Sample records for tta

  1. Effect of starvation and refeeding on the hepatopancreas of whiteleg shrimp Penaeus vannamei (Boone) using computer-assisted image analysis.

    PubMed

    Cervellione, F; McGurk, C; Berger Eriksen, T; Van den Broeck, W

    2017-11-01

    Under normal farming conditions, shrimp can experience starvation periods attributable to disease outbreaks or adverse environmental conditions. Starvation leads to significant morphological changes in the hepatopancreas (HP), being the main organ for absorption and storage of nutrients. In the literature, limited research has described the effect on the HP of periods of starvation followed by refeeding and none in whiteleg shrimp (Penaeus vannamei) using computer-assisted image analysis (CAIA). This study describes the effect of starvation and starvation followed by refeeding on the HP of whiteleg shrimp using CAIA. Visiopharm ® software was used to quantify the following morphological parameters, measured as ratio to the total tissue area (TLA): total lumen area (TLA:TTA), haemocytic infiltration area in the intertubular spaces (HIA:TTA), B-cell vacuole area (VBA:TTA), lipid droplet area within R cells (LDA:TTA) and F-cell area (FCA:TTA). Significant changes were measured for HIA:TTA and LDA:TTA during starvation (increase in HIA:TTA associated with decrease in LDA:TTA) and starvation followed by refeeding (decrease in HIA:TTA associated with increase in LDA:TTA). In the future, HIA:TTA and LDA:TTA have the potential to be used in a pre-emptive manner to monitor the health of the HP, facilitate early diagnosis of diseases and study the pathophysiology of the organ. © 2017 John Wiley & Sons Ltd.

  2. Comparison of autogenous cancellous bone grafting and extracorporeal shock wave therapy on osteotomy healing in the tibial tuberosity advancement procedure in dogs. Radiographic densitometric evaluation.

    PubMed

    Barnes, K; Lanz, O; Werre, S; Clapp, K; Gilley, R

    2015-01-01

    To compare optical values in the osteotomy gap created after a tibial tuberosity advancement (TTA) treated with autogenous cancellous bone graft, extracorporeal shock wave therapy, a combination of autogenous cancellous bone graft and extracorporeal shock wave therapy, and absence of both autogenous cancellous bone graft and extracorporeal shock wave therapy using densitometry. Dogs that were presented for surgical repair of a cranial cruciate ligament rupture were randomly assigned to one of four groups: TTA with autogenous cancellous bone graft (TTA-G), TTA with autogenous cancellous bone graft and extracorporeal shock wave therapy (TTA-GS), TTA with extracorporeal shock wave therapy (TTA-S), and TTA with no additional therapy (TTA-O). Mediolateral radiographs at zero, four and eight weeks after surgery were evaluated to compare healing of the osteotomy gap via densitometry. An analysis of variance was used to compare the densitometric values between groups. At four weeks after surgery, a significant difference in osteotomy gap density was noted between TTA-GS (8.4 millimetres of aluminium equivalent [mmAleq]) and TTA-S (6.1 mmAleq), and between TTA-GS (8.4 mmAleq) and TTA-O (6.4 mmAleq). There were no significant differences noted between any groups at the eight week re-evaluation. There were no significant differences in the osteotomy gap density at eight weeks after surgery regardless of the treatment modality used. The combination of autogenous cancellous bone graft and extracorporeal shock wave therapy may lead to increased radiographic density of the osteotomy gap in the first four weeks after surgery. Densitometry using an aluminium step wedge is a feasible method for comparison of bone density after TTA in dogs.

  3. How Do Vision and Hearing Impact Pedestrian Time-to-Arrival Judgments?

    PubMed Central

    Roper, JulieAnne M.; Hassan, Shirin E.

    2014-01-01

    Purpose To determine how accurate normally-sighted male and female pedestrians were at making time-to-arrival (TTA) judgments of approaching vehicles when using just their hearing or both their hearing and vision. Methods Ten male and 14 female subjects with confirmed normal vision and hearing estimated the TTA of approaching vehicles along an unsignalized street under two sensory conditions: (i) using both habitual vision and hearing; and (ii) using habitual hearing only. All subjects estimated how long the approaching vehicle would take to reach them (ie the TTA). The actual TTA of vehicles was also measured using custom made sensors. The error in TTA judgments for each subject under each sensory condition was calculated as the difference between the actual and estimated TTA. A secondary timing experiment was also conducted to adjust each subject’s TTA judgments for their “internal metronome”. Results Error in TTA judgments changed significantly as a function of both the actual TTA (p<0.0001) and sensory condition (p<0.0001). While no main effect for gender was found (p=0.19), the way the TTA judgments varied within each sensory condition for each gender was different (p<0.0001). Females tended to be as accurate under either condition (p≥0.01) with the exception of TTA judgments made when the actual TTA was two seconds or less and eight seconds or longer, during which the vision and hearing condition was more accurate (p≤0.002). Males made more accurate TTA judgments under the hearing only condition for actual TTA values five seconds or less (p<0.0001), after which there were no significant differences between the two conditions (p≥0.01). Conclusions Our data suggests that males and females use visual and auditory information differently when making TTA judgments. While the sensory condition did not affect the females’ accuracy in judgments, males initially tended to be more accurate when using their hearing only. PMID:24509543

  4. Effects of nandrolone decanoate on time to consolidation of bone defects resulting from osteotomy for tibial tuberosity advancement.

    PubMed

    Marques, Danilo R C; Marques, Danilo; Ibanez, Jose F; Freitas, Itallo B; Hespanha, Ana C; Monteiro, Juliana F; Eggert, Mayara; Becker, Amanda

    2017-09-12

    Experimental study. The aim of this study was to evaluate the effect of nandrolone decanoate (ND) on the time taken for bone consolidation in dogs undergoing tibial tuberosity advancement surgery (TTA). Seventeen dogs that underwent TTA surgery were randomly divided into two groups: group C (TTA; 9 stifles), and group TTA+ND (TTA and systemic administration of ND; 8 stifles). Three observers (two radiologists and an orthopaedic surgeon), assessed bone consolidation by visual inspection of serial radiographs at intervals of 21 days following surgery. There were no differences in median weight and age between groups, nor between the medians of the variables right and left stifle. Only weight and age values were normally distributed. The other variables, right and left stifle and time to consolidation, showed non-normal distribution. Meniscal injury was present in all animals in group C and all animals in group TTA+ND. There was a significant difference between time to consolidation in groups C and TTA+ND (p <0.05). One animal in the group TTA+ND showed increased libido. Kappa agreement among observers on radiographs was 0.87. Administration of ND reduces time to bone consolidation in dogs undergoing TTA.

  5. Triplet-triplet annihilation in highly efficient fluorescent organic light-emitting diodes: current state and future outlook.

    PubMed

    Kondakov, Denis Y

    2015-06-28

    Studies of delayed electroluminescence in highly efficient fluorescent organic light-emitting diodes (OLEDs) of many dissimilar architectures indicate that the triplet-triplet annihilation (TTA) significantly increases yield of excited singlet states-emitting molecules in this type of device thereby contributes substantially to their efficiency. Towards the end of the 2000s, the essential role of TTA in realizing highly efficient fluorescent devices was widely recognized. Analysis of a diverse set of fluorescent OLEDs shows that high efficiencies are often cor-related to TTA extents. It is therefore likely that it is the long-term empirical optimization of OLED efficiencies that has resulted in fortuitous emergence of TTA as a large and ubiquitous contributor to efficiency. TTA contributions as high as 20-30% are common in the state-of-the-art OLEDs, and even become dominant in special cases, where TTA is shown to substantially exceed the spin-statistical limit. The fundamental features of OLED efficiency enhancement via TTA-molecular structure-dependent contributions, current density-dependent intensities in practical devices and frequently observed antagonistic relationships between TTA extent and OLED lifetime-came to be understood over the course of the next few years. More recently, however, there was much less reported progress with respect to all-important quantitative details of the TTA mechanism. It should be emphasized that, to this day and despite the decades of work on improving blue phosphorescent OLEDs as well as the recent advent of thermally activated delayed fluorescence OLEDs, the majority of practical blue OLEDs still rely on TTA. Considering such practical importance of fluorescent blue OLEDs, the design of blue OLED-compatible materials capable of substantially exceeding the spin-statistical limit in TTA, elimination of the antagonistic relationship between TTA-related efficiency gains and lifetime losses, and designing devices with an extended range of current densities producing near-maximum TTA electroluminescence are the areas where future improvements would be most beneficial. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  6. Europium (III) Organic Complexes in Porous Boron Nitride Microfibers: Efficient Hybrid Luminescent Material

    NASA Astrophysics Data System (ADS)

    Lin, Jing; Feng, Congcong; He, Xin; Wang, Weijia; Fang, Yi; Liu, Zhenya; Li, Jie; Tang, Chengchun; Huang, Yang

    2016-09-01

    We report the design and synthesis of a novel kind of organic-inorganic hybrid material via the incorporation of europium (III) β-diketonate complexes (Eu(TTA)3, TTA = 2-thenoyltrifluoroacetone) into one-dimensional (1D) porous boron nitride (BN) microfibers. The developed Eu(TTA)3@BN hybrid composites with typical 1D fibrous morphology exhibit bright visible red-light emission on UV illumination. The confinement of Eu(TTA)3 within pores of BN microfibers not only decreases the aggregation-caused quenching in solid Eu(TTA)3, but also improves their thermal stabilities. Moreover, The strong interactions between Eu(TTA)3 and porous BN matrix result in an interesting energy transfer process from BN host to TTA ligand and TTA ligand to Eu3+ ions, leading to the remarkable increase of red emission. The synthetic approach should be a very promising strategy which can be easily expanded to other hybrid luminescent materials based on porous BN.

  7. Europium (III) Organic Complexes in Porous Boron Nitride Microfibers: Efficient Hybrid Luminescent Material

    PubMed Central

    Lin, Jing; Feng, Congcong; He, Xin; Wang, Weijia; Fang, Yi; Liu, Zhenya; Li, Jie; Tang, Chengchun; Huang, Yang

    2016-01-01

    We report the design and synthesis of a novel kind of organic-inorganic hybrid material via the incorporation of europium (III) β-diketonate complexes (Eu(TTA)3, TTA = 2-thenoyltrifluoroacetone) into one-dimensional (1D) porous boron nitride (BN) microfibers. The developed Eu(TTA)3@BN hybrid composites with typical 1D fibrous morphology exhibit bright visible red-light emission on UV illumination. The confinement of Eu(TTA)3 within pores of BN microfibers not only decreases the aggregation-caused quenching in solid Eu(TTA)3, but also improves their thermal stabilities. Moreover, The strong interactions between Eu(TTA)3 and porous BN matrix result in an interesting energy transfer process from BN host to TTA ligand and TTA ligand to Eu3+ ions, leading to the remarkable increase of red emission. The synthetic approach should be a very promising strategy which can be easily expanded to other hybrid luminescent materials based on porous BN. PMID:27687246

  8. Time to Appendectomy and Risk of Complicated Appendicitis and Adverse Outcomes in Children.

    PubMed

    Serres, Stephanie K; Cameron, Danielle B; Glass, Charity C; Graham, Dionne A; Zurakowski, David; Karki, Mahima; Anandalwar, Seema P; Rangel, Shawn J

    2017-08-01

    Management of appendicitis as an urgent rather than emergency procedure has become an increasingly common practice in children. Controversy remains as to whether this practice is associated with increased risk of complicated appendicitis and adverse events. To examine the association between time to appendectomy (TTA) and risk of complicated appendicitis and postoperative complications. In this retrospective cohort study using the Pediatric National Surgical Quality Improvement Program appendectomy pilot database, 2429 children younger than 18 years who underwent appendectomy within 24 hours of presentation at 23 children's hospitals from January 1, 2013, through December 31, 2014, were studied. The main exposure was TTA, defined as the time from emergency department presentation to appendectomy. Patients were further categorized into early and late TTA groups based on whether their TTA was shorter or longer than their hospital's median TTA. Exposures were defined in this manner to compare rates of complicated appendicitis within a time frame sensitive to each hospital's existing infrastructure and diagnostic practices. The primary outcome was complicated appendicitis documented at operation. The association between treatment delay and complicated appendicitis was examined across all hospitals by using TTA as a continuous variable and at the level of individual hospitals by using TTA as a categorical variable comparing outcomes between late and early TTA groups. Secondary outcomes included length of stay (LOS) and postoperative complications (incisional and organ space infections, percutaneous drainage procedures, unplanned reoperation, and hospital revisits). Of the 6767 patients who met the inclusion criteria, 2429 were included in the analysis (median age, 10 years; interquartile range, 8-13 years; 1467 [60.4%] male). Median hospital TTA was 7.4 hours (range, 5.0-19.2 hours), and 574 patients (23.6%) were diagnosed with complicated appendicitis (range, 5.2%-51.1% across hospitals). In multivariable analyses, increasing TTA was not associated with risk of complicated appendicitis (odds ratio per 1-hour increase in TTA, 0.99; 95% CI, 0.97-1.02). The odds ratios of complicated appendicitis for late vs early TTA across hospitals ranged from 0.39 to 9.63, and only 1 of the 23 hospitals had a statistically significant increase in their late TTA group (odds ratio, 9.63; 95% CI, 1.08-86.17; P = .03). Increasing TTA was associated with longer LOS (increase in mean LOS for each additional hour of TTA, 0.06 days; 95% CI, 0.03-0.08 days; P < .001) but was not associated with increased risk of any of the other secondary outcomes. Delay of appendectomy within 24 hours of presentation was not associated with increased risk of complicated appendicitis or adverse outcomes. These results support the premise that appendectomy can be safely performed as an urgent rather than emergency procedure.

  9. Computerized pediatric telephone triage and advice programs at children's hospitals: operating and financial characteristics.

    PubMed

    Melzer, S M; Poole, S R

    1999-08-01

    To describe the operating characteristics, financial performance, and perceived value of computerized children's hospital-based telephone triage and advice (TTA) programs. A written survey of all 32 children's hospital-based TTA programs in the United States that used the same proprietary pediatric TTA software product for at least 6 months. The expense, revenues, and perceived value of children's hospital-based TTA programs. Of 30 programs (94%) responding, 27 (90%) were eligible for the study and reported on their experience with nearly 1.3 million TTA calls over a 12-month period. Programs provided pediatric TTA services for 1560 physicians, serving an average of 82 physicians (range, 10-340 physicians) and answering 38880 calls (range, 8500-140000 calls) annually. The mean call duration was 11.3 minutes and the estimated mean total expense per call was $12.45. Of programs charging fees for TTA services, 16 (59%) used a per-call fee and 7 (26%) used a monthly service fee. All respondents indicated that fees did not cover all associated costs. Telephone triage and advice programs, when examined on a stand-alone basis, were all operating with annual deficits (mean, $447000; median, $325000; range, $74000-$1.3 million), supported by the sponsoring children's hospitals and their companion programs. Using a 3-point Likert scale, the TTA program managers rated the value of the TTA program very highly as a mechanism for marketing to physicians (2.85) and increasing physician (2.92) and patient (2.80) satisfaction. Children's hospital-based TTA programs operate at substantial financial deficits. Ongoing support of these programs may derive from the perception that they are a valuable mechanism for marketing and increase patient and physician satisfaction. Children's hospitals should develop strategies to ensure the long-term financial viability of TTA programs or they may have to discontinue these services.

  10. Restraint status improves the predictive value of motor vehicle crash criteria for pediatric trauma team activation.

    PubMed

    Bozeman, Andrew P; Dassinger, Melvin S; Recicar, John F; Smith, Samuel D; Rettiganti, Mallikarjuna R; Nick, Todd G; Maxson, Robert T

    2012-12-01

    Most trauma centers incorporate mechanistic criteria (MC) into their algorithm for trauma team activation (TTA). We hypothesized that characteristics of the crash are less reliable than restraint status in predicting significant injury and the need for TTA. We identified 271 patients (age, <15 y) admitted with a diagnosis of motor vehicle crash. Mechanistic criteria and restraint status of each patient were recorded. Both MC and MC plus restraint status were evaluated as separate measures for appropriately predicting TTA based on treatment outcomes and injury scores. Improper restraint alone predicted a need for TTA with an odds ratios of 2.69 (P = .002). MC plus improper restraint predicted the need for TTA with an odds ratio of 2.52 (P = .002). In contrast, the odds ratio when using MC alone was 1.65 (P = .16). When the 5 MC were evaluated individually as predictive of TTA, ejection, death of occupant, and intrusion more than 18 inches were statistically significant. Improper restraint is an independent predictor of necessitating TTA in this single-institution study. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Time-to-Antibiotic Administration as a Quality of Care Measure in Children with Febrile Neutropenia: A Survey of Pediatric Oncology Centers

    PubMed Central

    McCavit, Timothy L.; Winick, Naomi

    2011-01-01

    Time-to-antibiotic administration (TTA) has been suggested as a quality-of-care (QOC) measure for pediatric oncology patients with febrile neutropenia (FN). Unknown, however, is to what extent pediatric oncology centers utilize TTA. Therefore, we designed and administered an electronic survey (68% response rate) of programs in the Children's Oncology Group to assess TTA utilization. Nearly half of respondents track TTA. Most reported using a benchmark of less than 60 minutes from arrival. TTA is a commonly used QOC measure for pediatric FN despite an absence of studies establishing its validity and a lack of data supporting its impact on outcomes of FN. PMID:21509930

  12. Using Genetic Buffering Relationships Identified in Fission Yeast To Elucidate the Molecular Pathology of Tuberous Sclerosis

    DTIC Science & Technology

    2016-07-01

    5’-aat tat ttt ata tgg aat gag caa gta tgt ttt atc ata att gac cag ttc att tca agg acc ttc aaa aat ata cct acg aat tcg agc tcg ttt aaa c-3’), or...oTsc13 (5’-tta aga gtt cag att tgc ttt atg tgg tta ttc tgc tga agg tcc taa ttt att gac gtt gaa aaa taa agg cca cat agc gga tcc ccg ggt taa tta a-3...and oTsc14 (5’-ata aaa aaa att aat taa tga tgg caa ggc aca atc gta atc aat ctt tta att tag gac ttt tta tat gcc ctt atg gcg aat tcg agc tcg ttt aaa c

  13. pH-sensitive fluorescent sensors based on europium(III) complexes.

    PubMed

    Zhang, Xiaolin; Jiao, Yang; Jing, Xu; Wu, Hongmei; He, Guangjie; Duan, Chunying

    2011-03-21

    New europium(III) complexes Eu(TTA)(2)-DSQ and Eu(TTA)(3)-DR1 were designed and synthesized as new fluorescent pH probes (where HDSQ = 5-(dimethylamino)-N-(4-(2-((8-hydroxyquinolin-2-yl)methylene)hydrazinecarbonyl)phenyl)naphthalene-1-sulfonamide, DR1 = N(1)-(4-(dimethylamino)benzylidene)-N(2)-(rhodamine-6G) lactamethylene-diamine and TTA = thiophentrifluoroacetone). Eu(TTA)(2)-DSQ exhibited high sensitivity in monitoring pH changes in neutral aqueous solution with negligible background fluorescence. Eu(TTA)(3)-DR1 comprised a green light emitting Rhodamine 6G fluorophore and a Eu(III) moiety as the origin of red light. These pH-sensitive emitter components have pK(a) values of 5.0 and 7.2 respectively, and exhibit isolated protonated steps within one molecule. Luminescence titrations demonstrate that Eu(TTA)(3)-DR1 was able to detect pH values at both near neutral pH and acidic pH ranges, and was also able to detect pH in both cultured cells and in vivo.

  14. Red light emitting nano-PVP fibers that hybrid with Ag@SiO2@Eu(tta)3phen-NPs by electrostatic spinning method

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaolin; Tang, Jianguo; Li, Haidong; Wang, Yao; Wang, Xinzhi; Wang, Yanxin; Huang, Linjun; Belfiore, Laurence A.

    2018-04-01

    This work demonstrated red light emitting nano-PVP fibers that incorporated with novel three-layer nanostructure of Ag@SiO2@Eu(tta)3phen nanoparticles (Ag@SiO2@Eu(tta)3phen-NPs), and the hybrid nano-PVP fibers were fabricated via a remarkably simple electrostatic spinning method. For Ag@SiO2@Eu(tta)3phen-NPs, the thickness of SiO2 is optimized to obtain the maximum luminescent intensity, as results, the optimized thickness of SiO2 is 20 nm. And the corresponding luminescent intensity (612 nm) of the Ag@SiO2@Eu(tta)3phen-NPs is enhanced up to 10 times compared with the pure Eu(tta)3phen complex, which indicates that with 20 nm SiO2 thickness, the localized surface plasmon resonance (LSPR) effect of Ag@SiO2 exhibits highest performance for enhancing luminescence. Moreover, the luminescent PVP fibers emit bright red light under the fluorescence microscope, which definitely confirms that the microenvironment provided by PVP polymer is absolutely suitable for the fluorescent composites.

  15. Advancing Understanding of the +4 Metal Extractant Thenoyltrifluoroacetonate (TTA-); Synthesis and Structure of MIVTTA4 (MIV = Zr, Hf, Ce, Th, U, Np, Pu) and MIII(TTA)4- (MIII = Ce, Nd, Sm, Yb).

    PubMed

    Cary, Samantha K; Livshits, Maksim; Cross, Justin N; Ferrier, Maryline G; Mocko, Veronika; Stein, Benjamin W; Kozimor, Stosh A; Scott, Brian L; Rack, Jeffrey J

    2018-04-02

    Thenoyltrifluoroacetone (HTTA)-based extractions represent popular methods for separating microscopic amounts of transuranic actinides (i.e., Np and Pu) from macroscopic actinide matrixes (e.g. bulk uranium). It is well-established that this procedure enables +4 actinides to be selectively removed from +3, + 5, and +6 f-elements. However, even highly skilled and well-trained researchers find this process complicated and (at times) unpredictable. It is difficult to improve the HTTA extraction-or find alternatives-because little is understood about why this separation works. Even the identities of the extracted species are unknown. In addressing this knowledge gap, we report here advances in fundamental understanding of the HTTA-based extraction. This effort included comparatively evaluating HTTA complexation with +4 and +3 metals (M IV = Zr, Hf, Ce, Th, U, Np, and Pu vs M III = Ce, Nd, Sm, and Yb). We observed +4 metals formed neutral complexes of the general formula M IV (TTA) 4 . Meanwhile, +3 metals formed anionic M III (TTA) 4 - species. Characterization of these M(TTA) 4 x- ( x = 0, 1) compounds by UV-vis-NIR, IR, 1 H and 19 F NMR, single-crystal X-ray diffraction, and X-ray absorption spectroscopy (both near-edge and extended fine structure) was critical for determining that Np IV (TTA) 4 and Pu IV (TTA) 4 were the primary species extracted by HTTA. Furthermore, this information lays the foundation to begin developing and understanding of why the HTTA extraction works so well. The data suggest that the solubility differences between M IV (TTA) 4 and M III (TTA) 4 - are likely a major contributor to the selectivity of HTTA extractions for +4 cations over +3 metals. Moreover, these results will enable future studies focused on explaining HTTA extractions preference for +4 cations, which increases from Np IV to Pu IV , Hf IV , and Zr IV .

  16. Time-Tag Generation Script

    NASA Technical Reports Server (NTRS)

    Jackson, Dan E.

    2010-01-01

    Time-Tag Generation Script (TTaGS) is an application program, written in the AWK scripting language, for generating commands for aiming one Ku-band antenna and two S-band antennas for communicating with spacecraft. TTaGS saves between 2 and 4 person-hours per every 24 hours by automating the repetitious process of building between 150 and 180 antenna-control commands. TTaGS reads a text database of communication satellite schedules and a text database of satellite rise and set times and cross-references items in the two databases. It then compares the scheduled start and stop with the geometric rise and set to compute the times to execute antenna control commands. While so doing, TTaGS determines whether to generate commands for guidance, navigation, and control computers to tell them which satellites to track. To help prevent Ku-band irradiation of the Earth, TTaGS accepts input from the user about horizon tolerance and accordingly restricts activation and effects deactivation of the transmitter. TTaGS can be modified easily to enable tracking of additional satellites and for such other tasks as reading Sun-rise/set tables to generate commands to point the solar photovoltaic arrays of the International Space Station at the Sun.

  17. Advancing Understanding of the +4 Metal Extractant Thenoyltrifluoroacetonate (TTA –); Synthesis and Structure of M IVTTA 4 (M IV = Zr, Hf, Ce, Th, U, Np, Pu) and M III(TTA) 4 – (M III = Ce, Nd, Sm, Yb)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cary, Samantha K.; Livshits, Maksim; Cross, Justin N.

    Thenoyltrifluoroacetone (HTTA)-based extractions represent popular methods for separating microscopic amounts of transuranic actinides (i.e., Np and Pu) from macroscopic actinide matrixes (e.g. bulk uranium). It is well-established that this procedure enables +4 actinides to be selectively removed from +3, + 5, and +6 f-elements. However, even highly skilled and well-trained researchers find this process complicated and (at times) unpredictable. It is difficult to improve the HTTA extraction—or find alternatives—because little is understood about why this separation works. Even the identities of the extracted species are unknown. In addressing this knowledge gap, we report in this paper advances in fundamental understandingmore » of the HTTA-based extraction. This effort included comparatively evaluating HTTA complexation with +4 and +3 metals (M IV = Zr, Hf, Ce, Th, U, Np, and Pu vs M III = Ce, Nd, Sm, and Yb). We observed +4 metals formed neutral complexes of the general formula M IV(TTA) 4. Meanwhile, +3 metals formed anionic M III(TTA) 4 – species. Characterization of these M(TTA) 4 x– (x = 0, 1) compounds by UV–vis–NIR, IR, 1H and 19F NMR, single-crystal X-ray diffraction, and X-ray absorption spectroscopy (both near-edge and extended fine structure) was critical for determining that Np IV(TTA) 4 and Pu IV(TTA) 4 were the primary species extracted by HTTA. Furthermore, this information lays the foundation to begin developing and understanding of why the HTTA extraction works so well. The data suggest that the solubility differences between M IV(TTA) 4 and M III(TTA) 4 – are likely a major contributor to the selectivity of HTTA extractions for +4 cations over +3 metals. Finally and moreover, these results will enable future studies focused on explaining HTTA extractions preference for +4 cations, which increases from Np IV to Pu IV, Hf IV, and Zr IV.« less

  18. Advancing Understanding of the +4 Metal Extractant Thenoyltrifluoroacetonate (TTA –); Synthesis and Structure of M IVTTA 4 (M IV = Zr, Hf, Ce, Th, U, Np, Pu) and M III(TTA) 4 – (M III = Ce, Nd, Sm, Yb)

    DOE PAGES

    Cary, Samantha K.; Livshits, Maksim; Cross, Justin N.; ...

    2018-03-21

    Thenoyltrifluoroacetone (HTTA)-based extractions represent popular methods for separating microscopic amounts of transuranic actinides (i.e., Np and Pu) from macroscopic actinide matrixes (e.g. bulk uranium). It is well-established that this procedure enables +4 actinides to be selectively removed from +3, + 5, and +6 f-elements. However, even highly skilled and well-trained researchers find this process complicated and (at times) unpredictable. It is difficult to improve the HTTA extraction—or find alternatives—because little is understood about why this separation works. Even the identities of the extracted species are unknown. In addressing this knowledge gap, we report in this paper advances in fundamental understandingmore » of the HTTA-based extraction. This effort included comparatively evaluating HTTA complexation with +4 and +3 metals (M IV = Zr, Hf, Ce, Th, U, Np, and Pu vs M III = Ce, Nd, Sm, and Yb). We observed +4 metals formed neutral complexes of the general formula M IV(TTA) 4. Meanwhile, +3 metals formed anionic M III(TTA) 4 – species. Characterization of these M(TTA) 4 x– (x = 0, 1) compounds by UV–vis–NIR, IR, 1H and 19F NMR, single-crystal X-ray diffraction, and X-ray absorption spectroscopy (both near-edge and extended fine structure) was critical for determining that Np IV(TTA) 4 and Pu IV(TTA) 4 were the primary species extracted by HTTA. Furthermore, this information lays the foundation to begin developing and understanding of why the HTTA extraction works so well. The data suggest that the solubility differences between M IV(TTA) 4 and M III(TTA) 4 – are likely a major contributor to the selectivity of HTTA extractions for +4 cations over +3 metals. Finally and moreover, these results will enable future studies focused on explaining HTTA extractions preference for +4 cations, which increases from Np IV to Pu IV, Hf IV, and Zr IV.« less

  19. Analysis of the phosphorescent dye concentration dependence of triplet-triplet annihilation in organic host-guest systems

    NASA Astrophysics Data System (ADS)

    Zhang, L.; van Eersel, H.; Bobbert, P. A.; Coehoorn, R.

    2016-10-01

    Using a novel method for analyzing transient photoluminescence (PL) experiments, a microscopic description is obtained for the dye concentration dependence of triplet-triplet annihilation (TTA) in phosphorescent host-guest systems. It is demonstrated that the TTA-mechanism, which could be a single-step dominated process or a diffusion-mediated multi-step process, can be deduced for any given dye concentration from a recently proposed PL intensity analysis. A comparison with the results of kinetic Monte Carlo simulations provides the TTA-Förster radius and shows that the TTA enhancement due to triplet diffusion can be well described in a microscopic manner assuming Förster- or Dexter-type energy transfer.

  20. Triplet diffusion leads to triplet-triplet annihilation in organic phosphorescent emitters

    NASA Astrophysics Data System (ADS)

    Zhang, Yifan; Forrest, Stephen R.

    2013-12-01

    In organic materials, triplet-triplet annihilation (TTA) can be dominated by triplet diffusion or triplet-to-triplet energy transfer. Here, we discuss the diffusion and transfer dominated mechanisms in the context of photoluminescence (PL) transient measurements from thin films of archetype phosphorescent organic light emitters based on Ir and Pt complexes. We find that TTA in these emitters is controlled by diffusion due to a Dexter-type exchange interaction, suggesting triplet radiative decay and TTA are independent processes. Minimizing the PL and absorption spectral overlap in phosphorescent emitters can lead to a significantly decreased TTA rate, and thus suppressed efficiency roll-off in phosphorescent organic light emitting diodes at high brightness.

  1. Reducing the photo-bleaching effect of a new europium complex embedded in styrene butadiene copolymer

    NASA Astrophysics Data System (ADS)

    Jiménez, G. Lesly; Reyes-Rodríguez, J. L.; Padilla, Isela; Alarcón-Flores, G.; Falcony, C.

    2018-02-01

    A highly luminescent europium complex obtained with two different ligands, succinimide (SI) and 2-thenoyltrifluoroacetone (TTA) , was synthetized with different TTA concentrations. The photoluminescence (PL) emission from these materials corresponds to the characteristic inter-electronic energy level transitions of the Eu3+ ions. However, the excitation spectrum is strongly dependent on the presence of TTA, having an optimum response when 0.75 mmol of this compound is added to the EuL3(H2O)3 complex. The quantum yield obtained by these powders were around 72 % ± 1.7 % indicating an optimum sensitization of these complex. The EuL3 TTA complex with the best PL properties was embedded in a styrene butadiene copolymer (SBC) film, produced by the drop casting method, obtaining similar PL behavior at different concentrations, the highest intensity was observed at 1.2% (w/v) of EuL3 TTA complex and the quantum yield of these composite films was 60.5 % ± 2 % . These films were exposed to continuous UV irradiation and after 141 h no photo-bleaching effect was observed in contrast with the EuL3 TTA complex that exhibited a noticeable photoluminescence intensity degradation at much shorter exposure times. Both the Eu-complexes and the composite films were characterized by FT-IR, XRD, SEM and fluorescence spectroscopy.

  2. Blockade of T-type calcium channels prevents tonic-clonic seizures in a maximal electroshock seizure model.

    PubMed

    Sakkaki, Sophie; Gangarossa, Giuseppe; Lerat, Benoit; Françon, Dominique; Forichon, Luc; Chemin, Jean; Valjent, Emmanuel; Lerner-Natoli, Mireille; Lory, Philippe

    2016-02-01

    T-type (Cav3) calcium channels play important roles in neuronal excitability, both in normal and pathological activities of the brain. In particular, they contribute to hyper-excitability disorders such as epilepsy. Here we have characterized the anticonvulsant properties of TTA-A2, a selective T-type channel blocker, in mouse. Using the maximal electroshock seizure (MES) as a model of tonic-clonic generalized seizures, we report that mice treated with TTA-A2 (0.3 mg/kg and higher doses) were significantly protected against tonic seizures. Although no major change in Local Field Potential (LFP) pattern was observed during the MES seizure, analysis of the late post-ictal period revealed a significant increase in the delta frequency power in animals treated with TTA-A2. Similar results were obtained for Cav3.1-/- mice, which were less prone to develop tonic seizures in the MES test, but not for Cav3.2-/- mice. Analysis of extracellular signal-regulated kinase 1/2 (ERK) phosphorylation and c-Fos expression revealed a rapid and elevated neuronal activation in the hippocampus following MES clonic seizures, which was unchanged in TTA-A2 treated animals. Overall, our data indicate that TTA-A2 is a potent anticonvulsant and that the Cav3.1 isoform plays a prominent role in mediating TTA-A2 tonic seizure protection. Copyright © 2015. Published by Elsevier Ltd.

  3. Differential Neurotoxicity Related to Tetracycline Transactivator and TDP-43 Expression in Conditional TDP-43 Mouse Model of Frontotemporal Lobar Degeneration.

    PubMed

    Kukreja, L; Shahidehpour, R; Kim, G; Keegan, J; Sadleir, K R; Russell, T; Csernansky, J; Mesulam, M; Vassar, R J; Wang, L; Dong, H; Geula, C

    2018-05-28

    Frontotemporal lobar degeneration (FTLD) is among the most prevalent dementias of early-onset. Pathologically, FTLD presents with tauopathy or TAR DNA-binding protein 43 (TDP-43) proteinopathy. A biallelic mouse model of FTLD was produced on a mix FVB/129SVE background overexpressing wild-type human TDP-43 (hTDP-43) employing tetracycline transactivator (tTA), a system widely used in mouse models of neurological disorders. tTA activates hTDP-43 which is placed downstream of the tetracycline response element (TRE). The original study on this transgenic mouse found hippocampal degeneration following hTDP-43 expression, but did not account for independent effects of tTA protein. Here, we initially analyzed the neurotoxic effects of tTA in post-weaning age mice of either sex using immunostaining and area measurements of select brain regions. We observed tTA-dependent toxicity selectively in the hippocampus affecting the dentate gyrus significantly more than CA fields, whereas hTDP-43-dependent toxicity in bigenic mice occurred in most other cortical regions. Atrophy was associated with inflammation, activation of caspase-3 and loss of neurons. The atrophy associated with tTA expression was rescuable by tetracycline analog, doxycycline in the diet. MRI studies corroborated the patterns of atrophy. tTA-induced degeneration was strain-dependent and was rescued by moving the transgene onto a congenic C57BL/6 background. Despite significant hippocampal atrophy, behavioral tests in bigenic mice revealed no hippocampally mediated memory impairment. Significant atrophy in most cortical areas due solely to TDP-43 expression indicates that this mouse model remains useful for providing critical insight into co-occurrence of TDP-43 pathology, neurodegeneration and behavioral deficits in FTLD. SIGNIFICANCE STATEMENT The tTA expression system has been widely used in mice to model neurological disorders. The technique allows investigators to reversibly turn on or off disease causing genes. Here, we report on a mouse model that overexpresses human TDP-43 using tTA and attempt to recapitulate features of TDP-43 pathology present in human FTLD. The tTA expression system is problematic, resulting in dramatic degeneration of the hippocampus. Thus, our study adds a note of caution for the use of the tTA system. However, since FTLD is primarily characterized by cortical degeneration and our mouse model shows significant atrophy in most cortical areas due to human TDP-43 overexpression, our animal model remains useful for providing critical insight on this human disease. Copyright © 2018 the authors.

  4. Organosilylated complex [Eu(TTA)3(Bpy-Si)]: a bifunctional moiety for the engeneering of luminescent silica-based nanoparticles for bioimaging.

    PubMed

    Duarte, Adriana P; Mauline, Léïla; Gressier, Marie; Dexpert-Ghys, Jeannette; Roques, Christine; Caiut, José Maurício A; Deffune, Elenice; Maia, Danielle C G; Carlos, Iracilda Z; Ferreira, Antonio A P; Ribeiro, Sidney J L; Menu, Marie-Joëlle

    2013-05-14

    A new highly luminescent europium complex with the formula [Eu(TTA)3(Bpy-Si)], where TTA stands for the thenoyltrifluoroacetone, (C4H3S)COCH2COCF3, chelating ligand and Bpy-Si, Bpy-CH2NH(CH2)3Si(OEt)3, is an organosilyldipyridine ligand displaying a triethoxysilyl group as a grafting function has been synthesized and fully characterized. This bifunctional complex has been grafted onto the surface of dense silica nanoparticles (NPs) and on mesoporous silica microparticles as well. The covalent bonding of [Eu(TTA)3(Bpy-Si)] inside uniform Stöber silica nanoparticles was also achieved. The general methodology proposed could be applied to any silica matrix, allowed high grafting ratios that overcome chelate release and the tendency to agglomerate. Luminescent silica-based nanoparticles SiO2-[Eu(TTA)3(Bpy-Si)], with a diameter of 28 ± 2 nm, were successfully tested as a luminescent labels for the imaging of Pseudomonas aeruginosa biofilms. They were also functionalized by a specific monoclonal antibody and subsequently employed for the selective imaging of Escherichia coli bacteria.

  5. 3D Long-Range Triplet Migration in a Water-Stable Metal-Organic Framework for Upconversion-Based Ultralow-Power in Vivo Imaging.

    PubMed

    Park, Jihye; Xu, Ming; Li, Fuyou; Zhou, Hong-Cai

    2018-04-25

    Triplet-triplet annihilation upconversion (TTA-UC) has gained increasing attention because it allows for harvesting of low-energy photons in the solar spectrum with high efficiency in relevant applications including solar cells and bioimaging. However, the utilization of conventional TTA-UC systems for low-power bioapplications is significantly hampered by their general incompatibility and low efficiency in aqueous media. Herein we report a metal-organic framework (MOF) as a biocompatible nanoplatform for TTA-UC to realize low-power in vivo imaging. Our MOF consists of a porphyrinic sensitizer in an anthracene-based Zr-MOF as a TTA-UC platform. In particular, closely aligned chromophores in the MOF facilitate a long-range 3D triplet diffusion of 1.6 μm allowing efficient energy migration in water. The tunable ratio between sensitizer and annihilator by our synthetic method also allows an optimization of the system for maximized TTA-UC efficiency in water at a very low excitation power density. Consequently, the low-power imaging of lymph node in a live mouse was successfully demonstrated with an excellent signal-to-noise ratio (SNR > 30 at 5 mW cm -2 ).

  6. Synthesis, characterization, and luminescent properties of Eu3+ dipyridophenazine functionalized complexes for potential bioimaging applications

    NASA Astrophysics Data System (ADS)

    Beasley, Jeremy

    Luminescent properties of lanthanide complexes possess unique characteristics that make them good candidates for possible bioimaging agents and have inspired research initiatives to further explore these materials. However, the toxicity of these metals limits their applications as in-vivo bioimaging agents. One solution that eliminates the toxic effects is to encase these lanthanide complexes in silica. This project was designed to probe the variation in the fluorescence properties of a highly luminescent europium (III) complex, utilizing a fluorinated â-diketonate ligand (thenoyltrifluoroacetone (tta)), upon the substitution of the solvent molecules by various functionalized dipyrido[3,2-a:2',3'-c]phenazine (DPPZ) ligands. A method for covalently attaching, or occluding complexes in silica nanoparticles were also included in the project design. The structure and properties of the functionalized DPPZ ligands and their respective complexes were determined by FT-IR, 1H-NMR, UV-Vis, and fluorescence spectroscopy techniques. UV excitation of the complexes resulted in red luminescence (~ 614 nm) characteristic of trivalent europium ions. The differences in luminescence properties of the complexes are rationalized in terms of the electronic features of the different functionalized DPPZ ligands. The higher overall quantum yield of the un-functionalized DPPZ complex, Eu(tta)3DPPZ (Q.Y.= 7.68 +/- 0.06 %), and the low overall quantum yield observed for Eu(tta)3DPPZ-COOEt (Q.Y.= 1.08 +/- 0.05%), Eu(tta) 3DPPZ-Si (Q.Y.= 0.65+/- 0.04%), Eu(tta)3DPPZ-COOH (Q.Y.= 0.61+/- 0.07 %), Eu(tta)3DPPZ-CH3 (Q.Y.= 0.59+/-0.02 %) are rationalized in terms of how electron donating or withdrawing groups affect their respective ligand-to-metal energy transfer efficiencies. Eu(tta) 3DPPZ was the only complex to show enhanced luminescent properties capable of potential applications in biomedical imaging.

  7. A Tracking Analyst for large 3D spatiotemporal data from multiple sources (case study: Tracking volcanic eruptions in the atmosphere)

    NASA Astrophysics Data System (ADS)

    Gad, Mohamed A.; Elshehaly, Mai H.; Gračanin, Denis; Elmongui, Hicham G.

    2018-02-01

    This research presents a novel Trajectory-based Tracking Analyst (TTA) that can track and link spatiotemporally variable data from multiple sources. The proposed technique uses trajectory information to determine the positions of time-enabled and spatially variable scatter data at any given time through a combination of along trajectory adjustment and spatial interpolation. The TTA is applied in this research to track large spatiotemporal data of volcanic eruptions (acquired using multi-sensors) in the unsteady flow field of the atmosphere. The TTA enables tracking injections into the atmospheric flow field, the reconstruction of the spatiotemporally variable data at any desired time, and the spatiotemporal join of attribute data from multiple sources. In addition, we were able to create a smooth animation of the volcanic ash plume at interactive rates. The initial results indicate that the TTA can be applied to a wide range of multiple-source data.

  8. Structure and Properties of Melt-spun Bio-based Polyamide/Eu(TTA)3Phen Composite fibers

    NASA Astrophysics Data System (ADS)

    Li, Yunye; Lou, Pengfei; Jia, Qingxiu

    2018-02-01

    In this paper, the bio-based polyamide (PA ) was melt polymerized from four bio-based monomers. Composites of the bio-based PA and europium complex Eu(TTA)3Phen were prepared through solution mixing using N, N-Dimethylformamide (DMF) and formic acid as the mixed solvent, and then composite fibers were obtained by melt spinning method. The structure and properties of the melt-spun composite fibers were characterized by FTIR and SEM. The results indicated that the Eu(TTA)3Phen complex, with the average diameter below 300 nm, was homogeneously dispersed in the PA matrix. FTIR spectra indicated that the coordination bond between carbonyl of BDIS and Eu(TTA)3Phen complex formed, which was also confirmed by the mechanical properties. The initial modulus and breaking strength of these fibers can arrived at 2.5GPa and 0.3GPa, respectively.

  9. Magnetic Field Effects on Triplet-Triplet Annihilation in Solutions: Modulation of Visible/NIR Luminescence.

    PubMed

    Mani, Tomoyasu; Vinogradov, Sergei A

    2013-08-06

    Photon upconversion based on sensitized triplet-triplet annihilation (TTA) presents interest for such areas as photovoltaics and imaging. Usually energy upconversion is observed as p -type delayed fluorescence from molecules whose triplet states are populated via energy transfer from a suitable triplet donor, followed by TTA. Magnetic field effects (MFE) on delayed fluorescence in molecular crystals are well known; however, there exist only a few examples of MFE on TTA in solutions, and all of them are limited to UV-emitting materials. Here we present MFE on TTA-mediated visible and near infrared (NIR) emission, sensitized by far-red absorbing metalloporphyrins in solutions at room temperature. In addition to visible delayed fluorescence from annihilator, we also observed NIR emission from the sensitizer, occurring as a result of triplet-triplet energy transfer back from annihilator, termed "delayed phosphorescence". This emission also exhibits MFE, but opposite in sign to the annihilator fluorescence.

  10. Locomotor adaptability in persons with unilateral transtibial amputation.

    PubMed

    Darter, Benjamin J; Bastian, Amy J; Wolf, Erik J; Husson, Elizabeth M; Labrecque, Bethany A; Hendershot, Brad D

    2017-01-01

    Locomotor adaptation enables walkers to modify strategies when faced with challenging walking conditions. While a variety of neurological injuries can impair locomotor adaptability, the effect of a lower extremity amputation on adaptability is poorly understood. Determine if locomotor adaptability is impaired in persons with unilateral transtibial amputation (TTA). The locomotor adaptability of 10 persons with a TTA and 8 persons without an amputation was tested while walking on a split-belt treadmill with the parallel belts running at the same (tied) or different (split) speeds. In the split condition, participants walked for 15 minutes with the respective belts moving at 0.5 m/s and 1.5 m/s. Temporal spatial symmetry measures were used to evaluate reactive accommodations to the perturbation, and the adaptive/de-adaptive response. Persons with TTA and the reference group of persons without amputation both demonstrated highly symmetric walking at baseline. During the split adaptation and tied post-adaptation walking both groups responded with the expected reactive accommodations. Likewise, adaptive and de-adaptive responses were observed. The magnitude and rate of change in the adaptive and de-adaptive responses were similar for persons with TTA and those without an amputation. Furthermore, adaptability was no different based on belt assignment for the prosthetic limb during split adaptation walking. Reactive changes and locomotor adaptation in response to a challenging and novel walking condition were similar in persons with TTA to those without an amputation. Results suggest persons with TTA have the capacity to modify locomotor strategies to meet the demands of most walking conditions despite challenges imposed by an amputation and use of a prosthetic limb.

  11. Effect of Förster-mediated triplet-polaron quenching and triplet-triplet annihilation on the efficiency roll-off of organic light-emitting diodes

    NASA Astrophysics Data System (ADS)

    van Eersel, H.; Bobbert, P. A.; Janssen, R. A. J.; Coehoorn, R.

    2016-04-01

    We report the results of a systematic study of the interplay of triplet-polaron quenching (TPQ) and triplet-triplet annihilation (TTA) on the efficiency roll-off of organic light-emitting diodes (OLEDs) with increasing current density. First, we focus on OLEDs based on the green phosphorescent emitter tris[2-phenylpyridine]iridium(III) (Ir(ppy)3) and the red phosphorescent dye platinum octaethylporphyrin. It is found that the experimental data can be reproduced using kinetic Monte Carlo (kMC) simulations within which TPQ and TTA are due to a nearest-neighbor (NN) interaction, or due to a more long-range Förster-type process. Furthermore, we find a subtle interplay between TPQ and TTA: decreasing the contribution of one process can increase the contribution of the other process, so that the roll-off is not significantly reduced. Furthermore, we find that just analyzing the shape of the roll-off is insufficient for determining the relative role of TPQ and TTA. Subsequently, we investigate the wider validity of this picture using kMC simulations for idealized but realistic symmetric OLEDs, with an emissive layer containing a small concentration of phosphorescent dye molecules in a matrix material. Whereas for NN-interactions the roll-off can be reduced when the dye molecules act as shallow hole and electron traps, we find that such an approach becomes counterproductive for long-range TTA and TPQ. Developing well-founded OLED design rules will thus require that more quantitative information is available on the rate and detailed mechanism of the TPQ and TTA processes.

  12. Long Term Functional Outcome of Tibial Tuberosity Advancement vs. Tibial Plateau Leveling Osteotomy and Extracapsular Repair in a Heterogeneous Population of Dogs.

    PubMed

    Krotscheck, Ursula; Nelson, Samantha A; Todhunter, Rory J; Stone, Marisa; Zhang, Zhiwu

    2016-02-01

    To determine a long term function of tibial tuberosity advancement (TTA) for treatment of ruptured cranial cruciate ligament (CCL) in dogs, and to compare this to the long term function of previously reported tibial plateau leveling osteotomy (TPLO), extracapsular reconstruction (ECR), and a population of normal dogs. Prospective clinical trial. Dogs with unilateral ruptured CCL treated with TTA (n = 14), TPLO (n = 15), and ECR (n = 23), and normal adult dogs (control, n = 80). Force plate gait analysis was performed at 1 time point for the normal control group and preoperatively, and at 2 and 8 weeks and 6 and 12 months postoperatively for the treatment groups. Using serial force plates, symmetry indices (SI) were calculated between the operated and unoperated pelvic limbs for peak vertical force (PVF), contact time (CT), and vertical impulse (VI). Ground reaction forces (GRF) of the treatment and control group were compared using a general linear model. Walk SI for dogs with TTA were not significantly different from the control group at 12 months postoperatively. At the trot, neither TTA nor ECR achieved normal GRF. SI of the TPLO group were not different from the normal control group by 6-12 months postoperatively. At the walk, TTA achieves normal function by 12 months; however, at the trot TTA is indistinguishable from ECR. TPLO resulted in operated limb function that was similar to the control population by 6-12 months postoperatively at the walk and the trot. © Copyright 2016 by The American College of Veterinary Surgeons.

  13. Red-light-controllable liquid-crystal soft actuators via low-power excited upconversion based on triplet-triplet annihilation.

    PubMed

    Jiang, Zhen; Xu, Ming; Li, Fuyou; Yu, Yanlei

    2013-11-06

    A red-light-controllable soft actuator has been achieved, driven by low-power excited triplet-triplet annihilation-based upconversion luminescence (TTA-UCL). First, a red-to-blue TTA-based upconversion system with a high absolute quantum yield of 9.3 ± 0.5% was prepared by utilizing platinum(II) tetraphenyltetrabenzoporphyrin (PtTPBP) as the sensitizer and 9,10-bis(diphenylphosphoryl)anthracene (BDPPA) as the annihilator. In order to be employed as a highly effective phototrigger of photodeformable cross-linked liquid-crystal polymers (CLCPs), the PtTPBP&BDPPA system was incorporated into a rubbery polyurethane film and then assembled with an azotolane-containing CLCP film. The generating assembly film bent toward the light source when irradiated with a 635 nm laser at low power density of 200 mW cm(-2) because the TTA-UCL was effectively utilized by the azotolane moieties in the CLCP film, inducing their trans-cis photoisomerization and an alignment change of the mesogens via an emission-reabsorption process. It is the first example of a soft actuator in which the TTA-UCL is trapped and utilized to create photomechanical effect. Such advantages of using this novel red-light-controllable soft actuator in potential biological applications have also been demonstrated as negligible thermal effect and its excellent penetration ability into tissues. This work not only provides a novel photomanipulated soft actuation material system based on the TTA-UCL technology but also introduces a new technological application of the TTA-based upconversion system in photonic devices.

  14. Cardiac overexpression of Mammalian enabled (Mena) exacerbates heart failure in mice

    PubMed Central

    Belmonte, Stephen L.; Ram, Rashmi; Mickelsen, Deanne M.; Gertler, Frank B.

    2013-01-01

    Mammalian enabled (Mena) is a key regulator of cytoskeletal actin dynamics, which has been implicated in heart failure (HF). We have previously demonstrated that cardiac Mena deletion produced cardiac dysfunction with conduction abnormalities and hypertrophy. Moreover, elevated Mena expression correlates with HF in human and animal models, yet the precise role of Mena in cardiac pathophysiology is unclear. In these studies, we evaluated mice with cardiac myocyte-specific Mena overexpression (TTA/TgTetMena) comparable to that observed in cardiac pathology. We found that the hearts of TTA/TgTetMena mice were functionally and morphologically comparable to wild-type littermates, except for mildly increased heart mass in the transgenic mice. Interestingly, TTA/TgTetMena mice were particularly susceptible to cardiac injury, as these animals experienced pronounced decreases in ejection fraction and fractional shortening as well as heart dilatation and hypertrophy after transverse aortic constriction (TAC). By “turning off” Mena overexpression in TTA/TgTetMena mice either immediately prior to or immediately after TAC surgery, we discovered that normalizing Mena levels eliminated cardiac hypertrophy in TTA/TgTetMena animals but did not preclude post-TAC cardiac functional deterioration. These findings indicate that hearts with increased levels of Mena fare worse when subjected to cardiac injury and suggest that Mena contributes to HF pathophysiology. PMID:23832697

  15. Cardiac overexpression of Mammalian enabled (Mena) exacerbates heart failure in mice.

    PubMed

    Belmonte, Stephen L; Ram, Rashmi; Mickelsen, Deanne M; Gertler, Frank B; Blaxall, Burns C

    2013-09-15

    Mammalian enabled (Mena) is a key regulator of cytoskeletal actin dynamics, which has been implicated in heart failure (HF). We have previously demonstrated that cardiac Mena deletion produced cardiac dysfunction with conduction abnormalities and hypertrophy. Moreover, elevated Mena expression correlates with HF in human and animal models, yet the precise role of Mena in cardiac pathophysiology is unclear. In these studies, we evaluated mice with cardiac myocyte-specific Mena overexpression (TTA/TgTetMena) comparable to that observed in cardiac pathology. We found that the hearts of TTA/TgTetMena mice were functionally and morphologically comparable to wild-type littermates, except for mildly increased heart mass in the transgenic mice. Interestingly, TTA/TgTetMena mice were particularly susceptible to cardiac injury, as these animals experienced pronounced decreases in ejection fraction and fractional shortening as well as heart dilatation and hypertrophy after transverse aortic constriction (TAC). By "turning off" Mena overexpression in TTA/TgTetMena mice either immediately prior to or immediately after TAC surgery, we discovered that normalizing Mena levels eliminated cardiac hypertrophy in TTA/TgTetMena animals but did not preclude post-TAC cardiac functional deterioration. These findings indicate that hearts with increased levels of Mena fare worse when subjected to cardiac injury and suggest that Mena contributes to HF pathophysiology.

  16. Effect of Förster-mediated triplet-polaron quenching and triplet-triplet annihilation on the efficiency roll-off of organic light-emitting diodes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eersel, H. van; Bobbert, P. A.; Janssen, R. A. J.

    2016-04-28

    We report the results of a systematic study of the interplay of triplet-polaron quenching (TPQ) and triplet-triplet annihilation (TTA) on the efficiency roll-off of organic light-emitting diodes (OLEDs) with increasing current density. First, we focus on OLEDs based on the green phosphorescent emitter tris[2-phenylpyridine]iridium(III) (Ir(ppy){sub 3}) and the red phosphorescent dye platinum octaethylporphyrin. It is found that the experimental data can be reproduced using kinetic Monte Carlo (kMC) simulations within which TPQ and TTA are due to a nearest-neighbor (NN) interaction, or due to a more long-range Förster-type process. Furthermore, we find a subtle interplay between TPQ and TTA: decreasingmore » the contribution of one process can increase the contribution of the other process, so that the roll-off is not significantly reduced. Furthermore, we find that just analyzing the shape of the roll-off is insufficient for determining the relative role of TPQ and TTA. Subsequently, we investigate the wider validity of this picture using kMC simulations for idealized but realistic symmetric OLEDs, with an emissive layer containing a small concentration of phosphorescent dye molecules in a matrix material. Whereas for NN-interactions the roll-off can be reduced when the dye molecules act as shallow hole and electron traps, we find that such an approach becomes counterproductive for long-range TTA and TPQ. Developing well-founded OLED design rules will thus require that more quantitative information is available on the rate and detailed mechanism of the TPQ and TTA processes.« less

  17. Retrospective Analysis of Dose Titration and Serum Testosterone Level Assessments in Patients Treated With Topical Testosterone.

    PubMed

    Muram, David; Kaltenboeck, Anna; Boytsov, Natalie; Hayes-Larson, Eleanor; Ivanova, Jasmina; Birnbaum, Howard G; Swindle, Ralph

    2015-11-01

    Patterns of care following topical testosterone agent (TTA) initiation are poorly understood. This study aimed to characterize care following TTA initiation and compare results between patients with and without a serum testosterone (T) assay within 30 days before and including TTA initiation. Adult men (N=4,146) initiating TTAs from January 1, 2011, to March 31, 2012, were identified from a commercially insured database. Patients were included if they initiated at recommended starting dose (RSD) and had ≥12 and ≥6 months of continuous eligibility preinitiation (baseline) and postinitiation (study period), respectively. Patients were stratified by preinitiation T assay. Maintenance dose attainment month was determined using unadjusted generalized estimating equations regression to compare dose relative to RSD month by month. Outcomes included maintenance dose attainment month, time to stopping of index TTA refills or a claim for nonindex testosterone replacement therapy (TRT), and proportion of patients with study period T assay or diagnosis of hypogonadism (HG) or another low testosterone condition, and were compared using chi-square and Wilcoxon rank-sum tests for categorical and continuous variables, respectively. Maintenance dose was attained in Month 4 postinitiation, at 115.2% of RSD. Approximately 46% of patients had a preinitiation T assay; these men were more likely to receive a diagnosis of HG or another low testosterone condition, to have a follow-up T assay, to continue treatment by filling a nonindex TRT, and less likely to stop refilling treatment with their index TTA. Differences in care following TTA initiation suggest that preinitiation T assays (i.e., guideline-based care) may be helpful in ensuring treatment benefits. © The Author(s) 2014.

