Shewanella oneidensis cytochrome c nitrite reductase (ccNiR) does not disproportionate hydroxylamine to ammonia and nitrite, despite a strongly favorable driving force.

PubMed

Youngblut, Matthew; Pauly, Daniel J; Stein, Natalia; Walters, Daniel; Conrad, John A; Moran, Graham R; Bennett, Brian; Pacheco, A Andrew

2014-04-08

Cytochrome c nitrite reductase (ccNiR) from Shewanella oneidensis, which catalyzes the six-electron reduction of nitrite to ammonia in vivo, was shown to oxidize hydroxylamine in the presence of large quantities of this substrate, yielding nitrite as the sole free nitrogenous product. UV-visible stopped-flow and rapid-freeze-quench electron paramagnetic resonance data, along with product analysis, showed that the equilibrium between hydroxylamine and nitrite is fairly rapidly established in the presence of high initial concentrations of hydroxylamine, despite said equilibrium lying far to the left. By contrast, reduction of hydroxylamine to ammonia did not occur, even though disproportionation of hydroxylamine to yield both nitrite and ammonia is strongly thermodynamically favored. This suggests a kinetic barrier to the ccNiR-catalyzed reduction of hydroxylamine to ammonia. A mechanism for hydroxylamine reduction is proposed in which the hydroxide group is first protonated and released as water, leaving what is formally an NH2(+) moiety bound at the heme active site. This species could be a metastable intermediate or a transition state but in either case would exist only if it were stabilized by the donation of electrons from the ccNiR heme pool into the empty nitrogen p orbital. In this scenario, ccNiR does not catalyze disproportionation because the electron-donating hydroxylamine does not poise the enzyme at a sufficiently low potential to stabilize the putative dehydrated hydroxylamine; presumably, a stronger reductant is required for this.

A theoretical study of structural, opto-electronic and nonlinear properties of arylboroxine derivatives

NASA Astrophysics Data System (ADS)

Islam, Nasarul; Pandith, Altaf Hussain

2018-01-01

Density functional theory at CAM-B3LYP/6-311G++ (2d, 2p) level was employed to study the Triphenylboroxine derivatives ( TB) containing electron donating and electron substituents, for their charge transfer and nonlinear optical properties. The results reveal that electron donating groups facilitate the rapid electron injection as compared to unsubstituted TB. It was observed that upon substitution with electron donating groups, the TB derivatives show an increased double bond character in the B3-C18 bond indicating an increase in the degree of conjugation. The Frontier molecular orbital studies indicate that highest occupied molecular orbitals of the neutral molecules delocalize primarily over the three phenyl rings and bridging oxygen atoms, whereas the lowest unoccupied molecular orbitals localize largely on the two phenyl rings and the boron atoms. Further, the TD-DFT studies indicate that the maximum absorption band results from the electron transitions from the initial states that are contributed by the HOMO and HOMO-1 to the final states that are mainly contributed by the LUMOs. In addition, we have observed that the introduction of electron donating group to the TB-7 leads to more active nonlinear performance.

Stimulus for organ donation: a survey of the American Society of Transplant Surgeons membership.

PubMed

Rodrigue, J R; Crist, K; Roberts, J P; Freeman, R B; Merion, R M; Reed, A I

2009-09-01

Federal legislation has been proposed to modify the National Organ Transplant Act in a way that would permit government-regulated strategies, including financial incentives, to be implemented and evaluated. The Council and Ethics Committee of the American Society of Transplant Surgeons conducted a brief web-based survey of its members' (n = 449, 41.6% response rate) views on acceptable or unacceptable strategies to increase organ donation. The majority of the membership supports reimbursement for funeral expenses, an income tax credit on the final return of a deceased donor and an income tax credit for registering as an organ donor as strategies for increasing deceased donation. Payment for lost wages, guaranteed health insurance and an income tax credit are strategies most strongly supported by the membership to increase living donation. For both deceased and living donation, the membership is mostly opposed to cash payments to donors, their estates or to next-of-kin. There is strong support for a government-regulated trial to evaluate the potential benefits and harms of financial incentives for both deceased and living donation. Overall, there is strong support within the ASTS membership for changes to NOTA that would permit the implementation and careful evaluation of indirect, government-regulated strategies to increase organ donation.

Survey of pediatricians' opinions on donation after cardiac death: are the donors dead?

PubMed

Joffe, Ari R; Anton, Natalie R; deCaen, Allan R

2008-11-01

There has been debate in the ethics literature as to whether the donation-after-cardiac-death donor is dead after 5 minutes of absent circulation. We set out to determine whether pediatricians consider the donation-after-cardiac-death donor as dead. A survey was mailed to all 147 pediatricians who are affiliated with the university teaching children's hospital. The survey had 4 pediatric patient scenarios in which a decision was made to donate organs after 5 minutes of absent circulation. Background information described the organ shortage, and the debate about the term "irreversibility" applied to death in donation after cardiac death. Descriptive statistics were used, with responses between groups compared by using the chi(2) statistic. The response rate was 54% (80 of 147). In each scenario, when given a patient described as dead with absent circulation for 5 minutes,

Squaraine dyes as efficient coupling bridges between triarylamine redox centres.

PubMed

Völker, Sebastian F; Renz, Manuel; Kaupp, Martin; Lambert, Christoph

2011-12-09

Various indolenine squarylium dyes with additional electron-donating amine redox centres have been synthesised and their redox chemistry has been studied. A combination of cyclic voltammetry, spectro-electrochemistry and DFT calculations has been used to characterise the electronic structure of the mono-, di- and, in one case, trications. All monocations still retain the cyanine-like, delocalised character due to the relatively low redox potential of the squaraine bridge and are therefore compounds of Robin-Day class III. Thus we extended previous studies on organic mixed-valence systems by using the indolenine squaraine moiety as very electron-rich bridge between two electron-donating amine redox centres to provoke a strong coupling between the additional redox centres. We synthesised TA3, which has an N-N distance of 26 bonds between the triarylamine redox centres and is to our knowledge the longest bis(triarylamine) radical cation that is completely delocalised. We furthermore show that altering the symmetry of a squaraine dye by substitution of a squaric ring oxygen atom by a dicyanomethylene group has a direct impact on the optical properties of the monocations. In case of the dications, it turned out that the energetically most stable state of dianisylamine-substituted squaraines is an anti-ferromagnetically coupled open-shell singlet state. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Roles of conjugated double bonds in electron-donating capacity of sorghum grains

USDA-ARS?s Scientific Manuscript database

Electron-donating and metal ion complexation ability of tannins play key roles as antioxidants and in mold/bird resistance. In this study, rapid, sensitive, and nondestructive fluorescence excitation-emission (EEM) spectrophotometry was utilized to correlate structural attributes of sorghum tannins...

Aromatic hydroxylation by cytochrome P450: model calculations of mechanism and substituent effects.

PubMed

Bathelt, Christine M; Ridder, Lars; Mulholland, Adrian J; Harvey, Jeremy N

2003-12-10

The mechanism and selectivity of aromatic hydroxylation by cytochrome P450 enzymes is explored using new B3LYP density functional theory computations. The calculations, using a realistic porphyrin model system, show that rate-determining addition of compound I to an aromatic carbon atom proceeds via a transition state with partial radical and cationic character. Reactivity is shown to depend strongly on ring substituents, with both electron-withdrawing and -donating groups strongly decreasing the addition barrier in the para position, and it is shown that the calculated barrier heights can be reproduced by a new dual-parameter equation based on radical and cationic Hammett sigma parameters.

Understanding the pros and cons of organ donation decision-making: Decisional balance and expressing donation intentions among African Americans.

PubMed

Flemming, Shauna St Clair; Redmond, Nakeva; Williamson, Dana Hz; Thompson, Nancy J; Perryman, Jennie P; Patzer, Rachel E; Arriola, Kimberly Jacob

2018-04-01

Increasing public commitment to organ donation is critical to improving donor kidney availability for end-stage renal disease patients desiring transplant. This study surveyed ( N = 1339) African Americans, measuring perceived pros relative to cons of organ donation, to evaluate an existing Transtheoretical Model decisional balance scale and associations between decisional balance and expressing donation intentions. Findings supported the existing scale structure. More positive decisional balance ratios were associated with 1.76 times the odds of expressing intentions (95% confidence interval = 1.52-2.04). Pros were more strongly linked to donation intentions than cons. Greater understanding of organ donation decision-making is valuable for informing interventions that encourage donation.

Geometry dependence of electron donating or accepting abilities of amine groups in 4,4‧-disulfanediylbis(methylene)dithiazol-2-amine: Pyramidal versus planar

NASA Astrophysics Data System (ADS)

Karabıyık, Hasan; Kırılmış, Cumhur; Karabıyık, Hande

2017-08-01

The molecular and crystal structure of the title compound in which two thiazole-2-amine rings are linked to each other by disulfide bridge (sbnd Csbnd Ssbnd Ssbnd Csbnd) were studied by single-crystal X-ray diffraction, FT-IR, NMR spectroscopy, quantum chemical calculations and topological analyses on the electron density. A novel synthesis route for the compounds having symmetrical disulfide bridge is reported. The most important result regarding the compound is about electron donating or accepting properties of the terminal amine groups. Planar amine group acts as an electron-donating group, while pyramidal amine behaves as electron-accepting group. This inference was confirmed by scrutiny of crystallographic geometry and quantum chemical studies. To ascertain underlying reasons for this fact, intermolecular interactions (Nsbnd H⋯N type H-bonds and Csbnd H···π interactions) were studied. These interactions involving aromatic thiazole rings are verified by topological electron density and Hirshfeld surface analyses. Intermolecular interactions do not have an effect on the differentiation in electron donating or accepting ability of amine groups, because both amine groups are involved in Nsbnd H⋯N type H-bonds. In methodological sense, it has been understood that Ehrenfest forces acting on electron density are useful theoretical probe to analyze intra-molecular charge transfer processes.

Donors' blood group declaration before donation can be used as a tool for electronic crossmatching.

PubMed

Arslan, O

2005-12-01

Electronic crossmatching (E-XM) is used to detect ABO incompatibility. In developing countries, as many of the donations are from first-time donors, it is difficult to guarantee the accuracy of the ABO/Rh label on these units to use them for E-XM. This problem was overcome with a new software 'hemosoft', using donors' blood group declaration before donation as a tool for E-XM. During registration, donors either declare their blood group or give no comment. For, ABO/Rh grouping, either two results from different donations or only one in concordant with the declaration before donation is needed. If there is a conflict, second typing is performed from the unit segment. If donors give no declaration, two different technicians perform typing, one from the sample tube and the other from the unit segment. Of 18,618 donations performed, 640 (3%) were repeated and the rest were first-time donations. In 16,327, typing was performed once, as the blood group declaration and the typing results were identical. In 2407, grouping was performed twice, as donors gave no declaration or conflicts between declaration and typing results were found. No labelling or wrong unit-release errors were detected in units donated, typed and labelled in our centre. In 26,402 donations, 16,314 (61.8%) E-XMs were performed. No major haemolytic transfusion reaction was recorded. Donors' ABO/Rh declaration before donation can be used as a tool for E-XM, instead of the requirement for serological confirmation or a second donation to guarantee grouping.

Electron transfer capacity dependence of quinone-mediated Fe(III) reduction and current generation by Klebsiella pneumoniae L17.

PubMed

Li, Xiaomin; Liu, Liang; Liu, Tongxu; Yuan, Tian; Zhang, Wei; Li, Fangbai; Zhou, Shungui; Li, Yongtao

2013-06-01

Quinone groups in exogenous electron shuttles can accelerate extracellular electron transfer (EET) from bacteria to insoluble terminal electron acceptors, such as Fe(III) oxides and electrodes, which are important in biogeochemical redox processes and microbial electricity generation. However, the relationship between quinone-mediated EET performance and electron-shuttling properties of the quinones remains incompletely characterized. This study investigates the effects of a series of synthetic quinones (SQs) on goethite reduction and current generation by a fermenting bacterium Klebsiella pneumoniae L17. In addition, the voltammetric behavior and electron transfer capacities (ETCs) of SQ, including electron accepting (EAC) and donating (EDC) capacities, is also examined using electrochemical methods. The results showed that SQ can significantly increase both the Fe(III) reduction rates and current outputs of L17. Each tested SQ reversibly accepted and donated electrons as indicated by the cyclic voltammograms. The EAC and EDC results showed that Carmine and Alizarin had low relative capacities of electron transfer, whereas 9,10-anthraquinone-2,6-disulfonic acid (AQDS), 2-hydroxy-1,4-naphthoquinone (2-HNQ), and 5-hydroxy-1,4-naphthoquinone (5-HNQ) showed stronger relative ETC, and 9,10-anthraquinone-2-carboxylic acid (AQC) and 9,10-anthraquinone-2-sulfonic acid (AQS) had high relative ETC. Enhancement of microbial goethite reduction kinetics and current outputs by SQ had a good linear relationship with their ETC, indicating that the effectiveness of quinone-mediated EET may be strongly dependent on the ETC of the quinones. Therefore, the presence of quinone compounds and fermenting microorganisms may increase the diversity of microbial populations that contribute to element transformation in natural environments. Moreover, ETC determination of different SQ would help to evaluate their performance for microbial EET under anoxic conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.

Elucidating the Structure-Reactivity Correlations of Phenothiazine-Based Fluorescent Probes toward ClO.

PubMed

Wang, Shichao; Zhang, Boyu; Wang, Wenjing; Feng, Gang; Yuan, Daqiang; Zhang, Xuanjun

2018-06-07

In this work, with the aim of developing effective molecular probes and investigating the structure-reactivity correlation, a short series of phenothiazine-based fluorescent probes are designed for the detection of ClO - with differing electron push-pull groups. Sensing experiment results and single-crystal X-ray analysis with the aid of time-dependent DFT (TD-DFT) calculations reveal that substituting groups with increasing electron-withdrawing ability can increase the dihedral angle of the phenothiazine moiety and reduce the gap energy of the probes, leading to enhanced reactivity toward ClO - . Both PT1 and PT2 show two-color switching upon detection of ClO - . PT1, with the strong electron-donating group thiophene, shows a fluorescence color switch from salmon to blue. PT2, with a medium electron-donating/accepting group benzothiazole, shows a fluorescence color switch from red to green. However, both PT1 and PT2 show almost no response to ONOO - . Through the introduction of strong electron-withdrawing ketone combined with a cyano group, PT3 shows a cyan emission upon detection of ClO - and weak red emission upon detection of ONOO - . HRMS and 1 H NMR results confirm that PT1 and PT2 have the same sensing mode, in which the divalent sulfur of phenothiazine can be oxidized to sulfoxide by ClO - . Upon reaction with ClO - , PT3 experiences two-step reactions. It is first oxidized into the sulfone structure by ClO - , and then transformed into sulfoxide phenothiazine aldehyde. Upon encountering ONOO - , PT3 changes into an aldehyde structure and some nonfluorescent byproducts. Owing to their special selectivity and high sensitivity, PT1 and PT2 are applied to image the endogenous ClO - in macrophage cells and zebrafish larvae. This study is expected to provide useful guidelines for probe design for various applications. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Photoinduced Bimolecular Electron Transfer from Cyano Anions in Ionic Liquids

DOE PAGES

Wu, Boning; Liang, Min; Maroncelli, Mark; ...

2015-10-26

Ionic liquids with electron-donating anions are used to investigate rates and mechanisms of photoinduced bimolecular electron transfer to the photoexcited acceptor 9,10-dicyanoanthracene (9,10-DCNA). The set of five cyano anion ILs studied comprises the 1-ethyl-3-methylimidazolium cation paired with each of these five anions: selenocyanate, thiocyanate, dicyanamide, tricyanomethanide, and tetracyano-borate. Measurements with these anions dilute in acetonitrile and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)-amide show that the selenocyanate and tricyanomethanide anions are strong quenchers of the 9,10-DCNA fluorescence, thiocyanate is a moderately strong quencher, dicyanamide is a weak quencher, and no quenching is observed for tetracyanoborate. Quenching rates are obtained from both time-resolved fluorescence transients andmore » time-integrated spectra. Finally, application of a Smoluchowski diffusion-and-reaction model showed that the complex kinetics observed can be fit using only two adjustable parameters, D and V 0, where D is the relative diffusion coefficient between donor and acceptor and V 0 is the value of the electronic coupling at donor-acceptor contact.« less

A Luminescent Zinc(II) Metal-Organic Framework (MOF) with Conjugated π-Electron Ligand for High Iodine Capture and Nitro-Explosive Detection.

PubMed

Yao, Ru-Xin; Cui, Xin; Jia, Xiao-Xia; Zhang, Fu-Qiang; Zhang, Xian-Ming

2016-09-19

A porous luminescent zinc(II) metal-organic framework (MOF) with a NbO net [Zn2(tptc)(apy)2-x(H2O)x]·H2O (1) (where x ≈ 1, apy = aminopyridine, H4tptc = terphenyl-3,3″,5,5″-tetracarboxylic acid), constructed using paddlewheel [Zn2(COO)4] clusters and π-electron-rich terphenyl-tetracarboxylic acid, has been solvothermally synthesized and characterized. Interestingly, the material displays efficient, reversible adsorption of radioactive I2 in vapor and in solution (up to 216 wt %). The strong affinity for I2 is mainly due to it having large porosity, a conjugated π-electron aromatic system, halogen bonds, and electron-donating aminos. Furthermore, luminescent study indicated that 1 exhibits high sensitivity to electron-deficient nitrobenzene explosives via fluorescence quenching.

Determinants of plasma donation: A review of the literature.

PubMed

Beurel, A; Terrade, F; Lebaudy, J-P; Danic, B

2017-09-01

The major contribution of Human Sciences in the understanding of the whole blood donation behavior has been through the study of individuals' motivations and deterrents to donate. However, if whole blood donation has been very widely studied in the last sixty years, we still know very little about plasma donation in voluntary non-remunerated environments. Yet, the need for plasma-derived products has been strongly increasing for some years, and blood collection agencies have to adapt if they want to meet this demand. This article aims to review the main motivations and deterrents to whole blood donation, and to compare them with those that we already know concerning plasma donation. Current evidence shows similarities between both behaviors, but also differences that indicate a need for further research regarding plasma donation. Copyright © 2017. Published by Elsevier SAS.

Taming interfacial electronic properties of platinum nanoparticles on vacancy-abundant boron nitride nanosheets for enhanced catalysis

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

Zhu, Wenshuai; Wu, Zili; Foo, Guo Shiou

Taming interfacial electronic effects on Pt nanoparticles modulated by their concomitants has emerged as an intriguing approach to optimize Pt catalytic performance. Here, we report Pt nanoparticles assembled on vacancy-abundant hexagonal boron nitride nanosheets and their use as a model catalyst to embrace an interfacial electronic effect on Pt induced by the nanosheets with N-vacancies and B-vacancies for superior CO oxidation catalysis. Experimental results indicate that strong interaction exists between Pt and the vacancies. Bader charge analysis shows that with Pt on B-vacancies, the nanosheets serve as a Lewis acid to accept electrons from Pt, and on the contrary, whenmore » Pt sits on N-vacancies, the nanosheets act as a Lewis base for donating electrons to Pt. The overall-electronic effect demonstrates an electron-rich feature of Pt after assembling on hexagonal boron nitride nanosheets. Such an interfacial electronic effect makes Pt favour the adsorption of O 2, alleviating CO poisoning and promoting the catalysis.« less

Taming interfacial electronic properties of platinum nanoparticles on vacancy-abundant boron nitride nanosheets for enhanced catalysis

DOE PAGES

Zhu, Wenshuai; Wu, Zili; Foo, Guo Shiou; ...

2017-06-09

Taming interfacial electronic effects on Pt nanoparticles modulated by their concomitants has emerged as an intriguing approach to optimize Pt catalytic performance. Here, we report Pt nanoparticles assembled on vacancy-abundant hexagonal boron nitride nanosheets and their use as a model catalyst to embrace an interfacial electronic effect on Pt induced by the nanosheets with N-vacancies and B-vacancies for superior CO oxidation catalysis. Experimental results indicate that strong interaction exists between Pt and the vacancies. Bader charge analysis shows that with Pt on B-vacancies, the nanosheets serve as a Lewis acid to accept electrons from Pt, and on the contrary, whenmore » Pt sits on N-vacancies, the nanosheets act as a Lewis base for donating electrons to Pt. The overall-electronic effect demonstrates an electron-rich feature of Pt after assembling on hexagonal boron nitride nanosheets. Such an interfacial electronic effect makes Pt favour the adsorption of O 2, alleviating CO poisoning and promoting the catalysis.« less

Gifts of giving: the role of empathy and perceived benefits to others and self in young adults' decisions to become organ donors.

PubMed

Cohen, Elizabeth L; Hoffner, Cynthia

2013-01-01

Trait empathy and self-interest exert a strong influence on different prosocial behaviors, but their role in the promotion of organ donation registration is unclear. A survey examined how perceived benefits of organ donation for others and the self affect people's willingness to register as donors. Perceived other-benefits did not predict registration. Those with lower risk and greater self-benefit perceptions were more willing to donate. Empathic concern predicted donation willingness and moderated the effect of other-benefit perceptions, such that other-benefit perceptions predicted donation willingness among those with greater empathic concern. Applications of these findings to organ donation promotion are discussed.

A metal-organic framework based on nanosized hexagonal channels as fluorescent indicator for detection of nitroaromatic explosives

NASA Astrophysics Data System (ADS)

Hu, Xiao-Li; Wang, Xin-Long; Su, Zhong-Min

2018-02-01

A novel Zn-MOF (metal organic framework) [Zn3(NTB)2(DMA)2]·12DMA (NTB = 4,4‧,4″-nitrilotrisbenzoic acid; DMA = N,N-dimethylacetamide) (1) was obtained under solvothermal condition. The resulted MOF which is based on {Zn3} SBU displays an interesting (3,6)-connected three-dimensional net with nanosized, hexagonal channels. Additionally, 1 can be a useful fluorescent indicator for the detection of nitroaromatic explosives qualitatively and quantitatively via a strong quenching effect, especially for picric acid (PA). With increasing - NO2 groups, energy transfer from the electron-donating framework to high electron deficiency becomes more, making the effect of fluorescence quenching more obvious. The result demonstrates that the photo-induced electron transfer (PET) is responsible for the emission quenching.

On irreversible adsorption of electron-donating compounds in aqueous solution

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

Tamon, Hajime; Atsushi, Masanori; Okazaki, Morio

Activated carbons and synthetic adsorbents have been used for liquid purification and wastewater treatment. The feasibility of an adsorption process depends greatly on the cost of regeneration of spent adsorbents. If irreversible adsorption occurs, regeneration of spent adsorbent is very difficult. Hence, it is very important to understand why irreversible adsorption appears in aqueous solution. In the adsorption of electron-donating compounds such as phenol, aniline, L-phenylalanine, and L-tyrosine from aqueous solution, irreversibility was observed on activated carbon and graphite. The compounds, except L-tyrosine, were reversibly adsorbed on a synthetic adsorbent. In the case where the carbonaceous adsorbents contacted the aqueousmore » solution containing electron-donating compounds for a long time, the irreversible amount adsorbed increased with the contact time. A two-state adsorption model was used to explain why the irreversible adsorption of electron-donating compound appears in aqueous solution. First, the compound is adsorbed in the precursor state for irreversible adsorption, and then moves into its irreversible state over a potential energy barrier after a long contact time. The appearance of irreversible adsorption was qualitatively explained by the two-state adsorption model.« less

The Blood Donation Ambivalence Survey: measuring conflicting attitudes about giving blood.

PubMed

Fox, K R; Himawan, L K; France, C R

2017-05-18

This study was designed to develop and conduct initial validation testing for a novel measure of ambivalence about donating blood. Previous studies of living organ, bone marrow and stem cell donors have identified donation-related ambivalence as a predictor of decisions about donation and post-donation outcomes. Ambivalence about blood donation has not received the same attention. In Study 1, a sample of young adults (N = 396) were administered test items of ambivalence, and exploratory (EFA) and confirmatory factor analyses (CFA) were performed to identify the Blood Donation Ambivalence Survey. In Study 2, a separate sample of young adults (N = 241) completed the Blood Donation Ambivalence Survey in addition to questionnaires assessing known predictors of blood donation. Exploratory and confirmatory factor analyses indicated a two-factor structure reflecting commitment to donating blood and indecision about giving blood. The commitment subscale was positively related to known predictors of increased donation behaviour (e.g. donation intention, self-efficacy), whereas the indecision subscale was positively related to known predictors of decreased donation behaviour (e.g. donation anxiety, negative affect). Furthermore, a history of blood donation was associated with greater commitment and less indecision. The present findings provide strong initial support for the reliability and validity of a novel measure of blood donor ambivalence. © 2017 British Blood Transfusion Society.

Theoretical study on the electronic structures and phosphorescent properties of four Ir(III) complexes with different substituents on the ancillary ligand

NASA Astrophysics Data System (ADS)

Han, Deming; Shang, Xiaohong; Zhang, Gang; Zhao, Lihui

2013-12-01

The geometry structures, electronic structures, absorption and phosphorescent properties of four Ir(III) complexes {[(F2-ppy)2Ir(pta-X)], where F2-ppy = (2,4-difluoro)phenylpyridine; pta = pyridine-1,2,4-triazole; X = -CF3; -H; -CH3; -N(CH3)2}, are investigated using the density functional method. The results reveal that the electron-accepting group -CF3 has no obvious effect on absorption and emission properties, while the substitutive group -N(CH3)2 with strong electron-donating ability has obvious effect on the emission properties. The mobility of hole and electron were studied computationally based on the Marcus-Hush theory. Calculations of ionisation potential and electron affinity were used to evaluate the injection abilities of holes and electrons into these complexes. We hope that this theoretical work can provide a suitable guide to the future design and synthesis of novel phosphorescent materials for use in the organic light-emitting diodes.

Knowledge, attitude and practices of people towards voluntary blood donation in Uttarakhand.

PubMed

Agrawal, Amit; Tiwari, Aseem K; Ahuja, Alok; Kalra, Rakesh

2013-01-01

Blood transfusions form a crucial and irreplaceable part in the medical management of many diseases. The collection of blood from voluntary, non-remunerated blood donors from low risk populations is an important measure for ensuring the availability and safety of blood transfusion. In a state like Uttarakhand which is visited by lakhs of visitors during pilgrimage season and where natural calamities and accidents are very common, the availability of blood is of utmost importance. To find out knowledge, attitude and practices of people towards voluntary blood donation to comprehend the situation and find ways to enhance voluntary blood donation in the state of Uttarakhand. Multi stage methodology was designed to target population including general population, influencers (doctors) and supporting organizations (camp organizers, State AIDS Control Society Officials) who were subjected to in-depth interview using pre-structured questionnaires to assess knowledge/awareness about voluntary blood donation, factors preventing and source of knowledge about voluntary blood donation. The sample population consisted of mostly men (67%) in the age-group of 26-35 years. Requirement of blood and the measures to promote voluntary blood donation have a direct relationship with the total population and literacy level of the population. Awareness about blood donation, source of knowledge about blood donation, reasons for not donating blood are particularly stressed. With increase in educational level, the awareness level was also found to increase. While among illiterates 81 percent of the respondents knew about blood donation, among the post graduates the same ratio was found to be almost cent-percent. Among various reasons cited for not donating blood, lack of awareness being the most common reason. People gathered information about blood donation from several different sources with electronic media being the most prominent. This study illustrates how increasing awareness and marketing 'Voluntary blood donation' can enhance adequacy of blood needs of a state or for that matter the entire country. This study also underlines how different media, especially electronic media, can be used to propagate altruistic blood donation.

An academic-based hospital donor site: do physicians donate blood?

PubMed

Kanner, William A; Jeffus, Susanne; Wehrli, Gay

2009-01-01

The objectives of this prospective, cross-sectional study were to characterize blood donors in an academic-based hospital donor center, to determine whether physicians donate, and to elucidate the donation impetus. A confidential survey was issued to presenting, potential donors over 200 weekdays. Three questions were asked: their role at the institution, if and when they had previously donated blood, and what prompted the current donation. The majority of the 687 respondents were institution-affiliated (73.5%) and 79.3% had previously donated, with a median of 3 mo since the prior donation. Only 21 (3.1%) respondents were physicians. The predominant reasons for donor presentation were an appointment, knowing it had been 8 wk since the last donation, and contact by the blood center to donate. This study shows the dearth of physician blood donors and a strong cohort of institution-affiliated repeat donors. Physicians represent a potential, stable, and sustainable donor pool; further studies are needed to establish physician recruitment programs.

Excitation and emission wavelength ratiometric cyanide-sensitive probes for physiological sensing.

PubMed

Badugu, Ramachandram; Lakowicz, Joseph R; Geddes, Chris D

2004-04-01

We characterize three new fluorescent probes that show both spectral shifts and intensity changes in the presence of aqueous cyanide, allowing for both excitation and fluorescence emission wavelength ratiometric and colorimetric sensing. The relatively high binding constants of the probes for cyanide enables a distinct colorimetric change to be visually observed with as little as 10 microM cyanide. The response of the new probes is based on the ability of the boronic acid group to interact with the CN(-) anion, changing from the neutral form of the boronic acid group R-B(OH)(2) to the anionic R-B(-)(OH)3 form, which is an electron-donating group. The presence of an electron-deficient quaternary heterocyclic nitrogen center and a strong electron-donating amino group in the 6 position on the quinolinium backbone provides for the spectral changes observed upon CN(-) complexation. We have determined the binding constants for the ortho-, meta-, and para-boronic acid probes to be 0.12, 0.17, and 0.14 microM(-3). In addition we have synthesized a control compound that does not contain the boronic acid moiety, allowing for structural comparisons and a rationale for the sensing mechanism to be made. Finally we show that the affinity for monosaccharides, such as glucose or fructose, is relatively low as compared to that for cyanide, enabling the potential detection of cyanide in physiologies up to lethal levels.

The Indian Ocean tsunami and private donations to NGOs.

PubMed

Kim, Youngwan; Nunnenkamp, Peter; Bagchi, Chandreyee

2016-10-01

Non-governmental organisations (NGOs) are widely believed to raise their flag in humanitarian hotspots with a strong media presence in order to attract higher private donations. We assess this hypothesis by comparing the changes in donations between US-based NGOs with and without aid operations in the four countries most affected by the tsunami in the Indian Ocean in 2004. Simple before-after comparisons tend to support the hypothesis that 'flying the flag' helps attract higher private donations. However, performing a difference-in-difference-in-differences (DDD) approach, we find only weak indications that private donors systematically and strongly preferred NGOs with operations in the region. Extended specifications of the baseline regressions reveal that our major findings are robust. NGO heterogeneity matters in some respects, but the DDD results hold when accounting for proxies of the NGOs' reputation and experience. © 2016 The Author(s). Disasters © Overseas Development Institute, 2016.

Knowledge, attitude and practices of people towards voluntary blood donation in Uttarakhand

PubMed Central

Agrawal, Amit; Tiwari, Aseem K.; Ahuja, Alok; Kalra, Rakesh

2013-01-01

Introduction: Blood transfusions form a crucial and irreplaceable part in the medical management of many diseases. The collection of blood from voluntary, non-remunerated blood donors from low risk populations is an important measure for ensuring the availability and safety of blood transfusion. In a state like Uttarakhand which is visited by lakhs of visitors during pilgrimage season and where natural calamities and accidents are very common, the availability of blood is of utmost importance. Aim: To find out knowledge, attitude and practices of people towards voluntary blood donation to comprehend the situation and find ways to enhance voluntary blood donation in the state of Uttarakhand. Materials and Methods: Multi stage methodology was designed to target population including general population, influencers (doctors) and supporting organizations (camp organizers, State AIDS Control Society Officials) who were subjected to in-depth interview using pre-structured questionnaires to assess knowledge/awareness about voluntary blood donation, factors preventing and source of knowledge about voluntary blood donation. Result: The sample population consisted of mostly men (67%) in the age-group of 26-35 years. Requirement of blood and the measures to promote voluntary blood donation have a direct relationship with the total population and literacy level of the population. Awareness about blood donation, source of knowledge about blood donation, reasons for not donating blood are particularly stressed. With increase in educational level, the awareness level was also found to increase. While among illiterates 81 percent of the respondents knew about blood donation, among the post graduates the same ratio was found to be almost cent-percent. Among various reasons cited for not donating blood, lack of awareness being the most common reason. People gathered information about blood donation from several different sources with electronic media being the most prominent. Conclusion: This study illustrates how increasing awareness and marketing ‘Voluntary blood donation’ can enhance adequacy of blood needs of a state or for that matter the entire country. This study also underlines how different media, especially electronic media, can be used to propagate altruistic blood donation. PMID:23559768

Nanographenes as electron-deficient cores of donor-acceptor systems.

PubMed

Liu, Yu-Min; Hou, Hao; Zhou, Yan-Zhen; Zhao, Xin-Jing; Tang, Chun; Tan, Yuan-Zhi; Müllen, Klaus

2018-05-15

Conjugation of nanographenes (NGs) with electro-active molecules can establish donor-acceptor π-systems in which the former generally serve as the electron-donating moieties due to their electronic-rich nature. In contrast, here we report a series of reversed donor-acceptor structures are obtained by C-N coupling of electron-deficient perchlorinated NGs with electron-rich anilines. Selective amination at the vertexes of the NGs is unambiguously shown through X-ray crystallography. By varying the donating ability of the anilino groups, the optical and assembly properties of donor-acceptor NGs can be finely modulated. The electron-deficient concave core of the resulting conjugates can host electron-rich guest molecules by intermolecular donor-acceptor interactions and gives rise to charge-transfer supramolecular architectures.

FAST TRACK COMMUNICATION: Electronic structure of a graphene/hexagonal-BN heterostructure grown on Ru(0001) by chemical vapor deposition and atomic layer deposition: extrinsically doped graphene

NASA Astrophysics Data System (ADS)

Bjelkevig, Cameron; Mi, Zhou; Xiao, Jie; Dowben, P. A.; Wang, Lu; Mei, Wai-Ning; Kelber, Jeffry A.

2010-08-01

A significant BN-to-graphene charge donation is evident in the electronic structure of a graphene/h-BN(0001) heterojunction grown by chemical vapor deposition and atomic layer deposition directly on Ru(0001), consistent with density functional theory. This filling of the lowest unoccupied state near the Brillouin zone center has been characterized by combined photoemission/k vector resolved inverse photoemission spectroscopies, and Raman and scanning tunneling microscopy/spectroscopy. The unoccupied σ*(Γ1 +) band dispersion yields an effective mass of 0.05 me for graphene in the graphene/h-BN(0001) heterostructure, in spite of strong perturbations to the graphene conduction band edge placement.

Excellent Long-Term Stability of Power Conversion Efficiency in Non-Fullerene-Based Polymer Solar Cells Bearing Tricyanovinylene-Functionalized n-Type Small Molecules.

