This year the National Science Digital Library is honored to embark on a collaboration with the The Society for Science and the Public (SSP), one of the nation’s oldest and most-respected educational organizations. SSP’s vision is to promote the understanding and appreciation of science and the vital role it plays in human advancement: to inform, educate, inspire.
Founded as Science Service in 1921, SSP has through its award-winning magazine, Science News
, and through world-class science education competitions—including the Intel International Science and Engineering Fair (ISEF) and the Intel Science Talent Search, both sponsored by the Intel Corporation —conveyed the excitement of all areas of science and research directly to the public.
Our partnership with SSP begins with a special exhibit in the NSDL Wiki, devoted to the 2008 ISEF, which featured over 1200 science and engineering projects from students all over the world. In this NSDL Imprint blog we feature full descriptions of the three top finalists of the Intel ISEF for 2008 along with the top finalists in each of 20 specific award categories. Complete abstracts and bibliographic information on over 1200 projects created by tomorrow’s scientists, engineers, and teachers are available through the Intel ISEF 2008 Exhibit on the NSDL Wiki. We invite all of our patrons, and especially high school science teachers, to use the detailed descriptions of these amazing projects to inspire students to get busy in the field and in the lab!
Intel Foundation Young Scientist Award
The winners of this award are the top three finalists at the Intel ISEF.
Development of Biosensors for Detecting Hazardous Chemicals**also top project for Environmental Science
Natalie Saranga Omattage, 17, The Mississippi School for Mathematics and Science, Columbus, Mississippi
Food additives contaminated with cyanuric acid and melamine were responsible for recent deaths of many pets. Food imports are currently being screened using chromatographic and mass spectrometric methods (e.g. HPLC & GC-MS/MS). Although these methods are very sensitive, the instruments as well as the reagents are expensive and require highly trained personnel to operate. A recombinant M13 bacteriophage library was screened to identify peptide sequences with h igh affinity to cyanuric acid and melamine. Amino acid sequences STNFFYQTFAFH and RNSNHTAYGEEP were identified as the consensus sequences specific to cyanuric acid and melamine, respectively. Quartz crystal microbalance (QCM) based biosensors were developed using these peptides. Although cyanuric acid binding peptide demonstrated better mass accumulation rates than the melamine binding peptide, both peptides were capable of detecting their respective ligands at concentrations as low as 1.25 parts per billion (ppb) during the first five minutes of the experiment. Cyanuric acid and Melamine binding peptides coupled to a gold binding peptide sequence are currently being developed to increase the peptide density and sensitivity of the assay. Biosensors with synthetic peptides could decrease the detection limit to picomolar concentrations of the ligands. QCM instruments are portable, cost much less than GC-MS setups, and do not require highly trained personnel to operate. Therefore, QCM based biosensors may be used at ports and warehouses to more thoroughly screen food additives imported into the United States. In addition to food contaminants, the QCM based biosensors may also be employed to detect other harmful chemicals.
See Ms. Omattage discuss her work on YouTube
Computation of the Alexander-Conway Polynomial on the Chord Diagrams of Singular Knots**also top project for Mathematics
Sana Raoof, 17, Jericho High School, Jericho, New York
The inherent complexity of ambient isotopies, as outlined by the Reidemeister moves, necessitates the use of knot invariants to discriminate between planar representations of mathematical knots. The concept of finite-type invariants reduces the computation of the Alexander-Conway polynomial to the level of combinatorial objects called chord diagrams. In this research, some relations are proven for the delta invariant, which is the formal logarithm of the Alexander-Conway polynomial. The specific family of chord diagrams, denoted Sk,m, contains two disjoint sets of chords arranged in a lattice pattern. Sk,m chord diagrams are characterized by complete bipartite intersection graphs. This paper shows that delta(Sk,m)= 0 for k not equal to m = m!(m-1)! for k=m The theorems presented in this paper increase our knowledge of the Alexander-Conway polynomial invariant for chord diagrams, as well as prove when the invariant can be accurately used to guarantee knot equivalence. These findings pertain to the indentification of tangled organic molecules such as DNA and RNA, and are applicable to the Protein Folding Problem.
See Ms. Raoof discuss her work on YouTube
Efficient Hydrogen Production Using Cu-Zn-Al Catalysts Prepared by Homogeneous Precipitation Method **also top project for Chemistry
Yi-Han Su, 17, Taipei Municipal First Girls’ Senior High School, Taipei, Chinese Taipei
In industry, high-activity catalyst is desirable for methanol reforming reaction in order to generate hydrogen efficiently. In this project, multi-composition Cu-Zn-Al catalyst was synthesized by homogeneous precipitation (HP) method with urea treatment. In comparison with those obtained from conventional co-precipitation method, our technique offers an opportunity to improve the homogeneity of metal mixing and to increase the surface area of catalysts. By adjusting urea concentration, water amount, reaction temperature and time, various hydrotalcite-like compounds are obtained. The optimized catalysts having flower-like morphology, exhibited high surface area (78.5 m^2/g, as determined by Brunauer-Emmett-Teller method), and a lower reduction temperature. The HP-method derived Cu-Zn-Al catalyst exhibited higher methanol-conversion, hydrogen-production-rate and CO2-selectivity under methanol reforming reaction at 523K compared with those derived by co-precipitation method. To further improve the catalytic performance of the Cu-Zn-Al, Ce and Zr were employed to modify the support. The Ce/Zr-modified catalysts did show higher activity, as evidenced by a 20K lower reduction temperature and more than 85% of methanol conversion. Our method can be generalized for the synthesis of other multi-composition materials with high homogeneity.
