications for diagnosis, prevention and treatment of a number of diseases.

In September, Iran announced that it plans to synthesize 20 kinds of radiomedicines inside the country, stressing that its scientists are capable of supplying the 20 percent-enriched uranium needed for the production of such drugs.

“Iran has gained the necessary preparedness to produce 20 radiomedicines and we will provide the 20 percent (enriched) fuel needed for the production of these medicines this year,” Massoud Akhavan-Fard, the AEOI deputy head for planning, international and parliamentary affairs said in September.

In addition to the Tehran research reactor that has long been involved in radioisotope production, Iran plans to build four other research reactors in other parts of the country.

Active Image*Most Distant Galaxy Cluster Identified

Astronomers have discovered the most distant cluster of galaxies ever observed and at the earliest stage of development yet witnessed.

The proto-cluster--Cosmos-Aztec3--is a burgeoning galactic metropolis that scientists believe grew into a modern galaxy cluster similar to the massive ones seen today. Roughly 12.6billion light-years away from Earth, it is the youngest proto-cluster ever captured. To put this in perspective, our universe is estimated to be 13.7billion years old. Previously the most mature versions of proto-clusters had been spotted at 10billion light-years away.

Iran-born Professor Bahram Mobasher, from the University of California, was one of the international team of astronomers who found Cosmos-Aztec3. He said, “This is a galaxy cluster in the process of formation--a proto-cluster--more than 12billion years ago.

“This proto-cluster was formed about one billion years after the Big Bang. Study of such structures reveals how galaxies came together and merged to form larger galaxies.”

Professor Mobasher and his team identified member galaxies of this cluster and measure their distances and velocities. They also calculated when the proto-cluster was formed by measuring the spectra of candidates in the cluster using the Keck Telescope in Hawaii.

Most galaxies in our universe are bound together into clusters that dot the cosmic landscape like urban sprawls, usually centered around one old, monstrous galaxy containing a massive black hole. Astronomers thought that primitive versions of these clusters, still forming and clumping together, should exist in the early universe. But locating one proved difficult - until now.

The researchers first used the Chandra X-ray Observatory and Britain’s James Clerk Maxwell Telescope on Mauna Kea, Hawaii, to search for the black holes and bursts of star formation needed to form the massive galaxies at the centers of modern galaxy cities. The astronomers then used Hubble and the Subaru telescopes to estimate the distances to these objects, and look for higher densities of galaxies around them. Finally, the Keck telescope was used to confirm that these galaxies were at the same distance and part of the same galactic sprawl. Once the scientists found this lumping of galaxies, they measured the combined mass with the help of Spitzer.

Active ImageAt this distance the optical light from stars is shifted, or stretched, to infrared wavelengths that can only be observed in outer space by Spitzer. The lump sum of the mass turned out to be a minimum of 400billion suns - enough to indicate that the astronomers had indeed uncovered a massive proto-cluster. The Spitzer observations also helped confirm a massive galaxy at the centre of the cluster was forming stars at an impressive rate.

Chandra X-ray observations were used to find and characterize the whopping black hole with a mass of more than 3 million suns. Massive black holes are common in present-day galaxy clusters, but this is the first time a feeding black hole of this size has been linked to a cluster that is so young. Finally, the Institut de Radioastronomie Millimétrique’s interferometer telescope in France and 30-meter telescope in Spain, along with the National Radio Astronomy Observatory’s Very Large Array telescope in New Mexico, measured the amount of gas, or fuel for future star formation, in the cluster.

The results indicate the cluster will keep growing into a modern city of galaxies. Cosmo-Aztec3, located in the constellation Sextans, is named after the region where it was found, called COSMOS after the Cosmic Evolution Survey. AzTEC is the name of the camera used on the James Clerk Maxwell Telescope.

Dr. Mobasher, the Iranian scientist and cosmologist, was born in 1959 in Tehran, Iran.

Active Image*Health Monitoring Contact Lenses on the Way

The next time you gaze deep into someone’s eyes, you might be shocked at what you see: tiny circuits ringing their irises, their pupils dancing with pinpricks of light. These smart contact lenses aren’t intended to improve vision.