PubMed

Ko, Eun Yi; Park, Gi Eun; Lee, Ji Hyung; Kim, Hyung Jong; Lee, Dae Hee; Ahn, Hyungju; Uddin, Mohammad Afsar; Woo, Han Young; Cho, Min Ju; Choi, Dong Hoon

2017-03-15

New small molecules having modified acceptor strength and π-conjugation length and containing dicyanovinylene (DCV) and tricyanovinylene (TCV) as a strongly electron-accepting unit with indacenodithiophene, IDT(DCV) 2 , IDT(TCV) 2 , and IDTT(TCV) 2 , were synthesized and studied in terms of their applicability to polymer solar cells with PTB7-Th as an electron-donating polymer. Intriguingly, the blended films containing IDT(TCV) 2 and IDTT(TCV) 2 exhibited superior shelf life stabilities of more than 1000 h without any reduction in the initial power conversion efficiency. The low-lying lowest unoccupied molecular orbital energy levels and robust internal morphologies of small TCV-containing molecules could afford excellent shelf life stability.

Balancing the Hydrogen Evolution Reaction, Surface Energetics, and Stability of Metallic MoS2 Nanosheets via Covalent Functionalization.

PubMed

Benson, Eric E; Zhang, Hanyu; Schuman, Samuel A; Nanayakkara, Sanjini U; Bronstein, Noah D; Ferrere, Suzanne; Blackburn, Jeffrey L; Miller, Elisa M

2018-01-10

We modify the fundamental electronic properties of metallic (1T phase) nanosheets of molybdenum disulfide (MoS 2 ) through covalent chemical functionalization, and thereby directly influence the kinetics of the hydrogen evolution reaction (HER), surface energetics, and stability. Chemically exfoliated, metallic MoS 2 nanosheets are functionalized with organic phenyl rings containing electron donating or withdrawing groups. We find that MoS 2 functionalized with the most electron donating functional group (p-(CH 3 CH 2 ) 2 NPh-MoS 2 ) is the most efficient catalyst for HER in this series, with initial activity that is slightly worse compared to the pristine metallic phase of MoS 2 . The p-(CH 3 CH 2 ) 2 NPh-MoS 2 is more stable than unfunctionalized metallic MoS 2 and outperforms unfunctionalized metallic MoS 2 for continuous H 2 evolution within 10 min under the same conditions. With regards to the entire studied series, the overpotential and Tafel slope for catalytic HER are both directly correlated with the electron donating strength of the functional group. The results are consistent with a mechanism involving ground-state electron donation or withdrawal to/from the MoS 2 nanosheets, which modifies the electron transfer kinetics and catalytic activity of the MoS 2 nanosheet. The functional groups preserve the metallic nature of the MoS 2 nanosheets, inhibiting conversion to the thermodynamically stable semiconducting state (2H) when mildly annealed in a nitrogen atmosphere. We propose that the electron density and, therefore, reactivity of the MoS 2 nanosheets are controlled by the attached functional groups. Functionalizing nanosheets of MoS 2 and other transition metal dichalcogenides provides a synthetic chemical route for controlling the electronic properties and stability within the traditionally thermally unstable metallic state.

Strategies for changing negative public attitudes toward organ donation in the People’s Republic of China

PubMed Central

Shumin, Xie; Woo, Stephanie Mu-Lian; Lei, Zhang

2014-01-01

In recent decades, the demand for organ transplantation has risen rapidly worldwide, due to an increased incidence of vital organ failure. However, the scarcity of organs appropriate for transplantation has led to an organ shortage crisis. This article retrospectively reviews strategies to change negative public attitudes toward organ donation in the People’s Republic of China. We strongly believe that efforts to publicize knowledge of organ donation, promote family discussions, train medical staff and students, establish incentive systems, and implement regulatory oversight may combat unfavorable Chinese public opinion toward organ donation and transplantation, thus potentially increasing the organ donation rate in the People’s Republic of China. PMID:24368880

Sustainable Management of Electronics

EPA Pesticide Factsheets

To provide information on EPAs strategy for electronics stewardship, certified electronics recyclers and the Challenge; as well as where to donate unwanted electronics, how to calculate benefits, and what's going on with electronics mgmt in their states.

Electronic Structure and Bonding in Transition Metal Inorganic and Organometallic Complexes: New Basis Sets, Linear Semibridging Carbonyls and Thiocarbonyls, and Oxidative Addition of Molecular Hydrogen to Square - Iridium Complexes.

NASA Astrophysics Data System (ADS)

Sargent, Andrew Landman

Approximate molecular orbital and ab initio quantum chemical techniques are used to investigate the electronic structure, bonding and reactivity of several transition metal inorganic and organometallic complexes. Modest-sized basis sets are developed for the second-row transition metal atoms and are designed for use in geometry optimizations of inorganic and organometallic complexes incorporating these atoms. The basis sets produce optimized equilibrium geometries which are slightly better than those produced with standard 3-21G basis sets, and which are significantly better than those produced with effective core potential basis sets. Linear semibridging carbonyl ligands in heterobimetallic complexes which contain a coordinatively unsaturated late transition metal center are found to accept electron density from, rather than donate electron density to, these centers. Only when the secondary metal center is a coordinatively unsaturated early transition metal center does the semibridging ligand donate electron density to this center. Large holes in the d shell around the metal center are more prominent and prevalent in early than in late transition metal centers, and the importance of filling in these holes outweighs the importance of mitigating the charge imbalance due to the dative metal-metal interaction. Semibridging thiocarbonyl ligands are more effective donors of electron density than the carbonyl ligands since the occupied donor orbitals of pi symmetry are higher in energy. The stereoselectivity of H_2 addition to d^8 square-planar transition metal complexes is controlled by the interactions between the ligands in the plane of addition and the concentrations of electronic charge around the metal center as the complex evolves from a four-coordinate to a six-coordinate species. Electron -withdrawing ligands help stabilize the five-coordinate species while strong electron donor ligands contribute only to the destabilizing repulsive interactions. The relative thermodynamic stabilities of the final complexes can be predicted based on the relative orientations of the strongest sigma-donor ligands.

Solvent as electron donor: Donor/acceptor electronic coupling is a dynamical variable

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

Castner, E.W. Jr.; Kennedy, D.; Cave, R.J.

2000-04-06

The authors combine analysis of measurements by femtosecond optical spectroscopy, computer simulations, and the generalized Mulliken-Hush (GMH) theory in the study of electron-transfer reactions and electron donor-acceptor interactions. The study focus is on ultrafast photoinduced electron-transfer reactions from aromatic amine solvent donors to excited-state acceptors. The experimental results from femtosecond dynamical measurements fall into three categories: six coumarin acceptors reductively quenched by N,N-dimethylaniline (DMA), eight electron-donating amine solvents reductively quenching coumarin 152 (7-(dimethylamino)-4-(trifluoromethyl)-coumarin), and reductive quenching dynamics of two coumarins by DMA as a function of dilution in the nonreactive solvents toluene and chlorobenzene. Applying a combination of molecular dynamicsmore » trajectories, semiempirical quantum mechanical calculations (of the relevant adiabatic electronic states), and GMH theory to the C152/DMA photoreaction, the authors calculate the electron donor/acceptor interaction parameter H{sub DA} at various time frames, H{sub DA} is strongly modulated by both inner-sphere and outer-sphere nuclear dynamics, leading us to conclude that H{sub DA} must be considered as a dynamical variable.« less

Tuning the structural and electronic properties of novel thiophene-pyrrole based 1,2,3,4-tetrazine

NASA Astrophysics Data System (ADS)

Dutta, Rakesh; Kalita, Dhruba Jyoti

2017-04-01

Here, we have studied the structural and optoelectronic behaviour of a series of conjugated heterocyclic polymers. The basic monomer unit of the conjugated polymers contains a backbone of novel thiophene and pyrrole based 1,2,3,4-tetrazine. The other oligomers are designed by substituting the basic monomer unit with different electron-donating and electron-withdrawing groups at the nitrogen and the 3rd C-atom of the pyrrole and the thiophene ring respectively. We have calculated dihedral angles, HOMO-LUMO gaps, excitation energies and oscillator strengths by employing TD-DFT method. Our study reveals that compounds having bulky substituents exhibit larger dihedral angles. This in turn renders an increase in the band gaps (ΔH - L). Presence of the electron-withdrawing substituents also increases the ΔH - L values of the oligomers. However, the electron-donating groups decrease the ΔH - L values of the oligomers. Therefore, small electron-donating substituents have an overwhelming effect on the optoelectronic properties of the conjugated polymers which in turn makes them interesting materials with good conduction properties for fabrication of optoelectronic devices such as OLEDs, OFETs and solar cells.

Mesomeric Effects of Graphene Modified with Diazonium Salts: Substituent Type and Position Influence its Properties.

PubMed

Bouša, Daniel; Jankovský, Ondřej; Sedmidubský, David; Luxa, Jan; Šturala, Jiří; Pumera, Martin; Sofer, Zdeněk

2015-12-01

In the last decade, graphene and graphene derivatives have become some of the most intensively studied materials. Tuning of the electronic and electrochemical properties of graphene is of paramount importance. In this study, six diazonium-modified graphenes containing different functional groups according to the diazonium salt precursor were investigated. These diazonium moieties have a strong mesomeric (resonance) effect and act as either electron-donating or -withdrawing species. Different graphene precursors, such as thermally and chemically reduced graphenes were studied. All the products were characterized in detail by elemental combustion analysis, FTIR spectroscopy, Raman spectroscopy, high-resolution X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry. Resistivity and zeta potential measurements were consistent with theoretical (DFT) calculations. The results show that chemical modification of graphene by diazotation strongly influences its properties, creating a huge application potential in microelectronics, energy storage and conversion devices, and electrocatalysis. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Donation of peripheral blood stem cells to unrelated strangers: A thematic analysis

PubMed Central

Billen, Annelies; Madrigal, J. Alejandro; Scior, Katrina; Shaw, Bronwen E.; Strydom, Andre

2017-01-01

Background Donation of haematopoietic stem cells, either through bone marrow (BM) or peripheral blood stem cell (PBSC) collection, is a generally safe procedure for healthy donors, although side effects are a known risk. Previous research, including our recent quantitative study, has shown that the psychosocial response to donating is usually a positive one and most donors would be willing to donate again in the future. This is often despite experiencing significant side effects during the donation process. Due to the relative recent introduction of PBSC, a comprehensive understanding of the range of physical and emotional issues donors may experience is lacking, as well as an understanding of specific donor characteristics Qualitative research can provide rich narrative data into these areas. This study was set up in order to identify specific donor characteristics and to further explore the relationship between pre-donation physical health and the donation experience, as previously identified in our quantitative study. Methods It involved in-depth telephone interviews with 14 PBSC donors who participated in our original quantitative study. Thematic analysis was used to analyse the findings and the results provide a summary of participants’ characteristics using themes and constituent codes. Results We identified several donor characteristics, including strong intrinsic motivation, altruism, sense of duty, determination, low levels of ambivalence and the ability to develop a strong emotional relationship with an (unknown/anonymous) recipient whilst being able to manage strong feelings and emotions. Conclusions These personality traits may explain the resilience that has been observed previously in haematopoietic stem cells donors. Significant feelings of grief were reported after a recipient’s death. Possibilities to alleviate these symptoms may include raising awareness of potential poor outcomes in the recipient and offering improved counselling services if the recipient dies. We acknowledge several limitations including the sampling frame. PMID:29069088

The spectroscopic impact of interactions with the four Gouterman orbitals from peripheral decoration of porphyrins with simple electron withdrawing and donating groups.

PubMed

Zhang, Angel; Kwan, Lydia; Stillman, Martin J

2017-11-07

Tetrapyrroles are of great interest for solar cell and photodynamic therapy applications due to their structural analogy with chlorophyll, a natural photosensitizer. Unsubstituted symmetric porphyrins exhibit weak absorption in the red region which makes them unsuitable for these applications. The push-pull peripheral decoration modifies the energies of the frontier molecular orbitals, which in turn influences the tetrapyrrole's spectroscopic properties. The absorption, magnetic circular dichroism, and emission spectra were measured for four zinc tetratolylporphyrin compounds substituted peripherally with a fused dimethoxybenzo group as an electron withdrawing group (EWG) on one pyrrole and on the opposite pyrrole, a single acetamido (1), a nitro (2), a proton (3), or a benzoylamino (4) substituent. Unusually, the magnetic circular dichroism spectrum of 2 exhibited a negative A term for the lowest energy absorption band (the Q band) and its emission spectrum was also unlike those of 1, 3, and 4. A complete computational analysis was carried out to obtain the energies and electron distribution, shown by electron density surfaces, of the four Gouterman MOs. TD-DFT calculations showed that for 2, ΔLUMO was greater than ΔHOMO, which accounted for the observed negative A term. The trend in the estimated MCD A term magnitudes, normalized to the absorbance as [A/(dipole strength) BM], provides experimental confirmation of the computationally determined ratio of ΔLUMO/ΔHOMO data. The value of ΔHOMO was confirmed by the trend in oscillator strengths. A series of fictive porphyrins (F1-F5) incorporating simple push-pull substituents were designed and their electronic structures were investigated using TD-DFT calculations. The substituents in the five fictive molecules illustrate the differential effect of the donor and acceptor groups in the β-position of the pyrroles on the relative stabilities of the four Gouterman orbitals. NO 2 groups result in the greatest splitting of the LUMO pair. We show that on using strong EWGs, opposite electron donating groups result in a ΔLUMO > 0, which red-shifts the Q band and introduces a strong dipole. With the nitro and formyl EWGs, ΔLUMO becomes greater than ΔHOMO, resulting in a complex electronic structure of the Q band, recognizable by a negative A term suggesting a design objective for future photosensitizers.

Public support for intergenerational oocyte donation in the United States.

PubMed

Bortoletto, Pietro; Farland, Leslie V; Ginsburg, Elizabeth S; Goldman, Randi H

2018-02-01

To determine whether the general public supports intergenerational oocyte donation. Cross-sectional study. Not applicable. A nationally representative sample based on age distribution of United States residents. Not applicable. Characteristics of respondents who supported (strongly agree and agree) various oocyte donation practices were compared with participants who did not support them (disagree and strongly disagree) using log binomial regression to calculate risk ratios (RRs) and 95% confidence intervals of support (95% CIs). Models were adjusted for age, gender, and religion to yield adjusted risk ratios (aRR). A total of 1,915 people responded to the Web-based survey; 53% were female, and 24% were racial/ethnic minorities. Eighty-five percent had prior knowledge of oocyte donation, and 74% felt that a woman should be able to donate oocytes to a family member. The desire to help a family member was the most commonly perceived motivation for donors (79%). Christian-Catholics compared with Christian-non-Catholics (aRR 0.91, 95% CI 0.86-0.98), African Americans compared with non-Hispanic Caucasians (aRR 0.86, 95% CI 0.76-0.97), and Republicans compared with Democrats (RR 0.93, 95% CI 0.88-0.98) were less likely to support intergenerational oocyte donation. Respondents with three or more biological children (RR 1.06, 95% CI 1.00-1.11) compared with those with no children were less likely to support this practice. Eight percent of participants disapproved of donation to any family member. The most common reason for disapproval was the potential negative impact on the child (53%). A majority of Americans support the practice of intergenerational oocyte donation; however, support varies according to demographic characteristics. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Reduced social preferences in autism: evidence from charitable donations

PubMed Central

2012-01-01

Background People with autism have abnormal preferences, ranging from an apparent lack of preference for social stimuli to unusually strong preferences for restricted sets of highly idiosyncratic stimuli. Yet the profile of preferences across social and nonsocial domains has not been mapped out in detail, and the processes responsible remain poorly understood. Methods To assess preferences across a range of stimuli, we measured real monetary donations to 50 charities spanning categories pertaining to people, mental health, animals, or the environment. We compared the donations made by 16 high-functioning adults with autism to those made by neurotypical controls matched on age, gender and education. We additionally collected ratings of how people evaluated the different charities. Results Compared with controls, high-functioning adults with autism donated less overall and also showed a significantly disproportionate reduction in donations to people charities compared with donations to the other charities. Furthermore, whereas controls discriminated strongly between different people charities, choosing to donate a lot of money to some and very little to others, much less discrimination was seen in the autism group. Ratings that probed how participants constructed their preferences did not differ between groups, except for a difference in the perceived impact of pictures and text information about people charities. Strikingly, there were some charities related to mental health, and autism in particular, to which the autism group donated considerably more than did the controls. Conclusions People with autism were found to have reduced preference and sensitivity towards charities benefiting other people. The findings provide evidence for a domain-specific impairment in social cognition in autism spectrum disorder, and in particular in linking otherwise intact social knowledge to the construction of value signals on which preferences regarding other people are based. PMID:22958506

Reduced social preferences in autism: evidence from charitable donations.

PubMed

Lin, Alice; Tsai, Karin; Rangel, Antonio; Adolphs, Ralph

2012-05-17

People with autism have abnormal preferences, ranging from an apparent lack of preference for social stimuli to unusually strong preferences for restricted sets of highly idiosyncratic stimuli. Yet the profile of preferences across social and nonsocial domains has not been mapped out in detail, and the processes responsible remain poorly understood. To assess preferences across a range of stimuli, we measured real monetary donations to 50 charities spanning categories pertaining to people, mental health, animals, or the environment. We compared the donations made by 16 high-functioning adults with autism to those made by neurotypical controls matched on age, gender and education. We additionally collected ratings of how people evaluated the different charities. Compared with controls, high-functioning adults with autism donated less overall and also showed a significantly disproportionate reduction in donations to people charities compared with donations to the other charities. Furthermore, whereas controls discriminated strongly between different people charities, choosing to donate a lot of money to some and very little to others, much less discrimination was seen in the autism group. Ratings that probed how participants constructed their preferences did not differ between groups, except for a difference in the perceived impact of pictures and text information about people charities. Strikingly, there were some charities related to mental health, and autism in particular, to which the autism group donated considerably more than did the controls. People with autism were found to have reduced preference and sensitivity towards charities benefiting other people. The findings provide evidence for a domain-specific impairment in social cognition in autism spectrum disorder, and in particular in linking otherwise intact social knowledge to the construction of value signals on which preferences regarding other people are based.

TFB:TPDSi2 interfacial layer usable in organic photovoltaic cells

DOEpatents

Marks, Iobin J [Evanston, IL; Hains, Alexander W [Evanston, IL

2011-02-15

The present invention, in one aspect, relates to a solar cell. In one embodiment, the solar cell includes an anode; an active organic layer comprising an electron-donating organic material and an electron-accepting organic material; and an interfacial layer formed between the anode and active organic layer, where the interfacial layer comprises a hole-transporting polymer characterized with a hole-mobility higher than that of the electron-donating organic material in the active organic layer, and a small molecule that has a high hole-mobility and is capable of crosslinking on contact with air.

2016 America's Recycle Day

NASA Image and Video Library

2016-11-15

A sign points the way to the electronic waste collection site, where NASA Kennedy Space Center employees donated computers, monitors, vacuum cleaners and other electronics in conjunction with America Recycles Day. America Recycles Day is a nationally recognized initiative dedicated to promoting recycling in the United States. Kennedy partnered with several organizations in order to donate as many of the items as possible to those who could use them the most in the Space Coast community. Space center personnel brought in electronic waste, gently used household goods, clothing and more. The two-day event was sponsored by Kennedy's Sustainability team.

Electronic Tool for Distribution and Allocation of Heart on Donation and Transplantation in Mexico.

PubMed

Maqueda Tenorio, S E; Meixueiro Daza, L A; Maqueda Estrada, S

2016-03-01

In Mexico and globally, organs and/or tissues donated from deceased people are insufficient to cover the demand for transplants. In 2014, a rate of 3.6 organ donors per million in habitants was recorded; this is reflected in the transplants performed, including heart transplantation, with a rate of 0.4 per million population. According to the legal framework of Mexico, the National Transplant Center is responsible for coordinating National Subsystem of donation and transplantation, and one of its functions is to integrate and backup information regarding donation and transplantation through the National Transplant Registry System. In July 2015, 45 people were registered in the database of patients waiting for a heart transplant, of which 34.61% were female recipients and 65.39% male. Distribution and allocation processes are a key element to provide a fair distribution for those patients waiting for that organ; thus the creation of an electronic tool is proposed, one that aims to support the decision of the donation and/or transplants coordination committee by providing the necessary elements to make this process more efficient. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of word-of-mouth on the behavior of Austrian blood donors: a case study of the Red Cross Blood Donation Service.

PubMed

Martin, Sebastian; Greiling, Dorothea; Leibetseder, Nina

2017-12-13

The procurement of blood is an essential challenge of today's health care. Current studies emphasize the influence of word-of-mouth (WOM) on health care behavior, including blood donation. Still, there exists no study which systematically investigates how WOM affects the behavior of blood donors. Therefore, this paper aims to contribute to this lack of research by focusing on Austrian blood donors as possible receivers and senders of WOM. A survey was distributed to 300 donors of the Austrian Red Cross with a return of 245 surveys. The results highlight the strong influence of WOM on the awareness of the blood service and the willingness to donate blood. Further, structured and organized procedures, friendly employees and respectful interaction were found to be important factors determining willingness to recommend blood donation. Family members as well as friends are the preferred WOM-receivers and the personal face-to-face contact is the favored channel of communication. The results also show that WOM-behavior is strongly influenced by factors such as age, gender and donation frequency. By helping blood bank managers to better understand how WOM affects donation intention and behavior, this study provides a new approach to attract blood donors. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Tracking bacterial infection of macrophages using a novel red-emission pH sensor.

PubMed

Jin, Yuguang; Tian, Yanqing; Zhang, Weiwen; Jang, Sei-Hum; Jen, Alex K-Y; Meldrum, Deirdre R

2010-10-01

The relationship between bacteria and host phagocytic cells is key to the induction of immunity. To visualize and monitor bacterial infection, we developed a novel bacterial membrane permeable pH sensor for the noninvasive monitoring of bacterial entry into murine macrophages. The pH sensor was constructed using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran (TCF) as an electron-withdrawing group and aniline as an electron-donating group. A piperazine moiety was used as the pH-sensitive group. Because of the strong electron-donating and -withdrawing units conjugated in the sensing moiety M, the fluorophore emitted in the red spectral window, away from the autofluorescence regions of the bacteria. Following the engulfment of sensor-labeled bacteria by macrophages and their subsequent merger with host lysosomes, the resulting low-pH environment enhances the fluorescence intensity of the pH sensors inside the bacteria. Time-lapse analysis of the fluorescent intensity suggested significant heterogeneity of bacterial uptake among macrophages. In addition, qRT-PCR analysis of the bacterial 16 S rRNA gene expression within single macrophage cells suggested that the 16 S rRNA of the bacteria was still intact 120 min after they had been engulfed by macrophages. A toxicity assay showed that the pH sensor has no cytotoxicity towards either E. coli or murine macrophages. The sensor shows good repeatability, a long lifetime, and a fast response to pH changes, and can be used for a variety of bacteria.

Indian ICU nurses' perceptions of and attitudes towards organ donation.

PubMed

Vijayalakshmi, Poreddi; Nagarajaiah; Ramachandra; Math, Suresh Bada

Nurses play a significant role in identifying and securing potential organ donors in the clinical environment. Research among Indian nurses related to organ donation is sparse. The present study aimed to investigate nurses' attitudes towards organ donation. A cross-sectional descriptive survey was carried out among nurses (n=184) at a tertiary care centre. Data were collected through self-report questionnaire. A majority (81%) of the respondents were 'willing to sign the card' for organ donation; however, only 3.8% (n=7) of them actually 'signed the organ donation card'. There were significant associations found between intentions to sign the organ donation card and gender (x2=5.852; p<0.054), religion (x2=40.175; p<0.000), and experience caring for brain-dead patients (x2=22.790; p<0.001). The researchers strongly suggest continuing education for nurses to enhance skills and knowledge, as well as sensitivity to cultural, ethical, social, and religious issues, and advocacy in the area of organ donation. Furthermore, nurse administrators must take the initiative to develop guidelines clarifying the role of nurses in the organ donation and transplantation process to promote organ donation and improve rates.

Evaluation of an educational, theater-based intervention on attitudes toward organ donation in Risaralda, Colombia

PubMed Central

Buitrago, Juliana; Gómez, Sandra; Guerra, Alvaro; Lucumí, Leidy; Romero, César

2013-01-01

Introduction: The shortage of organs for transplantation is a worldwide problem and the main cause is the refusal of family members to donate. Consent to donate is influenced by many factors and educational interventions are strongly recommended. Objective: To evaluate the impact of an educational, theaterbased strategy on the attitudes toward organ donation. Methods: This study employed an intervention using theater as the central tool. The impact of this intervention on the intention to donate was assessed through a controlled, prospective, nonrandomized designed study. The sample consisted of 1,038 people. All the participants answered a survey that asked about sex, age and intent to donate. Afterward, one portion of the sample was exposed to the play, The Gift of Life, and a subsequent discussion forum that was guided by experts. The same survey was administered again after the intervention. Results: Before the intervention, donation attitudes were positive in 68.3% of the responses, negative in 6.8% and uncertain in 24.9%. Females showed a greater intent to donate while age had no apparent influence on the donation decision. Those exposed to the intervention were found to be more likely to donate and show a favorable change in attitude toward donation than those who were not exposed to the intervention. Conclusion: An educational intervention using theater is an effective tool to generate a short-term change in the intent to donate. Educational strategies should be employed to increase the rates of organ donation. PMID:24892320

Conscientious objection to deceased organ donation by healthcare professionals.

PubMed

Shaw, David; Gardiner, Dale; Lewis, Penney; Jansen, Nichon; Wind, Tineke; Samuel, Undine; Georgieva, Denie; Ploeg, Rutger; Broderick, Andrew

2018-02-01

In this article, we analyse the potential benefits and disadvantages of permitting healthcare professionals to invoke conscientious objection to deceased organ donation. There is some evidence that permitting doctors and nurses to register objections can ultimately lead to attitudinal change and acceptance of organ donation. However, while there may be grounds for conscientious objection in other cases such as abortion and euthanasia, the life-saving nature of donation and transplantation renders objection in this context more difficult to justify. In general, dialogue between healthcare professionals is a more appropriate solution, and any objections must be justified with a strong rationale in hospitals where such policies are put in place.

2016 America's Recycle Day

NASA Image and Video Library

2016-11-15

Computers, monitors, vacuum cleaners and other electronics have been donated by employees at NASA's Kennedy Space Center in Florida in conjunction with America Recycles Day. America Recycles Day is a nationally recognized initiative dedicated to promoting recycling in the United States. Kennedy partnered with several organizations in order to donate as many of the items as possible to those who could use them the most in the Space Coast community. Space center personnel brought in electronic waste, gently used household goods, clothing and more.

Increasing the supply of kidneys for transplantation by making living donors the preferred source of donor kidneys.

PubMed

Testa, Giuliano; Siegler, Mark

2014-12-01

At the present time, increasing the use of living donors offers the best solution to the organ shortage problem. The clinical questions raised when the first living donor kidney transplant was performed, involving donor risk, informed consent, donor protection, and organ quality, have been largely answered. We strongly encourage a wider utilization of living donation and recommend that living donation, rather than deceased donation, become the first choice for kidney transplantation. We believe that it is ethically sound to have living kidney donation as the primary source for organs when the mortality and morbidity risks to the donor are known and kept extremely low, when the donor is properly informed and protected from coercion, and when accepted national and local guidelines for living donation are followed.

Superoxide Stabilization and a Universal KO2 Growth Mechanism in Potassium-Oxygen Batteries.

PubMed

Wang, Wanwan; Lai, Nien-Chu; Liang, Zhuojian; Wang, Yu; Lu, Yi-Chun

2018-04-23

Rechargeable potassium-oxygen (K-O 2 ) batteries promise to provide higher round-trip efficiency and cycle life than other alkali-oxygen batteries with satisfactory gravimetric energy density (935 Wh kg -1 ). Exploiting a strong electron-donating solvent, for example, dimethyl sulfoxide (DMSO) strongly stabilizes the discharge product (KO 2 ), resulting in significant improvement in electrode kinetics and chemical/electrochemical reversibility. The first DMSO-based K-O 2 battery demonstrates a much higher energy efficiency and stability than the glyme-based electrolyte. A universal KO 2 growth model is developed and it is demonstrated that the ideal solvent for K-O 2 batteries should strongly stabilize superoxide (strong donor ability) to obtain high electrode kinetics and reversibility while providing fast oxygen diffusion to achieve high discharge capacity. This work elucidates key electrolyte properties that control the efficiency and reversibility of K-O 2 batteries. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Increased Electron-Accepting and Decreased Electron-Donating Capacities of Soil Humic Substances in Response to Increasing Temperature.

PubMed

Tan, Wenbing; Xi, Beidou; Wang, Guoan; Jiang, Jie; He, Xiaosong; Mao, Xuhui; Gao, Rutai; Huang, Caihong; Zhang, Hui; Li, Dan; Jia, Yufu; Yuan, Ying; Zhao, Xinyu

2017-03-21

The electron transfer capacities (ETCs) of soil humic substances (HSs) are linked to the type and abundance of redox-active functional moieties in their structure. Natural temperature can affect the chemical structure of natural organic matter by regulating their oxidative transformation and degradation in soil. However, it is unclear if there is a direct correlation between ETC of soil HS and mean annual temperature. In this study, we assess the response of the electron-accepting and -donating capacities (EAC and EDC) of soil HSs to temperature by analyzing HSs extracted from soil set along glacial-interglacial cycles through loess-palaeosol sequences and along natural temperature gradients through latitude and altitude transects. We show that the EAC and EDC of soil HSs increase and decrease, respectively, with increasing temperature. Increased temperature facilitates the prevalence of oxidative degradation and transformation of HS in soils, thus potentially promoting the preferentially oxidative degradation of phenol moieties of HS or the oxidative transformation of electron-donating phenol moieties to electron-accepting quinone moieties in the HS structure. Consequently, the EAC and EDC of HSs in soil increase and decrease, respectively. The results of this study could help to understand biogeochemical processes, wherein the redox functionality of soil organic matter is involved in the context of increasing temperature.

Supramolecular assemblies of a nitrogen-embedded buckybowl dimer with C60† †Electronic supplementary information (ESI) available. CCDC 1579079 and 1579080. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7sc04453d

PubMed Central

Yokoi, Hiroki; Sakamaki, Daisuke; Seki, Shu

2017-01-01

A directly connected azabuckybowl dimer was synthesized via a palladium-catalysed C–H/C–Br coupling. The electron-donating nature of the pyrrolic nitrogen atoms of the azabuckybowl enabled a strong complexation with pristine C60. In the presence of two equivalents of C60, the azabuckybowl dimer formed crystals with a 1 : 2 stoichiometry. Conversely, in diluted solution, complexes with a 1 : 1 stoichiometry of the dimer and C60 were detected predominantly, and these precipitated upon increasing the concentration of C60. Scanning electron microscopy images of the precipitate showed fibre-like aggregates, indicating the formation of supramolecular assemblies with 1D chain structures. A variable-temperature 1H NMR analysis revealed that the precipitate consists of the dimer and C60 in a 1 : 1 ratio. PMID:29629149

Balancing the Hydrogen Evolution Reaction, Surface Energetics, and Stability of Metallic MoS 2 Nanosheets via Covalent Functionalization

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

Benson, Eric E.; Zhang, Hanyu; Schuman, Samuel A.

We modify the fundamental electronic properties of metallic (1T phase) nanosheets of molybdenum disulfide (MoS 2) through covalent chemical functionalization, and thereby directly influence the kinetics of the hydrogen evolution reaction (HER), surface energetics, and stability. Chemically exfoliated, metallic MoS 2 nanosheets are functionalized with organic phenyl rings containing electron donating or withdrawing groups. We find that MoS 2 functionalized with the most electron donating functional group (p-(CH 3CH 2) 2NPh-MoS 2) is the most efficient catalyst for HER in this series, with initial activity that is slightly worse compared to the pristine metallic phase of MoS 2. The p-(CHmore » 3CH 2) 2NPh-MoS 2 is more stable than unfunctionalized metallic MoS 2 and outperforms unfunctionalized metallic MoS 2 for continuous H 2 evolution within 10 min under the same conditions. With regards to the entire studied series, the overpotential and Tafel slope for catalytic HER are both directly correlated with the electron donating strength of the functional group. The results are consistent with a mechanism involving ground-state electron donation or withdrawal to/from the MoS 2 nanosheets, which modifies the electron transfer kinetics and catalytic activity of the MoS 2 nanosheet. The functional groups preserve the metallic nature of the MoS 2 nanosheets, inhibiting conversion to the thermodynamically stable semiconducting state (2H) when mildly annealed in a nitrogen atmosphere. We propose that the electron density and, therefore, reactivity of the MoS 2 nanosheets are controlled by the attached functional groups. Functionalizing nanosheets of MoS 2 and other transition metal dichalcogenides provides a synthetic chemical route for controlling the electronic properties and stability within the traditionally thermally unstable metallic state.« less

Balancing the Hydrogen Evolution Reaction, Surface Energetics, and Stability of Metallic MoS 2 Nanosheets via Covalent Functionalization

DOE PAGES

Benson, Eric E.; Zhang, Hanyu; Schuman, Samuel A.; ...

2017-12-27

We modify the fundamental electronic properties of metallic (1T phase) nanosheets of molybdenum disulfide (MoS 2) through covalent chemical functionalization, and thereby directly influence the kinetics of the hydrogen evolution reaction (HER), surface energetics, and stability. Chemically exfoliated, metallic MoS 2 nanosheets are functionalized with organic phenyl rings containing electron donating or withdrawing groups. We find that MoS 2 functionalized with the most electron donating functional group (p-(CH 3CH 2) 2NPh-MoS 2) is the most efficient catalyst for HER in this series, with initial activity that is slightly worse compared to the pristine metallic phase of MoS 2. The p-(CHmore » 3CH 2) 2NPh-MoS 2 is more stable than unfunctionalized metallic MoS 2 and outperforms unfunctionalized metallic MoS 2 for continuous H 2 evolution within 10 min under the same conditions. With regards to the entire studied series, the overpotential and Tafel slope for catalytic HER are both directly correlated with the electron donating strength of the functional group. The results are consistent with a mechanism involving ground-state electron donation or withdrawal to/from the MoS 2 nanosheets, which modifies the electron transfer kinetics and catalytic activity of the MoS 2 nanosheet. The functional groups preserve the metallic nature of the MoS 2 nanosheets, inhibiting conversion to the thermodynamically stable semiconducting state (2H) when mildly annealed in a nitrogen atmosphere. We propose that the electron density and, therefore, reactivity of the MoS 2 nanosheets are controlled by the attached functional groups. Functionalizing nanosheets of MoS 2 and other transition metal dichalcogenides provides a synthetic chemical route for controlling the electronic properties and stability within the traditionally thermally unstable metallic state.« less

Efficient n-doping of graphene films by APPE (aminophenyl propargyl ether): a substituent effect.

