Linking Theory of Disruptive Technology with Nuclear Security: UAS as an Emerging and Disruptive Technology

Technology used in nuclear security allows for many practical applications for securing material while simultaneously providing malicious opportunities for adversaries to potentially steal or misuse the material. Fixed sites and various modes of transport for nuclear and other radioactive material all can benefit from the use of new technology in mitigating against these threats. One emerging technology in nuclear security that is rapidly growing is the use of unmanned aerial systems (UAS). UASs provide a different dimension of security compared to methods that are traditionally used because of the added aerial characteristics of these devices. These devices offer new detection, delay, and response measures as operations are conducted using an aerial method rather than more traditional ground methods. Because of the increased popularity, availability, and capabilities of UAS technology, these tools are shifting trends in technology and how it is applied to nuclear security. The theory of disruptive innovation as it pertains to nuclear security is introduced as a guideline for assessing UAS technology. Additionally, regulation gaps relating to use of UAS technology in fixed site and transport security will be addressed. UAS technology is creating security incidents at nuclear sites and a new method of assessing this threat is needed to help determine the overall impact this technology is having in nuclear security and assist in distributing resources. A combination of a new dimension of use, increasing trends and security incidents, and lack of regulations shows signs that UAS is becoming a disruptive technology used in the nuclear security field

PROBING BIOMECHANICAL PROPERTIES OF SINGLE MOLECULE SYSTEMS USING OPTICAL TWEEZERS

Single molecule techniques have provided novel mechanistic insights on biological processes such as protein folding, transcription, and motor protein movement. Using single molecule methods, the distribution of individual molecular behavior is directly measured, which cannot be obtained using conventional bulk approaches. In this study, custom-built optical tweezers with sub-pN force resolution were used to probe the dynamic behavior of DNA:cationic carrier complex. Two histidine-lysine (HK) based polymers (H3K4b vs H3KG4b) were used to compare their condensation behaviors at the single molecular level. The difference between the two HK polymers at the single molecule level may have a significant implication as to why H3KG4b shows much higher gene delivery efficiency than H3K4b. The optical tweezers were also used to probe the unfolding processes of a fragment of F1 RNA. This can be used to characterize secondary structures in RNA, such as hairpins and pseudoknots

Molecular Characterization Of Membrane Proteins Of Schistosoma Mansoni

Schistosomiasis is one of the most prevalent human diseases and is caused by the long-term survival of parasitic blood flukes. Membrane constituents at the surface of these parasites play a major role in parasite metabolism and elaborate sophisticated mechanisms for evasion of the host immune response. Despite this fact, little is known about the molecular properties or functions of individual membrane proteins. This study provides information regarding two polypeptides associated with the apical plasma membrane (APM) of Schistosoma mansoni.;An in vitro system for studying protein phosphorylation in the isolated APM was developed and the protein substrates of endogenous protein kinase activity were described. A 24 kilodalton (kDa) phosphoprotein was characterized in detail. Analysis of the structure of this polypeptide by lectin affinity chromatography, endoglycosidase digestion and phase separation in Triton X-114 demonstrated that the 24 kDa molecule was an integral membrane protein with N-linked oligosaccharides. In addition, the 24 kDa phosphoprotein was shown to be a major APM immunogen by immunoprecipitation with anti-APM antisera and with antibodies affinity purified from the 24 kDa region of preparative Western blots.;In order to isolate cDNA clones encoding APM polypeptides, comprehensive cDNA expression libraries were constructed in {dollar}\lambda{dollar} bacteriophage vectors and were screened with anti-APM antisera. Two cDNA clones were isolated and their nucleotide sequences determined. One cDNA was 141 base pairs in length and was shown to encode antigenic determinants shared with the 24 kDa phosphoprotein antigen. This cDNA was not full length since the homologous mRNA was approximately 800 residues in length. A possible open reading frame from this cDNA however, contained a signal for N-linked glycosylation. A second near full-length cDNA of 2621 base pairs was also cloned and sequenced. An open reading frame deduced from this cDNA predicted a protein of 702 amino acids with a molecular weight of 76 kDa. The deduced protein sequence was shown to be similar to the known sequences of vertebrate calpains.;This study provides the basis for a detailed structure/function analysis of the membrane-associated polypeptides encoded by the cloned cDNAs