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Seaborg SIYSS Award
The Ability to Learn: Learning and Communication between Comet Goldfish**also top project for Behaviors/Social Science
Kaleigh Anne Eichel, 17, Strongsville Senior High School, Strongsville, Ohio
This project examines whether goldfish have the ability to learn to perform a simple task and then transfer this learned information to unlearned members of the same species. Firstly, the largest goldfish from a group of five was separated into an isolated aquarium with identical environmental conditions. The environment was then altered through the introduction of a maze and the lone goldfish was trained to swim through the maze using food as a stimulus and positive reinforcement in operant conditioning. The fish was able to successfully complete the maze in an average time of thirty-two seconds. Secondly, two fish were randomly selecting from the original group and introduced into the aquarium of the trained fish. Without a stimulus from human intervention, the newly introduced fish partially learned the maze through the deliberate actions of the trained fish. The larger trained fish would repeatedly swim forward and backward through the opening of the maze to encourage the others to follow its behavior and it would coral the others towards the maze opening. Thirdly, the two fish were removed and a new untrained fish was introduced into to the aquarium of the trained fish. This case found that the transfer of learning was more pronounced for a single unlearned fish compared to two unlearned fish. This project found that fish learn through mimicking the behavior of a learned fish and that there is a tendency of the learned fished to actively influence the learning of the unlearned fish.
Real-Time Water Wave Simulation with Surface Advection**also top project for Computer Science
Dongyoung Kim, 17, Korean Minjok Leadership Academy, Anheung, Gangwon, South Korea
We present a real-time physical simulation model of water surface with a novel algorithm to represent the water mass flow in full three dimensions. The embodiment of general surface advection is an important part of our physics system; however it is an aspect commonly neglected in previous models of water surface, mainly due to computational cost reasons. The physical state of the surface is represented by a set of two dimensional fields of physical values, including height, velocity, and the gradient. The evolution of the velocity field is handled by a velocity solver based on the Navier Stokes Equations. We integrate the principle of the mass conservation in a fluid of equilateral density to update the height field from the unevenness of the velocity propagation, which in mathematical terms can be represented by the divergence operator. Thus the model generates waves induced by horizontal velocity, offering a simulation that puts force added in all direction into account when calculating the values for height and velocity for the next frame. Other effects such as reflection off the boundaries, and interactions with floating objects are involved in the algorithm. The implementation demonstrates to run with fast algorithm speed scalable to real-time rates even for large simulation domains. Therefore, our model is appropriate for a real-time and large scale water surface simulation into which the animator wishes to visualize the global fluid flow as a main emphasis.
Engineering a Novel Gram-Negative Effective Efflux Pump Inhibitor**also top project for Microbiology
Eric Nelson Delgado, 18, Bayonne High School, Bayonne, New Jersey
The emergence of bacterial multidrug resistance pumps (MDRPs) is a growing problem in the treatment of infectious diseases. One attractive treatment option for bacteria which have developed these MDRPs is the use of efflux pump inhibitors (EPIs) such as 5’-methoxyhydnocarpin (5’-MHC), a natural EPI only shown effective in gram-positive bacteria. However, many known EPIs are natural products which are large and hydrophilic. It seems these qualities prevent them from being effective in gram-negative bacteria because the compounds are not able to permeate the outer membrane, which is absent in gram-positive bacteria. The aim of this study was to engineer a derivative of 5’-MHC which is able to permeate the outer membrane of E. coli while retaining the inhibitory activity of the original 5’-MHC molecule. The AcrB efflux pump expressed in E. coli was studied. The effectiveness of all molecules tested was determined utilizing an active transport assay and MIC90 tests. To illustrate the importance of the outer membrane to a molecule’s effectiveness, these experiments were performed on both membrane intact and membrane compromised bacteria. Experiments demonstrated that 5’-MHC was effective in membrane compromised cells, but not in membrane intact cells. This indicates that the impermeability of the outer membrane was indeed a barrier for the molecule’s effectiveness in inhibiting the AcrB. Also, 4’-isoproxyflavone, the molecule selected to have the most potential to enter the cell via diffusion across the outer membrane, was shown to be more effective than 5’-MHC in membrane compromised E. coli, but not at all effective in membrane intact E. coli. Finally, diosmetin, the molecule selected to have the most potential to cross the outer membrane via a porin channel, was equally as effective as 5’-MHC in both membrane intact and membrane comprised E. coli. Thus, diosmetin was identified as a gram-negative effective EPI.