Instead, they will monitor blood sugar levels in people with diabetes or look for signs of glaucoma.

The lenses could also map images directly onto the field of view, creating head-up displays for the ultimate augmented reality experience, without wearing glasses or a headset. To produce such lenses, researchers are merging transparent, eye-friendly materials with microelectronics.

In 2008, as a proof of concept, Iran-born Dr. Babak Parviz at the University of Washington in Seattle created a prototype contact lens containing a single red LED. Using the same technology, he has now created a lens capable of monitoring glucose levels in people with diabetes.

“It works because glucose levels in tear fluid correspond directly to those found in the blood, making continuous measurement possible without the need for thumb pricks,” he said. Parviz’s design calls for the contact lens to send this information wirelessly to a portable device worn by diabetics, allowing them to manage their diet and medication more accurately.

Lenses that also contain arrays of tiny LEDs may allow this or other types of digital information to be displayed directly to the wearer through the lens. This kind of augmented reality has already taken off in cellphones, with countless software apps superimposing digital data onto images of our surroundings, effectively blending the physical and online worlds.

Making it work on a contact lens won’t be easy, but the technology has begun to take shape. Last September, Sensimed, a Swiss spinoff from the Swiss Federal Institute of Technology in Lausanne, launched the very first commercial smart contact lens, designed to improve treatment for people with glaucoma.

The disease puts pressure on the optic nerve through fluid build-up and can irreversibly damage vision if not properly treated. “Highly sensitive platinum strain gauges embedded in Sensimed’s Triggerfish lens record changes in the curvature of the cornea, which correspond directly to the pressure inside the eye,” says CEO Jean-Marc Wismer.

“The lens transmits this information wirelessly at regular intervals to a portable recording device worn by the patient.”

The lens gets its power from a nearby loop antenna--in this case taped to the patient’s face. The powered antenna transmits electricity to the contact lens, which is used to interrogate the sensors, process the signals and transmit the readings back.

Each disposable contact lens is designed to be worn just once for 24 hours and the patient repeats the process once or twice a year. This allows researchers to look for peaks in eye pressure which vary from patient to patient during the course of a day. This information is then used to schedule the timings of medication.

Active Image“The timing of these drugs is important,” Wisner says. Parviz, however, has taken a different approach. His glucose sensor uses sets of electrodes to run tiny currents through the tear fluid and measures them to detect very small quantities of dissolved sugar. These electrodes, along with a computer chip that contains a radio frequency antenna, are fabricated on a flat substrate made of polyethylene terephthalate (PET), a transparent polymer commonly found in plastic bottles. This is then molded into the shape of a contact lens to fit the eye.

Parviz plans to use a higher-powered antenna to get a better range, allowing patients to carry a single external device in their breast pocket or on their belt.

Preliminary tests show that his sensors can accurately detect even very low glucose levels. Parvis is due to present his results later this month at the IEEE MEMS 2011 conference in Cancun, Mexico.

“There’s still a lot more testing we have to do,” says Parviz. In the meantime, his lab has made progress with contact lens displays. They have developed both red and blue miniature LEDs--leaving only green for full color--and have separately built lenses with 3D optics that resemble the head-up visors used to view movies in 3D.

Parviz has yet to combine both the optics and the LEDs in the same contact lens, but he is confident that even images so close to the eye can be brought into focus.
“You won’t necessarily have to shift your focus to see the image generated by the contact lens,” says Parviz. “It will just appear in front of you. The LEDs will be arranged in a grid pattern and should not interfere with normal vision when the display is off.” For Sensimed, the circuitry is entirely around the edge of the lens. However, both have yet to address the fact that wearing these lenses might make you look like the robots in the movies. “False irises could eventually solve this problem. But that’s not something at the top of our priority list.”

Parviz was born in Tehran and earned his first degree from Sharif University before coming to the United States to further his education. After earning master’s and doctoral degrees from the University of Michigan, he joined Harvard University’s Department of Chemistry and Chemical Biology as a postdoctoral research fellow in 2001 before taking a faculty position with the University of Washington in Seattle.