  18. Developing tTA Transgenic Rats for Inducible and Reversible Gene Expression

    PubMed Central

    Zhou, Hongxia; Huang, Cao; Yang, Min; Landel, Carlisle P; Xia, Pedro Yuxing; Liu, Yong-Jian; Xia, Xu Gang

    2009-01-01

    To develop transgenic lines for conditional expression of desired genes in rats, we generated several lines of the transgenic rats carrying the tetracycline-controlled transactivator (tTA) gene. Using a vigorous, ubiquitous promoter to drive the tTA transgene, we obtained widespread expression of tTA in various tissues. Expression of tTA was sufficient to strongly activate its reporter gene, but was below the toxicity threshold. We examined the dynamics of Doxycycline (Dox)-regulated gene expression in transgenic rats. In the two transmittable lines, tTA-mediated activation of the reporter gene was fully subject to regulation by Dox. Dox dose-dependently suppressed tTA-activated gene expression. The washout time for the effects of Dox was dose-dependent. We tested a complex regime of Dox administration to determine the optimal effectiveness and washout duration. Dox was administered at a high dose (500 μg/ml in drinking water) for two days to reach the effective concentration, and then was given at a low dose (20 μg/ml) to maintain effectiveness. This regimen of Dox administration can achieve a quick switch between ON and OFF statuses of tTA-activated gene expression. In addition, administration of Dox to pregnant rats fully suppressed postnatal tTA-activated gene expression in their offspring. Sufficient levels of Dox are present in mother's milk to produce maximal efficacy in nursing neonates. Administration of Dox to pregnant or nursing rats can provide a continual suppression of tTA-dependent gene expression during embryonic and postnatal development. The tTA transgenic rat allows for inducible and reversible gene expression in the rat; this important tool will be valuable in the development of genetic rat models of human diseases. PMID:19214245

  19. Lac-L-TTA, a novel lactose-based amino acid-sugar conjugate for anti-metastatic applications.

    PubMed

    Roviello, Giovanni N; Iannitti, Roberta; Palumbo, Rosanna; Simonyan, Hayarpi; Vicidomini, Caterina; Roviello, Valentina

    2017-08-01

    Here we describe the synthesis, chromatographic purification, MS and NMR characterization of a new lactosyl-derivative, i.e. a lactosyl thiophenyl-substituted triazolyl-thione L-alanine (Lac-L-TTA). This amino acid-sugar conjugate was prepared by solution synthesis in analogy to the natural fructosyl-amino acids. Furthermore, we investigated the inhibition of PC-3 prostate cancer cell colony formation by this lactose derivative in comparison with the less polar fructose-based derivative, Fru-L-TTA. This let us to compare the properties of the artificial derivative, object of the present work, with the monosaccharide-based counterpart and to obtain a preliminary information on the influence of polarity on such biological activity. A significantly higher anticancer effect of Lac-L-TTA with respect to the fructose analogue emerged from our study suggesting that the anti-metastatic potential of fructosyl-amino acids can be enhanced by increasing the polarity of the compounds, for example by introducing disaccharide moieties in place of fructose.

  20. Plasmon-Enhanced Sub-Bandgap Photocatalysis via Triplet-Triplet Annihilation Upconversion for Volatile Organic Compound Degradation.

    PubMed

    Kim, Hyoung-Il; Weon, Seunghyun; Kang, Homan; Hagstrom, Anna L; Kwon, Oh Seok; Lee, Yoon-Sik; Choi, Wonyong; Kim, Jae-Hong

    2016-10-18

    This study demonstrates the first reported photocatalytic decomposition of an indoor air pollutant, acetaldehyde, using low-energy, sub-bandgap photons harnessed through sensitized triplet-triplet annihilation (TTA) upconversion (UC). To utilize low-intensity noncoherent indoor light and maximize photocatalytic activity, we designed a plasmon-enhanced sub-bandgap photocatalyst device consisting of two main components: (1) TTA-UC rubbery polymer films containing broad-band plasmonic particles (Ag-SiO 2 ) to upconvert sub-bandgap photons, and (2) nanodiamond (ND)-loaded WO 3 as a visible-light photocatalyst composite. Effective decomposition of acetaldehyde was achieved using ND/WO 3 (E g = 2.8 eV) coupled with TTA-UC polymer films that emit blue photons (λ Em = 425 nm, 2.92 eV) upconverted from green photons (λ Ex = 532 nm, 2.33 eV), which are wasted in most environmental photocatalysis. The overall photocatalytic efficiency was amplified by the broad-band surface plasmon resonance of AgNP-SiO 2 particles incorporated into the TTA-UC films.

  1. Optical characterization of the new nanocomposite SBMA/Eu(TTA)3(Ph3PO)2

    NASA Astrophysics Data System (ADS)

    Bordian, Olga; Verlan, Victor; Culeac, Ion; Iovu, Mihail; Zubareva, Vera; Nistor, Iurie

    2015-02-01

    We describe a new nanocomposite material based on the copolymer of styrene with butyl methacrylate (1:1) (SBMA), and coordinating compound of Europium(III) Eu(TTA)3(Ph3PO)2. The SBMA/Eu(TTA)3(Ph3PO)2 nanocomposite was prepared by a simple technology and can be obtained in the form of optical fibers, thin films and planar waveguides on various substrates with large area. Experimental results on optical transmission and photoluminescence spectroscopy are presented. The nanocomposite exhibits a strong photoluminescence emission in the range 560-750 nm, with the main photoluminescence band at 613 nm.

  2. TTA codons in some genes prevent their expression in a class of developmental, antibiotic-negative, Streptomyces mutants.

    PubMed Central

    Leskiw, B K; Lawlor, E J; Fernandez-Abalos, J M; Chater, K F

    1991-01-01

    In Streptomyces coelicolor A3(2) and the related species Streptomyces lividans 66, aerial mycelium formation and antibiotic production are blocked by mutations in bldA, which specifies a tRNA(Leu)-like gene product which would recognize the UUA codon. Here we show that phenotypic expression of three disparate genes (carB, lacZ, and ampC) containing TTA codons depends strongly on bldA. Site-directed mutagenesis of carB, changing its two TTA codons to CTC (leucine) codons, resulted in bldA-independent expression; hence the bldA product is the principal tRNA for the UUA codon. Two other genes (hyg and aad) containing TTA codons show a medium-dependent reduction in phenotypic expression (hygromycin resistance and spectinomycin resistance, respectively) in bldA mutants. For hyg, evidence is presented that the UUA codon is probably being translated by a tRNA with an imperfectly matched anticodon, giving very low levels of gene product but relatively high resistance to hygromycin. It is proposed that TTA codons may be generally absent from genes expressed during vegetative growth and from the structural genes for differentiation and antibiotic production but present in some regulatory and resistance genes associated with the latter processes. The codon may therefore play a role in developmental regulation. Images PMID:1826053

  3. Major complications of tibial tuberosity advancement in 1613 dogs.

    PubMed

    Costa, Mario; Craig, Diane; Cambridge, Tony; Sebestyen, Peter; Su, Yuhua; Fahie, Maria A

    2017-05-01

    To report major postoperative complications in 1613 dogs with tibial tuberosity advancement (TTA). Retrospective case series. Dogs (n = 1613) with cranial cruciate ligament deficiency treated with TTA. Medical records of TTAs performed between December 2007-2013 were reviewed for age, sex, weight, contralateral stifle surgery, surgical approach, duration of preoperative lameness, presence of meniscal damage, concurrent patellar luxation and simultaneous bilateral TTA. Major postoperative complications were defined as surgical site infection (SSI) (superficial, deep, or organ/space), implant failure, fracture, patellar luxation, and meniscal tear. Major complications were recorded in 13.4% of cases. Superficial SSI (incisional irritation) was diagnosed in 6.9% cases, requiring only antimicrobial therapy. Other complications included postliminary medial meniscal tear (2% incidence), deep SSI (incisional dehiscence, 1.1%), implant failure (1%), patellar luxation (1.2%), fracture (0.9%), and organ/space SSI (septic arthritis, 0.4%). Dogs with normal menisci were less likely to develop postliminary meniscal tears if the medial meniscus was released at the time of TTA (P < .0001). No association was detected between recorded parameters and complications, although dogs >8 years old approached significance (P = .05) in terms of predisposition to major complications. Major complications after TTA are uncommon, even in dogs with concurrent patellar luxation or bilateral simultaneous procedures. In spite of its morbidity, medial meniscal release may prevent postliminary meniscal tears. © 2017 The American College of Veterinary Surgeons.

  4. NHSA Position Paper: The Design of a Head Start Training and Technical Assistance System.

    ERIC Educational Resources Information Center

    NHSA Journal, 1994

    1994-01-01

    This position paper examines the current Head Start training and technical assistance (TTA) system and proposes specific improvements. These include the creation of regional TTA offices, the use of satellite and interactive communications technology, and a reevaluation of the role of teaching centers, national training contracts, and Head Start…

  5. Increased hepatic mitochondrial FA oxidation reduces plasma and liver TG levels and is associated with regulation of UCPs and APOC-III in rats

    PubMed Central

    Lindquist, Carine; Bjørndal, Bodil; Rossmann, Christine Renate; Tusubira, Deusdedit; Svardal, Asbjørn; Røsland, Gro Vatne; Tronstad, Karl Johan; Hallström, Seth; Berge, Rolf Kristian

    2017-01-01

    Hepatic mitochondrial function, APOC-III, and LPL are potential targets for triglyceride (TG)-lowering drugs. After 3 weeks of dietary treatment with the compound 2-(tridec-12-yn-1-ylthio)acetic acid (1-triple TTA), the hepatic mitochondrial FA oxidation increased more than 5-fold in male Wistar rats. Gene expression analysis in liver showed significant downregulation of APOC-III and upregulation of LPL and the VLDL receptor. This led to lower hepatic (53%) and plasma (73%) TG levels. Concomitantly, liver-specific biomarkers related to mitochondrial biogenesis and function (mitochondrial DNA, citrate synthase activity, and cytochrome c and TFAM gene expression) were elevated. Interestingly, 1-triple TTA lowered plasma acetylcarnitine levels, whereas the concentration of β-hydroxybutyrate was increased. The hepatic energy state was reduced in 1-triple TTA-treated rats, as reflected by increased AMP/ATP and decreased ATP/ADP ratios, whereas the energy state remained unchanged in muscle and heart. The 1-triple TTA administration induced gene expression of uncoupling protein (UCP)2 and UCP3 in liver. In conclusion, the 1-triple TTA-mediated clearance of blood TG may result from lowered APOC-III production, increased hepatic LPL gene expression, mitochondrial FA oxidation, and (re)uptake of VLDL facilitating drainage of FAs to the liver for β-oxidation and production of ketone bodies as extrahepatic fuel. The possibility that UCP2 and UCP3 mediate a moderate degree of mitochondrial uncoupling should be considered. PMID:28473603

  6. Effect of tibial tuberosity advancement on femorotibial contact mechanics and stifle kinematics.

    PubMed

    Kim, Stanley E; Pozzi, Antonio; Banks, Scott A; Conrad, Bryan P; Lewis, Daniel D

    2009-01-01

    Objective- To evaluate the effects of tibial tuberosity advancement (TTA) on femorotibial contact mechanics and 3-dimensional kinematics in cranial cruciate ligament (CrCL)-deficient stifles of dogs. Study Design- In vitro biomechanical study. Animals- Unpaired pelvic limbs from 8 dogs, weighing 28-35 kg. Methods- Digital pressure sensors placed subjacent to the menisci were used to measure femorotibial contact force, contact area, peak and mean contact pressure, and peak pressure location with the limb under an axial load of 30% body weight and a stifle angle of 135 degrees . Three-dimensional static poses of the stifle were obtained using a Microscribe digitizing arm. Each specimen was tested under normal, CrCL-deficient, and TTA-treated conditions. Repeated measures analysis of variance with a Tukey post hoc test (P<.05) was used for statistical comparison. Results- Significant disturbances to all measured contact mechanic parameters were evident after CrCL transection, which corresponded to marked cranial tibial subluxation and internal tibial rotation in the CrCL-deficient stifle. No significant differences in any contact mechanic and kinematic parameters were detected between normal and TTA-treated stifles. Conclusion- TTA eliminates craniocaudal stifle instability during simulated weight-bearing and concurrently restores femorotibial contact mechanics to normal. Clinical Relevance- TTA may mitigate the progression of stifle osteoarthritis in dogs afflicted with CrCL insufficiency by eliminating cranial tibial thrust while preserving the normal orientation of the proximal tibial articulating surface.

  7. Promoter Variant-Dependent mRNA Expression of the MEF2A in Longissimus Dorsi Muscle in Cattle

    PubMed Central

    Starzyński, Rafał Radosław; Wicińska, Krystyna; Flisikowski, Krzysztof

    2012-01-01

    The myocyte enhancer factor 2A (MEF2A) gene encodes a member of the myocyte enhancer factor 2 (MEF2) protein family that is involved in vertebrate skeletal, cardiac, and smooth muscle development and differentiation during myogenesis. According to recent studies, MEF2 genes might be major regulators of postnatal skeletal muscle growth; thus, they are considered to be important, novel candidates for muscle development and body growth in farm animals. The aim of the present study was to search for polymorphisms in the bovine MEF2A gene and analyze their effect on the MEF2A mRNA expression level in the longissimus dorsi muscle of Polish Holstein-Fresian cattle. In total, 4094 bp of the whole coding sequence and the promoter region of MEF2A were re-sequenced in 30 animals, resulting in the detection of 6 novel variants as well as one previously reported SNP. Three linked mutations in the promoter region (-780T/G, g.-768T/G, and g.-222A/G) and only two genotypes were identified in two Polish breeds (TTA/TTA and TTA/GGG). Three SNPs in the coding region [g.1599G/A (421aa), g.1626G/A (429aa), and g.1641G/A (434aa)] appeared to be silent substitutions and segregated as two intragene haplotypes: GGG and AAA. Expression analysis showed that the mutations in the promoter region are highly associated with the MEF2A mRNA level in the longissimus dorsi muscle of bulls carrying two different genotypes. The higher MEF2A mRNA level was estimated in the muscle of bulls carrying the TTA/TTA (p<0.01) genotype as compared with those with TTA/GGG. The results obtained suggest that the nucleotide sequence mutation in MEF2A might be useful marker for body growth traits in cattle. PMID:22320864

  8. Endoscopic Endonasal Transsphenoidal Approach

    PubMed Central

    Cappabianca, Paolo; Alfieri, Alessandra; Colao, Annamaria; Ferone, Diego; Lombardi, Gaetano; de Divitiis, Enrico

    1999-01-01

    The outcome of endoscopic endonasal transsphenoidal surgery in 10 patients with pituitary adenomas was compared with that of traditional transnasal transsphenoidal approach (TTA) in 20 subjects. Among the 10 individuals subjected to “pure endoscopy,” 2 had a microadenoma, 1 an intrasellar macroadenoma, 4 had a macroadenoma with suprasellar expansion, 2 had a macroadenoma with supra-parasellar expansion, and 1 a residual tumor; 5 had acromegaly and 5 had a nonfunctioning adenoma (NFA). Among the patients subjected to TTA, 4 had a microadenoma, 2 had an intrasellar macroadenoma, 6 had a macroadenoma with suprasellar expansion, 4 had a macroadenoma with supra-parasellar expansion, and 4 had a residual tumor; 9 patients had acromegaly, 1 hyperprolactinemia, 1 Cushing's disease, and 9 a NFA. At the macroscopic evaluation, tumor removal was total (100%) after endoscopy in 9 patients and after TTA in 14 patients. Six months after surgery, magnetic resonance imaging (MRI) confirmed the total tumor removal in 21 of 23 patients (91.3%). Circulating growth hormone (GH) and insulin-like growth factor-I (IGF-I) significantly decreased 6 months after surgery in all 14 acromegalic patients: normalization of plasma IGF-I levels was obtained in 4 of 5 patients after the endoscopic procedure and in 4 of 9 patients after TTA. Before surgery, pituitary hormone deficiency was present in 14 out of 30 patients: pituitary function improved in 4 patients, remaining unchanged in the other 10 patients. Visual field defects were present before surgery in 4 patients, and improved in all. Early surgical results in the group of 10 patients who underwent endoscopic pituitary tumor removal were at least equivalent to those of standard TTA, with excellent postoperative course. Postsurgical hospital stay was significantly shorter (3.1 ± 0.4 vs. 6.2 ± 0.3 days, p < 0.001) after endoscopy as compared to TTA. ImagesFigure 1Figure 2 PMID:17171126

  9. T-type calcium channel antagonism decreases motivation for nicotine and blocks nicotine- and cue-induced reinstatement for a response previously reinforced with nicotine.

    PubMed

    Uslaner, Jason M; Vardigan, Joshua D; Drott, Jason M; Uebele, Victor N; Renger, John J; Lee, Ariel; Li, Zhaoxia; Lê, A D; Hutson, Pete H

    2010-10-15

    Recent evidence suggests an involvement of T-type calcium channels in the effects of drugs of abuse. We examined the influence of the novel, potent, and selective T-type calcium channel antagonist [2-(4-cyclopropylphenyl)-N-((1R)-1-{5-[2,2,2-trifluoroethyl]oxo}pyridine-2-yl)ethyl]acetamide] (TTA-A2) (.3, 1, or 3 mg/kg) on motivation for nicotine, as measured by nicotine self-administration on a progressive ratio (PR) schedule, and nicotine- and cue-induced reinstatement for a response previously reinforced with nicotine delivery (n = 11 or 12 Long Evans rats/group). Furthermore, we examined the specificity of the TTA-A2 effects by characterizing its influence on PR responding for food (in the absence or presence of nicotine-potentiated responding), food- versus nicotine-induced cue-potentiated reinstatement for a response previously reinforced by food administration (n = 11 or 12 Wistar Hannover rats/group), and its ability to induce a conditioned place aversion. TTA-A2 dose-dependently decreased self-administration of nicotine on a PR schedule and the ability of both nicotine and a cue paired with nicotine to reinstate responding. The effects were specific for nicotine's incentive motivational properties, as TTA-A2 did not influence responding for food on a PR schedule but did attenuate the ability of nicotine to potentiate responding for food. Likewise, TTA-A2 did not alter food-induced cue-potentiated reinstatement for a response previously reinforced by food but did decrease nicotine-induced cue-potentiated reinstatement. Finally, TTA-A2 did not produce an aversive state, as indicated by a lack of ability to induce conditioned place aversion. These data suggest that T-type calcium channel antagonists have potential for alleviating nicotine addiction by selectively decreasing the incentive motivational properties of nicotine. Copyright © 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  10. Keeping It Real: A Toledo Public School Prepares Students for College and Career

    ERIC Educational Resources Information Center

    Dubin, Jennifer

    2014-01-01

    In this article, author Jennifer Dubin offers a look into the innovations taking place in the Toledo Technology Academy (TTA), a career-tech school within the public school system in Toledo, Ohio. TTA teaches students in grades 7 through 12 using a science, technology, engineering, and math (STEM) curriculum, in addition to the traditional…

  11. Bioenvironmental Engineering Career Ladder AFSC 907X0

    DTIC Science & Technology

    1991-05-01

    TTA 1 1 HQ USAF/DPPE 1 HQ USAF/SGPA ( BOLLING AFB DC 20332-6188) 1 1 HQ USAFE/DPAT 3 3 HQ USAFE/TTA 1 1 HSD/SOSP 1 1 NODAC 1 USAFOMS/OMDQ 1 USAFOMS...this report are available for use by operations and training officials. Mr Roberto Salinas developed the survey instrument, Ms Becky Hernandez provided

  12. The Effect of a Microprocessor Prosthetic Foot on Function and Quality of Life in Transtibial Amputees Who Are Limited Community Ambulators

    DTIC Science & Technology

    with greater range of motion and active power, will translate into improved functional performance, ambulatory safety (risk of falls) and quality of... life in trans-tibial amputees (TTA) who function as limited community ambulators. We will assess these outcomes in 54 veterans with TTA by randomizing

  13. Constructivist-Visual Mind Map Teaching Approach and the Quality of Students' Cognitive Structures

    ERIC Educational Resources Information Center

    Dhindsa, Harkirat S.; Makarimi-Kasim; Anderson, O. Roger

    2011-01-01

    This study compared the effects of a constructivist-visual mind map teaching approach (CMA) and of a traditional teaching approach (TTA) on (a) the quality and richness of students' knowledge structures and (b) TTA and CMA students' perceptions of the extent that a constructivist learning environment (CLE) was created in their classes. The sample…

  14. Enhancing teen pregnancy prevention in local communities: capacity building using the interactive systems framework.

    PubMed

    Duffy, Jennifer L; Prince, Mary Severson; Johnson, Erin E; Alton, Forrest L; Flynn, Shannon; Faye, Amy Mattison; Padgett, Polly Edwards; Rollison, Chris; Becker, Dana; Hinzey, Angela L

    2012-12-01

    Getting To Outcomes (GTO), an innovative framework for planning, implementing, evaluating, and sustaining interventions has been shown to be effective in helping community-based organizations (CBOs) introduce science-based approaches into their prevention work. However, the Interactive Systems Framework (ISF) suggests that adopting innovations like GTO requires a significant amount of capacity building through training and technical assistance (T/TA). In this study, 11 CBOs and three schools in South Carolina entered into a 3 year program of intense and proactive T/TA based on the ISF to learn how to apply an adaptation of GTO (Promoting Science-Based Approaches-Getting To Outcomes, PSBA-GTO) to their teen pregnancy prevention programs. Using semi-structured interviews, the partnering organizations were assessed at three points in time, pre-T/TA, 12 months, and post T/TA (30 months) for their performance of the steps of GTO in their work. The seven organizations which participated in T/TA until the end of the project received an average of 76 h of TA and 112 h of training per organization. Interview results showed increased performance of all 10 steps of PSBA-GTO by these organizations when conducting their teen pregnancy programs. These results suggest targeted and proactive T/TA can successfully bridge the gap between research and practice by using a three part delivery system, as prescribed in the ISF, which relies on an intermediary prevention support system to ensure accurate and effective translation of research to the everyday work of community-based practitioners.

  15. Efficacy of a two-tiered trauma team activation protocol in a Norwegian trauma centre.

    PubMed

    Rehn, M; Lossius, H M; Tjosevik, K E; Vetrhus, M; Østebø, O; Eken, T

    2012-02-01

    A registry-based analysis revealed imprecise informal one-tiered trauma team activation (TTA) in a primary trauma centre. A two-tiered TTA protocol was introduced and analysed to examine its impact on triage precision and resource utilization. Interhospital transfers and patients admitted by non-healthcare personnel were excluded. Undertriage was defined as the fraction of major trauma victims (New Injury Severity Score over 15) admitted without TTA. Overtriage was the fraction of TTA without major trauma. Of 1812 patients, 768 had major trauma. Overall undertriage was reduced from 28·4 to 19·1 per cent (P < 0·001) after system revision. Overall overtriage increased from 61·5 to 71·6 per cent, whereas the mean number of skilled hours spent per overtriaged patient was reduced from 6·5 to 3·5 (P < 0·001) and the number of skilled hours spent per major trauma victim was reduced from 7·4 to 7·1 (P < 0·001). Increasing age increased risk for undertriage and decreased risk for overtriage. Falls increased risk for undertriage and decreased risk for overtriage, whereas motor vehicle-related accidents showed the opposite effects. Patients triaged to a prehospital response involving an anaesthetist had less chance of both undertriage and overtriage. A two-tiered TTA protocol was associated with reduced undertriage and increased overtriage, while trauma team resource consumption was reduced. NCT00876564 (http://www.clinicaltrials.gov). Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

  16. Protocol for Reducing Time to Antibiotics in Pediatric Patients Presenting to an Emergency Department With Fever and Neutropenia: Efficacy and Barriers.

    PubMed

    Cohen, Clay; King, Amber; Lin, Chee Paul; Friedman, Gregory K; Monroe, Kathy; Kutny, Matthew

    2016-11-01

    Patients with febrile neutropenia are at high risk of morbidity and mortality from infectious causes. Decreasing time to antibiotic (TTA) administration is associated with improved patient outcomes. We sought to reduce TTA for children presenting to the emergency department with fever and neutropenia. In a prospective cohort study with historical comparison, TTA administration was evaluated in patients with neutropenia presenting to the Children's of Alabama Emergency Department. A protocol was established to reduce delays in antibiotic administration and increase the percentage of patients who receive treatment within 60 minutes of presentation. One hundred pre-protocol patient visits between August 2010 and December 2011 were evaluated and 153 post-protocol visits were evaluated between August 2012 and September 2013. We reviewed individual cases to determine barriers to rapid antibiotic administration. Antibiotics were administered in 96.9 ± 57.8 minutes in the pre-protocol patient group, and only 35% of patients received antibiotics within 60 minutes of presentation and 70% received antibiotics within 120 minutes. After implementation of the protocol, TTA for neutropenic patients was decreased to 64.3 ± 28.4 minutes (P < 0.0001) with 51.4% receiving antibiotics within 60 minutes and 93.2% within 120 minutes. Implementing a standard approach to patients at risk for neutropenia decreased TTA. There are numerous challenges in providing timely antibiotics to children with febrile neutropenia. Identified delays included venous access (time to effect of topical anesthetics, and difficulty obtaining access), physicians waiting on laboratory results, and antibiotic availability.

  17. Photon energy upconverting nanopaper: a bioinspired oxygen protection strategy.

    PubMed

    Svagan, Anna J; Busko, Dmitry; Avlasevich, Yuri; Glasser, Gunnar; Baluschev, Stanislav; Landfester, Katharina

    2014-08-26

    The development of solid materials which are able to upconvert optical radiation into photons of higher energy is attractive for many applications such as photocatalytic cells and photovoltaic devices. However, to fully exploit triplet-triplet annihilation photon energy upconversion (TTA-UC), oxygen protection is imperative because molecular oxygen is an ultimate quencher of the photon upconversion process. So far, reported solid TTA-UC materials have focused mainly on elastomeric matrices with low barrier properties because the TTA-UC efficiency generally drops significantly in glassy and semicrystalline matrices. To overcome this limit, for example, combine effective and sustainable annihilation upconversion with exhaustive oxygen protection of dyes, we prepare a sustainable solid-state-like material based on nanocellulose. Inspired by the structural buildup of leaves in Nature, we compartmentalize the dyes in the liquid core of nanocellulose-based capsules which are then further embedded in a cellulose nanofibers (NFC) matrix. Using pristine cellulose nanofibers, a sustainable and environmentally friendly functional nanomaterial with ultrahigh barrier properties is achieved. Also, an ensemble of sensitizers and emitter compounds are encapsulated, which allow harvesting of the energy of the whole deep-red sunlight region. The films demonstrate excellent lifetime in synthetic air (20.5/79.5, O2/N2)-even after 1 h operation, the intensity of the TTA-UC signal decreased only 7.8% for the film with 8.8 μm thick NFC coating. The lifetime can be further modulated by the thickness of the protective NFC coating. For comparison, the lifetime of TTA-UC in liquids exposed to air is on the level of seconds to minutes due to fast oxygen quenching.

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hagland, Hanne R.; Nilsson, Linn I.H.; Burri, Lena

    Highlights: Black-Right-Pointing-Pointer We investigated mechanisms of mitochondrial regulation in rat hepatocytes. Black-Right-Pointing-Pointer Tetradecylthioacetic acid (TTA) was employed to activate mitochondrial oxidation. Black-Right-Pointing-Pointer Mitochondrial biogenesis and respiration were induced. Black-Right-Pointing-Pointer It was confirmed that PPAR target genes were induced. Black-Right-Pointing-Pointer The mechanism involved activation mTOR. -- Abstract: The hypolipidemic effect of peroxisome proliferator-activated receptor (PPAR) activators has been explained by increasing mitochondrial fatty acid oxidation, as observed in livers of rats treated with the pan-PPAR activator tetradecylthioacetic acid (TTA). PPAR-activation does, however, not fully explain the metabolic adaptations observed in hepatocytes after treatment with TTA. We therefore characterized the mitochondrial effects,more » and linked this to signalling by the metabolic sensor, the mammalian target of rapamycin (mTOR). In hepatocytes isolated from TTA-treated rats, the changes in cellular content and morphology were consistent with hypertrophy. This was associated with induction of multiple mitochondrial biomarkers, including mitochondrial DNA, citrate synthase and mRNAs of mitochondrial proteins. Transcription analysis further confirmed activation of PPAR{alpha}-associated genes, in addition to genes related to mitochondrial biogenesis and function. Analysis of mitochondrial respiration revealed that the capacity of both electron transport and oxidative phosphorylation were increased. These effects coincided with activation of the stress related factor, ERK1/2, and mTOR. The protein level and phosphorylation of the downstream mTOR actors eIF4G and 4E-BP1 were induced. In summary, TTA increases mitochondrial respiration by inducing hypertrophy and mitochondrial biogenesis in rat hepatocytes, via adaptive regulation of PPARs as well as mTOR.« less

  19. Teaching Them All: An Exploratory Mixed Methods Study of African American Students' Perceptions of Their Middle School's Culture

    ERIC Educational Resources Information Center

    Hankerson, Henry

    2009-01-01

    Research indicates school culture impacts student achievement. At Teach Them All Middle School (TTA), an achievement gap exists between African American and White students. The purpose of the current study was to examine the perceptions of African American students concerning the school culture at TTA. The research questions explored the…

  20. The Developmental Course of Community Service across the Transition to Adulthood in a National U.S. Sample

    ERIC Educational Resources Information Center

    Wray-Lake, Laura; Schulenberg, John; Keyes, Katherine M.; Shubert, Jennifer

    2017-01-01

    Despite the importance of community service for the well-being of individuals and communities, relatively little is known about the developmental course of community service during the transition to adulthood (TTA). This study tested competing hypotheses about change in community service across the TTA by estimating latent growth models from Ages…

  1. Using lead chalcogenide nanocrystals as spin mixers: a perspective on near-infrared-to-visible upconversion.

    PubMed

    Nienhaus, Lea; Wu, Mengfei; Bulović, Vladimir; Baldo, Marc A; Bawendi, Moungi G

    2018-03-01

    The process of upconversion leads to emission of photons higher in energy than the incident photons. Near-infrared-to-visible upconversion, in particular, shows promise in sub-bandgap sensitization of silicon and other optoelectronic materials, resulting in potential applications ranging from photovoltaics that exceed the Shockley-Queisser limit to infrared imaging. A feasible mechanism for near-infrared-to-visible upconversion is triplet-triplet annihilation (TTA) sensitized by colloidal nanocrystals (NCs). Here, the long lifetime of spin-triplet excitons in the organic materials that undergo TTA makes upconversion possible under incoherent excitation at relatively low photon fluxes. Since this process relies on optically inactive triplet states, semiconductor NCs are utilized as efficient spin mixers, absorbing the incident light and sensitizing the triplet states of the TTA material. The state-of-the-art system uses rubrene with a triplet energy of 1.14 eV as the TTA medium, and thus allows upconversion of light with photon energies above ∼1.1 eV. In this perspective, we review the field of lead sulfide (PbS) NC-sensitized near-infrared-to-visible upconversion, discuss solution-based upconversion, and highlight progress made on solid-state upconversion devices.

  2. A strontium-90 sequestrant for first-aid treatment of radiation emergency.

    PubMed

    Haratake, Mamoru; Hatanaka, Eisuke; Fuchigami, Takeshi; Akashi, Makoto; Nakayama, Morio

    2012-01-01

    In this study, hydrophilic porous polymer beads with phosphonic acid groups (PGMA-EGDMA-TTA-MP) were synthesized, and assessed as a radioactive strontium-90 sequestrant for the treatment of the radiation emergency. Strontium ions were rapidly absorbed into the blood from the gastrointestinal (GI) tract after oral administration to rats, and distributed to the target organ, i.e., bones. Over 40% of the administered strontium was absorbed into the blood, while the remainder was discharged in the feces within 48 h after the administration. When the PGMA-EGDMA-TTA-MP beads were administered to rats subsequent to the strontium solution, the strontium had accumulated less in the femur. Consequently, the oral administration of the PGMA-EGDMA-TTA-MP beads was effective in suppressing the absorption of strontium from the GI tract.

  3. Bipolar molecular composites: a new class of high-electron-mobility organic solids

    NASA Astrophysics Data System (ADS)

    Lin, Liang-Bih; Jenekhe, Samson A.; Borsenberger, Paul M.

    1997-10-01

    We describe high electron mobility in organic solids in the form of bipolar molecular composites of N,N'-bis(1,2-dimethylpropyl)-1,4,5,8-naphthalenetetracarboxylic diimide (NTDI) and tri-p-tolylaniine (TTA). The electron mobility in the NTDI/TTA composites is ~2 x 10 cm2/Vs, which is a factor of 4 to 6 higher than in pure NTDI and isone of the highest values reported for disordered organic solids. The field and temperature dependencies of the charge mobility can be described using the disorder formalism due to Bassler and co-workers, which provides an estimation of the energy width σ of the hopping site manifold. Analysis of the data gave σ=0.081 and 0.060 eV for the electron and hole mobilities in a NTDI/TTA composite of 0.5510.45 molar ratio. The energetic disorder for electron transport in the bipolar composites is substantially lower than for pure NTDI, which is 0.093 eV. The results suggest that the observed enhancement arises from a substantial reduction of energetic disorder in the electron transport manifold of the bipolar composites. The reduction of energetic disorder may be due to intermolecular charge transfer between NTDI and TTA. Such a charge transfer could stabilize the electron transport manifold by better charge delocalization, and consequently, less energetic disorder. Another possible reason for the observed enhanced electron mobility is the reduction of NTDI dimers that can act as carrier traps by the presence of TTA molecules in the bipolar composites. These results also suggest that bipolar composites represent a promising new class of high electron mobility organic solids.

  4. Pediatric emergency department triage-based pain guideline utilizing intranasal fentanyl: Effect of implementation.

    PubMed

    Schoolman-Anderson, Kristin; Lane, Roni D; Schunk, Jeff E; Mecham, Nancy; Thomas, Richard; Adelgais, Kathleen

    2018-01-16

    Pain management guidelines in the emergency department (ED) may reduce time to analgesia administration (TTA). Intranasal fentanyl (INF) is a safe and effective alternative to intravenous opiates. The effect of an ED pain management guideline providing standing orders for nurse-initiated administration of intranasal fentanyl (INF) is not known. The objective of this study was to determine the impact of a pediatric ED triage-based pain protocol utilizing intranasal fentanyl (INF) on time to analgesia administration (TTA) and patient and parent satisfaction. This was a prospective study of patients 3-17 years with an isolated orthopedic injury presenting to a pediatric ED before and after instituting a triage-based pain guideline allowing for administration of INF by triage nurses. Our primary outcome was median TTA and secondary outcomes included the proportion of patients who received INF for pain, had unnecessary IV placement, and patient and parent satisfaction. We enrolled 132 patients; 72 pre-guideline, 60 post-guideline. Demographics were similar between groups. Median TTA was not different between groups (34.5 min vs. 33 min, p = .7). Utilization of INF increased from 41% pre-guideline to 60% post-guideline (p = .01) and unnecessary IV placement decreased from 24% to 0% (p = .002). Patients and parents preferred the IN route for analgesia administration. A triage-based pain protocol utilizing INF did not reduce TTA, but did result in increased INF use, decreased unnecessary IV placement, and was preferred by patients and parents to IV medication. INF is a viable analgesia alternative for children with isolated extremity injuries. Copyright © 2018. Published by Elsevier Inc.

  5. Amplified Photon Upconversion by Photonic Shell of Cholesteric Liquid Crystals.

    PubMed

    Kang, Ji-Hwan; Kim, Shin-Hyun; Fernandez-Nieves, Alberto; Reichmanis, Elsa

    2017-04-26

    As an effective platform to exploit triplet-triplet-annihilation-based photon upconversion (TTA-UC), microcapsules composed of a fluidic UC core and photonic shell are microfluidically prepared using a triple emulsion as the template. The photonic shell consists of cholesteric liquid crystals (CLCs) with a periodic helical structure, exhibiting a photonic band gap. Combined with planar anchoring at the boundaries, the shell serves as a resonance cavity for TTA-UC emission and enables spectral tuning of the UC under low-power-density excitation. The CLC shell can be stabilized by introducing a polymerizable mesogen in the LC host. Because of the microcapsule spherical symmetry, spontaneous emission of the delayed fluorescence is omnidirectionally amplified at the edge of the stop band. These results demonstrate the range of opportunities provided by TTA-UC systems for the future design of low-threshold photonic devices.

  6. Evaluation of a Powered Ankle-Foot Prosthesis during Slope Ascent Gait

    PubMed Central

    2016-01-01

    Passive prosthetic feet lack active plantarflexion and push-off power resulting in gait deviations and compensations by individuals with transtibial amputation (TTA) during slope ascent. We sought to determine the effect of active ankle plantarflexion and push-off power provided by a powered prosthetic ankle-foot (PWR) on lower extremity compensations in individuals with unilateral TTA as they walked up a slope. We hypothesized that increased ankle plantarflexion and push-off power would reduce compensations commonly observed with a passive, energy-storing-returning prosthetic ankle-foot (ESR). We compared the temporal spatial, kinematic, and kinetic measures of ten individuals with TTA (age: 30.2 ± 5.3 yrs) to matched abled-bodied (AB) individuals during 5° slope ascent. The TTA group walked with an ESR and separately with a PWR. The PWR produced significantly greater prosthetic ankle plantarflexion and push-off power generation compared to an ESR and more closely matched AB values. The PWR functioned similar to a passive ESR device when transitioning onto the prosthetic limb due to limited prosthetic dorsiflexion, which resulted in similar deviations and compensations. In contrast, when transitioning off the prosthetic limb, increased ankle plantarflexion and push-off power provided by the PWR contributed to decreased intact limb knee extensor power production, lessening demand on the intact limb knee. PMID:27977681

  7. Evaluation of a Powered Ankle-Foot Prosthesis during Slope Ascent Gait.

    PubMed

    Rábago, Christopher A; Aldridge Whitehead, Jennifer; Wilken, Jason M

    2016-01-01

    Passive prosthetic feet lack active plantarflexion and push-off power resulting in gait deviations and compensations by individuals with transtibial amputation (TTA) during slope ascent. We sought to determine the effect of active ankle plantarflexion and push-off power provided by a powered prosthetic ankle-foot (PWR) on lower extremity compensations in individuals with unilateral TTA as they walked up a slope. We hypothesized that increased ankle plantarflexion and push-off power would reduce compensations commonly observed with a passive, energy-storing-returning prosthetic ankle-foot (ESR). We compared the temporal spatial, kinematic, and kinetic measures of ten individuals with TTA (age: 30.2 ± 5.3 yrs) to matched abled-bodied (AB) individuals during 5° slope ascent. The TTA group walked with an ESR and separately with a PWR. The PWR produced significantly greater prosthetic ankle plantarflexion and push-off power generation compared to an ESR and more closely matched AB values. The PWR functioned similar to a passive ESR device when transitioning onto the prosthetic limb due to limited prosthetic dorsiflexion, which resulted in similar deviations and compensations. In contrast, when transitioning off the prosthetic limb, increased ankle plantarflexion and push-off power provided by the PWR contributed to decreased intact limb knee extensor power production, lessening demand on the intact limb knee.

  8. Magnetic Field Effect in Conjugated Molecules-Based Devices

    DTIC Science & Technology

    2017-10-23

    triplet annihilation process (TTA) process in charge- balanced polymer light emitting diode (PLED) containing a super yellow poly-(phenylene vinylene...current density. Our results demonstrate a clear correlation between TTA process and current density as well as temperature in charge- balanced SY-PPV...dimethyl sulfoxide (DMSO) (7:3, v/v) at 60 °C for 12 h inside the nitrogen -filled glove box. The perovskite films were spin-cast by a consecutive two-step

  9. Abnormal temperature dependent behaviors of intersystem crossing and triplet-triplet annihilation in organic planar heterojunction devices

    NASA Astrophysics Data System (ADS)

    Xiang, Jie; Chen, Yingbing; Yuan, De; Jia, Weiyao; Zhang, Qiaoming; Xiong, Zuhong

    2016-09-01

    Anomalous temperature dependent magneto-electroluminescence was observed at low and high magnetic field strength from organic planar heterojunction devices incorporated common phosphorescent host materials of N,N'-dicarbazolyl-3,5-benzene (mCP) or 4,4'-N,N'-dicarbazole-biphenyl (CBP) as an emissive layer. We found that intersystem crossing became stronger with decreasing temperature and that triplet-triplet annihilation (TTA) occurred at room temperature but ceased at low temperature. Analyses of the electroluminescence spectra of these devices and their temperature dependences indicated that the population of exciplex states increased at low temperature, which caused the abnormal behavior of intersystem crossing. Additionally, long lifetime of the excitons within mCP or CBP layer may allow TTA to occur at room temperature, while the reduced population of excitons at low temperature may account for the disappearance of TTA even though the excitons had increased lifetime.

  10. Temporal triangular alopecia and a review of 52 past cases.

    PubMed

    Yamazaki, Masashi; Irisawa, Ryokichi; Tsuboi, Ryoji

    2010-04-01

    Temporal triangular alopecia (TTA) is a circumscribed, non-cicatricial form of alopecia confined to the frontotemporal region. The patient, a 15-year-old boy, was noticed at birth to have an alopecial area, sized 1.5 cm x 2.5 cm, in the right temporal region. Microscopic examination revealed miniaturized hair follicles accompanied by differentiated sebaceous glands. We have provided a synopsis of the past 52 cases. Of the 53 cases of TTA including our case, more than half (55.8%) were detected in childhood between the ages of 2 and 9 years, while 36.5% were detected at birth and only 3.8% (only two cases) in adulthood. There were three familial cases. Several congenital diseases were associated with the condition, for example, phakomatosis pigmentovascularis, Down syndrome and Dandy-Walker malformation. This information suggests that TTA can be recognized as a hamartomatous mosaic disease.

  11. Exploiting the benefit of S0 → T1 excitation in triplet-triplet annihilation upconversion to attain large anti-stokes shifts: tuning the triplet state lifetime of a tris(2,2'-bipyridine) osmium(ii) complex.

    PubMed

    Liu, Dongyi; Zhao, Yingjie; Wang, Zhijia; Xu, Kejing; Zhao, Jianzhang

    2018-03-07

    Os(ii) complexes are particularly interesting for triplet-triplet annihilation (TTA) upconversion, due to the strong direct S 0 → T 1 photoexcitation, as in this way, energy loss is minimized and large anti-Stokes shift can be achieved for TTA upconversion. However, Os(bpy) 3 has an intrinsic short T 1 state lifetime (56 ns), which is detrimental for the intermolecular triplet-triplet energy transfer (TTET), one of the crucial steps in TTA upconversion. In order to prolong the triplet state lifetime, we prepared an Os(ii) tris(bpy) complex with a Bodipy moiety attached, so that an extended T 1 state lifetime is achieved by excited state electronic configuration mixing or triplet state equilibrium between the coordination center-localized state ( 3 MLCT state) and Bodipy ligand-localized state ( 3 IL state). With steady-state and time-resolved transient absorption/emission spectroscopy, we proved that the 3 MLCT is slightly above the 3 IL state (by 0.05 eV), and the triplet state lifetime was prolonged by 31-fold (from 56 ns to 1.73 μs). The TTA upconversion quantum yield was increased by 4-fold as compared to that of the unsubstituted Os(ii) complex.

  12. Size speed bias or size arrival effect-How judgments of vehicles' approach speed and time to arrival are influenced by the vehicles' size.

    PubMed

    Petzoldt, Tibor

    2016-10-01

    Crashes at railway level crossings are a key problem for railway operations. It has been suggested that a potential explanation for such crashes might lie in a so-called size speed bias, which describes the phenomenon that observers underestimate the speed of larger objects, such as aircraft or trains. While there is some evidence that this size speed bias indeed exists, it is somewhat at odds with another well researched phenomenon, the size arrival effect. When asked to judge the time it takes an approaching object to arrive at a predefined position (time to arrival, TTA), observers tend to provide lower estimates for larger objects. In that case, road users' crossing decisions when confronted with larger vehicles should be rather conservative, which has been confirmed in multiple studies on gap acceptance. The aim of the experiment reported in this paper was to clarify the relationship between size speed bias and size arrival effect. Employing a relative judgment task, both speed and TTA estimates were assessed for virtual depictions of a train and a truck, using a car as a reference to compare against. The results confirmed the size speed bias for the speed judgments, with both train and truck being perceived as travelling slower than the car. A comparable bias was also present in the TTA estimates for the truck. In contrast, no size arrival effect could be found for the train or the truck, neither in the speed nor the TTA judgments. This finding is inconsistent with the fact that crossing behaviour when confronted with larger vehicles appears to be consistently more conservative. This discrepancy might be interpreted as an indication that factors other than perceived speed or TTA play an important role for the differences in gap acceptance between different types of vehicles. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vorobev, A.M.; Kuzmina, V.P.

    A method is described for determining Pu in the presence of large quantities of U. Pu is extracted using thenoyltrifluoroacetone (TTA) and precipitated using bismuth phosphate. In contrast to U (VI), plutonium (IV) is easily separated by TTA from 1M nitric acid and lends itself to quantitative precipitation. The yield of Pu amounted to 90%. The presence of U/sup 235/ in quantities exceeding 200-fold the Pu content did not influence the determination in 10-mg specimens. The order of error was plus or minus 20%. (R.V.J.)

  14. Triplet-Triplet Annihilation Photon Upconversion in Polymer Thin Film: Sensitizer Design.

    PubMed

    Jiang, Xinpeng; Guo, Xinyan; Peng, Jiang; Zhao, Dahui; Ma, Yuguo

    2016-05-11

    Efficient visible-to-UV photon upconversion via triplet-triplet annihilation (TTA) is accomplished in polyurethane (PU) films by developing new, powerful photosensitizers fully functional in the solid-state matrix. These rationally designed triplet sensitizers feature a bichromophoric scaffold comprising a tris-cyclometalated iridium(III) complex covalently tethered to a suitable organic small molecule. The very rapid intramolecular triplet energy transfer from the former to the latter is pivotal for achieving the potent sensitizing ability, because this process out-competes the radiative and nonradiative decays inherent to the metal complex and produces long-lived triplet excitons localized with the acceptor moiety readily available for intermolecular transfer and TTA. Nonetheless, compared to the solution state, the molecular diffusion is greatly limited in solid matrices, which even creates difficulty for the Dexter-type intramolecular energy transfer. This is proven by the experimental results showing that the sensitizing performance of the bichromophoric molecules strongly depends on the spatial distance separating the donor (D) and acceptor (A) units and that incorporating a longer linker between the D and A evidently curbs the TTA upconversion efficiency in PU films. Using a rationally optimized sensitizer structure in combination with 2,7-di-tert-butylpyrene as the annihilator/emitter, the doped polyurethane (PU) films demonstrate effective visible-to-UV upconverted emission signal under noncoherent-light irradiation, attaining an upconversion quantum yield of 2.6%. Such quantum efficiency is the highest value so far reported for the visible-to-UV TTA systems in solid matrices.

  15. Constructivist-Visual Mind Map Teaching Approach and the Quality of Students' Cognitive Structures

    NASA Astrophysics Data System (ADS)

    Dhindsa, Harkirat S.; Makarimi-Kasim; Roger Anderson, O.

    2011-04-01

    This study compared the effects of a constructivist-visual mind map teaching approach (CMA) and of a traditional teaching approach (TTA) on (a) the quality and richness of students' knowledge structures and (b) TTA and CMA students' perceptions of the extent that a constructivist learning environment (CLE) was created in their classes. The sample of the study consisted of six classes (140 Form 3 students of 13-15 years old) selected from a typical coeducational school in Brunei. Three classes (40 boys and 30 girls) were taught using the TTA while three other classes (41 boys and 29 girls) used the CMA, enriched with PowerPoint presentations. After the interventions (lessons on magnetism), the students in both groups were asked to describe in writing their understanding of magnetism accrued from the lessons. Their written descriptions were analyzed using flow map analyses to assess their content knowledge and its organisation in memory as evidence of cognitive structure. The extent of CLE was measured using a published CLE survey. The results showed that the cognitive structures of the CMA students were more extensive, thematically organised and richer in interconnectedness of thoughts than those of TTA students. Moreover, CMA students also perceived their classroom learning environment to be more constructivist than their counterparts. It is, therefore, recommended that teachers consider using the CMA teaching technique to help students enrich their understanding, especially for more complex or abstract scientific content.

  16. Preparation and luminescence properties of organogel doped with Eu(TTA)3phen complex

    NASA Astrophysics Data System (ADS)

    Cocca, M.; Di Lorenzo, M. L.; Avella, M.; Gentile, G.; Aubouy, L.; Della Pirreira, M.; Gutiérrez-Tauste, D.; Kennedy, M.; Doran, J.; Norton, B.

    2012-07-01

    In this contribution we report the preparation and the luminescence property of Eu(TTA)3phen complex doped toluene gels. Gels were prepared by using either a low molecular weight gelator, 12-hydroxystearic acid (HSA), or a macromolecular gelator, syndiotactic polymethylmethacrylate (s-PMMA). The gelation properties and their reversible behavior from solid-like to liquid systems have been investigated. In addition, photophysical investigations, as well as morphology, thermal properties and ageing behavior of the gels were analyzed as a function of composition of the gels.

  17. New Triplet Sensitization Routes for Photon Upconversion: Thermally Activated Delayed Fluorescence Molecules, Inorganic Nanocrystals, and Singlet-to-Triplet Absorption.

    PubMed

    Yanai, Nobuhiro; Kimizuka, Nobuo

    2017-10-17

    Photon upconversion based on triplet-triplet annihilation (TTA-UC) has attracted much interest because of its possible applications to renewable energy production and biological fields. In particular, the UC of near-infrared (NIR) light to visible (vis) light is imperative to overcome the Shockley-Queisser limit of single-junction photovoltaic cells, and the efficiency of photocatalytic hydrogen production from water can also be improved with the aid of vis-to-ultraviolet (UV) UC. However, both processes have met limitations in the wavelength range, efficiency, and sensitivity for weak incident light. This Account describes recent breakthroughs that solve these major problems, new triplet sensitization routes to significantly enlarge the range of conversion wavelength by minimizing the energy loss during intersystem crossing (ISC) of triplet sensitizers or bypassing the ISC process. The photochemical processes of TTA-UC in general start with the absorption of longer wavelength incident light by triplet sensitizers, which generate the triplet states via ISC. This ISC inevitably accompanies the energy loss of hundreds of millielectronvolts, which significantly limits the TTA-UC with large anti-Stokes shifts. The small S 1 -T 1 gap of molecules showing thermally activated delayed fluorescence (TADF) allows the sensitization of emitters with the highest T 1 and S 1 energy levels ever employed in TTA-UC, which results in efficient vis-to-UV UC. As alternatives to molecular sensitizers in the NIR region, inorganic nanocrystals with broad NIR absorption bands have recently been shown to work as effective sensitizers for NIR-to-vis TTA-UC. Their small exchange splitting minimizes the energy loss during triplet sensitization. The modification of nanocrystal surfaces with organic acceptors via coordination bonds allows efficient energy transfer between the components and succeeding TTA processes. To remove restrictions on the energy loss during ISC, molecules with direct singlet-to-triplet (S-T) excitation are employed as triplet sensitizers. Although the S-T absorption is spin forbidden, large spin-orbital coupling occurs for appropriately designed metal complexes, which allow S-T absorption in the NIR region with large absorption coefficients. While the triplet lifetime of such S-T absorption sensitizers is often short (less than microsecond), the integration of the molecular sensitizers with emitter assemblies allows facile Dexter energy transfer to the surrounding emitter molecules, leading to efficient NIR-to-vis UC emission through triplet energy migration (TEM) in the condensed state. By judicious modification of the chromophore structures, the first example of NIR-to-blue UC has also been achieved. It is essential to combine these new triplet sensitization routes with an upconverted energy collection (UPCON) approach in molecular assemblies to effectively populate emitter triplets and to overcome remaining issues including back energy transfer. We propose two overall materials designs for the TEM-UPCON strategy, core-shell-shell structures and trilayer structures composed of triplet donor, acceptor, and energy collector. The fusion between triplet science and chemistry of self-assembly would overcome previous difficulties of NIR-to-vis and vis-to-UV TTA-UC toward real-world applications ranging from energy to biology.

  18. Non-compliance with ACS-COT recommended criteria for full trauma team activation is associated with undertriage deaths.

    PubMed

    Tignanelli, Christopher J; Vander Kolk, Wayne E; Mikhail, Judy N; Delano, Matthew J; Hemmila, Mark R

    2017-11-21

    The appropriate triage of acutely injured patients within a trauma system is associated with improved rates of mortality and optimal resource utilization. The American College of Surgeons Committee on Trauma (ACS-COT) put forward six minimum criteria (ACS-6) for full trauma team activation (TTA). We hypothesized that ACS-COT verified trauma center compliance with these criteria is associated with low under-triage rates and improved overall mortality. Data from a state-wide collaborative quality initiative was utilized. We used data collected from 2014 through 2016 at 29 ACS verified level 1 and 2 trauma centers. Inclusion criteria were: adult patients (≥16 years) and ISS ≥5. Quantitative data existed to analyze four of the ACS-6 criteria (ED SBP≤90 mmHg, respiratory compromise/intubation, central GSW, and GCS<9). Patients were considered to be under-triaged if they had major trauma (ISS>15) and did not receive a full TTA. 51,792 patients were included in the study. Compliance with ACS-6 minimum criteria for full TTA varied from 51% to 82%. Presence of any ACS-6 criteria was associated with a high intervention rate and significant risk of mortality (OR 16.7, 95% CI 15.2-18.3, p<0.001). Of the 1004 deaths that were not a full activation, 433 (43%) were classified as under-triaged, and 301 (30%) had at least one ACS-6 criteria present. Under-triaged patients with any ACS-6 criteria were more likely to die than those who were not under-triaged (30% vs 21%, p=0.001). GCS<9 and need for emergent intubation were the ACS-6 criteria most frequently associated with under-triage mortality. Compliance with ACS-COT minimum criteria for full TTA remains sub-optimal and undertriage is associated with increased mortality. This data suggests that the most efficient quality improvement measure around triage should be ensuring compliance with the ACS-6 criteria. This study suggests that practice pattern modification to more strictly adhere to the minimum ACS-COT criteria for full TTA will save lives. Diagnostic Tests or Criteria, Level III.

  19. Margins of stability in young adults with traumatic transtibial amputation walking in destabilizing environments✫

    PubMed Central

    Beltran, Eduardo J.; Dingwell, Jonathan B.; Wilken, Jason M.

    2014-01-01

    Understanding how lower-limb amputation affects walking stability, specifically in destabilizing environments, is essential for developing effective interventions to prevent falls. This study quantified mediolateral margins of stability (MOS) and MOS sub-components in young individuals with traumatic unilateral transtibial amputation (TTA) and young able-bodied individuals (AB). Thirteen AB and nine TTA completed five 3-minute walking trials in a Computer Assisted Rehabilitation ENvironment (CAREN) system under three each of three test conditions: no perturbations, pseudo-random mediolateral translations of the platform, and pseudo-random mediolateral translations of the visual field. Compared to the unperturbed trials, TTA exhibited increased mean MOS and MOS variability during platform and visual field perturbations (p < 0.010). Also, AB exhibited increased mean MOS during visual field perturbations and increased MOS variability during both platform and visual field perturbations (p < 0.050). During platform perturbations, TTA exhibited significantly greater values than AB for mean MOS (p < 0.050) and MOS variability (p < 0.050); variability of the lateral distance between the center of mass (COM) and base of support at initial contact (p < 0.005); mean and variability of the range of COM motion (p < 0.010); and variability of COM peak velocity (p < 0.050). As determined by mean MOS and MOS variability, young and otherwise healthy individuals with transtibial amputation achieved stability similar to that of their able-bodied counterparts during unperturbed and visually-perturbed walking. However, based on mean and variability of MOS, unilateral transtibial amputation was shown to have affected walking stability during platform perturbations. PMID:24444777

  20. A Comparison of Angular Values of the Pelvic Limb with Normal and Medial Patellar Luxation Stifles in Chihuahua Dogs Using Radiography and Computed Tomography.

