News Article | April 26, 2017
"Imagine a world in which you print instead of machine your parts." This statement was put to the audience during a presentation at SPIE Defense + Commercial Sensing in April. Part of the Additive Manufacturing for Space Access session, this talk featured the work of Jacob Reimers, an undergraduate student at North Dakota State University (NDSU). Reimer's research focuses on fused filament fabrication (FFF) 3D printing in space. FFF 3D printing could be a practical solution to reducing the mass and volume required for bringing materials into orbit. This capability could bring a fundamental change to space missions. Materials could be launched in a compact, raw form and transformed into the requisite parts and structures, as needed, allowing more material to be transported in a given volume of space -- as compared to packed finished spacecraft. Structures could be designed for only the orbital microgravity environment, which means they wouldn't need to be as durable as on Earth, so would require much less mass. This could make space missions significantly less expensive or have additional capabilities for the same cost. Conceptual printer spacecraft design shown printing truss structure. This research included finding the proper material for 3D printing in space. "As we continued this work, there was a general consensus that Aluminum was the material of choice," said Jeremy Straub assistant professor of computer science NDSU faculty mentor this project. "However, aluminum doesn't have a molten state -- it goes directly from solid to liquid." This is problematic for FFF 3D printing, as this molten state is how the filament is deposited to bond. As noted by NDSU undergraduate Brandon Rudisel in the presentation, an element used for FFF 3D printing needs to hit a ‘Goldilocks zone' of not too hot or cold." This point, called the "glass transition temperature," causes the filament to exhibit pseudo-solid properties. "We identified a metallic glass material that contained aluminum and had a number of properties that were similar to, or better than, aluminum," said Straub. The aluminum alloy consists of aluminum, nickel, and yttrium and is created by melting the three elements together and cooling them at a specific rate. This metallic glass would then be made into a pellet, to prepare it for its transformation into a filament used by a printer. "We don't have testing results on this yet," Straub added, "however, we believe the material will be stronger than aluminum." In terms of what could be printed with this technology, Straub points out that the list of possibilities is "pretty expansive." For example, a structure could be created on demand, in space, to house sensors. This structure could be further customized via lens placement with 3D printed supports, etc. Using a cache of sensors kept on orbit to support rapid missions, they could then be placed with very little delay. "It's a technology that has the potential to create faster, more capable, and lower-cost space missions in Earth's orbit and beyond," said Straub.
Farsani P.M.,NDSU |
Chaudhuri N.R.,NDSU |
Majumder R.,Siemens AG
2016 IEEE Power and Energy Society Innovative Smart Grid Technologies Conference, ISGT 2016 | Year: 2016
Several works have studied the process of system restoration using Voltage Source Converter-based High Voltage Direct Current (VSC-HVDC) links and shown its effectiveness through simulations performed using detailed switched models in software like EMTDC/PSCAD. Unfortunately, studying restoration of large power systems using such detailed models are computationally prohibitive. This paper proposes a hybrid simulation framework for power system restoration, which can represent a significant portion of the model in a phasor framework and co-simulate that with a detailed model of a smaller portion containing VSC-HVDC. To that end, a software called ETRANPLUS is used to interface the phasor model in PSSE software with the detailed model in EMTDC/PSCAD. © 2016 IEEE.
Katti K.S.,NDSU |
Katti D.R.,NDSU |
Molla M.S.,NDSU |
Poromechanics 2017 - Proceedings of the 6th Biot Conference on Poromechanics | Year: 2017
Tissue engineering scaffolds are very promising technologies in regenerative medicine for replacement of many hard and soft tissues. This methodology consists of seeding patient's cells onto porous mesh like structures called scaffolds that are made of degradable and biocompatible synthetic and biological materials. The scaffolds themselves have two-tiered interconnected porosities; one forming the overall microstructure and the other being wall porosities of the membranes that form the microstructure. Transport of fluids and bio-molecular entities assisting in mineralization and tissue formation through interconnected porosities is vital for the regeneration of tissue. The specific hierarchical porosities of scaffolds enable biomineralization and growth of a bone-mimetic environment. In this study, we demonstrated that when osteotropic cancer cells such as prostate and breast cancer are seeded on these scaffolds, they form tumoroids that mimic in vivo like early stage of cancer cell colonization at the metastatic bone site. We demonstrate the use of nanoindentation technique to evaluate mechanical properties of live cancer cells that may be used to describe disease progression in the future. We also demonstrate use of finite element methods to develop robust cancer cell models. These studies suggest the use of mechanics-based approaches that may be used in future to evaluate biochemical behaviors of cancer progression. © ASCE.