Active Image*Lab-on-Chip Can Speed Blood Tests

Researchers of University of Rhode Island have developed a lab-on-a-chip device capable of offering blood test results in under 30 minutes.

Mohammad Faghri, study leader and a professor of mechanical engineering at the University of Rhode Island, along with a team of researchers from the university, have created a portable device that has the potential to eliminate the need for laboratory use when seeking blood test results.

Traditional blood tests taken today require a patient to fill a vial or more of blood that is then sent to a laboratory. It could take several days before results are received, making this process a bit lengthy and expensive. But now, the University of Rhode Island researchers have created a lab-on-a-chip device that only requires a drop of blood, and can deliver results in less than 30 minutes. In addition, the device is small and portable. It consists of a plastic polymer cartridge that is the size of a credit card, and a biosensor that is the size of a shoebox.

“This development is a big step in point-of-care diagnostics, where testing can be performed in a clinic, doctor’s office, or right at home,” said Faghri. “No longer will patients have to wait anxiously for several days for their test results. They can have their blood tested when they walk into the doctor’s office and the results will be ready before they leave.” To do this, a drop of blood is set onto a plastic polymer cartridge. The cartridges were originally designed to detect C-reactive proteins in the blood for risk assessment of peripheral vascular and cardiovascular diseases, but are now capable of detecting biomarkers for other diseases.

The cartridge is then put into a biosensor, which contains a piezoelectric micro-pump and a miniature spectrometer. The blood then flows through channels that are about 500 microns wide until it reaches a detection site where a sensor can identify biomarkers of a disease while the blood reacts with preloaded reagents. In addition to being fast, small and portable, the lab-on-a-chip test is also inexpensive compared to other blood test methods. This test costs about $3,200 for the sensor, and $1.50 for each additional test to replace the cartridge and reagents.

The next step is to work on a new generation of the lab-on-a-chip system, which will provide even more portability at reduced costs. Faghri sees the next generation as being a handheld device, then eventually a smartphone application where the biosensor will be inserted into the cartridge and the processing power of the phone will be used to generate results.

“We are already making progress on many of the steps toward the next generation of the system, and it won’t be long before we can begin to commercialize it,” said Faghri.

Active Image*“Liquid Pistons” Could Drive New Advances in Camera Lenses and Drug Delivery

A few unassuming drops of liquid locked in a very precise game of “follow the leader” could one day be found in mobile phone cameras, medical imaging equipment, implantable drug delivery devices, and even implantable eye lenses.

Engineering researchers at Rensselaer Polytechnic Institute have developed liquid pistons, in which oscillating droplets of ferrofluid precisely displace a surrounding liquid. The pulsating motion of the ferrofluid droplets, which are saturated with metal nanoparticles, can be used to pump small volumes of liquid. The study also demonstrated how droplets can function as liquid lenses that constantly move, bringing objects into and out of focus.

These liquid pistons are highly tunable, scalable, and — because they lack any solid moving parts — suffer no wear and tear. The research team, led by Rensselaer Professor Amir H. Hirsa, is confident this new discovery can be exploited to create a host of new devices ranging from micro displacement pumps and liquid switches, to adaptive lenses and advanced drug delivery systems.

“It is possible to make mechanical pumps that are small enough for use in lab-on-a-chip applications, but it’s a very complex, expensive proposition,” said Hirsa, a professor in the Department of Mechanical, Aerospace, and Nuclear Engineering at Rensselaer. “Our electromagnetic liquid pistons present a new strategy for tackling the challenge of microscale liquid pumping. Additionally, we have shown how these pistons are well-suited for chip-level, fast-acting adaptive liquid lenses.”

Results of the study are detailed in the paper “Electromagnetic liquid pistons for capillarity-based pumping,” recently published online by the journal Lab on a Chip.

Hirsa’s team developed a liquid piston that is comprised of two ferrofluid droplets situated on a substrate about the size of a piece of chewing gum. The substrate has two holes in it, each hosting one of the droplets. The entire device is situated in a chamber filled with water.