    PubMed

    Phetkaew, Thitaporn; Kalpravidh, Marissak; Penchome, Rampaipat; Wangdee, Chalika

    2018-02-01

     This article aimed to determine and compare the angular values of the pelvic limb in normal and medial patellar luxation (MPL) stifles in Chihuahuas using radiography and computed tomographic (CT) scan, to identify the relationship between pelvic limb angles and severity of MPL. In addition, radiographic and CT images were compared to determine the more suitable method of limb deformity assessment.  Sixty hindlimbs of Chihuahuas were divided into normal and grade 1, 2, 3 and 4 MPL groups. The pelvic limb angles in frontal and sagittal planes were evaluated on radiography and CT scan. Femoral and tibial torsion angles (FTA and TTA) were evaluated only by CT scan. All angles were compared among normal and MPL stifles and between radiography and CT scan.  Based on the CT scan, the mechanical lateral distal femoral angle (mLDFA), anatomical caudal proximal femoral angle (aCdPFA), and TTA were related to the severity of MPL. The mLDFA and TTA were significantly increased ( p  < 0.05) in grade 4 MPL, while the aCdPFA was significantly decreased in grade 2, 3 and 4 MPL groups. There were significant differences of many angles between radiography and CT scan.  The angles related to MPL in Chihuahuas are aLDFA, mLDFA, aCdPFA and TTA. Radiography had some limitations for evaluating pelvic limb angles. The caudocranial radiograph is recommended for the assessment of the distal femoral angles, while the craniocaudal radiograph is for the tibial angles. Schattauer GmbH Stuttgart.

  1. [Clinical evaluation of anaerobic infections in patients with bronchopulmonary infections diagnosed by transtracheal aspiration].

    PubMed

    Konishi, M; Mori, K; Yoshimoto, E; Takahashi, K; Majima, T; Ueda, K; Murakawa, K; Sakamoto, M; Maeda, K; Mikasa, K; Narita, N; Sano, R; Masutani, T

    1999-07-01

    We evaluated the clinical and bacteriologic features in the patients with bronchopulmonary infections isolated anaerobes from transtracheal aspirates between April 1990 and March 1998. Some anaerobe was isolated in 42 (10.9%) in 387 patients whom we performed transtracheal aspiration (TTA), in 42 (15.7%) of 268 in whom some organism was isolated from TTA, or in 42 (16.3%) of 257 patients in whom some bacterium excluding acid-fast bacteria, fungi or mycoplasma from TTA. The isolation rate of anaerobic bacteria was 93.3% in the patients with lung abscess, 22.7% in the patients with nosocomial pneumonia, 19.4% in the patients with community-acquired pneumonia, 26.7% in the patients with acute exacerbation of chronic lower respiratory tract infection (CLRTI), 1.6% in the patients with persistent infection of CLRTI, and 3.0% in the patients with acute bronchitis, respectively. The major anaerobes, isolated from TTA, were Peptostreptococcus micros and Prevotella melaninogenica. The aerobic bacteria were isolated with anaerobic bacteria in 32 of 42 patients at the same time. The quantitive grade of colonial growth of anaerobes was equal to or more than aerobes in the patients with lung abscess and pneumonia. We mostly administrated 3rd generation cephems or carbapenems with or without clindamycin for the treatment of anaerobic infections. Forty-one of 42 patients were cured only by the therapy of antimicrobial agents, but pneumonia patient with lung cancer died in spite of adequate antimicrobial therapy. These results suggest that the anaerobic infections are important in the bronchopulmonary infections.

  2. Effect of cranial cruciate ligament deficiency, tibial plateau leveling osteotomy, and tibial tuberosity advancement on contact mechanics and alignment of the stifle in flexion.

    PubMed

    Kim, Stanley E; Pozzi, Antonio; Banks, Scott A; Conrad, Bryan P; Lewis, Daniel D

    2010-04-01

    To assess contact mechanics and 3-dimensional (3-D) joint alignment in cranial cruciate ligament (CCL)-deficient stifles before and after tibial plateau leveling osteotomy (TPLO) and tibial tuberosity advancement (TTA) with the stifle in 90 degrees of flexion. In vitro biomechanical study. Cadaveric pelvic limb pairs (n=8) from dogs weighing 28-35 kg. Contralateral limbs were assigned to receive TPLO or TTA. Digital pressure sensors were used to measure femorotibial contact area, peak and mean contact pressure, and peak pressure location with the limb under a load of 30% body weight and stifle flexion angle of 90 degrees . 3-D poses were obtained using a Microscribe digitizer. Specimens were tested under normal, CCL deficient, and treatment conditions. Significant disturbances in alignment were not observed after CCL transection, although medial contact area was 10% smaller than normal (P=.003). There were no significant differences in contact mechanics or alignment between normal and TTA conditions; TPLO induced 6 degrees varus angulation (P<.001), 26% decrease in lateral peak pressure (P=.027), and 18% increase in medial mean pressure (P=.008) when compared with normal. Cranial tibial subluxation is nominal in CCL-deficient stifles loaded in flexion. Stifle alignment and contact mechanics are not altered by TTA, whereas TPLO causes mild varus and a subsequent increase in medial compartment loading. Cranial tibial subluxation of CCL-deficient stifles may not occur during postures that load the stifle in flexion. The significance of minor changes in loading patterns after TPLO is unknown.

  3. Mechanisms of low-power noncoherent photon upconversion in metalloporphyrin-organic blue emitter systems in solution.

    PubMed

    Sugunan, Sunish K; Tripathy, Umakanta; Brunet, Sophie M K; Paige, Matthew F; Steer, Ronald P

    2009-07-30

    The mechanisms of noncoherent photon upconversion that involve triplet-triplet annihilation (TTA) in solution have been investigated for two model systems. ZnTPP (meso-tetraphenylporphine zinc) is used as the model visible light-absorbing metalloporphyrin because its S(1) fluorescence intensity can be used to monitor the initial rate of porphyrin triplet state production and because its S(2) fluorescence intensity can be used as a direct measure of the rate of porphyrin TTA. When perylene, which has a triplet energy lower than that of ZnTPP, is added as a signaling blue emitter (BE), the mechanism of photon upconversion involves triplet energy transfer from the porphyrin to the BE followed by TTA in the BE to form the fluorescent perylene S(1) state. The kinetics of this process have been characterized and are unremarkable. When coumarin 343 (C343), which has photophysical properties similar to those of perylene except that it has a much higher triplet energy than ZnTPP, is added as the signaling BE, emission from the ZnTPP S(2) state is quenched and fluorescence from the C343 grows in. Contrary to previous suggestions, the mechanism of photon upconversion in this system does not involve singlet energy transfer from the porphyrin S(2) state to the BE. Instead, ground-state C343 complexes with the ZnTPP triplet to form a triplet exciplex, which then undergoes TTA with a second ZnTPP triplet to give the fluorescent state of the BE in a three-center process.

  4. Determinants of the efficiency of photon upconversion by triplet-triplet annihilation in the solid state: zinc porphyrin derivatives in PVA.

    PubMed

    Rautela, Ranjana; Joshi, Neeraj K; Novakovic, Sacha; Wong, Wallace W H; White, Jonathan M; Ghiggino, Kenneth P; Paige, Matthew F; Steer, Ronald P

    2017-08-30

    Spectroscopic, photophysical and computational studies designed to expose and explain the differences in the efficiencies of non-coherent photon upconversion (NCPU) by triplet-triplet annihilation (TTA) have been carried out for a new series of alkyl-substituted diphenyl and tetraphenyl zinc porphyrins, both in fluid solution and in solid films. Systematic variations in the alkyl-substitution of the phenyl groups in both the di- and tetraphenyl porphyrins introduces small, but well-understood changes in their spectroscopic and photophysical properties and in their TTA efficiencies. In degassed toluene solution TTA occurs for all derivatives and produces the fluorescent S 2 product states in all cases. In PVA matrices, however, none of the di-phenylporphyrins exhibit measurable NCPU whereas all the tetraphenyl-substituted compounds remain upconversion-active. In PVA the NCPU efficiencies of the zinc tetraphenylporphyrins vary significantly with their steric characteristics; the most sterically crowded tetraphenyl derivative exhibits the greatest efficiency. DFT-D computations have been undertaken and help reveal the sources of these differences.

  5. Separation of tartronic and glyceric acids by simulated moving bed chromatography.

    PubMed

    Coelho, Lucas C D; Filho, Nelson M L; Faria, Rui P V; Ferreira, Alexandre F P; Ribeiro, Ana M; Rodrigues, Alírio E

    2018-08-17

    The SMB unit developed by the Laboratory of Separation and Reaction Engineering (FlexSMB-LSRE ® ) was used to perform tartronic acid (TTA) and glyceric acid (GCA) separation and to validate the mathematical model in order to determine the optimum operating parameters of an industrial unit. The purity of the raffinate and extract streams in the experiments performed were 80% and 100%, respectively. The TTA and GCA productivities were 79 and 115 kg per liter of adsorbent per day, respectively and only 0.50 cubic meters of desorbent were required per kilogram of products. Under the optimum operating conditions, which were determined through an extensive simulation study based on the mathematical model developed to predict the performance of a real SMB unit, it was possible to achieve a productivity of 86 kg of TTA and 176 kg of GCA per cubic meter of adsorbent per day (considering the typical commercial purity value of 97% for both compounds) with an eluent consumption of 0.30 cubic meters per kilogram of products. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Fast and long-range triplet exciton diffusion in metal-organic frameworks for photon upconversion at ultralow excitation power.

    PubMed

    Mahato, Prasenjit; Monguzzi, Angelo; Yanai, Nobuhiro; Yamada, Teppei; Kimizuka, Nobuo

    2015-09-01

    The conversion of low-energy light into photons of higher energy based on sensitized triplet-triplet annihilation upconversion (TTA-UC) has emerged as a promising wavelength-shifting methodology because it permits UC at excitation powers as low as the solar irradiance. However, its application has been significantly hampered by the slow diffusion of excited molecules in solid matrices. Here, we introduce metal-organic frameworks (MOFs) that promote TTA-UC by taking advantage of triplet exciton migration among fluorophores that are regularly aligned with spatially controlled chromophore orientations. We synthesized anthracene-containing MOFs with different molecular orientations, and the analysis of TTA-UC emission kinetics unveiled a high triplet diffusion rate with a micrometre-scale diffusion length. Surface modification of MOF nanocrystals with donor molecules and their encapsulation in glassy poly(methyl methacrylate) (PMMA) allowed the construction of molecular-diffusion-free solid-state upconverters, which lead to an unprecedented maximization of overall UC quantum yield at excitation powers comparable to or well below the solar irradiance.

  7. Photon Upconversion and Molecular Solar Energy Storage by Maximizing the Potential of Molecular Self-Assembly.

    PubMed

    Kimizuka, Nobuo; Yanai, Nobuhiro; Morikawa, Masa-Aki

    2016-11-29

    The self-assembly of functional molecules into ordered molecular assemblies and the fulfillment of potentials unique to their nanotomesoscopic structures have been one of the central challenges in chemistry. This Feature Article provides an overview of recent progress in the field of molecular self-assembly with the focus on the triplet-triplet annihilation-based photon upconversion (TTA-UC) and supramolecular storage of photon energy. On the basis of the integration of molecular self-assembly and photon energy harvesting, triplet energy migration-based TTA-UC has been achieved in varied molecular systems. Interestingly, some molecular self-assemblies dispersed in solution or organogels revealed oxygen barrier properties, which allowed TTA-UC even under aerated conditions. The elements of molecular self-assembly were also introduced to the field of molecular solar thermal fuel, where reversible photoliquefaction of ionic crystals to ionic liquids was found to double the molecular storage capacity with the simultaneous pursuit of switching ionic conductivity. A future prospect in terms of innovating molecular self-assembly toward molecular systems chemistry is also discussed.

  8. Voltage color tunable OLED with (Sm,Eu)-β-diketonate complex blend

    NASA Astrophysics Data System (ADS)

    Reyes, R.; Cremona, M.; Teotonio, E. E. S.; Brito, H. F.; Malta, O. L.

    2004-09-01

    Light emission from organic electroluminescent diodes (OLEDs) in which mixed samarium and europium β-diketonate complexes, [Sm 0.7Eu 0.3(TTA) 3(TPPO) 2], was used as the emitting layer is described. The electroluminescence spectra exhibit narrow peaks arising from 4f-intraconfigurational transitions of the Sm 3+ and Eu 3+ ions and a broad emission band attributed to the electrophosphorescence of the TTA ligand. The intensity ratio of the peaks determined by the bias voltage applied to the OLED, together with the ligand electrophosphorescence, allows to obtain a voltage-tunable color light source.

  9. Outcomes of dysvascular partial foot amputation and how these compare to transtibial amputation: a systematic review for the development of shared decision-making resources.

    PubMed

    Dillon, Michael P; Quigley, Matthew; Fatone, Stefania

    2017-03-14

    Dysvascular partial foot amputation (PFA) is a common sequel to advanced peripheral vascular disease. Helping inform difficult discussions between patients and practitioners about the level of PFA, or the decision to have a transtibial amputation (TTA) as an alternative, requires an understanding of the current research evidence on a wide range of topics including wound healing, reamputation, quality of life, mobility, functional ability, participation, pain and psychosocial outcomes, and mortality. The aim of this review was to describe a comprehensive range of outcomes of dysvascular PFA and compare these between levels of PFA and TTA. The review protocol was registered in PROSPERO (CRD42015029186). A systematic search of the literature was conducted using MEDLINE, EMBASE, psychINFO, AMED, CINAHL, ProQuest Nursing and Allied Health, and Web of Science. These databases were searched using MeSH terms and keywords relating to different amputation levels and outcomes of interest. Peer reviewed studies of original research-irrespective of the study design-were included if published in English between 1 January 2000, and 31 December 2015, and included discrete cohort(s) with dysvascular PFA or PFA and TTA. Outcomes of interest were rate of wound healing and complications, rate of ipsilateral reamputation, quality of life, functional ability, mobility, pain (i.e., residual limb or phantom pain), psychosocial outcomes (i.e., depression, anxiety, body image and self-esteem), participation, and mortality rate. Included studies were independently appraised by two reviewers. The McMaster Critical Review Forms were used to assess methodological quality and identify sources of bias. Data were extracted based on the Cochrane Consumers and Communication Review Group's data extraction template by a primary reviewer and checked for accuracy and clarity by a second reviewer. Findings are reported as narrative summaries given the heterogeneity of the literature, except for mortality and ipsilateral reamputation where data allowed for proportional meta-analyses. Twenty-nine unique articles were included in the review, acknowledging that some studies reported multiple outcomes. Eighteen studies reported all-cause proportionate mortality. A smaller number of studies reported outcomes related to functional ability (two), mobility (four), quality of life (three), ipsilateral reamputation (six) as well as wound healing and complications (four). No studies related to pain, participation or psychosocial outcomes met the inclusion criteria. Subjects were typically older and male and had diabetes among other comorbidities. More detailed information about the cohorts such as race or sociodemographic factors were reported in an ad hoc manner. Common sources of bias included contamination, co-intervention, or lack of operational definition for some outcomes (e.g., wound healing) as illustrative examples. Aside from mortality, there was limited evidence regarding outcomes of dysvascular PFA, particularly how outcomes differ between levels of PFA and TTA. Acknowledging that there is considerable uncertainty given the small body of literature on many topics where the risk of bias is high, the available evidence suggests that a large proportion of people with PFA experience delayed wound healing and ipsilateral reamputation. People with TTA have increased risk of mortality compared to those with PFA, which may reflect that those considered suitable candidates for TTA have more advanced systemic disease that also increases the risk of dying. Mobility and quality of life may be similar in people with PFA and TTA. CRD42015029186.

  10. Construction and modelling of an inducible positive feedback loop stably integrated in a mammalian cell-line.

    PubMed

    Siciliano, Velia; Menolascina, Filippo; Marucci, Lucia; Fracassi, Chiara; Garzilli, Immacolata; Moretti, Maria Nicoletta; di Bernardo, Diego

    2011-06-01

    Understanding the relationship between topology and dynamics of transcriptional regulatory networks in mammalian cells is essential to elucidate the biology of complex regulatory and signaling pathways. Here, we characterised, via a synthetic biology approach, a transcriptional positive feedback loop (PFL) by generating a clonal population of mammalian cells (CHO) carrying a stable integration of the construct. The PFL network consists of the Tetracycline-controlled transactivator (tTA), whose expression is regulated by a tTA responsive promoter (CMV-TET), thus giving rise to a positive feedback. The same CMV-TET promoter drives also the expression of a destabilised yellow fluorescent protein (d2EYFP), thus the dynamic behaviour can be followed by time-lapse microscopy. The PFL network was compared to an engineered version of the network lacking the positive feedback loop (NOPFL), by expressing the tTA mRNA from a constitutive promoter. Doxycycline was used to repress tTA activation (switch off), and the resulting changes in fluorescence intensity for both the PFL and NOPFL networks were followed for up to 43 h. We observed a striking difference in the dynamics of the PFL and NOPFL networks. Using non-linear dynamical models, able to recapitulate experimental observations, we demonstrated a link between network topology and network dynamics. Namely, transcriptional positive autoregulation can significantly slow down the "switch off" times, as compared to the non-autoregulated system. Doxycycline concentration can modulate the response times of the PFL, whereas the NOPFL always switches off with the same dynamics. Moreover, the PFL can exhibit bistability for a range of Doxycycline concentrations. Since the PFL motif is often found in naturally occurring transcriptional and signaling pathways, we believe our work can be instrumental to characterise their behaviour.

  11. Development and Pre-Clinical Evaluation of a Novel Prostate-Restricted Replication Competent Adenovirus-AD-IU-1

    DTIC Science & Technology

    2006-05-01

    CTCTGTTTGTGGA A A A TT TTA A A CTA CTGGTTTA A TTT CT TTA TTGGTTGTA A TA TGA CTA TTTTA CGTCA TA TA A CA A TTTTTA TT GTTTGT TA A A TGA CTTTA TTGTTTGTC A...radiotracer 1 was 0.8–1.2 Ci /mmol at end of synthesis (EOS). In comparison with the results reported in the literature,[15,25,33,34] several improvements in...99%, and the chemical purity of radiotracer 1 was 93%. The average (n ¼ 3–5) specific radio- activity of radiotracer 1 was 0.8–1.2 Ci /mmol at EOS

  12. Development and Characterization of Novel Bioluminecent Systems

    DTIC Science & Technology

    2013-07-01

    Ppy I108R. The following primers and their respective reverse compliments were used: Y447E, 5´- CT TTA ATT AAA TAC AAA GGA GAG CAG GTG GCC CCC GCT G...3´ [EcoRV] and I108R, 5´- GGA GTT GCA GTG GCG CCC GCG AAC GAC CGT TAT AAT GAA CGT-3´ [KasI] (bold represents the mutated codons, underlined...primers and their respective reverse compliments: Y447C, 5´- G AAG TCT TTA ATA AAA TAC AAA GGA TGT CAG GTG GCC CCC GCT G -3´ [PacI] and I108C, 5´- GGA

  13. Exciplex-Sensitized Triplet-Triplet Annihilation in Heterojunction Organic Thin-Film.

    PubMed

    Lin, Bo-Yen; Easley, Connor J; Chen, Chia-Hsun; Tseng, Po-Chen; Lee, Ming-Zer; Sher, Pin-Hao; Wang, Juen-Kai; Chiu, Tien-Lung; Lin, Chi-Feng; Bardeen, Christopher J; Lee, Jiun-Haw

    2017-03-29

    A new concept for organic light-emitting diodes (OLEDs) is presented, which is called exciplex-sensitized triplet-triplet annihilation (ESTTA). The exciplex formed at the organic heterojunction interface of 4,4',4″-tris(N-3-methyphenyl-N-phenyl-amino) triphenylamine and 9,10-bis(2'-naphthyl) anthracene (ADN) is used to sensitize the triplet-triplet annihilation (TTA) process on the ADN molecules. This results in a turn-on voltage (2.2 V) of the blue emission from the OLED below the bandgap (2.9 eV). From the transient electroluminescence measurement, blue emission totally came from the TTA process without direct recombination on the ADN molecules. The blue singlet exciton from the TTA process can be quenched by energy transfer to the exciplex, as revealed by transient photoluminescence measurements. This can be prevented by blocking the energy transfer path and improving the radiative recombination rate of blue emission. With the insertion of the "triplet diffusion and singlet blocking (TDSB)" layer and the incorporation of the dopant material, an ESTTA-OLED with external quantum efficiency of 5.1% was achieved, which consists of yellow and blue emission coming from the exciplex and ESTTA process, respectively.

  14. Kinetic Monte Carlo modeling of the efficiency roll-off in a multilayer white organic light-emitting device

    NASA Astrophysics Data System (ADS)

    Mesta, M.; van Eersel, H.; Coehoorn, R.; Bobbert, P. A.

    2016-03-01

    Triplet-triplet annihilation (TTA) and triplet-polaron quenching (TPQ) in organic light-emitting devices (OLEDs) lead to a roll-off of the internal quantum efficiency (IQE) with increasing current density J. We employ a kinetic Monte Carlo modeling study to analyze the measured IQE and color balance as a function of J in a multilayer hybrid white OLED that combines fluorescent blue with phosphorescent green and red emission. We investigate two models for TTA and TPQ involving the phosphorescent green and red emitters: short-range nearest-neighbor quenching and long-range Förster-type quenching. Short-range quenching predicts roll-off to occur at much higher J than measured. Taking long-range quenching with Förster radii for TTA and TPQ equal to twice the Förster radii for exciton transfer leads to a fair description of the measured IQE-J curve, with the major contribution to the roll-off coming from TPQ. The measured decrease of the ratio of phosphorescent to fluorescent component of the emitted light with increasing J is correctly predicted. A proper description of the J-dependence of the ratio of red and green phosphorescent emission needs further model refinements.

  15. Crystal structure, molecular docking, and biological activity of the zinc complexes with 2-thenoyltrifluoroacetone and N-donor heterocyclic ligands

    NASA Astrophysics Data System (ADS)

    Eshaghi Malekshah, Rahime; Salehi, Mehdi; Kubicki, Maciej; Khaleghian, Ali

    2017-12-01

    Two novel mononuclear complexes, [Zn (TTA) (bipy)Cl] (1) and [Zn (TTA) (phen)Cl] (2) (TTA = 4,4,4-Trifluoro-1-(2-furyl)-1,3-butanedione, phen = 1,10-phenanthroline and bipy 2, 2ʹ-bipyridine), were synthesized and fully characterized by elemental analyses, 1H NMR, UV-Vis, FTIR spectroscopy, and conductivity measurements. The crystal structures of these two mono-nuclear zinc (II) complexes were determined by X-ray single-crystal diffraction. The result of X-ray diffraction analyses revealed that both complexes have distorted tetragonal-pyramid structures. In MTT cytotoxicity studies, these Zn (II) complexes exhibited antitumor activity against MCF-7 and MKN-45 cell lines. It was also found that the proliferation rate of MCF-7 and MKN-45 cells decreased after treatment with the above-mentioned complexes. In addition, the apoptosis-inducing activity was assessed by AO/EB (Acridine Orange/Ethidium bromide) staining assay and found that they have the potential to act as effective metal-based anticancer drugs. Finally, the molecular docking studies showed that complex 2 strongly binds through minor groove with DNA by relative binding energy -7.33 kcal mol-1.

  16. Near-infrared emissive lanthanide hybridized nanofibrillated cellulose nanopaper as ultraviolet filter.

    PubMed

    Xue, Bailiang; Zhang, Zhao; Sun, Yongchang; Wang, Junjie; Jiang, Huie; Du, Min; Chi, Congcong; Li, Xinping

    2018-04-15

    The lanthanide complexes [Yb(fac) 3 (H 2 O) 2 , Yb(tta) 3 (H 2 O) 2 , Nd(tta) 3 (H 2 O) 2 ] functionalized nanofibrillated cellulose (Ln-NFC) nanopapers with near-infrared (NIR) luminescence and high transparency are rapidly fabricated after solvent exchange using a simple suction filtration film-making method. The effects of NFC and lanthanide complexes content on their photophysical properties of Ln-NFC nanopapers and their mechanism of UV filters are fully investigated. With increasing lanthanide complexes content in the Ln-NFC nanopaper, their transmittances are gradually decreased while their NIR luminescences are obviously increased. Yb-fac NFC nanopaper has high UVB block rate at 298 nm, whereas the high UVA block ratio of Ln-tta NFC nanopaper is observed at 345 nm. Ln-NFC nanopapers show a much higher photostability without decomposition under UV irradiation at 365 nm over 5 h. The emission spectra of the Ln-NFC nanopaper process the NIR luminescence of the corresponding lanthanide ions through the efficient triplet-triplet energy transfer process. Ln-NFC nanopapers can bring a brilliant future for UV filters, labeling fields and marking soft materials application. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Development of Phase-Stable Photon Upconverters for Efficient Solar Energy Utilization

    NASA Astrophysics Data System (ADS)

    Murakami, Yoichi

    Photon upconversion based on triplet-triplet annihilation (TTA) of excited triplet molecules is drawing attention due to its applicability for weak incident light, possessing a potential for improving efficiencies of solar energy conversion devices. Since energy transfer between triplet levels of different molecules and TTA are based on the Dexter mechanism, inter-molecular collision is necessary and hence the majority of previous studies have been done with organic solvents, which are volatile and flammable. This paper presents the development and characterization of phase-stable photon upconverters fabricated with ionic liquids, which are room temperature molten salts with negligible vapor pressure and high thermal stability. The employed aromatic molecules, which are carrier of photo-created energies and are non-polar (or weakly polar) molecules, are found to be stable in the polar environment of ionic liquids, contrary to expectation. The mechanism of the stable solvation is proposed. The upconversion quantum yields are found to rapidly saturate as the excitation light power increases. An analytical model was developed and compared with the experimental data. It is shown that ionic liquids are not viscous media for the purpose of TTA-based upconversion.

  18. Rational Design of a Lanthanide-Based Complex Featuring Different Single-Molecule Magnets.

    PubMed

    Pointillart, F; Guizouarn, T; Lefeuvre, B; Golhen, S; Cador, O; Ouahab, L

    2015-11-16

    The rational synthesis of the 2-{1-methylpyridine-N-oxide-4,5-[4,5-bis(propylthio)tetrathiafulvalenyl]-1H-benzimidazol-2-yl}pyridine ligand (L) is described. It led to the tetranuclear complex [Dy4(tta)12(L)2] (Dy-Dy2-Dy) after coordination reaction with the precursor Dy(tta)3⋅2 H2O (tta(-) = 2-thenoyltrifluoroacetonate). The X-ray structure of Dy-Dy2-Dy can be described as two terminal mononuclear units bridged by a central antiferromagnetically coupled dinuclear complex. The terminal N2O6 and central O8 environments are described as distorted square antiprisms. The ac magnetism measurements revealed a strong out-of-phase signal of the magnetic susceptibility with two distinct sets of data. The high- and low-frequency components were attributed to the two terminal mononuclear single-molecule magnets (SMMs) and the central dinuclear SMM, respectively. A magnetic hysteresis loop was detected at very low temperature. From both structural and magnetic points of view, the tetranuclear SMM Dy-Dy2-Dy is a self-assembly of two known mononuclear SMMs bridged by a known dinuclear SMM. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. The Role of Triplet Exciton Diffusion in Light-Upconverting Polymer Glasses.

    PubMed

    Raišys, Steponas; Kazlauskas, Karolis; Juršėnas, Saulius; Simon, Yoan C

    2016-06-22

    Light upconversion (UC) via triplet-triplet annihilation (TTA) by using noncoherent photoexcitation at subsolar irradiance power densities is extremely attractive, particularly for enhanced solar energy harvesting. Unfortunately, practical TTA-UC application is hampered by low UC efficiency of upconverting polymer glasses, which is commonly attributed to poor exciton diffusion of the triplet excitons across emitter molecules. The present study addresses this issue by systematically evaluating triplet exciton diffusion coefficients and diffusion lengths (LD) in a UC model system based on platinum-octaethylporphyrin-sensitized poly(methyl methacrylate)/diphenylanthracene (emitter) films as a function of emitter concentration (15-40 wt %). For this evaluation time-resolved photoluminescence bulk-quenching technique followed by Stern-Volmer-type quenching analysis of experimental data was employed. The key finding is that although increasing emitter concentration in the disordered PMMA/DPA/PtOEP films improves triplet exciton diffusion, and thus LD, this does not result in enhanced UC quantum yield. Conversely, improved LD accompanied by the accelerated decay of UC intensity on millisecond time scale degrades TTA-UC performance at high emitter loadings (>25 wt %) and suggests that diffusion-enhanced nonradiative decay of triplet excitons is the major limiting factor.

  20. Associations between fatty acid oxidation, hepatic mitochondrial function, and plasma acylcarnitine levels in mice.

    PubMed

    Bjørndal, Bodil; Alterås, Eva Katrine; Lindquist, Carine; Svardal, Asbjørn; Skorve, Jon; Berge, Rolf K

    2018-01-01

    The 4-thia fatty acid tetradecylthiopropionic acid (TTP) is known to inhibit mitochondrial β-oxidation, and can be used as chemically induced hepatic steatosis-model in rodents, while 3-thia fatty acid tetradecylthioacetic acid (TTA) stimulates fatty acid oxidation through activation of peroxisome proliferator activated receptor alpha (PPARα). We wished to determine how these two compounds affected in vivo respiration and mitochondrial efficiency, with an additional goal to elucidate whether mitochondrial function is reflected in plasma acylcarnitine levels. C57BL/6 mice were divided in 4 groups of 10 mice and fed a control low-fat diet, low-fat diets with 0.4% ( w /w) TTP, 0.4% TTA or a combination of these two fatty acids for three weeks ( n  = 10). At sacrifice, β-oxidation and oxidative phosphorylation (OXPHOS) capacity was analysed in fresh liver samples. Hepatic mitochondria were studied using transmission electron microscopy. Lipid classes were measured in plasma, heart and liver, acylcarnitines were measured in plasma, and gene expression was measured in liver. The TTP diet resulted in hepatic lipid accumulation, plasma L-carnitine and acetylcarnitine depletion and elevated palmitoylcarnitine and non-esterified fatty acid levels. No significant lipid accumulation was observed in heart. The TTA supplement resulted in enhanced hepatic β-oxidation, accompanied by an increased level of acetylcarnitine and palmitoylcarnitine in plasma. Analysis of mitochondrial respiration showed that TTP reduced oxidative phosphorylation, while TTA increased the maximum respiratory capacity of the electron transport system. Combined treatment with TTP and TTA resulted in a profound stimulation of genes involved in the PPAR-response and L-carnitine metabolism, and partly prevented triacylglycerol accumulation in the liver concomitant with increased peroxisomal β-oxidation and depletion of plasma acetylcarnitines. Despite an increased number of mitochondria in the liver of TTA + TTP fed mice, the OXPHOS capacity was significantly reduced. This study indicates that fatty acid β-oxidation directly affects mitochondrial respiratory capacity in liver. As plasma acylcarnitines reflected the reduced mitochondrial β-oxidation in TTP-fed mice, they could be useful tools to monitor mitochondrial function. As mitochondrial dysfunction is a major determinant of metabolic disease, this supports their use as plasma markers of cardiovascular risk in humans. Results however indicate that high PPAR activation obscures the interpretation of plasma acylcarnitine levels.

  1. Electronic Warfare Systems Career Ladder, AFSC 456X1A/B.

    DTIC Science & Technology

    1991-04-01

    En .. 𔃾- (AS L o t.. 4 - 0 L. 0 IXtC SL U41 .004- -C . W a 3 2 ) P- C XL x1. C4’ X O b .4 -J L. 0...2 Im 1m 1 AL/HRD/ID 1 1M lm/lh1 ARMY OCCUPATIONAL SURVEY BRANCH 1 CCAF/AYX 1 DEFENSE TECHNICAL INFORMATION CENTER 2 DE1 3 , USAFOMS (KEESLER AFB MS) 1...1 i HQ AFISC/DAP 2 HQ AFLC/DPMAE 3 HQ AFSC/DPAL 3 3 HQ AFSC/TTA 1 1 HQ ATC/DPAE 3 3 HQ ATC/TTOA 2 1 HQ ESC/DPTE 3 3 HQ ESC/TTA 1 1 HQ MAC/DPAT 3 3

  2. Evaluation of Genomic Instability in the Abnormal Prostate

    DTIC Science & Technology

    2007-12-01

    Mehrotra, J., Varde, S., Wang, H., Chiu, H., Vargo, J., Gray , K., Nagle, R.B., Neri, J.R., Mazumder, A. (2007) Prostate 68, 152-60. Appendix A...GSTP-1 Reverse 5’-GCC CCA ATA CTA AAT CAC GAC G-3’ GSTP-1 Probe 5’-6-FAM-CGG TCG ACG TTC GGG GTG TAG CG-6-TAMSp-3’ RassF1A Forward 5’-GCG TTG AAG...GAA CCA AAA CGC TCC CCA T-3’ APC Reverse 5’-TTA TAT GTC GGT TAC GTG CGT TTA TAT-3’ APC Probe 5’-6-FAM-CCC GTC GAA AAC CCG CCG ATT A-6-TAMSp-3

  3. Kinetic Monte Carlo modeling of the efficiency roll-off in a multilayer white organic light-emitting device

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mesta, M.; Coehoorn, R.; Bobbert, P. A.

    2016-03-28

    Triplet-triplet annihilation (TTA) and triplet-polaron quenching (TPQ) in organic light-emitting devices (OLEDs) lead to a roll-off of the internal quantum efficiency (IQE) with increasing current density J. We employ a kinetic Monte Carlo modeling study to analyze the measured IQE and color balance as a function of J in a multilayer hybrid white OLED that combines fluorescent blue with phosphorescent green and red emission. We investigate two models for TTA and TPQ involving the phosphorescent green and red emitters: short-range nearest-neighbor quenching and long-range Förster-type quenching. Short-range quenching predicts roll-off to occur at much higher J than measured. Taking long-rangemore » quenching with Förster radii for TTA and TPQ equal to twice the Förster radii for exciton transfer leads to a fair description of the measured IQE-J curve, with the major contribution to the roll-off coming from TPQ. The measured decrease of the ratio of phosphorescent to fluorescent component of the emitted light with increasing J is correctly predicted. A proper description of the J-dependence of the ratio of red and green phosphorescent emission needs further model refinements.« less

  4. Return to duty and disability after combat-related hindfoot injury.

    PubMed

    Sheean, Andrew J; Krueger, Chad A; Hsu, Joseph R

    2014-11-01

    To characterize the return-to-duty (RTD) rates and disability outcomes for soldiers who sustained combat-related hindfoot injuries that were treated with either reconstruction or transtibial amputation (TTA). Retrospective cohort series. Tertiary trauma center. All patients treated for combat-related hindfoot injuries between May 2005 and July 2011. TTA or hindfoot reconstruction/ankle fusion. Age, RTD rate, combined disability, and associated disabling conditions. One hundred twenty-two patients underwent treatment for combat-related hindfoot injuries. Fifty-seven patients were treated with amputation, and 65 patients were treated with hindfoot reconstruction or ankle fusion. The overall RTD rate was 20%. Amputees had a RTD rate of 12%, which was lower than those who had a fusion or hindfoot repair [26% (P < 0.06)]. The disability ratings of amputees were significantly higher than those patients undergoing either ankle fusion or primary hindfoot repair [75% and 62%, respectively (P < 0.006)]. While RTD rates were higher for hindfoot reconstruction or ankle fusion compared with TTA, psychiatric conditions were more common among these patients. Although there were clear differences between both groups, the relationship between true functional outcomes and disability ratings remains unclear and both treatment groups seem to do poorly in terms of returning to active duty. Therapeutic level III. See instructions for authors for a complete description of levels of evidence.

  5. Trauma team activation criteria in managing trauma patients at an emergency room in Thailand.

    PubMed

    Wuthisuthimethawee, P

    2017-02-01

    Trauma team activation (TTA) criteria were first implemented in the Emergency Department (ED) of Songklanagarind Hospital in 2009 to treat severe trauma patients. To determine the efficacy of the TTA criteria on the acute trauma care process in the ED and the 28-day mortality rate. A 1-year prospective cohort study was conducted at the ED. Trauma patients who were 18 years old and over who met the TTA criteria were enrolled. Demographic data, physiologic parameters, ED length of stay (EDLOS), and the injury severity score (ISS) were recorded. Multiple logistic regression was used to determine the factors affecting 28-day mortality. Institutional review board approval was obtained from the Prince of Songkla University. A total of 80 patients (74 male and 6 female) were eligible with a mean age of 34.3 years old. Shock, penetrating torso injury, and pulse rate >120 beats per minute were the three most common criteria for trauma team consultation. At the ED, 9 patients (11.3 %) were non-survivors, 30 patients (37.5 %) needed immediate operation, and 41 patients (51.2 %) were admitted. All of the arrest patients died (p < 0.0001). The median time of EDLOS was 85 min: 68 min in the non-survivor group and 120 min in the survivor group (p = 0.028). The median ISS was 21.0 (1-75): 25.0 in the non-survivor group and 17.0 in the survivor group. When compared with pilot data prior to TTA implementation, the median time of EDLOS improved from 184 to 85 min and the 28-day mortality rate decreased from 66.7 to 46.3 %. The high ISS was a predictor of death. The trauma team activation criteria improved acute trauma care in the ED which was demonstrated by the decreased EDLOS and mortality rate. A high ISS is the sole parameter predicting mortality.

  6. Comparison of the boomerang wire vascular access management system versus manual compression alone during percutaneous diagnostic and interventional cardiovascular procedures: The boomerang™ wire vascular access management trial II.

    PubMed

    Goswami, Nilesh J; Smalling, Ronnie G; Sinha, Shantanu; Gammon, Roger S; Ramaiah, Venkatesh G

    2016-01-01

    To evaluate the use of the Boomerang™ Wire as an adjunct to manual compression (MC) in patients requiring diagnostic (Dx) or interventional (Ix) percutaneous procedures. MC remains the standard of care for closure of femoral artery access sites. Adjunctive use of a device to facilitate closure, reduce time to hemostasis (TTH) and ambulation (TTA) without increasing complication rates could reduce costs and hospital resource demands. The Boomerang™ Trial was a prospective, multicenter, randomized, controlled trial comparing use of the Boomerang™ wire, (Cardiva Medical, Sunnyvale, CA) in conjunction with MC versus MC alone to achieve hemostasis in Dx and Ix patients undergoing percutaneous procedures requiring femoral artery access. Endpoints included TTH, TTA, major, and minor access-site related complications. Subjects were randomized 3:1, Boomerang versus MC. No minor or major device-related adverse events were reported. Nondevice related complication rates were 3 (0.9%) in the Boomerang arm (n = 327) and 1 (0.8%) in MC arm (n = 123). Mean TTH for Boomerang vs. MC was 11.2 ± 4.3 vs. 23.2 ± 11 min for Dx (P < 0.0001) and 13.9 ± 5.4 vs. 38.4 ± 57.3 min for Ix patients (P < 0.0001). Mean TTA for Boomerang vs. MC was 3.3 ± 3.0 vs. 4.5 ± 2.0 hr (P < 0.0001)for Dx and 5.4 ± 3.3 vs. 6.8 ± 3.2 hr (P < 0.0001) for Ix patients. Boomerang™ use, in conjunction with MC, was associated with low rates of complications and demonstrated that Boomerang™ as an adjunct to MC can significantly decrease TTH and TTA after both Dx and Ix procedures. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  7. Phase stability of Keplerate-type polyoxomolybdates controlled by added cationic surfactant.

    PubMed

    Fan, Dawei; Hao, Jingcheng

    2009-05-15

    Phase stability of two nanometer-scale Keplerate-type polyoxomolybdates, (NH(4))(42)[Mo(VI)(72)Mo(V)(60)O(372)(CH(3)COO)(30)(H(2)O)(72)]300H(2)O10CH(3)COONH(4) ({Mo(132)}) and Mo(VI)(72)Fe(III)(30)O(252)L(102)ca. 180H(2)O with L=H(2)O/CH(3)COO(-)/Mo(2)O(n-)(8/9) ({Mo(72)Fe(30)}), can be easily achieved by controlling the concentration of a cationic surfactant, tetradecyltrimethylammonium bromide (TTABr), in aqueous solution. Precipitates and floccules were observed when the stoichiometric ratios of rTTA+/{Mo132} and rTTA+/{Mo72Fe30} were 40:1 and 90:1, respectively, which were determined by zeta potential measurements. The surface charge properties and structure morphologies of {Mo(132)} and {Mo(72)Fe(30)} induced by controlling cationic TTABr in aqueous solution were determined by zeta potential measurements and transmission electron microscopy (TEM) observations. {Mo(132)} and {Mo(72)Fe(30)} can self-assemble into supramolecular "Blackberry" structures and exist at compositions less than the stoichiometric ratios of rTTA+/{Mo132} and rTTA+/{Mo72Fe30} in aqueous solution. Above the 1:1 stoichiometric ratio of TTABr/{Mo(132)} or TTABr/{Mo(72)Fe(30)}, the precipitates and floccules dissolve. Dynamic laser light scattering (DLS) measurements clearly demonstrated that the R(h) values have essentially no angular dependence at excess amounts of TTABr, suggesting the presence of spherically symmetric aggregates of {Mo(132)} and {Mo(72)Fe(30)}. Bilayer-like structures in aqueous solution were also demonstrated by TEM images. The interesting phase transition observed in our model systems of {Mo(132)} and {Mo(72)Fe(30)} macroanions with high chemical stability, similar shape, and masses could provide models for the understanding of more complex polyelectrolyte solutions and self-assembled soft magnetic materials and in bioapplications for highly selective adsorbents of proteins with different molecular sizes and charges.

  8. Role of TAF12 in the Increased VDR Activity in Paget’s Disease of Bone

    DTIC Science & Technology

    2013-10-01

    and 5’‐GCC AAA TGC AGT TTA AGC TCT GCT‐3’ (antisense). The gene‐specific primers for mouse b‐actin were 5’‐GGC CGT ACC ACT GGC ATC GTG ATG‐ 3...cycles. The gene‐specific primers for CYP24A1 mRNA were 5’‐CGG GTG GAC CAT TTA CAA CTC GG‐3’ (sense) and 5’‐CTC AAC AGG CTC ATT GTC TGT GG‐3’ (antisense...The gene specific designing primers for b‐actinwere 5’‐ GTG CGT GAC ATC AAA GAG‐3’ (sense) and 5’‐GCC ACA GGA TTC CAT ACC‐3’ (antisense). The

  9. Ecological Risk Assessment of Munitions Compounds on Coral and Coral Reef Health

    DTIC Science & Technology

    2014-01-01

    C308R Porites lobata Maunalua Bay, Oahu, HI K5 TAG GTG GGG AAT CAA ACG GC C307F C309F Porites lobata La Perouse, Maui, HI 3-3 GCT GGC TTA CAG...GGA ATT TTA ACT TCA AGC 24 41.7% 54°C 2.08 Kb this work Porites mtDNA cobR A GAT TCT CTT TGC GCA GTG GCA TAG G 25 52.0% 59°C this work Porites mtDNA...47.6% 52°C 2.14 Kb this work Porites mtDNA nad5(5’)R K CCA ACT GTG CAG ACT TTC CAA CC 23 52.2% 57°C this work References and further reading

  10. Biochemical Characterisation of TSC1 and TSC2 Variants Identified in Patients with Tuberous Sclerosis Complex

    DTIC Science & Technology

    2010-07-01

    G-3¶) and TSC1 reverse (5¶-GCG GGT ACC TTA GCT GTG TTC ATG AGT CTC-3¶). Subsequently, an mCherry tag was inserted N-terminally in pcDNA3.1-TSC1 to...primer pair mCherry forward (5¶-GCG TCT AGA ACC ATG GTG AGC AAG GGC GA-3¶) and mCherry reverse (5¶-GCG GCT AGC CTT GTA CAG CTC GTC CAT GCC-3¶). The...5¶-GAT GAG ATC CGC ACC CTC TGA GAC CAG CTG CTT TTA CTG CAC AAC-3¶; TSC1R692X reverse: 5¶-GTT GTG CAG TAA AAG CAG CTG GTC TCA GAG GGT GCG GAT CTC ATC

  11. Computational design and fabrication of a novel bioresorbable cage for tibial tuberosity advancement application.

    PubMed

    Castilho, Miguel; Rodrigues, Jorge; Vorndran, Elke; Gbureck, Uwe; Quental, Carlos; Folgado, João; Fernandes, Paulo R

    2017-01-01

    Tibial tuberosity advancement (TTA) is a promising method for the treatment of cruciate ligament rupture in dogs that usually implies the implantation of a titanium cage as bone implant. This cage is non-biodegradable and fails in providing adequate implant-bone tissue integration. The objective of this work is to propose a new process chain for designing and manufacturing an alternative biodegradable cage that can fulfill specific patient requirements. A three-dimensional finite element model (3D FEM) of the TTA system was first created to evaluate the mechanical environment at cage domain during different stages of the dog walk. The cage microstructure was then optimized using a topology optimization tool, which addresses the accessed local mechanical requirements, and at same time ensures the maximum permeability to allow nutrient and oxygen supply to the implant core. The designed cage was then biofabricated by a 3D powder printing of tricalcium phosphate cement. This work demonstrates that the combination of a 3D FEM with a topology optimization approach enabled the design of a novel cage for TTA application with tailored permeability and mechanical properties, that can be successfully 3D printed in a biodegradable bioceramic material. These results support the potential of the design optimization strategy and fabrication method to the development of customized and bioresorbable implants for bone repair. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Incidence of complications associated with tibial tuberosity advancement in Boxer dogs.

    PubMed

    de Lima Dantas, Brigite; Sul, Rui; Parkin, Tim; Calvo, Ignacio

    2016-01-01

    To retrospectively review and describe the incidence of complications associated with tibial tuberosity advancement (TTA) surgical procedures in a group of Boxer dogs (n = 36 stifles) and compare the data with a non-Boxer control population (n = 271 stifles). Retrospective analysis of medical records to identify all dogs that underwent TTA surgery due to cranial cruciate ligament disease. These records were categorized into two groups: Boxer dogs and non-Boxer dogs (controls - all other breeds). Of the 307 stifles included, 69 complications were reported in 58 joints. The complication rate differed significantly for Boxer dogs (16/36 stifles) and non-Boxer dogs (42/271 stifles), corresponding to an odds ratio of 5.8 (confidence interval: 1.96-17.02; p-value <0.001). Boxer dogs were more likely to undergo revision surgery and to develop multiple complications. The incidence of tibial tuberosity fractures requiring surgical repair (2/36 versus 1/271) and incisional infections requiring antibiotic treatment (three in each group) was significantly higher in the Boxer group. Boxer dogs had more major and multiple complications after TTA surgery than the control non-Boxer group; these complications included higher rates of revision surgery, tibial tuberosity fractures requiring stabilization, and infection related complications. The pertinence and value of breed-specific recommendations for cranial cruciate ligament disease appears to be a subject worthy of further investigation.

  13. Characterization of Plasmodium falciparum Choline Transporters

    DTIC Science & Technology

    2005-04-01

    ElO PfCTL v.1 transcript El IE2E31E41 E5 E6EE EJ PfCTL v.2 transcript B 1/1 31/11 61/21 91/31 ATG AAT TAC ATC GAG ATG GAA GA CGT GAA TAT AAA CCA CTT...ATA GA GAA GTGBGAT AAT GGA AC AT ATT ATA ATA MT MC MG GM TAT TAT AAC ATG TAT GA AAC AT MT ATA M N Y I E M4 E E R E Y K P L I EK E V D N G N N I B I N N...GGT ATA AAT TAC MT GGG AM ATA TGT GGA AAG GAT CTA CAT AA TAT CCA TAT TTA TAC TTC CCT CTT ACT CCT MA MT CCT MA CCT GA ATA TTA AGT ACC TAT GCT MA TGC YO G

  14. Joint contact forces can be reduced by improving joint moment symmetry in below-knee amputee gait simulations.

    PubMed

    Koelewijn, Anne D; van den Bogert, Antonie J

    2016-09-01

    Despite having a fully functional knee and hip in both legs, asymmetries in joint moments of the knee and hip are often seen in gait of persons with a unilateral transtibial amputation (TTA), possibly resulting in excessive joint loading. We hypothesize that persons with a TTA can walk with more symmetric joint moments at the cost of increased effort or abnormal kinematics. The hypothesis was tested using predictive simulations of gait. Open loop controls of one gait cycle were found by solving an optimization problem that minimizes a combination of walking effort and tracking error in joint angles, ground reaction force and gait cycle duration. A second objective was added to penalize joint moment asymmetry, creating a multi-objective optimization problem. A Pareto front was constructed by changing the weights of the objectives and three solutions were analyzed to study the effect of increasing joint moment symmetry. When the optimization placed more weight on moment symmetry, walking effort increased and kinematics became less normal, confirming the hypothesis. TTA gait improved with a moderate increase in joint moment symmetry. At a small cost of effort and abnormal kinematics, the peak hip extension moment in the intact leg was decreased significantly, and so was the joint contact force in the knee and hip. Additional symmetry required a significant increase in walking effort and the joint contact forces in both hips became significantly higher than in able-bodied gait. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Tibial Tuberosity Anteromedialization for Patellofemoral Chondral Disease: Prognostic Factors.

    PubMed

    Rosso, Federica; Rossi, Roberto; Governale, Giorgio; Marmotti, Antongiulio; Cherubini, Valeria; Cottino, Umberto; Bonasia, Davide Edoardo

    2017-06-01

    Tibial tuberosity anteromedialization (TTA) is a well-established treatment option for patellofemoral chondral disease that is resistant to nonoperative treatment. However, the prognostic factors of this procedure are unknown. To analyze the prognostic factors correlated with the midterm outcomes of TTA for patellofemoral chondral disease and determine the survivorship. Case series; Level of evidence, 4. Indications of TTA for chondral disease included skeletal maturity, age <65 years, 7 points (34.6% of knees) in the multiple regression model was associated with age >45 years (odds ratio [OR], 10.4; 95% CI, 2.0-55.0) and increased femoral anteversion (OR, 7.9; 95% CI, 1.4-44.1). A Kujala score of <80 points (61.5% of knees) was associated with age >45 years (OR, 12.0; 95% CI, 2.6-56.2) and foot pronation (OR, 5.1; 95% CI, 1.3-20.4). Patient satisfaction of <7 of 10 points (32.1% of knees) was associated with positive postoperative patellofemoral crepitus (OR, 3.6; 95% CI, 1.1-11.7). The Kaplan-Meier survivorship of TTA with dissatisfaction (<5/10 points) as an end point was 94% at 43 months, 88% at 77 months, and 77% at 108 months. Overall, good outcomes and survivorship (77% at 108 months) were obtained in this case series. However, 25.6% of the patients would not undergo the surgery again. Increased age, increased femoral anteversion, foot pronation, and postoperative patellofemoral crepitus were identified as negative prognostic factors.

  16. Novel fluorescence adjustable photonic crystal materials

    NASA Astrophysics Data System (ADS)

    Zhu, Cheng; Liu, Xiaoxia; Ni, Yaru; Fang, Jiaojiao; Fang, Liang; Lu, Chunhua; Xu, Zhongzi

    2017-11-01

    Novel photonic crystal materials (PCMs) with adjustable fluorescence were fabricated by distributing organic fluorescent powders of Yb0.2Er0.4Tm0.4(TTA)3Phen into the opal structures of self-assembled silica photonic crystals (PCs). Via removing the silica solution in a constant speed, PCs with controllable thicknesses and different periodic sizes were obtained on glass slides. Yb0.2Er0.4Tm0.4(TTA)3Phen powders were subsequently distributed into the opal structures. The structures and optical properties of the prepared PCMs were investigated. Finite-difference-time-domain (FDTD) calculation was used to further analyze the electric field distributions in PCs with different periodic sizes while the relation between periodic sizes and fluorescent spectra of PCMs was discussed. The results showed that the emission color of the PCMs under irradiation of 980 nm laser can be easily adjusted from green to blue by increasing the periodic size from 250 to 450 nm.

  17. Light-Harvesting Organic Nanocrystals Capable of Photon Upconversion.

    PubMed

    Li, Li; Zeng, Yi; Yu, Tianjun; Chen, Jinping; Yang, Guoqiang; Li, Yi

    2017-11-23

    Harvesting and converting low energy photons into higher ones through upconversion have great potential in solar energy conversion. A light-harvesting nanocrystal assembled from 9,10-distyrylanthracene and palladium(II) meso-tetraphenyltetrabenzoporphyrin as the acceptor and the sensitizer, respectively effects red-to-green upconversion under incoherent excitation of low power density. An upconversion quantum yield of 0.29±0.02 % is obtained upon excitation with 640 nm laser of 120 mW cm -2 . The well-organized packing of acceptor molecules with aggregation-induced emission in the nanocrystals dramatically reduces the nonradiative decay of the excited acceptor, benefits the triplet-triplet annihilation (TTA) upconversion and guides the consequent upconverted emission. This work provides a straightforward strategy to develop light-harvesting nanocrystals based on TTA upconversion, which is attractive for energy conversion and photonic applications. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Magnetic properties of Mn{sub 1.9}Cu{sub 0.1}Sb under high pressure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matsumoto, Yoshihiro; Hiroi, Masahiko; Mitsui, Yoshifuru

    2016-08-26

    Magnetization measurements were carried out for polycrystalline Mn{sub 1.9}Cu{sub 0.1}Sb in magnetic fields up to 5 T in the 10-300 K temperature range under high pressures up to 1 GPa in order to investigate the magnetic properties and the thermal transformation arrest (TTA) phenomenon under high pressures. The spin-reorientation temperature increased from 202 K for 0.1 MPa to 244 K for 1 GPa, whereas the transition temperature from the ferrimagnetic (FRI) to antiferromagnetic (AFM) state did not drastically change at ∼116 K. The magnetic relaxation behavior from the FRI to AFM state was observed in 10 < T ≤ 70more » K, which was analyzed using the Kohlrausch-Williams-Watts model. Obtained results indicated that the TTA phenomenon of Mn{sub 1.9}Cu{sub 0.1}Sb was suppressed by the application of high pressures.« less

  19. Triplet-triplet annihilation photon-upconversion: towards solar energy applications.

    PubMed

    Gray, Victor; Dzebo, Damir; Abrahamsson, Maria; Albinsson, Bo; Moth-Poulsen, Kasper

    2014-06-14

    Solar power production and solar energy storage are important research areas for development of technologies that can facilitate a transition to a future society independent of fossil fuel based energy sources. Devices for direct conversion of solar photons suffer from poor efficiencies due to spectrum losses, which are caused by energy mismatch between the optical absorption of the devices and the broadband irradiation provided by the sun. In this context, photon-upconversion technologies are becoming increasingly interesting since they might offer an efficient way of converting low energy solar energy photons into higher energy photons, ideal for solar power production and solar energy storage. This perspective discusses recent progress in triplet-triplet annihilation (TTA) photon-upconversion systems and devices for solar energy applications. Furthermore, challenges with evaluation of the efficiency of TTA-photon-upconversion systems are discussed and a general approach for evaluation and comparison of existing systems is suggested.

  20. Automatic Control of Gene Expression in Mammalian Cells.

    PubMed

    Fracassi, Chiara; Postiglione, Lorena; Fiore, Gianfranco; di Bernardo, Diego

    2016-04-15

    Automatic control of gene expression in living cells is paramount importance to characterize both endogenous gene regulatory networks and synthetic circuits. In addition, such a technology can be used to maintain the expression of synthetic circuit components in an optimal range in order to ensure reliable performance. Here we present a microfluidics-based method to automatically control gene expression from the tetracycline-inducible promoter in mammalian cells in real time. Our approach is based on the negative-feedback control engineering paradigm. We validated our method in a monoclonal population of cells constitutively expressing a fluorescent reporter protein (d2EYFP) downstream of a minimal CMV promoter with seven tet-responsive operator motifs (CMV-TET). These cells also constitutively express the tetracycline transactivator protein (tTA). In cells grown in standard growth medium, tTA is able to bind the CMV-TET promoter, causing d2EYFP to be maximally expressed. Upon addition of tetracycline to the culture medium, tTA detaches from the CMV-TET promoter, thus preventing d2EYFP expression. We tested two different model-independent control algorithms (relay and proportional-integral (PI)) to force a monoclonal population of cells to express an intermediate level of d2EYFP equal to 50% of its maximum expression level for up to 3500 min. The control input is either tetracycline-rich or standard growth medium. We demonstrated that both the relay and PI controllers can regulate gene expression at the desired level, despite oscillations (dampened in the case of the PI controller) around the chosen set point.

  1. Toxicity evaluation of magnetic hyperthermia induced by remote actuation of magnetic nanoparticles in 3D micrometastasic tumor tissue analogs for triple negative breast cancer.