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European Union Contest for Young Scientists
Protection of Neurons Against Injury Using Neuroreceptor-Targeting Nanoparticles**also top project for Team Projects
Jared Vega Goodman, 17, Oak Hall School, Gainesville, Florida
Jonathan Wang, 16, Oak Hall School, Gainesville, Florida
During traumatic brain injury, neurons are injured or killed by excessive amount of glutamate. Neuroprotectants can be used to rescue the neurons. Yet they are not consistently taken in by only neurons and might be relatively unstable in the circulation. In the previous year’s experiment, a device was designed to be used in the targeted delivery of the neuroprotectants to neurons. This device was an immunoliposome, which was an antibody attached to a liposome. The antibody specifically attached to a receptor on the surface of neurons alone, while the liposome was a hollow nanosphere that encapsulated a chemical and released it into the neurons. Fluorescent dyes to show that the contents of the liposomes were successfully delivered to the neurons, proving the success of the targeted delivery device. In this year’s experiment, the hypothesis was that if drugs were used instead of fluorescent dyes, then the immunoliposomes could be used to alleviate the harmful effects of glutamate or analogue N-methyl-D-Aspartate (NMDA) (excitotoxins) by using targeted delivery to help the drugs reach the neurons. The hypothesis was confirmed: cells treated with drug-loaded immunoliposomes showed the least amount of damage. The cells that were treated with the immunoliposomes had less breakdown of an essential protein in the cytoskeleton (alphaII-spectrin), while the cells that had not been treated with the liposomes had a much greater amount of breakdown of this protein. The results indicate that the neuron-targeting immunoliposomes are an effective method of alleviating the neuronal cell injury caused by excitotoxin.
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Animal Sciences - Presented by Intel Foundation
Catch Me If You Can: A Robotic Simulation of Predator-Prey Co-Evolution
Carlie Alexandra Scalesse, 18, London Central Secondary School, London, Ontario, Canada
Behavioural evolution has been a topic of much interest within the scientific field. However, difficulties that arise during the study of the biological evolution of complex organisms, namely its duration, have made studying this an unwieldy process virtually impossible to study in real time. As such, science has turned to artificial life in order to simulate this lengthy process in a shorter time frame. This project aims at determining the efficiency of evolutionary robotics in reproducing the behavioural evolution in a predator-prey co-evolutionary dynamic. Analysis of the results demonstrates that, as hypothesized, an arms race has developed between the predator and prey populations. This arms race lead to the development of actual behaviours used by various species of biological predators. Using evolutionary robotics, a realistic simulation of predator-prey co-evolution has been created. This process can therefore be applied to the study of macro and micro evolution either to better understand evolution, or even to predict it.
Read Full Article the Young Scientists Journal
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Behavioral and Social Sciences - Presented by Intel Foundation
The Ability to Learn: Learning and Communication between Comet Goldfish
Kaleigh Anne Eichel, 17, Strongsville Senior High School, Strongsville, Ohio
This project examines whether goldfish have the ability to learn to perform a simple task and then transfer this learned information to unlearned members of the same species. Firstly, the largest goldfish from a group of five was separated into an isolated aquarium with identical environmental conditions. The environment was then altered through the introduction of a maze and the lone goldfish was trained to swim through the maze using food as a stimulus and positive reinforcement in operant conditioning. The fish was able to successfully complete the maze in an average time of thirty-two seconds. Secondly, two fish were randomly selecting from the original group and introduced into the aquarium of the trained fish. Without a stimulus from human intervention, the newly introduced fish partially learned the maze through the deliberate actions of the trained fish. The larger trained fish would repeatedly swim forward and backward through the opening of the maze to encourage the others to follow its behavior and it would coral the others towards the maze opening. Thirdly, the two fish were removed and a new untrained fish was introduced into to the aquarium of the trained fish. This case found that the transfer of learning was more pronounced for a single unlearned fish compared to two unlearned fish. This project found that fish learn through mimicking the behavior of a learned fish and that there is a tendency of the learned fished to actively influence the learning of the unlearned fish.
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Biochemistry - Presented by Agilent Technologies
Isolation of the Role of Earthworms in the Chemical Alteration Trajectory of Lignin in Old and Young Forest Systems
Russell B. Conard, 18, William Henry Harrison High School, West Lafayette, Indiana
Invasive earthworm activity has been shown to shift forest ecology by altering the rate of litter decomposition, organic carbon content of soil, and impact of fungi and bacteria. A microscale chemical analysis of the role of earthworms in litter decomposition in forest ecosystems is lacking and may provide insight into the macroscale role of forests in the global carbon cycle. This research suggests a direct correlation between invasive earthworm activity and the chemical alteration trajectory of forest litter undergoing decomposition. The analysis of lignin decay in forest floor litter was determined using an isotope-tagging chemolysis mass spectrometry technique with modification to include a semi-automated data extraction and analysis method with direct graphical export developed during the course of this research. The influence of earthworms can be studied by analyzing samples from forest systems known to have native or invasive species. Also, earthworm activity was isolated from other factors by analyzing open air samples (which permit earthworm decay) and samples in litter bags (which eliminate the influence earthworms). This research showed that earthworm activity inhibits lignin decomposition by fungi, causing it to accumulate with respect to low earthworm sites. Background microbial activity assessed by litter bag studies demonstrated differences between high and low earthworm sites; however, the major litter alteration trajectories were related to earthworm activity. These findings suggest that invasive earthworms are altering the rate and nature of litter decay and thereby interrupting the established organic carbon cycling pathways in these forests. Long term implications are yet to be determined.