Pulses from an electromagnet provoke one of the ferrofluid droplets, the driver, to vibrate back and forth. This vibration, in turn, prompts a combination of magnetic, capillary, and inertial forces that cause the second droplet to vibrate in an inverted pattern. The two droplets create a piston, resonating back and forth with great speed and a spring-like force. Researchers can finely control the strength and speed of these vibrations by exposing the driver ferrofluid to different magnetic fields.

Active ImageIn this way, the droplets become a liquid resonator, capable of moving the surrounding liquid back and forth from one chamber to another. Similarly, the liquid piston can also function as a pump. The shift in volume, as a droplet moves, can displace from the chamber an equal volume of the surrounding liquid. Hirsa said he can envision the liquid piston integrated into an implantable device that very accurately releases tiny, timed doses of drugs into the body of a patient.

As the droplets vibrate, their shape is always changing. By passing light through these droplets, the device is transformed into a miniature camera lens. As the droplets move back and forth, the lens automatically changes its focal length, eliminating the usual chore of manually focusing a camera on a specific object. The images are captured electronically, so software can be used to edit out any unfocused frames, leaving the user with a stream of clear, focused video.

The speed and quality of video captured from these liquid lenses has surpassed 30 hertz, which is about the quality of a typical computer web cam. Liquid lenses could mean lighter camera lenses that require only a fraction of the energy demanded by today’s digital cameras. Along with handheld and other electronic devices, and homeland security applications, Hirsa said this technology could even hold the key to replacement eye lenses that can be fine-tuned using only high-powered magnets.

“There’s really a lot we can do with these liquid pistons. It’s an exciting new technology with great potential, and we’re looking forward to moving the project even further along,” he said.

Along with Hirsa, co-authors on the paper are Rensselaer doctoral graduates Bernard Malouin Jr., now with MIT’s Lincoln Laboratory; and Michael Vogel, a private research consultant; Rensselaer mechanical engineering doctoral student Joseph Olles; and former postdoctoral researcher Lili Cheng, now with General Electric Global Research.

This study was supported with funding from the Defense Advanced Research Projects Agency (DARPA).

Active Image*Hydroponics Technology Indigenized Science Desk

Iranian researchers at Soilless Culture Research Center of Isfahan University of Technology have indigenized hydroponics technology in Iran.

“Hydroponics is a method of growing plants using mineral nutrient solutions in water without soil,” said Bidaki, researcher of the center.

Bidaki noted that terrestrial plants may be grown with their roots in the mineral nutrient solution in an inert medium, such as perlite, gravel, mineral wool or coconut husk.

Plants absorb essential mineral nutrients as inorganic ions in water. In natural conditions, soil acts as a mineral nutrient reservoir but the soil itself is not essential to plant growth.

When the mineral nutrients in the soil dissolve in water, plant roots are able to absorb them. When these nutrients are introduced into a plant’s water artificially, soil is no longer required for the plant to thrive. Almost any terrestrial plant will grow with hydroponics.

Hydroponics is also a standard technique in biology research and teaching. The two main types of hydroponics are solution culture and medium culture, both of which do not use a solid medium for the roots. The three main types of solution culture are static solution culture, continuous flow solution culture and aeroponics.

The medium culture method has a solid medium for the roots and is named for the type of medium, e.g. sand culture, gravel culture or rockwool culture. There are two main variations for each medium, sub-irrigation and top irrigation.

For all techniques, most hydroponic reservoirs are now built of plastic but other materials have been used, including concrete, glass, metal, vegetable solids and wood. The container should exclude light to prevent algae growth in the nutrient solution.

Some of the reasons why hydroponics is being adapted around the world for food production are as follows:

• No soil is needed.
• The water stays in the system and can be reused, lowering water costs.
• It is possible to control the nutrition levels in their entirety, which lowers nutrition costs.
• No nutrition pollution is released into the environment because of the controlled system.
• Stable and high yields.
• Pests and diseases are easier to get rid of than in soil because of the container’s mobility.

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