    PubMed

    Stocke, Nathanael A; Sethi, Pallavi; Jyoti, Amar; Chan, Ryan; Arnold, Susanne M; Hilt, J Zach; Upreti, Meenakshi

    2017-03-01

    Magnetic hyperthermia as a treatment modality is acquiring increased recognition for loco-regional therapy of primary and metastatic lung malignancies by pulmonary delivery of magnetic nanoparticles (MNP). The unique characteristic of magnetic nanoparticles to induce localized hyperthermia in the presence of an alternating magnetic field (AMF) allows for preferential killing of cells at the tumor site. In this study we demonstrate the effect of hyperthermia induced by low and high dose of MNP under the influence of an AMF using 3D tumor tissue analogs (TTA) representing the micrometastatic, perfusion independent stage of triple negative breast cancer (TNBC) that infiltrates the lungs. While application of inhalable magnetic nanocomposite microparticles or magnetic nanocomposites (MnMs) to the micrometastatic TNBC model comprised of TTA generated from cancer and stromal cells, showed no measureable adverse effects in the absence of AMF-exposure, magnetic hyperthermia generated under the influence of an AMF in TTA incubated in a high concentration of MNP (1 mg/mL) caused significant increase in cellular death/damage with mechanical disintegration and release of cell debris indicating the potential of these inhalable composites as a promising approach for thermal treatment of diseased lungs. The novelty and significance of this study lies in the development of methods to evaluate in vitro the application of inhalable composites containing MNPs in thermal therapy using a physiologically relevant metastatic TNBC model representative of the microenvironmental characteristics in secondary lung malignancies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. A general model for estimating lower extremity inertial properties of individuals with transtibial amputation.

    PubMed

    Ferris, Abbie E; Smith, Jeremy D; Heise, Gary D; Hinrichs, Richard N; Martin, Philip E

    2017-03-21

    Lower extremity joint moment magnitudes during swing are dependent on the inertial properties of the prosthesis and residual limb of individuals with transtibial amputation (TTA). Often, intact limb inertial properties (INTACT) are used for prosthetic limb values in an inverse dynamics model even though these values overestimate the amputated limb's inertial properties. The purpose of this study was to use subject-specific (SPECIFIC) measures of prosthesis inertial properties to generate a general model (GENERAL) for estimating TTA prosthesis inertial properties. Subject-specific mass, center of mass, and moment of inertia were determined for the shank and foot segments of the prosthesis (n=11) using an oscillation technique and reaction board. The GENERAL model was derived from the means of the SPECIFIC model. Mass and segment lengths are required GENERAL model inputs. Comparisons of segment inertial properties and joint moments during walking were made using three inertial models (unique sample; n=9): (1) SPECIFIC, (2) GENERAL, and (3) INTACT. Prosthetic shank inertial properties were significantly smaller with the SPECIFIC and GENERAL model than the INTACT model, but the SPECIFIC and GENERAL model did not statistically differ. Peak knee and hip joint moments during swing were significantly smaller for the SPECIFIC and GENERAL model compared with the INTACT model and were not significantly different between SPECIFIC and GENERAL models. When subject-specific measures are unavailable, using the GENERAL model produces a better estimate of prosthetic side inertial properties resulting in more accurate joint moment measurements for individuals with TTA than the INTACT model. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Comparing crack damage evolution in rocks deformed under conventional and true triaxial loading

    NASA Astrophysics Data System (ADS)

    Browning, J.; Meredith, P. G.; Stuart, C.; Healy, D.; Harland, S. R.; Mitchell, T. M.

    2017-12-01

    The vast majority of experimental studies investigate damage evolution using conventional triaxial stress states (σ1 > σ2 = σ3, CTA), whereas in nature the stress state is generally truly triaxial (σ1 > σ2 > σ3, TTA). We present a comparative study of crack damage evolution during CTA vs. TTA stress conditions using results from measurements made on cubic samples of sandstone deformed in three orthogonal directions with independently controlled stress paths. We have measured, simultaneously with stress and strain, changes in wave velocities in the three principal directions, together with acoustic emission (AE) output. Changes in wave velocities are associated with both elastic closure and opening of pre-existing cracks, and the inelastic formation of new cracks. By contrast, AE is associated only with the inelastic growth of new crack damage. The onset of new damage is shown to be a function of differential stress regardless of the magnitude of mean stress. Hence, we show that damage can form due to a decrease in the minimum principal stress, which reduces mean stress but increases the differential stress. We find an approximately fivefold decrease in the number of AE events in the TTA case in comparison to the CTA case. In essence, we create two end-member crack distributions; one displaying cylindrical transverse isotropy and the other planar transverse isotropy. Taken together, the AE data, the velocities and the crack densities indicate that the intermediate principal stress plays a key role in suppressing the total amount of crack growth and concentrating it in planes sub-parallel to the minimum stress. However, the size of individual cracks remains constant. Hence, the differential stress at which rocks fail (i.e. strength) will be significantly higher under TTA stress (where σ2 > σ3) than under CTA stress (where σ2 = σ3). Cyclic loading tests show that while individual stress states are important, the stress path by which these stress states are reached is equally important. Whether the stress state has been `visited' before is key to determining and understanding damage states. Further damage commences only when the previous maximum differential stress is exceeded, regardless of whether this is achieved by increasing the maximum principal stress or by decreasing the minimum principal stress.

  4. Outdoor dynamic subject-specific evaluation of internal stresses in the residual limb: hydraulic energy-stored prosthetic foot compared to conventional energy-stored prosthetic feet.

    PubMed

    Portnoy, Sigal; Kristal, Anat; Gefen, Amit; Siev-Ner, Itzhak

    2012-01-01

    The prosthetic foot plays an important role in propelling, breaking, balancing and supporting body loads while the amputee ambulates on different grounds. It is therefore important to quantify the effect of the prosthetic foot mechanism on biomechanical parameters, in order to prevent pressure ulcers and deep tissue injury. Our aim was to monitor the internal stresses in the residuum of transtibial amputation (TTA) prosthetic-users ambulating on different terrains, which the amputees encounter during their daily activities, i.e. paved floor, grass, ascending and descending stairs and slope. We specifically aimed to compare between the internal stresses in the TTA residuum of amputees ambulating with a novel hydraulic prosthetic foot compared to conventional energy storage and return (ESR) prosthetic feet. Monitoring of internal stresses was accomplished using a portable subject-specific real-time internal stress monitor. We found significant decrease (p<0.01) in peak internal stresses and in the loading rate of the amputated limb, while walking with the hydraulic foot, compared to walking with ESR feet. The loading rate calculated while ambulating with the hydraulic foot was at least three times lower than the loading rate calculated while ambulating with the ESR foot. Although the average decrease in internal stresses was ≈ 2-fold larger when replacing single-toe ESR feet with the hydraulic foot than when replacing split-toed ESR feet with the hydraulic foot, the differences were statistically insignificant. Our findings suggest that using a hydraulic prosthetic foot may protect the distal tibial end of the TTA residuum from high stresses, therefore preventing pressure-related injury and pain. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Effect of the Healthy Schools Program on Prevalence of Overweight and Obesity in California Schools, 2006–2012

    PubMed Central

    Cotterman, Carolyn; Crawford, Pat; Stevelos, JoAnn; Archibald, Abbie

    2015-01-01

    Introduction The Alliance for a Healthier Generation’s Healthy Schools Program (HSP) is a national evidence-based obesity-prevention initiative aimed at providing the schools in greatest need with onsite training and technical assistance (TTA) and consultation with national experts (HSP national advisors) to create sustainable healthy change in schools’ nutrition and physical activity environments. The objective of this study was to evaluate the impact of HSP on the prevalence of overweight and obesity in California schools, from HSP’s inception in 2006 through 2012. Methods We used statewide body mass index (BMI) data collected annually from 5th-, 7th-, and 9th-grade students to determine whether enrolling in the HSP’s onsite intervention reduced the prevalence of overweight and obesity in intervention schools (n = 281) versus propensity-score matched control schools (n = 709) and whether increasing exposure to the program (TTA and contact with HSP national advisors) was associated with reductions in the prevalence of overweight and obesity. Results Analyses showed no difference between HSP schools and control schools in overweight or obesity prevalence. However, program exposure varied widely among participating schools, and each additional contact with TTA or HSP national advisors was associated with a 0.3% decline in overweight and obesity prevalence (P < .05). Conclusion HSP appears to be an important means of supporting schools in reducing obesity. Although participation in HSP alone was not sufficient to improve weight status in California schools, there was a clear dose–response relationship to the program. HSP serves as an effective model for addressing childhood obesity among engaged schools. PMID:25996984

  6. TTaPP: Together Take a Pause and Ponder: A Critical Thinking Tool for Exploring the Public/Private Lives of Patients.

    PubMed

    Kuhnel, Leslie

    2018-01-01

    The broad use of social networking and user-generated content has increased the online footprint of many individuals. A generation of healthcare professionals have grown up with online search activities as part of their everyday lives. Sites like Facebook, Twitter, and Instagram have given the public new ways to share intimate details about their public and private lives and the lives of their friends and families. As a result, careproviders have the ability to find out more about their patients with just the tap of a key or the click of a mouse. This type of online searching for patient information is known as patient-targeted googling or PTG. This article provides an overview of the emergence of PTG, identifies the potential benefits and possible pitfalls of engaging in PTG, and explores current ethical frameworks that guide decisions about PTG. The article describes the development of a critical thinking tool developed by the Behavioral Health Ethics Committee at CHI Health, that can serve as a best-practice model for other hospitals and health systems. Called TTaPP (Together Take a Pause and Ponder), this tool is designed to help healthcare professionals across settings practice collaborative critical thinking skills as they consider the ethical questions of whether or not to engage in PTG. Finally, this article suggests areas for further study, including ways to prompt collaboration and appropriate documentation by maximizing electronic medical records systems, exploring the effectiveness of the TTaPP tool as a way to promote a culture of collaborative critical thinking practices, and the attitudes of patients and the public regarding PTG. Copyright 2018 The Journal of Clinical Ethics. All rights reserved.

  7. Assessment of Fever Advisory Cards (FACs) as an Initiative to Improve Febrile Neutropenia Management in a Regional Cancer Center Emergency Department.

    PubMed

    Kapil, Priyanka; MacMillan, Meghan; Carvalho, Maritza; Lymburner, Patricia; Fung, Ron; Almeida, Bernadette; Van Dorn, Laurie; Enright, Katherine

    2016-09-01

    We aimed to improve the time to antibiotics (TTA) for patients treated with chemotherapy who present to the emergency department (ED) with febrile neutropenia (FN) by using standardized fever advisory cards (FACs). Patients treated with chemotherapy who visited the ED at the Peel Regional Cancer Center in Ontario, Canada, with suspected FN were identified, before (April 2012 to March 2013) and after (October 2013 to March 2014) FAC implementation. The primary outcome of interest was TTA. Additional process measures included Canadian Triage and Acuity Scale score, time to physician assessment, and FAC compliance. Outcomes were analyzed with descriptive statistics and control charts to determine whether the change in primary measures were within statistical control over time. Between the pre-FAC cohort (n = 239) and post-FAC cohort (n = 69), TTA did not change significantly post-FACs (195 v 244 min, P = .09), with monthly averages demonstrating normal variation by statistical process control methodology. The introduction of FACs increased the percentage of patients with correctly assigned Canadian Triage and Acuity Scale scores (87% v 100%) but did not affect time to physician assessment. Compliance with FACs among patients was not ideal, with only 62.5% using them as intended. The distribution of FACs was associated with an improved incidence of correct FN triaging but did not demonstrate a meaningful improvement in the quality of FN management. This may be explained by FAC use among patients not being ideal. Next steps in the continued effort toward high-quality FN care include redesign of FACs, reinforcement of provider and patient education, and ED outreach. Copyright © 2016 by American Society of Clinical Oncology.

  8. Guide for geometric design and operational factors that impact truck use of toll roads.

    DOT National Transportation Integrated Search

    2010-09-01

    Texas has approximately 300 miles of toll roads, predominantly in the three largest and : most congested urban areas of Austin, Dallas, and Houston. The Texas Turnpike Authority : (TTA) Division of the Texas Department of Transportation (TxDOT) and t...

  9. From producer to consumer: greenhouse tomato quality as affected by variety, maturity stage at harvest, transport conditions, and supermarket storage.

    PubMed

    Verheul, Michèl J; Slimestad, Rune; Tjøstheim, Irene Holta

    2015-05-27

    Possible causes for differences in quality traits at the time of buying were studied in two widely different red tomato types. Three maturity stages were harvested from commercial greenhouses and transferred immediately to controlled environments simulating different storage, transport, and supermarket conditions. Results show significant differences in development of color, fruit firmness, contents of soluble solids (SSC), titratable acids (TTA), phenolics, and carotenoids from harvest to sale, as related to postharvest conditions. Fruit firmness, SSC, and TTA of vine-ripened red cherry tomatoes was 30, 55 and 11% higher than for those harvested at breakers and ripened to red. Temperature, light, UVC radiation, or ethylene during 4 days transport affected tomato quality traits, and differences persisted during 3 weeks of supermarket storage. Ethylene exposure gave a 3.7-fold increase in lycopene content in cherry tomatoes, whereas UVC hormesis revealed a 6-fold increase compared with the control. Results can be used to update recommendations concerning optimal handling.

  10. Decreasing luminescence lifetime of evaporating phosphorescent droplets

    NASA Astrophysics Data System (ADS)

    van der Voort, D. D.; Dam, N. J.; Sweep, A. M.; Kunnen, R. P. J.; van Heijst, G. J. F.; Clercx, H. J. H.; van de Water, W.

    2016-12-01

    Laser-induced phosphorescence has been used extensively to study spray dynamics. It is important to understand the influence of droplet evaporation in the interpretation of such measurements, as it increases luminescence quenching. By suspending a single evaporating n-heptane droplet in an acoustic levitator, the properties of lanthanide-complex europium-thenoyltrifluoroacetone-trioctylphosphine oxide (Eu-TTA-TOPO) phosphorescence are determined through high-speed imaging. A decrease was found in the measured phosphorescence decay coefficient (780 → 200 μs) with decreasing droplet volumes (10-9 → 10-11 m3) corresponding to increasing concentrations (10-4 → 10-2 M). This decrease continues up to the point of shell-formation at supersaturated concentrations. The diminished luminescence is shown not to be attributable to triplet-triplet annihilation, quenching between excited triplet-state molecules. Instead, the pure exponential decays found in the measurements show that a non-phosphorescent quencher, such as free TTA/TOPO, can be attributable to this decay. The concentration dependence of the phosphorescence lifetime can therefore be used as a diagnostic of evaporation in sprays.

  11. Efficiency of noncoherent photon upconversion by triplet-triplet annihilation: the C60 plus anthanthrene system and the importance of tuning the triplet energies.

    PubMed

    Sugunan, Sunish K; Greenwald, Chelsea; Paige, Matthew F; Steer, Ronald P

    2013-07-03

    As part of a continuing effort to find noncoherent photon upconversion (NCPU) systems with improved energy conversion efficiencies, the photophysics of the blue emitter, anthanthrene (An), and the fullerene absorber-sensitizer, C60, have been examined by both steady-state and pulsed laser techniques. An is a promising candidate for NCPU by homomolecular triplet-triplet annihilation (TTA) because its triplet state lies ∼800 cm(-1) below the triplet energy of the C60 donor (thereby improving efficiency by reducing back triplet energy transfer), and its fluorescent singlet state lies in near resonance with double its triplet energy (thus minimizing thermal energy losses in the annihilation process). In fluid solution, efficient triplet-triplet donor-acceptor energy transfer is observed, and rate constants for homomolecular TTA in the An acceptor are estimated to approach the diffusion limit. NCPU is also observed in An + C60 in poly(methylmethacrylate) thin films.

  12. The Easily Learned, Easily Remembered Heuristic in Children

    ERIC Educational Resources Information Center

    Koriat, Asher; Ackerman, Rakefet; Lockl, Kathrin; Schneider, Wolfgang

    2009-01-01

    A previous study with adults [Koriat, A. (2008a). "Easy comes, easy goes? The link between learning and remembering and its exploitation in metacognition." "Memory & Cognition," 36, 416-428] established a correlation between learning and remembering: items requiring more trials to acquisition (TTA) were less likely to be recalled than those…

  13. 75 FR 53969 - Office of Community Services: Notice To Award an Expansion Supplement

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-02

    ... related to job creation and new initiatives that target careers in energy efficiency and other...; and (3) collects, develops, and disseminates resources related to job creation and careers related to... through professional consultations and peer assistance sessions; and online toolkit(s). The T/TA CAP will...

  14. A Flirtatious Dalliance with Technologists?

    ERIC Educational Resources Information Center

    Walker, John

    2010-01-01

    This article discusses a new project that aims to encapsulate all the key features of the new Curriculum for Excellence. Her Majesty's Inspectorate of Education (HMIE) funding was secured to support this emergent joint ASE/Technical Teachers' Association (TTA) initiative, with Learning and Teaching Scotland (LTS) and Determined to Succeed (DtS)…

  15. 78 FR 25292 - Announcement of Funding Awards; Office of Native American Programs Training and Technical...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-30

    ... Awards; Office of Native American Programs Training and Technical Assistance; Fiscal Year 2012 AGENCY... (NOFA) for the Office of Native American Programs Training and Technical Assistance (ONAP T&TA). This... nonprofit organizations, as well as for-profit entities to provide Training & Technical Assistance to the...

  16. GRAS notice 733 for Purified steviol glycosides part 2

    Center for Food Safety and Applied Nutrition (CFSAN)

    ... d()..to. +.'LSl. ct ~ttJ!~~: D : \\ CH . EM32\\ l\\~ATA\\2 J l 6 ~ 09-~~;:1CG002;.o , 'r'\\CVV'I naa~~ .. L' t~ tw~ ~i. i..i./J(ti-. • "'t. c:i.tta.. P.«f pe4t. (J.~" ...

  17. Career-Oriented Performance Tasks: Effects on Students' Interest in Chemistry

    ERIC Educational Resources Information Center

    Espinosa, Allen A.; Monterola, Sheryl Lyn C.; Punzalan, Amelia E.

    2013-01-01

    The study was conducted to assess the effectiveness of Career-Oriented Performance Task (COPT) approach against the traditional teaching approach (TTA) in enhancing students' interest in Chemistry. Specifically, it sought to find out if students exposed to COPT have higher interest in Chemistry than those students exposed to the traditional…

  18. 77 FR 34354 - Notice Inviting Informal Public Comment on Training and Technical Assistance and Disability...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-11

    ... and Technical Assistance and Disability Inclusion Programming AGENCY: Corporation for National and... implementation of a unified training and technical assistance (TTA) strategy and disability inclusion programming... to CNCS as we plan and prepare for this work. We will accept comments in writing, as described below...

  19. Improving Photovoltaic Performance of a Fused-Ring Azepinedione Copolymer via a D-A-A Design.

    PubMed

    Zhang, Honghong; Li, Ting; Xiao, Zuo; Lei, Zhongli; Ding, Liming

    2018-04-01

    Two conjugated copolymer donors, PTTABDT and PBTTABDT, based on a fused-ring azepinedione acceptor unit, 5-(2-octyldodecyl)-4H-thieno[2',3':4,5]thieno[3,2-c]thieno[2',3':4,5]thieno[2,3-e]azepine-4,6(5H)-dione (TTA), are prepared. PTTABDT possesses a conventional donor-acceptor (D-A) structure with one TTA in the repeat unit, while PBTTABDT has a D-A-A structure with two TTAs in the repeat unit. Compared with PTTABDT, PBTTABDT shows a deeper highest occupied molecular orbital (HOMO) level, a narrower bandgap, and a higher hole mobility, and exhibits better performance in bulk heterojunction solar cells. Power conversion efficiencies of 6.18% and 7.81% are achieved from PTTABDT:PC 71 BM and PBTTABDT:PC 71 BM solar cells, respectively. The higher performance of PBTTABDT:PC 71 BM solar cells results from the enhanced open-circuit voltage (V oc ) and short-circuit current density (  J sc ). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. A facile access to new diazepines derivatives: Spectral characterization and crystal structures of 7-(thiophene-2-yl)-5-(trifluoromethyl)-2,3-dihydro-1H-1,4-diazepine and 2-thiophene-4-trifluoromethyl-1,5-benzodiazepine

    NASA Astrophysics Data System (ADS)

    Ahumada, Guillermo; Carrillo, David; Manzur, Carolina; Fuentealba, Mauricio; Roisnel, Thierry; Hamon, Jean-René

    2016-12-01

    The one-pot double condensation reaction of 2-thenoyltrifluoroacetone (2-TTA) with ethylendiamine or o-phenylenediamine, in a 2:1 stoichiometric molar ratio, leads to the formation of 7-(thiophene-2-yl)-5-(trifluoromethyl)-2,3-dihydro-1H-1,4-diazepine 2 and 2-thiophene-4-trifluoromethyl-1,5-benzodiazepine 3, that were isolated in 56 and 53% yields, respectively. The bis(trifluoroacetamide)ethylene derivative 1 was also isolated in 32% yield as a side-product in the reaction of 2-TTA and ethylenediamine. Compounds 1-3 were fully characterized by elemental analysis, FT-IR and multinuclear (1H, 13C and 19F) NMR spectroscopy. In addition, their molecular identities and geometries have been authenticated by single-crystal X-ray diffraction analysis. The spectroscopic and structural data confirm that the 1,4-diazepine 2 and the 1,5-benzodiazepine 3 exist in the imine-enamine and diimine tautomeric forms, respectively, both in solution and in the solid-state.

  1. Photocatalytic Water-Splitting Enhancement by Sub-Bandgap Photon Harvesting.

    PubMed

    Monguzzi, Angelo; Oertel, Amadeus; Braga, Daniele; Riedinger, Andreas; Kim, David K; Knüsel, Philippe N; Bianchi, Alberto; Mauri, Michele; Simonutti, Roberto; Norris, David J; Meinardi, Francesco

    2017-11-22

    Upconversion is a photon-management process especially suited to water-splitting cells that exploit wide-bandgap photocatalysts. Currently, such catalysts cannot utilize 95% of the available solar photons. We demonstrate here that the energy-conversion yield for a standard photocatalytic water-splitting device can be enhanced under solar irradiance by using a low-power upconversion system that recovers part of the unutilized incident sub-bandgap photons. The upconverter is based on a sensitized triplet-triplet annihilation mechanism (sTTA-UC) obtained in a dye-doped elastomer and boosted by a fluorescent nanocrystal/polymer composite that allows for broadband light harvesting. The complementary and tailored optical properties of these materials enable efficient upconversion at subsolar irradiance, allowing the realization of the first prototype water-splitting cell assisted by solid-state upconversion. In our proof-of concept device the increase of the performance is 3.5%, which grows to 6.3% if concentrated sunlight (10 sun) is used. Our experiments show how the sTTA-UC materials can be successfully implemented in technologically relevant devices while matching the strict requirements of clean-energy production.

  2. PubMed Central

    Presutti, L.; Bonali, M.; Marchioni, D.; Pavesi, G.; Feletti, A.; Alicandri-Ciufelli, M.

    2017-01-01

    SUMMARY The aim of this paper is to describe and evaluate the feasibility of an expanded endoscopic transcanal transpromotorial approach (ExpTTA) to the internal auditory canal and the cerebellopontine angle. To this end, we performed a cadaveric dissection study in September 2015. In total, 2 heads (4 sides) were dissected focusing on anatomical landmarks and surgical feasibility. Data from dissections were reviewed and analysed for further consideration. In all 4 sides of the cadavers the procedure was feasible. In all cadavers, it was necessary to extensively drill the temporo-mandibular joint and to calibrate the external ear canal to allow adequate room to manoeuver the instruments and optics and to comfortably access the cerebellopontine angle. In addition, thorough skeletonisation of the carotid artery and the jugular bulb were necessary for the same purpose. In conclusion, ExpTTA appeared to be successful to access the internal auditory canal and cerebellopontine angle region. Potential extensive and routine application of this type of approach in lateral skull base surgery will depend on the development of technology and surgical refinements and on the diffusion of skull base endoscopic skills among otolaryngologists and neurosurgical community. PMID:28516966

  3. Donor-Acceptor-Collector Ternary Crystalline Films for Efficient Solid-State Photon Upconversion.

    PubMed

    Ogawa, Taku; Hosoyamada, Masanori; Yurash, Brett; Nguyen, Thuc-Quyen; Yanai, Nobuhiro; Kimizuka, Nobuo

    2018-06-25

    It is pivotal to achieve efficient triplet-triplet annihilation based photon upconversion (TTA-UC) in the solid-state for enhancing potentials of renewable energy production devices. However, the UC efficiency of solid materials is largely limited by low fluorescence quantum yields that originate from the aggregation of TTA-UC chromophores, and also by severe back energy transfer from the acceptor singlet state to the singlet state of the triplet donor in the condensed state. In this work, to overcome these issues, we introduce a highly fluorescent singlet energy collector as the third component of donor-doped acceptor crystalline films, in which dual energy migration, i.e., triplet energy migration for TTA-UC and succeeding singlet energy migration for transferring energy to a collector, takes place. To demonstrate this scheme, a highly fluorescent singlet energy collector was added as the third component of donor-doped acceptor crystalline films. An anthracene-based acceptor containing alkyl chains and a carboxylic moiety is mixed with the triplet donor Pt(II) octaethylporphyrin (PtOEP) and the energy collector 2,5,8,11-tetra- tert-butylperylene (TTBP) in solution, and spin-coating of the mixed solution gives acceptor films of nanofibrous crystals homogeneously doped with PtOEP and TTBP. Interestingly, delocalized singlet excitons in acceptor crystals are found to diffuse effectively over the distance of ~37 nm. Thanks to this high diffusivity, only 0.5 mol% of doped TTBP can harvest most of the singlet excitons, which successfully doubles the solid-state fluorescent quantum yield of acceptor/TTBP blend films to 76%. Furthermore, since the donor PtOEP and the collector TTBP are separately isolated in the nanofibrous acceptor crystals, the singlet back energy transfer from the collector to the donor is effectively avoided. Such efficient singlet energy collection and inhibited back energy transfer processes result in a large increase of UC efficiency up to 9.0%, offering rational design principles towards ultimately efficient solid-state upconverters.

  4. Regulated expression of the rat recombinant P2X(3) receptor in stably transfected CHO-K1 tTA cells.

    PubMed

    Lachnit, W G; Oglesby, I B; Gever, J R; Gever, M; Huang, C; Li, X C; Jin, H; McGivern, J G; Ford, A P

    2000-07-03

    In this report, the regulatable expression by tetracycline of the rat recombinant P2X(3) receptor in stably transfected Chinese hamster ovary (CHO-K1) expressing the tetracycline-controlled transactivator (tTA) is described. cDNA encoding the rat P2X(3)-receptor was subcloned into pTRE (a tetracycline-repressible expression vector) which was used to transfect stably CHO-K1 tTA cells. Using whole cell patch clamp techniques, 100 microM ATP evoked inward currents of 2.9+/-1.6 nA in transfected cells grown in the absence of tetracycline (tet-). The P2X(3) receptor protein was detectable by immunoblot as early as 24 h and protein expression levels continued to increase as much as 192 h following activation of tTA by the removal of the antibiotic. Saturation binding isotherms using [35S]ATP gamma S yielded a pK(d) of 8.2+/-0.1 and a B(max) of 31.9+/-3.5 pmol/mg protein in tet- cell membranes and a pK(d) of 8.1+/-0.1 and a B(max) of 5.8+/-0.8 pmol/mg protein in tet+ cell membranes. The agonist ligands 2MeSATP and alpha beta MeATP displaced the binding of [35S]ATP gamma S in tet- cell membranes with very high affinity, yielding pIC(50) values of 9.4+/-0.2 and 7.5+/-0. 2, respectively. In tet+ cell membrane, displacement of [35S]ATP gamma S by 2MeSATP and alpha beta MeATP was of much lower affinity (pIC(50) values of 7.8 and 6.2, respectively). ATP, ADP and UTP showed similar displacement of [35S]ATP gamma S binding in tet- and tet+ cell membranes. In other experiments, cytosolic Ca(2+) was monitored using the fluorescent indicator, fluo-3. Increases in cytosolic Ca(2+) were elicited by 100 nM alpha beta MeATP in tet- cells while no increases in cytosolic Ca(2+) were detected below 100 microM alpha beta MeATP in either tet+ cells or untransfected cells. These calcium responses to alpha beta MeATP had a pEC(50) of 6.7 and were transient, returning to baseline within 120 s. Suramin produced concentration-dependent, parallel, dextral shifts of E/[A] curves to alpha beta MeATP yielding a pK(B) of 5.6. PPADS produced non-parallel, dextral shifts of E/[A] curves to alpha beta MeATP which were insurmountable. These results show for the first time, expression of a functional, homomeric recombinant rat P2X(3) receptor which is under regulated expression in a stably transfected mammalian cell line.

  5. 78 FR 55057 - Authority To Manufacture Carbon Fiber for the U.S. Market Not Approved; Foreign-Trade Subzone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-09

    ... behalf of Toho Tenax America, Inc. (TTA), to manufacture carbon fiber under zone procedures for the U.S... approve the application requesting authority to manufacture carbon fiber for the U.S. market under zone... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Order No. 1914] Authority To Manufacture Carbon...

  6. Diatomaceous Fungal and Bacterial Building Blocks for Material Synthesis

    DTIC Science & Technology

    2008-04-08

    Thalassiosira-templated metallic microshells. Thalassiosira, only 1mM rhodamine 6G (d) lmM, (e) I piM ,(f 100 nM R6G. 4 concentrations gave detectable...hybridized with a 27-mer 7 oligonucleotide containing a 7-mer TAG GAA TAG TTA TA AT OTT ATT AGO complementary region 2, which produces TAIOATCCTTA TACAATAATCC

  7. Molecular Genetic Studies of Bone Mechanical Strain and of Pedigrees with Very High Bone Density

    DTIC Science & Technology

    2009-11-01

    mice. We used Cre-recombinase primer (F- TTA GCA CCA CGG CAG CAG GAG GTT and R-CAG GCC AGA TCT CCT GTG CAG CAT) and loxp primer (Primer 1, AGT GAT...Leprdb heterozygotes during breeding. Three types of littermates are produced from breeding these heterozygotes: the misty gray homozygote (m +/m +), the

  8. Postharvest conservation of the tuberous roots of Pachyrhizus Ahipa (Wedd) Parodi.

    PubMed

    Mussury, Rosilda M; Scalon, Silvana P Q; Silva, Magaiver A; Silva, Tatiane F; Gomes, Hellen; Gassi, Rosimeire

    2013-01-01

    This paper aimed to evaluate the effects of storage periods on the conservation of Pachyrhizus ahipa roots at different temperatures and packaging materials. The roots were harvested, washed, packed in PVC, plastic bags, without wrappings (control) and stored in polystyrene trays in refrigerators, or cold chambers, or at room temperature. Total titratable acidity (TTA), total soluble solids (TSS), pH, as well as their ash, lipid, total carbohydrate and protein (dry basis) contents were analyzed. The lowest loss of root fresh weight was observed in the cold chamber and plastic bags. The TTA remained higher among roots stored in the cold chamber and in PVC packaging. The lowest TSS contents were observed for roots stored in the cold chamber, and these did not vary among the packing materials. The average carbohydrate content percentage for all treatments was 84.9%. The percentage of lipids was highest in roots stored at room temperature while protein and ash contents were highest in roots under refrigeration. The best storage conditions for roots are plastic bags packaging in a cold chamber, with the roots retaining appropriate quality for commercialization for up to 30 days.

  9. Cloning and Characterization of an Alpha-amylase Gene from the Hyperthermophilic Archaeon Thermococcus Thioreducens

    NASA Technical Reports Server (NTRS)

    Bernhardsdotter, Eva C. M. J.; Pusey, Marc L.; Ng, Joseph D.; Garriott, Owen K.

    2004-01-01

    The gene encoding an extracellular a-amylase, TTA, from the hyperthermophilic archaeon Thermococcus thioreducens was cloned and expressed in Escherichia coli. Primary structural analysis revealed high similarity with other a-amylases from the Thermococcus and Pyrococcus genera, as well as the four highly conserved regions typical for a-amylases. The 1374 bp gene encodes a protein of 457 amino acids, of which 435 constitute the mature protein preceded by a 22 amino acid signal peptide. The molecular weight of the purified recombinant enzyme was estimated to be 43 kDa by denaturing gel electrophoresis. Maximal enzymatic activity of recombinant TTA was observed at 90 C and pH 5.5 in the absence of exogenous Ca(2+), and the enzyme was considerably stable even after incubation at 90 C for 2 hours. The thermostability at 90 and 102 C was enhanced in the presence of 5 mM Ca(2+). The extraordinarily high specific activity (about 7.4 x 10(exp 3) U/mg protein at 90 C, pH 5.5 with soluble starch as substrate) together with its low pH optimum makes this enzyme an interesting candidate for starch processing applications.

  10. Cloning and Characterization of an alpha-amylase Gene from the Hyperthermophilic Archaeon Thermococcus Thioreducens

    NASA Technical Reports Server (NTRS)

    Bernhardsdotter, Eva C. M. J.; Pusey, Mark L.; Ng, Joseph D.; Garriott, Owen K.

    2004-01-01

    The gene encoding an extracellular alpha-amylase, TTA, from the hyperthermophilic archaeon Thermococcus thioreducens was cloned and expressed in Escherichia coli. Primary structural analysis revealed high similarity with other a-amylases from the Thermococcus and Pyrococcus genera, as well as the four highly conserved regions typical for a-amylases. The 1374 bp gene encodes a protein of 457 amino acids, of which 435 constitute the mature protein preceded by a 22 amino acid signal peptide. The molecular weight of the purified recombinant enzyme was estimated to be 43 kDa by denaturing gel electrophoresis. Maximal enzymatic activity of recombinant TTA was observed at 90 C and pH 5.5 in the absence of exogenous Ca(2+), and the enzyme was considerably stable even after incubation at 90 C for 2 hours. The thermostability at 90 and 102 C was enhanced in the presence of 5 mM Ca(2+). The extraordinarily high specific activity (about 7.4 x 10(exp 3) U/mg protein at 90 C, pH 5.5 with soluble starch as substrate) together with its low pH optimum makes this enzyme an interesting candidate for starch processing applications.

  11. International Space Station ECLSS Technical Task Agreement Summary Report

    NASA Technical Reports Server (NTRS)

    Ray, C. D. (Compiler); Salyer, B. H. (Compiler)

    1999-01-01

    This Technical Memorandum provides a summary of current work accomplished under Technical Task Agreement (TTA) by the Marshall Space Flight Center (MSFC) regarding the International Space Station (ISS) Environmental Control and Life Support System (ECLSS). Current activities include ECLSS component design and development, computer model development, subsystem/integrated system testing, life testing, and general test support provided to the ISS program. Under ECLSS design, MSFC was responsible for the six major ECLSS functions, specifications and standard, component design and development, and was the architectural control agent for the ISS ECLSS. MSFC was responsible for ECLSS analytical model development. In-house subsystem and system level analysis and testing were conducted in support of the design process, including testing air revitalization, water reclamation and management hardware, and certain nonregenerative systems. The activities described herein were approved in task agreements between MSFC and NASA Headquarters Space Station Program Management Office and their prime contractor for the ISS, Boeing. These MSFC activities are in line to the designing, development, testing, and flight of ECLSS equipment planned by Boeing. MSFC's unique capabilities for performing integrated systems testing and analyses, and its ability to perform some tasks cheaper and faster to support ISS program needs, are the basis for the TTA activities.

  12. Biomechanics of the ankle-foot system during stair ambulation: implications for design of advanced ankle-foot prostheses.

    PubMed

    Sinitski, Emily H; Hansen, Andrew H; Wilken, Jason M

    2012-02-02

    Unilateral lower limb prosthesis users display temporal, kinematic, and kinetic asymmetries between limbs while ascending and descending stairs. These asymmetries are due, in part, to the inability of current prosthetic devices to effectively mimic normal ankle function. The purpose of this study was to provide a comprehensive set of biomechanical data for able-bodied and unilateral transtibial amputee (TTA) ankle-foot systems for level-ground (LG), stair ascent (SA), and stair descent (SD), and to characterize deviations from normal performance associated with prosthesis use. Ankle joint kinematics, kinetics, torque-angle curves, and effective shapes were calculated for twelve able-bodied individuals and twelve individuals with TTA. The data from this study demonstrated the prosthetic limb can more effectively mimic the range of motion and power output of a normal ankle-foot during LG compared to SA and SD. There were larger differences between the prosthetic and able-bodied limbs during SA and SD, most evident in the torque-angle curves and effective shapes. These data can be used by persons designing ankle-foot prostheses and provide comparative data for assessment of future ankle-foot prosthesis designs. Published by Elsevier Ltd.

  13. Effects of selected lactic acid bacteria on the characteristics of amaranth sourdough.

    PubMed

    Jekle, Mario; Houben, Andreas; Mitzscherling, Martin; Becker, Thomas

    2010-10-01

    As the processing of amaranth in baked goods is challenging, the use of sourdough fermentation is a promising possibility to exploit the advantages of this raw material. In this study the fermentation properties of Lactobacillus plantarum, Lactobacillus paralimentarius and Lactobacillus helveticus in amaranth-based sourdough were examined in order to validate them as starter cultures. pH, total titratable acidity (TTA) and lactic/acetic acid ratio of the sourdough and sensory properties of the resulting wheat bread were evaluated using fermentation temperatures of 30 and 35 °C. While fermentation pH, TTA and lactic acid concentration showed small variations with the use of L. plantarum and L. paralimentarius, L. helveticus reached the most intensive acidification after initial adaptation to the substrate. Acetic acid production was independent of lactic acid metabolism. Furthermore, the lactic/acetic acid ratio exceeded recommendation by 10-35 times (fermentation quotient 25-82). Sensory evaluation showed no significant differences between the two fermentation temperatures but differences among the three micro-organisms. The results provide relevant information on the fermentation properties required of a customised starter for amaranth flour. Copyright © 2010 Society of Chemical Industry.

  14. Genomic Instability and Breast Cancer

    DTIC Science & Technology

    2007-10-01

    transfected with control or RAP80 siRNAs were exposed to 0 or 4 grays (Gy) of IR. Cells were incubated for 1 hour before fixation and subjected to staining...similarly using primers 5’ AGA CAG AGC AAT CCA GTG AGT CTT TGA GGT GTA ACG TGG AGC CAG TAG 3’ and 5’ ACT GGC TCC ACG TTA CAC CTC AAA GAC TCA CTG GAT TGC

  15. Long-lived room temperature deep-red/near-IR emissive intraligand triplet excited state (3IL) of naphthalimide in cyclometalated platinum(II) complexes and its application in upconversion.

    PubMed

    Wu, Wenting; Guo, Huimin; Wu, Wanhua; Ji, Shaomin; Zhao, Jianzhang

    2011-11-21

    [C(^)NPt(acac)] (C(^)N = cyclometalating ligand; acac = acetylacetonato) complexes in which the naphthalimide (NI) moiety is directly cyclometalated (NI as the C donor of the C-Pt bond) were synthesized. With 4-pyrazolylnaphthalimide, isomers with five-membered (Pt-2) and six-membered (Pt-3) chelate rings were obtained. With 4-pyridinylnaphthalimide, only the complex with a five-membered chelate ring (Pt-4) was isolated. A model complex with 1-phenylpyrazole as the C(^)N ligand was prepared (Pt-1). Strong absorption of visible light (ε = 21,900 M(-1) cm(-1) at 443 nm for Pt-3) and room temperature (RT) phosphorescence at 630 nm (Pt-2 and Pt-3) or 674 nm (Pt-4) were observed. Long-lived phosphorescences were observed for Pt-2 (τ(P) = 12.8 μs) and Pt-3 (τ(P) = 61.9 μs). Pt-1 is nonphosphorescent at RT in solution because of the acac-localized T(1) excited state [based on density functional theory (DFT) calculations and spin density analysis], but a structured emission band centered at 415 nm was observed at 77 K. Time-resolved transient absorption spectra and spin density analysis indicated a NI-localized intraligand triplet excited state ((3)IL) for complexes Pt-2, Pt-3, and Pt-4. DFT calculations on the transient absorption spectra (T(1) → T(n) transitions, n > 1) also support the (3)IL assignment of the T(1) excited states of Pt-2, Pt-3, and Pt-4. The complexes were used as triplet sensitizers for triplet-triplet-annihilation (TTA) based upconversion, and the results show that Pt-3 is an efficient sensitizer with an upconversion quantum yield of up to 14.1%, despite its low phosphorescence quantum yield of 5.2%. Thus, we propose that the sensitizer molecules at the triplet excited state that are otherwise nonphosphorescent were involved in the TTA upconversion process, indicating that weakly phosphorescent or nonphosphorescent transition-metal complexes can be used as triplet sensitizers for TTA upconversion.

  16. Exciton Dynamics in Alternative Solar Cell Materials: Polymers, Nanocrystals, and Small Molecules

    NASA Astrophysics Data System (ADS)

    Pundsack, Thomas J.

    To keep fossil fuel usage in 2040 even with 2010 usage, 50% of global energy will need to come from alternative sources such as solar cells. While the photovoltaic market is currently dominated by crystalline silicon, there are many low-cost solar cell materials such as conjugated polymers, semiconductor nanocrystals, and organic small molecules which could compete with fossil fuels. To create cost-competitive devices, understanding the excited state dynamics of these materials is necessary. The first section of this thesis looks at aggregation in poly(3-hexylthiophene) (P3HT) which is commonly used in organic photovoltaics. The amount of aggregation in P3HT thin films was controlled by using a mixture of regioregular and regiorandom P3HT. Even with few aggregates present, excited states were found to transfer from amorphous to aggregate domains in <50 fs which could indicate efficient long-range energy transfer. To further study P3HT aggregation, a triblock consisting of two P3HT chains with a coil polymer between them was investigated. By changing solvents, aggregation was induced in a stable and reversible manner allowing for spectroscopic studies of P3HT aggregates in solution. The polarity of the solvent was adjusted, and no change in excited state dynamics was observed implying the excited state has little charge-transfer character. Next, the conduction band density of states for copper zinc tin sulfide nanocrystals (CZTS NCs) was measured using pump-probe spectroscopy and found to be in agreement with theoretical results. The density of states shifted and dilated for smaller NCs indicative of quantum confinement. The excited state lifetime was found to be short (<20 ps) and independent of NC size which could limit the efficiency of CZTS photovoltaic devices. Finally, triplet-triplet annihilation (TTA) was studied in platinum octaethylporphyrin (PtOEP) thin films. By analyzing pump-probe spectra, the product of TTA in PtOEP thin films was assigned to a long-lived metal-centered state. To elucidate the mechanism of TTA, the annihilation dynamics were modeled using second order kinetics as well as Forster and Dexter energy transfer. Dexter energy transfer provided the best fits and the most reasonable fitting parameters.

  17. Improved analysis of transient temperature data from permanent down-hole gauges (PDGs)

    NASA Astrophysics Data System (ADS)

    Zhang, Yiqun; Zheng, Shiyi; Wang, Qi

    2017-08-01

    With the installation of permanent down-hole gauges (PDGs) during oil field development, large volumes of high resolution and continuous down-hole information are obtainable. The interpretation of these real-time temperature and pressure data can optimize well performance, provide information about the reservoir and continuously calibrate the reservoir model. Although the dynamic temperature data have been interpreted in practice to predict flow profiling and provide characteristic information of the reservoir, almost all of the approaches rely on established non-isothermal models which depend on thermodynamic parameters. Another problem comes from the temperature transient analysis (TTA), which is underutilized compared with pressure transient analysis (PTA). In this study, several model-independent methods of TTA were performed. The entire set of PDG data consists of many flow events. By utilizing the wavelet transform, the exact points of flow-rate changes can be located. The flow regime changes, for example, from early time linear flow to later time pseudo-radial flow, among every transient period with constant flow-rate. For the early time region (ETR) that is caused by flow-rate change operations, the TTA, along with the PTA can greatly reduce the uncertainties in flow regime diagnosis. Then, the temperature variations during ETR were examined to infer the true reservoir temperature history, and the relationships between the wavelet detailed coefficients and the flow-rate changes were analysed. For the scenarios with constant reservoir-well parameters, the detailed flow-rate history can be generated by calculating the coefficient of relationship in advance. For later times, the flow regime changes to pseudo-radial flow. An analytical solution was introduced to describe the sand-face temperature. The formation parameters, such as permeability and skin factor, were estimated with the previously calculated flow-rate. It is necessary to analyse temperature variation to overcome data limitation problems when information from other down-hole tools (e.g. expensive but unstable flow meters) is insufficient. This study shows the success in wellbore storage regime diagnosis, flow-rate history reconstruction, and formation parameters estimation using transient temperature data.

  18. Role of Setbp1 in Myeloid Leukemia Development

    DTIC Science & Technology

    2014-09-05

    CTC ACT GTG GAG ACG ATT C 3’ 5’ TTC TTA TCC AGC ACA CCA AGC TT 3’ Hoxa9 5’ TGT CTC CTC TCC CCC AAA CC 3’ 5’ GAG ATG AGG CCT GGG ATTTAG A 3’ Hoxa10...highlighted in yellow and noncoding exons in gray . Arrows indicate transcription start sites. The location and orientation of viral integrations are

  19. Photo-reactive charge trapping memory based on lanthanide complex.

    PubMed

    Zhuang, Jiaqing; Lo, Wai-Sum; Zhou, Li; Sun, Qi-Jun; Chan, Chi-Fai; Zhou, Ye; Han, Su-Ting; Yan, Yan; Wong, Wing-Tak; Wong, Ka-Leung; Roy, V A L

    2015-10-09

    Traditional utilization of photo-induced excitons is popularly but restricted in the fields of photovoltaic devices as well as photodetectors, and efforts on broadening its function have always been attempted. However, rare reports are available on organic field effect transistor (OFET) memory employing photo-induced charges. Here, we demonstrate an OFET memory containing a novel organic lanthanide complex Eu(tta)3ppta (Eu(tta)3 = Europium(III) thenoyltrifluoroacetonate, ppta = 2-phenyl-4,6-bis(pyrazol-1-yl)-1,3,5-triazine), in which the photo-induced charges can be successfully trapped and detrapped. The luminescent complex emits intense red emission upon ultraviolet (UV) light excitation and serves as a trapping element of holes injected from the pentacene semiconductor layer. Memory window can be significantly enlarged by light-assisted programming and erasing procedures, during which the photo-induced excitons in the semiconductor layer are separated by voltage bias. The enhancement of memory window is attributed to the increasing number of photo-induced excitons by the UV light. The charges are stored in this luminescent complex for at least 10(4) s after withdrawing voltage bias. The present study on photo-assisted novel memory may motivate the research on a new type of light tunable charge trapping photo-reactive memory devices.

  20. Determination for Enterobacter cloacae based on a europium ternary complex labeled DNA probe

    NASA Astrophysics Data System (ADS)

    He, Hui; Niu, Cheng-Gang; Zeng, Guang-Ming; Ruan, Min; Qin, Pin-Zhu; Liu, Jing

    2011-11-01

    The fast detection and accurate diagnosis of the prevalent pathogenic bacteria is very important for the treatment of disease. Nowadays, fluorescence techniques are important tools for diagnosis. A two-probe tandem DNA hybridization assay was designed for the detection of Enterobacter cloacae based on time-resolved fluorescence. In this work, the authors synthesized a novel europium ternary complex Eu(TTA) 3(5-NH 2-phen) with intense luminescence, high fluorescence quantum yield and long lifetime before. We developed a method based on this europium complex for the specific detection of original extracted DNA from E. cloacae. In the hybridization assay format, the reporter probe was labeled with Eu(TTA) 3(5-NH 2-phen) on the 5'-terminus, and the capture probe capture probe was covalent immobilized on the surface of the glutaraldehyde treated glass slides. The original extracted DNA of samples was directly used without any DNA purification and amplification. The detection was conducted by monitoring the fluorescence intensity from the glass surface after DNA hybridization. The detection limit of the DNA was 5 × 10 -10 mol L -1. The results of the present work proved that this new approach was easy to operate with high sensitivity and specificity. It could be conducted as a powerful tool for the detection of pathogen microorganisms in the environment.

  1. Surfactant-assisted emulsification dispersive liquid-liquid microextraction using 2-thenoyltrifluoroacetone as a chelating agent coupled with electrothermal atomic absorption spectrometry for the speciation of chromium in water and rice samples.

    PubMed

    Dokpikul, Nattawut; Chaiyasith, Wipharat Chuachuad; Sananmuang, Ratana; Ampiah-Bonney, Richmond J

    2018-04-25

    A novel method was developed by SAE-DLLME for chromium speciation in water and rice samples using 2-thenoyltrifluoroacetone (TTA) as a chelating reagent by ETAAS. The speciation of Cr(III) and Cr(VI) was achieved by complexation of Cr(III)-TTA and the total Cr was measured after reduction of Cr(VI) to Cr. The calibration graph was linear in the range of 0.02-2.50 µg L -1 , with a detection limit of 0.0052 µg L -1 . The %RSD was in range of 2.90-3.30% at 0.5, 1.5 and 2.5 µg L -1 of Cr(III), n = 5 and the EF was 54.47. The method was applied to chromium speciation and total chromium determination in real samples and gave recoveries in the range of 96.2-103.5% and 97.1-102.7% for Cr(III) and Cr(VI) in water samples and 93.7-103.5% of total Cr in rice samples. The accuracy of the method was evaluated by analysis of SRM 1573a with good agreement compared to the certified value. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. SABRE: a bio-inspired fault-tolerant electronic architecture.

    PubMed

    Bremner, P; Liu, Y; Samie, M; Dragffy, G; Pipe, A G; Tempesti, G; Timmis, J; Tyrrell, A M

    2013-03-01

    As electronic devices become increasingly complex, ensuring their reliable, fault-free operation is becoming correspondingly more challenging. It can be observed that, in spite of their complexity, biological systems are highly reliable and fault tolerant. Hence, we are motivated to take inspiration for biological systems in the design of electronic ones. In SABRE (self-healing cellular architectures for biologically inspired highly reliable electronic systems), we have designed a bio-inspired fault-tolerant hierarchical architecture for this purpose. As in biology, the foundation for the whole system is cellular in nature, with each cell able to detect faults in its operation and trigger intra-cellular or extra-cellular repair as required. At the next level in the hierarchy, arrays of cells are configured and controlled as function units in a transport triggered architecture (TTA), which is able to perform partial-dynamic reconfiguration to rectify problems that cannot be solved at the cellular level. Each TTA is, in turn, part of a larger multi-processor system which employs coarser grain reconfiguration to tolerate faults that cause a processor to fail. In this paper, we describe the details of operation of each layer of the SABRE hierarchy, and how these layers interact to provide a high systemic level of fault tolerance.

  3. New transparent flexible nanopaper as ultraviolet filter based on red emissive Eu(III) nanofibrillated cellulose

    NASA Astrophysics Data System (ADS)

    Zhang, Zhao; Chang, Hui; Xue, Bailiang; Han, Qing; Lü, Xingqiang; Zhang, Sufeng; Li, Xinping; Zhu, Xunjin; Wong, Wai-kwok; Li, Kecheng

    2017-11-01

    A new kind of highly red emissive and transparent nanopapers as ultraviolet filter are produced from lanthanide complex Eu(TTA)3(H2O)2 grafted nanofibrillated cellulose (NFC) by a filtration process using a Buchner funnel. The nanopapers Eu-NFC 1-4 with different thickness (0.023 mm, 1; 0.04 mm, 2; 0.081 mm, 3 and 0.1 mm, 4) possess a fibres with dimensions of approximately 50 nm in diameter and several micrometres in length. Those nanopapers exhibit excellent ultraviolet A (UVA; 320-400 nm) filter property and high optical transmittance (>73% at wavelength of 600 nm). The presence of Eu(TTA)3(H2O)2 in Eu-NFC nanopapers can block 97% UVA (at 348 nm) light and convert it into pure red emission (CIE: x = 0.663, y = 0.333) through the efficient triplet-triplet energy transfer process. The efficient red emission can significantly improve the photo-stability of β-diketones type UVA filter. It can sustain for 10 h without decomposition under UV irradiation at 365 nm, which makes it possible to be applied in UVA filters. Moreover, its low coefficient of thermal expansion (CTE: 6.39 ppm K-1 of nanocellulose), is superior to petroleum-based materials for red organic light-emitting devices.

  4. Photo-reactive charge trapping memory based on lanthanide complex

    NASA Astrophysics Data System (ADS)

    Zhuang, Jiaqing; Lo, Wai-Sum; Zhou, Li; Sun, Qi-Jun; Chan, Chi-Fai; Zhou, Ye; Han, Su-Ting; Yan, Yan; Wong, Wing-Tak; Wong, Ka-Leung; Roy, V. A. L.

    2015-10-01

    Traditional utilization of photo-induced excitons is popularly but restricted in the fields of photovoltaic devices as well as photodetectors, and efforts on broadening its function have always been attempted. However, rare reports are available on organic field effect transistor (OFET) memory employing photo-induced charges. Here, we demonstrate an OFET memory containing a novel organic lanthanide complex Eu(tta)3ppta (Eu(tta)3 = Europium(III) thenoyltrifluoroacetonate, ppta = 2-phenyl-4,6-bis(pyrazol-1-yl)-1,3,5-triazine), in which the photo-induced charges can be successfully trapped and detrapped. The luminescent complex emits intense red emission upon ultraviolet (UV) light excitation and serves as a trapping element of holes injected from the pentacene semiconductor layer. Memory window can be significantly enlarged by light-assisted programming and erasing procedures, during which the photo-induced excitons in the semiconductor layer are separated by voltage bias. The enhancement of memory window is attributed to the increasing number of photo-induced excitons by the UV light. The charges are stored in this luminescent complex for at least 104 s after withdrawing voltage bias. The present study on photo-assisted novel memory may motivate the research on a new type of light tunable charge trapping photo-reactive memory devices.

  5. On-Board GPS Clock Monitoring for Signal Integrity

    DTIC Science & Technology

    2010-11-01

    to-alert requirements to permit primary reliance for safety -of-life applications. Augmentation systems are being developed and deployed to address...virtually no false alerts from the combined system . With three running, on-board AFSs , occasional breaks of the error threshold can be allowed if the... system can be assured of transfer to another AFS within a period shorter than the required TTA. With only two AFSs on board running and measured

  6. A Program for Developing Automated Scientific-Information Processing in Maritime Economy,

    DTIC Science & Technology

    1983-11-17

    leat triple. The- exchange of tapes is n bviusocorrase. or. 0* 0 for the fishing brancft within the framework of a ftfw.Pltat ffkflng Agaemt(materials...from ZSR DnOOR Of Sooialist bep *46es3 a" MIS. T"e sept l oeeItu’e usmm we4 tta tft rpaxisatica of the first sta In the SUS40t or s4100irse.. ’teo~oal

  7. Identification and Characterization of Ovarian Carcinoma Peptide Epitopes Recognized by Cylotoxic T Lymphocytes

    DTIC Science & Technology

    2008-11-01

    CTC CCA CAG TGC CCC AGG TTA GAA CGG TCA GCA GAA TAG-2a 62 528 AGC GGC GGG CTG AAG GA GAG GGT AGG GTG GTC ATT GTG TCA TAG-2b 62 401 AGC GGC GGG CTG AAG...64:388–393 66. Zhang L, Conejo-Garcia JR, Katsaros D, Gimotty PA, Massobrio M, Regnani G, Makrigiannakis A, Gray H, Schlienger K, Liebman MN, Rubin SC

  8. Tibial and Femoral Tunnel Changes After ACL Reconstruction: A Prospective 2-Year Longitudinal MRI Study.

    PubMed

    Weber, Alexander E; Delos, Demetris; Oltean, Hanna N; Vadasdi, Katherine; Cavanaugh, John; Potter, Hollis G; Rodeo, Scott A

    2015-05-01

    Tunnel widening after anterior cruciate ligament reconstruction (ACL-R) is a well-accepted and frequent phenomenon, yet little is known regarding its origin or natural history. To prospectively evaluate the cross-sectional area (CSA) changes in tibial and femoral bone tunnels after ACL-R with serial MRI. Case series; Level of evidence, 4. Patients underwent arthroscopic ACL-R with the same surgeon, surgical technique, and rehabilitation protocol. Each patient underwent preoperative dual-energy x-ray absorptiometry and clinical evaluation, as well as postoperative time zero MRI followed by subsequent MRI and clinical examination, including functional and subjective outcome tests, at 6, 12, 24, 52, and 104 weeks. Tibial and femoral tunnel CSA was measured on each MRI at tunnel aperture (ttA and ftA), midsection (ttM and ftM), and exit (ttE and ftE). Logistic regression modeling was used to examine the predictive value of demographic data and preoperative bone quality (as measured by dual-energy x-ray absorptiometry) on functional outcome scores, manual and instrumented laxity measurements, and changes in tunnel area over time. Eighteen patients (including 12 men), mean age 35.5±8.7 years, underwent ACL-R. There was significant tunnel expansion at ttA and ftA sites 6 weeks postoperatively (P=.024 and .0045, respectively). Expansion continued for 24 weeks, with progressive tunnel narrowing thereafter. Average ttA CSA was significantly larger than ftA CSA at all times. The ttM significantly expanded after 6 weeks (P=.06); continued expansion to week 12 was followed by 21 months of reduction in tunnel diameter. The ftM and both ttE and ftE sites decreased in CSA over the 2 years. Median Lysholm and International Knee Documentation Committee scores significantly improved at final follow-up (P=.0083 and <.0001, respectively), and patients returned to preoperative activity levels. Pivot shift significantly decreased (P<.0001). Younger age (<30 years), male sex, and delayed ACL-R (>1 year from time of injury) predicted increased tunnel widening and accelerated expansion in CSA (P<.005). Tunnel expansion after ACL-R occurs early and primarily at the tunnel apertures. Expansion may not affect clinical outcome. Younger age, male sex, and delay from injury to ACL-R may be potential risks for enlargement. © 2015 The Author(s).