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Cellular & Molecular Biology - Presented by Intel Foundation
The Novel Role of the GluCl-α Ion Channel and Diazepam-binding Genes in Alcohol Addiction
Kapil Vishveshwar Ramachandran, 16, Westwood High School, Austin, Texas
Alcoholism is a global problem that, each year, consumes more than 200 million dollars and wastes thousands of lives. However, the genetic cause of addiction is still not fully understood. This study was conducted to further understand the mechanisms underlying alcohol tolerance, a primary component of addiction, and to identify genes important for producing tolerance. To understand tolerance, Drosophila melanogaster, the common fruit fly, was used to identify genes that are important for normal alcohol responses. A novel behavioral assay, based on phototaxis, was constructed and optimized to test for ethanol tolerance in Drosophila. With this assay, mutant flies, such as those with chromosomal aberrations and excisions were screened. The result of the behavioral screening was the identification of a mutant, df-7589, that did not acquire tolerance to ethanol. This mutant has a deletion that removes nine genes, five of which are described as being related to a diazepam- binding protein family. The transcriptional responses of these five genes to ethanol were measured through RNA extraction, gel electrophoresis, reverse transcription, and real-time PCR. These data, together with known interactions between diazepam and ethanol, suggest that Diazepam-binding proteins are necessary for ethanol tolerance. I then analyzed the molecular pathways through which Diazepam-binding proteins act, in order to further our understanding of tolerance and alcoholism. Using RNAi gene-knockdown assays and P-element induced mutations specific to the Diazepam-binding genes in the deficiency, I have been screening point mutants to test my hypothesis. I have recently implicated a pathway involved in ethanol responses and corresponding Diazepam-binding gene mediated activity of these responses. The gene, GluClα, encodes a Glutamate-Gated Chloride Channel, a recently discovered molecular pathway. I am now working on conclusively proving the pathways’ co-involvement with Diazepam-binding proteins in modulating the effects of ethanol. In the long run, I hope to use this knowledge to find a cure for alcoholism.
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Chemistry - Presented by Intel Foundation
Efficient Hydrogen Production Using Cu-Zn-Al Catalysts Prepared by Homogeneous Precipitation Method
Yi-Han Su, 17, Taipei Municipal First Girls’ Senior High School, Taipei, Chinese Taipei
In industry, high-activity catalyst is desirable for methanol reforming reaction in order to generate hydrogen efficiently. In this project, multi-composition Cu-Zn-Al catalyst was synthesized by homogeneous precipitation (HP) method with urea treatment. In comparison with those obtained from conventional co-precipitation method, our technique offers an opportunity to improve the homogeneity of metal mixing and to increase the surface area of catalysts. By adjusting urea concentration, water amount, reaction temperature and time, various hydrotalcite-like compounds are obtained. The optimized catalysts having flower-like morphology, exhibited high surface area (78.5 m^2/g, as determined by Brunauer-Emmett-Teller method), and a lower reduction temperature. The HP-method derived Cu-Zn-Al catalyst exhibited higher methanol-conversion, hydrogen-production-rate and CO2-selectivity under methanol reforming reaction at 523K compared with those derived by co-precipitation method. To further improve the catalytic performance of the Cu-Zn-Al, Ce and Zr were employed to modify the support. The Ce/Zr-modified catalysts did show higher activity, as evidenced by a 20K lower reduction temperature and more than 85% of methanol conversion. Our method can be generalized for the synthesis of other multi-composition materials with high homogeneity.
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Computer Science - Presented by Intel Foundation
Real-Time Water Wave Simulation with Surface Advection
Dongyoung Kim, 17, Korean Minjok Leadership Academy, Anheung,
Gangwon, South Korea
We present a real-time physical simulation model of water surface with a novel algorithm to represent the water mass flow in full three dimensions. The embodiment of general surface advection is an important part of our physics system; however it is an aspect commonly neglected in previous models of water surface, mainly due to computational cost reasons. The physical state of the surface is represented by a set of two dimensional fields of physical values, including height, velocity, and the gradient. The evolution of the velocity field is handled by a velocity solver based on the Navier Stokes Equations. We integrate the principle of the mass conservation in a fluid of equilateral density to update the height field from the unevenness of the velocity propagation, which in mathematical terms can be represented by the divergence operator. Thus the model generates waves induced by horizontal velocity, offering a simulation that puts force added in all direction into account when calculating the values for height and velocity for the next frame. Other effects such as reflection off the boundaries, and interactions with floating objects are involved in the algorithm. The implementation demonstrates to run with fast algorithm speed scalable to real-time rates even for large simulation domains. Therefore, our model is appropriate for a real-time and large scale water surface simulation into which the animator wishes to visualize the global fluid flow as a main emphasis.