The effect of auxins (IAA and 4-CL-IAA) on the redox activity and medium pH of Zea mays L. root segments

Indole-3-acetic acid (IAA) and 4-chloroindole-3-acetic acid (4-Cl- IAA) were tested at different concentrations and times for their capacity to change the redox activity and medium pH of maize root segments. The doseresponse surfaces (dose-response curves as a function of time) plotted for redox activity and changes in medium pH (expressed as ΔpH) had a similar shape for both auxins, but differed significantly at the optimal concentrations. With 4-Cl- IAA, the maximal values of redox activity and medium pH changes were observed at 10-10 M, which was a 100-fold lower concentration than with IAA. Correlations were observed between redox activity and medium pH changes at the optimal concentrations of both IAA and 4-Cl-IAA. The results are discussed herein, taking into account both the concentration of the auxins and the effects produced by them

Effect of K+ and Ca2+ on the indole-3-acetic acid-and fusicoccin-induced growth and membrane potential in maize coleoptile cells

The role of potassium (K+) and calcium (Ca2+) in the regulation of plant growth and development is complex and needs a diverse range of physiological studies. Both elements are essential for satisfactory crop production. Here, the effects of K+ and Ca2+ ions on endogenous growth and growth in the presence of either indole-3-acetic acid (IAA) or fusicoccin (FC) were studied in maize (Zea mays) coleoptiles. Membrane potentials of coleoptile parenchymal cells, incubated in media containing IAA, FC and different concentrations of K+ and Ca2+, were also determined. Growth experiments have shown that in the absence of K+ in the incubation medium, both endogenous and IAA- or FC-induced growth were significantly inhibited by 0.1 and 1 mM Ca2+, respectively, while in the presence of 1 mM K+ they were inhibited only by 1 mM Ca2+. At 10 mM K+, endogenous growth and growth induced by either IAA or FC did not depend on Ca2+ concentration. TEA-Cl, a potassium channel blocker, added 1 h before IAA or FC, caused a reduction of growth by 59 or 45 %, respectively. In contrast to TEA-Cl, verapamil, the Ca2+ channel blocker, did not affect IAA- and FC-induced growth. It was also found that in parenchymal cells of maize coleoptile segments, membrane potential (Em) was strongly affected by the medium K+, independently of Ca2+. However, lack of Ca2+ in the incubation medium significantly reduced the IAA- and FC-induced membrane potential hyperpolarization. TEA-Cl applied to the control medium in the same way as in growth experiments caused Em hyperpolarization synergistic with hyperpolarization produced by IAA or FC. Verapamil did not change either the Em of parenchymal cells incubated in the control medium or the IAA- and FC-induced membrane hyperpolarization. The data presented here have been discussed considering the role of K+ uptake channels in regulation of plant cell growth

Development of novel cellular model for affinity studies of histamine H(4) receptor ligands

The G protein-coupled histamine H4 receptor (H4R) is the last member of histamine receptors family discovered so far. Its expression pattern, together with postulated involvement in a wide variety of immunological and inflammatory processes make histamine H4 receptor an interesting target for drug development. Potential H4R ligands may provide an innovative therapies for different immuno-based diseases, including allergy, asthma, pruritus associated with allergy or autoimmune skin conditions, rheumatoid arthritis and pain. However, none of successfully developed selective and potent histamine H4 receptor ligands have been introduced to the market up to date. For that reason there is still a strong demand for pharmacological models to be used in studies on potent H4R ligands. In current work we present the development of novel mammalian cell line, stably expressing human histamine H4 receptor, with use of retroviral transduction approach. Obtained cell line was pharmacologically characterized in radioligand binding studies and its utility for affinity testing of potent receptor ligands was confirmed in comparative studies with the use of relevant insect cells expression model. Obtained results allow for statement that developed cellular model may be successfully employed in search for new compounds active at histamine H4 receptor