PubMed

Kim, Youngsoo; Yoo, Je Min; Jeon, Hak Rim; Hong, Byung Hee

2013-11-14

We report the synthesis and applications of APPE (aminophenyl propargyl ether) as a novel n-type dopant for graphene. The characteristics of APPE-doped graphene films were investigated using Raman spectroscopy as well as electron transport measurements. The Raman 2D/G peak ratio decreased by more than 40%, and the minimum conductivity voltage (Dirac voltage) was shifted to -133 V as the pristine graphene was doped with APPE, indicating that the graphene was strongly n-doped. We suppose that the electron donating property of the amine group (-NH2) is the origin of such an intense n-doping effect. In contrast, a similar molecule with an electron withdrawing nitro group (-NO2) (nitrophenyl propargyl ether, NPPE) showed a slight p-doping effect. Thus, we conclude that the doping effect of a molecular framework strongly depends on the functional substituents, which can be represented by the Hammett equation. We also confirmed that the sheet resistance of the APPE doped graphene film was reduced by ∼70%, which is crucial to enhance the electrical conductivity of graphene for various electronic applications. In addition, the acetylene group of APPE appears promising to be utilized in "click chemistry" to further functionalize the π-surface of graphene for sensors and bio applications.

Substitution and solvent effects in the chalcones isomerization barrier of flavylium photochromic systems.

PubMed

Roque, Ana; Lima, João Carlos; Parola, A Jorge; Pina, Fernando

2007-04-01

Useful application of photochromic compounds as optical memories implies the existence of a large kinetic barrier between the forms interconverted by light. In the case of flavylium salts, the ground state isomerization barrier between the photoisomerizable chalcone isomers is shown to correlate with the electron donating ability of the substituents, measured by their effects in the (1)H NMR chemical shifts of the aromatic protons. Substitution with electron donating groups in ring A lowers the barrier while substitution at ring B has the opposite effect. However, in water, the observed increase is higher than expected in the case of compound 4',9-dihydroxychalcone when compared with the analogous 4'-dimethylamino-9-hydroxychalcone, containing a better electron donating group in the same position. Our interpretation is that the water network is providing an efficient pathway to form tautomers. In acetonitrile, unlike water, the expected order is indeed observed: E(a)(4',9-dihydroxychalcone) = 60 kJ mol(-1) < E(a) (4'-dimethylamino-9-hydroxychalcone) = 69 kJ mol(-1).

Positron annihilation studies in solid substituted aromatic compounds

NASA Astrophysics Data System (ADS)

Oliveira, F. C.; Oliveira, A. M.; Donnici, C. L.; Machado, J. C.; Magalhães, W. F.; Windmöller, D.; Fulgêncio, F. H.; Souza, L. R.

2011-04-01

Positronium formation was investigated in benzene and naphthalene compounds with electron donating (sbnd NH2 and sbnd OH) and electron withdrawing (sbnd CN and sbnd NO2) substituents. The results exhibit an increase in the positronium formation yield whenever donating groups are bound to the ring and a decrease with withdrawing groups. These results can be attributed to the π-system electronic density variation in the aromatic ring. The amount of positronium obtained, I3 parameter, has been correlated with the Hammett (σ) and Brown-Okamoto (σp+) constants and adjusted through the modified Hammett equation, which employs the ratio I3/I3ϕ, yielding a satisfactory fit.

Antioxidant activity of selenenamide-based mimic as a function of the aromatic thiols nucleophilicity, a DFT-SAPE model.

PubMed

Kheirabadi, Ramesh; Izadyar, Mohammad

2018-05-18

The mechanism of action of the selenenamide 1 as a mimic of the glutathione peroxidase (GPx) was investigated by the density functional theory. The solvent-assisted proton exchange procedure was applied to model the catalytic behavior and antioxidant activity of this mimic. To have an insight into the charge transfer effect, different aromatic thiols, including electron donating substituents on the phenyl ring were considered. The catalytic behavior of the selenenamide was modeled in a four-step mechanism, described by the oxidation of the mimic, the reduction of the obtained product, selenoxide, the reduction of the selenenylsulfide and dehydration of selenenic acid. On the basis of the activation parameters, the final step of the proposed mechanism is the rate determining states of the catalytic cycle. Turnover frequency (TOF) analysis showed that the electron donating groups at the para-position of the phenyl ring of the PhSH do not affect the catalytic activity of the selenenamide in contrast to p-methyl thiophenol which indicates the highest nucleophilicity. The evaluation of the electronic contribution of the various donating groups on the phenyl ring of the aromatic thiols shows that the antioxidant activity of the selenenamide sufficiently increases in the presence of the electron-donating substitutions. Finally, the charge transfer process at the rate-determining state was investigated based on the natural bond orbital analysis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Improving first-time donor attendance rates through the use of enhanced donor preparation materials.

PubMed

Masser, Barbara; France, Christopher R; Foot, Jayne; Rozsa, Amy; Hayman, Jane; Waller, Daniel; Hunder, Everard

2016-06-01

Many nondonors are positive about blood donation and this motivates booking an appointment to donate. However, as their appointment approaches barriers to donating-such as anxiety-may become salient and deter attendance. Building on research of France and colleagues demonstrating the positive effect of enhanced preparation materials on donor recruitment, this study sought to determine whether these materials could effectively boost first donation appointment attendance. A field study comprising a 3 (brochure: none, e-mail, hard copy) × 2 (national call center [NCC] contact: none, call) between-subjects design was conducted with 3646 nondonors who had scheduled their first appointment. Participants in the brochure conditions received either a hard copy or an e-mailed link to electronic materials modeled on the donor preparation research of France and colleagues. Participants in the NCC call condition also received a call scripted in line with these preparation materials. The key outcome was new donor attendance rate. Although first-appointment attendance rates were high in the control (no additional contact) condition at 85.07% of those not canceling in advance, dual exposure to the preparation materials through a NCC call and an electronic brochure boosted attendance. The relative risk of attending in the NCC call and electronic brochure condition was 1.0836 (95% confidence interval, 1.0352-1.1343; p = 0.0006), with attendance 8.36% higher than in the control. This gain in attendance came at a relative increase in recruitment costs of 2%. The use of tailored communication to address new donors' concerns and prepare them for donating bolsters attendance rates. © 2016 AABB.

Conscientious objection to deceased organ donation by healthcare professionals

PubMed Central

Gardiner, Dale; Jansen, Nichon; Wind, Tineke; Samuel, Undine; Georgieva, Denie; Ploeg, Rutger; Broderick, Andrew

2017-01-01

In this article, we analyse the potential benefits and disadvantages of permitting healthcare professionals to invoke conscientious objection to deceased organ donation. There is some evidence that permitting doctors and nurses to register objections can ultimately lead to attitudinal change and acceptance of organ donation. However, while there may be grounds for conscientious objection in other cases such as abortion and euthanasia, the life-saving nature of donation and transplantation renders objection in this context more difficult to justify. In general, dialogue between healthcare professionals is a more appropriate solution, and any objections must be justified with a strong rationale in hospitals where such policies are put in place. PMID:29456600

[Current trends in gamete donation - psychosocial and ethical issues].

PubMed

Rumpíková, T; Oborná, I; Konečná, H

2017-01-01

To overview contemporary knowledge of legal and psychosocial rules in gamete donation. Previously, anonymous donation was preferred and recommended by experts but currently, with respect to the right to know the genetic origin of individuals, the relation to donor anonymity was reconsidered in many countries. There is a growing tendency to introduce the open identity system in gamete donation. Such system may guarantee that the child born after gamete donation may have receive the identification data of the donor of gametes. A review. Clinic of Reproductive Medicine and Gynecology Zlin. An overview of recent literature evaluating the influence of donor anonymity vs. open identity on psychosocial development of children born after gamete donation as well as on the quality of the relationship between parents and children in such families. New medical technologies usually overtake the developmental speed of ethics and psychology, and their impact on human society. Current trend to open identity is strong but there is no clear evidence that the open identity is of real importance for the healthy psychosocial development of a child born after gamete donation. Furthermore, there is no evidence that anonymity and secrecy of the gamete donation is harmful. In case of the consideration of the change in legal regulation in anonymity/open identity in gamete donation we would suggest the thorough consideration of all consequences.

Impression management during evaluation and psychological reactions post-donation of living kidney donors.

PubMed

Hildebrand, Lee; Melchert, Timothy P; Anderson, Rebecca C

2014-08-01

Many healthcare providers have been concerned about the extent to which potential kidney donors use impression management or concealment of important information regarding their medical history, current functioning, or other circumstances that could affect whether they are accepted as donors. To date, however, there has been very little empirical examination of these questions. It is also not known whether donors' use of impression management pre-donation is related to their reactions and adjustment post-donation. This study surveyed 76 individuals who had donated a kidney one to six yr previously regarding their use of impression management and their concealing of information during their psychological evaluations. They were also asked about their reactions to the donation and whether they would make the same decision again. In addition, 21 of these donors participated in focus groups that explored these questions in depth. Many of the kidney donors reported that they possessed very strong motivation to donate and consequently used impression management in their interactions with medical professionals pre-donation. Very few donors, however, indicated that they concealed information during their pre-donation evaluations. The donors' psychological reactions post-donation were generally positive, and nearly all indicated that they would make the same decision again. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Ron Leuschner donates over 11,000 specimens of Pyraloidea to the National Museum of Natural History

USDA-ARS?s Scientific Manuscript database

Ron Leuschner, Past President of the Lepidopterists’ Society, donated over 11,000 specimens of the Pyraloidea to the National Museum of Natural History, Smithsonian Institution, Washington, DC. This collection is strongly represented by specimens from the western United States and may prove to be on...

A systematic review and meta-analysis of antecedents of blood donation behavior and intentions.

PubMed

Bednall, Timothy C; Bove, Liliana L; Cheetham, Ali; Murray, Andrea L

2013-11-01

This meta-analysis sought to identify the strongest antecedents of blood donation behavior and intentions. It synthesized the results of 24 predictive correlational studies of donation behavior and 37 studies of donation intentions. The antecedents were grouped into six research programs: (1) the Theory of Planned Behavior (TPB) and its extensions, (2) prosocial motivation, (3) affective expectations, (4) donor site experience, (5) past donation behavior, and (6) donor demographics. Antecedent categories were cross-validated by multiple coders, and combined effect sizes were analyzed using a random-effects model. For donation behavior, medium positive associations were found with five of the constructs from the extended TPB: intentions to donate, perceived behavioral control, attitude toward donation, self-efficacy and donor role identity. Other antecedents displaying a positive association with donation behavior included anticipated regret for not donating, number of past donations and donor age. Donor experiences at the collection site in the form of temporary deferral or adverse reactions had a medium negative association with behavior. For donation intentions, strong positive associations were observed for perceived behavioral control, attitude, self-efficacy, role identity and anticipated regret. Medium positive associations were observed for personal moral norm, subjective norm, satisfaction, and service quality. All other potential antecedents had weak or non-significant associations with behavior and intentions. Several of these associations were moderated by between-study differences, including donor experience, the period of data collection in which donation behavior was observed, and the use of a nominal (yes/no return) versus a ratio measure of donation behavior. Collectively, the results underscore the importance of enhancing donors' attitudes towards donation and building their perceived behavioral control and self-efficacy to donate. Further, minimizing the risk of adverse reactions and enacting re-recruitment policies for temporarily deferred donors will help protect future donation behavior. Implications of these findings for blood collection agencies and researchers are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Characteristics of donors who do or do not return to give blood and barriers to their return

PubMed Central

Wevers, Anne; Wigboldus, Daniël H.J.; de Kort, Wim L.A.M.; van Baaren, Rick; Veldhuizen, Ingrid J.T.

2014-01-01

Background In the Netherlands about 50% of whole blood donors return to give blood after an invitation to donate. This study aimed to investigate the characteristics of donor return behaviour and to gain insight into the barriers to blood donation reported by the donors themselves. Materials and methods A total of 4,901 whole blood donors were invited to donate in week 39 of 2009. Barriers mentioned by donors who informed the blood bank for not donating were registered for 1 month. Logistic regression analyses assessed relevant characteristics of return behaviour, such as age and blood type, in men and women separately. Results Of the invited donors, 55% returned to give a donation, whereas 45% did not return. Male donors were more likely to return when they were older, had a higher previous return rate and had no past deferrals. The same pattern was found among women, but was less strong. The main barriers were: time constraints (35%), preference to postpone donation due to general physical problems although being eligible to donate (29%), and being ineligible to donate due to medical deferral criteria (9%). Discussion Specific donor characteristics are associated with return behaviour. Not donating due to time constraints could mean that donors do not feel the urgency of donating blood. Interventions targeted to increase commitment among specific donor groups should be tested further. PMID:23522891

Characteristics of donors who do or do not return to give blood and barriers to their return.

PubMed

Wevers, Anne; Wigboldus, Daniël H J; de Kort, Wim L A M; van Baaren, Rick; Veldhuizen, Ingrid J T

2014-01-01

In the Netherlands about 50% of whole blood donors return to give blood after an invitation to donate. This study aimed to investigate the characteristics of donor return behaviour and to gain insight into the barriers to blood donation reported by the donors themselves. A total of 4,901 whole blood donors were invited to donate in week 39 of 2009. Barriers mentioned by donors who informed the blood bank for not donating were registered for 1 month. Logistic regression analyses assessed relevant characteristics of return behaviour, such as age and blood type, in men and women separately. Of the invited donors, 55% returned to give a donation, whereas 45% did not return. Male donors were more likely to return when they were older, had a higher previous return rate and had no past deferrals. The same pattern was found among women, but was less strong. The main barriers were: time constraints (35%), preference to postpone donation due to general physical problems although being eligible to donate (29%), and being ineligible to donate due to medical deferral criteria (9%). Specific donor characteristics are associated with return behaviour. Not donating due to time constraints could mean that donors do not feel the urgency of donating blood. Interventions targeted to increase commitment among specific donor groups should be tested further.

Literature overview highlights lack of paediatric donation protocols but identifies common themes that could guide their development.

PubMed

Vileito, A; Siebelink, M J; Verhagen, Aae

2018-05-01

Paediatric donation is a unique and extremely sensitive process that requires specific knowledge and competencies. Most countries use protocols for organ and tissue donation to ensure optimal care for the donor and family, but these mainly focus on adults. However, the donation process for children differs from adults in many ways. An overview of the literature was performed to identify protocols for the paediatric population. PubMed, Web of Science, EMBASE and the Internet were searched up to March 2016 for papers or other sources in English related to specific organ and tissue donation protocols for children and neonates. This comprised title, abstract and then full-text screening of relevant data. We included 12 papers and two electronic sources that were mainly from North America and Europe. Most discussed donations after cardiac death. The recurring themes included identifying potential donors, approaching parents, palliative care and collaboration with organ procurement organisations. Most papers called for paediatric donation policies to be standardised. Scientific publications in English on paediatric donation protocols are very scarce. No comprehensive paediatric donation protocol was found. We identified several recurring themes in the literature that could be used to develop such protocols. ©2018 The Authors. Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica.

Physician perceptions about living organ donation in patients with Amyotrophic Lateral Sclerosis.

PubMed

Ansari, S; Bromberg, M B; Gibson, S B

2017-09-01

Patients with Amyotrophic Lateral Sclerosis (ALS) have expressed desire to become living organ donors but are unable to do so with current organ donation policies. Our objective is to assess ALS patient's interest in organ donation, and perceived concerns of this practice by ALS neurologists. An electronic survey was administered to ALS neurologists across the United States regarding living organ donation in ALS patients prior to respiratory failure. 52 complete responses were received from 121 invites. 67% (35/52) of neurologists expressed no concerns about living organ donation in ALS patients, and 33% had concerns. The concerns related to respiratory failure, anesthesia exposure and renal dysfunction. With their concerns addressed, 71% of neurologists reported that they would endorse living organ donation. 49% of neurologists reported being asked by a patient for information regarding living organ donation. ALS neurologists felt that 22.8% of ALS patients (median 19%) would be interested in learning more about organ donation, while only 6% of neurologists broach this subject with their patients. Our results indicate that 1 in every 4 ALS patients may be interested in exploring options for living organ donation, and this topic is not routinely addressed by ALS clinics. These results indicate an unexplored area of patient interest. To honor a patient's wishes to donate, the transplant community will have to accommodate living organ donation from terminally ill patients, and address neurologist concerns. Such a practice could benefit two groups of patients. Copyright © 2017 Elsevier B.V. All rights reserved.

DFT-GGA errors in NO chemisorption energies on (111) transition metal surfaces

NASA Astrophysics Data System (ADS)

Huang, Xu; Mason, Sara E.

2014-03-01

We investigate whether well-known DFT-GGA errors in predicting the chemisorption energy (Echem) of CO on transition metal surfaces manifest in analogous NO chemisorption systems. While widely investigated in the case of CO/metal, analogous DFT-GGA errors have long been claimed to be absent in NO/metal chemisorption. Here, we provide theoretical evidence of systematic enhanced back-donation in NO/metal chemisorption at the DFT-GGA level. We use electronic structure analysis to show that the partially filled molecular NO 2π* orbital rehybridizes with the transition metal d-band to form new bonding and anti-bonding states. We relate the back-donation charge transfer associated with chemisorption to the promotion of an electron from the 5σ orbital to the 2π* orbital in the gas-phase NO G2Σ- ← X2Π excitation. We establish linear relationships between Echem and ΔEG ← X and formulate an Echem correction scheme in the style of Mason et al. [Physical Review B 69, 161401(R)]. We apply the NO Echem correction method to the (111) surfaces of Pt, Pd, Rh, and Ir, with NO chemisorption modeled at a coverage of 0.25 ML. We note that the slope of Echemvs. ΔEG ← X and the dipole moment depend strongly on adsorption site for each metal, and we construct an approximate correction scheme which we test using NO/Pt(100) chemisorption.

A study of planar anchor groups for graphene-based single-molecule electronics.

PubMed

Bailey, Steven; Visontai, David; Lambert, Colin J; Bryce, Martin R; Frampton, Harry; Chappell, David

2014-02-07

To identify families of stable planar anchor groups for use in single molecule electronics, we report detailed results for the binding energies of two families of anthracene and pyrene derivatives adsorbed onto graphene. We find that all the selected derivatives functionalized with either electron donating or electron accepting substituents bind more strongly to graphene than the parent non-functionalized anthracene or pyrene. The binding energy is sensitive to the detailed atomic alignment of substituent groups over the graphene substrate leading to larger than expected binding energies for -OH and -CN derivatives. Furthermore, the ordering of the binding energies within the anthracene and pyrene series does not simply follow the electron affinities of the substituents. Energy barriers to rotation or displacement on the graphene surface are much lower than binding energies for adsorption and therefore at room temperature, although the molecules are bound to the graphene, they are almost free to move along the graphene surface. Binding energies can be increased by incorporating electrically inert side chains and are sensitive to the conformation of such chains.

A study of planar anchor groups for graphene-based single-molecule electronics

NASA Astrophysics Data System (ADS)

Bailey, Steven; Visontai, David; Lambert, Colin J.; Bryce, Martin R.; Frampton, Harry; Chappell, David

2014-02-01

To identify families of stable planar anchor groups for use in single molecule electronics, we report detailed results for the binding energies of two families of anthracene and pyrene derivatives adsorbed onto graphene. We find that all the selected derivatives functionalized with either electron donating or electron accepting substituents bind more strongly to graphene than the parent non-functionalized anthracene or pyrene. The binding energy is sensitive to the detailed atomic alignment of substituent groups over the graphene substrate leading to larger than expected binding energies for -OH and -CN derivatives. Furthermore, the ordering of the binding energies within the anthracene and pyrene series does not simply follow the electron affinities of the substituents. Energy barriers to rotation or displacement on the graphene surface are much lower than binding energies for adsorption and therefore at room temperature, although the molecules are bound to the graphene, they are almost free to move along the graphene surface. Binding energies can be increased by incorporating electrically inert side chains and are sensitive to the conformation of such chains.

A comparison of the bonding in Cr(NO)4 and Ni(CO)4

NASA Technical Reports Server (NTRS)

Bauschlicher, C. W., Jr.; Siegbahn, P. E. M.

1986-01-01

The bonding in Cr(NO)4 is very ionic, with about 1.5 electrons donated from the Cr to the NO 2pi orbitals. There is also a NO sigma donation of about 0.5 electrons to the Cr, yielding a net charge of Cr of about 1. A large MCSCF expansion is needed to describe both the ionic and covalent contributions to the Cr 3d-NO 2pi bonding. This bonding is compared to that in the isoelectronic Ni(CO)4.

2016 America's Recycle Day

NASA Image and Video Library

2016-11-15

Computers, monitors, vacuum cleaners and other electronics have been donated by employees at NASA's Kennedy Space Center in Florida in conjunction with America Recycles Day. America Recycles Day is a nationally recognized initiative dedicated to promoting recycling in the United States. Kennedy partnered with several organizations in order to donate as many of the items as possible to those who could use them the most in the Space Coast community. Space center personnel brought in electronic waste, gently used household goods, clothing and more. The two-day event was sponsored by Kennedy's Sustainability team.

Blood hero: An application for encouraging the blood donation by applying gamification.

PubMed

Domingos, Daniela C L; Lima, Luis F S G; Messias, Thiago F; Feijo, Jose V L; Diniz, Anthony A R; Soares, Heliana B

2016-08-01

There is a strong need for actions to supply the blood demand in the World. Based on this fact, it was designed an application, named `Blood Hero', by applying the `gamification' concept, which allows users to be rewarded by social acts related to the blood donation. It takes advantage of the application of mobile devices, implementing a specific social network, to attract and retain blood donators. This application makes possible an interaction between users and blood centers, and is being tested aiming at evaluating its acceptance and impact in bloodstocks.

The electron donating capacity of biochar is dramatically underestimated

PubMed Central

Prévoteau, Antonin; Ronsse, Frederik; Cid, Inés; Boeckx, Pascal; Rabaey, Korneel

2016-01-01

Biochars have gathered considerable interest for agronomic and engineering applications. In addition to their high sorption ability, biochars have been shown to accept or donate considerable amounts of electrons to/from their environment via abiotic or microbial processes. Here, we measured the electron accepting (EAC) and electron donating (EDC) capacities of wood-based biochars pyrolyzed at three different highest treatment temperatures (HTTs: 400, 500, 600 °C) via hydrodynamic electrochemical techniques using a rotating disc electrode. EACs and EDCs varied with HTT in accordance with a previous report with a maximal EAC at 500 °C (0.4 mmol(e−).gchar−1) and a large decrease of EDC with HTT. However, while we monitored similar EAC values than in the preceding study, we show that the EDCs have been underestimated by at least 1 order of magnitude, up to 7 mmol(e−).gchar−1 for a HTT of 400 °C. We attribute this existing underestimation to unnoticed slow kinetics of electron transfer from biochars to the dissolved redox mediators used in the monitoring. The EDC of other soil organic constituents such as humic substances may also have been underestimated. These results imply that the redox properties of biochars may have a much bigger impact on soil biogeochemical processes than previously conjectured. PMID:27628746

IR and TPD studies of the interaction of alkenes with Cu + sites in CuNaY and CuNaX zeolites of various Cu content. The heterogeneity of Cu + sites

NASA Astrophysics Data System (ADS)

Datka, J.; Kukulska-Zajaç, E.; Kozyra, P.

2006-08-01

Cu + ions in zeolites activate organic molecules containing π electrons by π back donation, which results in a distinct weakening of multiple bonds. In this study, we followed the activation of alkenes (ethene and propene) by Cu + ions in CuY and CuX zeolites of various Cu content. We also studied the strength of bonding of alkenes to Cu + ions. IR studies have shown that there are two kinds of Cu + sites of various electron donor properties. We suppose that they could be attributed to the presence of Cu + ions of various number of oxygen atoms surrounding the cation. IR studies have shown that Cu ions introduced into Y and X zeolites in the first-order (at low Cu content) form Cu + ions of stronger electron donor properties (i.e. activate alkenes to larger extend) than Cu ions introduced in the next order (at higher Cu content). IR and TPD studies of alkenes desorption evidenced that Cu + ions of stronger electron donor properties bond alkenes stronger than less electron donor ones. It suggests that π back donation has more important contribution to the strength of bonding alkenes to cation than π donation.

Mechanistic details for cobalt catalyzed photochemical hydrogen production in aqueous solution: Efficiencies of the photochemical and non-photochemical steps

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

Shan, Bing; Baine, Teera; Ma, Xuan Anh N.

2013-04-17

The use of sunlight to drive chemical reactions that lead to the reduction of water to produce hydrogen is a potential avenue of solar energy utilization. There are many individual steps that take place in this process. This paper reports the investigation of a particular system that involves light absorbing molecules, electron donating agents and a catalyst for water reduction to hydrogen. We evaluated the efficiency of the light induced formation of a strong electron donor, the use of this donor to reduce the catalyst and finally the efficiency of the catalyst to produce hydrogen from water. From this, themore » sources of loss of efficiency could be clearly identified and used in the design of better systems to produce hydrogen from water.« less

Two-photon or higher-order absorbing optical materials for generation of reactive species

NASA Technical Reports Server (NTRS)

Marder, Seth R. (Inventor); Cumpston, Brian (Inventor); Lipson, Matthew (Inventor); Perry, Joseph W. (Inventor)

2003-01-01

Disclosed are highly efficient multiphoton absorbing compounds and methods of their use. The compounds generally include a bridge of pi-conjugated bonds connecting electron donating groups or electron accepting groups. The bridge may be substituted with a variety of substituents as well. Solubility, lipophilicity, absorption maxima and other characteristics of the compounds may be tailored by changing the electron donating groups or electron accepting groups, the substituents attached to or the length of the pi-conjugated bridge. Numerous photophysical and photochemical methods are enabled by converting these compounds to electronically excited states upon simultaneous absorption of at least two photons of radiation. The compounds have large two-photon or higher-order absorptivities such that upon absorption, one or more Lewis acidic species, Lewis basic species, radical species or ionic species are formed.

Two-photon or higher-order absorbing optical materials for generation of reactive species

NASA Technical Reports Server (NTRS)

Perry, Joseph W (Inventor); Cumpston, Brian (Inventor); Lipson, Matthew (Inventor); Marder, Seth R (Inventor)

2007-01-01

Disclosed are highly efficient multiphoton absorbing compounds and methods of their use. The compounds generally include a bridge of pi-conjugated bonds connecting electron donating groups or electron accepting groups. The bridge may be substituted with a variety of substituents as well. Solubility, lipophilicity, absorption maxima and other characteristics of the compounds may be tailored by changing the electron donating groups or electron accepting groups, the substituents attached to or the length of the pi-conjugated bridge. Numerous photophysical and photochemical methods are enabled by converting these compounds to electronically excited states upon simultaneous absorption of at least two photons of radiation. The compounds have large two-photon or higher-order absorptivities such that upon absorption, one or more Lewis acidic species, Lewis basic species, radical species or ionic species are formed.

Two-Photon or Higher-Order Absorbing Optical Materials for Generation of Reactive Species

NASA Technical Reports Server (NTRS)

Perry, Joseph W. (Inventor); Cumpston, Brian (Inventor); Lipson, Matthew (Inventor); Marder, Seth R. (Inventor)

2013-01-01

Disclosed are highly efficient multiphoton absorbing compounds and methods of their use. The compounds generally include a bridge of pi-conjugated bonds connecting electron donating groups or electron accepting groups. The bridge may be substituted with a variety of substituents as well. Solubility, lipophilicity, absorption maxima and other characteristics of the compounds may be tailored by changing the electron donating groups or electron accepting groups, the substituents attached to or the length of the pi-conjugated bridge. Numerous photophysical and photochemical methods are enabled by converting these compounds to electronically excited states upon simultaneous absorption of at least two photons of radiation. The compounds have large two-photon or higher-order absorptivities such that upon absorption, one or more Lewis acidic species, Lewis basic species, radical species or ionic species are formed.

Occurrence and removal of pharmaceuticals, hormones, personal care products, and endocrine disrupters in a full-scale water reclamation plant.

PubMed

Tran, Ngoc Han; Gin, Karina Yew-Hoong

2017-12-01

This study provided the first comprehensive data on the occurrence and removal of twenty-five target emerging contaminants (ECs) in a full-scale water reclamation plant (WRP) in the Southeast Asian region. Nineteen out of the twenty-five ECs were ubiquitously detected in raw influent samples. Concentrations of the detected ECs in raw influent samples ranged substantially from 44.3 to 124,966ng/L, depending upon the compound and sampling date. The elimination of ECs in full-scale conventional activated sludge (CAS) and membrane bioreactor (MBR) systems at a local WRP was evaluated and compared. Several ECs, such as acetaminophen, atenolol, fenoprofen, indomethacin, ibuprofen, and oxybenzone, exhibited excellent removal efficiencies (>90%) in biological wastewater treatment processes, while some of the investigated compounds (carbamazepine, crotamiton, diclofenac, and iopamidol) appeared to be persistent in the both CAS and MBR systems. Field-based monitoring results showed that MBR outperformed CAS in the elimination of most target ECs. The relationship between molecular characteristics of ECs (i.e. physicochemical properties and structural features) and their removal efficiencies during biological wastewater treatment was also elucidated. Excellent removal efficiencies (>90%) were often noted for ECs with the sole presence of electron donating groups (i.e. phenolic [OH], amine [NH 2 ], methoxy [OCH 3 ], phenoxy [OC 6 H 5 ], or alkyl groups). Conversely, ECs with the absence of electron donating groups or the predominance of strong electron withdrawing groups (e.g. halogenated, carbonyl, carboxyl, and sulfonamide) tended to show poor removal efficiencies (<30%) in biological wastewater treatment processes. Copyright © 2017 Elsevier B.V. All rights reserved.

Biocatalytic degradation of pharmaceuticals, personal care products, industrial chemicals, steroid hormones and pesticides in a membrane distillation-enzymatic bioreactor.

PubMed

Asif, Muhammad B; Hai, Faisal I; Kang, Jinguo; van de Merwe, Jason P; Leusch, Frederic D L; Price, William E; Nghiem, Long D

2018-01-01

Laccase-catalyzed degradation of a broad spectrum of trace organic contaminants (TrOCs) by a membrane distillation (MD)-enzymatic membrane bioreactor (EMBR) was investigated. The MD component effectively retained TrOCs (94-99%) in the EMBR, facilitating their continuous biocatalytic degradation. Notably, the extent of TrOC degradation was strongly influenced by their molecular properties. A significant degradation (above 90%) of TrOCs containing strong electron donating functional groups (e.g., hydroxyl and amine groups) was achieved, while a moderate removal was observed for TrOCs containing electron withdrawing functional groups (e.g., amide and halogen groups). Separate addition of two redox-mediators, namely syringaldehyde and violuric acid, further improved TrOC degradation by laccase. However, a mixture of both showed a reduced performance for a few pharmaceuticals such as primidone, carbamazepine and ibuprofen. Mediator addition increased the toxicity of the media in the enzymatic bioreactor, but the membrane permeate (i.e., final effluent) was non-toxic, suggesting an added advantage of coupling MD with EMBR. Copyright © 2017 Elsevier Ltd. All rights reserved.

African Americans' knowledge about organ donation: closing the gap with more effective persuasive message strategies.

PubMed

Morgan, Susan E; Cannon, Thomas

2003-11-01

In spite of increasing interest in the area of African Americans' willingness to donate organs, little empirical knowledge exists that can be used to create more effective public communication campaigns. In this study, 310 African Americans responded to seven knowledge items (based on myths and misconceptions about organ donation) shown in past studies to discriminate between donors and nondonors. The rate of accurate responses varied from 33% to 78% to individual knowledge items. Beliefs that the organ allocation system is inequitable (favoring whites and the rich) and the belief that donors pay extra medical bills strongly distinguished donors from nondonors. In addition, the information sources reported by African Americans willing to donate were more likely to include family members. Implications of these findings to the development of more effective organ donation campaigns targeting African Americans are offered.

On the bonding mechanism of CO to Pt(111) and its effect on the vibrational frequency of chemisorbed CO

NASA Astrophysics Data System (ADS)

Illas, F.; Zurita, S.; Márquez, A. M.; Rubio, J.

1997-04-01

The chemisorption of CO on the atop site of Pt(111) has been simulated by a Pt4 cluster model. Ab initio self consistent field (SCF) and complete active space self consistent field (CASSCF) cluster model wave functions have been obtained for the electronic ground state. Likewise, ab initio SCF wavefunctions have been obtained for two other electronic states. The optimum geometry and vibrational frequencies of chemisorbed CO are reported for the three states. The interaction energy and vibrational shift of chemisorbed CO, with respect to free gas phase CO, have been analyzed for the three electronic states. This analysis is carried out by means of the constrained space orbital variation (CSOV) method. In all cases the bond is found to be dominated by σ donation and π back-donation, known as Blyholder's mechanism. This mechanism is further supported by SCF calculations on a larger, Pt13, cluster model. For both clusters, the CSOV analysis of the vibrational frequency definitely shows that, contrary to previous recent studies, a major contribution to the experimentally observed vibrational shift comes from the π back-donation mechanism. However, we found that, contrary to common belief, σ donation also acts to lower the CO frequency and not to increase it. Physical reasons for such unexpected behaviour are given.

The role of women in the donation consent decision: building on previous research.

PubMed

Dodd-McCue, Diane; Tartaglia, Alexander; Cowherd, Robin

2007-09-01

Recently published findings emphasize the dominant role of women in the donation discussion. With some noteworthy exceptions, the empirical literature on gender and donation, and the role of gender in healthcare decisions as well as donation, is limited. To provide preliminary information needed to begin theoretical or framework development and to initiate more rigorous research on the role of gender in donation discussions. This exploratory study is a descriptive qualitative retrospective study using focus group methodology. Two focus groups were conducted in 2 major cities in the organ procurement organization's service area. Participants were women who were involved in the donation discussion within the past 5 years; 6 participated in 1 session, 8 in the other. The focus group discussions highlight the role of women in the donation process relative to information needs, information usage, and the ensuring dynamics of the donation discussion. Compared to men, women tend to seek more information and reframe this information for others. Because women are frequently central in family communication networks, they serve as a communication conduit for other family members and may influence others. Involving key women decision makers in the early stages of the donation discussion and providing information elaboration build on women's central placement and role in family communication network processes. The significance of women's central placement may carry cultural implications, particularly for racial or ethnic groups with strong matriarchal or extended kinship structures.

role of altruistic behavior, empathetic concern, and social responsibility motivation in blood donation behavior.

PubMed

Steele, Whitney Randolph; Schreiber, George B; Guiltinan, Anne; Nass, Catharie; Glynn, Simone A; Wright, David J; Kessler, Debra; Schlumpf, Karen S; Tu, Yongling; Smith, James W; Garratty, George

2008-01-01

Blood donation can be described as a prosocial behavior, and donors often cite prosocial reasons such as altruism, empathy, or social responsibility for their willingness to donate. Previous studies have not quantitatively evaluated these characteristics in donors or examined how they relate to donation frequency. As part of a donor motivation study, 12,064 current and lapsed donors answered questions used to create an altruistic behavior, empathetic concern, and social responsibility motivation score for each donor. Analysis of variance was used to compare mean scores by demographics and donor status and to determine the influence of each variable on the mean number of donations in the past 5 years. The mean score for each prosocial characteristic appeared high, with lower scores in male and younger donors. Higher altruistic behavior and social responsibility motivation scores were associated with increased past donation frequency, but the effects were minor. Empathetic concern was not associated with prior donation. The largest differences in prior donations were by age and donor status, with older and current donors having given more frequently. Most blood donors appear to have high levels of the primary prosocial characteristics (altruism, empathy, and social responsibility) commonly thought to be the main motivators for donation, but these factors do not appear to be the ones most strongly related to donation frequency. Traditional donor appeals based on these characteristics may need to be supplemented by approaches that address practical concerns like convenience, community safety, or personal benefit.