  9. Differences in Military Obstacle Course Performance Between Three Energy-Storing and Shock-Adapting Prosthetic Feet in High-Functioning Transtibial Amputees: A Double-Blind, Randomized Control Trial.

    PubMed

    Highsmith, M Jason; Kahle, Jason T; Miro, Rebecca M; Lura, Derek J; Carey, Stephanie L; Wernke, Matthew M; Kim, Seok Hun; Quillen, William S

    2016-11-01

    Approximately 683 persons engaged in military service experienced transtibial amputation (TTA) related to recent war in Iraq and Afghanistan. Military TTAs function at a level beyond basic ambulation. No empirical data demonstrate which higher functioning prosthetic feet maximize injured service personnel's ability to continue performing at a level commensurate with return to duty. This study's purpose was to determine which of three high-functioning, energy-storing prosthetic feet maximize performance and preference in a field obstacle course (OC) and to quantify physical performance differences between TTAs and high-functioning nonamputees. A randomized, double-blind, repeated measures experimental design compared three prosthetic feet (Ossur Variflex, Endolite Elite Blade, and Ossur Re-Flex Rotate) during performance on a field OC. TTAs accommodated with study feet and the OC before assessment. 14 TTAs and 14 nonamputee controls completed the course. Subjective and objective performance differences were compared across feet conditions and between groups. Total OC completion times were similar between prosthetic feet: Elite-Blade (419 seconds ± 130), Variflex (425 seconds ± 144), and Re-Flex Rotate (444 seconds ± 220). Controls' OC completion time (287.2 seconds ± 58) was less (p ≤ 0.05) than TTA times. In total, controls had faster completion times (p ≤ 0.05) compared to all prosthetic feet conditions in 13/17 obstacles. Re-Flex Rotate had 2 additional obstacles different (p ≤ 0.05) than controls and required more time to complete. Median RPE values were lower (p ≤ 0.05) for controls than TTA regardless of foot. Regarding foot preference for OC completion, 7/14 (50%) preferred Elite Blade, 5/14 (36%) preferred Re-Flex Rotate, and the remaining 2/14 (14%) preferred Variflex. Controls completed the OC faster and with less effort than TTAs regardless of prosthetic foot. No clear differences in prosthetic feet emerged during OC completion; however, individual task performance, perceived effort, and preference resulted in trends of slight performance improvement with and preference for Elite Blade, a dual function energy-storing and return foot combined with vertical shock absorption. Understanding how to maximally improve performance in such functional tasks may allow service members to best sustain physical fitness, return to their military occupational specialty and possibly in-theater duty. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

  10. Real-time patient-specific finite element analysis of internal stresses in the soft tissues of a residual limb: a new tool for prosthetic fitting.

    PubMed

    Portnoy, S; Yarnitzky, G; Yizhar, Z; Kristal, A; Oppenheim, U; Siev-Ner, I; Gefen, A

    2007-01-01

    Fitting of a prosthetic socket is a critical stage in the process of rehabilitation of a trans-tibial amputation (TTA) patient, since a misfit may cause pressure ulcers or a deep tissue injury (DTI: necrosis of the muscle flap under intact skin) in the residual limb. To date, prosthetic fitting typically depends on the subjective skills of the prosthetist, and is not supported by biomedical instrumentation that allows evaluation of the quality of fitting. Specifically, no technology is presently available to provide real-time continuous information on the internal distribution of mechanical stresses in the residual limb during fitting of the prosthesis, or while using it and this severely limits patient evaluations. In this study, a simplified yet clinically oriented patient-specific finite element (FE) model of the residual limb was developed for real-time stress analysis. For this purpose we employed a custom-made FE code that continuously calculates internal stresses in the residual limb, based on boundary conditions acquired in real-time from force sensors, located at the limb-prosthesis interface. Validation of the modeling system was accomplished by means of a synthetic phantom of the residual limb, which allowed simultaneous measurements of interface pressures and internal stresses. Human studies were conducted subsequently in five TTA patients. The dimensions of bones and soft tissues were obtained from X-rays of the residual limb of each patient. An indentation test was performed in order to obtain the effective elastic modulus of the soft tissues of the residual limb. Seven force sensors were placed between the residual limb and the prosthetic liner, and subjects walked on a treadmill during analysis. Generally, stresses under the shinbones were approximately threefold higher than stresses at the soft tissues behind the bones. Usage of a thigh corset decreased the stresses in the residual limb during gait by approximately 80%. Also, the stresses calculated during the trial of a subject who complained about pain and discomfort were the highest, confirming that his socket was not adequately fitted. We conclude that real-time patient-specific FE analysis of internal stresses in deep soft tissues of the residual limb in TTA patients is feasible. This method is promising for improving the fitting of prostheses in the clinical setting and for protecting the residual limb from pressure ulcers and DTI.

  11. Interdisciplinary Studies on the Combat Readiness and Health Issues Faced by Military Personnel

    DTIC Science & Technology

    2009-09-01

    related activity in single subjects, and this facilitates clinical diagnosis in which single subjects are the focus of investigation. Methods...Good Clinical Practice Guidelines, the Declaration of Helsinki, and the U.S. Code of Federal Regulations. Written and informed consent was obtained from...S, and a temporal loading T. For two triplets: (Fa, Sa, Ta) and (Fb, Sb, Tb), we define the triplet similarity metric Cab = FTa Fb STaSb TTa

  12. Generation of Space Debris from Explosion of Spacecrafts’ Fuel Tanks

    DTIC Science & Technology

    1994-01-01

    parui a (2.21):11i",tta pit of jiibl 21 ; n&’(-23)A ineectionl ’On-.,Ar bola (2.191),point 411-ouepnstoti on D id (b~ior time eain le co~didi~-higli...4.4). (4,5) (1111 be vasily solved itow. At first we find: A10 (4.9) and then according m (1.-4) all VjY van bi- (1vt(’rmlne(. 4 Notice that if we

  13. Pacific Operational Science and Technology Conference

    DTIC Science & Technology

    2008-07-17

    AOR • Think long term-ten to fifty years • Technology assessment • Systems thinking and interaction • Capitalize on technology futures – Renewable ... Renewable energy • Improved mobility • Transportation security • National competitiveness 24 Managed by UT-Battelle for the Department of Energy...Started Cost Schedule Technical TTA CB-034 Tools and Protocols for Agro Screening Ag Screening Tools 500 4,138 3,500 2,500 2,525 3,163 N CB-011 CB-042 Ag

  14. Theta EEG source localization using LORETA in partial epilepsy patients with and without medication.

    PubMed

    Clemens, B; Bessenyei, M; Fekete, I; Puskás, S; Kondákor, I; Tóth, M; Hollódy, K

    2010-06-01

    To investigate and localize the sources of spontaneous, scalp-recorded theta activity in patients with partial epilepsy (PE). Nine patients with beginning, untreated PE (Group 1), 31 patients with already treated PE (Group 2), and 14 healthy persons were investigated by means of spectral analysis and LORETA, low resolution electromagnetic tomography (1 Hz very narrow band analysis, age-adjusted, Z-scored values). The frequency of main interest was 4-8 Hz. Group analysis: Group 1 displayed bilateral theta maxima in the temporal theta area (TTA), parietal theta area (PTA), and frontal theta area (FTA). In Group 2, theta activity increased all over the scalp as compared to the normative mean (Z=0) and also to Group 1. Maximum activity was found in the TTA, PTA, and FTA. However, in the PTA and FTA the centers of the abnormality shifted towards the medial cortex. Individual analysis: all the patients showed preferential activation (maximum Z-values) within one of the three theta areas. EEG activity in the theta band is increased in anatomically meaningful patterns in PE patients, which differs from the anatomical distribution of theta in healthy persons. The findings contribute to our understanding of the sources of theta rhythms and the pathophysiology of PE. Copyright 2010 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  15. A mixture model for bovine abortion and foetal survival.

    PubMed

    Hanson, Timothy; Bedrick, Edward J; Johnson, Wesley O; Thurmond, Mark C

    2003-05-30

    The effect of spontaneous abortion on the dairy industry is substantial, costing the industry on the order of US dollars 200 million per year in California alone. We analyse data from a cohort study of nine dairy herds in Central California. A key feature of the analysis is the observation that only a relatively small proportion of cows will abort (around 10;15 per cent), so that it is inappropriate to analyse the time-to-abortion (TTA) data as if it were standard censored survival data, with cows that fail to abort by the end of the study treated as censored observations. We thus broaden the scope to consider the analysis of foetal lifetime distribution (FLD) data for the cows, with the dual goals of characterizing the effects of various risk factors on (i). the likelihood of abortion and, conditional on abortion status, on (ii). the risk of early versus late abortion. A single model is developed to accomplish both goals with two sets of specific herd effects modelled as random effects. Because multimodal foetal hazard functions are expected for the TTA data, both a parametric mixture model and a non-parametric model are developed. Furthermore, the two sets of analyses are linked because of anticipated dependence between the random herd effects. All modelling and inferences are accomplished using modern Bayesian methods. Copyright 2003 John Wiley & Sons, Ltd.

  16. Dual functionality of triticale as a novel dietary source of prebiotics with antioxidant activity in fermented dairy products.

    PubMed

    Agil, Rania; Hosseinian, Farah

    2012-03-01

    The objectives of this study were to: (i) define the optimum concentration of triticale bran (TB) that can be incorporated in yogurt, (ii) evaluate the prebiotic effects of TB on microbial viability, pH and total titratable acidity (TTA) in yogurt across 28 days of cold storage, and (iii) measure the oxygen radical absorbance capacity (ORAC) of water-extractable polysaccharides (WEP) in TB. Lactobacillus bulgaricus and Streptococcus thermophilus were used as starter cultures. Lactobacillus acidophilus and Bifidobacterium lactis were used as probiotics. A concentration of 4% TB in yogurt was determined to be the maximum amount that could be added without causing synersis. By day 7, the number of bacteria greatly increased in yogurt samples containing TB and maintained higher viable bacteria counts at the end of the cold storage period, in comparison to controls (P ≤ 0.05). Confirming this data was the lower pH levels and higher TTA values of TB yogurt samples exhibited throughout 28 days (P ≤ 0.05). Polysaccharide extracts of TB exhibited strong antioxidant activity with an ORAC value of 33.86 ± 2.30 μmol trolox equivalents (TE)/g of bran. Results of this study suggest that TB may serve as a new prebiotic and antioxidant source for functional foods and nutraceutical applications.

  17. Lack of Humoral Immune Response to the Tetracycline (Tet) Activator in Rats Injected Intracranially with Tet-off rAAV Vectors

    PubMed Central

    Han, Ye; Chang, Qin A.; Virag, Tamas; West, Neva C.; George, David; Castro, Maria G.; Bohn, Martha C.

    2010-01-01

    The ability to safely control transgene expression from viral vectors is a long-term goal in the gene therapy field. We have previously reported tight regulation of GFP expression in rat brain using a self-regulating tet-off rAAV vector. The immune responses against tet regulatory elements observed by other groups in nonhuman primates after intramuscular injection of tet-on encoding vectors raise concerns about the clinical value of tet-regulated vectors. However, previous studies have not examined immune responses following injection of AAV vectors into brain. Therefore, rat striatum was injected with tet-off rAAV harboring a therapeutic gene for Parkinson's disease, either hAADC or hGDNF. The expression of each gene was tightly controlled by the tet-off regulatory system. Using an ELISA developed with purified GST-tTA protein, no detectable immunogenicity against tTA was observed in sera of rats that received an intrastriatal injection of either vector. In contrast, sera from rats intradermally injected with an adenovirus containing either tTA or rtTA, as positive controls, had readily detectable antibodies. These observations suggest that tet-off rAAV vectors do not elicit an immune response when injected into rat brain and that these may offer safer vectors for Parkinson's disease than vectors with constitutive expression. PMID:20164859

  18. Exploring the Dynamics of Propeller Loops in Human Telomeric DNA Quadruplexes Using Atomistic Simulations.

    PubMed

    Islam, Barira; Stadlbauer, Petr; Gil-Ley, Alejandro; Pérez-Hernández, Guillermo; Haider, Shozeb; Neidle, Stephen; Bussi, Giovanni; Banas, Pavel; Otyepka, Michal; Sponer, Jiri

    2017-06-13

    We have carried out a series of extended unbiased molecular dynamics (MD) simulations (up to 10 μs long, ∼162 μs in total) complemented by replica-exchange with the collective variable tempering (RECT) approach for several human telomeric DNA G-quadruplex (GQ) topologies with TTA propeller loops. We used different AMBER DNA force-field variants and also processed simulations by Markov State Model (MSM) analysis. The slow conformational transitions in the propeller loops took place on a scale of a few μs, emphasizing the need for long simulations in studies of GQ dynamics. The propeller loops sampled similar ensembles for all GQ topologies and for all force-field dihedral-potential variants. The outcomes of standard and RECT simulations were consistent and captured similar spectrum of loop conformations. However, the most common crystallographic loop conformation was very unstable with all force-field versions. Although the loss of canonical γ-trans state of the first propeller loop nucleotide could be related to the indispensable bsc0 α/γ dihedral potential, even supporting this particular dihedral by a bias was insufficient to populate the experimentally dominant loop conformation. In conclusion, while our simulations were capable of providing a reasonable albeit not converged sampling of the TTA propeller loop conformational space, the force-field description still remained far from satisfactory.

  19. Exploring the Dynamics of Propeller Loops in Human Telomeric DNA Quadruplexes Using Atomistic Simulations

    PubMed Central

    2017-01-01

    We have carried out a series of extended unbiased molecular dynamics (MD) simulations (up to 10 μs long, ∼162 μs in total) complemented by replica-exchange with the collective variable tempering (RECT) approach for several human telomeric DNA G-quadruplex (GQ) topologies with TTA propeller loops. We used different AMBER DNA force-field variants and also processed simulations by Markov State Model (MSM) analysis. The slow conformational transitions in the propeller loops took place on a scale of a few μs, emphasizing the need for long simulations in studies of GQ dynamics. The propeller loops sampled similar ensembles for all GQ topologies and for all force-field dihedral-potential variants. The outcomes of standard and RECT simulations were consistent and captured similar spectrum of loop conformations. However, the most common crystallographic loop conformation was very unstable with all force-field versions. Although the loss of canonical γ-trans state of the first propeller loop nucleotide could be related to the indispensable bsc0 α/γ dihedral potential, even supporting this particular dihedral by a bias was insufficient to populate the experimentally dominant loop conformation. In conclusion, while our simulations were capable of providing a reasonable albeit not converged sampling of the TTA propeller loop conformational space, the force-field description still remained far from satisfactory. PMID:28475322

  20. Remote Synchronization Experiments for Future Quasi-Zenith Satellite System Using Current Geostationary Satellites

    DTIC Science & Technology

    2008-12-01

    Timekeeping,” Application Note 1289 (Hewlett-Packard), p. 60. [5] F. Tappero, A. Dempster, T . Iwata, M. Imae, T . Ikegami , Y. Fukuyama, K. Hagimoto, and A...the timing controller are also received. Modem ( T ): The Modem ( T ) is one of the three TWSTFT modems used in the experiments (“ T ” stands for...PN signal. In the experiments, the modem ( T ) was referenced to the time signal of the TTA and the RESSOX control signal was transmitted to the modem

  1. Biomass and nutrient concentration of sweet corn roots and shoots under organic amendments application.

    PubMed

    Ahmad, Amjad A; Fares, Ali; Paramasivam, Sivapatham; Elrashidi, Moustafa A; Savabi, Reza M

    2009-09-01

    Two field experiments were conducted at the Waimanalo research station on the island of O'ahu, Hawaii to study the effect of chicken (CM) and dairy (DM) manures on biomass and nutrient concentration in sweet corn roots and shoots. Sweet corn (super sweet 10, Zea Mays L. subsp. mays) was grown for two consecutive growing seasons under four rates of application (0, 168, 337, and 672 kg ha(-1) total N equivalent) and one time (OTA) or two time (TTA) applications of organic manure types and rates. There were significant effects of types, rates, and number of manure applications on dry biomass and macro- and micro-nutrient concentration in roots and shoots tissues. Results of root tissue indicated a significant accumulation of N and C under CM and DM treatments compared with the control treatment. Manure application rates significantly increased the accumulation of N and C in root tissue. Dry weight of roots and shoots and both macro- and micro-nutrient contents in the plant tissues significantly increased under TTA treatment compared with OTA treatment. There was a significant correlation (r(2) = 0.46 to 0.81) between root biomass, macro-, and micro-nutrient contents during both growing seasons. The results of the study indicates that amending soils with CM at the highest application rate provided the best crop performance in terms of root and shoot biomass, crop N, C, and other macro- and micro-nutrients.

  2. Performance Improvement Through Indexing of Turbine Airfoils. Part 2; Numerical Simulation

    NASA Technical Reports Server (NTRS)

    Griffin, Lisa W.; Huber, Frank W.; Sharma, Om P.

    1996-01-01

    An experimental/analytical study has been conducted to determine the performance improvements achievable by circumferentially indexing succeeding rows of turbine stator airfoils. A series of tests was conducted to experimentally investigate stator wake clocking effects on the performance of the space shuttle main engine (SSME) alternate turbopump development (ATD) fuel turbine test article (TTA). The results from this study indicate that significant increases in stage efficiency can be attained through application of this airfoil clocking concept. Details of the experiment and its results are documented in part 1 of this paper. In order to gain insight into the mechanisms of the performance improvement, extensive computational fluid dynamics (CFD) simulations were executed. The subject of the present paper is the initial results from the CFD investigation of the configurations and conditions detailed in part 1 of the paper. To characterize the aerodynamic environments in the experimental test series, two-dimensional (2D), time accurate, multistage, viscous analyses were performed at the TTA midspan. Computational analyses for five different circumferential positions of the first stage stator have been completed. Details of the computational procedure and the results are presented. The analytical results verify the experimentally demonstrated performance improvement and are compared with data whenever possible. Predictions of time-averaged turbine efficiencies as well as gas conditions throughout the flow field are presented. An initial understanding of the turbine performance improvement mechanism based on the results from this investigation is described.

  3. ECONOMIC EVALUATIONS OF INTERVENTIONS FOR TRANSTIBIAL AMPUTEES: A SCOPING REVIEW OF COMPARATIVE STUDIES.

    PubMed

    Highsmith, M Jason; Kahle, Jason T; Lewandowski, Amanda; Klenow, Tyler D; Orriola, John J; Miro, Rebecca M; Hill, Owen T; Raschke, Sylvia Ursula; Orendurff, Michael S; Highsmith, James T; Sutton, Bryce S

    2016-09-01

    Transtibial amputation (TTA) is life-altering emotionally, functionally, and economically. The economic impact to all stakeholders is largely unknown, as is the cost-effectiveness of prosthetic intervention. This scoping report's purpose was to determine if there is sufficient evidence to conduct a formal systematic review or meta-analysis in any particular prosthetic intervention area and to determine if any evidence statements could be synthesized relative to economic evaluation of interventions provided to patients with TTA. The scoping review revealed six articles representing three topical areas of transtibial care: Care Models, Prosthetic Treatment, and Prosthetic Sockets. All six articles were cost-identification or cost-consequence design and included a total of 704 subjects. Presently, it can be concluded with moderate confidence that specific weight-bearing and total-contact sockets for transtibial amputees are functionally and economically equivalent in the short term when costs, delivery time, and all stakeholder perspectives are considered. Long-term socket outcomes are relatively unexplored. Further primary research is needed beyond this to determine cost-effectiveness for other areas of transtibial prosthetic care although clinical outcomes are somewhat established through systematic review and meta-analysis in other areas of care. Conversely, evaluation of narrative economic reports relative to transtibial care may be sufficient to warrant further analysis. Guidance from the profession may also be useful in devising a strategy for how to assure economic analyses are a routine element of future prosthetic science.

  4. Murine Stem Cell-Based Retrovirus Production for Marking Primary Mouse Mammary Cells for Metastasis Studies.

    PubMed

    Beverly, Levi J; Podsypanina, Katrina

    2016-02-01

    Since the introduction of retroviral vector technology, permanent genetic marking of cells has considerably contributed to the understanding of different physiological and disease processes in vivo. Recent marking strategies aim to elucidate the contribution of cells on the clonal level, and the advent of fluorescent proteins has opened new avenues for the in vivo analysis of gene-marked cells. Gene-modified cells are easily identifiable (e.g., via the introduced fluorescent protein) within whole organ structures, allowing one to measure the contribution of transduced cells to malignant outgrowth. In our laboratory, we use the tetracycline-inducible system to study oncogene cooperation in metastatic progression. We use bicistronic retroviruses expressing the tetracycline transactivator (tTA) and the candidate gene (MIT-gene) or the tTA alone (MIT-Rx) to infect primary mammary cells from mice harboring tetracycline-inducible transgenes. This allows for constitutive expression of the candidate gene and tTA-dependent expression of the inducible oncogene. We also use MIG-based vectors, which allow for constitutive expression of the candidate gene and a green fluorescent protein. Here we describe how to produce retroviral particles carrying both MIT- and MIG-based vectors. Because of the fragility of the retroviral envelope, we do not attempt to concentrate the virus, and we directly use packaging cell media to infect primary epithelial cells (either normal or tumor). Infected cells can be transplanted into recipient mice to investigate metastatic colonization. © 2016 Cold Spring Harbor Laboratory Press.

  5. Synthesis of oxide and spinel nanocrystals for use in solid state lighting

    NASA Astrophysics Data System (ADS)

    Foley, Megan Elizabeth

    In this dissertation, microwave chemistry is employed to synthesize a variety of different crystalline nanoparticles (NPs). This introduction will describe the structures, properties and applications of the NPs studied within the dissertation, with a main focus being on ligand sensitization for the goal of enhanced luminescence. The use of metal acetylacetonate complexes to make Europium (III) doped Ytrrium (Y2O3) NPs is explored, where the acetylacetonate acts both as a source of oxygen for the synthesis of Y2O3, as well as an organic chromophore acting as an "antenna" for the absorption of light and subsequent excitation transfer to the incorporated Europium (III) (Chapter 2). Other host materials are investigated by method of metal acetylacetonate decomposition to synthesize a variety of different nanospinels, having the general formula AB2X4, with sulfide variants made by decomposition of diethyldithiocarbamate, (Chapter 3). The antenna ligand thenoyltrifluoroacetone (tta), which is known to undergo a Dexter energy transfer (DET) mechanism to efficiently sensitize Europium (III) emission, is used to determine the distance of energy transfer in Europium (III) doped nanospinels by passivating the surface of the nanospinel with a tta (Chapter 4). A variety of ligands are explored in order to optimize the sensitization efficiency in relation to the difference in energy between the singlet and triplet levels of the ligands versus the 5D0 and 5D4 energy levels of Europium (III) and Terbium (III) respectively (Chapter 5).

  6. Lanthanide-based laser-induced phosphorescence for spray diagnostics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Voort, D. D. van der, E-mail: d.d.v.d.voort@tue.nl; Water, W. van de; Kunnen, R. P. J.

    2016-03-15

    Laser-induced phosphorescence (LIP) is a relatively recent and versatile development for studying flow dynamics. This work investigates certain lanthanide-based molecular complexes for their use in LIP for high-speed sprays. Lanthanide complexes in solutions have been shown to possess long phosphorescence lifetimes (∼1-2 ms) and to emit light in the visible wavelength range. In particular, europium and terbium complexes are investigated using fluorescence/phosphorescence spectrometry, showing that europium-thenoyltrifluoracetone-trioctylphosphineoxide (Eu-TTA-TOPO) can be easily and efficiently excited using a standard frequency-tripled Nd:YAG laser. The emitted spectrum, with maximum intensity at a wavelength of 614 nm, is shown not to vary strongly with temperature (293-383more » K). The decay constant of the phosphorescence, while independent of ambient pressure, decreases by approximately 12 μs/K between 323 and 373 K, with the base level of the decay constant dependent on the used solvent. The complex does not luminesce in the gas or solid state, meaning only the liquid phase is visualized, even in an evaporating spray. By using an internally excited spray containing the phosphorescent complex, the effect of vaporization is shown through the decrease in measured intensity over the length of the spray, together with droplet size measurements using interferometric particle imaging. This study shows that LIP, using the Eu-TTA-TOPO complex, can be used with different solvents, including diesel surrogates. Furthermore, it can be easily handled and used in sprays to investigate spray breakup and evaporation.« less

  7. 3D tumor tissue analogs and their orthotopic implants for understanding tumor-targeting of microenvironment-responsive nanosized chemotherapy and radiation.

    PubMed

    Sethi, Pallavi; Jyoti, Amar; Swindell, Elden P; Chan, Ryan; Langner, Ulrich W; Feddock, Jonathan M; Nagarajan, Radhakrishnan; O'Halloran, Thomas V; Upreti, Meenakshi

    2015-11-01

    An appropriate representation of the tumor microenvironment in tumor models can have a pronounced impact on directing combinatorial treatment strategies and cancer nanotherapeutics. The present study develops a novel 3D co-culture spheroid model (3D TNBC) incorporating tumor cells, endothelial cells and fibroblasts as color-coded murine tumor tissue analogs (TTA) to better represent the tumor milieu of triple negative breast cancer in vitro. Implantation of TTA orthotopically in nude mice, resulted in enhanced growth and aggressive metastasis to ectopic sites. Subsequently, the utility of the model is demonstrated for preferential targeting of irradiated tumor endothelial cells via radiation-induced stromal enrichment of galectin-1 using anginex conjugated nanoparticles (nanobins) carrying arsenic trioxide and cisplatin. Demonstration of a multimodal nanotherapeutic system and inclusion of the biological response to radiation using an in vitro/in vivo tumor model incorporating characteristics of tumor microenvironment presents an advance in preclinical evaluation of existing and novel cancer nanotherapies. Existing in-vivo tumor models are established by implanting tumor cells into nude mice. Here, the authors described their approach 3D spheres containing tumor cells, enodothelial cells and fibroblasts. This would mimic tumor micro-environment more realistically. This interesting 3D model should reflect more accurately tumor response to various drugs and would enable the design of new treatment modalities. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Near-Infrared-to-Visible Photon Upconversion Enabled by Conjugated Porphyrinic Sensitizers under Low-Power Noncoherent Illumination.

    PubMed

    Olivier, Jean-Hubert; Bai, Yusong; Uh, Hyounsoo; Yoo, Hyejin; Therien, Michael J; Castellano, Felix N

    2015-06-04

    We report four supermolecular chromophores based on (porphinato)zinc(II) (PZn) and (polypyridyl)metal units bridged via ethyne connectivity (Pyr1RuPZn2, Pyr1RuPZnRuPyr1, Pyr1RuPZn2RuPyr1, and OsPZn2Os) that fulfill critical sensitizer requirements for NIR-to-vis triplet-triplet annihilation upconversion (TTA-UC) photochemistry. These NIR sensitizers feature: (i) broad, high oscillator strength NIR absorptivity (700 nm < λ(max(NIR)) < 770 nm; 6 × 10(4) M(-1) cm(-1) < extinction coefficient (λ(max(NIR))) < 1.6 × 10(5) M(-1) cm(-1); 820 cm(-1) < fwhm < 1700 cm(-1)); (ii) substantial intersystem crossing quantum yields; (iii) long, microsecond time scale T1 state lifetimes; and (iv) triplet states that are energetically poised for exergonic energy transfer to the molecular annihilator (rubrene). Using low-power noncoherent illumination at power densities (1-10 mW cm(-2)) similar to that of terrestrial solar photon illumination conditions, we demonstrate that Pyr1RuPZn2, Pyr1RuPZn2RuPyr1, and Pyr1RuPZnRuPyr1 sensitizers can be used in combination with the rubrene acceptor/annihilator to achieve TTA-UC: these studies represent the first examples whereby a low-power noncoherent NIR light source drives NIR-to-visible upconverted fluorescence centered in a spectral window within the bandgap of amorphous silicon.

  9. New Synthetic and Assembly Methodology for Guiding Nanomaterial Assembly with High Fidelity into 1D Clusters and 3D Crystals Using Biomimetic Interactions

    DTIC Science & Technology

    2015-03-26

    sequences Type Sequence (* = Phosphorothioate bases) Tm S/S𔃻/S𔃼 (°C) U T*T*T* T*T*T TTT TTA CTC ACC TAT ATC A 16.5 U𔃻 GTG AGT A U...27 T𔃻 GTC GTG A T𔃼 CAA AGT GT T𔃽 CAA AGT GTG TCG TGA 27% 25% 48% F re qu en cy ( % ) 0 20 40 60 80 100 0-30° 31-60° 61-90° (b) (i) (ii

  10. The Prevalence and Importance of Epithelial Plasticity in Metastatic Prostate Cancer

    DTIC Science & Technology

    2014-10-01

    34TGFB2"(Supplementary"FigureŘA;" gray "bars)."Using"i.v.ൠ" 18" " serial"passages"one"and"two"as"a"model"for"an"METVindependent"metastatic"event"and"i.v...isoforms! in!CSR99s,!except! the! following! human!primers! to!detect!FGFR2!were!used:!5’RGCA AGG TTT ACA GTG ATG CCC AGC CR3’!and!5’RGGA TGA CTG TTA

  11. Preliminary Draft Environmental Impact Statement. Electronic Combat Test Capability, Utah Test and Training Range

    DTIC Science & Technology

    1989-07-01

    operations beginning in 1996 . Until that time, staging will be conducted from Hill AFB and Michael AAF. ES-26 HE wF-lr 7,rr)~f~)~ ~ D 0t- 0 0 4J 444(U 44’ -P...constructed over a period of years (1990- 1996 ). Where possible, the network will follow existing or proposed new roads to minimize ground disturbance...attendant roads, power lines, and fiber optics between 1991 and 1996 . 4. Construction of a gapfiller radar in 1992. 5. Construction of TTA range

  12. Ping-Pong Energy Transfer in a Boron Dipyrromethane Containing Pt(II)-Schiff Base Complex: Synthesis, Photophysical Studies, and Anti-Stokes Shift Increase in Triplet-Triplet Annihilation Upconversion.

    PubMed

    Razi, Syed S; Koo, Yun Hee; Kim, Woojae; Yang, Wenbo; Wang, Zhijia; Gobeze, Habtom; D'Souza, Francis; Zhao, Jianzhang; Kim, Dongho

    2018-05-07

    A boron dipyrromethane (BDP)-containing Pt(II)-Schiff base complex (Pt-BDP), showing ping-pong singlet-triplet energy transfer, was synthesized, and the detailed photophysical properties were investigated using various steady-state and time-resolved transient spectroscopies. Femtosecond/nanosecond transient absorption spectroscopies demonstrated that, upon selective excitation of the BDP unit in Pt-BDP at 490 nm, Förster resonance energy transfer from the BDP unit to the Pt(II) coordination center occurred (6.7 ps), accompanied by an ultrafast intersystem crossing at the Pt(II) coordination center (<1 ps) and triplet-triplet energy transfer back to the BDP moiety (148 ps). These processes generated a triplet state localized at BDP, and the lifetime was 103.2 μs, much longer than the triplet-state lifetime of Pt-Ph (3.5 μs), a complex without the BDP moiety. Finally, Pt-BDP was used as a triplet photosensitizer for triplet-triplet annihilation (TTA) upconversion through selective excitation of the BDP unit or the Pt(II) coordination center at lower excitation energy. An upconversion quantum yield of up to 10% was observed with selective excitation of the BDP moiety, and a large anti-Stokes shift of 0.65 eV was observed upon excitation of the lower-energy band of the Pt(II) coordination center. We propose that using triplet photosensitizers with the ping-pong energy-transfer process may become a useful method for increasing the anti-Stokes shift of TTA upconversion.

  13. Mesenchymal stem cells in osteotomy repair after tibial tuberosity advancement in dogs with cranial cruciate ligament injury.

    PubMed

    Rocha Dos Santos, Clarissa; da Rocha Filgueiras, Richard; Furtado Malard, Patrícia; Rodrigues da Cunha Barreto-Vianna, Andre; Nogueira, Kaique; da Silva Leite, Carolina; Maurício Mendes de Lima, Eduardo

    2018-06-14

    The cranial cruciate ligament rupture (CCLR) is the most commonly encountered orthopedic condition in dogs. Among the various techniques to treat this condition, tibial tuberosity advancement (TTA) has been used to obtain rapid recovery of the affected knee. The objective of this study was to evaluate the viability of the use of mesenchymal stem cells (MSC) implanted in the osteotomy site obtained by TTA in nine dogs diagnosed with CCLR. The MSC were isolated from the adipose tissue of the dogs and cultured for eight days, the animals were divided into two groups. Animals from the treated group (GT) received cell transport medium containing about 1.5 millions MSC, and the animals from the control group (GC) received only the cell transport medium. The study was performed in a double-blind manner using radiographs acquired on days 15, 30, 60 and 120 after the procedure. Evaluations of the density of the trabecular bone were performed using image analysis software. The results were subjected to descriptive statistical analysis, followed by the normality test, Chi-square test, Mann-Whitney test and Tukey's multiple comparison test for p ≤ 0.05. After 30 days of the procedure, the animals of the GT presented an ossification mean 36.45% greater (p ≤ 0.033) than the GC, and there were no statistical differences for the other periods. Despite the total bone ossification within the expected period, there was no minimization of the estimated recovery time with the application of MSC, and inflammatory factors should be considered for reassessment of the therapeutic intervention time.

  14. Identification of trunk and pelvis movement compensations in patients with transtibial amputation using angular momentum separation.

    PubMed

    Gaffney, Brecca M; Murray, Amanda M; Christiansen, Cory L; Davidson, Bradley S

    2016-03-01

    Patients with unilateral dysvascular transtibial amputation (TTA) have a higher risk of developing low back pain than their healthy counterparts, which may be related to movement compensations used in the absence of ankle function. Assessing components of segmental angular momentum provides a unique framework to identify and interpret these movement compensations alongside traditional observational analyses. Angular momentum separation indicates two components of total angular momentum: (1) transfer momentum and (2) rotational momentum. The objective of this investigation was to assess movement compensations in patients with dysvascular TTA, patients with diabetes mellitus (DM), and healthy controls (HC) by examining patterns of generating and arresting trunk and pelvis segmental angular momenta during gait. We hypothesized that all groups would demonstrate similar patterns of generating/arresting total momentum and transfer momentum in the trunk and pelvis in reference to the groups (patients with DM and HC). We also hypothesized that patients with amputation would demonstrate different (larger) patterns of generating/arresting rotational angular momentum in the trunk. Patients with amputation demonstrated differences in trunk and pelvis transfer angular momentum in the sagittal and transverse planes in comparison to the reference groups, which indicates postural compensations adopted during walking. However, patients with amputation demonstrated larger patterns of generating and arresting of trunk and pelvis rotational angular momentum in comparison to the reference groups. These segmental rotational angular momentum patterns correspond with high eccentric muscle demands needed to arrest the angular momentum, and may lead to consequential long-term effects such as low back pain. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Influence of storage environment, maturity stage and pre-storage disinfection treatments on tomato fruit quality during winter in KwaZulu-Natal, South Africa.

    PubMed

    Tolesa, G N; Workneh, T S

    2017-09-01

    The aim of this study was to explore influence of evaporative cooling (EC), pre-storage disinfection treatments and maturity stage at harvest on postharvest quality of tomato fruit. The tomato samples ( Lycopersicon esculentum Mill. cv. Nemonetta) were harvested, stored for 28 days and data were collected every seven days. The pH, total titratable acidity (TTA), total soluble solids (TSS), firmness, colour, weight loss (PWL) and marketability percentage were analysed. The temperature difference between ambient storage and EC at the fan varied between 4 and 7 °C, the relative humidity (RH) varied between 31 and 86%, while at different locations inside the EC it varied between 2-3 °C and 5-8%, respectively. Maturity had significant influence on the overall quality of tomatoes. The pH value of green, pink and red tomato was 4.86 and 5.03. The TTA content, the TSS content significantly affected over the 14 days of storage. TSS:TA was found to be in the range of 7.8-33.9. The EC storage shows a higher firmness and hue angle, when compared to the ambient conditions stored tomatoes. Compared to ambient storage, EC storage reduced the PWL by 7-10% over 30 days, while ambient storage took 15 days. EC storage and pre-storage treatments improved the shelf-life and marketability of tomatoes. However, variation in temperature and RH inside EC could affect the storability of the produce.

  16. Nitrogen requirements of commercial wine yeast strains during fermentation of a synthetic grape must.

    PubMed

    Gutiérrez, Alicia; Chiva, Rosana; Sancho, Marta; Beltran, Gemma; Arroyo-López, Francisco Noé; Guillamon, José Manuel

    2012-08-01

    Nitrogen deficiencies in grape musts are one of the main causes of stuck or sluggish wine fermentations. Currently, the most common method for dealing with nitrogen-deficient fermentations is adding supplementary nitrogen (usually ammonium phosphate). However, it is important to know the specific nitrogen requirement of each strain, to avoid excessive addition that can lead to microbial instability and ethyl carbamate accumulation. In this study, we aimed to determine the effect of increasing nitrogen concentrations of three different nitrogen sources on growth and fermentation performance in four industrial wine yeast strains. This task was carried out using statistical modeling techniques. The strains PDM and RVA showed higher growth-rate and maximum population size and consumed nitrogen much more quickly than strains ARM and TTA. Likewise, the strains PDM and RVA were also the greatest nitrogen demanders. Thus, we can conclude that these differences in nitrogen demand positively correlated with higher growth rate and higher nitrogen uptake rate. The most direct effect of employing an adequate nitrogen concentration is the increase in biomass, which involves a higher fermentation rate. However, the impact of nitrogen on fermentation rate is not exclusively due to the increase in biomass because the strain TTA, which showed the worst growth behavior, had the best fermentation activity. Some strains may adapt a strategy whereby fewer cells with higher metabolic activity are produced. Regarding the nitrogen source used, all the strains showed the better and worse fermentation performance with arginine and ammonium, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Virtual Reality as a Medium for Sensorimotor Adaptation Training and Spaceflight Countermeasures

    NASA Technical Reports Server (NTRS)

    Madansingh, S.; Bloomberg, J. J.

    2015-01-01

    With the upcoming shift to extra-long duration missions (1 year) aboard the ISS, sensorimotor adaptations during transitory periods in-and-out of microgravity are more important to understand and prepare for. Advances in virtual reality technology enables everyday adoption of these tools for entertainment and use in training. Experiencing virtual environments (VE) allows for the manipulation of visual flow to elicit automatic motor behavior and produce sensorimotor adaptation (SA). Recently, the ability to train individuals using repeatable and varied exposures to SA challenges has shown success by improving performance during exposure to a novel environment (Batson 2011). This capacity to 'learn to learn' is referred to as sensorimotor adaptive generalizability and, through the use of treadmill training, represents an untapped potential for individualized countermeasures. The goal of this study is to determine the feasibility of present head mounted displays (HMDs) to produce compelling visual flow information and the expected adaptations for use in future SA treadmill-based countermeasures. Participants experience infinite hallways providing congruent (baseline) or incongruent visual information (half or double speed) via HMD while walking on an instrumented treadmill at 1.1m/s. As gait performance approaches baseline levels, an adaptation time constant is derived to establish individual time-to-adapt (TTA). It is hypothesized that decreasing the TTA through SA treadmill training will facilitate sensorimotor adaptation during gravitational transitions. In this way, HMD technology represents a novel platform for SA training using off-the-shelf consumer products for greater training flexibility in astronaut and terrestrial applications alike.

  18. Strategy Toward the Total Synthesis of Epothilones A and B

    DTIC Science & Technology

    1999-07-01

    2-(iV-morpholino)ethanesulfonic acid ). 1 mM EGTA(1.2-di(2-aminoethoxy)ethane-/V..V..V’.Af’-tetraaceticacid). 0.5 mM MgCl2, 1 mM GTP. and 3 M... acid ), 1 mM EGTA. 0.5 nM MgCU. ImM GTP and 3M glyceropH £6- Tta concentration of tubulin in MTP was estimated to be about 85%. Assembly was...fragment projected for the olefin metathesis step. For this purpose, it would be appropriate to reach a carboxylic acid (cf. 28, Scheme 4) for

  19. Photocatalytic CO 2 Reduction by Trigonal-Bipyramidal Cobalt(II) Polypyridyl Complexes: The Nature of Cobalt(I) and Cobalt(0) Complexes upon Their Reactions with CO 2, CO, or Proton

    DOE PAGES

    Shimoda, Tomoe; Morishima, Takeshi; Kodama, Koichi; ...

    2018-04-26

    Trigonal-bipyramidal Co(II) complexes are used for photochemical carbon dioxide (CO 2) reduction with Ru(bpy) 3 2+ as a photosensitizer, tri-p-tolylamine (TTA) as a reversible quencher, and triethylamine (TEA) as a sacrificial electron donor to produce carbon monoxide and dihydrogen. Here, the CO 2 reduction is slow because of the large structural changes, spin flipping in the cobalt catalytic intermediates, and an uphill reaction for reduction to catalytically active Co(0) by the photoproduced [Ru(bpy) 3] +.

  20. Photocatalytic CO 2 Reduction by Trigonal-Bipyramidal Cobalt(II) Polypyridyl Complexes: The Nature of Cobalt(I) and Cobalt(0) Complexes upon Their Reactions with CO 2, CO, or Proton

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shimoda, Tomoe; Morishima, Takeshi; Kodama, Koichi

    Trigonal-bipyramidal Co(II) complexes are used for photochemical carbon dioxide (CO 2) reduction with Ru(bpy) 3 2+ as a photosensitizer, tri-p-tolylamine (TTA) as a reversible quencher, and triethylamine (TEA) as a sacrificial electron donor to produce carbon monoxide and dihydrogen. Here, the CO 2 reduction is slow because of the large structural changes, spin flipping in the cobalt catalytic intermediates, and an uphill reaction for reduction to catalytically active Co(0) by the photoproduced [Ru(bpy) 3] +.

  1. Calcium Channels in Postnatal Development of Rat Pancreatic Beta Cells and Their Role in Insulin Secretion

    PubMed Central

    García-Delgado, Neivys; Velasco, Myrian; Sánchez-Soto, Carmen; Díaz-García, Carlos Manlio; Hiriart, Marcia

    2018-01-01

    Pancreatic beta cells during the first month of development acquire functional maturity, allowing them to respond to variations in extracellular glucose concentration by secreting insulin. Changes in ionic channel activity are important for this maturation. Within the voltage-gated calcium channels (VGCC), the most studied channels are high-voltage-activated (HVA), principally L-type; while low-voltage-activated (LVA) channels have been poorly studied in native beta cells. We analyzed the changes in the expression and activity of VGCC during the postnatal development in rat beta cells. We observed that the percentage of detection of T-type current increased with the stage of development. T-type calcium current density in adult cells was higher than in neonatal and P20 beta cells. Mean HVA current density also increased with age. Calcium current behavior in P20 beta cells was heterogeneous; almost half of the cells had HVA current densities higher than the adult cells, and this was independent of the presence of T-type current. We detected the presence of α1G, α1H, and α1I subunits of LVA channels at all ages. The Cav 3.1 subunit (α1G) was the most expressed. T-type channel blockers mibefradil and TTA-A2 significantly inhibited insulin secretion at 5.6 mM glucose, which suggests a physiological role for T-type channels at basal glucose conditions. Both, nifedipine and TTA-A2, drastically decreased the beta-cell subpopulation that secretes more insulin, in both basal and stimulating glucose conditions. We conclude that changes in expression and activity of VGCC during the development play an important role in physiological maturation of beta cells. PMID:29556214

  2. A quantitative real-time PCR assay for the detection of tetR of Tn10 in Escherichia coli using SYBR Green and the Opticon.

    PubMed

    Morsczeck, Christian; Langendörfer, Daniel; Schierholz, Jörg Michael

    2004-06-30

    Bacteria of implant infections are extremely resistant to antibiotics. One reason for this antibiotic resistance are transposons; the well-known transposon Tn10, for example, mediates tetracycline resistance to Escherichia coli. Two genes of Tn10, tetA and tetR, are essential for the mechanism of resistance. These genes encode a drug-specific efflux protein and a tetracycline repressor protein, respectively. Tn10 is also widely used in molecular biology. For example, tTA, a recombinant derivate of tetR, has been utilised for a highly efficient gene regulation system in mammalian cells. We have examined E. coli isolates from implant infections for tetracycline resistance and for the presence of tetR. A real-time PCR assay was developed for detection of tetR with SybrGreen using the Opticon PCR machine of MJ Research. This method offers a quick, sensitive, efficient, and reliable approach to the detection and quantification of genes. Clinical isolates of E. coli were examined successfully for tetracycline resistance and for the presence of tetR. The real-time PCR is effective using a variety of templates including isolated E. coli DNA, pure colonies, or liquid culture sources. Using quantified standard DNA, this assay can accurately detect as few as 15 copies. Moreover, this assay has the ability to quantify the number of tetR genes in the presence of contaminating mammalian DNA. In conclusion, the tetR real-time PCR offers new methods for detection and quantification of tetracycline-resistant bacteria and tTA in transfected cell-lines or transgenic animals.

  3. Management of Candida guilliermondii joint infection in a dog.

    PubMed

    Bufalari, Antonello; Maggio, Chiara; Moretti, Giulia; Crovace, Alberto; Stefanetti, Valentina; Straubinger, Reinhard Konrad; Passamonti, Fabrizio

    2016-07-08

    Candida spp. are dimorphic fungi in the family Cryptococcaceae. Infections with Candida spp. are usually rare conditions in dogs, but immunocompromised patients have a higher risk for developing invasive candidal infections. A 5-year-old male Boxer, positive to Leishmania infantum, was referred to the Veterinary Teaching Hospital of the Department of Veterinary Medicine, University of Perugia, Italy for examination of a non-weight bearing left hind limb lameness of a duration of at least 3 months. During this period, treatment involved systemic anti-inflammatory medications and intra-articular corticosteroid administration. On presentation, clinical examination and radiographic findings were suggestive of cranial cruciate ligament deficiency. To support this diagnosis a stifle arthroscopy was performed: it confirmed a partial rupture of cranial cruciate ligament. Samples culture of synovial fluid and membrane was routinely collected as well, and revealed Candida guilliermondii joint infection. Treatment for the C. guilliermondii joint infection involved systemic anti-fungal therapy, joint lavage and intra-articular administration of antifungal drugs. Lameness improved markedly during this treatment, but lameness did not resolve completely, probably due to cranial cruciate ligament deficiency. Tibial tuberosity advancement (TTA) was chosen in order to treat stifle instability and was performed 4 weeks following cessation of treatment of the C. guilliermondii joint infection. Six month after TTA the dog showed a completely recovery with no lameness. To the authors' knowledge, this is the first case of Candida spp. joint infection reported in dogs. The cause of the progression of the joint C. guilliermondii infection remains unclear but it may be associated with leishmaniasis or intra-articular corticosteroid injections. Treatment with systemic and intra-articular anti-fungal therapies was successful. In the evaluation of hind limb lameness in a chronically immunocompromised dog, it would be advisable to consider also an intra-articular Candida spp.

  4. Perspective on the combined use of an independent transgenic sexing and a multifactorial reproductive sterility system to avoid resistance development against transgenic Sterile Insect Technique approaches

    PubMed Central

    2014-01-01

    Background The Sterile Insect Technique (SIT) is an accepted species-specific genetic control approach that acts as an insect birth control measure, which can be improved by biotechnological engineering to facilitate its use and widen its applicability. First transgenic insects carrying a single killing system have already been released in small scale trials. However, to evade resistance development to such transgenic approaches, completely independent ways of transgenic killing should be established and combined. Perspective Most established transgenic sexing and reproductive sterility systems are based on the binary tTA expression system that can be suppressed by adding tetracycline to the food. However, to create 'redundant killing' an additional independent conditional expression system is required. Here we present a perspective on the use of a second food-controllable binary expression system - the inducible Q system - that could be used in combination with site-specific recombinases to generate independent transgenic killing systems. We propose the combination of an already established transgenic embryonic sexing system to meet the SIT requirement of male-only releases based on the repressible tTA system together with a redundant male-specific reproductive sterility system, which is activated by Q-system controlled site-specific recombination and is based on a spermatogenesis-specifically expressed endonuclease acting on several species-specific target sites leading to chromosome shredding. Conclusion A combination of a completely independent transgenic sexing and a redundant reproductive male sterility system, which do not share any active components and mediate the induced lethality by completely independent processes, would meet the 'redundant killing' criteria for suppression of resistance development and could therefore be employed in large scale long-term suppression programs using biotechnologically enhanced SIT. PMID:25471733

  5. Differentiation of Gemella haemolysans (Thjøtta and Bøe 1938) Berger 1960, from Streptococcus morbillorum (Prevot 1933) Holdeman and Moore 1974.

    PubMed

    Berger, U; Pervanidis, A

    1986-05-01

    Recently, G. haemolysans and S. morbillorum were postulated to be identical organisms, so that consequently their names were synonyms. In the present paper it was demonstrated, that, in spite of many similarities, both species can be differentiated by nitrite reduction, lacking in S. morbillorum, and some further enzymatic activities as well as by antigenic specificity and certain dissimilarities in morphology, growth conditions and their ability to induce beta-hemolysis. S. morbillorum apparently represents a group of strains with divergent properties and might be assigned to the genus Gemella rather than to Streptococcus.

  6. Final Environmental Assessment/Overseas Environmental Assessment Joint Strile Fighter System Development and Demonstration Developmental Test Program

    DTIC Science & Technology

    2007-01-01

    tte r t es t a...ct iv iti es . Pr op os ed p er fo rm an ce te st s w ou ld c oi nc id e w ith F Q , f lu tte r, hi gh A ng le -o f- A tta ck ( A oA ), an...cl os el y in te gr at ed w ith th e FQ , f lu tte r, an d hi gh A oA te st s a nd w ou ld g en er al ly p ro ce ed in c on ce rt

  7. Identification and Characterization of Ovarian Carcinoma Peptide Epitopes Recognized by Cytotoxic T Lymphocytes

    DTIC Science & Technology

    2007-11-01

    CCA CAG TGC CCC AGG TTA GAA CGG TCA GCA GAA TAG-2a 62 528 AGC GGC GGG CTG AAG GA GAG GGT AGG GTG GTC ATT GTG TCA TAG-2b 62 401 AGC GGC GGG CTG AAG...GGT AGG GTG GTC ATT GTG TCA TAG-2b 62 401 AGC GGC GGG CTG AAG GAC TC CAG CAC AAC AGG AAC ATT CAG TGG TAB-2c 62 536 AGC GGC GGG CTG AAG GA GGG GGA TTT...Makrigiannakis A, Gray H, Schlienger K, Liebman MN, Rubin SC, Coukos G (2003) Intratumoral T cells, recurrence, and survival in epithelial ovarian

  8. The 1984 ARI Survey of Army Recruits: Codebook for October 84/February 85 USAR (U.S. Army Reserve) and ARNG (Army National Guard) Survey Respondents

    DTIC Science & Technology

    1986-05-01

    I 1 ICHECKED -IN OTHER PARTS OF A NEWSPAPER 1290 --- _ _ _ _I__ _ _ _ __ __ _ __ _ __ _ __ 120I 100.0 TTA I 1 1 A I B I C I D T 11982 1198317 IN I__...FREQ I PERCENT I VALUE I MEANING ___ I _ _ _ I _ _ _ __ __1_ __ _ _ _ _ _8 1 0.6 1 . I NO RESPONSE 768 1 59.5 1 0 1 NOT CHECKED 514 I39.8 I 1 ICHECKED ...27 1 2.1 1 1 ICHECKED - BOOKLET ABOUT ARMY COLLEGE FUND 1290 1 100.0 I T-OTALSI TO CHECK FOR OUT OF RANGE VALUES FOR THIS ’MARK ALL THAT APPLY

  9. Limb Salvage After Failed Initial Operative Management of Bimalleolar Ankle Fractures in Diabetic Neuropathy.

    PubMed

    Vaudreuil, Nicholas J; Fourman, Mitchell S; Wukich, Dane K

    2017-03-01

    Ankle fractures in patients with diabetes mellitus (DM) can be difficult to manage, especially in the presence of peripheral neuropathy. In patients who fail initial operative management, attempts at limb salvage can be challenging, and no clear treatment algorithm exists. This study examined outcomes of different procedures performed for limb salvage in this population. This study retrospectively reviewed 17 patients with DM complicated by peripheral neuropathy who sustained a bimalleolar ankle fracture and failed initial operative management. Patients were treated with revision open reduction internal fixation (ORIF) (3/17), closed reduction external fixation (CREF) (8/17), or primary ankle joint fusion (3/17 tibiotalocalcaneal fusion with hindfoot nail [TTCN] and 3/17 with tibiotalar arthrodesis using plates and screws [TTA]). Median follow-up was 20 months. The overall rate of limb salvage was 82.3% (14/17). All patients who went on to amputation presented with infection and were treated initially with CREF (3/3). All patients who achieved successful limb salvage ended up with a clinically fused ankle joint (14/14); 9 underwent a primary or delayed formal fusion and 5 had a clinically fused ankle joint at study conclusion after undergoing revision ORIF or CREF with adjunctive procedures. This small study suggests that in this complicated group of patients it is difficult to achieve limb salvage with an end result of a functional ankle joint. CREF can be a viable option in cases where underlying infection or poor bone quality is present. Treatment with revision ORIF frequently requires supplementary external fixator or tibiotalar Steinman pin placement for additional stability. All patients who underwent revision ORIF ended up with clinically fused ankle joints at the end of the study period. Primary fusion procedures (TTA, TTCN) were associated with a high rate of limb salvage and a decreased number of operations. Level III, retrospective case series.