Shan T.,Xi'an Jiaotong University |
Ma Q.,Xi'an Jiaotong University |
Zhang D.,Xi'an Jiaotong University |
Guo K.,Xi'an Jiaotong University |
And 3 more authors.
European Journal of Pharmacology | Year: 2011
The stimulation of β2-adrenoceptor, which is a major mediator for chronic stress-induced cancers, has been implicated in the progression in the number of cancer cells, including pancreatic cancer, which remains one of the most aggressive and lethal diseases worldwide. Whether β-adrenoceptor antagonists potentiate gemcitabine, a standard first-line treatment for advanced pancreatic cancer that offers only modest benefit due to acquired chemoresistance, has not been elucidated. Thus, we studied the antiproliferative and apoptotic effects and the underlying mechanisms of gemcitabine combined with the β2-adrenoceptor blocker ICI 118551 (1-[2,3-(dihydro-7-methyl-1H- iden-4-yl)oxy]-3-[(1-methylethyl)amino]-2-butanol), in human pancreatic cancer BxPC-3 and MIA PaCa-2 cells. Results show that ICI 118551 significantly synergized the antiproliferative and pro-apoptotic effects induced by gemcitabine in both BxPC-3 and MIA PaCa-2 cells (P < 0.05 combination vs. control or gemcitabine alone). When cells were treated with the combination of gemcitabine and ICI 118551, NF-κB activation was blocked; the expression of Bax protein was substantially increased; and Bcl-2 protein was downregulated. Taken together, the data suggest that ICI 118551 potentiates the antiproliferative effects of gemcitabine by inducing apoptosis in pancreatic cancer cells. Our study implies that this combination may be an effective therapeutic strategy for pancreatic cancer. © 2011 Elsevier B.V. All rights reserved.
Xu J.,Xi'an Jiaotong University |
Li W.,Xi'an Jiaotong University |
Ma J.,Xi'an Jiaotong University |
Liu J.,Xi'an Jiaotong University |
And 4 more authors.
Current Medicinal Chemistry | Year: 2013
Various epidemiological studies have demonstrated that vitamin D may play important roles in the pathogenesis and progression of cancer. Vitamin D is one of the most pivotal nutraceuticals whose active metabolite, calcitriol (1,25-dihydroxyvitamin D3), possesses anti-proliferative, pro-apoptotic, and pro-differentiating capabilities. Accumulating evidence indicates that the potential benefits of using vitamin D in cancer are not only anti-cancer cell proliferation which is linked with its anti-inflammatory effects, including the suppression of prostaglandin metabolism and inhibition of NF-κB signaling, but also suppressing tumor metastasis and angiogenesis. Here, we present a systematic summary of the effects of vitamin D in the chemoprevention and chemotherapy of cancer, especially anti-metastatic and anti-angiogenic actions. © 2013 Bentham Science Publishers.
Li W.,Xi'an Jiaotong University |
Ma Q.,Xi'an Jiaotong University |
Liu J.,Xi'an Jiaotong University |
Han L.,Xi'an Jiaotong University |
And 5 more authors.
Frontiers in Bioscience | Year: 2012
As a vital step in the progression of cancer, metastasis poses the largest problem in cancer treatment and is the main cause of death of cancer patients. In pancreatic cancer, almost 80% of patients have locally deteriorated or metastatic disease and thus are not appropriate for resection at the time of diagnosis. Due to the high rate of incidence and mortality, it is crucial to study the molecular mechanisms of metastasis to clarify therapeutic targets to hinder the spread of cancer. Diabetes mellitus has long been considered a potential risk factor for pancreatic cancer. In this review, we comprehensively describe the role of hyperglycemia in governing critical steps of the metastatic process. In particular, we focus on the hyperglycemia-dependent aspects of the Epithelial- Mesenchymal Transition (EMT) and vascular dysfunction. Furthermore, we discuss how hyperglycemia-related production of reactive oxygen species (ROS) may play an important role in these two processes. A deep understanding of metastasis mechanisms will identify novel targets for therapeutic intervention.