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Earth & Planetary Sciences - Presented by Shell Oil
Gulf Hypoxic Zones: Forecasting with Mathematical and Laboratory Simulations
Bonnie Joyce McLindon, 16, St. Joseph’s Academy, Baton Rouge, Louisiana
The annual process of the formation of hypoxia in the Gulf of Mexico was simulated in a laboratory microcosm to develop a laboratory protocol for predicting the magnitude of a hypoxic zone based on projected amounts of nutrients in the Mississippi River runoff. For the first stage, the addition of nitrogen and phosphorus to pond water caused high algal growth and oxygen production. In the second step, high dissolved oxygen levels showed continued proliferation of algae. In the third step, sunlight for photosynthesis was removed from the microcosm. A source of atmospheric oxygen was removed as well through the placement of sealing wax. After five days in the ‘no sunlight + no atmosphere’ conditions, the water had become representative of the hypoxic hypolimnion. Whether used together or individually, nitrogen or phosphorus caused hypoxic conditions of the natural waters b a factor of two to five times. The laboratory microcosm or mathematical model: A x KR [C**-CE]= A x KT [CE-CH] + KRX x VH x CH can be used to forecast the magnitude and extent of the toxicity of a hypoxic zone based on the projected addition of nutrients, temperature of the water, or lowest life sustaining level of dissolved oxygen in the hypolimnion. This mathematical model is a Lavoisier oxygen mass balances describing the rate and amount of oxygen diffusion through the water column and decomposing in the hypolimnion. The model does not account for the production of oxygen by algae in the epilimnion, therefore the C** value is an immeasurable value which accounts for this production. These two procedures are now effective ways of predicting magnitude and toxicity of a hypoxic zone.
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Electrical & Mechanical Engineering - Presented by Intel Foundation
Developing Scraps IV: The Self-Contained, Robust, Anthropomorphic, Powered Skeleton–Hybridizing a Prototype for Increased Energy Efficiency
Ian Michael Bouligny, 17, Catholic High School, New Iberia, Louisiana
The focus of this study is the development of a lightweight, load-carrying exoskeleton leg based on passive dynamic walkers. Most exoskeletons to date have powered joints. This new design uses passive and quasi-passive elements in the ankle and knee joints, and articulates the hip with a unique lightweight actuator. Quasi-passive joints can dynamically be adjusted for corresponding changes in velocity and terrain. Once the joint has been reconfigured to match the desired speed or terrain it has encountered, it becomes passive. This architecture minimizes the power requirements for planar, bipedal motion by employing a low-mass, energy-efficient design. These designs can be employed in load carrying applications such as firefighting, military, and recreational activities or in physical therapy devices to aid in ankle related injuries.
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Materials Science & Bioengineering - Presented by Intel Foundation
Asymmetric Underpass Which Leads Convection Current
Xing Fang, 17, Fujian Xiamen Shuangshi High School, Xiamen, Fujian, China
Most of the underpasses in the city are constructed using the symmetric structure. In normal condition,there is no ventilation in the middle of such kind of underpass.(but actually there is very little wind).Thus when passers-by come into the underpass,they’d get a feeling of wet and cold as well as frequently smell something unpleasant,which is not only bad for the maintenance of instruments but also for people’s health.While this design can overcome all the weaknesses above. Under the circumstances of the same current speed in the approach, the two sides’ pressure are both the same and the lacking of wind in the transverse path.Such kind of design is based on the knowledge of hydrokinetics, the design puts forward the two types of underpasses: the leading type and the comprehensive type. Theory of the leading type: the current from the right approach is blocked by V-shaped shielding board and thus altered to the left side, forming one-way current through. Theory of the comprehensive type: the curtailment of space in the right approach and the blocking of V-shaped board make the current speed faster and the air pressure smaller, while the left current is altered to the right side because of the resistance in the straight direction, thus forming resultant of forces which promotes the current to flow to the right side. Thanks to the ingenious use of natural wind, the design needn’t consume any other resources which cannot be regenerated.It can also protect the environment and save the limited energy.