  10. Erosive and cariogenicity potential of pediatric drugs: study of physicochemical parameters

    PubMed Central

    2013-01-01

    Background Pediatric medications may possess a high erosive potential to dental tissues due to the existence of acid components in their formulations. The purpose was to determine the erosive and cariogenic potential of pediatric oral liquid medications through the analysis of their physicochemical properties in vitro. Methods A total of 59 substances were selected from the drug reference list of the National Health Surveillance Agency (ANVISA), which belong to 11 therapeutic classes, as follows: analgesics, non-steroidal anti-inflammatory, corticosteroids, antihistamines, antitussives, bronchodilators, antibacterials, antiparasitics, antiemetics, anticonvulsants and antipsychotics. Measurement of pH was performed by potentiometry, using a digital pH meter. For the Total Titratable Acidity (TTA) chemical assay, a 0.1 N NaOH standard solution was used, which was titrated until drug pH was neutralized. The Total Soluble Solids Contents (TSSC) quantification was carried out by refractometry using Brix scale and the analysis of Total Sugar Content was performed according to Fehling’s method. In addition, it was analyzed the information contained in the drug inserts with regard to the presence of sucrose and type of acid and sweetener added to the formulations. Results All drug classes showed acidic pH, and the lowest mean was found for antipsychotics (2.61 ± 0.08). There was a large variation in the TTA (0.1% - 1.18%) and SST (10.44% - 57.08%) values. High total sugar contents were identified in the antitussives (53.25%) and anticonvulsants (51.75%). As described in the drug inserts, sucrose was added in 47.5% of the formulations, as well as citric acid (39.0%), sodium saccharin (36.4%) and sorbitol (34.8%). Conclusion The drugs analyzed herein showed physicochemical characteristics indicative of a cariogenic and erosive potential on dental tissues. Competent bodies’ strategies should be implemented in order to broaden the knowledge of health professionals, drug manufacturers and general consuming public about the risks from the consumption of medicines potentially harmful to dental tissues. PMID:24325544

  11. Erosive and cariogenicity potential of pediatric drugs: study of physicochemical parameters.

    PubMed

    Xavier, Alidianne Fábia C; Moura, Eline F F; Azevedo, Waldeneide F; Vieira, Fernando F; Abreu, Mauro H N G; Cavalcanti, Alessandro L

    2013-12-10

    Pediatric medications may possess a high erosive potential to dental tissues due to the existence of acid components in their formulations. The purpose was to determine the erosive and cariogenic potential of pediatric oral liquid medications through the analysis of their physicochemical properties in vitro. A total of 59 substances were selected from the drug reference list of the National Health Surveillance Agency (ANVISA), which belong to 11 therapeutic classes, as follows: analgesics, non-steroidal anti-inflammatory, corticosteroids, antihistamines, antitussives, bronchodilators, antibacterials, antiparasitics, antiemetics, anticonvulsants and antipsychotics. Measurement of pH was performed by potentiometry, using a digital pH meter. For the Total Titratable Acidity (TTA) chemical assay, a 0.1 N NaOH standard solution was used, which was titrated until drug pH was neutralized. The Total Soluble Solids Contents (TSSC) quantification was carried out by refractometry using Brix scale and the analysis of Total Sugar Content was performed according to Fehling's method. In addition, it was analyzed the information contained in the drug inserts with regard to the presence of sucrose and type of acid and sweetener added to the formulations. All drug classes showed acidic pH, and the lowest mean was found for antipsychotics (2.61 ± 0.08). There was a large variation in the TTA (0.1% - 1.18%) and SST (10.44% - 57.08%) values. High total sugar contents were identified in the antitussives (53.25%) and anticonvulsants (51.75%). As described in the drug inserts, sucrose was added in 47.5% of the formulations, as well as citric acid (39.0%), sodium saccharin (36.4%) and sorbitol (34.8%). The drugs analyzed herein showed physicochemical characteristics indicative of a cariogenic and erosive potential on dental tissues. Competent bodies' strategies should be implemented in order to broaden the knowledge of health professionals, drug manufacturers and general consuming public about the risks from the consumption of medicines potentially harmful to dental tissues.

  12. The triplet excited state of Bodipy: formation, modulation and application.

    PubMed

    Zhao, Jianzhang; Xu, Kejing; Yang, Wenbo; Wang, Zhijia; Zhong, Fangfang

    2015-12-21

    Boron dipyrromethene (Bodipy) is one of the most extensively investigated organic chromophores. Most of the investigations are focused on the singlet excited state of Bodipy, such as fluorescence. In stark contrast, the study of the triplet excited state of Bodipy is limited, but it is an emerging area, since the triplet state of Bodipy is tremendously important for several areas, such as the fundamental photochemistry study, photodynamic therapy (PDT), photocatalysis and triplet-triplet annihilation (TTA) upconversion. The recent developments in the study of the production, modulation and application of the triplet excited state of Bodipy are discussed in this review article. The formation of the triplet state of Bodipy upon photoexcitation, via the well known approach such as the heavy atom effect (including I, Br, Ru, Ir, etc.), and the new methods, such as using a spin converter (e.g. C60), charge recombination, exciton coupling and the doubly substituted excited state, are summarized. All the Bodipy-based triplet photosensitizers show strong absorption of visible or near IR light and the long-lived triplet excited state, which are important for the application of the triplet excited state in PDT or photocatalysis. Moreover, the methods for switching (or modulation) of the triplet excited state of Bodipy were discussed, such as those based on the photo-induced electron transfer (PET), by controlling the competing Förster-resonance-energy-transfer (FRET), or the intermolecular charge transfer (ICT). Controlling the triplet excited state will give functional molecules such as activatable PDT reagents or molecular devices. It is worth noting that switching of the singlet excited state and the triplet state of Bodipy may follow different principles. Application of the triplet excited state of Bodipy in PDT, hydrogen (H2) production, photoredox catalytic organic reactions and TTA upconversion were discussed. The challenges and the opportunities in these areas were briefly discussed.

  13. Annihilation limit of a visible-to-UV photon upconversion composition ascertained from transient absorption kinetics.

    PubMed

    Deng, Fan; Blumhoff, Jörg; Castellano, Felix N

    2013-05-30

    Noncoherent sensitized green-to-near-visible upconversion has been achieved utilizing palladium(II) octaethylporphyrin (PdOEP) as the triplet sensitizer and anthracene as the energy acceptor/annihilator in vacuum degassed toluene. Selective 547 nm excitation of PdOEP with incident irradiance as low as 600 μW/cm(2) results in the observation of anthryl fluorescence at higher energy. Stern-Volmer analysis of the dynamic phosphorescence quenching of PdOEP by anthracene possesses an extremely large K(SV) of 810,000 M(-1), yielding a triplet-triplet energy transfer quenching constant of 3.3 × 10(9) M(-1) s(-1). Clear evidence for the subsequent triplet-triplet annihilation (TTA) of anthracene was afforded by numerous experiments, one of the most compelling was an excitation scan illustrating that the Q-band absorption features of PdOEP are solely responsible for sensitizing the anti-Stokes fluorescence. The upconverted emission intensity with respect to the excitation power was shown to vary between quadratic and linear using either coherent or noncoherent light sources, illustrating the expected kinetic limits for the light producing photochemistry under continuous wave illumination. Time-resolved experiments directly comparing the total integrated anthracene intensity/time fluorescence data produced through upconversion (λ(ex) = 547 nm, delayed signal) and with direct excitation (λ(ex) = 355 nm, prompt signal) under conditions where the laser pulse is completely absorbed by the sample reveal annihilation efficiencies of approximately 40%. Similarly, the delayed fluorescence kinetic analysis reported by Schmidt and co-workers (J. Phys. Chem. Lett. 2010, 1, 1795-1799) was used to reveal the maximum possible efficiency from a model red-to-yellow upconverting composition and this treatment was applied to the anthryl triplet absorption decay transients of anthracene measured for the PdOEP/anthracene composition at 430 nm. From this analysis approximately 50% of the anthryl triplets that decay by TTA produce singlet fluorescence, consistent with the notion that annihilation spin statistics does not impose efficiency limits on upconversion photochemistry.

  14. Yellow emitting Iridium (III) phenyl-benzothiazole complexes with different β-diketone ancillary ligands as dopants in white organic light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Ivanov, P.; Petrova, P.; Tomova, R.

    2018-03-01

    We discuss the influence of the type of β-diketone ancillary ligand in Iridium (III) bis phenyl-benzothiazole complexes ((bt)2Ir(β-diketone)) on their photophysical and electroluminescent properties when they are used as dopants in white organic light-emitting diodes (WOLED). For this purpose, we investigated four novel yellow cyclometalated complexes: (bt)2Ir(dbm), (bt)2Ir(fmtdbm), (bt)2Ir(tta) and (bt)2Ir(bsm), where dbm = 1,3-diphenylpropane-1,3-dionate; fmtdbm = 1-(4-fluorophenyl)-3-(4-methoxyphenyl)propane-1,3-dionate; tta = 4,4,4-trifluoro-1-(thiophene-2-yl)butane-1,3-dionate; and bsm = 1-phenylicosane-1,3-dionate). To obtain white light by mixing emissions of two complementary colors (yellow emitted by the dopant and blue, by another emitter), we chose the following OLED structure: ITO/doped HTL/ElL/ETL/M, where ITO was a transparent anode of In2O3:SnO2; M, a metallic Al cathode; HTL, 4,4’-Bis(9H-carbazol-9-yl)biphenyl (CBP) involved in a poly(N-vinylcarbazole) (PVK) matrix; ElL, an electroluminescent layer of aluminum(III)bis(2-methyl-8-quninolinato)-4-phenylphenolate (BAlq); and ETL, an electron-transporting layer of zinc(II)bis(2-2-hydroxyphenyl)benzothiazole. We found that all complexes are suitable candidates for fabrication of WOLED. The best results were demonstrated by the device doped with 2 wt % of (bt)2Ir(bsm), which had twice as high luminescence (1100 cd/m2) and one-and-a-half as high current efficiency (5 cd/A) as the device doped with 1.25 wt % of the known (bt)2Ir(acac), with its 580 cd/m2 and 3.4 cd/A at approximately the same CIE (Commission Internationale de L’Eclairage) (x/y) coordinates of the warm white light emitted by the two devices.

  15. Summary of Current and Future MSFC International Space Station Environmental Control and Life Support System Activities

    NASA Technical Reports Server (NTRS)

    Ray, Charles D.; Carrasquillo, Robyn L.; Minton-Summers, Silvia

    1997-01-01

    This paper provides a summary of current work accomplished under technical task agreement (TTA) by the Marshall Space Flight Center (MSFC) regarding the Environmental Control and Life Support System (ECLSS) as well as future planning activities in support of the International Space Station (ISS). Current activities include ECLSS computer model development, component design and development, subsystem integrated system testing, life testing, and government furnished equipment delivered to the ISS program. A long range plan for the MSFC ECLSS test facility is described whereby the current facility would be upgraded to support integrated station ECLSS operations. ECLSS technology development efforts proposed to be performed under the Advanced Engineering Technology Development (AETD) program are also discussed.

  16. Effect of growth parameters on crystallinity and properties of ZnO films grown by plasma assisted MOCVD

    NASA Astrophysics Data System (ADS)

    Losurdo, M.; Giangregorio, M. M.; Sacchetti, A.; Capezzuto, P.; Bruno, G.; Malandrino, G.; Fragalà, I. L.

    2007-07-01

    Thin films of ZnO have been grown by plasma assisted metal-organic chemical vapour deposition (PA-MOCVD) using a 13.56 MHz O 2 plasma and the Zn(TTA)•tmed (HTTA=2-thenoyltrifluoroacetone, TMED=N,N,N',N'-tetramethylethylendiamine) precursor. The effects of growth parameters such as the plasma activation, the substrate, the surface temperature, and the ratio of fluxes of precursors on the structure, morphology, and optical and electrical properties of ZnO thin films have been studied. Under a very low plasma power of 20 W, c-axis oriented hexagonal ZnO thin films are grown on hexagonal sapphire (0001), cubic Si(001) and amorphous quartz substrates. The substrate temperature mainly controls grain size.

  17. Failure Analysis of CCD Image Sensors Using SQUID and GMR Magnetic Current Imaging

    NASA Technical Reports Server (NTRS)

    Felt, Frederick S.

    2005-01-01

    During electrical testing of a Full Field CCD Image Senor, electrical shorts were detected on three of six devices. These failures occurred after the parts were soldered to the PCB. Failure analysis was performed to determine the cause and locations of these failures on the devices. After removing the fiber optic faceplate, optical inspection was performed on the CCDs to understand the design and package layout. Optical inspection revealed that the device had a light shield ringing the CCD array. This structure complicated the failure analysis. Alternate methods of analysis were considered, including liquid crystal, light and thermal emission, LT/A, TT/A SQUID, and MP. Of these, SQUID and MP techniques were pursued for further analysis. Also magnetoresistive current imaging technology is discussed and compared to SQUID.

  18. The Role of the Hendra Virus and Nipah Virus Attachment Glycoproteins in Receptor Binding and Antibody Neutralization

    DTIC Science & Technology

    2014-01-31

    portions of the NiV-sG sequence on the 5’ ends (c: 5’- CGG AAG CTG ATG AAG CAG ATC GAG GAC-3’ , d: 5’-CTG GTG TAC TT CTT GAT CCT GGC CAG-3’). The leader...template-pcDNA-GCN(tet)-HeV-sG, forward primer: 5’- GTG GAG ATC TAC AAC ACC GGC GAC TC-3’ and reverse primer: 5’- GAG TCG CCG GTG TTG TAG ATC TCC AC-3...CCC CGC TCC GTG GCA ATA TTA CTA CTA C YA YAAHPS GAG CAG TAC GCC GCC CAT CCG TCC C F/L/W FAPHLW G TTC GCC CCC CAT CTG TGG CAA TAT TAC TAC TAC

  19. Technicians test OV-102's aft fuselage LRU hydrogen recirculation pump

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Donald C. Buckner, a Lockheed mechanical lead technician, installs an aft fuselage line replaceable unit (LRU) liquid hydrogen recirculation pump from Columbia, Orbiter Vehicle (OV) 102 into JSC's Thermochemical Test Area (TTA) Support Laboratory Bldg 350 test stand. Technicians ran the pump package through the battery of leak tests. Preliminary indications showed only minor, acceptable leakage from the package and Kennedy Space Center (KSC) technicians have replaced a crushed seal on the prevalve of the main propulsion system they believe may have caused the STS-35 hydrogen leak. In addition to Buckner, (left to right) Larry Kilbourn, a Rockwell Service Center lead mechanical technician from Cape Canaveral, and John Dickerson, a quality inspector with EBASCO Services, also monitored the test at JSC. Photo taken by JSC photographer Benny Benavides.

  20. Analysis of Knee Joint Line Obliquity after High Tibial Osteotomy.

    PubMed

    Oh, Kwang-Jun; Ko, Young Bong; Bae, Ji Hoon; Yoon, Suk Tae; Kim, Jae Gyoon

    2016-11-01

    The aim of this study was to evaluate which lower extremity alignment (knee and ankle joint) parameters affect knee joint line obliquity (KJLO) in the coronal plane after open wedge high tibial osteotomy (OWHTO). Overall, 69 knees of patients that underwent OWHTO were evaluated using radiographs obtained preoperatively and from 6 weeks to 3 months postoperatively. We measured multiple parameters of knee and ankle joint alignment (hip-knee-ankle angle [HKA], joint line height [JLH], posterior tibial slope [PS], femoral condyle-tibial plateau angle [FCTP], medial proximal tibial angle [MPTA], mechanical lateral distal femoral angle [mLDFA], KJLO, talar tilt angle [TTA], ankle joint obliquity [AJO], and the lateral distal tibial ground surface angle [LDTGA]; preoperative [-pre], postoperative [-post], and the difference between -pre and -post values [-Δ]). We categorized patients into two groups according to the KJLO-post value (the normal group [within ± 4 degrees, 56 knees] and the abnormal group [greater than ± 4 degrees, 13 knees]), and compared their -pre parameters. Multiple logistic regression analysis was used to examine the contribution of the -pre parameters to abnormal KJLO-post. The mean HKA-Δ (-9.4 ± 4.7 degrees) was larger than the mean KJLO-Δ (-2.1 ± 3.2 degrees). The knee joint alignment parameters (the HKA-pre, FCTP-pre) differed significantly between the two groups ( p  < 0.05). In addition, the HKA-pre (odds ratio [OR] = 1.27, p  = 0.006) and FCTP-pre (OR = 2.13, p  = 0.006) were significant predictors of abnormal KJLO-post. However, -pre ankle joint parameters (TTA, AJO, and LDTGA) did not differ significantly between the two groups and were not significantly associated with the abnormal KJLO-post. The -pre knee joint alignment and knee joint convergence angle evaluated by HKA-pre and FCTP-pre angle, respectively, were significant predictors of abnormal KJLO after OWHTO. However, -pre ankle joint parameters were not significantly associated with abnormal KJLO after OWHTO. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  1. Null Filter Mobile Radar (NFMRAD): Concept Verification,

    DTIC Science & Technology

    1980-10-01

    i ~ I t\\-~~iA \\-ti mitt Ir t!1 iil -it i 5 sh, \\ iIi : oil I III j tta i I, l I i i 1 :2)1 cfi i Iu ,ft vli tiiiht -ln r.t Anel t I ItIit ott!1 l vI...littIiS aI t ed )ki toe t I ( it I I, (t edsIn oil -u iletit ilthe li trilcoii, tile. I end 11c.d I [lht tx% t .I i Iii t ia Il (ila I s vst eli I S CS...appiiriate crrrectioin factors, and tiltitorrial iy~ oil pr’oc’edurec is c’rtliple’t. 17o calulat air antenna ratter, i’terall’t several I. to 1ii) ’i’reods

  2. Excitation of sensitized fluorescence of europium and curium in an aqueous solution of thenoyltrifluoroacetone by a nitrogen laser

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dem'yanova, T.A.; Stepanov, A.V.; Babaev, A.S.

    1987-03-01

    The fluorescence spectrum of trivalent europium in aqueous solutions of thenoyltrifluoroacetone, excited by a nitrogen laser with emission wavelength 337 nm, exhibits bands at 582, 593, 616, 650, and 695 nm. Two bands appear in the fluorescence spectrum of trivalent curium under the same conditions - at 598 and 607 nm. The times of quenching of the fluorescence of the ions of these elements were measured, both in H/sub 2/O medium and in D/sub 2/O. A linear relationship was found between the fluorescence intensity of europium and curium and their concentration in TTA solution. The limit of determination of europiummore » and curium by the fluorescent method with laser excitation using the bands at 615 and 607 nm proved equal to 0.3 and 0.07 ng/ml, respectively.« less

  3. A Comparison of Bus Architectures for Safety-Critical Embedded Systems

    NASA Technical Reports Server (NTRS)

    Rushby, John; Miner, Paul S. (Technical Monitor)

    2003-01-01

    We describe and compare the architectures of four fault-tolerant, safety-critical buses with a view to deducing principles common to all of them, the main differences in their design choices, and the tradeoffs made. Two of the buses come from an avionics heritage, and two from automobiles, though all four strive for similar levels of reliability and assurance. The avionics buses considered are the Honeywell SAFEbus (the backplane data bus used in the Boeing 777 Airplane Information Management System) and the NASA SPIDER (an architecture being developed as a demonstrator for certification under the new DO-254 guidelines); the automobile buses considered are the TTTech Time-Triggered Architecture (TTA), recently adopted by Audi for automobile applications, and by Honeywell for avionics and aircraft control functions, and FlexRay, which is being developed by a consortium of BMW, DaimlerChrysler, Motorola, and Philips.

  4. [Analysis of H63D mutation in hemochromatosis (HFE) gene in populations of central Eurasia].

    PubMed

    Khusainova, R I; Khusnutdinova, N N; Litvinov, S S; Khusnutdinova, E K

    2013-02-01

    An analysis of the frequency of H63D (c. 187C>G) mutations in the HFEgene in 19 populations from Central Eurasia demonstrated that the distribution of the mutation in the region of interest was not uniform and that there were the areas of H63D accumulation. The investigation of three polymorphic variants, c.340+4T>C (rs2071303, IVS2(+4)T>C), c.893-44T>C (rs1800708, IVS4(-44)T>C), and c.1007-47G>A (rs1572982, IVS5(-47)A>G), in the HFE gene in individuals homozygous for H63D mutations in the HFE gene revealed the linkage of H63D with three haplotypes, *CTA, *TG, and *TTA. These findings indicated the partial spread of the mutation in Central Eurasia from Western Europe, as well as the possible repeated appearance of the mutation on the territory on interest.

  5. Development of Technology Transfer Economic Growth Metrics

    NASA Technical Reports Server (NTRS)

    Mastrangelo, Christina M.

    1998-01-01

    The primary objective of this project is to determine the feasibility of producing technology transfer metrics that answer the question: Do NASA/MSFC technical assistance activities impact economic growth? The data for this project resides in a 7800-record database maintained by Tec-Masters, Incorporated. The technology assistance data results from survey responses from companies and individuals who have interacted with NASA via a Technology Transfer Agreement, or TTA. The goal of this project was to determine if the existing data could provide indications of increased wealth. This work demonstrates that there is evidence that companies that used NASA technology transfer have a higher job growth rate than the rest of the economy. It also shows that the jobs being supported are jobs in higher wage SIC codes, and this indicates improvements in personal wealth. Finally, this work suggests that with correct data, the wealth issue may be addressed.

  6. Word Frequency Analysis. MOS: 62J. Skill Levels 1 & 2.

    DTIC Science & Technology

    1981-05-01

    WCRDI COUNT2 W OR u, CO UIT 3 WORD 3 COUNT’. kCRD4 I CELL 9 CLNTER I CERERLINE t CENTRALLY 2 C [JTP I FGAL 2 CZRT..IN I CESSIVE 46 LFI’ 14 C H%1% ~ 4...4 .4* 4 AD ,G4 ANGLI 4 fC S 0A 4 r. 5 54b d204 4 BE- J 4OCK4 ECAGNE 4 TTA .(.KFTS 4 B𔃻E.KER 4 44 CC!’PPCT 4 13FL*.~If 4 CCLC CTwV7CCC~L< EL4 CO 4 CE...t CI RE I CARTcUL I CAR7~ I 3 CARRY I CAL 7I C!! 11 E t C., TFPS I CA~TCH I C4TEO I co usIN Kr I CL TC1 I CELL 1CTNlERL!NEz I ’ENI P.LIY Ic3VEI

  7. Realignment Surgery for Malunited Ankle Fracture.

    PubMed

    Guo, Chang-Jun; Li, Xing-Cheng; Hu, Mu; Xu, Yang; Xu, Xiang-Yang

    2017-02-01

    To investigate the characteristics and the results of realignment surgery for the treatment of malunited ankle fracture. Thirty-three patients with malunited fractures of the ankle who underwent reconstructive surgery at our hospital from January 2010 to January 2014 were reviewed. The tibial anterior surface angle (TAS), the tibiotalar tilt angle (TTA), the malleolar angle (MA), and the tibial lateral surface angle (TLS) were measured. Clinical assessment was performed with use of the American Orthopaedic Foot and Ankle Society (AOFAS) scale and visual analogue scale (VAS) scores, and the osteoarthritis stage was determined radiographically with the modified Takakura classification system. The Wilcoxon matched-pairs test was used to analyze the difference between the preoperative and the postoperative data. The mean follow-up was 36 months (range, 20-60 months). The mean age at the time of realignment surgery was 37.1 years (range, 18-62 years). Compared with preoperation, the TAS at the last follow-up showed a significant increase (88.50° ± 4.47° vs. 90.80° ± 3.49°, P = 0.0035); similar results were observed in TTA (1.62° ± 1.66° vs. 0.83° ± 0.90°, P < 0.01) and MA (82.30° ± 8.03° vs. 78.70° ± 4.76°, P = 0.005). At the last follow-up, the mean AOFAS score was significantly increased compared with the score at preoperation (44.5 ± 13.7 vs. 78.0 ± 8.9, P < 0.01). Significant differences in VAS scores were found at the last follow-up (6.76 ± 1.03 vs. 2.03 ± 1.21, P < 0.01). There was no significant difference in the Takakura grade between the preoperation and the last follow-up. One patient had increased talar tilt postsurgery; the postoperative talar tilt angle of this patient was 20°. One patient had progressive ankle osteoarthritis, and was treated by ankle joint distraction. Realignment surgery for a malunited ankle fracture can reduce pain, improve function, and delay ankle arthrodesis or total ankle replacement. Postoperative large talar tilt and advanced stages of ankle arthritis are the risk factors for the surgery. © 2017 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

  8. Long-lived room-temperature deep-red-emissive intraligand triplet excited state of naphthalimide in cyclometalated Ir(III) complexes and its application in triplet-triplet annihilation-based upconversion.

    PubMed

    Sun, Jifu; Wu, Wanhua; Zhao, Jianzhang

    2012-06-25

    Cyclometalated Ir(III) complexes with acetylide ppy and bpy ligands were prepared (ppy = 2-phenylpyridine, bpy = 2,2'-bipyridine) in which naphthal (Ir-2) and naphthalimide (NI) were attached onto the ppy (Ir-3) and bpy ligands (Ir-4) through acetylide bonds. [Ir(ppy)(3)] (Ir-1) was also prepared as a model complex. Room-temperature phosphorescence was observed for the complexes; both neutral and cationic complexes Ir-3 and Ir-4 showed strong absorption in the visible range (ε=39,600  M(-1)  cm(-1) at 402 nm and ε=25,100  M(-1)  cm(-1) at 404 nm, respectively), long-lived triplet excited states (τ(T)=9.30 μs and 16.45 μs) and room-temperature red emission (λ(em)=640 nm, Φ(p)=1.4 % and λ(em)=627 nm, Φ(p)=0.3 %; cf. Ir-1: ε=16,600  M(-1)  cm(-1) at 382 nm, τ(em)=1.16 μs, Φ(p)=72.6 %). Ir-3 was strongly phosphorescent in non-polar solvent (i.e., toluene), but the emission was completely quenched in polar solvents (MeCN). Ir-4 gave an opposite response to the solvent polarity, that is, stronger phosphorescence in polar solvents than in non-polar solvents. Emission of Ir-1 and Ir-2 was not solvent-polarity-dependent. The T(1) excited states of Ir-2, Ir-3, and Ir-4 were identified as mainly intraligand triplet excited states ((3)IL) by their small thermally induced Stokes shifts (ΔE(s)), nanosecond time-resolved transient difference absorption spectroscopy, and spin-density analysis. The complexes were used as triplet photosensitizers for triplet-triplet annihilation (TTA) upconversion and quantum yields of 7.1 % and 14.4 % were observed for Ir-2 and Ir-3, respectively, whereas the upconversion was negligible for Ir-1 and Ir-4. These results will be useful for designing visible-light-harvesting transition-metal complexes and for their applications as triplet photosensitizers for photocatalysis, photovoltaics, TTA upconversion, etc. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. The influence of nano-oxide layer on magnetostriction of sensing layer in bottom spin valves

    NASA Astrophysics Data System (ADS)

    Qiu, J. J.; Han, G. C.; Li, K. B.; Liu, Z. Y.; Zong, B. Y.; Wu, Y. H.

    2006-05-01

    The magnetostriction coefficient (λs) of ultrathin sputtered polycrystalline as-deposited and annealed Ta/Ni81Fe19(t)/Ta films was studied as a function of the thickness. λs and magnetoresistance (MR) of bottom-type spin valves (SVs) with nano-oxide layer (NOL) added in the pinned layer were investigated by using NiFe, Co90Fe10, and CoFe/NiFe/CoFe layers as free layer (FL), respectively. λs of SV with NOL increased slightly except that of CoFe FL. NOLs were added at different positions to study the effects of NOL on λs of CoFe FL. All λs of CoFe FL change from negative to positive and its absolute value also increases significantly with CoFeOx related NOL added below. Our λs and surface roughness results indicated that the structure of the film not the roughness dominates λs of ultrathin FL in SVs.

  10. Excitation energy transfer in europium chelate with doxycycline in the presence of a second ligand in micellar solutions of nonionic surfactants

    NASA Astrophysics Data System (ADS)

    Smirnova, T. D.; Shtykov, S. N.; Kochubei, V. I.; Khryachkova, E. S.

    2011-01-01

    The complexation of Eu3+ with doxycycline (DC) antibiotic in the presence of several second ligands and surfactant micelles of different types is studied by the spectrophotometric and luminescence methods. It is found that the efficiency of excitation energy transfer in Eu3+-DC chelate depends on the nature of the second ligand and surfactant micelles. Using thenoyltrifluoroacetone (TTA) as an example, it is shown that the second ligand additionally sensitizes the europium fluorescence, and the possibility of intermediate sensitization of DC and then of europium is shown by the example of 1,10-phenanthroline. In all cases, the excitation energy transfer efficiency was increased due to the so-called antenna effect. The decay kinetics of the sensitized fluorescence of the binary and mixed-ligand chelates in aqueous and micellar solutions of nonionic surfactants is studied and the relative quantum yields and lifetimes of fluorescence are determined.

  11. Preparation and luminescent properties of the novel polymer-rare earth complexes composed of Poly(ethylene-co-acrylic acid) and Europium ions

    NASA Astrophysics Data System (ADS)

    Wu, Yuewen; Hao, Haixia; Wu, Qingyao; Gao, Zihan; Xie, Hongde

    2018-06-01

    A series of novel polymer-rare earth complexes with Eu3+ ions have been synthesized and investigated successfully, including the binary complexes containing the single ligand poly(ethylene-co-acrylic acid) (EAA) and the ternary complexes using 1,10-phenanthroline (phen), dibenzoylmethane (DBM) or thenoyltrifluoroacetone (TTA) as the second ligand. Their structures have been characterized by Fourier transform infrared spectroscopy (FT-IR), elemental analysis and X-ray diffraction (XRD), which confirm that both EAA and small molecules participate in the coordination reaction with rare earth ions, and they can disperse homogeneously in the polymer matrixes. Both ultraviolet-visible (UV-vis) absorption and photoluminescence tests for the complexes have been recorded. The relationship between fluorescence intensity of polymer-rare earth complexes and the quantity of ligand EAA has been studied and discussed. The films casted from the complexes solution can emit strong characteristic red light under UV light excitation. All these results suggest that the complexes possess potential application as luminescent materials.

  12. Biocatalytic Conversion of Avermectin to 4"-Oxo-Avermectin: Heterologous Expression of the ema1 Cytochrome P450 Monooxygenase

    PubMed Central

    Molnár, István; Hill, D. Steven; Zirkle, Ross; Hammer, Philip E.; Gross, Frank; Buckel, Thomas G.; Jungmann, Volker; Pachlatko, Johannes Paul; Ligon, James M.

    2005-01-01

    The cytochrome P450 monooxygenase Ema1 from Streptomyces tubercidicus R-922 and its homologs from closely related Streptomyces strains are able to catalyze the regioselective oxidation of avermectin into 4"-oxo-avermectin, a key intermediate in the manufacture of the agriculturally important insecticide emamectin benzoate (V. Jungmann, I. Molnár, P. E. Hammer, D. S. Hill, R. Zirkle, T. G. Buckel, D. Buckel, J. M. Ligon, and J. P. Pachlatko, Appl. Environ. Microbiol. 71:6968-6976, 2005). The gene for Ema1 has been expressed in Streptomyces lividans, Streptomyces avermitilis, and solvent-tolerant Pseudomonas putida strains using different promoters and vectors to provide biocatalytically competent cells. Replacing the extremely rare TTA codon with the more frequent CTG codon to encode Leu4 in Ema1 increased the biocatalytic activities of S. lividans strains producing this enzyme. Ferredoxins and ferredoxin reductases were also cloned from Streptomyces coelicolor and biocatalytic Streptomyces strains and tested in ema1 coexpression systems to optimize the electron transport towards Ema1. PMID:16269733

  13. Electroluminescence of organic light-emitting diodes consisting of an undoped (pbi)2Ir(acac) phosphorescent layer

    NASA Astrophysics Data System (ADS)

    Lei, Xia; Yu, Junsheng; Zhao, Juan; Jiang, Yadong

    2011-11-01

    The electroluminescence (EL) characteristics of phosphorescent organic light-emitting diodes (OLEDs) with an undoped bis(1,2-dipheny1-1H-benzoimidazole) iridium (acetylacetonate) [(pbi)2Ir(acac)] emissive layer (EML) of various film thicknesses were studied. The results showed that the intensity of green light emission decreased rapidly with the increasing thickness of (pbi)2Ir(acac), which was relevant to the triplet excimer emission. It suggested that the concentration quenching of monomer emission in the undoped (pbi)2Ir(acac) film was mainly due to the formation of triplet excimer and partly due to the triplet-triplet annihilation (TTA) and triplet-polaron annihilation (TPA). A green OLED with a maximum luminance of 26,531 cd/m2, a current efficiency of 36.2 cd/A, and a power efficiency of 32.4 lm/W was obtained, when the triplet excimer emission was eliminated. Moreover, the white OLED with low efficiency roll-off was realized due to the broadened recombination zone and reduced quenching effects in the EML when no electron blocking layer was employed.

  14. Changes in cassava toxicity during processing into gari and ijapu--two fermented food products.

    PubMed

    Sokari, T G; Karibo, P S

    1992-01-01

    Grated cassava to which tap water was added at levels of 25%, 50% and 75% (v/w) was held at 30 degrees C, 40 degrees C or 50 degrees C and examined over a 6 h period for cyanide content, pH and titratable acidity (TTA). During the come-up time, i.e. the time between addition of water and attainment of desired holding temperature (between 14 and 47 min), reductions in bound cyanide of ca 54-85% occurred, depending on the level of added water and holding temperature. The corresponding losses for the control samples, to which no water was added, were ca 25-33%. The biggest reduction in the bound cyanide of > 99% (from 89.0 to 0.6 ppm) occurred in grated cassava with 75% added water held at 50 degrees C. There was little or no change in pH during the period of study. The reduction of processing time for certain cassava products based on separation into detoxication and flavour development/fermentation stages is discussed.

  15. Using spectral information in forensic imaging.

    PubMed

    Miskelly, Gordon M; Wagner, John H

    2005-12-20

    Improved detection of forensic evidence by combining narrow band photographic images taken at a range of wavelengths is dependent on the substance of interest having a significantly different spectrum from the underlying substrate. While some natural substances such as blood have distinctive spectral features which are readily distinguished from common colorants, this is not true for visualization agents commonly used in forensic science. We now show that it is possible to select reagents with narrow spectral features that lead to increased visibility using digital cameras and computer image enhancement programs even if their coloration is much less intense to the unaided eye than traditional reagents. The concept is illustrated by visualising latent fingermarks on paper with the zinc complex of Ruhemann's Purple, cyanoacrylate-fumed fingerprints with Eu(tta)(3)(phen), and soil prints with 2,6-bis(benzimidazol-2-yl)-4-[4'-(dimethylamino)phenyl]pyridine [BBIDMAPP]. In each case background correction is performed at one or two wavelengths bracketing the narrow absorption or emission band of these compounds. However, compounds with sharp spectral features would also lead to improved detection using more advanced algorithms such as principal component analysis.

  16. Utilization of tannery fleshings: Optimization of conditions for fermenting delimed tannery fleshings using Enterococcus faecium HAB01 by response surface methodology.

    PubMed

    Kumar Rai, Amit; General, Thiyam; Bhaskar, N; Suresh, P V; Sakhare, P Z; Halami, P M; Gowda, Lalitha R; Mahendrakar, N S

    2010-03-01

    Conditions for fermentation of delimed tannery fleshings--to obtain higher degree of protein hydrolysis and reasonably better antioxidant activity--using Enterococcus faecium HAB01 (GenBank #FJ418568) were optimized. Three independent variables--viz., inoculum level (X1), glucose level (X2) and fermentation time (X3)--were optimized using response surface method considering degree of hydrolysis (DH; %) and total titrable acidity (TTA) as response variables. The optimized conditions were found to be 12.5% (v/w) inoculum, 17.5% (w/w) glucose and 96h of fermentation at 37+/-1 degrees C to obtain a maximum DH%. The usefulness of the predicted model was further validated by considering random combinations of the independent factors. The chemical score of the hydrolysate revealed an excess amount of essential amino acids, viz., arginine and leucine compared to reference protein. The liquor portion had relatively high antioxidant activities, indicating its potential for use as a high value feed ingredient. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  17. Ionic liquid dependence of triplet-sensitized photon upconversion.

    PubMed

    Murakami, Yoichi; Ito, Toshiyuki; Kawai, Akio

    2014-12-11

    Photon upconversion (UC) is a technology used to convert wasted lower energy photons to usable higher energy photons. Triplet-sensitized UC based on the triplet-triplet annihilation (TTA) of organic molecules has recently received attention because of its applicability to noncoherent sunlight. Among the various media proposed for this UC, ionic liquids (ILs) are practically advantageous because of their nonvolatility and nonflammability. However, from previous studies, the efficiency of UC (ΦUC) has been found to depend on the ILs employed. In this article, systematic investigations were carried out on samples made using more than 10 kinds of ILs, all of which were purified before sample fabrication to enhance data reliability. Several clear tendencies were found, and they were all related to the viscosity of the ILs. We also found that the magnitude of their solvatochromic shifts did not correlate to these trends. These results show that the dynamic aspects of the molecules influence the kinetics that govern the magnitude of ΦUC. Along with related discussions and interpretations, these results should provide a guideline toward increasing the ΦUC.

  18. Retention-oxidation-adsorption process for emergent treatment of organic liquid spills.

    PubMed

    Liu, Xianjun; Li, Yu; Zhang, Xingwang; Lei, Lecheng

    2011-11-15

    The feasibility and effectiveness of retention-oxidation-adsorption process (ROA) for the elimination of organic contaminants induced by chemical accidents were investigated in this study. Organobentonites (DTMA-, TTA-, CTMA- and OTMA-bentonite), potassium ferrate (Fe(VI)), ozone and granular activated carbon (GAC) were used as rapid and efficient materials in the treatment and recovery of organic liquid spills. Results indicated that the retention capacities of organobentonites (especially CTMA-bentonite) were much higher than that of natural bentonite towards the chosen organic compounds. Additionally, pH, oxidant dosage, initial concentration of contaminant and chemical structure had significant influences on the effectiveness of the oxidation process. In a pilot-scale experiment, the ferrate/GAC (F/G) and ozone/GAC (O/G) processes made a comparatively good performance in the treatment of wastewater containing aniline or nitrobenzene, with the removal efficiencies of the contaminants greater than 80%. Overall, the ROA process showed a high efficiency and steady operation in the removal of hazardous organic liquids and subsequent clean up of the contaminated site. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  19. QTL mapping for fruit quality in Citrus using DArTseq markers.

    PubMed

    Curtolo, Maiara; Cristofani-Yaly, Mariângela; Gazaffi, Rodrigo; Takita, Marco Aurélio; Figueira, Antonio; Machado, Marcos Antonio

    2017-04-12

    Citrus breeding programs have many limitations associated with the species biology and physiology, requiring the incorporation of new biotechnological tools to provide new breeding possibilities. Diversity Arrays Technology (DArT) markers, combined with next-generation sequencing, have wide applicability in the construction of high-resolution genetic maps and in quantitative trait locus (QTL) mapping. This study aimed to construct an integrated genetic map using full-sib progeny derived from Murcott tangor and Pera sweet orange and DArTseq™ molecular markers and to perform QTL mapping of twelve fruit quality traits. A controlled Murcott x Pera crossing was conducted at the Citrus Germplasm Repository at the Sylvio Moreira Citrus Centre of the Agronomic Institute (IAC) located in Cordeirópolis, SP, in 1997. In 2012, 278 F 1 individuals out of a family of 312 confirmed hybrid individuals were analyzed for fruit traits and genotyped using the DArTseq markers. Using OneMap software to obtain the integrated genetic map, we considered only the DArT loci that showed no segregation deviation. The likelihood ratio and the genomic information from the available Citrus sinensis L. Osbeck genome were used to determine the linkage groups (LGs). The resulting integrated map contained 661 markers in 13 LGs, with a genomic coverage of 2,774 cM and a mean density of 0.23 markers/cM. The groups were assigned to the nine Citrus haploid chromosomes; however, some of the chromosomes were represented by two LGs due the lack of information for a single integration, as in cases where markers segregated in a 3:1 fashion. A total of 19 QTLs were identified through composite interval mapping (CIM) of the 12 analyzed fruit characteristics: fruit diameter (cm), height (cm), height/diameter ratio, weight (g), rind thickness (cm), segments per fruit, total soluble solids (TSS, %), total titratable acidity (TTA, %), juice content (%), number of seeds, TSS/TTA ratio and number of fruits per box. The genomic sequence (pseudochromosomes) of C. sinensis was compared to the genetic map, and synteny was clearly identified. Further analysis of the map regions with the highest LOD scores enabled the identification of putative genes that could be associated with the fruit quality characteristics. An integrated linkage map of Murcott tangor and Pera sweet orange using DArTseq™ molecular markers was established and it was useful to perform QTL mapping of twelve fruit quality traits. The next generation sequences data allowed the comparison between the linkage map and the genomic sequence (pseudochromosomes) of C. sinensis and the identification of genes that may be responsible for phenotypic traits in Citrus. The obtained linkage map was used to assign sequences that had not been previously assigned to a position in the reference genome.

  20. Facial trauma among victims of terrestrial transport accidents.

    PubMed

    d'Avila, Sérgio; Barbosa, Kevan Guilherme Nóbrega; Bernardino, Ítalo de Macedo; da Nóbrega, Lorena Marques; Bento, Patrícia Meira; E Ferreira, Efigênia Ferreira

    2016-01-01

    In developing countries, terrestrial transport accidents - TTA, especially those involving automobiles and motorcycles - are a major cause of facial trauma, surpassing urban violence. This cross-sectional census study attempted to determine facial trauma occurrence with terrestrial transport accidents etiology, involving cars, motorcycles, or accidents with pedestrians in the northeastern region of Brazil, and examine victims' socio-demographic characteristics. Morbidity data from forensic service reports of victims who sought care from January to December 2012 were analyzed. Altogether, 2379 reports were evaluated, of which 673 were related to terrestrial transport accidents and 103 involved facial trauma. Three previously trained and calibrated researchers collected data using a specific form. Facial trauma occurrence rate was 15.3% (n=103). The most affected age group was 20-29 years (48.3%), and more men than women were affected (2.81:1). Motorcycles were involved in the majority of accidents resulting in facial trauma (66.3%). The occurrence of facial trauma in terrestrial transport accident victims tends to affect a greater proportion of young and male subjects, and the most prevalent accidents involve motorcycles. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  1. TPH2 gene polymorphisms in the regulatory region are associated with paranoid schizophrenia in Northern Han Chinese.

    PubMed

    Xu, X M; Ding, M; Pang, H; Wang, B J

    2014-03-12

    In the last years, serotonin (5-HT) has been related with the pathophysiology of several psychiatric disorders, including schizophrenia. Thus, genes related to the serotonergic (5-HTergic) system are good candidate genes for schizophrenia. The rate-limiting enzyme of 5-HT synthesis is tryptophan hydroxylase 2 (TPH2). Single nucleotide polymorphisms (SNPs) in the regulatory regions of TPH2 gene may affect gene expression and biosynthesis of 5-HT triggering to various neuropsychiatric disorders related to 5-HT dysfunction. The present study explored the association of SNPs within the TPH2 gene with paranoid schizophrenia in Han Chinese. A total of 164 patients with schizophrenia and 244 healthy controls were genotyped for six TPH2 SNPs (rs4570625, rs11178997, rs11178998, rs41317118, rs17110747, and rs41317114). Significant group differences were observed in the allele and genotype frequencies of rs4570625 and in the frequencies of GTA and TTA haplotypes corresponding to rs4570625-rs11178997-rs11178998. Our findings suggest that common genetic variations of TPH2 are likely to contribute to genetic susceptibility to paranoid schizophrenia in Han Chinese. Further studies in larger samples are needed to replicate this association.

  2. Chiroptical methods in a wide wavelength range for obtaining Ln3+ complexes with circularly polarized luminescence of practical interest.

    PubMed

    Górecki, Marcin; Carpita, Luca; Arrico, Lorenzo; Zinna, Francesco; Di Bari, Lorenzo

    2018-05-29

    We studied enantiopure chiral trivalent lanthanide (Ln3+ = La3+, Sm3+, Eu3+, Gd3+, Tm3+, and Yb3+) complexes with two fluorinated achiral tris(β-diketonate) ligands (HFA = hexafluoroacetylacetonate and TTA = 2-thenoyltrifluoroacetonate), incorporating a chiral bis(oxazolinyl)pyridine (PyBox) unit as a neutral ancillary ligand, by the combined use of optical and chiroptical methods, ranging from UV to IR both in absorption and circular dichroism (CD), and including circularly polarized luminescence (CPL). Ultimately, all the spectroscopic information is integrated into a total and a chiroptical super-spectrum, which allows one to characterize a multidimensional chemical space, spanned by the different Ln3+ ions, the acidity and steric demand of the diketone and the chirality of the PyBox ligand. In all cases, the Ln3+ ions endow the systems with peculiar chiroptical properties, either allied to f-f transitions or induced by the metal onto the ligand. In more detail, we found that Sm3+ complexes display interesting CPL features, which partly superimpose and partly integrate the more common Eu3+ properties. Especially, in the context of security tags, the pair Sm/Eu may be a winning choice for chiroptical barcoding.

  3. Lent-On-Plus Lentiviral vectors for conditional expression in human stem cells.

    PubMed

    Benabdellah, Karim; Muñoz, Pilar; Cobo, Marién; Gutierrez-Guerrero, Alejandra; Sánchez-Hernández, Sabina; Garcia-Perez, Angélica; Anderson, Per; Carrillo-Gálvez, Ana Belén; Toscano, Miguel G; Martin, Francisco

    2016-11-17

    Conditional transgene expression in human stem cells has been difficult to achieve due to the low efficiency of existing delivery methods, the strong silencing of the transgenes and the toxicity of the regulators. Most of the existing technologies are based on stem cells clones expressing appropriate levels of tTA or rtTA transactivators (based on the TetR-VP16 chimeras). In the present study, we aim the generation of Tet-On all-in-one lentiviral vectors (LVs) that tightly regulate transgene expression in human stem cells using the original TetR repressor. By using appropriate promoter combinations and shielding the LVs with the Is2 insulator, we have constructed the Lent-On-Plus Tet-On system that achieved efficient transgene regulation in human multipotent and pluripotent stem cells. The generation of inducible stem cell lines with the Lent-ON-Plus LVs did not require selection or cloning, and transgene regulation was maintained after long-term cultured and upon differentiation toward different lineages. To our knowledge, Lent-On-Plus is the first all-in-one vector system that tightly regulates transgene expression in bulk populations of human pluripotent stem cells and its progeny.

  4. Lent-On-Plus Lentiviral vectors for conditional expression in human stem cells

    PubMed Central

    Benabdellah, Karim; Muñoz, Pilar; Cobo, Marién; Gutierrez-Guerrero, Alejandra; Sánchez-Hernández, Sabina; Garcia-Perez, Angélica; Anderson, Per; Carrillo-Gálvez, Ana Belén; Toscano, Miguel G.; Martin, Francisco

    2016-01-01

    Conditional transgene expression in human stem cells has been difficult to achieve due to the low efficiency of existing delivery methods, the strong silencing of the transgenes and the toxicity of the regulators. Most of the existing technologies are based on stem cells clones expressing appropriate levels of tTA or rtTA transactivators (based on the TetR-VP16 chimeras). In the present study, we aim the generation of Tet-On all-in-one lentiviral vectors (LVs) that tightly regulate transgene expression in human stem cells using the original TetR repressor. By using appropriate promoter combinations and shielding the LVs with the Is2 insulator, we have constructed the Lent-On-Plus Tet-On system that achieved efficient transgene regulation in human multipotent and pluripotent stem cells. The generation of inducible stem cell lines with the Lent-ON-Plus LVs did not require selection or cloning, and transgene regulation was maintained after long-term cultured and upon differentiation toward different lineages. To our knowledge, Lent-On-Plus is the first all-in-one vector system that tightly regulates transgene expression in bulk populations of human pluripotent stem cells and its progeny. PMID:27853296

  5. An Efficient and Versatile System for Visualization and Genetic Modification of Dopaminergic Neurons in Transgenic Mice

    PubMed Central

    Kramer, Edgar R.

    2015-01-01

    Background & Aims The brain dopaminergic (DA) system is involved in fine tuning many behaviors and several human diseases are associated with pathological alterations of the DA system such as Parkinson’s disease (PD) and drug addiction. Because of its complex network integration, detailed analyses of physiological and pathophysiological conditions are only possible in a whole organism with a sophisticated tool box for visualization and functional modification. Methods & Results Here, we have generated transgenic mice expressing the tetracycline-regulated transactivator (tTA) or the reverse tetracycline-regulated transactivator (rtTA) under control of the tyrosine hydroxylase (TH) promoter, TH-tTA (tet-OFF) and TH-rtTA (tet-ON) mice, to visualize and genetically modify DA neurons. We show their tight regulation and efficient use to overexpress proteins under the control of tet-responsive elements or to delete genes of interest with tet-responsive Cre. In combination with mice encoding tet-responsive luciferase, we visualized the DA system in living mice progressively over time. Conclusion These experiments establish TH-tTA and TH-rtTA mice as a powerful tool to generate and monitor mouse models for DA system diseases. PMID:26291828

  6. Photofunctional hybrids of lanthanide functionalized bio-MOF-1 for fluorescence tuning and sensing.

    PubMed

    Shen, Xiang; Yan, Bing

    2015-08-01

    A series of luminescent Ln(3+)@bio-MOF-1 (Ln=Eu, Tb, bio-MOF-1=Zn8(ad)4(BPDC)6O⋅2Me2NH2 (ad=adeninate, BPDC=biphenyldicarboxylate)) are synthesized via postsynthetic cation exchange by encapsulating lanthanide ions into an anionic metal-organic framework (MOF), and their photophysical properties are studied. After loading 2-thenoyltrifluroacetone (TTA) as sensitized ligand by a gas diffusion ("ship-in-bottle") method, it is found that the luminescent intensity of Eu(3+) is enhanced. Especially, when loading two different lanthanide cations into bio-MOF-1, the luminescent color can be tuned to close white (light pink) light output. Additionally, bio-MOF-1 and Eu(3+)@bio-MOF-1 are selected as representative samples for sensing metal ions. When bio-MOF-1 is immersed in the aqueous solutions of different metal ions, it shows highly sensitive sensing for Fe(3+) as well as Eu(3+)@bio-MOF-1 immersed in the DMF solutions of different metal ion. The results are benefit for the further application of functionalized bio-MOFs in practical fields. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Spatial exciton allocation strategy with reduced energy loss for high-efficiency fluorescent/phosphorescent hybrid white organic light-emitting diodes

    DOE PAGES

    Zhao, Fangchao; Wei, Ying; Xu, Hui; ...

    2017-05-17

    Due to the poor operational lifetime of blue phosphorescent dopants and blue thermally activated delayed fluorescent (TADF) materials, hybrid white organic light-emitting diodes (WOLEDs) with conventional blue fluorescent emitters are still preferred for commercial applications in general lighting. However, the improvement in the overall efficiency of hybrid WOLEDs has been limited due to energy losses during the energy transfer process and exciton quenching after the spatial separation of the singlet and triplet excitons. Here we demonstrate the development of a Spatial Exciton Allocation Strategy (SEAS) to achieve close to 100% internal quantum efficiency (IQE) in blue-yellow complementary color hybrid WOLEDs.more » The employed blue fluorophore not only has a resonant triplet level with the yellow phosphor to reduce energy loss during energy transfer processes and triplet–triplet annihilation (TTA), but also has a resonant singlet level with the electron transport layer to extend singlet exciton distribution and enhance both singlet and triplet exciton utilization. Thus, the resulting hybrid WOLEDs exhibited 104 lm W -1 efficacy at 100 cd m -2 and 74 lm W -1 at 1000 cd m -2 with CIE coordinates of (0.42, 0.44) which is warm white and suitable for indoor lighting.« less

  8. Technical advance: stringent control of transgene expression in Arabidopsis thaliana using the Top10 promoter system

    NASA Technical Reports Server (NTRS)

    Love, J.; Scott, A. C.; Thompson, W. F.; Brown, C. S. (Principal Investigator)

    2000-01-01

    We show that the tightly regulated tetracycline-sensitive Top10 promoter system (Weinmann et al. Plant J. 1994, 5, 559-569) is functional in Arabidopsis thaliana. A pure breeding A. thaliana line (JL-tTA/8) was generated which expressed a chimeric fusion of the tetracycline repressor and the activation domain of Herpes simplex virus (tTA), from a single transgenic locus. Plants from this line were crossed with transgenics carrying the ER-targeted green fluorescent protein coding sequence (mGFP5) under control of the Top10 promoter sequence. Progeny from this cross displayed ER-targeted GFP fluorescence throughout the plant, indicating that the tTA-Top10 promoter interaction was functional in A. thaliana. GFP expression was repressed by 100 ng ml-1 tetracycline, an order of magnitude lower than the concentration used previously to repress expression in Nicotiana tabacum. Moreover, the level of GFP expression was controlled by varying the concentration of tetracycline in the medium, allowing a titred regulation of transgenic activity that was previously unavailable in A. thaliana. The kinetics of GFP activity were determined following de-repression of the Top10:mGFP5 transgene, with a visible ER-targeted GFP signal appearing from 24 to 48 h after de-repression.

  9. Gateway Vectors for Efficient Artificial Gene Assembly In Vitro and Expression in Yeast Saccharomyces cerevisiae

    PubMed Central

    Giuraniuc, Claudiu V.; MacPherson, Murray; Saka, Yasushi

    2013-01-01

    Construction of synthetic genetic networks requires the assembly of DNA fragments encoding functional biological parts in a defined order. Yet this may become a time-consuming procedure. To address this technical bottleneck, we have created a series of Gateway shuttle vectors and an integration vector, which facilitate the assembly of artificial genes and their expression in the budding yeast Saccharomyces cerevisiae. Our method enables the rapid construction of an artificial gene from a promoter and an open reading frame (ORF) cassette by one-step recombination reaction in vitro. Furthermore, the plasmid thus created can readily be introduced into yeast cells to test the assembled gene’s functionality. As flexible regulatory components of a synthetic genetic network, we also created new versions of the tetracycline-regulated transactivators tTA and rtTA by fusing them to the auxin-inducible degron (AID). Using our gene assembly approach, we made yeast expression vectors of these engineered transactivators, AIDtTA and AIDrtTA and then tested their functions in yeast. We showed that these factors can be regulated by doxycycline and degraded rapidly after addition of auxin to the medium. Taken together, the method for combinatorial gene assembly described here is versatile and would be a valuable tool for yeast synthetic biology. PMID:23675537

  10. Spatial exciton allocation strategy with reduced energy loss for high-efficiency fluorescent/phosphorescent hybrid white organic light-emitting diodes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao, Fangchao; Wei, Ying; Xu, Hui

    Due to the poor operational lifetime of blue phosphorescent dopants and blue thermally activated delayed fluorescent (TADF) materials, hybrid white organic light-emitting diodes (WOLEDs) with conventional blue fluorescent emitters are still preferred for commercial applications in general lighting. However, the improvement in the overall efficiency of hybrid WOLEDs has been limited due to energy losses during the energy transfer process and exciton quenching after the spatial separation of the singlet and triplet excitons. Here we demonstrate the development of a Spatial Exciton Allocation Strategy (SEAS) to achieve close to 100% internal quantum efficiency (IQE) in blue-yellow complementary color hybrid WOLEDs.more » The employed blue fluorophore not only has a resonant triplet level with the yellow phosphor to reduce energy loss during energy transfer processes and triplet–triplet annihilation (TTA), but also has a resonant singlet level with the electron transport layer to extend singlet exciton distribution and enhance both singlet and triplet exciton utilization. Thus, the resulting hybrid WOLEDs exhibited 104 lm W -1 efficacy at 100 cd m -2 and 74 lm W -1 at 1000 cd m -2 with CIE coordinates of (0.42, 0.44) which is warm white and suitable for indoor lighting.« less

  11. G-Quadruplex conformational change driven by pH variation with potential application as a nanoswitch.

    PubMed

    Yan, Yi-Yong; Tan, Jia-Heng; Lu, Yu-Jing; Yan, Siu-Cheong; Wong, Kwok-Yin; Li, Ding; Gu, Lian-Quan; Huang, Zhi-Shu

    2013-10-01

    G-Quadruplex is a highly polymorphic structure, and its behavior in acidic condition has not been well studied. Circular dichroism (CD) spectra were used to study the conformational change of G-quadruplex. The thermal stabilities of the G-quadruplex were measured with CD melting. Interconversion kinetics profiles were investigated by using CD kinetics. The fluorescence of the inserted 2-Aminopurine (Ap) was monitored during pH change and acrylamide quenching, indicating the status of the loop. Proton NMR was adopted to help illustrate the change of the conformation. G-Quadruplex of specific loop was found to be able to transform upon pH variation. The transformation was resulted from the loop rearrangement. After screening of a library of diverse G-quadruplex, a sequence exhibiting the best transformation property was found. A pH-driven nanoswitch with three gears was obtained based on this transition cycle. Certain G-quadruplex was found to go through conformational change at low pH. Loop was the decisive factor controlling the interconversion upon pH variation. G-Quadruplex with TT central loop could be converted in a much milder condition than the one with TTA loop. It can be used to design pH-driven nanodevices such as a nanoswitch. These results provide more insights into G-quadruplex polymorphism, and also contribute to the design of DNA-based nanomachines and logic gates. © 2013.

  12. Dual emission behavior of phenyleneethynylene gold(I) complexes dictated by intersystem crossing: a theoretical perspective.

    PubMed

    Wang, Li; Li, Yuanyuan; Zhang, Yanxin; He, Hongqing; Zhang, Jinglai

    2015-02-25

    In commonly studied gold(I) complexes with oligo (o-, p-, or m-phenyleneethynylene) (PE) ligands, an intriguing photophysical behavior is dual emission composed of fluorescence from S1 and phosphorescence from T1 which is dictated by effective intersystem crossing (ISC) process. In order to explore the salient photodynamics of such oligo-PE gold(I) complexes effectively, we have deliberately chosen three model complexes, namely, Ph-C≡C-Au(PMe3) (1a') and Ph-C≡C-(1,m)C6H4-C≡C-Au(PMe3) (m=4, 2a'; m=3, 3a') in place of the real system. Firstly, electronic structure methods based on DFT and TD-DFT are utilized to perform optimization calculations for the ground- and lowest-lying excited states, respectively. Next, basic photophysical properties including absorption and emission spectra are investigated by TD-DFT under the optimized geometries. Besides, on the basis of the electronic spectra herein, we succeed in searching for surface intersections as the minima on the seam of singlet-triplet surface crossings (SCs) at the CASSCF level of theory. By integration of the results available, the process of delayed fluorescence of triplet-triplet annihilation (TTA) and phosphorescence was displayed in detail with SCs playing the lead in monitoring the ISC. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Role of adipocyte lipid-binding protein (ALBP) and acyl-coA binding protein (ACBP) in PPAR-mediated transactivation.