Gagneja K.K.,NDSU |
2012 Federated Conference on Computer Science and Information Systems, FedCSIS 2012 | Year: 2012
Once sensors detect an event they always have to route the data to base station where the data is processed. Since sensors usually have concerns regarding coverage, energy, processing power and memory, etc achieving Quality of Service is hard in sensor networks. Therefore to deal with such issues of sensors and to maximize the Quality of Service, initially the two tiers Heterogeneous Sensor Networks approach is used to route the data. Second, the sensors are partitioned into clusters to increase the network coverage and to reduce transportation costs and energy utilization. Voronoi clustering and Tabu search meta-heuristics have been used for making such clusters. An Improved Tree Routing technique is applied to two-tier Heterogeneous Sensor Networks to route the data through cluster heads. This approach largely increases the performance of sensor networks. Through simulation results, we show that the Voronoi-Tabu based clustering technique when added to Improved Tree Routing has better Quality of Service than Directed Diffusion and Low Energy Adaptive Clustering Hierarchy routing protocols. Furthermore, empirical evaluations show that Voronoi-Tabu based clustering increases the throughput of the network, in addition to decreasing the energy utilization and network delays. © 2012 Polish Info Processing Socit.
Mc Phee K.E.,NDSU |
Inglis D.A.,Mount Vernon Northwestern Washington Research and Extension Center |
Gundersen B.,Mount Vernon Northwestern Washington Research and Extension Center |
Coyne C.J.,U.S. Department of Agriculture
Plant Breeding | Year: 2012
With 3 figures and 4 tables Fusarium oxysporum f.sp. pisi (Fop) exists in pea production regions worldwide and causes a vascular wilt resulting in significant crop losses. Four races of Fop have been identified, and resistance to each was reportedly conferred by an individual single dominant gene. Fnw confers resistance to Fop race 2, which can be a serious pathogen for both green and dry pea production in the Pacific Northwest region of the United States. The objectives of this research were to (i) place Fnw on the Pisum genetic map, (ii) detect additional genetic factors associated with resistance to race 2 and (iii) identify closely linked markers for use in pea breeding A recombinant inbred line (RIL) population of 187 F 7-derived lines from the cross 'Shawnee'/'Bohatyr' was developed by single-seed decent. All 187 RILs, the parents and one set of race 2 pea differential entries were inoculated with Fop race 2 under controlled conditions in three experiments, each with two or three replications per entry. Disease reactions were recorded as percentage diseased plants 10-14days postinoculation or at regular intervals through flowering or early pod fill. Data for progressive wilting over time, typical of Fop race 2, were used to calculate area under disease progress curve (AUDPC) values. Data for percentage diseased plants placed the putative single gene Fnw on Pisum sativum linkage group IV, with LOD scores ranging from 40.0 to 65.6 and minor loci on LG III (LOD 3.97 and 4.60). AUDPC values allowed for the detection of additional QTL on linkage group III with LOD scores of 3.97 and 4.60. The presence of recombinants in the population indicated that complementary genes were contributed by each parent, both of which showed intermediate reaction to Fop race 2. Results of this research provide a basis for marker-assisted selection of the major Fnw loci in both green and dry pea breeding programmes, but additional research is necessary to fully characterize the complementary gene action governing resistance of the two minor loci identified. © 2012 Blackwell Verlag GmbH.