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Energy & Transportation - Presented by Shell Oil
A Novel Process to Highly Improve the Bioethanol Production
Christoffer Norn, 20, Lyngby Technical High School, Kgs. Lyngby, Denmark
In 2007 the bioethanol-industry produced 24.5 billion liters of ethanol and 15.4 billion kg of distillers dried grain with solubles (DDGS) – a left-over which can be used for livestock feeding. This co-product does however contain enough carbohydrates to increase the total bioethanol production by 12.2%, thus giving it a huge potential impact on the process economy. The current application of DDGS is associated with a series of problems (high content of fibers, sulfur, phosphorous, possible presence of mycotoxins and high batch variation), that reduces its market value. To avoid some of these problems and to increase the bioethanol production, I have developed a novel protease-based process for simultaneous pretreatment of fibers and protein extraction. This new method can also be used for non-corn derived DDGS. The pretreatment increased the yield of C5/C6-sugars during an enzymatic hydrolysis with a factor of 3.3 and 1.7, respectively. By screening eight different commercial enzyme products, three were chosen for the hydrolysis of pretreated fibers. Different reaction conditions, i.e. enzyme ratio, pH, temperature, enzyme dosage and reaction time were evaluated with response surface and ternary mixture designs. Using optimal conditions, a total sugar yield of 58% was obtained. The hydrolyzed DDGS was readily fermented with Saccharomyces cerevisiae giving approx. 94% yield based upon fermentation of glucose derived from cellulose. The proteolysate enhanced the hydrolysis of the pretreated fibers, resulting in approx. 87% sugar yield, which is very promising for future development. Next step is to characterize which substance(s) is/are responsible for this important effect.
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Environmental Sciences - Presented by Intel Foundation
Development of Biosensors for Detecting Hazardous Chemicals
Natalie Saranga Omattage, 17, The Mississippi School for Mathematics and Science, Columbus, Mississippi
Food additives contaminated with cyanuric acid and melamine were responsible for recent deaths of many pets. Food imports are currently being screened using chromatographic and mass spectrometric methods (e.g. HPLC & GC-MS/MS). Although these methods are very sensitive, the instruments as well as the reagents are expensive and require highly trained personnel to operate. A recombinant M13 bacteriophage library was screened to identify peptide sequences with h igh affinity to cyanuric acid and melamine. Amino acid sequences STNFFYQTFAFH and RNSNHTAYGEEP were identified as the consensus sequences specific to cyanuric acid and melamine, respectively. Quartz crystal microbalance (QCM) based biosensors were developed using these peptides. Although cyanuric acid binding peptide demonstrated better mass accumulation rates than the melamine binding peptide, both peptides were capable of detecting their respective ligands at concentrations as low as 1.25 parts per billion (ppb) during the first five minutes of the experiment. Cyanuric acid and Melamine binding peptides coupled to a gold binding peptide sequence are currently being developed to increase the peptide density and sensitivity of the assay. Biosensors with synthetic peptides could decrease the detection limit to picomolar concentrations of the ligands. QCM instruments are portable, cost much less than GC-MS setups, and do not require highly trained personnel to operate. Therefore, QCM based biosensors may be used at ports and warehouses to more thoroughly screen food additives imported into the United States. In addition to food contaminants, the QCM based biosensors may also be employed to detect other harmful chemicals.
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Environmental Management - Presented by Kendeda Fund
Kinetics of Bioremediation and Electricity Production in a Novel Microbial Fuel Cell
Timothy Zuchi Chang, 16, Stuyvesant High School, New York, New York
Our wastewater is a feast for billions of bacteria, and this abundant biological resource can be a source of clean energy. A microbial fuel cell (MFC) is an anaerobic bioreactor in which bacteria oxidize substrates to produce free electrons, or electricity. An added benefit of this process is bioremediation, removing pollutants from wastewater before discharging it into the environment. Optimal designs and conditions for MFC operation are not yet fully defined. This research begins to analyze how enhancing biofilm growth and substrate consumption can improve the bioremediation and electricity-production from wastewater-fueled MFCs. To accomplish this, a novel, low-cost fuel cell with a large anode surface area was designed. Nutrient consumption tests and efficiency measurements obtained in this research will be used to improve future reactor designs. Prior to inoculation with anaerobic digester sludge, several MFCs were prepared with various electron acceptors to encourage extracellular electron deposition. Biofilm from the MFC producing the most power was used to seed later generations of fuel cells, to select the most efficient bacterial community. Tests were performed to define carbon and nitrogen consumption rates (the bioremediation process). The MFC enriched with iron (iii) chloride, FeCl3, produced the most power, approximately 1.2 W/m2. Added nitrogen and carbon were consumed within 72 hours with 62 percent voltaic efficiency. Thus, 62 percent of the energy in a glucose molecule was converted to electricity. This suggests selective pressures on electricity-producing microbial communities will improve MFC efficiency for power output and wastewater treatment.
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Mathematical Sciences - Presented by Intel Foundation
Computation of the Alexander-Conway Polynomial on the Chord Diagrams of Singular Knots
Sana Raoof, 17, Jericho High School, Jericho, New York
The inherent complexity of ambient isotopies, as outlined by the Reidemeister moves, necessitates the use of knot invariants to discriminate between planar representations of mathematical knots. The concept of finite-type invariants reduces the computation of the Alexander-Conway polynomial to the level of combinatorial objects called chord diagrams. In this research, some relations are proven for the delta invariant, which is the formal logarithm of the Alexander-Conway polynomial. The specific family of chord diagrams, denoted Sk,m, contains two disjoint sets of chords arranged in a lattice pattern. Sk,m chord diagrams are characterized by complete bipartite intersection graphs. This paper shows that delta(Sk,m)= 0 for k not equal to m = m!(m-1)! for k=m The theorems presented in this paper increase our knowledge of the Alexander-Conway polynomial invariant for chord diagrams, as well as prove when the invariant can be accurately used to guarantee knot equivalence. These findings pertain to the indentification of tangled organic molecules such as DNA and RNA, and are applicable to the Protein Folding Problem.