    PubMed

    Helledie, Torben; Jørgensen, Claus; Antonius, Marianne; Krogsdam, Ann M; Kratchmarova, Irina; Kristiansen, Karsten; Mandrup, Susanne

    2002-10-01

    Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors that are activated by a number of fatty acids and fatty acid derivatives. By contrast, we have recently shown that acyl-CoA esters display PPAR antagonistic properties in vitro. We have also shown that the adipocyte lipid binding protein (ALBP), the keratinocyte lipid binding protein (KLBP) and the acyl-CoA binding protein (ACBP) exhibit a prominent nuclear localization in differentiating 3T3-L1 adipocytes. Similarly, ectopic expression of these proteins in CV-1 cells resulted in a primarily nuclear localization. We therefore speculated that FABPs and ACBP might regulate the availability of PPAR agonists and antagonists by affecting not only their esterification in the cytoplasm but also their transport to and availability in the nucleus. We show here that coexpression of ALBP or ACBP exerts a negative effect on ligand-dependent PPAR transactivation, when tetradecylthioacetic (TTA) is used as ligand but not when the thiazolidinedione BRL49653 is used as ligand. The results presented here do not support the hypothesis that ALBP facilitates the transport of the fatty acid-type ligands to the nucleus, rather ALBP appears to sequester or increase the turn-over of the agonist. Similarly, our results are in keeping with a model in which ACBP increase the metabolism of these ligands.

  14. Novel Electrospun Dual-Layered Composite Nanofibrous Membrane Endowed with Electricity-Magnetism Bifunctionality at One Layer and Photoluminescence at the Other Layer.

    PubMed

    Wang, Zijiao; Ma, Qianli; Dong, Xiangting; Li, Dan; Xi, Xue; Yu, Wensheng; Wang, Jinxian; Liu, Guixia

    2016-10-05

    Dual-layered composite nanofibrous membrane equipped with electrical conduction, magnetism and photoluminescence trifunctionality is constructed via electrospinning. The composite membrane consists of a polyaniline (PANI)/Fe 3 O 4 nanoparticles (NPs)/polyacrylonitrile (PAN) tuned electrical-magnetic bifunctional nanofibrous layer at one side and a Eu(TTA) 3 (TPPO) 2 /polyvinylpyrrolidone (PVP) photoluminescent nanofibrous layer at the other side, and the two layers are tightly combined face-to-face together into the novel dual-layered composite membrane with trifunctionality. The electric conductivity and magnetism of electrical-magnetic bifunctionality can be respectively tunable via modulating the respective PANI and Fe 3 O 4 NPs contents, and the highest electric conductivity approaches the order of 1 × 10 -2 S cm -1 . Predominant red emission at 615 nm can be obviously observed in the photoluminescent layer under 366 nm excitation. Moreover, the luminescent intensity of photoluminescent layer is almost unaffected by the electrical-magnetic bifunctional layer because of the fact that the photoluminescent materials have been successfully isolated from dark-colored PANI and Fe 3 O 4 NPs. The novel dual-layered composite nanofibrous membrane with trifunctionality has potentials in many fields. Furthermore, the design philosophy and fabrication method for the dual-layered multifunctional membrane provide a new and facile strategy toward other membranes with multifunctionality.

  15. Complete mitochondrial genomes of three crickets (Orthoptera: Gryllidae) and comparative analyses within Ensifera mitogenomes.

    PubMed

    Yang, Jing; Ren, Qianli; Huang, Yuan

    2016-03-17

    The complete mitochondrial genomes (mitogenomes) of Velarifictorus hemelytrus, Loxoblemmus equestris and Teleogryllus emma are 16123 bp, 16314 bp and 15697 bp, in size, respectively. All three mitogenomes possess the same gene order of the inversion of the gene cluster trnE-trnS(AGN)-trnN compared with the ancestral gene order of Orthoptera. The atypical initiation codon for the cox1 gene in three crickets is TTA. Pronounced A skew and T skew have been found in Grylloidea comparing with Gryllotalpoidea and Tettigonioidea. The T-stretch in the minority strand is interrupted by C to form (T)n(C)2(T)n sequences in five species of Gryllinae (V. hemelytrus, L. equestris, T. emma, T. oceanicus, T. commodus). This T-stretch variant with its neighbouring A-stretch variant (A-stretch is interrupted by G), which were discovered in the A+T-rich regions of all taxa from infraorder Gryllidea, could form a conserved stem-loop structure (including 15 ~ 17 base pairs). This potential stem-loop structure is a favorable candidate that may participate in the replication origin of the minority strand of Gryllidea mitogenome. Phylogenetic analysis indicated that within the Gryllinae, genus Teleogryllus and Velarifictorus are closely related, sister to the genus Loxoblemmus. The relationships among the five superfamilies of Ensifera presented here were ((Grylloidea, Gryllotalpoidea) (Tettigonioidea, (Hagloidea, Rhaphidophoroidea))).

  16. The Fitness Advantage of Commercial Wine Yeasts in Relation to the Nitrogen Concentration, Temperature, and Ethanol Content under Microvinification Conditions

    PubMed Central

    García-Ríos, Estéfani; Gutiérrez, Alicia; Salvadó, Zoel; Arroyo-López, Francisco Noé

    2014-01-01

    The effect of the main environmental factors governing wine fermentation on the fitness of industrial yeast strains has barely received attention. In this study, we used the concept of fitness advantage to measure how increasing nitrogen concentrations (0 to 200 mg N/liter), ethanol (0 to 20%), and temperature (4 to 45°C) affects competition among four commercial wine yeast strains (PDM, ARM, RVA, and TTA). We used a mathematical approach to model the hypothetical time needed for the control strain (PDM) to out-compete the other three strains in a theoretical mixed population. The theoretical values obtained were subsequently verified by competitive mixed fermentations in both synthetic and natural musts, which showed a good fit between the theoretical and experimental data. Specifically, the data show that the increase in nitrogen concentration and temperature values improved the fitness advantage of the PDM strain, whereas the presence of ethanol significantly reduced its competitiveness. However, the RVA strain proved to be the most competitive yeast for the three enological parameters assayed. The study of the fitness of these industrial strains is of paramount interest for the wine industry, which uses them as starters of their fermentations. Here, we propose a very simple method to model the fitness advantage, which allows the prediction of the competitiveness of one strain with respect to different abiotic factors. PMID:24242239

  17. Industrial enzymatic production of cephalosporin-based beta-lactams.

    PubMed

    Barber, Michael S; Giesecke, Ulrich; Reichert, Arno; Minas, Wolfgang

    2004-01-01

    Cephalosporins are chemically closely related to penicillins both work by inhibiting the cell wall synthesis of bacteria. The first generation cephalosporins entered the market in 1964. Second and third generation cephalosporins were subsequently developed that were more powerful than the original products. Fourth generation cephalosporins are now reaching the market. Each newer generation of cephalosporins has greater Gram-negative antimicrobial properties than the preceding generation. Conversely, the 'older' generations of cephalosporins have greater Gram-positive (Staphylococcus and Streptococcus) coverage than the 'newer' generations. Frequency of dosing decreases and palatability generally improve with increasing generations. The advent of fourth generation cephalosporins with the launch of cefepime extended the spectrum against Gram-positive organisms without a significant loss of activity towards Gram-negative bacteria. Its greater stability to beta-lactamases increases its efficacy against drug-resistant bacteria. In this review we present the current situation of this mature market. In addition, we present the current state of the technologies employed for the production of cephalosporins, focusing on the new and environmentally safer 'green' routes to the products. Starting with the fermentation and purification of CPC, enzymatic conversion in conjunction with aqueous chemistry will lead to some key intermediates such as 7-ACA, TDA and TTA, which then can be converted into the active pharmaceutical ingredient (API), again applying biocatalytic technologies and aqueous chemistry. Examples for the costing of selected products are provided as well.

  18. Optimization of alkaline sulfite pretreatment and comparative study with sodium hydroxide pretreatment for improving enzymatic digestibility of corn stover.

    PubMed

    Liu, Huan; Pang, Bo; Wang, Haisong; Li, Haiming; Lu, Jie; Niu, Meihong

    2015-04-01

    In this study, alkaline sulfite pretreatment of corn stover was optimized. The influences of pretreatments on solid yield, delignification, and carbohydrate recovery under different pretreatment conditions and subsequent enzymatic hydrolysis were investigated. The effect of pretreatment was evaluated by enzymatic hydrolysis efficiency and the total sugar yield. The optimum pretreatment conditions were obtained, as follows: the total titratable alkali (TTA) of 12%, liquid/solid ratio of 6:1, temperature of 140 °C, and holding time of 20 min. Under those conditions, the solid yield was 55.24%, and the removal of lignin was 82.68%. Enzymatic hydrolysis rates of glucan and xylan for pretreated corn stover were 85.38% and 70.36%, and the total sugar yield was 74.73% at cellulase loading of 20 FPU/g and β-glucosidase loading of 10 IU/g for 48 h. Compared with sodium hydroxide pretreatment with the same amount of total titratable alkali, the total sugar yield was raised by about 10.43%. Additionally, the corn stover pretreated under the optimum pretreatment conditions was beaten by PFI at 1500 revolutions. After beating, enzymatic hydrolysis rates of glucan and xylan were 89.74% and 74.06%, and the total sugar yield was 78.58% at the same enzymatic hydrolysis conditions. Compared with 1500 rpm of PFI beating after sodium pretreatment with the same amount of total titratable alkali, the total sugar yield was raised by about 14.05%.

  19. The effect of packaging methods (paper, active paper, and edible coating) on the characteristic of papaya MJ9 in ambient temperature storage

    NASA Astrophysics Data System (ADS)

    Suwanti, D.; Utami, R.; Kawiji; Praseptiangga, D.; Khasanah, L. U.

    2018-01-01

    Papaya is one of the export commodities that contain high vitamin C but having short shelf-life. One method that use to extend the shelf-life and maintain the quality of papaya is packaging. The aim of this study was to investigate the effect of the packaging methods (paper, active paper and edible coating) on the characteristics of papaya MJ9 (weight loss, firmness, total soluble solid (TSS), Total Titratable Acid (TTA), pH, vitamin C and total mold and yeast). The packaging methods were control (F1), wrapping paper (F2), wrapping active paper (F3), combination of edible coating and wrapping paper (F4), and combination of edible coating and wrapping active paper (F5). The result showed that paper packaging, edible coating and active paper packaging significantly affected the weight loss, firmness, total soluble solid, total titratable acids, pH, vitamin C, and total mold and yeast of papaya. The weight loss, total soluble solid and pH of packaged papaya was lower than that of control sample, however, the value of firmness and total titratable acid was higher than that of the control sample. Packaging can inhibit the increase of weight loss, total soluble solids and pH, and the decrease of firmness, total titratable acid, vitamin C and total mold and yeast. Based on the papaya characteristics, the selected packaging method was the combination of edible coating and wrapping active paper.

  20. Animal Rennets as Sources of Dairy Lactic Acid Bacteria

    PubMed Central

    Cruciata, Margherita; Sannino, Ciro; Ercolini, Danilo; Scatassa, Maria L.; De Filippis, Francesca; Mancuso, Isabella; La Storia, Antonietta; Moschetti, Giancarlo

    2014-01-01

    The microbial composition of artisan and industrial animal rennet pastes was studied by using both culture-dependent and -independent approaches. Pyrosequencing targeting the 16S rRNA gene allowed to identify 361 operational taxonomic units (OTUs) to the genus/species level. Among lactic acid bacteria (LAB), Streptococcus thermophilus and some lactobacilli, mainly Lactobacillus crispatus and Lactobacillus reuteri, were the most abundant species, with differences among the samples. Twelve groups of microorganisms were targeted by viable plate counts revealing a dominance of mesophilic cocci. All rennets were able to acidify ultrahigh-temperature-processed (UHT) milk as shown by pH and total titratable acidity (TTA). Presumptive LAB isolated at the highest dilutions of acidified milks were phenotypically characterized, grouped, differentiated at the strain level by randomly amplified polymorphic DNA (RAPD)-PCR analysis, and subjected to 16S rRNA gene sequencing. Only 18 strains were clearly identified at the species level, as Enterococcus casseliflavus, Enterococcus faecium, Enterococcus faecalis, Enterococcus lactis, Lactobacillus delbrueckii, and Streptococcus thermophilus, while the other strains, all belonging to the genus Enterococcus, could not be allotted into any previously described species. The phylogenetic analysis showed that these strains might represent different unknown species. All strains were evaluated for their dairy technological performances. All isolates produced diacetyl, and 10 of them produced a rapid pH drop in milk, but only 3 isolates were also autolytic. This work showed that animal rennet pastes can be sources of LAB, mainly enterococci, that might contribute to the microbial diversity associated with dairy productions. PMID:24441167

  1. Electron-Deficient Near-Infrared Pt(II) and Pd(II) Benzoporphyrins with Dual Phosphorescence and Unusually Efficient Thermally Activated Delayed Fluorescence: First Demonstration of Simultaneous Oxygen and Temperature Sensing with a Single Emitter.

    PubMed

    Zach, Peter W; Freunberger, Stefan A; Klimant, Ingo; Borisov, Sergey M

    2017-11-01

    We report a family of Pt and Pd benzoporphyrin dyes with versatile photophysical properties and easy access from cheap and abundant chemicals. Attaching 4 or 8 alkylsulfone groups onto a meso-tetraphenyltetrabenzoporphyrin (TPTBP) macrocylcle renders the dyes highly soluble in organic solvents, photostable, and electron-deficient with the redox potential raised up to 0.65 V versus the parent porphyrin. The new dyes intensively absorb in the blue (Soret band, 440-480 nm) and in the red (Q-band, 620-650 nm) parts of the electromagnetic spectrum and show bright phosphorescence at room-temperature in the NIR with quantum yields up to 30% in solution. The small singlet-triplet energy gap yields unusually efficient thermally activated delayed fluorescence (TADF) at elevated temperatures in solution and in polymeric matrices with quantum yields as high as 27% at 120 °C, which is remarkable for benzoporphyrins. Apart from oxygen sensing, these properties enable unprecedented simultaneous, self-referenced oxygen and temperature sensing with a single indicator dye: whereas oxygen can be determined either via the decay time of phosphorescence or TADF, the temperature is accessed via the ratio of the two emissions. Moreover, the dyes are efficient sensitizers for triplet-triplet annihilation (TTA)-based upconversion making possible longer sensitization wavelength than the conventional benzoporphyrin complexes. The Pt-octa-sulfone dye also features interesting semireversible transformation in basic media, which generates new NIR absorbing species.

  2. Quantitative photogrammetric analysis of the Klapp method for treating idiopathic scoliosis.

    PubMed

    Iunes, Denise H; Cecílio, Maria B B; Dozza, Marina A; Almeida, Polyanna R

    2010-01-01

    Few studies have proved that physical therapy techniques are efficient in the treatment of scoliosis. To analyze the efficiency of the Klapp method for the treatment of scoliosis, through a quantitative analysis using computerized biophotogrammetry. Sixteen participants of a mean age of 15+/-2.61 yrs. with idiopathic scoliosis were treated using the Klapp method. To analyze the results from the treatment, they were all of photographed before and after the treatments, following a standardized photographic method. All of the photographs were analyzed quantitatively by the same examiner using the ALCimagem 2000 software. The statistical analyses were performed using the paired t-test with a significance level of 5%. The treatments showed improvements in the angles which evaluated the symmetry of the shoulders, i.e. the acromioclavicular joint angle (AJ; p=0.00) and sternoclavicular joint angle (SJ; p=0.01). There were also improvements in the angle that evaluated the left Thales triangle (DeltaT; p=0.02). Regarding flexibility, there were improvements in the tibiotarsal angle (TTA; p=0.01) and in the hip joint angles (HJA; p=0.00). There were no changes in the vertebral curvatures and nor improvements in head positioning. Only the lumbar curvature, evaluated by the lumbar lordosis angle (LL; p=0.00), changed after the treatments. The Klapp method was an efficient therapeutic technique for treating asymmetries of the trunk and improving its flexibility. However, it was not efficient for pelvic asymmetry modifications in head positioning, cervical lordosis or thoracic kyphosis.

  3. Reduction of acrylamide in whole-wheat bread by combining lactobacilli and yeast fermentation.

    PubMed

    Nasiri Esfahani, Behnaz; Kadivar, Mahdi; Shahedi, Mohammad; Soleimanian-Zad, Sabihe

    2017-11-01

    This study mainly focuses on a strategy for reducing acrylamide content in whole-wheat bread by combining lactobacilli and yeast in sourdough breadmaking. Combinations of sourdough (fermented dough using different Lactobacillus strains including Lactobacillus plantarum PTCC 1896 [probiotic], L. sakei DSM 20,017, L. rhamnosus DSM 20,021, and L. delbrueckii DSM 20,081) and yeast, in comparison with yeast alone, were used for breadmaking. The results showed that acrylamide levels in breads fermented using sourdough+yeast were in all cases much lower (6.9-20 μg/kg on a dry weight basis [d.b.]) than those in the yeast-only fermented bread (47.6 μg/kg d.b.). Significant (p < 0.05) correlations were also found between pH, total titratable acids (TTA) and lactic acid, and acrylamide content. Furthermore, the obtained results showed that the moisture content of dough directly influenced the formation of acrylamide in bread (r = 0.925, p < 0.0001). In addition, no significant correlations were observed between acrylamide content in breads and either the reducing sugar or free amino acid contents in dough samples. According to the different effects of Lactobacillus strains, it could be concluded that the acrylamide reducing potential of lactobacilli was strain-specific, with L. rhamnosus being the most effective. This suggests that sourdough fermentation with appropriate Lactobacillus strains can be used as an advantageous technology to reduce the acrylamide content of whole-wheat breads.

  4. Sex-specific effect of Pirin gene on bone mineral density in a cohort of 4000 Chinese.

    PubMed

    Tang, Nelson L S; Liao, Chen Di; Ching, Jasmine K L; Suen, Eddie W C; Chan, Iris H S; Orwoll, Eric; Ho, Suzanne C; Chan, Frank W K; Kwok, Anthony W L; Kwok, Timothy; Woo, Jean; Leung, Ping Chung

    2010-02-01

    Osteoporosis is a common condition among elderly. Genetic mapping studies repeatedly located the distal short arms of X-chromosome as the quantitative trait loci (QTL) for BMD in mice. Fine mapping of a syntenic segment on Xp22 in a Caucasian female population suggested a moderate association between lumbar spine (LS) BMD and 2 intronic SNPs in the Pirin (PIR) gene, which encodes an iron-binding nuclear protein. This study aimed to examine genetic variations in the PIR gene by a comprehensive tagging method and its sex-specific effects on BMD and osteoporotic risk. Two thousand men and 2000 women aged 65 or above were recruited from the community. BMDs at the LS, femoral neck, total hip and whole body were measured and followed up at 4-year. Genotyping was performed for tagSNPs of PIR gene including adjacent regions, and the PIR haplotypes were inferred using PHASE program. Analysis by linear regression showed a significant association between SNP rs5935970 and LS-BMD, while haplotype T-T-A was significantly associated with BMD of all measured sites. However, none of such associations were found in men. Linear Mixed Model also confirmed the same sex-specific and site-specific effect for longitudinal BMD changes. In addition to confirming the association between BMDs and the PIR gene, we also revealed that this finding is sex-specific, possibly due to an X-linked effect. This study demonstrated the importance of considering sex and genetic interactions in studies of disease predisposition and complex traits. (c) 2009 Elsevier Inc. All rights reserved.

  5. Kinetic Monte Carlo simulation of the efficiency roll-off, emission color, and degradation of organic light-emitting diodes (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Coehoorn, Reinder; van Eersel, Harm; Bobbert, Peter A.; Janssen, Rene A. J.

    2015-10-01

    The performance of Organic Light Emitting Diodes (OLEDs) is determined by a complex interplay of the charge transport and excitonic processes in the active layer stack. We have developed a three-dimensional kinetic Monte Carlo (kMC) OLED simulation method which includes all these processes in an integral manner. The method employs a physically transparent mechanistic approach, and is based on measurable parameters. All processes can be followed with molecular-scale spatial resolution and with sub-nanosecond time resolution, for any layer structure and any mixture of materials. In the talk, applications to the efficiency roll-off, emission color and lifetime of white and monochrome phosphorescent OLEDs [1,2] are demonstrated, and a comparison with experimental results is given. The simulations show to which extent the triplet-polaron quenching (TPQ) and triplet-triplet-annihilation (TTA) contribute to the roll-off, and how the microscopic parameters describing these processes can be deduced properly from dedicated experiments. Degradation is treated as a result of the (accelerated) conversion of emitter molecules to non-emissive sites upon a triplet-polaron quenching (TPQ) process. The degradation rate, and hence the device lifetime, is shown to depend on the emitter concentration and on the precise type of TPQ process. Results for both single-doped and co-doped OLEDs are presented, revealing that the kMC simulations enable efficient simulation-assisted layer stack development. [1] H. van Eersel et al., Appl. Phys. Lett. 105, 143303 (2014). [2] R. Coehoorn et al., Adv. Funct. Mater. (2015), publ. online (DOI: 10.1002/adfm.201402532)

  6. Hepatocyte-Specific Expression of Human Lysosome Acid Lipase Corrects Liver Inflammation and Tumor Metastasis in lal−/− Mice

    PubMed Central

    Du, Hong; Zhao, Ting; Ding, Xinchun; Yan, Cong

    2016-01-01

    The liver is a major organ for lipid synthesis and metabolism. Deficiency of lysosomal acid lipase (LAL; official name Lipa, encoded by Lipa) in mice (lal−/−) results in enlarged liver size due to neutral lipid storage in hepatocytes and Kupffer cells. To test the functional role of LAL in hepatocyte, hepatocyte-specific expression of human LAL (hLAL) in lal−/− mice was established by cross-breeding of liver-activated promoter (LAP)–driven tTA transgene and (tetO)7-CMV-hLAL transgene with lal−/− knockout (KO) (LAP-Tg/KO) triple mice. Hepatocyte-specific expression of hLAL in LAP-Tg/KO triple mice reduced the liver size to the normal level by decreasing lipid storage in both hepatocytes and Kupffer cells. hLAL expression reduced tumor-promoting myeloid-derived suppressive cells in the liver of lal−/− mice. As a result, B16 melanoma metastasis to the liver was almost completely blocked. Expression and secretion of multiple tumor-promoting cytokines or chemokines in the liver were also significantly reduced. Because hLAL is a secretory protein, lal−/− phenotypes in other compartments (eg, blood, spleen, and lung) also ameliorated, including systemic reduction of myeloid-derived suppressive cells, an increase in CD4+ and CD8+ T and B lymphocytes, and reduced B16 melanoma metastasis in the lung. These results support a concept that LAL in hepatocytes is a critical metabolic enzyme in controlling neutral lipid metabolism, liver homeostasis, immune response, and tumor metastasis. PMID:26212911

  7. Diversity of the lactic acid bacterium and yeast microbiota in the switch from firm- to liquid-sourdough fermentation.

    PubMed

    Di Cagno, Raffaella; Pontonio, Erica; Buchin, Solange; De Angelis, Maria; Lattanzi, Anna; Valerio, Francesca; Gobbetti, Marco; Calasso, Maria

    2014-05-01

    Four traditional type I sourdoughs were comparatively propagated (28 days) under firm (dough yield, 160) and liquid (dough yield, 280) conditions to mimic the alternative technology options frequently used for making baked goods. After 28 days of propagation, liquid sourdoughs had the lowest pH and total titratable acidity (TTA), the lowest concentrations of lactic and acetic acids and free amino acids, and the most stable density of presumptive lactic acid bacteria. The cell density of yeasts was the highest in liquid sourdoughs. Liquid sourdoughs showed simplified microbial diversity and harbored a low number of strains, which were persistent. Lactobacillus plantarum dominated firm sourdoughs over time. Leuconostoc lactis and Lactobacillus brevis dominated only some firm sourdoughs, and Lactobacillus sanfranciscensis persisted for some time only in some firm sourdoughs. Leuconostoc citreum persisted in all firm and liquid sourdoughs, and it was the only species detected in liquid sourdoughs at all times; it was flanked by Leuconostoc mesenteroides in some sourdoughs. Saccharomyces cerevisiae, Candida humilis, Saccharomyces servazzii, Saccharomyces bayanus-Kazachstania sp., and Torulaspora delbrueckii were variously identified in firm and liquid sourdoughs. A total of 197 volatile components were identified through purge and trap-/solid-phase microextraction-gas chromatography-mass spectrometry (PT-/SPME-GC-MS). Aldehydes, several alcohols, and some esters were at the highest levels in liquid sourdoughs. Firm sourdoughs mainly contained ethyl acetate, acetic acid, some sulfur compounds, and terpenes. The use of liquid fermentation would change the main microbial and biochemical features of traditional baked goods, which have been manufactured under firm conditions for a long time.

  8. Thermic sealing in femoral catheterisation: First experience with the Secure Device.

    PubMed

    Sacherer, Michael; Kolesnik, Ewald; von Lewinski, Friederike; Verheyen, Nicolas; Brandner, Karin; Wallner, Markus; Eaton, Deborah M; Luha, Olev; Zweiker, Robert; von Lewinski, Dirk

    2018-04-03

    Devices currently used to achieve hemostasis of the femoral artery following percutaneous cardiac catheterization are associated with vascular complications and remnants of artificial materials are retained at the puncture site. The SECURE arterial closure device induces hemostasis by utilizing thermal energy, which causes collagen shrinking and swelling. In comparison to established devices, it has the advantage of leaving no foreign material in the body following closing. This study was designed to evaluate the efficacy and safety of the SECURE device to close the puncture site following percutaneous cardiac catheterization. The SECURE device was evaluated in a prospective non-randomized single-centre trial with patients undergoing 6 F invasive cardiac procedures. A total of 67 patients were enrolled and the device was utilized in 63 patients. 50 diagnostic and 13 interventional cases were evaluated. Femoral artery puncture closure was performed immediately after completion of the procedure. Time to hemostasis (TTH), time to ambulation (TTA) and data regarding short-term and 30-day clinical follow-up were recorded. Mean TTH was 4:30 ± 2:15 min in the overall observational group. A subpopulation of patients receiving anticoagulants had a TTH of 4:53 ± 1:43 min. There were two access site complications (hematoma > 5 cm). No major adverse events were identified during hospitalization or at the 30 day follow-up. The new SECURE device demonstrates that it is feasible in diagnostic and interventional cardiac catheterization. With respect to safety, the SECURE device was non-inferior to other closure devices as tested in the ISAR closure trial.

  9. Diversity of the Lactic Acid Bacterium and Yeast Microbiota in the Switch from Firm- to Liquid-Sourdough Fermentation

    PubMed Central

    Di Cagno, Raffaella; Pontonio, Erica; Buchin, Solange; De Angelis, Maria; Lattanzi, Anna; Valerio, Francesca; Calasso, Maria

    2014-01-01

    Four traditional type I sourdoughs were comparatively propagated (28 days) under firm (dough yield, 160) and liquid (dough yield, 280) conditions to mimic the alternative technology options frequently used for making baked goods. After 28 days of propagation, liquid sourdoughs had the lowest pH and total titratable acidity (TTA), the lowest concentrations of lactic and acetic acids and free amino acids, and the most stable density of presumptive lactic acid bacteria. The cell density of yeasts was the highest in liquid sourdoughs. Liquid sourdoughs showed simplified microbial diversity and harbored a low number of strains, which were persistent. Lactobacillus plantarum dominated firm sourdoughs over time. Leuconostoc lactis and Lactobacillus brevis dominated only some firm sourdoughs, and Lactobacillus sanfranciscensis persisted for some time only in some firm sourdoughs. Leuconostoc citreum persisted in all firm and liquid sourdoughs, and it was the only species detected in liquid sourdoughs at all times; it was flanked by Leuconostoc mesenteroides in some sourdoughs. Saccharomyces cerevisiae, Candida humilis, Saccharomyces servazzii, Saccharomyces bayanus-Kazachstania sp., and Torulaspora delbrueckii were variously identified in firm and liquid sourdoughs. A total of 197 volatile components were identified through purge and trap–/solid-phase microextraction–gas chromatography-mass spectrometry (PT–/SPME–GC-MS). Aldehydes, several alcohols, and some esters were at the highest levels in liquid sourdoughs. Firm sourdoughs mainly contained ethyl acetate, acetic acid, some sulfur compounds, and terpenes. The use of liquid fermentation would change the main microbial and biochemical features of traditional baked goods, which have been manufactured under firm conditions for a long time. PMID:24632249

  10. The effect of vacuum assisted socket suspension on prospective, community-based falls by users of lower limb prostheses.

    PubMed

    Rosenblatt, Noah J; Ehrhardt, Tess

    2017-06-01

    Individuals with lower limb amputation are at increased risk of falling compared to age-matched peers. The purpose of this study was to quantify the effect of socket suspension on the risk of falling, by comparing prospectively tracked falls between a group of participants that used vacuum assisted socket suspension (VASS) and a group that did not use this system. Fifteen current users of VASS and 12 non-VASS users received an email every two weeks for one year, with a link to an online survey that asked whether they fell (i.e., "unintentionally came to rest on a lower surface") or stumbled (i.e., lost balance but did not fall) in the prior two weeks. A Chi-squared test was used to compare fall and stumble risk between groups, after stratifying by level of amputation, and the phi coefficient (φ) was used to quantify effect size. While the use of VASS did not affect the rate of falling (i.e., falls per person year) for either persons with transtibial amputation (TTA) or those with transfemoral amputation (TFA), the absolute risk of having multiple falls was reduced by nearly 75% in the former (φ=0.83), which is particularly important given that recurrent falls are associated with more severe injuries. There was no effect of VASS on the risk of falls in TFA. Further work is warranted to demonstrate the persistence of these effects in larger, more controlled samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Triplet-sensitized photon upconversion in deep eutectic solvents.

    PubMed

    Murakami, Yoichi; Das, Sudhir Kumar; Himuro, Yuki; Maeda, Satoshi

    2017-11-22

    Photon upconversion (UC) is a technology that can increase solar utilization efficiencies in broad photoenergy conversion systems by converting lower-energy photons into usable higher-energy photons. Recently, UC using triplet-triplet annihilation (TTA) of organic molecules has drawn attention because it is presently the only method applicable to weak and noncoherent light. To date, many attempts have been made to realize this UC technology in forms suitable for applications, but they typically suffer from either high cost or insufficient stability and/or safety of materials. Recently, a new class of liquid called deep eutectic solvents (DESs) has emerged as low-cost green fluids that possess low toxicity and vapor pressure, biodegradability, and high thermal stability. DESs have been proposed as an alternative to ionic liquids. This article develops triplet-sensitized UC samples using DESs that are found to be suitable solvents for this purpose, attaining a new materials platform for UC with the aforementioned advantages. The high thermal stability of the samples is qualitatively confirmed and their UC quantum yields are determined to be 0.11-0.21 (based on the definition that the maximum quantum yield is 0.5) depending on the DES composition. The triplet lifetime of the emitter 9,10-diphenylanthracene increases with DES viscosity, resulting in unique kinetics. Analysis of photophysical experimental results allows the relevant physics governing the performance of this sample system to be determined and discussed. Overall, a novel UC platform that simultaneously achieves high thermal stability, low cost, and environmental friendliness is developed using DESs as the solvent.

  12. Evolutionary genomics of miniature inverted-repeat transposable elements (MITEs) in Brassica.

    PubMed

    Nouroz, Faisal; Noreen, Shumaila; Heslop-Harrison, J S

    2015-12-01

    Miniature inverted-repeat transposable elements (MITEs) are truncated derivatives of autonomous DNA transposons, and are dispersed abundantly in most eukaryotic genomes. We aimed to characterize various MITEs families in Brassica in terms of their presence, sequence characteristics and evolutionary activity. Dot plot analyses involving comparison of homoeologous bacterial artificial chromosome (BAC) sequences allowed identification of 15 novel families of mobile MITEs. Of which, 5 were Stowaway-like with TA Target Site Duplications (TSDs), 4 Tourist-like with TAA/TTA TSDs, 5 Mutator-like with 9-10 bp TSDs and 1 novel MITE (BoXMITE1) flanked by 3 bp TSDs. Our data suggested that there are about 30,000 MITE-related sequences in Brassica rapa and B. oleracea genomes. In situ hybridization showed one abundant family was dispersed in the A-genome, while another was located near 45S rDNA sites. PCR analysis using primers flanking sequences of MITE elements detected MITE insertion polymorphisms between and within the three Brassica (AA, BB, CC) genomes, with many insertions being specific to single genomes and others showing evidence of more recent evolutionary insertions. Our BAC sequence comparison strategy enables identification of evolutionarily active MITEs with no prior knowledge of MITE sequences. The details of MITE families reported in Brassica enable their identification, characterization and annotation. Insertion polymorphisms of MITEs and their transposition activity indicated important mechanism of genome evolution and diversification. MITE families derived from known Mariner, Harbinger and Mutator DNA transposons were discovered, as well as some novel structures. The identification of Brassica MITEs will have broad applications in Brassica genomics, breeding, hybridization and phylogeny through their use as DNA markers.

  13. A synthetic data set of high-spectral-resolution infrared spectra for the Arctic atmosphere

    NASA Astrophysics Data System (ADS)

    Cox, Christopher J.; Rowe, Penny M.; Neshyba, Steven P.; Walden, Von P.

    2016-05-01

    Cloud microphysical and macrophysical properties are critical for understanding the role of clouds in climate. These properties are commonly retrieved from ground-based and satellite-based infrared remote sensing instruments. However, retrieval uncertainties are difficult to quantify without a standard for comparison. This is particularly true over the polar regions, where surface-based data for a cloud climatology are sparse, yet clouds represent a major source of uncertainty in weather and climate models. We describe a synthetic high-spectral-resolution infrared data set that is designed to facilitate validation and development of cloud retrieval algorithms for surface- and satellite-based remote sensing instruments. Since the data set is calculated using pre-defined cloudy atmospheres, the properties of the cloud and atmospheric state are known a priori. The atmospheric state used for the simulations is drawn from radiosonde measurements made at the North Slope of Alaska (NSA) Atmospheric Radiation Measurement (ARM) site at Barrow, Alaska (71.325° N, 156.615° W), a location that is generally representative of the western Arctic. The cloud properties for each simulation are selected from statistical distributions derived from past field measurements. Upwelling (at 60 km) and downwelling (at the surface) infrared spectra are simulated for 260 cloudy cases from 50 to 3000 cm-1 (3.3 to 200 µm) at monochromatic (line-by-line) resolution at a spacing of ˜ 0.01 cm-1 using the Line-by-line Radiative Transfer Model (LBLRTM) and the discrete-ordinate-method radiative transfer code (DISORT). These spectra are freely available for interested researchers from the NSF Arctic Data Center data repository (doi:10.5065/D61J97TT).

  14. Cloning of the canine gene encoding transcription factor Pit-1 and its exclusion as candidate gene in a canine model of pituitary dwarfism.

    PubMed

    Lantinga-van Leeuwen, I S; Mol, J A; Kooistra, H S; Rijnberk, A; Breen, M; Renier, C; van Oost, B A

    2000-01-01

    Combined pituitary hormone deficiency (CPHD) is an autosomal recessive inherited disease of German shepherd dogs characterized primarily by dwarfism. In mice and humans a similar genetic disorder has been described that results from an alteration in the gene encoding the transcription factor Pit-1. In this study we characterized the canine Pit-1 gene, determined the chromosomal localization of the Pit-1 gene, and screened dwarf German shepherd dogs for the presence of mutations in this gene. The full-length canine Pit-1 cDNA contained an open reading frame encoding 291 amino acids, 92 bp of 5'-untranslated region, and 1959 bp of 3'-untranslated region. The deduced amino acid sequence was highly homologous with Pit-1 of other mammalian species. Using a Pit-1 BAC clone as probe, the Pit-1 gene was mapped by FISH to canine Chromosome (Chr) 31. In dwarf German shepherd dogs a C to A transversion was detected, causing a Phe (TTC) to Leu (TTA) substitution at codon 81. This alteration was present neither in other canine breeds analyzed nor in other mammalian species. However, healthy German shepherd dogs were also homozygous for the mutant allele, indicating that it is not the primary disease-causing mutation. In addition, linkage analysis of polymorphic DNA markers flanking the Pit-1 gene, 41K19 and 52L05, revealed no co-segregation between the Pit-1 locus and the CPHD phenotype. These findings suggest that a gene other than Pit-1 is responsible for the pituitary anomaly in dwarf German shepherd dogs.

  15. Designing a Dy2 Single-Molecule Magnet with Two Well-Differentiated Relaxation Processes by Using a Nonsymmetric Bis-bidentate Bipyrimidine- N-Oxide Ligand: A Comparison with Mononuclear Counterparts.

    PubMed

    Díaz-Ortega, Ismael F; Herrera, Juan Manuel; Aravena, Daniel; Ruiz, Eliseo; Gupta, Tulika; Rajaraman, Gopalan; Nojiri, H; Colacio, Enrique

    2018-06-04

    Herein we report a dinuclear [(μ-mbpymNO){(tmh) 3 Dy} 2 ] (1) single-molecule magnet (SMM) showing two nonequivalent Dy III centers, which was rationally prepared from the reaction of Dy(tmh) 3 moieties (tmh = 2,2,6,6-tetramethyl-3,5-heptanedionate) and the asymmetric bis-bidentate bridging ligand 4-methylbipyrimidine (mbpymNO). Depending on whether the Dy III ions coordinate to the N^O or N^N bidentate donor sets, the Dy III sites present a NO 7 ( D 2 d geometry) or N 2 O 6 ( D 4 d ) coordination sphere. As a consequence, two different thermally activated magnetic relaxation processes are observed with anisotropy barriers of 47.8 and 54.7 K. Ab initio calculations confirm the existence of two different relaxation phenomena and allow one to assign the 47.8 and 54.7 K energy barriers to the Dy(N 2 O 6 ) and Dy(NO 7 ) sites, respectively. Two mononuclear complexes, [Dy(tta) 3 (mbpymNO)] (2) and [Dy(tmh) 3 (phenNO)] (3), have also been prepared for comparative purposes. In both cases, the Dy III center shows a NO 7 coordination sphere and SMM behavior is observed with U eff values of 71.5 K (2) and 120.7 K (3). In all three cases, ab initio calculations indicate that relaxation of the magnetization takes place mainly via the first excited-state Kramers doublet through Orbach, Raman, and thermally assisted quantum-tunnelling mechanisms. Pulse magnetization measurements reveal that the dinuclear and mononuclear complexes exhibit hysteresis loops with double- and single-step structures, respectively, thus supporting their SMM behavior.

  16. Distal tibial tuberosity translation using TTA implants for the treatment of patella alta in large breed dogs. Surgical technique and clinical outcome.

    PubMed

    Pugliese, L C; Pike, F S; Aiken, S W

    2015-01-01

    Medial patellar luxation frequently occurs in dogs resulting in lameness with increasing incidence in large breed dogs. Patella alta has been defined as a patellar ligament length to patellar length ratio that is greater than two and may predispose to patellar luxation. To describe the surgical technique for stabilization of the distal translation of the tibial tuberosity using tibial tuberosity advancement plates and the clinical outcomes with follow-up for clinical cases of dogs. Dogs that were presented with the complaint of patellar luxation and that were concurrently diagnosed with patella alta and were greater than 20 kg in body weight underwent surgery using a tibial tuberosity advancement plate to stabilize the osteotomy. Radiographic assessment of A:PL distance (the ratio of the proximal aspect of the patella to the femoral condyle [A] to the patellar length [PL]), L:P ratio (ratio of the length of the patellar ligament to the diagonal length of the patella), and owner assessment were obtained. Eleven stifles in nine dogs underwent surgical correction with a mean preoperative L:P ratio of 2.47. There were no complications and the lameness resolved clinically. The mean A:PL ratios preoperatively (2.6 ± 0.22) and postoperatively (2.1 ± 0.25) were significantly different (p = 0.0003). All owners were satisfied with the outcome and all dogs had a resolution of lameness with no recurrence of patellar luxation. Stabilization of distal translation of the tibial tuberosity using tibial tuberosity advancement implants to correct patella alta in large breed dogs was feasible and resulted in good clinical outcome.

  17. Assembly of 1D nanofibers into a 2D bi-layered composite nanofibrous film with different functionalities at the two layers via layer-by-layer electrospinning.

    PubMed

    Wang, Zijiao; Ma, Qianli; Dong, Xiangting; Li, Dan; Xi, Xue; Yu, Wensheng; Wang, Jinxian; Liu, Guixia

    2016-12-21

    A two-dimensional (2D) bi-layered composite nanofibrous film assembled by one-dimensional (1D) nanofibers with trifunctionality of electrical conduction, magnetism and photoluminescence has been successfully fabricated by layer-by-layer electrospinning. The composite film consists of a polyaniline (PANI)/Fe 3 O 4 nanoparticle (NP)/polyacrylonitrile (PAN) tuned electrical-magnetic bifunctional layer on one side and a Tb(TTA) 3 (TPPO) 2 /polyvinylpyrrolidone (PVP) photoluminescent layer on the other side, and the two layers are tightly combined face-to-face together into the novel bi-layered composite film of trifunctionality. The brand-new film has totally different characteristics at the double layers. The electrical conductivity and magnetism of the electrical-magnetic bifunctional layer can be, respectively, tunable via modulating the PANI and Fe 3 O 4 NP contents, and the highest electrical conductivity can reach up to the order of 10 -2 S cm -1 , and predominant intense green emission at 545 nm is obviously observed in the photoluminescent layer under the excitation of 357 nm single-wavelength ultraviolet light. More importantly, the luminescence intensity of the photoluminescent layer remains almost unaffected by the electrical-magnetic bifunctional layer because the photoluminescent materials have been successfully isolated from dark-colored PANI and Fe 3 O 4 NPs. By comparing with the counterpart single-layered composite nanofibrous film, it is found that the bi-layered composite nanofibrous film has better performance. The novel bi-layered composite nanofibrous film with trifunctionality has potential in the fields of nanodevices, molecular electronics and biomedicine. Furthermore, the design conception and fabrication technique for the bi-layered multifunctional film provide a new and facile strategy towards other films of multifunctionality.

  18. Triplet photosensitizers: from molecular design to applications.

    PubMed

    Zhao, Jianzhang; Wu, Wanhua; Sun, Jifu; Guo, Song

    2013-06-21

    Triplet photosensitizers (PSs) are compounds that can be efficiently excited to the triplet excited state which subsequently act as catalysts in photochemical reactions. The name is originally derived from compounds that were used to transfer the triplet energy to other compounds that have only a small intrinsic triplet state yield. Triplet PSs are not only used for triplet energy transfer, but also for photocatalytic organic reactions, photodynamic therapy (PDT), photoinduced hydrogen production from water and triplet-triplet annihilation (TTA) upconversion. A good PS should exhibit strong absorption of the excitation light, a high yield of intersystem crossing (ISC) for efficient production of the triplet state, and a long triplet lifetime to allow for the reaction with a reactant molecule. Most transition metal complexes show efficient ISC, but small molar absorption coefficients in the visible spectral region and short-lived triplet excited states, which make them unsuitable as triplet PSs. One obstacle to the development of new triplet PSs is the difficulty in predicting the ISC of chromophores, especially of organic compounds without any heavy atoms. This review article summarizes some molecular design rationales for triplet PSs, based on the molecular structural factors that facilitate ISC. The design of transition metal complexes with large molar absorption coefficients in the visible spectral region and long-lived triplet excited states is presented. A new method of using a spin converter to construct heavy atom-free organic triplet PSs is discussed, with which ISC becomes predictable, C60 being an example. To enhance the performance of triplet PSs, energy funneling based triplet PSs are proposed, which show broadband absorption in the visible region. Applications of triplet PSs in photocatalytic organic reactions, hydrogen production, triplet-triplet annihilation upconversion and luminescent oxygen sensing are briefly introduced.

  19. Solvation molar enthalpies and heat capacities of n-alkanes and n-alkylbenzenes on stationary phases of wide-ranging polarity.

    PubMed

    Lebrón-Aguilar, Rosa; Quintanilla-López, Jesús Eduardo; Santiuste, José María

    2010-12-03

    A comparison of the most usual gas chromatographic methods for the calculation of partial molar enthalpies of solvation (Δ(sol)H(o)) has been carried out. Those methods based on the fitting of lnV(g) or ln(k/T) vs. 1/T and ln(k/T) vs. (1/T and the temperature arrangement, T(a)) are the most adequate ones for obtaining Δ(sol)H(o) values. However, the latter is the only reliable option for Δ(sol)H(o) estimation when commercial WCOT capillary columns are used, since in this case the estimation of some variables involved in the V(g) determination is less accurate or even impossible. Consequently, in this paper, Δ(sol)H(o) obtained from ln(k/T) vs. (1/T+T(a)) fitting at 373.15 and 298.15K for n-alkanes and n-alkylbenzenes on 12 commercial capillary columns coated with stationary phases covering the 203-3608 McReynolds polarity range are reported. Moreover, molar heat capacities of solvation at constant pressure (Δ(sol)C(p)(o)) have also been calculated using this method. A clear influence on Δ(sol)H(o) of the type and content of the substitution group in the stationary phase was observed. In addition, a linear relationship of Δ(sol)C(p)(o) with the van der Waals volume of the n-alkanes and the temperature gradient of density of the stationary phase was found. The effect of the size of the hydrocarbon on both thermodynamic variables was also investigated. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. The complete mitochondrial genome of Setaria digitata (Nematoda: Filarioidea): Mitochondrial gene content, arrangement and composition compared with other nematodes.

    PubMed

    Yatawara, Lalani; Wickramasinghe, Susiji; Rajapakse, R P V J; Agatsuma, Takeshi

    2010-09-01

    In the present study, we determined the complete mitochondrial (mt) genome sequence (13,839bp) of parasitic nematode Setaria digitata and its structure and organization compared with Onchocerca volvulus, Dirofilaria immitis and Brugia malayi. The mt genome of S. digitata is slightly larger than the mt genomes of other filarial nematodes. S. digitata mt genome contains 36 genes (12 protein-coding genes, 22 transfer RNAs and 2 ribosomal RNAs) that are typically found in metazoans. This genome contains a high A+T (75.1%) content and low G+C content (24.9%). The mt gene order for S. digitata is the same as those for O. volvulus, D. immitis and B. malayi but it is distinctly different from other nematodes compared. The start codons inferred in the mt genome of S. digitata are TTT, ATT, TTG, ATG, GTT and ATA. Interestingly, the initiation codon TTT is unique to S. digitata mt genome and four protein-coding genes use this codon as a translation initiation codon. Five protein-coding genes use TAG as a stop codon whereas three genes use TAA and four genes use T as a termination codon. Out of 64 possible codons, only 57 are used for mitochondrial protein-coding genes of S. digitata. T-rich codons such as TTT (18.9%), GTT (7.9%), TTG (7.8%), TAT (7%), ATT (5.7%), TCT (4.8%) and TTA (4.1%) are used more frequently. This pattern of codon usage reflects the strong bias for T in the mt genome of S. digitata. In conclusion, the present investigation provides new molecular data for future studies of the comparative mitochondrial genomics and systematic of parasitic nematodes of socio-economic importance. 2010 Elsevier B.V. All rights reserved.

  1. Theoretical discrepancy between cage size and efficient tibial tuberosity advancement in dogs treated for cranial cruciate ligament rupture.

    PubMed

    Etchepareborde, S; Mills, J; Busoni, V; Brunel, L; Balligand, M

    2011-01-01

    To calculate the difference between the desired tibial tuberosity advancement (TTA) along the tibial plateau axis and the advancement truly achieved in that direction when cage size has been determined using the method of Montavon and colleagues. To measure the effect of this difference on the final patellar tendon-tibial plateau angle (PTA) in relation to the ideal 90°. Trigonometry was used to calculate the theoretical actual advancement of the tibial tuberosity in a direction parallel to the tibial plateau that would be achieved by the placement of a cage at the level of the tibial tuberosity in the osteotomy plane of the tibial crest. The same principle was used to calculate the size of the cage that would have been required to achieve the desired advancement. The effect of the difference between the desired advancement and the actual advancement achieved on the final PTA was calculated. For a given desired advancement, the greater the tibial plateau angle (TPA), the greater the difference between the desired advancement and the actual advancement achieved. The maximum discrepancy calculated was 5.8 mm for a 12 mm advancement in a case of extreme TPA (59°). When the TPA was less than 31°, the PTA was in the range of 90° to 95°. A discrepancy does exist between the desired tibial tuberosity advancement and the actual advancement in a direction parallel to the TPA, when the tibial tuberosity is not translated proximally. Although this has an influence on the final PTA, further studies are warranted to evaluate whether this is clinically significant.

  2. CaV3.1 isoform of T-type calcium channels supports excitability of rat and mouse ventral tegmental area neurons.

    PubMed

    Tracy, Matthew E; Tesic, Vesna; Stamenic, Tamara Timic; Joksimovic, Srdjan M; Busquet, Nicolas; Jevtovic-Todorovic, Vesna; Todorovic, Slobodan M

    2018-03-23

    Recent data have implicated voltage-gated calcium channels in the regulation of the excitability of neurons within the mesolimbic reward system. While the attention of most research has centered on high voltage L-type calcium channel activity, the presence and role of the low voltage-gated T-type calcium channel (T-channels) has not been well explored. Hence, we investigated T-channel properties in the neurons of the ventral tegmental area (VTA) utilizing wild-type (WT) rats and mice, Ca V 3.1 knock-out (KO) mice, and TH-eGFP knock-in (KI) rats in acute horizontal brain slices of adolescent animals. In voltage-clamp experiments, we first assessed T-channel activity in WT rats with characteristic properties of voltage-dependent activation and inactivation, as well as characteristic crisscrossing patterns of macroscopic current kinetics. T-current kinetics were similar in WT mice and WT rats but T-currents were abolished in Ca V 3.1 KO mice. In ensuing current-clamp experiments, we observed the presence of hyperpolarization-induced rebound burst firing in a subset of neurons in WT rats, as well as dopaminergic and non-dopaminergic neurons in TH-eGFP KI rats. Following the application of a pan-selective T-channel blocker TTA-P2, rebound bursting was significantly inhibited in all tested cells. In a behavioral assessment, the acute locomotor increase induced by a MK-801 (Dizocilpine) injection in WT mice was abolished in Ca V 3.1 KO mice, suggesting a tangible role for 3.1 T-type channels in drug response. We conclude that pharmacological targeting of Ca V 3.1 isoform of T-channels may be a novel approach for the treatment of disorders of mesolimbic reward system. Copyright © 2018. Published by Elsevier Ltd.

  3. Selection of functional lactic acid bacteria as starter cultures for the fermentation of Korean leek (Allium tuberosum Rottler ex Sprengel.).

    PubMed

    Yang, Jaesik; Ji, Yosep; Park, Hyunjoon; Lee, Jieun; Park, Soyoung; Yeo, Soyoung; Shin, Hyunkil; Holzapfel, Wilhelm H

    2014-11-17

    The purpose of this research was to find safe and suitable starter cultures for the fermentation of Korean leek (Allium tuberosum Rottler), also known as garlic chives or Oriental garlic. This traditional herb has several functional properties and a strong flavour; its leaves are used as food material. Eighteen strains of lactic acid bacteria (LAB) were isolated from well-fermented leek kimchi. Controlled fermentation of the leek leaves was conducted with 2 strains (Weissella confusa LK4 and Lactobacillus plantarum LK8), selected as potential starter cultures on the basis of their safety properties, and on the pH, total titratable acidity (TTA), and viable cell numbers [colony forming units (CFUml(-1))] achieved during the fermentation. Microbial dynamics was also followed during fermentation by using PCR-DGGE (Denaturing Gradient Gel Electrophoresis) on DNA level. To analyse bioactive compounds such as thiols and allicin (diallyl thiosulfinates), the total flavonoid and polyphenolic contents were determined by colorimetric methods. Functional properties were assessed on the basis of anti-oxidative capacities by determining the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging effect, and ferric reducing antioxidant power (FRAP). W. confusa LK4 rapidly increased during the first stage of leek fermentation, and was mainly responsible for accelerated fermentation during the early period in contrast to L. plantarum LK8, a stronger acid producer during the later stages of fermentation. After 48 h fermentation, leeks fermented with W. confusa LK4 showed the highest radical scavenging effects and reducing ability. The detectable amount of allicin of fermented leeks decreased relative to the change in pH, whereas the concentration of thiols significantly increased. Total flavonoid and poly-phenolic contents changed during fermentation and showed correlation with anti-oxidant effects. We therefore suggest the suitability of W. confusa LK4 as a potential starter culture for fermentation of leeks. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Codominance of Lactobacillus plantarum and obligate heterofermentative lactic acid bacteria during sourdough fermentation.

    PubMed

    Ventimiglia, Giusi; Alfonzo, Antonio; Galluzzo, Paola; Corona, Onofrio; Francesca, Nicola; Caracappa, Santo; Moschetti, Giancarlo; Settanni, Luca

    2015-10-01

    Fifteen sourdoughs produced in western Sicily (southern Italy) were analysed by classical methods for their chemico-physical characteristics and the levels of lactic acid bacteria (LAB). pH and total titratable acidity (TTA) were mostly in the range commonly reported for similar products produced in Italy, but the fermentation quotient (FQ) of the majority of samples was above 4.0, due to the low concentration of acetic acid estimated by high performance liquid chromatography (HPLC). Specific counts of LAB showed levels higher than 10(8) CFU g(-1) for many samples. The colonies representing various morphologies were isolated and, after the differentiation based on phenotypic characteristics, divided into 10 groups. The most numerous group was composed of facultative heterofermentative isolates, indicating a relevance of this bacterial group during fermentation. The genetic analysis by randomly amplified polymorphic DNA (RAPD)-PCR, 16S rRNA gene sequencing and species-specific PCRs identified 33 strains as Lactobacillus plantarum, Lactobacillus curvatus and Lactobacillus graminis. Due to the consistent presence of L. plantarum, it was concluded that this species codominates with obligate heterofermentative LAB in sourdough production in this geographical area. In order to evaluate the performances at the basis of their fitness, the 29 L. plantarum strains were investigated for several technological traits. Twelve cultures showed good acidifying abilities in vitro and L. plantarum PON100148 produced the highest concentrations of organic acids. Eleven strains were positive for extracellular protease activity. Bacteriocin-like inhibitory substances (BLIS) production and antifungal activity was scored positive for several strains, included L. plantarum PON100148 which was selected as starter for experimental sourdough production. The characteristics of the sourdoughs and the resulting breads indicated that the best productions were obtained in presence of L. plantarum PON100148. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Voltammetric behaviour of free DNA bases, methylcytosine and oligonucleotides at disposable screen printed graphite electrode platforms.

    PubMed

    Brotons, Ariadna; Mas, Luis Alcaraz; Metters, Jonathan P; Banks, Craig E; Iniesta, Jesús

    2013-09-21

    Improvements in analytical methods for the determination and quantification of methylcytosine in DNA are vital since it has the potential to be used as a biomarker to detect different diseases in the first stage such as in the case of carcinomas and sterility. In this work we utilized screen printed graphite electrodes (SPGE) for studying the electrochemical response of all free DNA bases, methylcytosine and short oligonucleotides by cyclic voltammetry (CV) and square wave voltammetry (SWV). CV and SWV responses of free DNA bases and methylcytosine have been investigated by using SPGE platforms and the feasibility of detecting and quantifying cytosine and methylcytosine as free DNA moieties has been evaluated as a function of pH, concentration and the presence of the other free DNA bases in solution simultaneously. Repeatability of using SWV has been performed for the electrochemical behavior of both 250 μM cytosine and 250 μM methylcytosine in the presence of 25 μM guanine, with coefficient of variations of 6.9% and 2.6% respectively based upon peak current (N = 5). Six-mer oligonucleotides with a sequence 5'-XXXCGC-3', where the XXX motif corresponds to TTT, TTA, TAA and AAA have been performed using SWV in 0.1 M acetate buffer pH 5.0 to explore how the DNA base position effects the electrooxidation of guanine and cytosine into the oligonucleotide. Furthermore SWV comparisons of the electrooxidation of the oligonucleotides 5'-CGCGCG-3' and its methylated 5'-mCGmCGmCG-3' have been performed with concentrations in acetate buffer solutions, and the interaction of both oligonucleotides with the graphitic surface of the SPGE has been demonstrated by fitting well-known adsorption models such as Freundlich and Langmuir kinetics according to the SWV current response of guanine, cytosine and methylcytosine into the oligonucleotide.