Attitudes of intensive care and emergency physicians in Australia with regard to the organ donation process: A qualitative analysis.

PubMed

Macvean, Emily; Yuen, Eva Yn; Tooley, Gregory; Gardiner, Heather M; Knight, Tess

2018-04-01

Specialized hospital physicians have direct capacity to impact Australia's sub-optimal organ donation rates because of their responsibility to identify and facilitate donation opportunities. Australian physicians' attitudes toward this responsibility are examined. A total of 12 intensive care unit and three emergency department physicians were interviewed using a constructionist grounded theory and situational analysis approach. A major theme emerged, related to physicians' conflicts of interest in maintaining patients'/next-of-kin's best interests and a sense of duty-of-care in this context. Two sub-themes related to this main theme were identified as follows: (1) discussions about organ donation and who is best to carry these out and (2) determining whether organ donation is part of end-of-life care; including the avoidance of non-therapeutic ventilation; and some reluctance to follow clinical triggers in the emergency department. Overall, participants indicated strong support for organ donation but would not consider it part of end-of-life care, representing a major obstacle to the support of potential donation opportunities. Findings have implications for physician education and training. Continued efforts are needed to integrate the potential for organ donation into end-of-life care within intensive care units and emergency departments.

Attitudes of Australian chiropractic students toward whole body donation: a cross-sectional study.

PubMed

Alexander, Michelle; Marten, Mathew; Stewart, Ella; Serafin, Stanley; Štrkalj, Goran

2014-01-01

Cadavers play an important role in anatomy education. In Australia, bodies for anatomy education are acquired only through donations. To gain insight into educational dynamics in an anatomy laboratory as well as to facilitate body donation programs and thanksgiving ceremonies, it is important to understand students' attitudes toward body donation. In this cross-sectional study, the attitudes of Macquarie University's first, second, and fifth year chiropractic students toward body donation were investigated. Macquarie University chiropractic students have a four semester long anatomy program, which includes cadaver-based instruction on prosected specimens. A questionnaire was used to record respondents' demographics and attitudes toward body donation: personal, by a relative, and by a stranger. It was found that ethnicity and religion affect attitudes toward body donation, with Australian students being more willing to donate a stranger's body and atheists and agnostics being more willing to donate in general. Furthermore, willingness to donate one's own or a family member's body decreases as year of study increases, suggesting a possible negative impact of exposure to cadavers in the anatomy laboratory. This was only true, however, after controlling for age. Thus, the impact of viewing and handling prosected specimens, which is the norm in anatomy classes in Australia, may not be as strong as dissecting cadavers. It is suggested that anatomists and educators prepare students for cadaver-based instruction as well as exhibit sensitivity to cultural differences in how students approach working with cadavers, when informing different communities about body donation programs and in devising thanksgiving ceremonies. © 2013 American Association of Anatomists.

Views and attitudes towards blood donation: a qualitative investigation of Indian non-donors living in England

PubMed Central

Joshi, Dhaara; Meakin, Richard

2017-01-01

Objective To explore the views and attitudes of Indians living in England on blood donation. Background In light of the predicted shortages in blood supply, it is vital to consider ways in which to maximise donation rates. These include addressing the issue of lower donation rates among ethnic minorities, including Indians. However research specifically among minority ethnicities in UK is sparse. Setting General practice in North London. Participants A convenience sample of 12 non-donor Indians living in England. Methods This is a qualitative investigation involving semistructured interviews. Themes derived were analysed using thematic framework analysis. Results Five key themes emerged from the data, and these concerned participants’ perspectives regarding attitudes towards blood, blood donation as a ‘good thing’, donation disincentives, the recipient matters and the donor matters. Conclusion A variety of attitudes were presented, but were generally positive, and blood was conceptualised in a manner previously found to be consistent with donation. However, lack of awareness and accessibility were prominent barriers, indicating the need for improvement in these capacities. In contrast to this, blood was also greatly associated with family and acted as a symbol of kinship: this ‘emotional charge’ often acted to dissuade participants from separating with their blood through donation. Possibly due to this, there was also a strong preference for donated blood to be distributed within the family, as opposed to strangers. This presents a potential barrier to blood donation for some Indians within the current system in which donations are given to unknown recipients. PMID:29061628

Lateral cis-1,3,5,7-tetraazadecalin podands and their complexes: synthesis, structure, and strong binding with Pb(II) and other heavy metal ions.

PubMed

Reany, Ofer; Fuchs, Benzion

2013-02-18

The chemistry and complexation behavior of diaminal podands based on cis-1,3,5,7-tetraazadecalin (cis-TAD) were elaborated, reassessed, and extended. The synthesis of 2,6-bis(hydroxymethylene)-cis-TAD (9) and 2,6-bis(α,α'-dimethyl-β- hydroxyethyl)-cis-TAD (10) as well as of suitably substituted 2,6-diaryl-cis-TAD podands is laid out. For the latter, the effect of electron donating or withdrawing substituents on the benzaldehyde reagents was examined while 9 and 10 were probed and showed considerable propensity for heavy metal-ion chelation. The [Cd(II)·(9)] and [Pb(II)·(9)] complexes stood out indeed, and their structure and properties show a particularly interesting 5-amino-1,3-diazane chelation type and strong ligand-ion binding mode, with intramolecular donor exchange in solution, all strongly influenced by the anomeric effect in the ligand.

Electron transfer properties of peat organic matter: from electrochemical analysis to redox processes in peatlands

NASA Astrophysics Data System (ADS)

Sander, Michael; Getzinger, Gordon; Walpen, Nicolas

2017-04-01

Peat organic matter contains redox-active functional groups that can accept and/or donate electrons from and to biotic and abiotic reaction partners present in peatlands. Several studies have provided evidence that electron accepting quinone moieties in the peat organic matter may act as terminal electron acceptors for anaerobic microbial respiration. This respiration pathway may competitively suppress methanogenesis and thereby lead to excess carbon dioxide to methane formation in peatlands. Electron donating phenolic moieties in peat organic matter have long been considered to inhibit microbial and enzymatic activities in peatlands, thereby contributing to carbon stabilization and accumulation in these systems. Phenols are expected to be comparatively stable in anoxic parts of the peats as phenoloxidases, a class of enzymes capable of oxidatively degrading phenols, require molecular oxygen as co-substrate. Despite the general recognition of the importance of redox-active moieties in peat organic matter, the abundance, redox properties and reactivities of these moieties remain poorly studied and understood, in large part due to analytical challenges. This contribution will, in a first part, summarize recent advances in our research group on the analytical chemistry of redox-active moieties in peat organic matter. We will show how mediated electrochemical analysis can be used to quantify the capacities of electron accepting and donating moieties in both dissolved and particulate peat organic matter. We will link these capacities to the physicochemical properties of peat organic matter and provide evidence for quinones and phenols as major electron accepting and donating moieties, respectively. The second part of this contribution will highlight how these electroanalytical techniques can be utilized to advance a more fundamental understanding of electron transfer processes involving peat organic matter. These processes include the redox cycling (i.e., repeated reduction and re-oxidation) of peat organic matter under alternating anoxic-oxic conditions as well as the oxidation of phenolic moieties in peat organic matter by phenol oxidases in the presence of molecular oxygen. Overall, this contribution will attempt to link molecular-level insights into the redox properties of peat organic matter to larger scale redox processes that are important to carbon cycling in peatlands.

Long-range coupling of electron-hole pairs in spatially separated organic donor-acceptor layers

PubMed Central

Nakanotani, Hajime; Furukawa, Taro; Morimoto, Kei; Adachi, Chihaya

2016-01-01

Understanding exciton behavior in organic semiconductor molecules is crucial for the development of organic semiconductor-based excitonic devices such as organic light-emitting diodes and organic solar cells, and the tightly bound electron-hole pair forming an exciton is normally assumed to be localized on an organic semiconducting molecule. We report the observation of long-range coupling of electron-hole pairs in spatially separated electron-donating and electron-accepting molecules across a 10-nanometers-thick spacer layer. We found that the exciton energy can be tuned over 100 megaelectron volts and the fraction of delayed fluorescence can be increased by adjusting the spacer-layer thickness. Furthermore, increasing the spacer-layer thickness produced an organic light-emitting diode with an electroluminescence efficiency nearly eight times higher than that of a device without a spacer layer. Our results demonstrate the first example of a long-range coupled charge-transfer state between electron-donating and electron-accepting molecules in a working device. PMID:26933691

Synthesis and Photoluminescent Properties of Arylethynyl substituted 9,10-Anthraquinones

NASA Technical Reports Server (NTRS)

Yang, Jin-Hua; Dass, Amala; Sotiriou-Leventis, Chariklia; Leventis, Nicholas

2003-01-01

A series of arylethynyl substituted anthraquinones were synthesized via Sonogashira coupling reactions of 2,7- dibromo-, 2,6-dibromo- and 2-bromoanthraquinone with para-substituted phenylacetylenes. While the redox properties of those compounds are almost insensitive to substitution, their absorption maxima are linearly related to the Hammett constants for electron donating and electron withdrawing groups separately. All compounds are photoluminescent both in solution (quantum yield of emission approximately 2%) and as solids. X-ray crystallographic characterization of 2,7-bisphenylethynyl anthraquinone indicates a monoclinic p2(l/n) space group and no indication for pi-overlap that would promote self-quenching. The emission maxima are red- shifted by both electron donating and electron withdrawing groups alike. The Stokes shifts of all compounds are significant and are correlated to the electronic properties of the substituents. The reduced forms of these compounds are also photoluminescent and the emission originates from the dihydroanthraquinone core.

Uranium(III)-carbon multiple bonding supported by arene δ-bonding in mixed-valence hexauranium nanometre-scale rings.

PubMed

Wooles, Ashley J; Mills, David P; Tuna, Floriana; McInnes, Eric J L; Law, Gareth T W; Fuller, Adam J; Kremer, Felipe; Ridgway, Mark; Lewis, William; Gagliardi, Laura; Vlaisavljevich, Bess; Liddle, Stephen T

2018-05-29

Despite the fact that non-aqueous uranium chemistry is over 60 years old, most polarised-covalent uranium-element multiple bonds involve formal uranium oxidation states IV, V, and VI. The paucity of uranium(III) congeners is because, in common with metal-ligand multiple bonding generally, such linkages involve strongly donating, charge-loaded ligands that bind best to electron-poor metals and inherently promote disproportionation of uranium(III). Here, we report the synthesis of hexauranium-methanediide nanometre-scale rings. Combined experimental and computational studies suggest overall the presence of formal uranium(III) and (IV) ions, though electron delocalisation in this Kramers system cannot be definitively ruled out, and the resulting polarised-covalent U = C bonds are supported by iodide and δ-bonded arene bridges. The arenes provide reservoirs that accommodate charge, thus avoiding inter-electronic repulsion that would destabilise these low oxidation state metal-ligand multiple bonds. Using arenes as electronic buffers could constitute a general synthetic strategy by which to stabilise otherwise inherently unstable metal-ligand linkages.

Design, Synthesis, Structural and Spectroscopic Studies of Push-Pull Two-Photon Absorbing Chromophores with Acceptor Groups of Varying Strength

PubMed Central

Morales, Alma R.; Frazer, Andrew; Woodward, Adam W.; Ahn-White, Hyo-Yang; Fonari, Alexandr; Tongwa, Paul; Timofeeva, Tatiana; Belfield, Kevin D.

2013-01-01

A new series of unsymmetrical diphenylaminofluorene-based chromophores with various strong π-electron acceptors were synthesized and fully characterized. The systematic alteration of the structural design facilitated the investigation of effects such as molecular symmetry and strength of electron-donating and/or withdrawing termini have on optical nonlinearity. In order to determine the electronic and geometrical properties of the novel compounds, a thorough investigation was carried out by a combination of linear and nonlinear spectroscopic techniques, single crystal X-ray diffraction, and quantum chemical calculations. Finally, on the basis of two-photon absorption (2PA) cross sections, the general trend for π -electron accepting ability, i.e., ability to accept charge transfer from diphenylamine was: 2-pyran-4-ylidene malononitrile (pyranone) > dicyanovinyl > bis(dicyanomethylidene)indane > 1-(thiophen-2-yl)propenone > dicyanoethylenyl > 3-(thiophen-2-yl)propenone. An analog with the 2-pyran-4-ylidene malononitrile acceptor group exhibited a nearly three-fold enhancement of the 2PA< δ (1650 GM at 840 nm), relative to other members of the series. PMID:23305555

Hyperpolarizable compounds and devices fabricated therefrom

DOEpatents

Therien, Michael J.; DiMagno, Stephen G.

1998-01-01

Substituted compounds having relatively large molecular first order hyperpolarizabilities are provided, along with devices and materials containing them. In general, the compounds bear electron-donating and electron-withdrawing chemical substituents on a polyheterocyclic core.

Theoretical study of structure, bonding, and electronic behavior of novel sandwich compounds M₃(C6R6)₂ (M = Ni, Pd, Pt; R = H, F).

PubMed

Zhou, Ke

2012-10-01

The correlations between the structural and electronic properties of the monolayer clusters M₃ (where M = Ni, Pd, Pt) and the sandwich complexes M₃(C₆R₆)₂ (where M = Ni, Pd, Pt; R = H, F) were studied by performing quantum-chemical calculations. All of the sandwich complexes are strongly donating and backdonating metal-ligand bonding structures. The influence of the ligand as well as significant variations in the M-C, M-M, and C-C bond lengths and binding energies were examined to obtain a qualitative and quantitative picture of the intramolecular interactions in C₆R₆-M₃. Our theoretical investigations show that the binding energies of these sandwich complexes gradually decrease from Ni to Pt as well as from H to F, which can be explained via the frontier orbitals of the clusters M₃ and C₆R₆.

Coordination Chemistry of a Strongly-Donating Hydroxylamine with Early Actinides: An Investigation of Redox Properties and Electronic Structure

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

McSkimming, Alex; Su, Jing; Cheisson, Thibault

Separations of f-block elements are a critical aspect of nuclear waste processing. Redox-based separations offer promise, but challenges remain in stabilizing and differentiating actinides in high oxidation states. The investigation of new ligand types that provide thermodynamic stabilization to high-valent actinides is essential for expanding their fundamental chemistry and to elaborate new separation techniques and storage methods. We report herein the preparation and characterization of Th and U complexes of the pyridyl-hydroxylamine ligand, N-tert-butyl-N-(pyridin-2-yl)hydroxylamine (pyNO–). Electrochemical studies performed on the homoleptic complexes [M(pyNO) 4] (M = Th, U) revealed significant stabilization of the U complex upon one-electron oxidation. The saltmore » [U(pyNO) 4] + was isolated by chemical oxidation of [U(pyNO) 4]; spectroscopic and computational data support assignment as a U V cation.« less

Coordination Chemistry of a Strongly-Donating Hydroxylamine with Early Actinides: An Investigation of Redox Properties and Electronic Structure

DOE PAGES

McSkimming, Alex; Su, Jing; Cheisson, Thibault; ...

2018-03-23

Separations of f-block elements are a critical aspect of nuclear waste processing. Redox-based separations offer promise, but challenges remain in stabilizing and differentiating actinides in high oxidation states. The investigation of new ligand types that provide thermodynamic stabilization to high-valent actinides is essential for expanding their fundamental chemistry and to elaborate new separation techniques and storage methods. We report herein the preparation and characterization of Th and U complexes of the pyridyl-hydroxylamine ligand, N-tert-butyl-N-(pyridin-2-yl)hydroxylamine (pyNO–). Electrochemical studies performed on the homoleptic complexes [M(pyNO) 4] (M = Th, U) revealed significant stabilization of the U complex upon one-electron oxidation. The saltmore » [U(pyNO) 4] + was isolated by chemical oxidation of [U(pyNO) 4]; spectroscopic and computational data support assignment as a U V cation.« less

Knowledge and Attitudes Toward Organ Donation in Health Care Undergraduate Students in Italy.

PubMed

Fontana, F; Massari, M; Giovannini, L; Alfano, G; Cappelli, G

2017-11-01

The number of organ donors in Italy is increasing, but with still disappointing living donation activity and relatively frequent objection by potential deceased donors' relatives to organ recovery. Few studies have assessed health care students' knowledge and attitude on donation. We administered a questionnaire to medical (MS) and nursing students (NS) at University of Modena and Reggio Emilia, Italy, and 749 students (406 MS and 343 NS) completed the questionnaire. Although 95% of students were in favor of donation, only 21.9% of NS and 24.9% of MS were registered as donors. One quarter of students reported family disagreement. MS appeared more confident with personnel involved in donation. Overall, 60% of students knew the term donation after brain death but only 40% were aware of the criteria used to define it. Barely 27.1% of NS and 15.3% of MS believed they had received sufficient information in lessons. Backward logistic regression demonstrated that students whose families agree with them and who knew the definition of donation after brain death were more likely to express the disposition of registering, and those who showed distrust in the declaration of brain death were half as likely to register as donors. Students expressed a lack of knowledge, controversial attitudes on donation, and strong need for education; increased awareness may help increase donation rates. The majority of educational institutions in Italy do not directly address training on organ donation and transplantation for health care students; an integrated curriculum favoring interpersonal discussion including practical aspects is urgently required. Copyright © 2017 Elsevier Inc. All rights reserved.

Stress influences environmental donation behavior in men.

PubMed

Sollberger, Silja; Bernauer, Thomas; Ehlert, Ulrike

2016-01-01

Stress has been found to have both positive and negative effects on prosocial behavior, suggesting the involvement of moderating factors such as context and underlying motives. In the present study, we investigated the conditions under which acute stress leads to an increase vs. decrease in environmental donation behavior as an indicator of prosocial behavior. In particular, we examined whether the effects of stress depended on preexisting pro-environmental orientation and stage of the donation decision (whether or not to donate vs. the amount to be donated). Male participants with either high (N=40) or low (N=39) pro-environmental orientation were randomly assigned to a social stress test or a control condition. Salivary cortisol was assessed repeatedly before and after stress induction. At the end of the experiment, all subjects were presented with an opportunity to donate a portion of their monetary compensation to a climate protection foundation. We found that stress significantly increased donation frequency, but only in subjects with low pro-environmental orientation. Congruously, their decision to donate was positively associated with cortisol response to the stress test and the emotion regulation strategy mood repair, as well as accompanied by an increase in subjective calmness. In contrast, among the participants who decided to donate, stress significantly reduced the donated amount of money, regardless of pro-environmental orientation. In conclusion, our findings suggest that acute stress might generally activate more self-serving motivations, such as making oneself feel better and securing one's own material interests. Importantly, however, a strong pro-environmental orientation partially prevented these effects. Copyright © 2015 Elsevier Ltd. All rights reserved.

Views and attitudes towards blood donation: a qualitative investigation of Indian non-donors living in England.

PubMed

Joshi, Dhaara; Meakin, Richard

2017-10-22

To explore the views and attitudes of Indians living in England on blood donation. In light of the predicted shortages in blood supply, it is vital to consider ways in which to maximise donation rates. These include addressing the issue of lower donation rates among ethnic minorities, including Indians. However research specifically among minority ethnicities in UK is sparse. General practice in North London. A convenience sample of 12 non-donor Indians living in England. This is a qualitative investigation involving semistructured interviews. Themes derived were analysed using thematic framework analysis. Five key themes emerged from the data, and these concerned participants' perspectives regarding attitudes towards blood, blood donation as a 'good thing', donation disincentives, the recipient matters and the donor matters. A variety of attitudes were presented, but were generally positive, and blood was conceptualised in a manner previously found to be consistent with donation. However, lack of awareness and accessibility were prominent barriers, indicating the need for improvement in these capacities. In contrast to this, blood was also greatly associated with family and acted as a symbol of kinship: this 'emotional charge' often acted to dissuade participants from separating with their blood through donation. Possibly due to this, there was also a strong preference for donated blood to be distributed within the family, as opposed to strangers. This presents a potential barrier to blood donation for some Indians within the current system in which donations are given to unknown recipients. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Blood donation history and eligibility assessment in a community-based sample of men who have sex with men.

PubMed

Custer, Brian; Murcia, Karla; Robinson, William T; McFarland, Willi; Raymond, Henry Fisher

2018-04-01

In 2016, the US Food and Drug Administration changed the regulation from a permanent deferral from donation for men who have sex with men (MSM) to a 1-year deferral since last sexual contact. It is unknown what proportions of MSM try to donate and if they would be willing to answer individual risk-based questions to assess their current eligibility. The National HIV Behavioral Surveillance surveys periodically measure human immunodeficiency virus (HIV) prevalence and risk behaviors among MSM using a venue-based, time-location sampling method. In the 2014 cycle, that is, before the policy change, investigators in San Francisco and New Orleans added questions about blood donation. Questions inquired into three domains: donation history, policy awareness, and knowledge about HIV testing of donations. There were 404 and 557 respondents in San Francisco and New Orleans, respectively. Nearly one in three MSM in San Francisco (27.4%) and New Orleans (31.4%) tried to donate after their first MSM contact. A majority (63.1% in San Francisco, 58.8% in New Orleans) somewhat or strongly agreed that they would be willing to be asked detailed questions for donation eligibility assessment. The proportion of MSM who reported trying to donate was similar in the two cities. However, a substantial proportion did not agree to be asked more detailed risk behavior questions to assess eligibility. In these two geographic locations, prominent regional differences were not evident. © 2018 AABB.

Giving Your Last Gift: A Study of the Knowledge, Attitude and Information of Greek Students Regarding Organ Donation.

PubMed

Katsari, Vasiliki; Domeyer, Philip J; Sarafis, Pavlos; Souliotis, Kyriakos

2015-07-02

Organ donation rates in Greece are the lowest in the European Union. Studying and improving young students' awareness may increase organ donation rates. This study aimed to investigate young students' knowledge, attitude and information regarding organ donation and whether they are modified by putative predictors. A 62-item electronic questionnaire was sent to 1451 eligible students aged 18-30 years in 16 Greek public technical schools. Two composite scales (knowledge and attitude) were created. The multivariate statistical analysis included ordinal logistic and linear regression, as appropriate. Only 37.9% of the students knew the correct definition of organ donation, 40.3% knew which organs can be donated, 27.4% were informed about the new Greek legislation, and 83.1% acknowledged the need for better information. Although 60.5% would donate an organ after death, only 16.1% would become living donors. Although 83.1% of the students declared knowing what brain death means, 18.6% believe that a brain-dead person could fully recover and 32.3% are unsure about it. Being a health professional or a blood donor, the parent's educational level, the wish to donate all organs after death, the information from announcements or posters, the fear of organ removal after death without prior consent, the consent for autopsy, the wish for better information, and the misbelief that a brain-dead person could fully recover emerged as important predictors of the knowledge and attitude, regarding organ donation. An important lack of knowledge and misperceptions were noted regarding organ donation. Significant predictors were identified.

CO 2 Hydrogenation Catalysts with Deprotonated Picolinamide Ligands

DOE PAGES

Kanega, Ryoichi; Onishi, Naoya; Szalda, David J.; ...

2017-08-21

In an effort to design concepts for highly active catalysts for the hydrogenation of CO 2 to formate in basic water, we have prepared in this paper several catalysts with picolinic acid, picolinamide, and its derivatives, and we investigated their catalytic activity. The CO 2 hydrogenation catalyst having a 4-hydroxy-N-methylpicolinamidate ligand exhibited excellent activity even under ambient conditions (0.1 MPa, 25 °C) in basic water, exhibiting a TON of 14700, a TOF of 167 h –1, and producing a 0.64 M formate concentration. Finally, its high catalytic activity originates from strong electron donation by the anionic amide moiety in additionmore » to the phenolic O – functionality.« less

Charge-transfer complexes and their role in exciplex emission and near-infrared photovoltaics.

PubMed

Ng, Tsz-Wai; Lo, Ming-Fai; Fung, Man-Keung; Zhang, Wen-Jun; Lee, Chun-Sing

2014-08-20

Charge transfer and interactions at organic heterojunctions (OHJs) are known to have critical influences on various properties of organic electronic devices. In this Research News article, a short review is given from the electronic viewpoint on how the local molecular interactions and interfacial energetics at P/N OHJs contribute to the recombination/dissociation of electron-hole pairs. Very often, the P-type materials donate electrons to the N-type materials, giving rise to charge-transfer complexes (CTCs) with a P(δ+) -N(δ-) configuration. A recently observed opposite charge-transfer direction in OHJs is also discussed (i.e., N-type material donates electrons to P-type material to form P(δ-) -N(δ+) ). Recent studies on the electronic structures of CTC-forming material pairs are also summarized. The formation of P(δ-) -N(δ+) -type CTCs and their correlations with exciplex emission are examined. Furthermore, the potential applications of CTCs in NIR photovoltaic devices are reviewed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Knowledge and ethical perception regarding organ donation among medical students

PubMed Central

2013-01-01

Background To determine the knowledge and ethical perception regarding organ donation amongst medical students in Karachi- Pakistan. Methods Data of this cross sectional study was collected by self administered questionnaire from MBBS students of Ziauddin University from 2010 to 2011. Sample size of 158 (83 First years and 75 Fourth years) were selected by convenient sampling and those students who were present and gave consent were included in the study. The data was analyzed by SPSS version 20. Results A total of 158 participants from Ziauddin Medical University filled out the questionnaire out of which 83(52.5%) were first years and 75(47.5%) were fourth year medical students. Mean age of sample was 20 ± 1.7. Majority of students were aware about organ donation with print and electronic media as the main source of information. 81.6% agreed that it was ethically correct to donate an organ. In the students’ opinion, most commonly donated organs and tissues were kidney, cornea, blood and platelet. Ideal candidates for donating organ were parents (81%). Regarding list of options for preference to receive an organ, most of the students agreed on young age group patients and persons with family. Willingness to donate was significantly associated with knowledge of allowance of organ donation in religion (P=0.000). Conclusion Both 1st year and 4th year students are aware of Organ Donation, but there is a significant lack of knowledge regarding the topic. PMID:24070261

Hyperpolarizable compounds and devices fabricated therefrom

DOEpatents

Therien, M.J.; DiMagno, S.G.

1998-07-21

Substituted compounds having relatively large molecular first order hyperpolarizabilities are provided, along with devices and materials containing them. In general, the compounds bear electron-donating and electron-withdrawing chemical substituents on a polyheterocyclic core. 13 figs.

Equatorial coordination of uranyl: Correlating ligand charge donation with the O yl-U-O yl asymmetric stretch frequency

DOE PAGES

Gibson, John K.; de Jong, Wibe A.; van Stipdonk, Michael J.; ...

2017-10-14

In uranyl coordination complexes, UO 2(L) n 2+, uranium in the formally dipositive [O=U=O] 2+ moiety is coordinated by n neutral organic electron donor ligands, L. The extent of ligand electron donation, which results in partial reduction of uranyl and weakening of the U=O bonds, is revealed by the magnitude of the red-shift of the uranyl asymmetric stretch frequency, ν 3 . This phenomenon appears in gas-phase complexes in which uranyl is coordinated by electron donor ligands: the ν 3 red-shift increases as the number of ligands and their proton affinity (PA) increases. Because PA is a measure of themore » enthalpy change associated with a proton-ligand interaction, which is much stronger and of a different nature than metal ion-ligand bonding, it is not necessarily expected that ligand PAs should reliably predict uranyl-ligand bonding and the resulting ν 3 red-shift. In this study, ν 3 was measured for uranyl coordinated by ligands with a relatively broad range of PAs, revealing a surprisingly good correlation between PA and ν 3 frequency. From computed ν 3 frequencies for bare UO 2 cations and neutrals, it is inferred that the effective charge of uranyl in UO 2(L) n 2+ complexes can be reduced to near zero upon ligation by sufficiently strong charge-donor ligands. The basis for the correlation between ν 3 and ligand PAs, as well as limitations and deviations from it, are considered. It is demonstrated that the correlation evidently extends to a ligand that exhibits polydentate metal ion coordination.« less

Photophysical properties and computational investigation on substituent effects on the structural and electronic properties of 3,6-di(thiophene-2-yl)-carbazole-based derivatives

NASA Astrophysics Data System (ADS)

Sriyab, Suwannee; Gleeson, Matthew Paul; Hannongbua, Supa; Suramitr, Songwut

2016-12-01

A series of 3,6-carbazole-based derivatives, 3,6-CzTh-(1), 3,6-CzTh-(2), 3,6-CzTh-(3) and 3,6-CzTh-(4), were synthesized to investigate the influence of structural distortion on intramolecular charge transfer (ICT) complexation between the conjugation components and carbazole core unit of the 3,6-carbazole-based derivatives. The 3,6-carbazole-based derivatives were synthesized and analysed using UV-Visible, photoluminescence spectroscopy and DFT calculations. The electron-donating substituents on the carbazole core unit, which was linked by formyl and acetyl at the 3,6-positions of the carbazole core so as to directly involve the electron-donating edge substituents in backbone, exhibited conjugation breaks in the middle of the carbazole core units. The break lead to a planar structure with an extraordinary ability to stabilize on the excited state resulting in a strong fluorescence quantum yield (Фfluo ≈ 0.6-0.7). The results of the Time-dependent density functional theory (TD-DFT) calculations were in agreement with the experimental results, and indicated that the low fluorescence of 3,6-CzTh-(1) and 3,6-CzTh-(2) is derived not only from intersystem crossing but also from internal conversion due to the proximity effect; this inference was also supported by the measurements of the photoluminescence spectra at low temperatures. In addition, factors leading efficiently to non-radiative processes were shown to be absent in 3,6-CzTh-(3) and 3,6-CzTh-(4). This work deepens our understanding of 3,6-di(thiophen-2-yl)-carbazole-based derivatives and provides insight into the future design of novel materials for improved fluorescence efficiencies and optoelectronic devices.

Umbilical cord blood: a guide for primary care physicians.

PubMed

Martin, Paul L; Kurtzberg, Joanne; Hesse, Brett

2011-09-15

Umbilical cord blood stem cell transplants are used to treat a variety of oncologic, genetic, hematologic, and immunodeficiency disorders. Physicians have an important role in educating, counseling, and offering umbilical cord blood donation and storage options to patients. Parents may donate their infant's cord blood to a public bank, pay to store it in a private bank, or have it discarded. The federal government and many state governments have passed laws and issued regulations regarding umbilical cord blood, and some states require physicians to discuss cord blood options with pregnant women. Five prominent medical organizations have published recommendations about cord blood donation and storage. Current guidelines recommend donation of umbilical cord blood to public banks when possible, or storage through the Related Donor Cord Blood Program when a sibling has a disease that may require a stem cell transplant. Experts do not currently recommend private banking for unidentified possible future use. Step-by-step guidance and electronic resources are available to physicians whose patients are considering saving or donating their infant's umbilical cord blood.

Measuring Critical Care Providers' Attitudes About Controlled Donation After Circulatory Death.

PubMed

Rodrigue, James R; Luskin, Richard; Nelson, Helen; Glazier, Alexandra; Henderson, Galen V; Delmonico, Francis L

2018-06-01

Unfavorable attitudes and insufficient knowledge about donation after cardiac death among critical care providers can have important consequences for the appropriate identification of potential donors, consistent implementation of donation after cardiac death policies, and relative strength of support for this type of donation. The lack of reliable and valid assessment measures has hampered research to capture providers' attitudes. Design and Research Aims: Using stakeholder engagement and an iterative process, we developed a questionnaire to measure attitudes of donation after cardiac death in critical care providers (n = 112) and examined its psychometric properties. Exploratory factor analysis, internal consistency, and validity analyses were conducted to examine the measure. A 34-item questionnaire consisting of 4 factors (Personal Comfort, Process Satisfaction, Family Comfort, and System Trust) provided the most parsimonious fit. Internal consistency was acceptable for each of the subscales and the total questionnaire (Cronbach α > .70). A strong association between more favorable attitudes overall and knowledge ( r = .43, P < .001) provides evidence of convergent validity. Multivariable regression analyses showed that white race ( P = .002) and more experience with donation after cardiac death ( P < .001) were significant predictors of more favorable attitudes. Study findings support the utility, reliability, and validity of a questionnaire for measuring attitudes in critical care providers and for isolating targets for additional education on donation after cardiac death.

Doped Graphene for DNA Analysis: the Electrochemical Signal is Strongly Influenced by the Kind of Dopant and the Nucleobase Structure

PubMed Central

Tian, Huidi; Wang, Lu; Sofer, Zdenek; Pumera, Martin; Bonanni, Alessandra

2016-01-01

Doping graphene with heteroatoms can alter the electronic and electrochemical properties of the starting material. Contrasting properties should be expected when the doping is carried out with electron donating species (n-type dopants) or with electron withdrawing species (p-type dopants). This in turn can have a profound influence on the electroanalytical performance of the doped material being used for the detection of specific probes. Here we investigate the electrochemical oxidation of DNA bases adenine, guanine, thymine and cytosine on two heteroatom-doped graphene platforms namely boron-doped graphene (p-type dopant) and nitrogen-doped graphene (n-type dopant). We found that overall, boron–doped graphene provided the best response in terms of electrochemical signal sensitivity for all bases. This is due to the electron deficiency of boron-doped graphene, which can promote the oxidation of DNA bases, as opposed to nitrogen-doped graphene which possesses an excess of electrons. Moreover, also the structure of the nucleobase was found to have significant influence on the obtained signal. Our study may open new frontiers in the electrochemical detection of DNA bases which is the first step for label-free DNA analysis. PMID:27623951

Standardized deceased donor kidney donation rates in the UK reveal marked regional variation and highlight the potential for increasing kidney donation: a prospective cohort study†

PubMed Central

Summers, D. M.; Johnson, R. J.; Hudson, A. J.; Collett, D.; Murphy, P.; Watson, C. J. E.; Neuberger, J. M.; Bradley, J. A.