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Medicine and Health Sciences - Presented by Intel Foundation
Alternative Splicing Defects Linked to Amyotrophic Lateral Sclerosis
Alicia Marie Darnell, 17, Pelham Memorial High School, Pelham, New York
Amyotrophic lateral sclerosis is a neurodegenerative disease of unknown cause, with the exception of 2% of cases that are caused by a dominantly inherited mutation in the superoxide dismutase 1 gene (SOD1). There has been speculation that alternative splicing defects could play a role in the pathogenesis of ALS, but definitive data has never been obtained in genetically affected individuals. To develop an assay for this possibility, gene transcripts important in lower motor neuron function were examined in SOD1 mutant mice. Alternative splicing defects were identified in four out of four SOD1 mice but in zero of four control animals. Quantitation of PCR products confirmed that on average, 1.5-2 fold changes in splicing of Chl1, Agrin, and LAR spinal cord mRNA transcripts were present. Since these genes code for proteins that play a role in motor neuron synapse formation and function, the missplicing of these mRNAs in SOD1 mutant mice suggests that alternative splicing defects leading to the production of abnormal motor neuron synapses may play a role in ALS. The identification of these splicing defects may lead to a much needed diagnostic tool and provides new leads towards treatment and better understanding of ALS pathogenesis.
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Microbiology - Presented by Intel Foundation
Engineering a Novel Gram-Negative Effective Efflux Pump Inhibitor
Eric Nelson Delgado, 18, Bayonne High School, Bayonne, New Jersey
The emergence of bacterial multidrug resistance pumps (MDRPs) is a growing problem in the treatment of infectious diseases. One attractive treatment option for bacteria which have developed these MDRPs is the use of efflux pump inhibitors (EPIs) such as 5’-methoxyhydnocarpin (5’-MHC), a natural EPI only shown effective in gram-positive bacteria. However, many known EPIs are natural products which are large and hydrophilic. It seems these qualities prevent them from being effective in gram-negative bacteria because the compounds are not able to permeate the outer membrane, which is absent in gram-positive bacteria. The aim of this study was to engineer a derivative of 5’-MHC which is able to permeate the outer membrane of E. coli while retaining the inhibitory activity of the original 5’-MHC molecule. The AcrB efflux pump expressed in E. coli was studied. The effectiveness of all molecules tested was determined utilizing an active transport assay and MIC90 tests. To illustrate the importance of the outer membrane to a molecule’s effectiveness, these experiments were performed on both membrane intact and membrane compromised bacteria. Experiments demonstrated that 5’-MHC was effective in membrane compromised cells, but not in membrane intact cells. This indicates that the impermeability of the outer membrane was indeed a barrier for the molecule’s effectiveness in inhibiting the AcrB. Also, 4’-isoproxyflavone, the molecule selected to have the most potential to enter the cell via diffusion across the outer membrane, was shown to be more effective than 5’-MHC in membrane compromised E. coli, but not at all effective in membrane intact E. coli. Finally, diosmetin, the molecule selected to have the most potential to cross the outer membrane via a porin channel, was equally as effective as 5’-MHC in both membrane intact and membrane comprised E. coli. Thus, diosmetin was identified as a gram-negative effective EPI.
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Physics and Astronomy - Presented by Intel Foundation
Great Balls of Fire II
Caroline Julia von Wurden, 16, Los Alamos High School, Los Alamos, New Mexico
I studied free-floating ball plasmas in the laboratory, created by an electric discharge from points of metal near a water surface, using cameras, photodiodes, power meters, and spectroscopy. The lifetime, brightness, and size of the plasma were varied with different geometries of electrodes and buckets, as a function of voltage. Air is excluded from the plasma (no nitrogen or oxygen lines are seen in the ball spectroscopically). The plasma’s boundary layer changed when launched into Helium instead of air. With laser mirrors to form a cavity around the ball plasma, I looked for copper laser action at the 510.6 nm Cu I line, but did not see evidence for lasing action. Long lived free-floating plasmas are generated above a bucket of water containing a weak solution of Copper Chloride, using copper electrodes. The plasma consists of positive salts from the solution and center electrode material, and negative hydroxyl radicals. I thought that a bigger plasma could be made in a bucket with more surface area, but this was not true. A better scaling knob is the applied voltage. I made plasmas with discharge currents ranging from 4 Amps to 250 Amps, as I increased the applied voltage up to 5kV. The plasmas became brighter, and somewhat larger. Dusty orange colored filamentary structures can be seen inside the glowing green plasma. When the bucket is surrounded by a bag of helium to exclude air, the orange boundary layer (seen in the air case) disappears.