News Article | September 29, 2016
Salt pollution is one of the most serious and persistent environmental problems worldwide – not the least because once it gets into the soil, it's extremely difficult to get out. Now a team of scientists at North Dakota State University (NDSU) has come up with a way to chemically coax the salt out of soil to form crystalline "blooms" that can be harvested like so many saline cauliflowers. Salt pollution in soil can take many forms. It can come from the highly saline brine used in fracking operations, road salting to melt snow, estuary flooding, or the cumulative effect of irrigation using brackish water. But according to NDSU, once salt gets into soil it can stay there for decades or centuries. Meanwhile, the land becomes useless for cultivation and susceptible to serious erosion. The problem is that conventional methods of handling salt-contaminated soils are often time consuming, complicated, slow, or not very useful. Some, for example, require the complete removal of the soil, which is expensive and only shifts the problem, or trying to flood the salt out, which wastes water and often merely drives the salt into the groundwater to percolate back up again. The biggest hurdle is that as salt water evaporates, the salt crystallizes and forms a solid crust in the soil pores, which effectively seals and protects the salt below from extraction. Looking for a way to overcome this, the NDSU team led by Aaron Daigh came across a chemical called ferric hexacyanoferrate, also known as Prussian Blue, which was being used by conservationists to protect historic sites that had been contaminated by road salt. What Daigh's team saw was that the ferric hexacyanoferrate caused the dissolved salts to crystallize out of the soil to form blooms that were high in water content on the soil surface. These blooms could then be easily shoveled up and removed. When the chemical was tested under laboratory conditions, the team found that over a seven day period it was able to remove 27 to 57 percent of the salt depending on the type of soil – promising a quick and simple decontamination method. According to Daigh, the technique still requires field testing and there is a concern about toxicity because ferric hexacyanoferrate releases free-cyanides as it decomposes. However, he went on to say that the breakdown is very slow, taking decades to centuries, which is enough time for microorganisms to consume any toxins that may arise. In addition, Daigh says that ferric hexacyanoferrate is only one chemical that could produce salt blooms, so future research will consist of seeking alternatives as well as how much and how often to apply it. Source:
News Article | December 4, 2015
North Dakota State University has its Center for Nanoscale Science and Engineering, due to a lack of funding. Operations ceased as of Sept. 30 — most employees found work elsewhere on the NDSU campus, while others found jobs in private industries. However, the center will continue to host research projects, and the cleanroom will be used in at least four classes, according to a published interview with Kelly Rusch, NDSU vice president for research and creative activity. According to Valley News, former North Dakota Senator is puzzled as to why the school closed the center, after he helped them secure over $140 million dollars in federal funding for CNSE between 2002 and 2010. The school has retorted that the center is not entirely closed. Dorgan has called the closure “a major loss of a great opportunity for NDSU.” Controlled Environments published a case study of the facility back in 2005. Read more: The 14,500 sq. ft. features 8,000 sq. ft. of service chase, and 4,100 sq. ft. of Class 10,000 and 2,300 sq. ft. of Class 100 cleanrooms for microsensors and nanotechnology research, plus traditional semiconductor processes. The center utilizes the cleanrooms for electronic miniaturization research and fabrication. The cleanrooms contain photolithography, wet chemistry and thin film deposition technology. The facility was founded in 2002, and it was used to develop coatings for Navy ships and ground sensors that were deployed in Iraq, in addition to other projects. But funding started decreasing for the center in 2011, after — are funds given by Congress for projects, programs, or grants where the purported congressional direction (whether in statutory text, report language, or other communication) circumvents otherwise applicable merit-based or competitive allocation processes, or specifies the location or recipient, or otherwise curtails the ability of the executive branch to manage its statutory and constitutional responsibilities pertaining to the funds allocation process. The center had to apply for small competitive grants after that, but it was not enough. The research group was posting 10 to 12 articles per year at its peak, and now it’s down to about six or seven. New hires ceased in 2012, and workers were laid off. Without proper funding and workers to operate the machinery, the lab equipment may grow stagnant from lack of use, and there isn’t enough money to buy new tools. North Dakota State University was one of the institutions who, in April of this year, received part of a $3.8 million grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture . NDSU’s share was $149,714. The school also received a portion of the National Science Foundation’s $81 million for its . This announcement, from September 2015, partners NDSU with the University of Minnesota Twin Cities.