2014-01-01

Background The UK has implemented a national strategy for organ donation that includes a centrally coordinated network of specialist nurses in organ donation embedded in all intensive care units and a national organ retrieval service for deceased organ donors. We aimed to determine whether despite the national approach to donation there is significant regional variation in deceased donor kidney donation rates. Methods The UK prospective audit of deaths in critical care was analysed for a cohort of patients who died in critical care between April 2010 and December 2011. Multivariate logistic regression was used to identify the factors associated with kidney donation. The logistic regression model was then used to produce risk-adjusted funnel plots describing the regional variation in donation rates. Results Of the 27 482 patients who died in a critical care setting, 1528 (5.5%) became kidney donors. Factors found to influence donation rates significantly were: type of critical care [e.g. neurointensive vs general intensive care: OR 1.53, 95% confidence interval (CI) 1.34–1.75, P<0.0001], patient ethnicity (e.g. ‘Asian’ vs ‘white’: OR 0.17, 95% CI 0.11–0.26, P<0.0001), age (e.g. age >69 vs age 18–39 yr: OR 0.2, 0.15–0.25, P<0.0001), and cause of death [e.g. ‘other’ (excluding ‘stroke’ and ‘trauma’) vs ‘trauma’: OR 0.04, 95% CI 0.03–0.05, P<0.0001]. Despite correction for these variables, kidney donation rates for the 20 UK kidney donor regions showed marked variation. The overall standardized donation rate ranged from 3.2 to 7.5%. Four regions had donation rates of >2 standard deviations (sd) from the mean (two below and two above). Regional variation was most marked for donation after circulatory death (DCD) kidney donors with 9 of the 20 regions demonstrating donation rates of >2 sd from the mean (5 below and 4 above). Conclusions The marked regional variation in kidney donation rates observed in this cohort after adjustment for factors strongly associated with donation rates suggests that there is considerable scope for further increasing kidney donation rates in the UK, particularly DCD. PMID:24335581

Bar code-based pre-transfusion check in pre-operative autologous blood donation.

PubMed

Ohsaka, Akimichi; Furuta, Yoshiaki; Ohsawa, Toshiya; Kobayashi, Mitsue; Abe, Katsumi; Inada, Eiichi

2010-10-01

The objective of this study was to demonstrate the feasibility of a bar code-based identification system for the pre-transfusion check at the bedside in the setting of pre-operative autologous blood donation (PABD). Between July 2003 and December 2008 we determined the compliance rate and causes of failure of electronic bedside checking for PABD transfusion. A total of 5627 (9% of all transfusions) PABD units were administered without a single mistransfusion. The overall rate of compliance with electronic checking was 99%. The bar code-based identification system was applicable to the pre-transfusion check for PABD transfusion. Copyright © 2010 Elsevier Ltd. All rights reserved.

Impact of a biospecimen collection seminar on willingness to donate biospecimens among Chinese Americans: results from a randomized, controlled community-based trial.

PubMed

Tong, Elisa K; Fung, Lei-Chun; Stewart, Susan L; Paterniti, Debora A; Dang, Julie H T; Chen, Moon S

2014-03-01

Biospecimen collection from diverse populations can advance cancer disparities research, but is currently underrepresented. We partnered with a community-based clinic serving Cantonese-speaking Chinese Americans to develop and revise an educational seminar on biospecimen collection. Through a randomized controlled trial (n = 395), the intervention seminar was compared with a control seminar (cancer prevention) on change in willingness to donate biospecimens. At baseline, many were willing to donate a biospecimen (saliva, urine, hair, toenails, blood, unused cancerous tissue) whether healthy or hypothetically had cancer. Also, many would donate because future generations would benefit, and few had concerns about donation. In logistic regression analyses, there was an intervention effect for willingness to donate: urine if had cancer [OR, 2.2; 95% confidence interval (CI), 1.3-3.7], toenails if healthy (OR, 2.1; 95% CI, 1.4-3.2) or had cancer (OR, 2.3; 95% CI, 2.0-2.7), hair if healthy (OR, 1.8; 95% CI, 1.3-2.5) or had cancer (OR, 2.8; 95% CI, 1.9-4.0), and unused cancerous tissue (OR, 1.8; 95% CI, 1.2-2.9). There was also an intervention effect for donating because future generations would benefit (OR, 2.0; 95% CI, 1.4-3.0), and this attitude was a strong independent predictor for willingness to donate all biospecimens, whether healthy or had cancer (OR, 2.9-4.2). Cantonese-speaking Chinese American participants of an educational seminar on biospecimen collection showed greater increases in willingness to donate biospecimens and donating for the benefit of future generations, than participants who attended a control seminar. Donating for the benefit of future generations is a theme that should be incorporated in messages that encourage biospecimen donation for Chinese Americans. ©2014 AACR.

Impact of a Biospecimen Collection Seminar on Willingness to Donate Biospecimens among Chinese Americans: Results from a Randomized, Controlled Community-Based Trial

PubMed Central

Tong, Elisa K.; Fung, Lei-Chun; Stewart, Susan L.; Paterniti, Debora A.; Dang, Julie H.T.; Chen, Moon S.

2014-01-01

Background Biospecimen collection from diverse populations can advance cancer disparities research, but is currently underrepresented. Methods We partnered with a community-based clinic serving Cantonese-speaking Chinese Americans to develop and revise an educational seminar on biospecimen collection. Through a randomized controlled trial (n = 395), the intervention seminar was compared with a control seminar (cancer prevention) on change in willingness to donate biospecimens. Results At baseline, many were willing to donate a biospecimen (saliva, urine, hair, toenails, blood, unused cancerous tissue) whether healthy or hypothetically had cancer. Also, many would donate because future generations would benefit, and few had concerns about donation. In logistic regression analyses, there was an intervention effect for willingness to donate: urine if had cancer [OR, 2.2; 95% confidence interval (CI), 1.3–3.7], toenails if healthy (OR, 2.1; 95% CI, 1.4–3.2) or had cancer (OR, 2.3; 95% CI, 2.0–2.7), hair if healthy (OR, 1.8; 95% CI, 1.3–2.5) or had cancer (OR, 2.8; 95% CI, 1.9–4.0), and unused cancerous tissue (OR, 1.8; 95% CI, 1.2–2.9). There was also an intervention effect for donating because future generations would benefit (OR, 2.0; 95% CI, 1.4–3.0), and this attitude was a strong independent predictor for willingness to donate all biospecimens, whether healthy or had cancer (OR, 2.9–4.2). Conclusion Cantonese-speaking Chinese American participants of an educational seminar on biospecimen collection showed greater increases in willingness to donate biospecimens and donating for the benefit of future generations, than participants who attended a control seminar. Impact Donating for the benefit of future generations is a theme that should be incorporated in messages that encourage biospecimen donation for Chinese Americans. PMID:24609848

Development of common metrics for donation attitude, subjective norm, perceived behavioral control, and intention for the blood donation context.

PubMed

France, Janis L; Kowalsky, Jennifer M; France, Christopher R; McGlone, Sarah T; Himawan, Lina K; Kessler, Debra A; Shaz, Beth H

2014-03-01

The Theory of Planned Behavior has been widely used in blood donation research, but the lack of uniform, psychometrically sound measures makes it difficult to draw firm conclusions or compare results across studies. Accordingly, the goal of this study was to develop such measures of donation attitude, subjective norm, perceived behavioral control, and intention. Exploratory and confirmatory factor analyses (CFAs) were conducted on survey responses collected from college students (n = 1080). The resulting scales were then administered to an independent sample of experienced donors (n = 433) for additional CFAs and to test whether the Theory of Planned Behavior model provided a good fit to the data. CFAs conducted on both samples support the use of six-item scales, with two factors each, to measure donation attitude, subjective norm, and perceived behavioral control and a single-factor three-item scale to measure donation intention. Further, structural equation modeling of these measures revealed that the Theory of Planned Behavior provided a strong fit to the data (comparative fit index, 0.976; root mean square error of approximation, 0.041; standardized root mean square residual, 0.055) and accounted for 73.7% of the variance in donation intention. The present findings confirm the applicability of the Theory of Planned Behavior to the blood donation context and more importantly provide psychometric support for the future use of four brief measures of donation attitude, subjective norm, perceived behavioral control, and intention. © 2013 American Association of Blood Banks.

Recruitment and retention of blood donors in four Canadian cities: an analysis of the role of community and social networks.

PubMed

Smith, André; Matthews, Ralph; Fiddler, Jay

2013-12-01

This study approaches the decision to donate blood as a dynamic process involving interplay between blood donors' personal motives, donors' social contexts, and the donor recruitment and retention activities of blood collection agencies. Data were gathered from four blood donation clinics using in-depth interviews with Canadian Blood Services employees, donors, and nondonors in 25 organizations participating in Life Link, a donor recruitment program that supports organizations to educate employees about the benefits of blood donation. Further data were obtained from ethnographic observations of blood collection and donor recruitment activities. Thematic analysis resulted in three umbrella themes: leveraging social networks, embedding the clinic in the community, and donating blood and social reciprocity. Donor recruitment activities at all four clinics enhanced awareness of blood donation in the workplace by using experienced donors to motivate their coworkers in making a first-time donation. Clinic employees reported varying success in improving awareness of blood donation in the broader community, in part because of varying employee engagement in community-wide activities and celebrations. Altruistic motives were mentioned by experienced donors, who also identified a desire to reciprocate to their community as another strong motive. This study contextualizes donor recruitment and retention as involving activities that tie blood donation to meaningful aspects of donors' social networks and community. The findings point to the need for further analyses of the institutional dimensions of blood donation to develop effective strategies beyond appeals to altruism. © 2013 American Association of Blood Banks.

F4TCNQ on Cu, Ag, and Au as prototypical example for a strong organic acceptor on coinage metals

NASA Astrophysics Data System (ADS)

Rangger, Gerold M.; Hofmann, Oliver T.; Romaner, Lorenz; Heimel, Georg; Bröker, Benjamin; Blum, Ralf-Peter; Johnson, Robert L.; Koch, Norbert; Zojer, Egbert

2009-04-01

Metal work-function modification with the help of organic acceptors is an efficient tool to significantly enhance the performance of modern state-of-the-art organic molecular electronic devices. Here, the prototypical organic acceptor 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, F4TCNQ, is characterized on Ag(111), Au(111), and Cu(111) metal surfaces by means of density-functional theory calculations. Particular attention is paid to charge-transfer processes at the metal-organic interface; a subtle balance between charge forward and backward donations in combination with a strong adsorption-induced geometry change are found to be responsible for the observed increase in the system work function. A larger effect is obtained for the metals with larger initial work function. Interestingly, this results in similar charge-injection barriers from the substrate metal into an organic semiconductor deposited on top of the F4TCNQ layer. The impact of the F4TCNQ packing density of the electronic properties of the interface is also addressed. Comparing the calculated energy-level alignments and work-function modifications to experimental data from ultraviolet photoelectron spectroscopy yields good agreement between experiments and simulations.

A theoretical study for electronic and transport properties of covalent functionalized MoS2 monolayer

NASA Astrophysics Data System (ADS)

Gao, Lijuan; Yang, Zhao-Di; Zhang, Guiling

2017-06-01

The geometries, electronic and electron transport properties of a series of functionalized MoS2 monolayers were investigated using density-functional theory (DFT) and the non-equilibrium Green's function (NEGF) methods. n-Propyl, n-trisilicyl, phenyl, p-nitrophenyl and p-methoxyphenyl are chosen as electron-donating groups. The results show covalent functionalization with electron-donating groups could make a transformation from typical semiconducting to metallic properties for appearance of midgap level across the Fermi level (Ef). The calculations of transport properties for two-probe devices indicate that conductivities of functionalized systems are obviously enhanced relative to pristine MoS2 monolayer. Grafted groups contribute to the major transport path and play an important role in enhancing conductivity. The NDR effect is found. The influence of grafted density is also studied. Larger grafted density leads to wider bandwidth of midgap level, larger current response of I-V curves and larger current difference between peak and valley.

Final Report Systems Level Analysis of the Function and Adaptive Responses of Methanogenic Consortia

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

Lovley, Derek R.

The purpose of this research was to determine whether the syntrophic microbial associations that are central to the functioning of methane-producing terrestrial wetlands can be predictively modeled with coupled multi-species genome-scale metabolic models. Such models are important because methane is an important greenhouse gas and there is a need to predictively model how the methane-producing microbial communities will respond to environmental perturbations, such as global climate change. The research discovered that the most prodigious methane-producing microorganisms on earth participate in a previously unrecognized form of energy exchange. The methane-producers Methanosaeta and Methanosarcina forge biological electrical connections with other microbes inmore » order to obtain electrons to reduce carbon dioxide to methane. This direct interspecies electron transfer (DIET) was demonstrated in complex microbial communities as well as in defined co-cultures. For example, metatranscriptomic analysis of gene expression in both natural communities and defined co-cultures demonstrated that Methanosaeta species highly expressed genes for the enzymes for the reduction of carbon dioxide to methane. Furthermore, Methanosaeta’s electron-donating partners highly expressed genes for the biological electrical connections known as microbial nanowires. A series of studies involving transcriptomics, genome resequencing, and analysis of the metabolism of a series of strains with targeted gene deletions, further elucidated the mechanisms and energetics of DIET in methane-producing co-cultures, as well as in a co-culture of Geobacter metallireducens and Geobacter sulfurreducens, which provided a system for studying DIET with two genetically tractable partners. Genome-scale modeling of DIET in the G. metallireducens/G. sulfurreducens co-culture suggested that DIET provides more energy to the electron-donating partner that electron exchange via interspecies hydrogen transfer, but that the performance of DIET may be strongly influenced by environmental factors. These studies have significantly modified conceptual models for carbon and electron flow in methane-producing environments and have developed a computational framework for predictive modeling the influence of environmental perturbations on methane-producing microbial communities. The results have important implications for modeling the response of methane-producing microbial communities to climate change as well as for the bioenergy strategy of converting wastes and biomass to methane.« less

A reward prediction error for charitable donations reveals outcome orientation of donators

PubMed Central

Kuss, Katarina; Falk, Armin; Trautner, Peter; Elger, Christian E.; Weber, Bernd

2013-01-01

The motives underlying prosocial behavior, like charitable donations, can be related either to actions or to outcomes. To address the neural basis of outcome orientation in charitable giving, we asked 33 subjects to make choices affecting their own payoffs and payoffs to a charity organization, while being scanned by functional magnetic resonance imaging (fMRI). We experimentally induced a reward prediction error (RPE) by subsequently discarding some of the chosen outcomes. Co-localized to a nucleus accumbens BOLD signal corresponding to the RPE for the subject's own payoff, we observed an equivalent RPE signal for the charity's payoff in those subjects who were willing to donate. This unique demonstration of a neuronal RPE signal for outcomes exclusively affecting unrelated others indicates common brain processes during outcome evaluation for selfish, individual and nonselfish, social rewards and strongly suggests the effectiveness of outcome-oriented motives in charitable giving. PMID:22198972

Opto-electronic conversion logic behaviour through dynamic modulation of electron/energy transfer states at the TiO2-carbon quantum dot interface.

PubMed

Wang, Fang; Zhang, Yonglai; Liu, Yang; Wang, Xuefeng; Shen, Mingrong; Lee, Shuit-Tong; Kang, Zhenhui

2013-03-07

Here we show a bias-mediated electron/energy transfer process at the CQDs-TiO(2) interface for the dynamic modulation of opto-electronic properties. Different energy and electron transfer states have been observed in the CQDs-TNTs system due to the up-conversion photoluminescence and the electron donation/acceptance properties of the CQDs decorated on TNTs.

Dynamic d-symmetry Bose condensate of a planar-large-bipolaron liquid in cuprate superconductors

NASA Astrophysics Data System (ADS)

Emin, David

2017-11-01

Planar-large-bipolarons can form if the ratio of the surrounding mediums' static to high-frequency dielectric constants is especially large, ε0/ε∞ >> 2. A large-bipolaron in p-doped La2CuO4 is modelled as two electrons being removed from the out-of-plane orbitals of four oxygen ions circumscribed by four copper ions of a CuO2 layer. These oxygen dianions relax inwardly as they donate electrons to the surrounding outwardly relaxing copper cations. This charge transfer generates the strong in-plane electron-lattice interaction needed to stabilise a large-bipolaron with respect to decomposing into polarons. The lowest-energy radial in-plane optic vibration of a large-bipolaron's four core oxygen ions with their associated electronic charges has d-symmetry. Electronic relaxation in response to multiple large-bipolarons' atomic vibrations lowers their frequencies to generate a phonon-mediated attraction among them which fosters their condensation into a liquid. This liquid features distinctive transport and optical properties. A large-bipolaron liquid's superconductivity can result when it undergoes a Bose condensation yielding macroscopic occupation of its ground state. The synchronised vibrations of large-bipolarons' core-oxygen ions with their electronic charges generate this Bose condensate's dynamic global d-symmetry.

Attitudes toward death criteria and organ donation among healthcare personnel and the general public.

PubMed

DuBois, James M; Anderson, Emily E

2006-03-01

To examine attitudes toward death criteria and their relation to attitudes and behaviors regarding organ donation. This article reviews empirical studies on the attitudes of healthcare personnel and the general public regarding death criteria and organ donation. The review was restricted to studies that had as a primary focus attitudes toward 1 or more of the following 3 specific criteria for determining death: (1) brain death, the irreversible loss of all functions of the entire brain; (2) higher brain death, the loss of cerebral cortex function alone; and (3) the circulatory-respiratory criteria commonly used in donation after cardiac death. Studies consistently show that the general public and some medical personnel are inadequately familiar with the legal and medical status of brain death; attitudes toward the dead donor rule are strong predictors of willingness to donate organs using controversial criteria; concerns about donation after cardiac death surround the withdrawal of life support more than the actual death criteria used; and concerns about death criteria correlate with less favorable attitudes toward organ donation. Both general and ethical education may serve to guide policy and facilitate family member requests and informed consent dialogues. Furthermore, helping families to understand and accept not only medical and legal criteria for determining death, but also ethical criteria for withdrawing life support may help them be more comfortable with their decisions.

Unraveling the mechanism of molecular doping in organic semiconductors.

PubMed

Mityashin, Alexander; Olivier, Yoann; Van Regemorter, Tanguy; Rolin, Cedric; Verlaak, Stijn; Martinelli, Nicolas G; Beljonne, David; Cornil, Jérôme; Genoe, Jan; Heremans, Paul

2012-03-22

The mechanism by which molecular dopants donate free charge carriers to the host organic semiconductor is investigated and is found to be quite different from the one in inorganic semiconductors. In organics, a strong correlation between the doping concentration and its charge donation efficiency is demonstrated. Moreover, there is a threshold doping level below which doping simply has no electrical effect. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Embryo donation and understanding of kinship: the impact of law and policy.

PubMed

Millbank, Jenni; Stuhmcke, Anita; Karpin, Isabel

2017-01-01

What is the impact of law and policy upon the experience of embryo donation for reproductive use? Access to, and experience of, embryo donation are influenced by a number of external factors including laws that impose embryo storage limits, those that frame counselling and approval requirements and allow for, or mandate, donor identity disclosure. To date only three qualitative studies in Australia and New Zealand have been completed on the experience of embryo donation for reproductive purposes, each with a small cohort of interviewees and divergent findings. Embryo donors, recipients, and would-be donors were interviewed between July 2010 and July 2012, with three additional interviews between September 2015 and September 2016, on their experiences of embryo donation. The sampling protocol had the advantage of addressing donation practices across multiple clinical sites under distinct legal frameworks. Participants were recruited from five Australian jurisdictions and across 11 clinical sites. Twenty-six participants were interviewed, comprising: 11 people who had donated embryos for the reproductive use of others (nine individuals and one couple), six recipients of donated embryos (four individuals and one couple) and nine individuals who had attempted to donate, or had a strong desire to donate, but had been prevented from doing so. In total, participants reported on 15 completed donation experiences; of which nine had resulted in offspring to the knowledge of the donor. Donors positively desired donation and did not find the decision difficult. Neither donors nor recipients saw the donation process as akin to adoption . The process and practice of donation varied considerably across different jurisdictions and clinical sites. Because the pool of donors and recipients is small, caution must be exercised over drawing general conclusions. Saturation was not reached on themes of counselling models and future contact. The differences between our findings and those of a previous study are attributable to varied legal and counselling regimes. Therefore, law and policy governing embryo storage limits, counselling protocols and identity disclosure shape the donation experience and how it is described. This research was supported by Discovery Project Grants DP 0986213 and 15010157 from the Australian Research Council and additional funding from UTS: Law. There are no conflicts of interest to declare. Not applicable. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology.

Unprecedented chemiluminescence behaviour during peroxyoxalate chemiluminescence of oxalates with fluorescent or electron-donating aryloxy groups.

PubMed

Koike, Ryu; Kato, Yuji; Motoyoshiya, Jiro; Nishii, Yoshinori; Aoyama, Hiromu

2006-01-01

A series of diaryl and bis(4-styrylphenyl) oxalates with electron-donating substituents or fluorescent moieties were subjected to the peroxyoxalate chemiluminescence (PO-CL) reaction, some of which were found to behave in a unprecedented manner. The reaction of bis(p-methyoxyphenyl) oxalate, as a representative example, emits light due not only to the emission from the externally added excited fluorophore, but also from the presumable excimer of p-methoxyphenol. Also, during the reaction of the bis(4-styrylphenyl) oxalates, the emission based on the fluorescence as well as the excimer of the eliminating group were observed. These experimental results suggest that such emitting species would be formed by an intra- and intermolecular electronic interaction with a high-energy intermediate, such as a dioxetanone. Copyright (c) 2006 John Wiley & Sons, Ltd.

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

Miller, Daniel P.; Tymińska, Nina; Zurek, Eva, E-mail: ezurek@buffalo.edu

Dispersion corrected Density Functional Theory calculations were employed to study the adsorption of benzenes derivatized with functional groups encompassing a large region of the activated/deactivated spectrum to the Ag(111) surface. Benzenes substituted with weak activating or deactivating groups, such as methyl and fluoro, do not have a strong preference for adsorbing to a particular site on the substrate, with the corrugations in the potential energy surface being similar to those of benzene. Strong activating (N(CH{sub 3}){sub 2}) and deactivating (NO{sub 2}) groups, on the other hand, possess a distinct site preference. The nitrogen in the former prefers to lie abovemore » a silver atom (top site), but in the latter a hollow hexagonal-closed-packed (H{sub hcp}) site of the Ag(111) surface is favored instead. Benzenes derivatized with classic activating groups donate electron density from their highest occupied molecular orbital to the surface, and those functionalized with deactivating groups withdraw electron density from the surface into orbitals that are unoccupied in the gas phase. For benzenes functionalized with two substituents, the groups that are strongly activating or deactivating control the site preference and the other groups assume sites that are, to a large degree, dictated by their positions on the benzene ring. The relative stabilities of the ortho, meta, and para positional isomers of disubstituted benzenes can, in some cases, be modified by adsorption to the surface.« less

The nature of the metal-CO interaction and bonding

NASA Technical Reports Server (NTRS)

Bagus, P. S.; Nelin, C. J.; Bauschlicher, C. W., Jr.

1984-01-01

The adsorption of CO on metal surfaces is represented by molecular orbital cluster models of CO at an on top site and adsorbed normal to the surface carbon end down. Ab initio SCF and MCSCF calculations are performed for several clusters. The new constrained space orbital variation CSOV approach is used to analyze the bonding and to compare CO adsorption on Al, representative of sp metals, with that on Cu, representative of transition metals. There is a large repulsion between the superposed free CO and metal charge distributions which is considerably smaller for Cu than for Al because there are fewer valence sigma electrons for Cu than for Al. The CSOV analysis shows that the metal to CO pi donation is much more important than the CO to metal sigma donation. It is also shown that for Cu, the d pi contribution to the metal pi donation is larger than the valence 4p pi contribution. The d pi donation is compared between Fe, Ni, and Cu and this donation and the metal-CO interaction are found to be different in the order Fe greater than Ni greater than Cu.

Ancillary hospital personnel faced with organ donation and transplantation.

PubMed

Ríos, A; Conesa, C; Ramírez, P; Galindo, P J; Martínez, L; Fernández, O M; Montoya, M J; Rodríguez, M M; Lucas, D; Parrilla, P

2006-04-01

To reduce the number of family organ donation refusals, it is necessary not only to act on the general public but also on the health care system. In this respect, there are data suggesting that the percentage of hospital personnel against donation is high, especially among ancillary personnel. The objective herein was to analyze the attitudes of ancillary hospital professionals toward donation of their own organs and determine factors that conditioned such attitudes. A random sample in a third-level hospital with a solid organ transplant program was stratified by ancillary services: administrative, porters, maintenance, cleaning, and cooking. Attitudes toward donation of one's own organs after death were evaluated using a questionnaire on psychosocial aspects validated in our area. It included various psychosocial variables that could affect such attitudes. The Student t test and chi-square test were used to evaluate the data. We analyzed 277 respondents of mean age 43 +/- 8 years and 96% women. The level of acceptance of organ donation was 64% (n = 178), whereas 46% were either against or undecided (n = 98). The variables which determined the attitudes were understanding of brain death (P = .004); attitude toward cadaveric manipulation, especially toward autopsy (P = .013) and cremation (P = .004); concern about mutilation after donation (P = .014); religion (P = .032); partner's attitude toward donation (P < .0001); and possibility of needing an organ in the future (P = .031). Ancillary hospital personnel had similar attitudes toward donation as those of the general public as observed in other studies. The attitudes were determined by many psychosocial factors. A campaign to raise awareness among professionals has become a priority, given that working in a hospital, their unfavorable attitude could have a strong negative impact on the general public.

Novel High Efficient Organic Photovoltaic Materials

NASA Technical Reports Server (NTRS)

Sun, Sam; Haliburton, James; Wang, Yi-Qing; Fan, Zhen; Taft, Charles; Maaref, Shahin; Bailey, Sheila (Technical Monitor)

2003-01-01

Solar energy is a renewable, nonpolluting, and most abundant energy source for human exploration of a remote site or outer space. In order to generate appreciable electrical power in space or on the earth, it is necessary to collect sunlight from large areas and with high efficiency due to the low density of sunlight. Future organic or polymer (plastic) solar cells appear very attractive due to their unique features such as light weight, flexible shape, tunability of energy band-gaps via versatile molecular or supramolecular design, synthesis, processing and device fabrication schemes, and much lower cost on large scale industrial production. It has been predicted that supramolecular and nano-phase separated block copolymer systems containing electron rich donor blocks and electron deficient acceptor blocks may facilitate the charge carrier separation and migration due to improved electronic ultrastructure and morphology in comparison to polymer composite system. This presentation will describe our recent progress in the design, synthesis and characterization of a novel block copolymer system containing donor and acceptor blocks covalently attached. Specifically, the donor block contains an electron donating alkyloxy derivatized polyphenylenevinylene (RO-PPV), the acceptor block contains an electron withdrawing alkyl-sulfone derivatized polyphenylenevinylene (SF-PPV). The key synthetic strategy includes the synthesis of each individual block first, then couple the blocks together. While the donor block has a strong PL emission at around 560 nm, and acceptor block has a strong PL emission at around 520 nm, the PL emissions of final block copolymers are severely quenched. This verifies the expected electron transfer and charge separation due to interfaces of donor and acceptor nano phase separated blocks. The system therefore has potential for variety light harvesting applications, including high efficient photovoltaic applications.

Acceptability and feasibility of a culturally tailored Internet-delivered intervention to promote blood donation in Blacks.

PubMed

Robbins, Mark L; Paiva, Andrea L; Amoyal, Nicole R; Brick, Leslie; Kessler, Debra A; Burditt, Caitlin; Caltabiano, Melinda; Shaz, Beth H

2015-03-01

A pilot test of a computer-tailored intervention designed to promote blood donation among Blacks was conducted. Intervention content, based on the transtheoretical model, offered participants individually and culturally tailored information on blood donation with emphasis on need specific to race (e.g., sickle-cell disease). Black adults (N = 150) with a diversity of blood donation experience were recruited from a blood center and a survey recruitment website. Posttest assessment included a 14-item evaluation and transtheoretical model questions. Participants rated the program positively (81.3% to 98.7% of participants agreeing or strongly agreeing with evaluation items). For example, 98.7% of respondents reported that the program gave sound advice and that personal feedback was easily understood, and 87.3% felt the program was designed for people like themselves. Ninety-five percent of participants reported that they would recommend the program to others. There were no significant differences in ratings based on demographics. Qualitative responses support program acceptability. Furthermore, pre- and postprogram assessments indicated an increase in intention to donate, t(149) = 3.56, p = .001, d = .29. With acceptability and feasibility confirmed, the next steps are to test efficacy and cost-effectiveness for use to increase blood donation, particularly in priority populations. © 2014 Society for Public Health Education.

Incentives for Blood Donation: A Discrete Choice Experiment to Analyze Extrinsic Motivation.

PubMed

Sadler, Andrew; Shi, Ling; Bethge, Susanne; Mühlbacher, Axel

2018-04-01

Background: Demographic trends affect size and age structure of populations. One of the consequences will be an increasing need for blood products to treat age-related diseases. Donation services rely on voluntariness and charitable motivation. It might be questioned whether there will be sufficient blood supply with voluntary donation. The present study focused on elicitation of preferences for incentives and aimed to contribute to the discussion on how to increase donation rates. Methods: A self-administered discrete choice experiment (DCE) was applied. Respondents were repeatedly asked to choose between hypothetical blood donation centers. In case of reluctance to receiving incentives a none-option was included. Random parameter logit (RPL) and latent class models (LCM) were used for analysis. Results: The study sample included 416 college students from the US and Germany. Choice decisions were significantly influenced by the characteristics of the donation center in the DCE. Incentives most preferred were monetary compensation, paid leave, and blood screening test. LCM identified subgroups with preference heterogeneity. Small subgroups indicated moderate to strong aversion to incentives. Conclusion: The majority of the sample positively responded to incentives and indicated a willingness to accept incentives. In face of future challenges, the judicious use and appropriate utilization of incentives might be an option to motivate potential donors and should be open to discussion.

Breakdown in the organ donation process and its effect on organ availability.

PubMed

Razdan, Manik; Degenholtz, Howard B; Kahn, Jeremy M; Driessen, Julia

2015-01-01

Background. This study examines the effect of breakdown in the organ donation process on the availability of transplantable organs. A process breakdown is defined as a deviation from the organ donation protocol that may jeopardize organ recovery. Methods. A retrospective analysis of donation-eligible decedents was conducted using data from an independent organ procurement organization. Adjusted effect of process breakdown on organs transplanted from an eligible decedent was examined using multivariable zero-inflated Poisson regression. Results. An eligible decedent is four times more likely to become an organ donor when there is no process breakdown (adjusted OR: 4.01; 95% CI: 1.6838, 9.6414; P < 0.01) even after controlling for the decedent's age, gender, race, and whether or not a decedent had joined the state donor registry. However once the eligible decedent becomes a donor, whether or not there was a process breakdown does not affect the number of transplantable organs yielded. Overall, for every process breakdown occurring in the care of an eligible decedent, one less organ is available for transplant. Decedent's age is a strong predictor of likelihood of donation and the number of organs transplanted from a donor. Conclusion. Eliminating breakdowns in the donation process can potentially increase the number of organs available for transplant but some organs will still be lost.

Organ Donation Campaigns: Perspective of Dialysis Patient's Family Members.

PubMed

Tumin, Makmor; Raja Ariffin, Raja Noriza; Mohd Satar, NurulHuda; Ng, Kok-Peng; Lim, Soo-Kun; Chong, Chin-Sieng

2014-07-01

Solving the dilemma of the organ shortage in Malaysia requires educating Malaysians about organ donation and transplantation. This paper aims at exploring the average Malaysian households ' preferred channels of campaigns and the preferred campaigners in a family setting, targeting at the dialysis family members. We analyzed the responses of 350 respondents regarding organ donation campaigns. The respondents are 2 family members of 175 dialysis patients from 3 different institutions. The information on respondents' willingness to donate and preferred method and channel of organ donation campaign were collected through questionnaire. Malaysian families have a good tendency to welcome campaigns in both the public and private (their homes) spheres. We also found that campaigns facilitated by the electronic media (Television and Radio) and executed by experienced doctors are expected to optimize the outcomes of organ donation, in general. Chi-square tests show that there are no significant differences in welcoming campaigns among ethnics. However, ethnics preferences over the campaign methods and campaigners are significantly different (P <0.05). Ethnic differences imply that necessary modifications on the campaign channels and campaigners should also be taken under consideration. By identifying the preferred channel and campaigners, this study hopes to shed some light on the ways to overcome the problem of organ shortage in Malaysia.

Organ Donation Campaigns: Perspective of Dialysis Patient's Family Members

PubMed Central

TUMIN, Makmor; RAJA ARIFFIN, Raja Noriza; MOHD SATAR, NurulHuda; NG, Kok-Peng; LIM, Soo-Kun; CHONG, Chin-Sieng

2014-01-01

Abstract Background Solving the dilemma of the organ shortage in Malaysia requires educating Malaysians about organ donation and transplantation. This paper aims at exploring the average Malaysian households ’ preferred channels of campaigns and the preferred campaigners in a family setting, targeting at the dialysis family members. Methods We analyzed the responses of 350 respondents regarding organ donation campaigns. The respondents are 2 family members of 175 dialysis patients from 3 different institutions. The information on respondents’ willingness to donate and preferred method and channel of organ donation campaign were collected through questionnaire. Results Malaysian families have a good tendency to welcome campaigns in both the public and private (their homes) spheres. We also found that campaigns facilitated by the electronic media (Television and Radio) and executed by experienced doctors are expected to optimize the outcomes of organ donation, in general. Chi-square tests show that there are no significant differences in welcoming campaigns among ethnics. However, ethnics preferences over the campaign methods and campaigners are significantly different (P <0.05). Conclusion Ethnic differences imply that necessary modifications on the campaign channels and campaigners should also be taken under consideration. By identifying the preferred channel and campaigners, this study hopes to shed some light on the ways to overcome the problem of organ shortage in Malaysia. PMID:25909060

2016 America's Recycle Day

NASA Image and Video Library

2016-11-15

Members of the Sustainability team at NASA's Kennedy Space Center in Florida accept items donated by employees in conjunction with America Recycles Day. America Recycles Day is a nationally recognized initiative dedicated to promoting recycling in the United States. Kennedy partnered with several organizations in order to donate as many of the items as possible to those who could use them the most in the Space Coast community. Space center personnel brought in electronic waste, gently used household goods, clothing and more.

Substituent Effects in the Benzene Dimer are Due to Direct Interactions of the Substituents with the Unsubstituted Benzene

PubMed Central

Wheeler, Steven E.; Houk, K. N.

2009-01-01

The prevailing views of substituent effects in the sandwich configuration of the benzene dimer are flawed. For example, in the polar/π model of Cozzi and co-workers (J. Am. Chem. Soc. 1992, 114, 5729), electron-withdrawing substituents enhance binding in the benzene dimer by withdrawing electron density from the π-cloud of the substituted ring, reducing the repulsive electrostatic interaction with the non-substituted benzene. Conversely, electron-donating substituents donate excess electrons into the π-system and diminish the π-stacking interaction. We present computed interaction energies for the sandwich configuration of the benzene dimer and 24 substituted dimers, as well as sandwich complexes of substituted benzenes with perfluorobenzene. While the computed interaction energies correlate well with σm values for the substituents, interaction energies for related model systems demonstrate that this trend is independent of the substituted ring. Instead, the observed trends are consistent with direct electrostatic and dispersive interactions of the substituents with the unsubstituted ring. PMID:18652453

Electronic Interplay between TTF and Extended-TCNQ Electrophores along a Ruthenium Bis(acetylide) Linker.