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Plant Sciences - Presented by Intel Foundation
Risk Assessment of Bt Transgenic Brassica: Effect on Target and Nontarget Insects and Use of SSR Molecular Markers to Assess Cross-Compatibility and Outcrossing Potential of Brassica Accessions
Hemali Chandramohan Batra, 17, Central Campus, Des Moines, Iowa
The concerns of the international community regarding bioengineered plants necessitate risk assessments of Bt transgenic Brassica, in which I combined entomology and molecular genetics to research their impact on flora and fauna of surrounding environments. Due to the weakening or premature death of Plutella xylostella larvae from ingestion of Bt crystal toxin proteins, they cannot serve as viable pupal hosts for the development of Diadromus collaris endoparasitoid eggs, resulting in a decreased rate of percent parasitism. Because prevailing studies on the impact of Bt toxin ingestion by target insects on non-target insects have been largely inconclusive, this result of effectively controlled nontarget pest populations with fewer female offspring to sustain future endoparasitoid populations is significant. Because the likelihood that Plutella xylostella can develop resistance to multiple toxin proteins in a gene-pyramided transgenic plant is minimal, Bt crops present a long-term solution for pest management. In addition, I used microsatellite, or simple sequence repeat (SSR), molecular markers to formulate a dendrogram depicting genetic relationships among thirty-two Brassica accessions. Determining the outcrossing potential and cross-compatibility of accessions is integral in the risk assessment of Bt transgenic Brassica because the international community is wary of the possible consequence of transgene escape through hybridization resulting from the release of transgenic plants into the environment. Knowledge of accessions’ outcrossing potential will define future risk assessments involving experimental crosses of accessions. If accessions are not reproductively compatible in nature, the concerns of the international community regarding the threat of transgene escape to biodiversity can be alleviated.
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Team Projects - Presented by Science News
Improving the Feasibility of Avalanche Gain X-Ray Detectors
Shai Matthew Chester, 17, Yeshiva University High School for Boys,
New York, New York and Elie Joshua Bochner, 18, Yeshiva University High School for Boys,
New York, New York
Flat panel x-ray detectors for digital radiography have been used in the clinic for nearly a decade and enable the rapid acquisition of high-resolution x-ray images with excellent contrast. However, current detectors are optimized for imaging applications that use high detector entrance exposures to produce large signals capable of overcoming the electronic noise associated with the thin film transistor (TFT) readout process. A novel indirect x-ray detector concept, referred to as SHARP-AMFPI (Scintillator – High-Gain Avalanche Rushing Photoconductor), utilizes variable x-ray to charge conversion gain from a thin layer of amorphous selenium (a-Se) to create a detector compatible with multiple dosage radiographic procedures. However, variations in the TFT array’s surface topography result in non-uniform conversion gain, which dramatically decreases the quality of produced images. We propose to use thin-films of polyaniline (PANI-EB), an intrinsically conductive polymer, as a planarization layer between the a-Se and ITO pixel electrode on the TFT array. Using a contact angle measurement device, we determined the optimal cleaning method to improve the wetting of the ITO substrate with the PANI-EB solution. The surface topography and thicknesses of spun-cast PANI films on various substrates were measured with atomic force microscopy, and the attenuation of the film-covered substrate’s surface corrugation was similarly monitored. The results of this study suggest that polyaniline films could be utilized to planarize the TFT array in SHARP-AMFPI; however, further work is needed to determine if PANI thin films are best suited to create a flat-panel x-ray detector with variable gain.
Protection of Neurons Against Injury Using Neuroreceptor-Targeting Nanoparticles
Jared Vega Goodman, 17, Oak Hall School, Gainesville, Florida and Jonathan Wang, 16, Oak Hall School, Gainesville, Florida
During traumatic brain injury, neurons are injured or killed by excessive amount of glutamate. Neuroprotectants can be used to rescue the neurons. Yet they are not consistently taken in by only neurons and might be relatively unstable in the circulation. In the previous year’s experiment, a device was designed to be used in the targeted delivery of the neuroprotectants to neurons. This device was an immunoliposome, which was an antibody attached to a liposome. The antibody specifically attached to a receptor on the surface of neurons alone, while the liposome was a hollow nanosphere that encapsulated a chemical and released it into the neurons. Fluorescent dyes to show that the contents of the liposomes were successfully delivered to the neurons, proving the success of the targeted delivery device. In this year’s experiment, the hypothesis was that if drugs were used instead of fluorescent dyes, then the immunoliposomes could be used to alleviate the harmful effects of glutamate or analogue N-methyl-D-Aspartate (NMDA) (excitotoxins) by using targeted delivery to help the drugs reach the neurons. The hypothesis was confirmed: cells treated with drug-loaded immunoliposomes showed the least amount of damage. The cells that were treated with the immunoliposomes had less breakdown of an essential protein in the cytoskeleton (alphaII-spectrin), while the cells that had not been treated with the liposomes had a much greater amount of breakdown of this protein. The results indicate that the neuron-targeting immunoliposomes are an effective method of alleviating the neuronal cell injury caused by excitotoxin.
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