  6. Application of the multiplex PCR method for discrimination of Artemisia iwayomogi from other Artemisia herbs.

    PubMed

    Lee, Mi Young; Doh, Eui Jeong; Kim, Eung Soo; Kim, Young Wha; Ko, Byong Seob; Oh, Seung-Eun

    2008-04-01

    Some plants classified in the genus Artemisia are used for medicinal purposes. In particular, A. iwayomogi, which is referred to as 'Haninjin,' is used as an important medicinal material in traditional Korean medicine. However, A. capillaris, and both A. argyi and A. princeps, referred to as 'Injinho' and 'Aeyup,' respectively, are used for purposes other than those for which 'Haninjin' is utilized. However, it is occasionally difficult to differentiate 'Haninjin' from 'Injinho' and/or 'Aeyup' on the basis of their morphological features, particularly when in the dried and/or sliced form. Therefore, the development of a reliable method by which to discriminate 'Haninjin' from other Artemisia herbs, especially 'Injinho' and 'Aeyup,' is clearly necessary. We recently determined that the RAPD (random amplified polymorphic DNA) technique can be used to discriminate efficiently between some Artemisia herbs. In particular, when applied to RAPD, the non-specific UBC primer 391 (5'-GCG AAC CTC G-3') was demonstrated to amplify PCR products specific to A. iwayomogi. Based on the nucleotide sequences of the PCR product, we designed a 2F1 (5'-ACC TCG GAC CTA AAT ACA-3')/ 2F3 (5'-TTA TGA TTC ATG TTC AAT TC-3') primer set to amplify a SCAR (sequence-characterized amplified region) marker of A. iwayomogi. Employing this primer set, along with two other primer sets amplifying SCAR markers of 'Aeyup' (A. argyi and A. princeps) and both 'Injinho' (A. capillaris) and A. japonica, which are classified into the same subgroup in a phenogram constructed from RAPD analysis, we developed a multiplex PCR method by which A. iwayomogi could be discriminated with certainty from other Artemisia herbs. Via this method, we determined not only whether the tested Artemisia herb was A. iwayomogi, but also which Artemisia herbs were tested concurrently with A. iwayomogi.

  7. Quantitative mouse brain phenotyping based on single and multispectral MR protocols

    PubMed Central

    Badea, Alexandra; Gewalt, Sally; Avants, Brian B.; Cook, James J.; Johnson, G. Allan

    2013-01-01

    Sophisticated image analysis methods have been developed for the human brain, but such tools still need to be adapted and optimized for quantitative small animal imaging. We propose a framework for quantitative anatomical phenotyping in mouse models of neurological and psychiatric conditions. The framework encompasses an atlas space, image acquisition protocols, and software tools to register images into this space. We show that a suite of segmentation tools (Avants, Epstein et al., 2008) designed for human neuroimaging can be incorporated into a pipeline for segmenting mouse brain images acquired with multispectral magnetic resonance imaging (MR) protocols. We present a flexible approach for segmenting such hyperimages, optimizing registration, and identifying optimal combinations of image channels for particular structures. Brain imaging with T1, T2* and T2 contrasts yielded accuracy in the range of 83% for hippocampus and caudate putamen (Hc and CPu), but only 54% in white matter tracts, and 44% for the ventricles. The addition of diffusion tensor parameter images improved accuracy for large gray matter structures (by >5%), white matter (10%), and ventricles (15%). The use of Markov random field segmentation further improved overall accuracy in the C57BL/6 strain by 6%; so Dice coefficients for Hc and CPu reached 93%, for white matter 79%, for ventricles 68%, and for substantia nigra 80%. We demonstrate the segmentation pipeline for the widely used C57BL/6 strain, and two test strains (BXD29, APP/TTA). This approach appears promising for characterizing temporal changes in mouse models of human neurological and psychiatric conditions, and may provide anatomical constraints for other preclinical imaging, e.g. fMRI and molecular imaging. This is the first demonstration that multiple MR imaging modalities combined with multivariate segmentation methods lead to significant improvements in anatomical segmentation in the mouse brain. PMID:22836174

  8. Specific primer design of mitochondrial 12S rRNA for species identification in raw meats

    NASA Astrophysics Data System (ADS)

    Cahyadi, M.; Puruhita; Barido, F. H.; Hertanto, B. S.

    2018-01-01

    Polymerase chain reaction (PCR) is a molecular technique that widely used in agriculture area including species identification in animal-based products for halalness and food safety reasons. Amplification of DNA using PCR needs a primer pair (forward and reverse primers) to isolate specific DNA fragment in the genome. This objective of this study was to design specific primer from mitochondrial 12S rRNA region for species identification in raw beef, pork and chicken meat. Three published sequences, HQ184045, JN601075, and KT626857, were downloaded from National Center for Biotechnology Information (NCBI) website. Furthermore, those reference sequences were used to design specific primer for bovine, pig, and chicken species using primer3 v.0.4.0. A total of 15 primer pairs were picked up from primer3 software. Of these, an universal forward primer and three reverse primers which are specific for bovine, pig, and chicken species were selected to be optimized using multiplex-PCR technique. The selected primers were namely UNIF (5’-ACC GCG GTC ATA CGA TTA AC-3’), SPR (5’-AGT GCG TCG GCT ATT GTA GG-3’), BBR (5’-GAA TTG GCA AGG GTT GGT AA-3’), and AR (5’-CGG TAT GTA CGT GCC TCA GA-3’). In addition, the PCR products were visualized using 2% agarose gels under the UV light and sequenced to be aligned with reference sequences using Clustal Omega. The result showed that those primers were specifically amplified mitochondrial 12S rRNA regions from bovine, pig, and chicken using PCR. It was indicated by the existence of 155, 357, and 611 bp of DNA bands for bovine, pig, and chicken species, respectively. Moreover, sequence analysis revealed that our sequences were identically similar with reference sequences. It can be concluded that mitochondrial 12S rRNA may be used as a genetic marker for species identification in meat products.

  9. Knockdown resistance (kdr)-like mutations in the voltage-gated sodium channel of a malaria vector Anopheles stephensi and PCR assays for their detection.

    PubMed

    Singh, Om P; Dykes, Cherry L; Lather, Manila; Agrawal, Om P; Adak, Tridibes

    2011-03-14

    Knockdown resistance (kdr) in insects, resulting from mutation(s) in the voltage-gated sodium channel (vgsc) gene is one of the mechanisms of resistance against DDT and pyrethroid-group of insecticides. The most common mutation(s) associated with knockdown resistance in insects, including anophelines, has been reported to be present at residue Leu1014 in the IIS6 transmembrane segment of the vgsc gene. This study reports the presence of two alternative kdr-like mutations, L1014S and L1014F, at this residue in a major malaria vector Anopheles stephensi and describes new PCR assays for their detection. Part of the vgsc (IIS4-S5 linker-to-IIS6 transmembrane segment) of An. stephensi collected from Alwar (Rajasthan, India) was PCR-amplified from genomic DNA, sequenced and analysed for the presence of deduced amino acid substitution(s). Analysis of DNA sequences revealed the presence of two alternative non-synonymous point mutations at L1014 residue in the IIS6 transmembrane segment of vgsc, i.e., T>C mutation on the second position and A>T mutation on the third position of the codon, leading to Leu (TTA)-to-Ser (TCA) and -Phe (TTT) amino acid substitutions, respectively. Polymerase chain reaction (PCR) assays were developed for identification of each of these two point mutations. Genotyping of An. stephensi mosquitoes from Alwar by PCR assays revealed the presence of both mutations, with a high frequency of L1014S. The PCR assays developed for detection of the kdr mutations were specific as confirmed by DNA sequencing of PCR-genotyped samples. Two alternative kdr-like mutations, L1014S and L1014F, were detected in An. stephensi with a high allelic frequency of L1014S. The occurrence of L1014S is being reported for the first time in An. stephensi. Two specific PCR assays were developed for detection of two kdr-like mutations in An. stephensi.

  10. Alterations of the PPP2R1B gene located at 11q23 in human colorectal cancers

    PubMed Central

    Takagi, Y; Futamura, M; Yamaguchi, K; Aoki, S; Takahashi, T; Saji, S

    2000-01-01

    BACKGROUND/AIMS—In 1998 the PPP2R1B gene encoding the A subunit of the serine/threonine protein phosphatase was identified as a putative tumour suppressor gene in lung and colon cancer in the chromosome region 11q22-24. The aim of the present study was to determine the type of alterations in primary rectal cancers as well as colon cancers and the correlation between these alterations and clinicopathological data.
METHODS—Mutation analyses of the PPP2R1B gene sequence encoding the binding sites of the catalytic C subunit (Huntington elongation A subunit TOR (HEAT) repeats 11-15) and partial binding sites of the regulatory B subunit were carried out on cDNA samples from 30 primary colorectal cancer specimens and corresponding normal tissues using a combination of the polymerase chain reaction and subsequent direct DNA sequencing.
RESULTS—Five missense mutations producing amino acid substitutions were detected in the four colon cancer cases (13.3%; four of 30 colorectal cancers): 15glycine (GGT) to alanine (GCT) and 499leucine (TTA) to isoleucine (ATA) in the same case, and 498valine (GTG) to glutamic acid (GAG), 500valine (GTA) to glycine (GGA), and 365serine (TCT) to proline (CCT). Of these five mutations, three (60%) were located in HEAT repeat 13 and four (80%) showed T to other nucleotide substitutions. In addition, a normal polymorphism, 478leucine, was found. No correlation was found between these mutations and clinicopathological data.
CONCLUSION—Our results suggest that the PPP2R1B gene is one of the true targets at 11q23, and its inactivation is involved in the development of all types of colorectal cancers.


Keywords: PPP2R1B gene; colorectal cancer; tumour suppressor gene; protein phosphatase PMID:10896920

  11. Identification of interleukin-1 beta as a key mediator in the upregulation of Cav3.2–USP5 interactions in the pain pathway

    PubMed Central

    Stemkowski, Patrick L; Garcia-Caballero, Agustin; Gadotti, Vinicius M; M’Dahoma, Said; Chen, Lina; Souza, Ivana A

    2017-01-01

    We recently reported that nerve injury or peripheral inflammation triggers an upregulation of the deubiquitinase, USP5 in mouse dorsal root ganglion and spinal dorsal horn. This leads to dysregulated ubiquitination of Cav3.2 T-type calcium channels, thus increasing Cav3.2 channel plasma membrane expression and nociceptive signaling in the primary afferent pain pathway. This phenomenon could be recapitulated by noninvasive, optogenetic activation of transient receptor potential vanilloid-1–expressing nociceptors, indicating that neuronal activity is a key player in this process. Given the relevance of the pro-inflammatory cytokine interleukin-1 beta in many forms of pathological pain, we hypothesized that interleukin-1 beta may be a critical cofactor required to drive upregulation of interactions between USP5 and Cav3.2 channels. Here, we report that gene expression, as well as protein levels for interleukin-1 beta and the endogenous interleukin-1 receptor-I antagonist, IL-1Ra are unaltered following conditioning stimulation of optogenetically targeted cutaneous nociceptors, indicating that neuronal activity is not a driver of interleukin-1 beta signaling. In contrast, co-immunoprecipitation experiments revealed that intrathecal administration of interleukin-1 beta in wild-type mice led to an increase in the interaction between USP5 and Cav3.2 in the spinal dorsal horn. Moreover, disruption of the interaction between USP5 and Cav3.2 with TAT peptides suppressed acute nocifensive responses produced by interleukin-1 beta, which was similar to that achieved by elimination of T-type channel activity with the channel blockers, mibefradil, or TTA-A2. Finally, this upregulation could be maintained in dorsal root ganglion neuron cultures exposed overnight to interleukin-1 beta, while the copresence of interleukin-1 receptor antagonist or the dampening of neuronal cell activity with tetrodotoxin attenuated this response. Altogether, our findings identify interleukin-1 beta as an upstream trigger for the upregulation of interactions between USP5 and Cav3.2 channels in the pain pathway, presumably by triggering increased firing activity in afferent fibers. PMID:28741432

  12. Antifungal sourdough lactic acid bacteria as biopreservation tool in quinoa and rice bread.

    PubMed

    Axel, Claudia; Brosnan, Brid; Zannini, Emanuele; Furey, Ambrose; Coffey, Aidan; Arendt, Elke K

    2016-12-19

    The use of sourdough fermented with specific strains of antifungal lactic acid bacteria can reduce chemical preservatives in bakery products. The main objective of this study was to investigate the production of antifungal carboxylic acids after sourdough fermentation of quinoa and rice flour using the antifungal strains Lactobacillus reuteri R29 and Lactobacillus brevis R2Δ as bioprotective cultures and the non-antifungal L. brevis L1105 as a negative control strain. The impact of the fermentation substrate was evaluated in terms of metabolic activity, acidification pattern and quantity of antifungal carboxylic acids. These in situ produced compounds (n=20) were extracted from the sourdough using a QuEChERS method and detected by a new UHPLC-MS/MS chromatography. Furthermore, the sourdough was applied in situ using durability tests against environmental moulds to investigate the biopreservative potential to prolong the shelf life of bread. Organic acid production and TTA values were lowest in rice sourdough. The sourdough fermentation of the different flour substrates generated a complex and significantly different profile of carboxylic acids. Extracted quinoa sourdough detected the greatest number of carboxylic acids (n=11) at a much higher concentration than what was detected from rice sourdough (n=9). Comparing the lactic acid bacteria strains, L. reuteri R29 fermented sourdoughs contained generally higher concentrations of acetic and lactic acid but also the carboxylic acids. Among them, 3-phenyllactic acid and 2-hydroxyisocaproic acid were present at a significant concentration. This was correlated with the superior protein content of quinoa flour and its high protease activity. With the addition of L. reuteri R29 inoculated sourdough, the shelf life was extended by 2 days for quinoa (+100%) and rice bread (+67%) when compared to the non-acidified controls. The L. brevis R2Δ fermented sourdough bread reached a shelf life of 4 days for quinoa (+100%) and rice (+33%). However, the shelf life was similar to the chemically acidified control indicating that the preservation effect of the carboxylic acids seems to have a minor contribution effect on the antifungal activity in gluten-free breads. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Haplotype analysis of the HFE gene among populations of Northern Eurasia, in patients with metabolic disorders or stomach cancer, and in long-lived people.

    PubMed

    Mikhailova, S V; Babenko, V N; Ivanoshchuk, D E; Gubina, M A; Maksimov, V N; Solovjova, I G; Voevoda, M I

    2016-06-17

    Previously, it was shown that the HFE gene (associated with human hereditary hemochromatosis) has several haplotypes of intronic polymorphisms. Some haplotype frequencies are race specific and hence can be used in phylogenetic analysis. We assumed that analysis of Caucasoid patients-living now in Western Siberia and having diseases associated with dietary habits and metabolic rate-will allow us to understand the processes of possible selection during settling of the northern part of Asia. Haplotype analysis of Northern Eurasian native and recently settled ethnic groups was performed on polymorphisms rs1799945, rs1800730, rs1800562, rs2071303, rs1800708, rs1572982, rs2794719, rs807209, and rs2032451 of this gene. The CCA haplotype of the rs2071303, rs1800708, and rs1572982 was found to be associated with HLA-A2 (39 %) in Asian populations. Haplotype analysis for the rs1799945, rs1800730, rs1800562, rs2071303, rs1800708, and rs1572982 was performed on Russian patients with some metabolic disorders or stomach cancer and among long-lived people. Decreased frequencies of the TTA haplotype (T in rs2071303, T in rs1800708, and A in rs1572982) were observed in the groups of patients with diseases associated with overweight (fatty liver disease, type 2 diabetes mellitus, or metabolic syndrome + arterial hypertension) as compared with the control sample. We detected significant differences in this haplotype's frequency between the patients with type 2 diabetes mellitus and Russian adolescents, elderly citizens, and long-lived people (χ(2) P value = 0.003, 0.010, and 0.015, respectively). No significant differences in frequencies of the alleles with mutations in coding regions of the HFE gene (C282Y, H63D, and S65C) were detected between the analyzed patients (with stomach cancer, metabolic syndrome, fatty liver disease, or type 2 diabetes mellitus) and the control Caucasoid sample. Monophyletic origin of H63D (rs1799945) was confirmed in Caucasoids and Northern Asians. The reasons for a sharp increase in the frequency of CCA haplotype of HFE in the Asian race remain unclear.

  14. Conditional transgenic mouse models: from the basics to genome-wide sets of knockouts and current studies of tissue regeneration.

    PubMed

    Bockamp, Ernesto; Sprengel, Rolf; Eshkind, Leonid; Lehmann, Thomas; Braun, Jan M; Emmrich, Frank; Hengstler, Jan G

    2008-03-01

    Many mouse models are currently available, providing avenues to elucidate gene function and to recapitulate specific pathological conditions. To a large extent, successful translation of clinical evidence or analytical data into appropriate mouse models is possible through progress in transgenic or gene-targeting technology. Beginning with a review of standard mouse transgenics and conventional gene targeting, this article will move on to discussing the basics of conditional gene expression: the tetracycline (tet)-off and tet-on systems based on the transactivators tet-controlled transactivator (Tta) and reverse tet-on transactivator (rtTA) that allow downregulation or induction of gene expression; Cre or Flp recombinase-mediated modifications, including excision, inversion, insertion and interchromosomal translocation; combination of the tet and Cre systems, permitting inducible knockout, reporter gene activation or activation of point mutations; the avian retroviral system based on delivery of rtTA specifically into cells expressing the avian retroviral receptor, which enables cell type-specific, inducible gene expression; the tamoxifen system, one of the most frequently applied steroid receptor-based systems, allows rapid activation of a fusion protein between the gene of interest and a mutant domain of the estrogen receptor, whereby activation does not depend on transcription; and techniques for cell type-specific ablation. The diphtheria toxin receptor system offers the advantage that it can be combined with the 'zoo' of Cre recombinase driver mice. Having described the basics we move on to the cutting edge: generation of genome-wide sets of conditional knockout mice. To this end, large ongoing projects apply two strategies: gene trapping based on random integration of trapping vectors into introns leading to truncation of the transcript, and gene targeting, representing the directed approach using homologous recombination. It can be expected that in the near future genome-wide sets of such mice will be available. Finally, the possibilities of conditional expression systems for investigating gene function in tissue regeneration will be illustrated by examples for neurodegenerative disease, liver regeneration and wound healing of the skin.

  15. Association between the KRAS Gene Polymorphisms and Papillary Thyroid Carcinoma in a Chinese Han Population.

    PubMed

    Ning, Lifeng; Rao, Wenwang; Yu, Yaqin; Liu, Xiaoli; Pan, Yuchen; Ma, Yuan; Liu, Rui; Zhang, Shangchao; Sun, Hui; Yu, Qiong

    2016-01-01

    Several studies have reported the association between MAPK signaling pathway gene polymorphisms and papillary thyroid carcinoma (PTC). KRAS gene, an oncogene from the mammalian RAS gene family plays an important role in the MAPK pathway. This study aimed to identify the potential association of KRAS gene polymorphisms with susceptibility to PTC in a Han Chinese population. A total of 861 patients with PTC, 562 disease controls with nodular goiter and 897 healthy controls were recruited. Four tagSNP polymorphisms (rs12427141, rs712, rs7315339 and rs7960917) of KRAS gene were genotyped by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) . Statistical analyses and haplotype estimations were conducted using Haploview and Unphased softwares. Only significant differences were observed in genotypic frequencies of the rs7315339 polymorphism (χ 2 =7.234, df=2, p=0.027) between PTC and disease controls. Statistically significant differences in both allelic and genotypic genotypes frequencies for rs712 (Genotype, χ 2 =8.258, p=0.016) and rs12427141 (Allele, χ 2 =3.992, p=0.046; Genotype, χ 2 =8.140, p=0.017) were observed between PTC patients and controls. Haplotype analyses revealed higher frequencies of GA and TA haplotypes (p=0.039 and p=0.003, respectively) from rs712- rs12427141 (two-SNP) or TGA and TTG haplotype containing the alleles from rs7960917, rs712 and rs12427141, as well as the GAT haplotype containing the alleles from rs712, rs12427141 and rs7315339 in PTC patients than in healthy controls (p=0.042, p=0.037, p=0.027, respectively). Inversely, the haplotype TTA from rs7960917, rs712 and rs12427141 or the haplotype TAC from rs712, rs12427141 and rs7315339 was significantly less frequent in the PTC patients than in normal control (p=0.003, p=0.003, respectively). These findings suggest the role of these KRAS gene variants in susceptibility to PTC. Moreover, significant differences of the KRAS gene polymorphisms may occur between nodular goiter and PTC.

  16. Modeling RNA interference in mammalian cells

    PubMed Central

    2011-01-01

    Background RNA interference (RNAi) is a regulatory cellular process that controls post-transcriptional gene silencing. During RNAi double-stranded RNA (dsRNA) induces sequence-specific degradation of homologous mRNA via the generation of smaller dsRNA oligomers of length between 21-23nt (siRNAs). siRNAs are then loaded onto the RNA-Induced Silencing multiprotein Complex (RISC), which uses the siRNA antisense strand to specifically recognize mRNA species which exhibit a complementary sequence. Once the siRNA loaded-RISC binds the target mRNA, the mRNA is cleaved and degraded, and the siRNA loaded-RISC can degrade additional mRNA molecules. Despite the widespread use of siRNAs for gene silencing, and the importance of dosage for its efficiency and to avoid off target effects, none of the numerous mathematical models proposed in literature was validated to quantitatively capture the effects of RNAi on the target mRNA degradation for different concentrations of siRNAs. Here, we address this pressing open problem performing in vitro experiments of RNAi in mammalian cells and testing and comparing different mathematical models fitting experimental data to in-silico generated data. We performed in vitro experiments in human and hamster cell lines constitutively expressing respectively EGFP protein or tTA protein, measuring both mRNA levels, by quantitative Real-Time PCR, and protein levels, by FACS analysis, for a large range of concentrations of siRNA oligomers. Results We tested and validated four different mathematical models of RNA interference by quantitatively fitting models' parameters to best capture the in vitro experimental data. We show that a simple Hill kinetic model is the most efficient way to model RNA interference. Our experimental and modeling findings clearly show that the RNAi-mediated degradation of mRNA is subject to saturation effects. Conclusions Our model has a simple mathematical form, amenable to analytical investigations and a small set of parameters with an intuitive physical meaning, that makes it a unique and reliable mathematical tool. The findings here presented will be a useful instrument for better understanding RNAi biology and as modelling tool in Systems and Synthetic Biology. PMID:21272352

  17. IT-based diagnostic instrumentation systems for personalized healthcare services.

    PubMed

    Chun, Honggu; Kang, Jaemin; Kim, Ki-Jung; Park, Kwang Suk; Kim, Hee Chan

    2005-01-01

    This paper describes recent research and development activities on the diagnostic instruments for personalized healthcare services in Seoul National University. Utilizing the state-of-the-art information technologies (IT), various diagnostic medical instruments have been integrated into a personal wearable device and a home telehealthcare system. We developed a wrist-worn integrated health monitoring device (WIHMD) which performs the measurements of non-invasive blood pressure (NIBP), pulse oximetry (SpO2), electrocardiogram (ECG), respiration rate, heart rate, and body surface temperature and the detection of falls to determine the onset of emergency situation. The WIHMD also analyzes the acquired bio-signals and transmits the resultant data to a healthcare service center through a commercial cellular phone. Two different kinds of IT-based blood glucometer have been developed using a cellular phone and PDA(personal digital assistant) as a main unit. A blood glucometer was also integrated within a wrist pressure measurement module which is interfaced with a cellular phone via Telecommunications Technology Association (TTA) standard in order to provide users with easiness in measuring and handling two important health parameters. Non-intrusive bio-signal measurement systems were developed for the ease of home use. One can measure his ECG on a bed while he is sleeping; measure his ECG, body temperature, bodyfat ratio and weight on a toilet seat; measure his ECG on a chair; and estimate the degree of activity by motion analysis using a camera. Another integrated diagnostic system for home telehealthcare services has been developed to include a 12 channels ECG, a pressure meter for NIBP, a blood glucometer, a bodyfat meter and a spirometer. It is an expert system to analyze the measured health data and based on the diagnostic result, the system provides an appropriate medical consultation. The measured data can be either stored on the system or transmitted to the central server through the internet. We have installed the developed systems on a model house for the performance evaluation and confirmed the possibility of the system as an effective tool for the personalized healthcare services.

  18. Industrial application of selected lactic acid bacteria isolated from local semolinas for typical sourdough bread production.

    PubMed

    Corona, Onofrio; Alfonzo, Antonio; Ventimiglia, Giusi; Nasca, Anna; Francesca, Nicola; Martorana, Alessandra; Moschetti, Giancarlo; Settanni, Luca

    2016-10-01

    Four obligate heterofermentative lactic acid bacteria (LAB) strains (Weissella cibaria PON10030 and PON10032 and Leuconostoc citreum PON 10079 and PON10080) were tested as single strain starters, mono-species dual strain starters, and multiple strain starter for the preparation and propagation of sourdoughs for the production of a typical bread at industrial level. The kinetics of pH and TTA during the daily sourdough refreshments indicated a correct acidification process for all trials. The concentration of lactic and acetic acid increased consistently during fermentation. The resulting molar ratios between these two organic acids in the experimental trials were lower than those observed in the control trial. The microbiological investigation showed levels of approximately 10(9) CFU/mL in almost all sourdoughs and the comparison of the genetic polymorphisms of the dominating LAB with those of the pure cultures evidenced the persistence of the added strains over time. The resulting breads were evaluated for several quality parameters. The breads with the greatest height were obtained with the quadruple combination of leuconostocs and weissellas. The highest softness was registered for the breads obtained from fermentations performed by W. cibaria PON10032 alone and in combination. The different inocula influenced also the color, the void fraction, the cell density and the mean cell area of the breads. Different levels of acids, alcohols, aldehydes, esters, hydrocarbons, ketones, terpenes, furans and phenol were emitted by the breads. The sensory tests indicated the breads from the sourdoughs fermented with the seven LAB inocula as sweeter and less acidic than control breads and the breads from the trials with the highest complexity of LAB inoculums were those more appreciated by tasters. A multivariate approach found strong differences among the trials. In particular, control breads and the breads obtained with different starter LAB were quite distant and a more strict relation was found among the productions carried out by W. cibaria strains. This study proved the suitability of the selected strains of L. citreum and W. cibaria for industrial-scale level applications in sourdough bread production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Compensatory Response by Late Embryonic Tubular Epithelium to the Reduction in Pancreatic Progenitors

    PubMed Central

    Nishimura, Wataru; Kapoor, Archana; El Khattabi, Ilham; Jin, Wanzhu; Yasuda, Kazuki; Bonner-Weir, Susan; Sharma, Arun

    2015-01-01

    Early in pancreatic development, epithelial cells of pancreatic buds function as primary multipotent progenitor cells (1°MPC) that specify all three pancreatic cell lineages, i.e., endocrine, acinar and duct. Bipotent "Trunk" progenitors derived from 1°MPC are implicated in directly regulating the specification of endocrine progenitors. It is unclear if this specification process is initiated in the 1°MPC where some 1°MPC become competent for later specification of endocrine progenitors. Previously we reported that in Pdx1 tTA/+ ;tetO MafA (bigenic) mice inducing expression of transcription factor MafA in Pdx1-expressing (Pdx1+) cells throughout embryonic development inhibited the proliferation and differentiation of 1°MPC cells, resulting in reduced pancreatic mass and endocrine cells by embryonic day (E) 17.5. Induction of the transgene only until E12.5 in Pdx1+ 1°MPC was sufficient for this inhibition of endocrine cells and pancreatic mass at E17.5. However, by birth (P0), as we now report, such bigenic pups had significantly increased pancreatic and endocrine volumes with endocrine clusters containing all pancreatic endocrine cell types. The increase in endocrine cells resulted from a higher proliferation of tubular epithelial cells expressing the progenitor marker Glut2 in E17.5 bigenic embryos and increased number of Neurog3-expressing cells at E19.5. A BrdU-labeling study demonstrated that inhibiting proliferation of 1°MPC by forced MafA-expression did not lead to retention of those progenitors in E17.5 tubular epithelium. Our data suggest that the forced MafA expression in the 1°MPC inhibits their competency to specify endocrine progenitors only until E17.5, and after that compensatory proliferation of tubular epithelium gives rise to a distinct pool of endocrine progenitors. Thus, these bigenic mice provide a novel way to characterize the competency of 1°MPC for their ability to specify endocrine progenitors, a critical limitation in our understanding of endocrine differentiation. PMID:26540252

  20. Stringent and reproducible tetracycline-regulated transgene expression by site-specific insertion at chromosomal loci with pre-characterised induction characteristics

    PubMed Central

    Brough, Rachel; Papanastasiou, Antigoni M; Porter, Andrew CG

    2007-01-01

    Background The ability to regulate transgene expression has many applications, mostly concerning the analysis of gene function. Desirable induction characteristics, such as low un-induced expression, high induced expression and limited cellular heterogeneity, can be seriously impaired by chromosomal position effects at the site of transgene integration. Many clones may therefore need to be screened before one with optimal induction characteristics is identified. Furthermore, such screens must be repeated for each new transgene investigated, and comparisons between clones with different transgenes is complicated by their different integration sites. Results To circumvent these problems we have developed a "screen and insert" strategy in which clones carrying a transgene for a fluorescent reporter are first screened for those with optimal induction characteristics. Site-specific recombination (SSR) is then be used repeatedly to insert any new transgene at the reporter transgene locus of such clones so that optimal induction characteristics are conferred upon it. Here we have tested in a human fibrosarcoma cell line (HT1080) two of many possible implementations of this approach. Clones (e.g. Rht14-10) in which a GFP reporter gene is very stringently regulated by the tetracycline (tet) transactivator (tTA) protein were first identified flow-cytometrically. Transgenes encoding luciferase, I-SceI endonuclease or Rad52 were then inserted by SSR at a LoxP site adjacent to the GFP gene resulting stringent tet-regulated transgene expression. In clone Rht14-10, increases in expression from essentially background levels (+tet) to more than 104-fold above background (-tet) were reproducibly detected after Cre-mediated insertion of either the luciferase or the I-SceI transgenes. Conclusion Although previous methods have made use of SSR to integrate transgenes at defined sites, none has effectively combined this with a pre-selection step to identify integration sites that support optimal regulatory characteristics. Rht14-10 and similar HT1080-derived clones can now be used in conjunction with a convenient delivery vector (pIN2-neoMCS), in a simple 3-step protocol leading to stringent and reproducible transgene regulation. This approach will be particularly useful for transgenes whose products are very active at low concentrations and/or for comparisons of multiple related transgenes. PMID:17493262

  1. Nonlinear optical properties, upconversion and lasing in metal-organic frameworks.

    PubMed

    Medishetty, Raghavender; Zaręba, Jan K; Mayer, David; Samoć, Marek; Fischer, Roland A

    2017-08-14

    The building block modular approach that lies behind coordination polymers (CPs) and metal-organic frameworks (MOFs) results not only in a plethora of materials that can be obtained but also in a vast array of material properties that could be aimed at. Optical properties appear to be particularly predetermined by the character of individual structural units and by the intricate interplay between them. Indeed, the "design principles" shaping the optical properties of these materials seem to be well explored for luminescence and second-harmonic generation (SHG) phenomena; these have been covered in numerous previous reviews. Herein, we shine light on CPs and MOFs as optical media for state-of-the-art photonic phenomena such as multi-photon absorption, triplet-triplet annihilation (TTA) and stimulated emission. In the first part of this review we focus on the nonlinear optical (NLO) properties of CPs and MOFs, with a closer look at the two-photon absorption property. We discuss the scope of applicability of most commonly used measurement techniques (Z-scan and two-photon excited fluorescence (TPEF)) that can be applied for proper determination of the NLO properties of these materials; in particular, we suggest recommendations for their use, along with a discussion of the best reporting practices of NLO parameters. We also outline design principles, employing both intramolecular and intermolecular strategies, that are necessary for maximizing the NLO response. A review of recent literature on two-, three- and multi-photon absorption in CPs and MOFs is further supplemented with application-oriented processes such as two-photon 3D patterning and data storage. Additionally, we provide an overview of the latest achievements in the field of frequency doubling (SHG) and tripling (third-harmonic generation, THG) in these materials. Apart from nonlinear processes, in the next sections we also target the photonic properties of MOFs that benefit from their porosity, and resulting from this their ability to serve as containers for optically-active molecules. Thus, we survey dye@MOF composites as novel media in which efficient upconversion via triplet energy migration (TEM) occurs as well as materials for stimulated emission and multi-photon pumped lasing. Prospects for producing lasing as an intrinsic property of MOFs has also been discussed. Overall, further development of the optical processes highlighted herein should allow for realization of various photonic, data storage, biomedical and optoelectronic applications.

  2. Monitoring of wheat lactic acid bacteria from the field until the first step of dough fermentation.

    PubMed

    Alfonzo, Antonio; Miceli, Claudia; Nasca, Anna; Franciosi, Elena; Ventimiglia, Giusi; Di Gerlando, Rosalia; Tuohy, Kieran; Francesca, Nicola; Moschetti, Giancarlo; Settanni, Luca

    2017-04-01

    The present work was carried out to retrieve the origin of lactic acid bacteria (LAB) in sourdough. To this purpose, wheat LAB were monitored from ear harvest until the first step of fermentation for sourdough development. The influence of the geographical area and variety on LAB species/strain composition was also determined. The ears of four Triticum durum varieties (Duilio, Iride, Saragolla and Simeto) were collected from several fields located within the Palermo province (Sicily, Italy) and microbiologically investigated. In order to trace the transfer of LAB during the consecutive steps of manipulation, ears were transformed aseptically and, after threshing, milling and fermentation, samples of kernels, semolinas and doughs, respectively, were analysed. LAB were not found to dominate the microbial communities of the raw materials. In general, kernels harboured lower levels of microorganisms than ears and ears than semolinas. Several samples showing no development of LAB colonies acidified the enrichment broth suggesting the presence of LAB below the detection limit. After fermentation, LAB loads increased consistently for all doughs, reaching levels of 7.0-7.5 Log CFU/g on M17. The values of pH (5.0) and TTA (5.6 mL NaOH/10 g of dough) indicated the occurrence of the acidification process for several doughs. LAB were phenotypically and genotypically differentiated by randomly amplified polymorphic DNA (RAPD)-PCR into eight groups including 51 strains belonging to the species Lactobacillus brevis, Lactobacillus coryniformis, Lactobacillus plantarum, Lactococcus lactis, Lactococcus garvieae, Enterococcus casseliflavus, Enterococcus faecium, Leuconostoc citreum, and Pediococcus pentosaceus. Lactobacilli constituted a minority the LAB community, while lactococci represented more than 50% of strains. Lower LAB complexity was found on kernels, while a richer biodiversity was observed in semolinas and fermented doughs. For broader microbiota characterisation in doughs before fermentation, the 16S rRNA gene fragment profiling was conducted on the unfermented doughs using MiSeq Illumina. LAB group was represented by Enterococcus, Lactococcus and members of Leuconostocaceae family whose relative abundances differed according to both geographical area and variety of wheat. The culture-independent approach confirmed that pediococci and lactobacilli constituted low abundance members of the semolina LAB microbiota and that although some strains may pass from wheat ear to fermented doughs, most are likely to come from other sources. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Allspice and Clove As Source of Triterpene Acids Activating the G Protein-Coupled Bile Acid Receptor TGR5

    PubMed Central

    Ladurner, Angela; Zehl, Martin; Grienke, Ulrike; Hofstadler, Christoph; Faur, Nadina; Pereira, Fátima C.; Berry, David; Dirsch, Verena M.; Rollinger, Judith M.

    2017-01-01

    Worldwide, metabolic diseases such as obesity and type 2 diabetes have reached epidemic proportions. A major regulator of metabolic processes that gained interest in recent years is the bile acid receptor TGR5 (Takeda G protein-coupled receptor 5). This G protein-coupled membrane receptor can be found predominantly in the intestine, where it is mainly responsible for the secretion of the incretins glucagon-like peptide 1 (GLP-1) and peptide YY (PYY). The aim of this study was (i) to identify plant extracts with TGR5-activating potential, (ii) to narrow down their activity to the responsible constituents, and (iii) to assess whether the intestinal microbiota produces transformed metabolites with a different activity profile. Chenodeoxycholic acid (CDCA) served as positive control for both, the applied cell-based luciferase reporter gene assay for TGR5 activity and the biotransformation assay using mouse fecal slurry. The suitability of the workflow was demonstrated by the biotransformation of CDCA to lithocholic acid resulting in a distinct increase in TGR5 activity. Based on a traditional Tibetan formula, 19 plant extracts were selected and investigated for TGR5 activation. Extracts from the commonly used spices Syzygium aromaticum (SaroE, clove), Pimenta dioica (PdioE, allspice), and Kaempferia galanga (KgalE, aromatic ginger) significantly increased TGR5 activity. After biotransformation, only KgalE showed significant differences in its metabolite profile, which, however, did not alter its TGR5 activity compared to non-transformed KgalE. UHPLC-HRMS (high-resolution mass spectrometry) analysis revealed triterpene acids (TTAs) as the main constituents of the extracts SaroE and PdioE. Identification and quantification of TTAs in these two extracts as well as comparison of their TGR5 activity with reconstituted TTA mixtures allowed the attribution of the TGR5 activity to TTAs. EC50s were determined for the main TTAs, i.e., oleanolic acid (2.2 ± 1.6 μM), ursolic acid (1.1 ± 0.2 μM), as well as for the hitherto unknown TGR5 activators corosolic acid (0.5 ± 1.0 μM) and maslinic acid (3.7 ± 0.7 μM). In conclusion, extracts of clove, allspice, and aromatic ginger activate TGR5, which might play a pivotal role in their therapeutic use for the treatment of metabolic diseases. Moreover, the TGR5 activation of SaroE and PdioE could be pinpointed solely to TTAs. PMID:28769799

  4. Utility of EST-derived SSR in cultivated peanut (Arachis hypogaea L.) and Arachis wild species

    PubMed Central

    Liang, Xuanqiang; Chen, Xiaoping; Hong, Yanbin; Liu, Haiyan; Zhou, Guiyuan; Li, Shaoxiong; Guo, Baozhu

    2009-01-01

    Background Lack of sufficient molecular markers hinders current genetic research in peanuts (Arachis hypogaea L.). It is necessary to develop more molecular markers for potential use in peanut genetic research. With the development of peanut EST projects, a vast amount of available EST sequence data has been generated. These data offered an opportunity to identify SSR in ESTs by data mining. Results In this study, we investigated 24,238 ESTs for the identification and development of SSR markers. In total, 881 SSRs were identified from 780 SSR-containing unique ESTs. On an average, one SSR was found per 7.3 kb of EST sequence with tri-nucleotide motifs (63.9%) being the most abundant followed by di- (32.7%), tetra- (1.7%), hexa- (1.0%) and penta-nucleotide (0.7%) repeat types. The top six motifs included AG/TC (27.7%), AAG/TTC (17.4%), AAT/TTA (11.9%), ACC/TGG (7.72%), ACT/TGA (7.26%) and AT/TA (6.3%). Based on the 780 SSR-containing ESTs, a total of 290 primer pairs were successfully designed and used for validation of the amplification and assessment of the polymorphism among 22 genotypes of cultivated peanuts and 16 accessions of wild species. The results showed that 251 primer pairs yielded amplification products, of which 26 and 221 primer pairs exhibited polymorphism among the cultivated and wild species examined, respectively. Two to four alleles were found in cultivated peanuts, while 3–8 alleles presented in wild species. The apparent broad polymorphism was further confirmed by cloning and sequencing of amplified alleles. Sequence analysis of selected amplified alleles revealed that allelic diversity could be attributed mainly to differences in repeat type and length in the microsatellite regions. In addition, a few single base mutations were observed in the microsatellite flanking regions. Conclusion This study gives an insight into the frequency, type and distribution of peanut EST-SSRs and demonstrates successful development of EST-SSR markers in cultivated peanut. These EST-SSR markers could enrich the current resource of molecular markers for the peanut community and would be useful for qualitative and quantitative trait mapping, marker-assisted selection, and genetic diversity studies in cultivated peanut as well as related Arachis species. All of the 251 working primer pairs with names, motifs, repeat types, primer sequences, and alleles tested in cultivated and wild species are listed in Additional File 1. PMID:19309524

  5. Direct versus indirect actions of ghrelin on hypothalamic NPY neurons.

    PubMed

    Hashiguchi, Hiroshi; Sheng, Zhenyu; Routh, Vanessa; Gerzanich, Volodymyr; Simard, J Marc; Bryan, Joseph

    2017-01-01

    Assess direct versus indirect action(s) of ghrelin on hypothalamic NPY neurons. Electrophysiology was used to measure ion channel activity in NPY-GFP neurons in slice preparations. Ca2+ imaging was used to monitor ghrelin activation of isolated NPY GFP-labeled neurons. Immunohistochemistry was used to localize Trpm4, SUR1 and Kir6.2 in the hypothalamus. Acylated ghrelin depolarized the membrane potential (MP) of NPY-GFP neurons in brain slices. Depolarization resulted from a decreased input resistance (IR) in ~70% of neurons (15/22) or an increased IR in the remainder (7/22), consistent with the opening or closing of ion channels, respectively. Although tetrodotoxin (TTX) blockade of presynaptic action potentials reduced ghrelin-induced changes in MP and IR, ghrelin still significantly depolarized the MP and decreased IR in TTX-treated neurons, suggesting that ghrelin directly opens cation channel(s) in NPY neurons. In isolated NPY-GFP neurons, ghrelin produced a sustained rise of [Ca2+]c, with an EC50 ~110 pM. Pharmacologic studies confirmed that the direct action of ghrelin was through occupation of the growth hormone secretagogue receptor, GHS-R, and demonstrated the importance of the adenylate cyclase/cAMP/protein kinase A (PKA) and phospholipase C/inositol triphosphate (PLC/IP3) pathways as activators of 5' AMP-activated protein kinase (AMPK). Activation of isolated neurons was not affected by CNQX or TTX, but reducing [Na+]o suppressed activation, suggesting a role for Na+-permeable cation channels. SUR1 and two channel partners, Kir6.2 and Trpm4, were identified immunologically in NPY-GFP neurons in situ. The actions of SUR1 and Trpm4 modulators were informative: like ghrelin, diazoxide, a SUR1 agonist, elevated [Ca2+]c and glibenclamide, a SUR1 antagonist, partially suppressed ghrelin action, while 9-phenanthrol and flufenamic acid, selective Trpm4 antagonists, blocked ghrelin actions on isolated neurons. Ghrelin activation was unaffected by nifedipine and ω-conotoxin, inhibitors of L- and N-type Ca2+ channels, respectively, while Ni2+, mibefradil, and TTA-P2 completely or partially inhibited ghrelin action, implicating T-type Ca2+ channels. Activation was also sensitive to a spider toxin, SNX-482, at concentrations selective for R-type Ca2+ channels. Nanomolar concentrations of GABA markedly inhibited ghrelin-activation of isolated NPY-GFP neurons, consistent with chronic suppression of ghrelin action in vivo. NPY neurons express all the molecular machinery needed to respond directly to ghrelin. Consistent with recent studies, ghrelin stimulates presynaptic inputs that activate NPY-GFP neurons in situ. Ghrelin can also directly activate a depolarizing conductance. Results with isolated NPY-GFP neurons suggest the ghrelin-activated, depolarizing current is a Na+ conductance with the pharmacologic properties of SUR1/Trpm4 non-selective cation channels. In the isolated neuron model, the opening of SUR1/Trpm4 channels activates T- and SNX482-sensitive R-type voltage dependent Ca2+ channels, which could contribute to NPY neuronal activity in situ.

  6. Virtual Reality as a Medium for Sensorimotor Adaptation Training and Spaceflight Countermeasures

    NASA Technical Reports Server (NTRS)

    Madansingh, S.; Bloomberg, J. J.

    2014-01-01

    Astronauts experience a profound sensorimotor adaptation during transition to and from the microgravity environment of space. With the upcoming shift to extra-long duration missions (upwards of 1 year) aboard the International Space Station, the immediate risks to astronauts during these transitory periods become more important than ever to understand and prepare for. Recent advances in virtual reality technology enable everyday adoption of these tools for entertainment and use in training. Embedding an individual in a virtual environment (VE) allows the ability to change the perception of visual flow, elicit automatic motor behavior and produce sensorimotor adaptation, not unlike those required during long duration microgravity exposure. The overall goal of this study is to determine the feasibility of present head mounted display technology (HMD) to produce reliable visual flow information and the expected adaptation associated with virtual environment manipulation to be used in future sensorimotor adaptability countermeasures. To further understand the influence of visual flow on gait adaptation during treadmill walking, a series of discordant visual flow manipulations in a virtual environment are proposed. Six healthy participants (3 male and 3 female) will observe visual flow information via HMD (Oculus Rift DK2) while walking on an instrumented treadmill at their preferred walking speed. Participants will be immersed in a series of VE's resembling infinite hallways with different visual characteristics: an office hallway, a hallway with pillars and the hallway of a fictional spacecraft. Participants will perform three trials of 10 min. each, which include walking on the treadmill while receiving congruent or incongruent visual information via the HMD. In the first trial, participants will experience congruent visual information (baseline) where the hallway is perceived to move at the same rate as their walking speed. The final two trials will be randomized among participants where the hallway is perceived to move at either half (0.5x) or twice (2.0x) their preferred walking speed. Participants will remain on the treadmill between trials and will not be warned of the upcoming change to visual flow to minimize preparatory adjustments. Stride length, step frequency and dual-support time will be quantified during each trial. We hypothesize that participants will experience a rapid modification in gait performance during periods of adaptive change, expressed as a decrease in step length, an increase in step frequency and an increase in dual-support time, followed by a period of adaptation where these movement parameters will return to near-baseline levels. As stride length, step frequency and dual support times return to baseline values, an adaptation time constant will be derived to establish individual time-to-adapt (TTA). HMD technology represents a paradigm shift in sensorimotor adaptation training where gait adaptability can be stressed using off-the-shelf consumer products and minimal experimental equipment, allowing for greater training flexibility in astronaut and terrestrial applications alike.

  7. Direct versus indirect actions of ghrelin on hypothalamic NPY neurons

    PubMed Central

    Sheng, Zhenyu; Routh, Vanessa; Gerzanich, Volodymyr; Simard, J. Marc; Bryan, Joseph

    2017-01-01

    Objectives Assess direct versus indirect action(s) of ghrelin on hypothalamic NPY neurons. Materials and methods Electrophysiology was used to measure ion channel activity in NPY-GFP neurons in slice preparations. Ca2+ imaging was used to monitor ghrelin activation of isolated NPY GFP-labeled neurons. Immunohistochemistry was used to localize Trpm4, SUR1 and Kir6.2 in the hypothalamus. Results Acylated ghrelin depolarized the membrane potential (MP) of NPY-GFP neurons in brain slices. Depolarization resulted from a decreased input resistance (IR) in ~70% of neurons (15/22) or an increased IR in the remainder (7/22), consistent with the opening or closing of ion channels, respectively. Although tetrodotoxin (TTX) blockade of presynaptic action potentials reduced ghrelin-induced changes in MP and IR, ghrelin still significantly depolarized the MP and decreased IR in TTX-treated neurons, suggesting that ghrelin directly opens cation channel(s) in NPY neurons. In isolated NPY-GFP neurons, ghrelin produced a sustained rise of [Ca2+]c, with an EC50 ~110 pM. Pharmacologic studies confirmed that the direct action of ghrelin was through occupation of the growth hormone secretagogue receptor, GHS-R, and demonstrated the importance of the adenylate cyclase/cAMP/protein kinase A (PKA) and phospholipase C/inositol triphosphate (PLC/IP3) pathways as activators of 5' AMP-activated protein kinase (AMPK). Activation of isolated neurons was not affected by CNQX or TTX, but reducing [Na+]o suppressed activation, suggesting a role for Na+-permeable cation channels. SUR1 and two channel partners, Kir6.2 and Trpm4, were identified immunologically in NPY-GFP neurons in situ. The actions of SUR1 and Trpm4 modulators were informative: like ghrelin, diazoxide, a SUR1 agonist, elevated [Ca2+]c and glibenclamide, a SUR1 antagonist, partially suppressed ghrelin action, while 9-phenanthrol and flufenamic acid, selective Trpm4 antagonists, blocked ghrelin actions on isolated neurons. Ghrelin activation was unaffected by nifedipine and ω-conotoxin, inhibitors of L- and N-type Ca2+ channels, respectively, while Ni2+, mibefradil, and TTA-P2 completely or partially inhibited ghrelin action, implicating T-type Ca2+ channels. Activation was also sensitive to a spider toxin, SNX-482, at concentrations selective for R-type Ca2+ channels. Nanomolar concentrations of GABA markedly inhibited ghrelin-activation of isolated NPY-GFP neurons, consistent with chronic suppression of ghrelin action in vivo. Conclusions NPY neurons express all the molecular machinery needed to respond directly to ghrelin. Consistent with recent studies, ghrelin stimulates presynaptic inputs that activate NPY-GFP neurons in situ. Ghrelin can also directly activate a depolarizing conductance. Results with isolated NPY-GFP neurons suggest the ghrelin-activated, depolarizing current is a Na+ conductance with the pharmacologic properties of SUR1/Trpm4 non-selective cation channels. In the isolated neuron model, the opening of SUR1/Trpm4 channels activates T- and SNX482-sensitive R-type voltage dependent Ca2+ channels, which could contribute to NPY neuronal activity in situ. PMID:28877214

  8. Synthesis, Characterization, and Properties of the Two-Dimensional Chalcogenides: Monolayers, Alloys, and Heterostructures

    NASA Astrophysics Data System (ADS)

    Cain, Jeffrey D.

    Inspired by the triumphs of graphene, and motivated by its limitations, the science and engineering community is rapidly exploring the landscape of other layered materials in their atomically-thin forms. Dominating this landscape are the layered chalcogenides; diverse in chemistry, crystal structure, and properties, there are well over 100 primary members of this material family. Driven by quantum confinement, single layers (or few, in some cases) of these materials exhibit electronic, optical, and mechanical properties that diverge dramatically from their bulk counterparts. While initially isolated in monolayer form via mechanical exfoliation, the field of two-dimensional (2D) materials is being forced evolve to more scalable and reliable methods. Focusing on the chalcogenides (e.g. MoS2, Bi 2Se3, etc.), this dissertation introduces and mechanistically examines multiple novel synthetic approaches for the direct growth of monolayers, heterostructures, and alloys with the desired quality, reproducibility and generality. The first methods described in this thesis are physical vapor transport (PVT) and evaporative thinning (ET): a facile, top-down synthesis approach for creating ultrathin specimens of layered materials down to the two-dimensional limit. Evaporative thinning, applied in this study to the fabrication of A2X3 (Bi2Se3 and Sb2Te3) monolayers, is based on the controlled evaporation of material from initially thick specimens until the 2D limit is reached. The resultant flakes are characterized with a suite of imaging and spectroscopic techniques and the mechanism of ET is investigated via in-situ heating within a transmission electron microscope. Additionally, the basic transport properties of the resultant flakes are probed. The growth of ultrathin GeSe flakes is explored using PVT and the material's basic structure, properties, and stability are addressed. Second, oxide precursor based chemical vapor deposition (CVD) is presented for the direct growth of monolayer transition metal dichalcogenides materials (TMDs), MX2. Specifically, synthetic protocols for monolayers of the semiconducting TMDs, MoS2, WS2, and MoSe2, are presented and the layers are completely characterized with a full suite of techniques including scanning/transmission electron microscopy, scanning probe microscopy, and photo-spectroscopy (photoluminescence, Raman scattering) among others. Furthermore, the nucleation and growth processes in CVD grown TMD monolayers is investigated using aberration-corrected scanning transmission electron microscopy and a step-by-step nucleation and growth mechanism for monolayer TMDs is elucidated. Third, the use of monolayers as building blocks for more complex structures is explored and a predictive approach for the synthesis of van der Waals heterostructures and monolayer alloys is designed. This is accomplished using an intellectual framework analogous to the Time-Temperature-Transformation (TTT) diagrams that are ubiquitous in traditional materials science and metallurgy. These are called Time-Temperature-Architecture (TTA) diagrams, wherein the term "architecture" defines the specific conformation of the 2D components. These diagrams provide process guidance to synthesize a library of heterostructures with a range of morphologies and monolayer alloys within both the transition metal sulfide and selenide systems. Lastly, some next steps for future research are outlined. An appendix of summaries of collaborative studies of the optical and electronic properties of CVD grown monolayers TMDs is appended.

  9. Use of Treated Municipal Wastewater as Power Plant Cooling System Makeup Water: Tertiary Treatment versus Expanded Chemical Regimen for Recirculating Water Quality Management

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    David Dzombak; Radisav Vidic; Amy Landis

    Treated municipal wastewater is a common, widely available alternative source of cooling water for thermoelectric power plants across the U.S. However, the biodegradable organic matter, ammonia-nitrogen, carbonate and phosphates in the treated wastewater pose challenges with respect to enhanced biofouling, corrosion, and scaling, respectively. The overall objective of this study was to evaluate the benefits and life cycle costs of implementing tertiary treatment of secondary treated municipal wastewater prior to use in recirculating cooling systems. The study comprised bench- and pilot-scale experimental studies with three different tertiary treated municipal wastewaters, and life cycle costing and environmental analyses of various tertiarymore » treatment schemes. Sustainability factors and metrics for reuse of treated wastewater in power plant cooling systems were also evaluated. The three tertiary treated wastewaters studied were: secondary treated municipal wastewater subjected to acid addition for pH control (MWW_pH); secondary treated municipal wastewater subjected to nitrification and sand filtration (MWW_NF); and secondary treated municipal wastewater subjected nitrification, sand filtration, and GAC adsorption (MWW_NFG). Tertiary treatment was determined to be essential to achieve appropriate corrosion, scaling, and biofouling control for use of secondary treated municipal wastewater in power plant cooling systems. The ability to control scaling, in particular, was found to be significantly enhanced with tertiary treated wastewater compared to secondary treated wastewater. MWW_pH treated water (adjustment to pH 7.8) was effective in reducing scale formation, but increased corrosion and the amount of biocide required to achieve appropriate biofouling control. Corrosion could be adequately controlled with tolytriazole addition (4-5 ppm TTA), however, which was the case for all of the tertiary treated waters. For MWW_NF treated water, the removal of ammonia by nitrification helped to reduce the corrosivity and biocide demand. Also, the lower pH and alkalinity resulting from nitrification reduced the scaling to an acceptable level, without the addition of anti-scalant chemicals. Additional GAC adsorption treatment, MWW_NFG, yielded no net benefit. Removal of organic matter resulted in pitting corrosion in copper and cupronickel alloys. Negligible improvement was observed in scaling control and biofouling control. For all of the tertiary treatments, biofouling control was achievable, and most effectively with pre-formed monochloramine (2-3 ppm) in comparison with NaOCl and ClO2. Life cycle cost (LCC) analyses were performed for the tertiary treatment systems studied experimentally and for several other treatment options. A public domain conceptual costing tool (LC3 model) was developed for this purpose. MWW_SF (lime softening and sand filtration) and MWW_NF were the most cost-effective treatment options among the tertiary treatment alternatives considered because of the higher effluent quality with moderate infrastructure costs and the relatively low doses of conditioning chemicals required. Life cycle inventory (LCI) analysis along with integration of external costs of emissions with direct costs was performed to evaluate relative emissions to the environment and external costs associated with construction and operation of tertiary treatment alternatives. Integrated LCI and LCC analysis indicated that three-tiered treatment alternatives such as MWW_NSF and MWW_NFG, with regular chemical addition for treatment and conditioning and/or regeneration, tend to increase the impact costs and in turn the overall costs of tertiary treatment. River water supply and MWW_F alternatives with a single step of tertiary treatment were associated with lower impact costs, but the contribution of impact costs to overall annual costs was higher than all other treatment alternatives. MWW_NF and MWW_SF alternatives exhibited moderate external impact costs with moderate infrastructure and chemical conditioner dosing, which makes them (especially MWW_NF) better treatment alternatives from the environmental sustainability perspective since they exhibited minimal contribution to environmental damage from emissions.« less

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