PubMed

Vacher, Antoine; Auffray, Morgan; Barrière, Frédéric; Roisnel, Thierry; Lorcy, Dominique

2017-11-17

A bis(TTF-butadiynyl) ruthenium D-D'-D complex, with intramolecular electronic interplay between the three electron-donating electrophores, was easily converted through a cycloaddition-retroelectrocyclization with TCNQ into a D-A-D'-A-D pentad complex, which exhibits an intense intramolecular charge transfer together with an electronic interplay between the two acceptors along the conjugated organometallic bridge.

Interfacial charge separation and photovoltaic efficiency in Fe(ii)-carbene sensitized solar cells.

PubMed

Pastore, Mariachiara; Duchanois, Thibaut; Liu, Li; Monari, Antonio; Assfeld, Xavier; Haacke, Stefan; Gros, Philippe C

2016-10-12

The first combined theoretical and photovoltaic characterization of both homoleptic and heteroleptic Fe(ii)-carbene sensitized photoanodes in working dye sensitized solar cells (DSSCs) has been performed. Three new heteroleptic Fe(ii)-NHC dye sensitizers have been synthesized, characterized and tested. Despite an improved interfacial charge separation in comparison to the homoleptic compounds, the heteroleptic complexes did not show boosted photovoltaic performances. The ab initio quantitative analysis of the interfacial electron and hole transfers and the measured photovoltaic data clearly evidenced fast recombination reactions for heteroleptics, even associated with un unfavorable directional electron flow, and hence slower injection rates, in the case of homoleptics. Notably, quantum mechanics calculations revealed that deprotonation of the not anchored carboxylic function in the homoleptic complex can effectively accelerate the electron injection rate and completely suppress the electron recombination to the oxidized dye. This result suggests that introduction of strong electron-donating substituents on the not-anchored carbene ligand in heteroleptic complexes, in such a way of mimicking the electronic effects of the carboxylate functionality, should yield markedly improved interfacial charge generation properties. The present results, providing for the first time a detailed understanding of the interfacial electron transfers and photovoltaic characterization in Fe(ii)-carbene sensitized solar cells, open the way to a rational molecular engineering of efficient iron-based dyes for photoelectrochemical applications.

Effects of financial incentives on the intention to consent to organ donation: a questionnaire survey.

PubMed

Mayrhofer-Reinhartshuber, D; Fitzgerald, A; Benetka, G; Fitzgerald, R

2006-11-01

Shortage of donor organs is a serious problem for transplantation medicine. One controversial suggestion to increase the number of organ donors is financial incentives for consent. The aim of this study was to test whether different forms and amounts of financial incentives were apt to increase the consent to organ donation. Data were collected via questionnaires in urban and rural regions of Austria and randomly assigned to settings with three different amounts of financial incentives. The questionnaire was designed by using the theory of planned behaviour of Ajzen. Parents 69 mothers and 35 fathers; ages 25 to 65 years were evaluated for intention to consent to organ donation, perceived social norm, and positive/ negative aspects of organ donation without and with various financial incentives. The intention to consent to organ donation dropped highly significantly (Z = -7.556 P = .000) from the basic condition (M = 1.13; confidence interval [CIs] 0.78 to 1.51) to the condition with financial incentives (M = -1.58; CI, 1.96 to -1.15). No influence of the amount of financial incentive was observed. Highly significant differences were measured between both conditions for the social norm (Z = -5.638; P < .000) and the attitude toward organ donation (Z = -1.962; P < .05; Z = -2.104; P < .035). Financial incentives led to decreased consents and elicited strong rejections and negative reactions of the participants. Taking money for consent to organ donation seems to be a strict taboo for most people in Austrian society.

Two-photon or higher-order absorbing optical materials and methods of use

NASA Technical Reports Server (NTRS)

Marder, Seth (Inventor); Perry, Joseph (Inventor)

2012-01-01

Compositions capable of simultaneous two-photon absorption and higher order absorptivities are provided. Compounds having a donor-pi-donor or acceptor-pi-acceptor structure are of particular interest, where the donor is an electron donating group, acceptor is an electron accepting group, and pi is a pi bridge linking the donor and/or acceptor groups. The pi bridge may additionally be substituted with electron donating or withdrawing groups to alter the absorptive wavelength of the structure. Also disclosed are methods of generating an excited state of such compounds through optical stimulation with light using simultaneous absorption of photons of energies individually insufficient to achieve an excited state of the compound, but capable of doing so upon simultaneous absorption of two or more such photons. Applications employing such methods are also provided, including controlled polymerization achieved through focusing of the light source(s) used.

Aryl sulfonate based anticancer alkylating agents.

PubMed

Sheikh, Hamdullah Khadim; Arshad, Tanzila; Kanwal, Ghazala

2018-05-01

This research work revolves around synthesis of antineoplastic alkylating sulfonate esters with dual alkylating sites for crosslinking of the DNA strands. These molecules were evaluated as potential antineoplastic cross linking alkylating agents by reaction with the nucleoside of Guanine DNA nucleobase at both ends of the synthesized molecule. Synthesis of the alkylating molecules and the crosslinking with the guanosine nucleoside was monitored by MALDITOF mass spectroscopy. The synthesized molecule's crosslinking or adduct forming rate with the nucleoside was compared with that of 1,4 butane disulfonate (busulfan), in form of time taken for the appearance of [M+H] + . It was found that aryl sulfonate leaving group was causing higher rate of nucleophilic attack by the Lewis basic site of the nucleobase. Furthermore, the rate was also found to be a function of electron withdrawing or donating nature of the substituent on the aryl ring. Compound with strong electron withdrawing substituent on the para position of the ring reacted fastest. Hence, new alkylating agents were synthesized with optimized or desired reactivity.

Embryo donation and understanding of kinship: the impact of law and policy

PubMed Central

Millbank, Jenni; Stuhmcke, Anita; Karpin, Isabel

2017-01-01

STUDY QUESTION What is the impact of law and policy upon the experience of embryo donation for reproductive use? SUMMARY ANSWER Access to, and experience of, embryo donation are influenced by a number of external factors including laws that impose embryo storage limits, those that frame counselling and approval requirements and allow for, or mandate, donor identity disclosure. WHAT IS KNOWN ALREADY To date only three qualitative studies in Australia and New Zealand have been completed on the experience of embryo donation for reproductive purposes, each with a small cohort of interviewees and divergent findings. STUDY DESIGN, SIZE, DURATION Embryo donors, recipients, and would-be donors were interviewed between July 2010 and July 2012, with three additional interviews between September 2015 and September 2016, on their experiences of embryo donation. The sampling protocol had the advantage of addressing donation practices across multiple clinical sites under distinct legal frameworks. PARTICIPANTS/MATERIALS, SETTINGS, METHODS Participants were recruited from five Australian jurisdictions and across 11 clinical sites. Twenty-six participants were interviewed, comprising: 11 people who had donated embryos for the reproductive use of others (nine individuals and one couple), six recipients of donated embryos (four individuals and one couple) and nine individuals who had attempted to donate, or had a strong desire to donate, but had been prevented from doing so. In total, participants reported on 15 completed donation experiences; of which nine had resulted in offspring to the knowledge of the donor. MAIN RESULTS AND THE ROLE OF CHANCE Donors positively desired donation and did not find the decision difficult. Neither donors nor recipients saw the donation process as akin to adoption . The process and practice of donation varied considerably across different jurisdictions and clinical sites. LIMITATIONS, REASONS FOR CAUTION Because the pool of donors and recipients is small, caution must be exercised over drawing general conclusions. Saturation was not reached on themes of counselling models and future contact. WIDER IMPLICATIONS OF THE FINDINGS The differences between our findings and those of a previous study are attributable to varied legal and counselling regimes. Therefore, law and policy governing embryo storage limits, counselling protocols and identity disclosure shape the donation experience and how it is described. STUDY FUNDING/COMPETING INTEREST(S) This research was supported by Discovery Project Grants DP 0986213 and 15010157 from the Australian Research Council and additional funding from UTS: Law. There are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER Not applicable. PMID:27927845

Renal cortical volume: High correlation with pre- and post-operative renal function in living kidney donors.

PubMed

Gardan, Edouard; Jacquemont, Lola; Perret, Christophe; Heudes, Pierre-Marie; Gourraud, Pierre-Antoine; Hourmant, Maryvonne; Frampas, Eric; Limou, Sophie

2018-02-01

CT volumetry has previously been proposed as an alternative to scintigraphy for the evaluation of pre-donation split renal function and the prediction of post-donation renal function in living kidney donors. The aim of our study was to retrospectively assess the relevance of three CT volumetry techniques for estimating pre-donation kidney function and predicting the risk for chronic kidney disease (CKD) at 1-year post-nephrectomy in a French cohort of living donors using isotopic measures of kidney function. Kidney volume was quantified pre-donation for 105 donors using three methods total parenchymal three-dimensional renal volume (3DRV), total parenchymal renal volume contouring (RVCt), and renal cortical volume (RCoV). Subjects also had a 51Cr-EDTA scintigraphy to measure glomerular filtration rate (mGFR) pre-donation and 1-year after donation. For each volume, we tested for association with mGFR using univariate regression models, and computed receiver operating characteristics analyses to assess their predictive potential of post-donation CKD. Our population was composed of healthy subjects, who were predominantly female (69%) with a median age at donation of 51yo. Median mGFR was 102 mL/min/1.73 m 2 at pre-donation and 66 mL/min/1.73 m 2 1-year after nephrectomy. The pre-donation median volume of the preserved kidney was 156 cm 3 , 163 cm 3 and 99 cm 3 for the 3DRV, RVCt and RCoV methods respectively, with a high correlation observed between each technique (R > 0.84). For all methods, total kidney volume was significantly associated with pre-donation mGFR (P < 0.001). Preserved kidney volume was also strongly correlated with post-donation mGFR (P < 0.0001), with the strongest correlation observed for RCoV (R = 0.60 vs. R = 0.39 and R = 0.51 for 3DRV and RVCt, respectively). Finally, the RCoV method yielded the best predictive value of 1-year post-donation CKD (AUC = 0.80 vs. AUC = 0.76 and 0.70 for RVCt and 3DRV, respectively). In our cohort of healthy donors with measured kidney function, cortical volumetry (RCoV) appears as the best volumetric technique to use as a surrogate to scintigraphy for estimating pre-donation split renal function and predicting post-donation renal outcomes. Copyright © 2017 Elsevier B.V. All rights reserved.

A-π-D-π-A Electron-Donating Small Molecules for Solution-Processed Organic Solar Cells: A Review.

PubMed

Wang, Zhen; Zhu, Lingyun; Shuai, Zhigang; Wei, Zhixiang

2017-11-01

Organic solar cells based on semiconducting polymers and small molecules have attracted considerable attention in the last two decades. Moreover, the power conversion efficiencies for solution-processed solar cells containing A-π-D-π-A-type small molecules and fullerenes have reached 11%. However, the method for designing high-performance, photovoltaic small molecules still remains unclear. In this review, recent studies on A-π-D-π-A electron-donating small molecules for organic solar cells are introduced. Moreover, the relationships between molecular properties and device performances are summarized, from which inspiration for the future design of high performance organic solar cells may be obtained. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Models of Charity Donations and Project Funding in Social Networks

NASA Astrophysics Data System (ADS)

Wojciechowski, Adam

One of the key fundaments of building a society is common interest or shared aims of the group members. This research work is a try to analyze web-based services oriented towards money collection for various social and charity projects. The phenomenon of social founding is worth a closer look at because its success strongly depends on the ability to build an ad-hoc or persistent groups of people sharing their believes and willing to support external institutions or individuals. The paper presents a review of money collection sites, various models of donation and money collection process as well as ways how the projects' results are reported to their founders. There is also a proposal of money collection service, where donators are not charged until total declared help overheads required resources to complete the project. The risk of missing real donations for declared payments, after the collection is closed, can be assessed and minimized by building a social network.

2016 America's Recycle Day

NASA Image and Video Library

2016-11-15

Members of the Sustainability team at NASA's Kennedy Space Center in Florida look over appliances donated for reuse or recycling in conjunction with America Recycles Day. America Recycles Day is a nationally recognized initiative dedicated to promoting recycling in the United States. Kennedy partnered with several organizations in order to donate as many of the items as possible to those who could use them the most in the Space Coast community. Space center personnel brought in electronic waste, gently used household goods, clothing and more.

2016 America's Recycle Day

NASA Image and Video Library

2016-11-15

Members of the Sustainability team at NASA's Kennedy Space Center in Florida sort through items donated for reuse or recycling in conjunction with America Recycles Day. America Recycles Day is a nationally recognized initiative dedicated to promoting recycling in the United States. Kennedy partnered with several organizations in order to donate as many of the items as possible to those who could use them the most in the Space Coast community. Space center personnel brought in electronic waste, gently used household goods, clothing and more.

Assessment of blood donation intention among medical students in Pakistan--An application of theory of planned behavior.

PubMed

Faqah, Anadil; Moiz, Bushra; Shahid, Fatima; Ibrahim, Mariam; Raheem, Ahmed

2015-12-01

Theory of Planned Behavior proposes a model which can measure how human actions are guided. It has been successfully utilized in the context of blood donation. We employed a decision-making framework to determine the intention of blood donation among medical students who have never donated blood before the study. Survey responses were collected from 391 medical students from four various universities on a defined questionnaire. The tool composed of 20 questions that were formulated to explain donation intention based on theory of planned behavior. The construct included questions related to attitude, subjective norm and perceived behavior control, descriptive norm, moral norm, anticipated regret, donation anxiety and religious norm. Pearson's correlational relationships were measured between independent and dependent variables of intention to donate blood. ANOVA was applied to observe the model fit; a value of 0.000 was considered statistically significant. A multiple regression analysis was conducted to explore the relative importance of the main independent variables in the prediction of intention. Multi-collinearity was also evaluated to determine that various independent variables determine the intention. The reliability of measures composed of two items was assessed using inter-item correlations. Three hundred and ninety-one medical students (M:F; 1:2.2) with mean age of 21.96 years ± 1.95 participated in this study. Mean item score was 3.8 ± 0.83. Multiple regression analysis suggested that perceived behavioral control, anticipated regret and attitude were the most influential factors in determining intention of blood donation. Donation anxiety was least correlated and in fact bore a negative correlation with intention. ANOVA computed an F value of 199.082 with a p-value of 0.000 indicating fitness of model. The value of R square and adjusted R square was 0.811 and 0.807 respectively indicating strong correlation between various independent and dependent variables. Medical students as novice blood donors showed a positive attitude toward blood donation. Theory of planned behavior can be successfully utilized in determining the antecedents toward blood donation behavior. Copyright © 2015 Elsevier Ltd. All rights reserved.

Attitude to blood donation in Saudi Arabia

PubMed Central

Abdel Gader, Abdel Galil M.; Osman, Abdel Moniem A.; Al Gahtani, Furgah H.; Farghali, Mohamed N.; Ramadan, Ali H.; Al-Momen, Abdel Kareem M.

2011-01-01

Background and Objectives: The blood donor system in the Kingdom of Saudi Arabia depends on a combination of voluntary and involuntary donors. The aim of this study is to explore the attitudes, beliefs and motivations of Saudis toward blood donation. Materials and Methods: The study was conducted at the Donor Centers at King Khalid University Hospital (KKUH) Blood Bank and King Saud University Students Health Center, Riyadh. A self-administered questionnaire was distributed to donors (n = 517) and nondonors (n = 316), between February and June 2008. All were males. Results: Ninety-nine percent of the respondents showed positive attitude toward blood donations and its importance for patients care, and object the importation of blood from abroad. Blood donors: Ninety-one percent agree that that blood donation is a religious obligation, 91% think no compensation should be given, 63% will accept a token gift, 34% do not object to donating six times/year and 67% did not mind coming themselves to the donor center to give blood. Nondonors: Forty-six percent were not asked to give blood and those who were asked mentioned fear (5%) and lack of time (16%) as their main deterrents. Reasons for rejection as donors include underweight and age (71%) and health reasons (19%). Seventy-five percent objected to money compensation but 69% will accept token gifts and 92% will donate if a relative/friend needs blood. Conclusion: These results reflect an encouraging strong positive attitude toward blood donation. Further future planning with emphasis on educational/publicity programs and careful organization of donor recruitment campaigns could see the dream of total voluntary nonremunerated blood donations should not take long to be true. PMID:21897588

Humin as an electron donor for enhancement of multiple microbial reduction reactions with different redox potentials in a consortium.

PubMed

Zhang, Dongdong; Zhang, Chunfang; Xiao, Zhixing; Suzuki, Daisuke; Katayama, Arata

2015-02-01

A solid-phase humin, acting as an electron donor, was able to enhance multiple reductive biotransformations, including dechlorination of pentachlorophenol (PCP), dissimilatory reduction of amorphous Fe (III) oxide (FeOOH), and reduction of nitrate, in a consortium. Humin that was chemically reduced by NaBH4 served as an electron donor for these microbial reducing reactions, with electron donating capacities of 0.013 mmol e(-)/g for PCP dechlorination, 0.15 mmol e(-)/g for iron reduction, and 0.30 mmol e(-)/g for nitrate reduction. Two pairs of oxidation and reduction peaks within the humin were detected by cyclic voltammetry analysis. 16S rRNA gene sequencing-based microbial community analysis of the consortium incubated with different terminal electron acceptors, suggested that Dehalobacter sp., Bacteroides sp., and Sulfurospirillum sp. were involved in the PCP dechlorination, dissimilatory iron reduction, and nitrate reduction, respectively. These findings suggested that humin functioned as a versatile redox mediator, donating electrons for multiple respiration reactions with different redox potentials. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Positional effects of hydroxy groups on catalytic activity of proton-responsive half-sandwich Cp*Iridium(III) complexes

DOE PAGES

Suna, Yuki; Fujita, Etsuko; Ertem, Mehmed Z.; ...

2014-11-12

Proton-responsive half-sandwich Cp*Ir(III) complexes possessing a bipyridine ligand with two hydroxy groups at the 3,3'-, 4,4'-, 5,5'- or 6,6'-positions (3DHBP, 4DHBP, 5DHBP, or 6DHBP) were systematically investigated. UV-vis titration data provided average pK a values of the hydroxy groups on the ligands. Both hydroxy groups were found to deprotonate in the pH 4.6–5.6 range for the 4–6DHBP complexes. One of the hydroxy groups of the 3DHBP complex exhibited the low pK a value of < 0.4 because the deprotonation is facilitated by the strong intramolecular hydrogen bond formed between the generated oxyanion and the remaining hydroxy group, which in turnmore » leads to an elevated pK a value of ~13.6 for the second deprotonation step. The crystal structures of the 4– and 6DHBP complexes obtained from basic aqueous solutions revealed their deprotonated forms. The intramolecular hydrogen bond in the 3DHBP complex was also observed in the crystal structures. The catalytic activities of these complexes in aqueous phase reactions, at appropriate pH, for hydrogenation of carbon dioxide (pH 8.5), dehydrogenation of formic acid (pH 1.8), transfer hydrogenation reactions using formic acid/formate as a hydrogen source (pH 7.2 and 2.6) were investigated to compare the positional effects of the hydroxy groups. The 4– and 6DHBP complexes exhibited remarkably enhanced catalytic activities under basic conditions because of the resonance effect of the strong electrondonating oxyanions, whereas the 5DHBP complex exhibited negligible activity despite the presence of electron-donating groups. The 3DHBP complex exhibited relatively high catalytic activity at low pH owing to the one strong electron-donating oxyanion group stabilized by the intramolecular hydrogen bond. DFT calculations were employed to study the mechanism of CO₂ hydrogenation by the 4DHBP and 6DHBP complexes, and comparison of the activation free energies of the H₂ heterolysis and CO₂ insertion steps indicated that H₂ heterolysis is the rate-determining step for both complexes. The presence of a pendent base in the 6DHBP complex was found to facilitate the rate-determining step, and renders 6DHBP a more effective catalyst for formate production.« less

Energetic and electronic computation of the two-hydrogen atom donation process in catecholic and non-catecholic anthocyanidins.

PubMed

Ali, Hussein M; Ali, Isra H

2018-03-15

Antioxidant activity of anthocyanidins is greatly affected by the 3-hydroxyl group and/or a catecholic moiety. The two-hydrogen atom donation process is frequently used to explain the high antioxidant activity of polyphenolic compounds leading to the formation of stable diketones e.g. 1,2-quinones. Thermodynamic parameters, HOMO and spin density were computed to identify the favoured path, either through the 3-hydroxyl group or through the catecholic moiety in a series of catecholic and non-catecholic 3-oxy- (and deoxy)-anthocyanidins. DFT calculations showed that the donation process in non-catecholic anthocyanidins depended on the substituents on ring B. Anthocyanidins with 3',5'-diOMe groups showed donation through 3,4'-OH or, otherwise, through 3,5-OH groups. Catecholic 3-oxyanthocyanidins, on the other hand, showed donation through the 3,4'-OH path rather than the catecholic path (4',3'-path). The 3,4'-path was favoured by the formation of planar 3-radicals in the first step and the stabilization of 4'-radicals in the second step by H-bonding with the 3'-OH group. Copyright © 2017 Elsevier Ltd. All rights reserved.

Human immunodeficiency virus prevalence, incidence, and residual transmission risk in first-time and repeat blood donations in Zimbabwe: implications on blood safety.

PubMed

Mapako, Tonderai; Mvere, David A; Chitiyo, McLeod E; Rusakaniko, Simbarashe; Postma, Maarten J; van Hulst, Marinus

2013-10-01

National Blood Service Zimbabwe human immunodeficiency virus (HIV) risk management strategy includes screening and discarding of first-time donations, which are collected in blood packs without an anticoagulant (dry pack). To evaluate the impact of discarding first-time donations on blood safety the HIV prevalence, incidence, and residual risk in first-time and repeat donations (wet packs) were compared. Donor data from 2002 to 2010 were retrieved from a centralized national electronic donor database and retrospectively analyzed. Chi-square test was used to compare HIV prevalence with relative risk (RR), and the RR point estimates and 95% confidence interval (CI) are reported. Trend analysis was done using Cochran-Armitage trend test. HIV residual risk estimates were determined using published residual risk estimation models. Over the 9 years the overall HIV prevalence estimates are 1.29% (n = 116,058) and 0.42% (n = 434,695) for first-time and repeat donations, respectively. The overall RR was 3.1 (95% CI, 2.9-3.3; p < 0.0001). The overall mean residual transmission risk of HIV window phase donations in first-time was 1:7384 (range, 1:11,308-1:5356) and in repeat donors it was 1:5496 (range, 1:9943-1:3347). The significantly high HIV prevalence estimates recorded in first-time over repeat donations is indicative of the effectiveness of the HIV risk management strategy. However, comparable residual transmission risk estimates in first-time and repeat donors point to the need to further review the risk management strategies. Given the potential wastage of valuable resources, future studies should focus on the cost-effectiveness and utility of screening and discarding first-time donations. © 2013 American Association of Blood Banks.

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

Mieno, H.; Kabe, R.; Allendorf, M. D.

Here, the first metal–organic framework exhibiting thermally activated delayed fluorescence (TADF) was developed. The zirconium-based framework (UiO-68-dpa) uses a newly designed linker composed of a terphenyl backbone, an electron-accepting carboxyl group, and an electron-donating diphenylamine and exhibits green TADF emission with a photoluminescence quantum yield of 30% and high thermal stability.

Expanding the Supply of Pasteurized Donor Milk: Understanding Why Peer-to-Peer Milk Sharers in the United States Do Not Donate to Milk Banks.

PubMed

Perrin, Maryanne Tigchelaar; Goodell, L Suzanne; Fogleman, April; Pettus, Hannah; Bodenheimer, Amanda L; Palmquist, Aunchalee E L

2016-05-01

Lactating women in the United States have several options for what they do with excess breast milk, including donating to milk banks that serve medically fragile infants, sharing directly with families seeking milk, and selling to individuals or for-profit entities. The World Health Organization and the US Surgeon General have issued calls to increase access to pasteurized donor milk for medically fragile infants. To explore how lactating women with a surplus of breast milk come to the decision to share their milk with a peer rather than donate to a milk bank. A qualitative design using a grounded theory approach was employed. Semistructured telephone interviews were conducted with 27 women who had shared milk with a peer but not with a milk bank. Five dominant themes were identified: a strong belief in the value of breast milk, unexpected versus planned donation, sources of information regarding milk exchange, concerns and knowledge gaps about milk banks, and helping and connecting. This research offers insights into potential strategies for promoting milk bank donation among peer-to-peer milk sharers, including developing donor education campaigns focused on knowledge gaps regarding milk banks and developing health care professional referral programs that can reduce barriers associated with the convenience of milk bank donation. © The Author(s) 2016.

Prospective audit to evaluate the potential of the coronial system to increase solid organ donation

PubMed Central

Twamley, Huw; Haigh, Andrew; Williment, Claire; Hudson, Cara; Whitney, Julie; Neuberger, James

2016-01-01

Objectives Anecdotal evidence suggests that organ donation from deceased donors referred to the Coroner/Procurator Fiscal (PF) could be increased if all followed best practice. The aim of this prospective audit was to establish how referrals affected organ donation and to develop evidence-based guidelines to ensure that organ donation can be facilitated safely without interfering in the Coroner/PF's investigative process. Design Prospective audit. Setting All acute National Health Service Hospitals in the UK where deceased organ donation was considered. Participants 1437 deceased patients who met the eligibility criteria for organ donation and were referred to Coroner/PF. Main outcome measures Number of cases where permission for transplantation was given, number of organs where permission was refused and number of organs which might have been transplanted if all had followed best practice. Results Full permission for organ retrieval was given in 87% cases and partial permission in 9%. However, if full permission had been given where no autopsy was performed or restrictions seemed unjustified, up to 77 organs (22 lungs, 22 kidneys, 9 pancreases, 9 livers, 8 hearts and 7 small bowels) could have been available for transplant. Conclusions Coroners/PFs and their officers show strong support for transplantation but improvement in practice could result in a small but significant increase in life-saving and life-enhancing transplants. PMID:27401356

Structure–function relationships in single molecule rectification by N-phenylbenzamide derivatives

DOE PAGES

Koenigsmann, Christopher; Ding, Wendu; Koepf, Matthieu; ...

2016-06-30

Here, we examine structure–function relationships in a series of N-phenylbenzamide (NPBA) derivatives by using computational modeling to identify molecular structures that exhibit both rectification and good conductance together with experimental studies of bias-dependent single molecule conductance and rectification behavior using the scanning tunneling microscopy break-junction technique. From a large number of computationally screened molecular diode structures, we have identified NPBA as a promising candidate, relative to the other structures that were screened. We demonstrate experimentally that conductance and rectification are both enhanced by functionalization of the NPBA 4-carboxamido-aniline moiety with electron donating methoxy groups, and are strongly correlated with themore » energy of the conducting frontier orbital relative to the Fermi level of the gold leads used in break-junction experiments.« less

Structure–function relationships in single molecule rectification by N-phenylbenzamide derivatives

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

Koenigsmann, Christopher; Ding, Wendu; Koepf, Matthieu

Here, we examine structure–function relationships in a series of N-phenylbenzamide (NPBA) derivatives by using computational modeling to identify molecular structures that exhibit both rectification and good conductance together with experimental studies of bias-dependent single molecule conductance and rectification behavior using the scanning tunneling microscopy break-junction technique. From a large number of computationally screened molecular diode structures, we have identified NPBA as a promising candidate, relative to the other structures that were screened. We demonstrate experimentally that conductance and rectification are both enhanced by functionalization of the NPBA 4-carboxamido-aniline moiety with electron donating methoxy groups, and are strongly correlated with themore » energy of the conducting frontier orbital relative to the Fermi level of the gold leads used in break-junction experiments.« less

Copolymer semiconductors comprising thiazolothiazole or benzobisthiazole, or benzobisoxazole electron acceptor subunits, and electron donor subunits, and their uses in transistors and solar cells

DOEpatents

Jenekhe, Samson A; Subramaniyan, Selvam; Ahmed, Eilaf; Xin, Hao; Kim, Felix Sunjoo

2014-10-28

The inventions disclosed, described, and/or claimed herein relate to copolymers comprising copolymers comprising electron accepting A subunits that comprise thiazolothiazole, benzobisthiazole, or benzobisoxazoles rings, and electron donating subunits that comprise certain heterocyclic groups. The copolymers are useful for manufacturing organic electronic devices, including transistors and solar cells. The invention also relates to certain synthetic precursors of the copolymers. Methods for making the copolymers and the derivative electronic devices are also described.

Quantitative studies on structure-DPPH• scavenging activity relationships of food phenolic acids.

PubMed

Jing, Pu; Zhao, Shu-Juan; Jian, Wen-Jie; Qian, Bing-Jun; Dong, Ying; Pang, Jie

2012-11-01

Phenolic acids are potent antioxidants, yet the quantitative structure-activity relationships of phenolic acids remain unclear. The purpose of this study was to establish 3D-QSAR models able to predict phenolic acids with high DPPH• scavenging activity and understand their structure-activity relationships. The model has been established by using a training set of compounds with cross-validated q2 = 0.638/0.855, non-cross-validated r2 = 0.984/0.986, standard error of estimate = 0.236/0.216, and F = 139.126/208.320 for the best CoMFA/CoMSIA models. The predictive ability of the models was validated with the correlation coefficient r2(pred) = 0.971/0.996 (>0.6) for each model. Additionally, the contour map results suggested that structural characteristics of phenolics acids favorable for the high DPPH• scavenging activity might include: (1) bulky and/or electron-donating substituent groups on the phenol ring; (2) electron-donating groups at the meta-position and/or hydrophobic groups at the meta-/ortho-position; (3) hydrogen-bond donor/electron-donating groups at the ortho-position. The results have been confirmed based on structural analyses of phenolic acids and their DPPH• scavenging data from eight recent publications. The findings may provide deeper insight into the antioxidant mechanisms and provide useful information for selecting phenolic acids for free radical scavenging properties.

The impact of multiple blood donations on the risk of cardiovascular diseases: Insight of lipid profile.

PubMed

Bani-Ahmad, M A; Khabour, O F; Gharibeh, M Y; Alshlool, K N

2017-11-01

The reduction in blood viscosity and iron store were proposed to be connected to the reduction in the risk of cardiovascular disease (CVD) among multiple blood donors. Herein, we evaluated the modulation of serum lipids levels in accordance with donation events. Furthermore, atherogenic impacts on the risk of CVD were investigated. A total of 100 voluntarily male donors were included in the study. Fifty donors were multiple time donors (MTD) and 50 were single time donors (STD). Levels of serum lipids were determined and atherogenic indices including TG/HDL and CHO/HDL ratios were calculated. QRISK2 parameters were determined to evaluate the 10-years risk of developing CVD. Among MTD, there were significantly higher serum levels of triglycerides (TG) and very low-density lipoproteins (VLDL) combined with significantly lower HDL level. These modulations were significantly correlated to the extent of donation. Both CHO/HDL and TG/HDL ratios were also significantly higher among MTD. However, only TG/HDL ratio was strongly correlated to the donation extent even when controlled for age, BMI and smoking status. Despite the significant difference in QRISK2 parameters between study groups, none of these parameters was correlated to the extent of donation when controlling for age, BMI and smoking status. We demonstrate that multiple blood donation is associated with an unfavorable modulation of serum levels of lipids that is influenced by donation extent. This modulation is not associated with an increased risk of CVD but may weakly contribute in a higher risk for coronary heart disease (CHD). Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Manufacture of silicon-based devices having disordered sulfur-doped surface layers

DOEpatents

Carey, III; Edward, James [Newton, MA; Mazur, Eric [Concord, MA

2008-04-08

The present invention provides methods of fabricating a radiation-absorbing semiconductor wafer by irradiating at least one surface location of a silicon substrate, e.g., an n-doped crystalline silicon, by a plurality of temporally short laser pulses, e.g., femtosecond pulses, while exposing that location to a substance, e.g., SF.sub.6, having an electron-donating constituent so as to generate a substantially disordered surface layer (i.e., a microstructured layer) that incorporates a concentration of that electron-donating constituent, e.g., sulfur. The substrate is also annealed at an elevated temperature and for a duration selected to enhance the charge carrier density in the surface layer. For example, the substrate can be annealed at a temperature in a range of about 700 K to about 900 K.

Assessment of knowledge about biobanking among healthcare students and their willingness to donate biospecimens.

PubMed

Merdad, Leena; Aldakhil, Lama; Gadi, Rawan; Assidi, Mourad; Saddick, Salina Y; Abuzenadah, Adel; Vaught, Jim; Buhmeida, Abdelbaset; Al-Qahtani, Mohammed H

2017-05-02

Biobanks and biospecimen collections are becoming a primary means of delivering personalized diagnostics and tailoring individualized therapeutics. This shift towards precision medicine (PM) requires interactions among a variety of stakeholders, including the public, patients, healthcare providers, government, and donors. Very few studies have investigated the role of healthcare students in biobanking and biospecimen donations. The main aims of this study were (1) to evaluate the knowledge of senior healthcare students about biobanks and (2) to assess the students' willingness to donate biospecimens and the factors influencing their attitudes. A cross-sectional study was conducted among senior healthcare students at King Abdulaziz University (KAU), Saudi Arabia. The data were obtained using a self-administered questionnaire in English. In addition to the respondents' biographical data section, the questionnaire assessed the respondents' general knowledge about biobanking, the factors influencing their willingness to donate biospecimens to biobanks and their general attitudes towards biomedical research. A total of 597 senior healthcare students were included in the study. The general knowledge score was 3.2 (±1.6) out of 7. Only approximately 44% and 27% of students were aware of the terms "Human Genome Project" (HGP) and "biobank," respectively. The majority of the students (89%) were willing to donate biospecimens to biobanks. Multiple factors were significantly associated with their willingness to donate, including their perceived general health (p < 0.001), past experience with both tissue testing (p < 0.04) and tissue donation (p < 0.001), biobanking knowledge score (p < 0.001) and biomedical research attitude score (p < 0.001). The main reasons for students' willingness to donate were advancement of medical research and societal benefits, whereas misuse of biospecimens and confidentiality breaches were the main reasons for a reluctance to donate. Despite their strong willingness to donate biospecimens, students exhibited a notable lack of knowledge about biobanking and the HGP. To expedite the transition towards PM, it is highly recommended to enhance healthcare curricula by including more educational and awareness programmes to familiarize students with OMICs technologies in addition to the scope of research and clinical applications.

41 CFR 101-42.1102-6 - Noncertified and certified electronic products.

Code of Federal Regulations, 2013 CFR

2013-07-01

... radiation test to determine the acceptability for use and/or modification to bring it into compliance with..., noncertified black and white television receivers, and noncertified microwave ovens. (2) Donation of electronic... it: (A) Is aware of the potential danger in using the product without a radiation test to determine...

[Living donors for kidney transplantation: ethical and legal challenges].

PubMed

Mamzer-Bruneel, Marie-France; Fournier, Catherine; Legendre, Christophe

2010-05-01

Living donor kidney transplantation has developed very heterogeneously worldwide despite excellent results and without taking into account the context of global organ shortage. Such a heterogeneity highlights persistent ethical issues, whereas organ trafficking is emerging as an organized transplant tourism reinforcing the need for strong national legal frameworks. Despite its powerful regulation system, which ensures standardization, transparency and accountability of support for donation, France remains reluctant to enlarge the circle of legal donors, whereas it would be the first step to give a greater role to living organ donation.

Water-Soluble Fe(II)−H2O Complex with a Weak O−H Bond Transfers a Hydrogen Atom via an Observable Monomeric Fe(III)−OH

PubMed Central

Brines, Lisa M.; Coggins, Michael K.; Poon, Penny Chaau Yan; Toledo, Santiago; Kaminsky, Werner; Kirk, Martin L.

2015-01-01

Understanding the metal ion properties that favor O−H bond formation versus cleavage should facilitate the development of catalysts tailored to promote a specific reaction, e.g., C−H activation or H2O oxidation. The first step in H2O oxidation involves the endothermic cleavage of a strong O−H bond (BDFE = 122.7 kcal/mol), promoted by binding the H2O to a metal ion, and by coupling electron transfer to proton transfer (PCET). This study focuses on details regarding how a metal ion’s electronic structure and ligand environment can tune the energetics of M(HO−H) bond cleavage. The synthesis and characterization of an Fe(II)−H2O complex, 1, that undergoes PCET in H2O to afford a rare example of a monomeric Fe(III)−OH, 7, is described. High-spin 7 is also reproducibly generated via the addition of H2O to {[FeIII(OMe2N4(tren))]2-(µ-O)}2+ (8). The O−H bond BDFE of Fe(II)−H2O (1) (68.6 kcal/mol) is calculated using linear fits to its Pourbaix diagram and shown to be 54.1 kcal/mol less than that of H2O and 10.9 kcal/mol less than that of [Fe(II)(H2O)6]2+. The O−H bond of 1 is noticeably weaker than the majority of reported Mn+(HxO−H) (M = Mn, Fe; n+ = 2+, 3+; x = 0, 1) complexes. Consistent with their relative BDFEs, Fe(II)−H2O (1) is found to donate a H atom to TEMPO•, whereas the majority of previously reported Mn+−O(H) complexes, including [MnIII(SMe2N4(tren))(OH)]+ (2), have been shown to abstract H atoms from TEMPOH. Factors responsible for the weaker O−H bond of 1, such as differences in the electron-donating properties of the ligand, metal ion Lewis acidity, and electronic structure, are discussed. PMID:25611075

2016 America's Recycle Day

NASA Image and Video Library

2016-11-15

A sign tells NASA Kennedy Space Center employees they have come to the right place to donate items for reuse or recycling in conjunction with America Recycles Day. America Recycles Day is a nationally recognized initiative dedicated to promoting recycling in the United States. Kennedy partnered with several organizations in order to donate as many of the items as possible to those who could use them the most in the Space Coast community. Space center personnel brought in electronic waste, gently used household goods, clothing and more. The two-day event was sponsored by Kennedy's Sustainability team.

2016 America's Recycle Day

NASA Image and Video Library

2016-11-15

Members of the Sustainability team at NASA's Kennedy Space Center in Florida set up giveaway items and sort through donations for reuse or recycling in conjunction with America Recycles Day. America Recycles Day is a nationally recognized initiative dedicated to promoting recycling in the United States. Kennedy partnered with several organizations in order to donate as many of the items as possible to those who could use them the most in the Space Coast community. Space center personnel brought in electronic waste, gently used household goods, clothing and more. The two-day event was sponsored by Kennedy's Sustainability team.

Bicarbonate stimulates the electron donation from Mn²⁺ to P₆₈₀⁺ in isolated D1/D2/cytochrome b559 complex.

PubMed

Zharmukhamedov, S K; Allakhverdiev, S I; Smolova, T N; Klimov, V V

2013-12-05

Influence of bicarbonate on the efficiency of the electron donation from Mn(2+) to P₆₈₀(+) in isolated D1/D2/cytochrome b559 complex was investigated. All the experiments were carried out in a medium depleted of HCO₃(-)/CO₂. Kinetics of photoinduced absorbance changes (ΔA) at different wavelengths and decrease of chlorophyll fluorescence yield (-ΔF) related to photoaccumulation of reduced pheophytin, the intermediary electron acceptor of photosystem II (PSII), in the presence of Mn(2+) under anaerobic conditions were measured. Addition of bicarbonate (1 mM) increased the amplitude of these ΔA and -ΔF at least by a factor of 3. Measurements of the photoinduced ΔA, related to photooxidation of the primary electron donor of PSII, chlorophyll P₆₈₀, were done in the presence of silicomolybdate as electron acceptor. These results show that the addition of 0.05 mM Mn(2+) alone or jointly with 1 mM bicarbonate induces a 20% and 70%-decrease of the magnitude of the ΔA at 680 nm. The effect of Mn(2+) (in the presence and absence of bicarbonate) was completely eliminated by the addition of 12 mM EDTA. All these bicarbonate effects were not observed if MgCl₂ or formate were used instead of MnCl₂ and bicarbonate, respectively. In the absence of Mn(2+), bicarbonate induced none of the mentioned above effects (increase of photoaccumulation of reduced pheophytin and decrease of photooxidation of P680). The presented data suggest that bicarbonate stimulates the electron donation from Mn(2+) to D1/D2/cyt b559 reaction center evidently due to formation of easily oxidizable Mn-bicarbonate complexes. Copyright © 2013 Elsevier B.V. All rights reserved.

The short circuit current improvement in P3HT:PCBM based polymer solar cell by introducing PSBTBT as additional electron donor.

PubMed

Sun, Lu; Shen, Liang; Mengd, Fanxu; Xu, Peng; Guo, Wenbin; Ruan, Shengping

2014-05-01

Here we demonstrate the influence of electron-donating polymer addition on the performance of poly(3-hexylthiophene) (P3HT):1 -(3-methoxycarbonyl)-propyl-1-phenyl-(6,6) C61 (PCBM) solar cells. Poly[(4,42-bis(2-ethylhexyl) dithieno [3,2-b:22,32-d] silole)-2,6-diylalt-(2,1,3-benzothiadiazole)-4,7-diyl] (PSBTBT) was chosen as the electron-donating polymer to improve the short circuit current (J(sc)) due to its distinct absorption in the near-IR range and similar HOMO level with that of P3HT. In the study, we found that J(sc) was improved for ternary blend (P3HT:PSBTBT:PCBM) solar cells. The dependence of device performance was investigated. J(sc) got decreased with increasing the ratio of PSBTBT. Result showed that J(sc) of ternary blend solar cells was improved greatly after thermal annealing at 150 degrees C, close to that of the binary blend (PSBTBT:PCBM) solar cells.

Prospective audit to evaluate the potential of the coronial system to increase solid organ donation.

PubMed

Twamley, Huw; Haigh, Andrew; Williment, Claire; Hudson, Cara; Whitney, Julie; Neuberger, James

2016-07-08

Anecdotal evidence suggests that organ donation from deceased donors referred to the Coroner/Procurator Fiscal (PF) could be increased if all followed best practice. The aim of this prospective audit was to establish how referrals affected organ donation and to develop evidence-based guidelines to ensure that organ donation can be facilitated safely without interfering in the Coroner/PF's investigative process. Prospective audit. All acute National Health Service Hospitals in the UK where deceased organ donation was considered. 1437 deceased patients who met the eligibility criteria for organ donation and were referred to Coroner/PF. Number of cases where permission for transplantation was given, number of organs where permission was refused and number of organs which might have been transplanted if all had followed best practice. Full permission for organ retrieval was given in 87% cases and partial permission in 9%. However, if full permission had been given where no autopsy was performed or restrictions seemed unjustified, up to 77 organs (22 lungs, 22 kidneys, 9 pancreases, 9 livers, 8 hearts and 7 small bowels) could have been available for transplant. Coroners/PFs and their officers show strong support for transplantation but improvement in practice could result in a small but significant increase in life-saving and life-enhancing transplants. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Carbon black as an alternative cathode material for electrical energy recovery and transfer in a microbial battery.

PubMed

Zhang, Xueqin; Guo, Kun; Shen, Dongsheng; Feng, Huajun; Wang, Meizhen; Zhou, Yuyang; Jia, Yufeng; Liang, Yuxiang; Zhou, Mengjiao

2017-08-01

Rather than the conventional concept of viewing conductive carbon black (CB) to be chemically inert in microbial electrochemical cells (MECs), here we confirmed the redox activity of CB for its feasibility as an electron sink in the microbial battery (MB). Acting as the cathode of a MB, the solid-state CB electrode showed the highest electron capacity equivalent of 18.58 ± 0.46 C/g for the unsintered one and the lowest capacity of 2.29 ± 0.48 C/g for the one sintered under 100% N 2 atmosphere. The capacity vibrations of CBs were strongly in coincidence with the abundances of C=O moiety caused by different pretreatments and it implied one plausible mechanism based on CB's surface functionality for its electron capturing. Once subjected to electron saturation, CB could be completely regenerated by different strategies in terms of electrochemical discharging or donating electrons to biologically-catalyzed nitrate reduction. Surface characterization also revealed that CB's regeneration fully depended on the reversible shift of C=O moiety, further confirming the functionality-based mechanism for CB's feasibility as the role of MB's cathode. Moreover, resilience tests demonstrated that CB cathode was robust for the multi-cycles charging-discharging operations. These results imply that CB is a promising alternative material for the solid-state cathode in MBs.

Attitude towards organ donation in German medical students.

PubMed

Terbonssen, Tobias; Settmacher, Utz; Wurst, Christine; Dirsch, Olaf; Dahmen, Uta

2016-12-01

It is well known that personal decision making in respect to organ donation is highly dependent on the balance of knowledge, trust, and fear. We wanted to explore the attitude of German medical students towards organ donation and investigate the relationship between knowledge, trust, and fear in this special subgroup. We conducted an online survey utilizing (1) the snowball effect of using Facebook groups and advertisement as well as (2) mailing lists of medical faculties in Germany for distribution. We surveyed 1370 medical students. 75.8 % (N = 988) of the participants stated to carry an organ donor card and allowed their organs to be donated. 1.8 % (N = 23) refused donation. 22.5 % (N = 293) did not carry an organ donor card. Analysis of the "decided" versus the "undecided" group revealed substantial differences regarding transplantation knowledge (mean knowledge score of 4.23 vs. 3.81; P < 0.001), trust in (mean trust score 4.11 vs. 3.39; P < 0.001), and fear of (mean fear score 1.63 vs. 2.22; P < 0.001) organ donation. 45.9 % of the undecided group (N = 134) opted for accessing additional information material. After reading the info material, 22.7 % (N = 29) stated their willingness to sign a donor card, whereas 76.6 % (N = 98) still could not reach a decision. The willingness to potentially act as organ donor was related to the pre-existent knowledge, trust, and fear. Access to information material did promote the decision towards organ donation in a group of previously undecided medical students. This advocates initiating information campaigns even in population groups with strong medical background.

Pathological characteristics of liver allografts from donation after brain death followed by cardiac death in pigs.

PubMed

Ye, Hui; Wang, Dong-Ping; Zhang, Chuan-Zhao; Zhang, Long-Juan; Wang, Hao-Chen; Li, Zhuo-Hui; Chen, Zhen; Zhang, Tao; Cai, Chang-Jie; Ju, Wei-Qiang; Ma, Yi; Guo, Zhi-Yong; He, Xiao-Shun

2014-10-01

Donation after brain death followed by circulatory death (DBCD) is a unique practice in China. The aim of this study was to define the pathologic characteristics of DBCD liver allografts in a porcine model. Fifteen male pigs (25-30 kg) were allocated randomly into donation after brain death (DBD), donation after circulatory death (DCD) and DBCD groups. Brain death was induced by augmenting intracranial pressure. Circulatory death was induced by withdrawal of life support in DBCD group and by venous injection of 40 mL 10% potassium chloride in DCD group. The donor livers were perfused in situ and kept in cold storage for 4 h. Liver tissue and common bile duct samples were collected for hematoxylin and eosin staining, TUNEL testing and electron microscopic examination. Spot necrosis was found in hepatic parenchyma of DBD and DBCD groups, while a large area of necrosis was shown in DCD group. The apoptosis rate of hepatocytes in DBD [(0.56±0.30)%] and DBCD [(0.50 ± 0.11)%] groups was much lower than that in DCD group [(3.78±0.33)%] (P<0.05). And there was no significant difference between DBD group and DBCD group (P>0.05)). The structures of bile duct were intact in both DBD and DBCD groups, while the biliary epithelium was totally damaged in DCD group. Under electron microscope, the DBD hepatocytes were characterized by intact cell membrane, well-organized endoplasmic reticulum, mild mitochondria edema and abundant glycogens. Broken cell membrane, mild inflammatory cell infiltration and sinusoidal epithelium edema, as well as reduced glycogen volume, were found in the DBCD hepatocytes. The DCD hepatocytes had more profound cell organelle injury and much less glycogen storage. In conclusion, the preservation injury of DBCD liver allografts is much less severe than that of un-controlled DCD, but more severe than that of DBD liver allografts under electron microscope, which might reflect post-transplant liver function to some extent.

Health content analysis of organ donation and transplantation news on Turkish television channels and in Turkish print media.

PubMed

Colak, M Yavuz; Hekimoglu, D; Ersoy, K; Sozen, F; Haberal, M

2010-01-01

The media affects individuals' behaviors, especially by means of news and advertisements. In this study, we evaluated health content of organ donation and transplantation news in the printed media and on television programs for a 1-year period in Turkey. We examined 2449 news items in 230 newspapers and magazines; 1179 news programs on 45 television channels, all concerning organ donation and transplantation. The news obtained from the Media Pursuit Center were transferred to an electronic file to evaluate the format and content of the news. Nine variables were examined about the scope and the formal characteristics of the news: the publication name, its type, the province, the date, the headline, the title length, the presence of a photograph, or its kind, the news size, and the page number. In the content analysis of the news, we also examined 9 variables: the topic, the message of the headline, the property of the words in the title, the identification of photographs in the news, the age, gender of actors in the news, as well as donor or recipient. In a summary, print media and television channels, failed to show sufficient information about organ donation and transplantation. The percentage of news about organ donation and transplantation was small and mostly negative items in the media. On television channels, sufficient place was not given to organ donation and transplantation. The news in printed media and on television channels was not about motivated or altruistic behavior. The pattern of organ donation and transplantation news is important in terms of perception and comment by the public. Furthermore it directly affects the perception of the news by the reader.

Vasculitis Foundation

MedlinePlus

... investigators, care providers, and health systems to develop research methods to electronically collect health records and patient-reported ... more » View All News Connect with us on social media! Join VF Donate Next Page » Next Page » ...

The Contrasting Alkylations of 4-(Dimethylaminomethyl)pyridine and 4-(Dimethylamino)pyridine: An Organic Chemistry Experiment

ERIC Educational Resources Information Center

Jantzi, Kevin L.; Wiltrakis, Susan; Wolf, Lauren; Weber, Anna; Cardinal, Josh; Krieter, Katie

2011-01-01

A critical factor for the increased nucleophilicity of the pyridine nitrogen in 4-(dimethylamino)pyridine (DMAP) is electron donation via resonance from the amino group into the aromatic ring that increases electron density on the pyridine nitrogen. To explore how important this resonance effect is, 4-(dimethylaminomethyl)pyridine (DMAMP) was…

An investigation of the impact of prolonged waiting times on blood donors in Ireland.

PubMed

McKeever, T; Sweeney, M R; Staines, A

2006-02-01

The aim of this study was to investigate the impact of prolonged queuing times on blood donors, by measuring their satisfaction levels, and positive and negative affects. As donation times have increased over the past number of years within the Irish Blood Transfusion Service, this is an important issue to examine in a climate where voluntary donors are becoming scarce and demands on people's time are increasing. Eighty-five blood donors were sampled from one urban and one rural blood donor clinic. The respondents conducted a questionnaire by means of face-to-face interview, while waiting in the clinic. The questionnaire contained the Positive and Negative Affect Scale (PANAS), and a waiting satisfaction scale. Both actual and perceived waiting times of the donors were noted. Waiting time was found to be negatively related to satisfaction. Inexperienced donors expressed higher levels of negative affect than experienced donors. Urban donors were significantly more satisfied than rural donors. There was a significant difference in perceived waiting time between lone donors and those queuing in a group, with those waiting alone perceiving their wait as shorter. While all respondents stated that they intended to donate again, over one-third stated that prolonged waiting times would be their most likely deterrent. However, only 15% stated that long queuing times might actually prevent them from donating in the future, and almost all respondents said that they would recommend donation to a friend, despite long queuing times. Although our results show that the respondents were not satisfied with current waiting times, it did not seem to affect their future intentions to donate. These findings provide some optimism for the future of blood donation in Ireland, as they suggest a strong sense of commitment to donation within the population sampled. Future research could explore the application of 'the service industry' approach to waiting times to blood donation clinics.

Palladium complexes of N-heterocyclic carbenes as catalysts for cross-coupling reactions--a synthetic chemist's perspective.

PubMed

Kantchev, Eric Assen B; O'Brien, Christopher J; Organ, Michael G

2007-01-01

Palladium-catalyzed C-C and C-N bond-forming reactions are among the most versatile and powerful synthetic methods. For the last 15 years, N-heterocyclic carbenes (NHCs) have enjoyed increasing popularity as ligands in Pd-mediated cross-coupling and related transformations because of their superior performance compared to the more traditional tertiary phosphanes. The strong sigma-electron-donating ability of NHCs renders oxidative insertion even in challenging substrates facile, while their steric bulk and particular topology is responsible for fast reductive elimination. The strong Pd-NHC bonds contribute to the high stability of the active species, even at low ligand/Pd ratios and high temperatures. With a number of commercially available, stable, user-friendly, and powerful NHC-Pd precatalysts, the goal of a universal cross-coupling catalyst is within reach. This Review discusses the basics of Pd-NHC chemistry to understand the peculiarities of these catalysts and then gives a critical discussion on their application in C-C and C-N cross-coupling as well as carbopalladation reactions.

Combined molecular and periodic DFT analysis of the adsorption of co macrocycles on graphene.

PubMed

Calborean, Adrian; Morari, Cristian; Maldivi, Pascale

2018-01-15

The molecular doping of graphene with π-stacked conjugated molecules has been widely studied during the last 10 years, both experimentally or using first-principle calculations, mainly with strongly acceptor or donor molecules. Macrocyclic metal complexes have been far less studied and their behavior on graphene is less clear-cut. The present density functional theory study of cobalt porphyrin and phthalocyanine adsorbed on monolayer or bilayer graphene allows to compare the outcomes of two models, either a finite-sized flake of graphene or an infinite 2D material using periodic calculations. The electronic structures yielded by both models are compared, with a focus on the density of states around the Fermi level. Apart from the crucial choice of calculation conditions, this investigation also shows that unlike strongly donating or accepting organic dopants, these macrocycles do not induce a significant doping of the graphene sheet and that a finite size model of graphene flake may be confidently used for most modeling purposes. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Preparation, structure, and unique redox properties of mono-, bis-, and Tris(diarylmethylene)-1,3,5-trithianes and related compounds

PubMed

Suzuki; Yoshino; Nishida; Ohkita; Tsuji

2000-09-08

A series of 1,3,5-trithianes 1-3 having diarylmethylene units were designed as novel electron donors giving highly colored cationic species upon oxidation. They were prepared along with the dithiane and dithiazine derivatives 4-6 by the reactions of lithiated heterocycles with diaryl ketones followed by dehydration. Voltammetric analyses indicate that a large structural change and/or transannular bonding are induced during their electrochemical oxidation. Mono(diarylmethylene) derivative 1a exhibits electrochromism with vivid change in color from faintly yellow to deep blue with concomitant rotation around the exocyclic bond. Both of the strongly colored salts obtained upon oxidation of 2,4-bis- and 2,4,6-tris(diarylmethylene)-1,3,5-trithianes (2aa and 3) consist of the dications with a 1,2,4-trithiane ring, suggesting the easy skeletal rearrangement of the transannular dications with a trithiabicylo[3.1.0]hexane ring. Upon reduction of these salts were obtained bright yellow 12 and 13, respectively, with high electron-donating properties due to the tetraarylbutadiene-type conjugation, thus giving another class of electrochromic compounds.

Reaction of cyanide with cytochrome ba3 from Thermus thermophilus: spectroscopic characterization of the Fe(II)a3-CN.Cu(II)B-CN complex suggests four 14N atoms are coordinated to CuB.

PubMed Central

Surerus, K K; Oertling, W A; Fan, C; Gurbiel, R J; Einarsdóttir, O; Antholine, W E; Dyer, R B; Hoffman, B M; Woodruff, W H; Fee, J A

1992-01-01

Cytochrome ba3 from Thermus thermophilus reacts slowly with excess HCN at pH 7.4 to create a form of the enzyme in which CuA, cytochrome b, and CuB remain oxidized, while cytochrome a3 is reduced by one electron, presumably with the formation of cyanogen. We have examined this form of the enzyme by UV-visible, resonance Raman, EPR, and electron nuclear double resonance spectroscopies in conjunction with permutations of 13C- and 15N-labeled cyanide. The results support a model in which one CN- binds through the carbon atom to ferrous a3, supporting a low-spin (S = 0) configuration on the Fe; bridging by this cyanide to the CuB is weak or absent. Four 14N atoms, presumably donated by histidine residues of the protein, provide a strong equatorial ligand field about CuB; a second CN- is coordinated through the carbon atom to CuB in an axial position. PMID:1314380

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

Babucci, Melike; Fang, Chia -Yu; Hoffman, Adam S.

1,3-Dialkylimidazolium ionic liquid coatings act as electron donors, increasing the selectivity for partial hydrogenation of 1,3-butadiene catalyzed by iridium complexes supported on high-surface-area γ-Al 2O 3. High-energy-resolution fluorescence detection X-ray absorption near-edge structure (HERFD XANES) measurements quantify the electron donation and are correlated with the catalytic activity and selectivity. Furthermore, the results demonstrate broad opportunities to tune electronic environments and catalytic properties of atomically dispersed supported metal catalysts.

36 CFR § 1256.24 - How long may access to some records be denied?

Code of Federal Regulations, 2013 CFR

2013-07-01

... RECORDS ADMINISTRATION PUBLIC AVAILABILITY AND USE ACCESS TO RECORDS AND DONATED HISTORICAL MATERIALS... of the records in which you are interested available. In the case of electronic structured databases...

Religious aspects of organ transplantation.

PubMed

Bruzzone, P

2008-05-01

No religion formally forbid donation or receipt of organs or is against transplantation from living or deceased donors. Only some orthodox jews may have religious objections to "opting in." However, transplantation from deceased donors may be discouraged by Native Americans, Roma Gypsies, Confucians, Shintoists, and some Orthodox rabbis. Some South Asia Muslim ulemas (scholars) and muftis (jurists) oppose donation from human living and deceased donors because the human body is an "amanat" (trusteeship) from God and must not be desecrated following death, but they encourage xenotransplantation research. No religion formally obliges one to donate or refuse organs. No religion formally obliges one to consider cadaveric organs "a societal resource" or considers organ donation "a religious duty" (except some rabbis and isolated Muslim and Christian scholars) No religion has a formal position on "bonus points," which is priority on the waiting list. Living organ donation is strongly encouraged only between jesus christians (15 of 28 jesus christians worldwide have donated a kidney). No religion forbid this practice. Directed organ donation to people of the same religion has been proposed only by some Orthodox Jews and some Islamic Ulemas/Muftis. Only some Muslim Ulemas/Muftis and some Asian religions may prefer living donation over cadaveric donation. No religion prefers cadaveric over living donation. No religion formally forbid non-heart-beating donors (nhbd) cadaveric donation or cross-over donation. Due to the sacrad of human life, the Catholic Church is against donation from anencephalic donors or after active euthanasia. No religion formally forbid xenotransplantation. Addressing the participants of the First International Congress of the Society for Organ Sharing in 1991, Pope John Paul II said "There are many questions of an ethical, legal and social nature which need to be more deeply investigated. There are even shameful abuses which call for determined action on the part of medical association and donor societies, and especially of competent legislative bodies" and later on "In effect, the human body is always a personal body, the body of a person. The body cannot be treated as a merely physical or biological entity, nor can its organs and tissues ever be used as item for sale or exchange". Addressing the participants at the XVIII International Congress of the Transplantation Society in 2000, Pope John Paul II said "Accordingly, any procedure which tends to commercialize human organs or to consider them as items of exchange or trade must be considered morally unacceptable, because to use the body as an object is to violate the dignity of the human person" and later on added "The criteria for assigning donated organs should in no way be discriminatory (i.e. based on age, sex, race, religion, social standing, etc.) or utilitarian (i.e. based on work capacity, social usefulness, etc.)." To conclude, according to the Catechism of the Catholic Church Compendium signed by Pope Benedict XVI on june 28, 2005, 476. Are allowed transplantation and organ donation, before and after death? Organ transplantation is morally acceptable with the consent of the donor and without excessive risks for him/her. For the noble act of organ donation after death, the real death of the donor must be fully ascertained.

CO adsorption on (111) and (100) surfaces of the Pt sub 3 Ti alloy. Evidence for parallel binding and strong activation of CO

NASA Technical Reports Server (NTRS)

Mehandru, S. P.; Anderson, A. B.; Ross, P. N.

1985-01-01

The CO adsorption on a 40 atom cluster model of the (111) surface and a 36 atom cluster model of the (100) surface of the Pt3Ti alloy was studied. Parallel binding to high coordinate sites associated with Ti and low CO bond scission barriers are predicted for both surfaces. The binding of CO to Pt sites occurs in an upright orientation. These orientations are a consequence of the nature of the CO pi donation interactions with the surface. On the Ti sites the orbitals donate to the nearly empty Ti 3d band and the antibonding counterpart orbitals are empty. On the Pt sites, however, they are in the filled Pt 5d region of the alloy band, which causes CO to bond in a vertical orientation by 5 delta donation from the carbon end.

A new perspective on the incentive-blood donation relationship: partnership, congruency, and affirmation of competence.

PubMed

Chmielewski, Danielle; Bove, Liliana L; Lei, Jing; Neville, Ben; Nagpal, Anish

2012-09-01

The Motivation Crowding-out Theory suggests that incentives undermine intrinsic motivation and thus blood donation behavior. While there is strong evidence showing the negative relationship between monetary incentives and blood donation, findings on the effect of nonmonetary incentives are mixed. Set in a voluntary, nonremunerated environment, this study explores aspects of the nonmonetary incentive-blood donation relationship not captured by the crowding-out hypothesis. In-depth interviews were conducted to explore donors' attitudes toward nonmonetary incentives currently used or considered by the Australian Red Cross Blood Service (Blood Service). Transcripts were analyzed using an inductive, thematic approach. Of the nonmonetary incentives examined (i.e., health screening tests, branded tokens, paid time off work, recognition of key milestones, and postdonation refreshments), none were found to crowd out intrinsic motivation, although not all were viewed favorably. Donors who viewed branded tokens negatively considered the cost implications for the Blood Service, while donors who responded positively considered the public benefit of tokens in raising the profile of the Blood Service. Other nonmonetary incentives-paid time off work, postdonation refreshments, and health screening tests-were viewed positively because donors perceived them to be congruent to the effort expended in donating blood. Finally, donors expressed a preference for private over public recognition when acknowledging significant contributions. When operating in a voluntary, nonremunerated environment, blood services should view donors as supply partners rather than customers, only consider nonmonetary incentives that are congruent with the act of donation, and provide private rather than public recognition of key milestones. © 2012 American Association of Blood Banks.

Could the organ shortage ever be met?

PubMed

Levitt, Mairi

2015-01-01

The organ shortage is commonly presented as having a clear solution, increase the number of organs donated and the problem will be solved. In the light of the Northern Ireland Assembly's consultation on moving to an opt-out organ donor register this article focuses on the social factors and complexities which impact strongly on both the supply of, and demand for, transplantable organs. Judging by the experience of other countries presumed consent systems may or may not increase donations but have not met demand. Donation rates have risen considerably in all parts of the UK recently but there is also an increasing demand for organs. Looking at international donation rates and attitudes, future demand for organs and education on donation, the question is whether the organ shortage could ever be met. The increase in longevity, in rates of diabetes and obesity and in alcohol related liver disease all contribute both to increased demand for transplants, and re-transplants, and a reduction in the number of usable organs. It is unlikely that demand could ever be met, since, if supply was unlimited, the focus would move to financial resources and competing demands on the health care budget in a publicly funded health system. These factors point to the need to focus on ways of reducing, or at least stabilizing, demand where lifestyle factors contribute to the underlying disease.

Thermally activated delayed fluorescence of a Zr-based metal–organic framework

DOE PAGES

Mieno, H.; Kabe, R.; Allendorf, M. D.; ...

2017-12-22

Here, the first metal–organic framework exhibiting thermally activated delayed fluorescence (TADF) was developed. The zirconium-based framework (UiO-68-dpa) uses a newly designed linker composed of a terphenyl backbone, an electron-accepting carboxyl group, and an electron-donating diphenylamine and exhibits green TADF emission with a photoluminescence quantum yield of 30% and high thermal stability.

Formation of tyrosine radicals in photosystem II under far-red illumination.

PubMed

Ahmadova, Nigar; Mamedov, Fikret

2018-04-01

Photosystem II (PS II) contains two redox-active tyrosine residues on the donor side at symmetrical positions to the primary donor, P 680 . Tyr Z , part of the water-oxidizing complex, is a preferential fast electron donor while Tyr D is a slow auxiliary donor to P 680 + . We used PS II membranes from spinach which were depleted of the water oxidation complex (Mn-depleted PS II) to study electron donation from both tyrosines by time-resolved EPR spectroscopy under visible and far-red continuous light and laser flash illumination. Our results show that under both illumination regimes, oxidation of Tyr D occurs via equilibrium with Tyr Z • at pH 4.7 and 6.3. At pH 8.5 direct Tyr D oxidation by P 680 + occurs in the majority of the PS II centers. Under continuous far-red light illumination these reactions were less effective but still possible. Different photochemical steps were considered to explain the far-red light-induced electron donation from tyrosines and localization of the primary electron hole (P 680 + ) on the Chl D1 in Mn-depleted PS II after the far-red light-induced charge separation at room temperature is suggested.

Oxidative versus Non-oxidative Decarboxylation of Amino Acids: Conditions for the Preferential Formation of Either Strecker Aldehydes or Amines in Amino Acid/Lipid-Derived Reactive Carbonyl Model Systems.

PubMed

Zamora, Rosario; León, M Mercedes; Hidalgo, Francisco J

2015-09-16

Comparative formation of both 2-phenylethylamine and phenylacetaldehyde as a consequence of phenylalanine degradation by carbonyl compounds was studied in an attempt to understand if the amine/aldehyde ratio can be changed as a function of reaction conditions. The assayed carbonyl compounds were selected because of the presence in the chain of both electron-donating and electron-withdrawing groups and included alkenals, alkadienals, epoxyalkenals, oxoalkenals, and hydroxyalkenals as well as lipid hydroperoxides. The obtained results showed that the 2-phenylethylamine/phenylacetaldehyde ratio depended upon both the carbonyls and the reaction conditions. Thus, it can be increased using electron-donating groups in the chain of the carbonyl compound, small amounts of carbonyl compound, low oxygen content, increasing the pH, or increasing the temperature at pH 6. Opposed conditions (use of electron-withdrawing groups in the chain of the carbonyl compound, large amounts of carbonyl compound, high oxygen contents, low pH values, and increasing temperatures at low pH values) would decrease the 2-phenylethylamine/phenylacetaldehyde ratio, and the formation of aldehydes over amines in amino acid degradations would be favored.

Differential impact of amino acids on OXPHOS system activity following carbohydrate starvation in Arabidopsis cell suspensions.

PubMed

Cavalcanti, João Henrique F; Quinhones, Carla G S; Schertl, Peter; Brito, Danielle S; Eubel, Holger; Hildebrandt, Tatjana; Nunes-Nesi, Adriano; Braun, Hans-Peter; Araújo, Wagner L

2017-12-01

Plant respiration mostly depends on the activity of glycolysis and the oxidation of organic acids in the tricarboxylic acid cycle to synthesize ATP. However, during stress situations plant cells also use amino acids as alternative substrates to donate electrons through the electron-transfer flavoprotein (ETF)/ETF:ubiquinone oxidoreductase (ETF/ETFQO) complex to the mitochondrial electron transport chain (mETC). Given this, we investigated changes of the oxidative phosphorylation (OXPHOS) system in Arabidopsis thaliana cell culture under carbohydrate starvation supplied with a range of amino acids. Induction of isovaleryl-CoA dehydrogenase (IVDH) activity was observed under carbohydrate starvation which was associated with increased amounts of IVDH protein detected by immunoblotting. Furthermore, activities of the protein complexes of the mETC were reduced under carbohydrate starvation. We also observed that OXPHOS system activity behavior is differently affected by different amino acids and that proteins associated with amino acids catabolism are upregulated in cells following carbohydrate starvation. Collectively, our results support the contention that ETF/ETFQO is an essential pathway to donate electrons to the mETC and that amino acids are alternative substrates to maintain respiration under carbohydrate starvation. © 2017 Scandinavian Plant Physiology Society.

Adsorption characteristics of green 5-arylaminomethylene pyrimidine-2,4,6-triones on mild steel surface in acidic medium: Experimental and computational approach

NASA Astrophysics Data System (ADS)

Verma, Chandrabhan; Olasunkanmi, Lukman O.; Ebenso, Eno E.; Quraishi, M. A.

2018-03-01

The effect of electron withdrawing nitro (-NO2) and electron releasing hydroxyl (-OH) groups on corrosion inhibition potentials of 5-arylaminomethylenepyrimidine-2,4,6-trione (AMP) had been studied. Four AMPs tagged AMP-1, AMP-2, AMP-3 and AMP-4 were studied for their ability to inhibit mild steel corrosion in 1 M HCl using experimental and theoretical methods. Gravimetric results showed that inhibition efficiency of the studied inhibitors increases with increasing concentration. The results further revealed that that electron withdrawing nitro (-NO2) group decreases the inhibition efficiency of AMP, while electron donating hydroxyl (-OH) group increases the inhibition efficiency of AMP. SEM and AFM studies showed that the studied compounds inhibit mild steel corrosion by adsorbing at the metal/electrolyte interface and their adsorption obeyed the Temkin adsorption isotherm. Potentiodynamic polarization study revealed that studied inhibitors act as mixed type inhibitors with predominant effect on cathodic reaction. The inhibitive strength of the compounds might have direct relationship electron donating ability of the molecules as revealed by quantum chemical parameters. The order of interaction energies derived from Monte Carlo simulations is AMP-4 > AMP-3 > AMP-2 > AMP-1, which is in agreement with the order of inhibition efficiencies obtained from experimental measurements.

The unexpected roles of σ and π orbitals in electron donor and acceptor group effects on the 13C NMR chemical shifts in substituted benzenes† †Electronic supplementary information (ESI) available: Experimental 13C NMR chemical shifts, individual components of the 13C NMR shielding tensor, lists and graphics of NLMO contributions, and tables of NLMO properties. See DOI: 10.1039/c7sc02163a Click here for additional data file.

PubMed Central

Viesser, Renan V.

2017-01-01

Effects of electron-donating (R = NH2) and electron-withdrawing (R = NO2) groups on 13C NMR chemical shifts in R-substituted benzene are investigated by molecular orbital analyses. The 13C shift substituent effect in ortho, meta, and para position is determined by the σ bonding orbitals in the aryl ring. The π orbitals do not explain the substituent effects in the NMR spectrum as conventionally suggested in textbooks. The familiar electron donating and withdrawing effects on the π system by NH2 and NO2 substituents induce changes in the σ orbital framework, and the 13C chemical shifts follow the trends induced in the σ orbitals. There is an implicit dependence of the σ orbital NMR shift contributions on the π framework, via unoccupied π* orbitals, due to the fact that the nuclear shielding is a response property. PMID:28989684

Reduction of mitomycin C is catalysed by human recombinant NRH:quinone oxidoreductase 2 using reduced nicotinamide adenine dinucleotide as an electron donating co-factor

PubMed Central

Jamieson, D; Tung, A T Y; Knox, R J; Boddy, A V

2006-01-01

NRH:Quinone Oxidoreductase 2 (NQO2) has been described as having no enzymatic activity with nicotinamide adenine dinucleotide (NADH) or NADPH as electron donating cosubstrates. Mitomycin C (MMC) is both a substrate for and a mechanistic inhibitor of the NQO2 homologue NQO1. NRH:quinone oxidoreductase 2 catalysed the reduction of MMC at pH 5.8 with NADH as a co-factor. This reaction results in species that inhibit the NQO2-mediated metabolism of CB1954. In addition, MMC caused an increase in DNA cross-links in a cell line transfected to overexpress NQO2 to an extent comparable to that observed with an isogenic NQO1-expressing cell line. These data indicate that NQO2 may contribute to the metabolism of MMC to cytotoxic species. PMID:17031400

From motivation to acceptability: a survey of public attitudes towards organ donation in Denmark.

PubMed

Nordfalk, Francisca; Olejaz, Maria; Jensen, Anja M B; Skovgaard, Lea Larsen; Hoeyer, Klaus

2016-01-01

Over the past three decades, public attitudes to organ donation have been a subject of numerous studies focusing on donor motivation. Here, we present a fresh approach. We suggest focusing on public acceptability instead of motivation. The point is to understand public attitudes well enough to avoid risking public support for organ transplantation. We conducted the study in Denmark because there have been significant developments in public attitudes to organ donation in this country. In the 1990s, Denmark was a country with very low public support for organ donation and Denmark was the last country in Europe to introduce brain death as a legal criterion of death, whereas today Eurobarometer surveys rate Denmark as one of the European countries with the highest support for deceased organ donation from brain dead donors. We conducted a telephone survey in Denmark (N = 1195). A questionnaire was developed on the basis of preceding qualitative studies and pilot testing and included reuse of one item from earlier surveys to facilitate historical comparison. The analysis of the data was carried out using IBM SPSS Statistics 22 and focused on descriptive statistics. A clear majority of 91.9 % are positive or very positive towards organ donation; 85.8 % like the idea of their body being used after their death, 85.0 % is willing to donate their own organs, 82.1 % to donate their tissue and only 2.3 % find that too much has been done to promote organ donation. There is limited support for monetary incentives for organ donation (5.8 %) and presumed consent (30.4 %), while a majority (63.9 %) supports making it mandatory to register a personal decision. Religious self-identification has limited impact on attitudes. We can identify a shift over the past three decades from marked opposition to organ transplantation to strong support as well as a pattern in the contemporary public attitudes, which can help explain what is central to public acceptability: self-determination. Policies fostering choice are met with a majority of positive attitudes, while presumed consent and monetary incentives are met with more negative attitudes. Our approach calls for comparative studies in other countries to generate a better overall understanding of the conditions of acceptability, which need to be in place to ensure the long-term social robustness of organ donation and thereby safeguard this important medical technology.

Understanding Anionic "Ligandless" Palladium Species in the Mizoroki-Heck Reaction.

PubMed

Schroeter, Felix; Strassner, Thomas

2018-05-07

The anionic complex [NBu 4 ][Pd(DMSO)Cl 3 ], as a "ligandless" system, was shown to be an active catalyst in the Mizoroki-Heck coupling of aryl chlorides in the absence of strongly σ-donating ligands. To investigate the experimentally observed influence of halides and the amount of water on the catalytic activity, we employed a combination of experiments and theoretical calculations. The presence of water was shown to be critical for the formation of the active palladium(0) species by oxidation of in situ generated tributylamine. Oxidative addition to an anionic palladium(0) species was found to be the rate-determining step of the catalytic cycle. For the ensuing steps, both neutral and anionic pathways were considered. It was shown that, in the absence of strongly σ-donating neutral ligands, chloride ions stabilize the catalytic intermediates. Therefore, an anionic pathway is preferred, which explains the need for tetrabutylammonium chloride as an additive. The study of the influence of bromide ions on the catalytic activity revealed that the strongly exergonic displacement of the neutral substrates by bromide ions lowers the catalytic activity.

A plea for uniform European definitions for organ donor potential and family refusal rates.

PubMed

Jansen, Nichon E; Haase-Kromwijk, Bernadette J J M; van Leiden, Hendrik A; Weimar, Willem; Hoitsma, Andries J

2009-11-01

Conversion of potential organ donors to actual donors is negatively influenced by family refusals. Refusal rates differ strongly among countries. Is it possible to compare refusal rates in order to be able to learn from countries with the best practices? We searched in the literature for reviews of donor potential and refusal rates for organ donation in intensive care units. We found 14 articles pertinent to this study. There is an enormous diversity among the performed studies. The definitions of potential organ donors and family refusal differed substantially. We tried to re-calculate the refusal rates. This method failed because of the influence caused by the registered will on donation in the Donor Register. We therefore calculated the total refusal rate. This strategy was also less satisfactory considering possible influence of the legal consent system on the approach of family. Because of lack of uniform definitions, we can conclude that the refusal rates for organ donation can not be used for a sound comparison among countries. To be able to learn from well-performing countries, it is necessary to establish uniform definitions regarding organ donation and registration of all intensive care deaths.

Photoswitching Behavior of 5-Phenylazopyrimidines: In Situ Irradiation NMR and Optical Spectroscopy Combined with Theoretical Methods.

PubMed

Čechová, Lucie; Kind, Jonas; Dračínský, Martin; Filo, Juraj; Janeba, Zlatko; Thiele, Christina M; Cigáň, Marek; Procházková, Eliška

2018-05-11

The photoswitching behavior of 5-phenylazopyrimidines was investigated by optical methods and NMR spectroscopy with in situ irradiation sustained by mathematical modeling and DFT calculations. Irradiation of various compounds with electron-donating groups on the pyrimidine ring and substituents with electron-withdrawing as well as electron-donating substituent in the para-position of the phenyl ring were examined. All compounds could be successfully converted to the cis isomer; this isomerization and the subsequent thermal fading were studied. Switching cycles can be repeated without signs of photodegradation for most of the compounds, which makes them adept to molecular photoswitches. Interestingly, the chloro and cyano derivatives can be switched without UV light, which makes them vis(π → π*)-vis(n → π*) photoswitches. Surprisingly equal trans-to- cis photoisomerization quantum yields for π → π* and n → π* excitation indicate the blocking of the inversion pathway following π → π* excitation. In contrast to that, DFT computations suggest the inversion mechanism for the reverse thermal cis-to- trans isomerization of 5-phenylazopyrimidines.

Electronic-property dependent interactions between tetracycline and graphene nanomaterials in aqueous solution.

PubMed

He, Lin; Liu, Fei-Fei; Zhao, Mengyao; Qi, Zhen; Sun, Xuefei; Afzal, Muhammad Zaheer; Sun, Xiaomin; Li, Yanhui; Hao, Jingcheng; Wang, Shuguang

2018-04-01

Understanding the interactions between graphene nanomaterials (GNMs) and antibiotics in aqueous solution is critical to both the engineering applications of GNMs and the assessment of their potential impact on the fate and transport of antibiotics in the aquatic environment. In this study, adsorption of one common antibiotic, tetracycline, by graphene oxide (GO) and reduced graphene oxide (RGO) was examined with multi-walled carbon nanotubes (MWCNTs) and graphite as comparison. The results showed that the tetracycline adsorption capacity by the four selected carbonaceous materials on the unit mass basis followed an order of GO>RGO>MWCNTs>graphite. Upon normalization by surface area, graphite, RGO and MWCNTs had almost the same high tetracycline adsorption affinity while GO exhibited the lowest. We proposed π-electron-property dependent interaction mechanisms to explain the observed different adsorption behaviors. Density functional theory (DFT) calculations suggested that the oxygen-containing functional groups on GO surface reduced its π-electron-donating ability, and thus decreased the π-based interactions between tetracycline and GO surface. Comparison of adsorption efficiency at different pH indicated that electrostatic interaction also played an important role in tetracycline-GO interactions. Site energy analysis confirmed a highly heterogeneous distribution of the binding sites and strong tetracycline binding affinity of GO surface. Copyright © 2017. Published by Elsevier B.V.

Trans influence on the rate of reductive elimination. Reductive elimination of amines from isomeric arylpalladium amides with unsymmetrical coordination spheres.

PubMed

Yamashita, Makoto; Cuevas Vicario, Jose V; Hartwig, John F

2003-12-31

To determine the trans effect on the rates of reductive eliminations from arylpalladium(II) amido complexes, the reactions of arylpalladium amido complexes bearing symmetrical and unsymmetrical DPPF (DPPF = bis(diphenylphosphino)ferrocene) derivatives were studied. THF solutions of LPd(Ar)(NMeAr') (L = DPPF, DPPF-OMe, DPPF-CF3, DPPF-OMe,Ph, DPPF-Ph,CF3, and DPPF-OMe,CF3; Ar = C6H4-4-CF3; Ar' = C6H4-4-CH3, Ph, and C6H4-4-OMe) underwent C-N bond forming reductive elimination at -15 C to form the corresponding N-methyldiarylamine in high yield. Complexes ligated by symmetrical DPPF derivatives with electron-withdrawing substituents on the DPPF aryl groups underwent reductive elimination faster than complexes ligated by symmetrical DPPF derivatives with electron-donating substituents on the ligand aryl groups. Studies of arylpalladium amido complexes containing unsymmetrical DPPF ligands revealed several trends. First, the complex with the weaker donor trans to nitrogen and the stronger donor trans to the palladium-bound aryl group underwent reductive elimination faster than the regioisomeric complex with the stronger donor trans to nitrogen and the weaker donor trans to the palladium-bound aryl group. Second, the effect of varying the substituents on the phosphorus donor trans to the nitrogen was larger than the effect of varying the substituents on the phosphorus donor trans to the palladium-bound aryl group. Third, the difference in rate between the isomeric arylpalladium amido complexes was similar in magnitude to the differences in rates resulting from conventional variation of substituents on the symmetric phosphine ligands. This result suggests that the geometry of the complex is equal in importance to the donating ability of the dative ligands. The ratio of the differences in rates of reaction of the isomeric complexes was similar to the relative populations of the two geometric isomers. This result and consideration of transition state geometries suggest that the reaction rates are controlled more by substituent effects on ground state stability than on transition state energies. In addition, variation of the aryl group at the amido nitrogen showed systematically that complexes with more electron-donating groups at nitrogen undergo faster reductive elimination than those with less electron-donating groups at nitrogen.

Hexadecylamine Adsorption at the Iron Oxide–Oil Interface

PubMed Central

2013-01-01

The adsorption behavior of a model additive, hexadecylamine, onto an iron surface from hexadecane oil has been characterized using polarized neutron reflectometry, sum-frequency generation spectroscopy, solution depletion isotherm, and X-ray photoelectron spectroscopy (XPS). The amine showed a strong affinity for the metal surface, forming a dense monolayer at relatively low concentrations; a layer thickness of 16 (±3) Å at low concentrations, increasing to 20 (±3) Å at greater amine concentrations, was determined from the neutron data. These thicknesses suggest that the molecules in the layer are tilted. Adsorption was also indicated by sum-frequency generation spectroscopy and XPS, the latter indicating that the most dominant amine–surface interaction was via electron donation from the nitrogen lone pair to the positively charged iron ions. Sum-frequency generation spectroscopy was used to determine the alkyl chain conformation order and orientation on the surface. PMID:24106786

Stereodivergent Mannich reaction of bis(trimethylsilyl)ketene acetals with N-tert-butanesulfinyl imines by Lewis acid or Lewis base activation, a one-pot protocol to obtain chiral β-amino acids.

PubMed

Cantú-Reyes, Margarita; Alvarado-Beltrán, Isabel; Ballinas-Indilí, Ricardo; Álvarez-Toledano, Cecilio; Hernández-Rodríguez, Marcos

2017-09-20

We report a one-pot synthesis of chiral β 2,2,3 -amino acids by the Mannich addition of bistrimethylsilyl ketene acetals to N-tert-butanesulfinyl imines followed by the removal of the chiral auxiliary. The synthesis and isolation of pure β-amino acid hydrochlorides were conducted under mild conditions, without strong bases and this method is operationally simple. The stereoselective reaction was promoted by two different activation methods that lead to different stereoisomers: (1) Lewis Acid (LA) catalysis with boron trifluoride diethyl etherate and (2) Lewis Base (LB) catalysis with tetrabutylammonium difluorotriphenylsilicate. The reaction presented good diastereoselectivity with LB activation and moderate to good dr with LA catalysis. The exceptions in both protocols were imines with electron donating groups in the aromatic ring.

Nanoscale arrays of antimony telluride single crystals by selective chemical vapor deposition

PubMed Central

Huang, Ruomeng; Benjamin, Sophie L.; Gurnani, Chitra; Wang, Yudong; Hector, Andrew L.; Levason, William; Reid, Gillian; De Groot, C. H. (Kees)

2016-01-01

Arrays of individual single nanocrystals of Sb2Te3 have been formed using selective chemical vapor deposition (CVD) from a single source precursor. Crystals are self-assembled reproducibly in confined spaces of 100 nm diameter with pitch down to 500 nm. The distribution of crystallite sizes across the arrays is very narrow (standard deviation of 15%) and is affected by both the hole diameter and the array pitch. The preferred growth of the crystals in the <1 1 0> orientation along the diagonal of the square holes strongly indicates that the diffusion of adatoms results in a near thermodynamic equilibrium growth mechanism of the nuclei. A clear relationship between electrical resistivity and selectivity is established across a range of metal selenides and tellurides, showing that conductive materials result in more selective growth and suggesting that electron donation is of critical importance for selective deposition. PMID:27283116

Molecules with enhanced electronic polarizabilities based on defect-like states in conjugated polymers

NASA Technical Reports Server (NTRS)

Beratan, David N. (Inventor)

1991-01-01

Highly conjugated organic polymers typically have large non-resonant electronic susceptibilities, which give the molecules unusual optical properties. To enhance these properties, defects are introduced into the polymer chain. Examples include light doping of the conjugated polymer and synthesis, conjugated polymers which incorporate either electron donating or accepting groups, and conjugated polymers which contain a photoexcitable species capable of reversibly transferring its electron to an acceptor. Such defects in the chain permit enhancement of the second hyperpolarizability by at least an order of magnitude.

Approaches for optimizing the first electronic hyperpolarizability of conjugated organic molecules

NASA Technical Reports Server (NTRS)

Marder, S. R.; Beratan, D. N.; Cheng, L.-T.

1991-01-01

Conjugated organic molecules with electron-donating and -accepting moieties can exhibit large electronic second-order nonlinearities, or first hyperpolarizabilities, beta. The present two-state, four-orbital independent-electron analysis of beta leads to the prediction that its absolute value will be maximized at a combination of donor and acceptor strengths for a given conjugated bridge. Molecular design strategies for beta optimization are proposed which give attention to the energetic manipulations of the bridge states. Experimental results have been obtained which support the validity of this approach.

Electron shuttles in biotechnology.

PubMed

Watanabe, Kazuya; Manefield, Mike; Lee, Matthew; Kouzuma, Atsushi

2009-12-01

Electron-shuttling compounds (electron shuttles [ESs], or redox mediators) are essential components in intracellular electron transfer, while microbes also utilize self-produced and naturally present ESs for extracellular electron transfer. These compounds assist in microbial energy metabolism by facilitating electron transfer between microbes, from electron-donating substances to microbes, and/or from microbes to electron-accepting substances. Artificially supplemented ESs can create new routes of electron flow in the microbial energy metabolism, thereby opening up new possibilities for the application of microbes to biotechnology processes. Typical examples of such processes include halogenated-organics bioremediation, azo-dye decolorization, and microbial fuel cells. Herein we suggest that ESs can be applied widely to create new microbial biotechnology processes.

Cyberskepticism: The Mind’s Firewall

DTIC Science & Technology

2008-01-01

phonebook; BitTorrent; iTunes ; YouTube; forums; chat rooms; dating; Craig’s List; donate; blog/vlog; video games; e-invitations; e- cards ; weather...computer. Real-world romance techniques on the Internet have produced some very innovative cyber deception techniques. Valentine cards sent...electronically are one technique designed to enhance romance. In 2006 electronic Valentine cards were sent to unsuspecting people who opened them for various

p-Type semiconducting nickel oxide as an efficiency-enhancing anodal interfacial layer in bulk heterojunction solar cells

DOEpatents

Irwin, Michael D; Buchholz, Donald B; Marks, Tobin J; Chang, Robert P. H.

2014-11-25

The present invention, in one aspect, relates to a solar cell. In one embodiment, the solar cell includes an anode, a p-type semiconductor layer formed on the anode, and an active organic layer formed on the p-type semiconductor layer, where the active organic layer has an electron-donating organic material and an electron-accepting organic material.

Bonding in tris(. eta. sup 5 -cyclopentadienyl) actinide complexes. 3. Interaction of. pi. -neutral,. pi. -acidic, and. pi. -basic ligands with (. eta. sup 5 -C sub 5 H sub 5 ) sub 3 U sup 1

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

Bursten, B.E.; Rhodes, L.F.; Strittmater

1989-04-12

A qualitative treatment of the bonding in Cp{sub 3}M (Cp = {eta}{sup 5}-C{sub 5}H{sub 5}) compounds under C{sub 3{upsilon}} symmetry reveals that the Cp{sub 3}{sup 3{minus}} ligand field contains a high-lying a{sub 2} orbital which is restricted by symmetry to interact only with metals that contain f orbitals. Quantitative investigation of the electronic structure of 5f{sup 3} Cp{sub 3}U via X{alpha}-SW molecular orbital calculations with quasi-relativistic corrections reveals that the Cp ligands donate electron density primarily into the U 6d orbitals while the three principally metal-based valence electrons are housed in the 5f orbitals. Electronic structure calculations of Cl{sub 3}Umore » show that although Cl can be considered isolobal with Cp, it is a poorer donor ligand. Calculations of Cp{sub 3}U bonded to a fourth ligand L (L = H, CO, NO, OH) indicate that the {sigma}-bonding framework is essentially the same for {pi}-neutral (H), {pi}-acidic (CO, NO), or {pi}-basic (OH) ligands: Electron density is donated from the {sigma} orbital of the fourth ligand into a uranium orbital that is primarily 6d{sub z{sup 2}} in character with minor contributions from the 5f{sub z{sup 3}} orbital, the 7p{sub z} orbital, and the 7s orbital. In the {pi}-bonding framework, the U 5f orbitals are responsible for back-donation into the {pi}* orbitals of CO an NO, while acceptance of electron density from the {pi} orbitals of OH involves the U 6d orbitals and, to a lesser extent, the U 5f orbitals. The bonding scheme of Cp{sub 3}UNO suggests that this molecule may prove to be a rather unusual example of a linear NO{sup {minus}} ligand.« less

From altruism to monetisation: Australian women's ideas about money, ethics and research eggs.

PubMed

Waldby, Catherine; Kerridge, Ian; Boulos, Margaret; Carroll, Katherine

2013-10-01

We report the results of a qualitative study carried out in metropolitan Australia between 2009 and 2011 that canvassed the issue of payment for research oöcyte donation with participants drawn from three potential donor groups; fertility patients, reproductive donors and young, non-patient women. Research oöcytes are controversial tissues because women around the world have proved largely unwilling to donate them altruistically. In the ensuing international debate about procurement, the issue of money and its appropriate and inappropriate uses in tissue donation has taken centre stage. While there is now an abundance of expert commentary on this matter, there are almost no studies that probe this issue with potential donor populations. Our study asked the three groups of women about their understandings of altruistic, reimbursed, subsidised, compensated and paid donation for both reproductive and research eggs. We identify a resistance to the introduction of money into the sphere of reproductive donation, which the majority of respondents felt should remain an area of personalised gift relations. In the area of research donation we find a strong relationship between degrees of liquidity (the extent to which money is constrained or unconstrained) and a sense of ethical appropriateness. We also describe a culturally specific sense of fairness and equity among participants, associated with the relatively high public subsidisation of fertility treatment in Australia, which they used to benchmark their sense of appropriate and inappropriate uses of money. While the participant responses reflect the regulatory environment in Australia, particularly the absence of a US style market in reproductive oöcytes, they also make an important contribution to the global debate. Copyright © 2013 Elsevier Ltd. All rights reserved.

On the similarity of the bonding in NiS and NiO

NASA Technical Reports Server (NTRS)

Bauschlicher, C. W., Jr.

1985-01-01

The bonding in NiS is found to be quite similar to that in NiO, having an ionic contribution arising from the donation of the Ni 4s electron to the S atom and a covalent component arising from bonds between the Ni 3d and the S 3p. The one-electron d bonds are found to be of equal strength for NiO and NiS, but the two-electron d bonds are weaker for NiS.

Tuning the Selectivity of Single-Site Supported Metal Catalysts with Ionic Liquids

DOE PAGES

Babucci, Melike; Fang, Chia -Yu; Hoffman, Adam S.; ...

2017-09-11

1,3-Dialkylimidazolium ionic liquid coatings act as electron donors, increasing the selectivity for partial hydrogenation of 1,3-butadiene catalyzed by iridium complexes supported on high-surface-area γ-Al 2O 3. High-energy-resolution fluorescence detection X-ray absorption near-edge structure (HERFD XANES) measurements quantify the electron donation and are correlated with the catalytic activity and selectivity. Furthermore, the results demonstrate broad opportunities to tune electronic environments and catalytic properties of atomically dispersed supported metal catalysts.

Donor and Recipient Views on Their Relationship in Living Kidney Donation: Thematic Synthesis of Qualitative Studies.

PubMed

Ralph, Angelique F; Butow, Phyllis; Hanson, Camilla S; Chadban, Steve J; Chapman, Jeremy R; Craig, Jonathan C; Kanellis, John; Luxton, Grant; Tong, Allison

2017-05-01

Many donors and recipients report an improved relationship after transplantation; however, tension, neglect, guilt, and proprietorial concern over the recipient can impede donor and recipient well-being and outcomes. We aimed to describe donor and recipient expectations and experiences of their relationship in the context of living kidney donation. Thematic synthesis of qualitative studies. Living kidney donors and recipients. Electronic databases were searched to October 2015. Thematic synthesis. From 40 studies involving 1,440 participants (889 donors and 551 recipients) from 13 countries, we identified 6 themes. "Burden of obligation" described the recipient's perpetual sense of duty to demonstrate gratitude to the donor. "Earning acceptance" was the expectation that donation would restore relationships. "Developing a unique connection" reflected the inexplicable bond that donor-recipient dyads developed postdonation. "Desiring attention" was expressed by donors who wanted recognition for the act of donation and were envious and resentful of the attention the recipient received. "Retaining kidney ownership" reflected the donor's inclination to ensure that the recipient protected "their" kidney. "Enhancing social participation" encompassed relieving both the caregiver from the constraints of dialysis and the recipient from increased involvement and contribution in family life. Non-English articles were excluded. Living kidney donation can strengthen donor-recipient relationships but may trigger or exacerbate unresolved angst, tension, jealousy, and resentment. Facilitating access to pre- and posttransplantation psychological support that addresses potential relationship changes may help donors and recipients better adjust to changes in the relationship dynamics, which in turn may contribute to improved psychosocial and transplantation outcomes following living kidney donation. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Physical origins of weak H{sub 2} binding on carbon nanostructures: Insight from ab initio studies of chemically functionalized graphene nanoribbons

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

Ulman, Kanchan; Bhaumik, Debarati; Wood, Brandon C.

2014-05-07

We have performed ab initio density functional theory calculations, incorporating London dispersion corrections, to study the absorption of molecular hydrogen on zigzag graphene nanoribbons whose edges have been functionalized by OH, NH{sub 2}, COOH, NO{sub 2}, or H{sub 2}PO{sub 3}. We find that hydrogen molecules always preferentially bind at or near the functionalized edge, and display induced dipole moments. Binding is generally enhanced by the presence of polar functional groups. The largest gains are observed for groups with oxygen lone pairs that can facilitate local charge reorganization, with the biggest single enhancement in adsorption energy found for “strong functionalization” bymore » H{sub 2}PO{sub 3} (115 meV/H{sub 2} versus 52 meV/H{sub 2} on bare graphene). We show that for binding on the “outer edge” near the functional group, the presence of the group can introduce appreciable contributions from Debye interactions and higher-order multipole electrostatic terms, in addition to the dominant London dispersion interactions. For those functional groups that contain the OH moiety, the adsorption energy is linearly proportional to the number of lone pairs on oxygen atoms. Mixed functionalization with two different functional groups on a graphene edge can also have a synergistic effect, particularly when electron-donating and electron-withdrawing groups are combined. For binding on the “inner edge” somewhat farther from the functional group, most of the binding again arises from London interactions; however, there is also significant charge redistribution in the π manifold, which directly reflects the electron donating or withdrawing capacity of the functional group. Our results offer insight into the specific origins of weak binding of gas molecules on graphene, and suggest that edge functionalization could perhaps be used in combination with other strategies to increase the uptake of hydrogen in graphene. They also have relevance for the storage of hydrogen in porous carbon materials, such as activated carbons.« less

Safety and frequency of whole blood donations from elderly donors.

PubMed

Müller-Steinhardt, M; Müller-Kuller, T; Weiss, C; Menzel, D; Wiesneth, M; Seifried, E; Klüter, H

2012-02-01

Within the coming decades, a steadily growing demand for blood products will face a shrinking blood donor population in many countries. After increasing the donor age of repeat donors for whole blood donation (WB) from 68 to 70 years in 2009 in our Blood Service, we investigated whether this is sufficient as a safe and effective strategy to sustain future blood supply. Between 1 March 2009 and 28 February 2011, WB donations from donors aged between 69 and 70 and their proportion of total donations in 2010 were determined. We analysed adverse reaction rates in donors with respect to sex and age and calculated mean annual donation frequencies. Of all invited donors, 32·5% responded and contributed 0·98% (men) and 0·56% (women) to all WB units collected in 2010. The overall and systemic adverse reaction rate per 1·000 WB donations declined by age [men: 1·10 (95%CI: 0·84-1·35) vs. 0 (0-0·8), P < 0·0001; 0·99 (0·75-1·23) vs. 0 (0-0·8), P < 0·0001 and women: 1·80 (1·46-2·14) vs. 1·12 (0·1-2·66), P < 0·0001; 1·47 (1·17-1·78) vs. 1·12 (-0·43-2·66), P = 0·0004]. Mean donation frequencies were strongly correlated with increasing age (men: r = 0·953, P < 0·0001; women: r = 0·913, P < 0·0001) with peak values for 70-year-old male: 2·53 ± 1·37 vs. 1·79 ± 1·05, P < 0·0001 and female donors: 2·15 ± 1·06 vs. 1·52 ± 0·78, P < 0·0001. Elderly donors have very low adverse reaction frequencies and are highly committed to donate blood. Thus, we consider donations from repeat donors aged 69-70 safe and suggest it a powerful short- to midterm strategy to, at least partially, overcome the challenges of the demographic change. © 2011 The Author(s). Vox Sanguinis © 2011 International Society of Blood Transfusion.

A reversible ratiometric sensor for intracellular Cu2+ imaging: metal coordination-altered FRET in a dual fluorophore hybrid.

PubMed

Chen, Yuncong; Zhu, Chengcheng; Cen, Jiajie; Li, Jing; He, Weijiang; Jiao, Yang; Guo, Zijian

2013-09-07

ICT fluorophore benzoxadiazole with its electron-donating group modified as a Cu(2+) chelator was conjugated with coumarin to construct a new ratiometric sensor with reversible intracellular Cu(2+) imaging ability.

Where does the electron go? The nature of ortho/para and meta group directing in electrophilic aromatic substitution

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

Liu, Shubin, E-mail: shubin@email.unc.edu

Electrophilic aromatic substitution as one of the most fundamental chemical processes is affected by atoms or groups already attached to the aromatic ring. The groups that promote substitution at the ortho/para or meta positions are, respectively, called ortho/para and meta directing groups, which are often characterized by their capability to donate electrons to or withdraw electrons from the ring. Though resonance and inductive effects have been employed in textbooks to explain this phenomenon, no satisfactory quantitative interpretation is available in the literature. Here, based on the theoretical framework we recently established in density functional reactivity theory (DFRT), where electrophilicity andmore » nucleophilicity are simultaneously quantified by the Hirshfeld charge, the nature of ortho/para and meta group directing is systematically investigated for a total of 85 systems. We find that regioselectivity of electrophilic attacks is determined by the Hirshfeld charge distribution on the aromatic ring. Ortho/para directing groups have most negative charges on the ortho/para positions, while meta directing groups often possess the largest negative charge on the meta position. Our results do not support that ortho/para directing groups are electron donors and meta directing groups are electron acceptors. Most neutral species we studied here are electron withdrawal in nature. Anionic systems are always electron donors. There are also electron donors serving as meta directing groups. We predicted ortho/para and meta group directing behaviors for a list of groups whose regioselectivity is previously unknown. In addition, strong linear correlations between the Hirshfeld charge and the highest occupied molecular orbital have been observed, providing the first link between the frontier molecular orbital theory and DFRT.« less

Structural features, kinetics and SAR study of radical scavenging and antioxidant activities of phenolic and anilinic compounds

PubMed Central

2013-01-01

Background Phenolic compounds are widely distributed in plant kingdom and constitute one of the most important classes of natural and synthetic antioxidants. In the present study fifty one natural and synthetic structurally variant phenolic, enolic and anilinic compounds were examined as antioxidants and radical scavengers against DPPH, hydroxyl and peroxyl radicals. The structural diversity of the used phenolic compounds includes monophenols with substituents frequently present in natural phenols e.g. alkyl, alkoxy, ester and carboxyl groups, besides many other electron donating and withdrawing groups, in addition to polyphenols with 1–3 hydroxyl groups and aminophenols. Some common groups e.g. alkyl, carboxyl, amino and second OH groups were incorporated in ortho, meta and para positions. Results SAR study indicates that the most important structural feature of phenolic compounds required to possess good antiradical and antioxidant activities is the presence of a second hydroxyl or an amino group in o- or p-position because of their strong electron donating effect in these positions and the formation of a stable quinone-like products upon two hydrogen-atom transfer process; otherwise, the presence of a number of alkoxy (in o or p-position) and /or alkyl groups (in o, m or p-position) should be present to stabilize the resulted phenoxyl radical and reach good activity. Anilines showed also similar structural feature requirements as phenols to achieve good activities, except o-diamines which gave low activity because of the high energy of the resulted 1,2-dimine product upon the 2H-transfer process. Enols with ene-1,2-diol structure undergo the same process and give good activity. Good correlations were obtained between DPPH inhibition and inhibition of both OH and peroxyl radicals. In addition, good correlations were obtained between DPPH inhibition and antioxidant activities in sunflower oil and liver homogenate systems. Conclusions In conclusion, the structures of good anti radical and antioxidant phenols and anilines are defined. The obtained good correlations imply that measuring anti DPPH activity can be used as a simple predictive test for the anti hydroxyl and peroxyl radical, and antioxidant activities. Kinetic measurements showed that strong antioxidants with high activity have also high reaction rates indicating that factors stabilizing the phenoxyl radicals lower also the activation energy of the hydrogen transfer process. PMID:23497653

The organ transplantation act and recent trends in Korea.

PubMed

Joo, Ho No

2013-03-01

The Organ Transplantation Act, including transplantation of organs from brain-dead donors, entered into force in Korea on February 9, 2000. This article introduces the Organ Transplantation Act, focusing on scope of the Act, determination of brain death, removal of organs from brain-dead or deceased donors, removal from living donors, organ allocation, and prohibition of trade in human organs. Especially, some primary ethical dilemmas surrounding organ allocation arise from the shortage of available organs. The primary ethical problems surrounding organ allocation are as follows. A key purpose of the organ donation incentive system is to increase the number of organ transplants from brain-dead donors. In particular, the priority for kidney patient was allowed in consideration of doctor's strong desire to increase the brain-dead donors. Also, the organ allocation criteria based on the organ donation incentive system appear unfair, especially for the kidney patient, because the criteria do not fit the principles of distributive justice. In the future, the organ donation incentive system itself may need to be reexamined.

Breast milk donors in France: a portrait of the typical donor and the utility of milk banking in the French breastfeeding context.

PubMed

Azema, Emilie; Callahan, Stacey

2003-05-01

Although information regarding attitudes and characteristics of human blood donors has been researched, little is known about the motivations and demographic and personality characteristics of women who choose to donate their breast milk. Eight milk banks in France participated in a study examining donor characteristics, providing data on 103 women. The results showed that the donors were women of average childbearing age with strong support at home. Almost half did not work outside of the home, compared to the national average of 80% of women in this age group; similarly, a large number (currently working or not) were from the health and social services fields. Reasons for donation were largely altruistic, and a general optimistic attitude prevailed within the participants. The results of this study provide useful information for the recruitment of potential donors as well as information on how to facilitate and provide optimal service through milk donation.

Nitroreductase-dependent mutagenicity of p-nitrophenylhydroxylamine and its N-acetyl and N-formyl hydroxamic acids.

PubMed

Corbett, M D; Wei, C; Corbett, B R

1985-05-01

p-Nitrophenylhydroxylamine (NPH) and two hydroxamic acids derived from it were synthesized and subjected to mutagenicity testing in Salmonella typhimurium strains TA98, TA98NR, TA1538 and TA1538NR. In addition, p-dinitrobenzene (DNB), p-nitroaniline (NA) and p-nitroacetanilide (AcNA) were simultaneously examined for mutagenic action against these four tester strains. NPH, its N-acetyl (AcNPH) and N-formyl (FoNPH) derivatives, and also DNB displayed strong mutagenic action to the nitroreductase-containing strains, TA98 and TA1538. NPH was the most potent chemical in this series against both of these strains, while the two hydroxamic acids AcNPH and FoNPH, and also DNB displayed approximately the same degree of mutagenicity. In the nitroreductase-deficient strains, TA98NR and TA1538NR, the mutagenicity of these four compounds was markedly reduced. The necessity for nitroreduction in order to activate these promutagens is fairly certain; however, the lack of mutagenicity of NA and AcNA towards all four tester strains made the interpretation of these data somewhat more complicated. Several possible bioactivation pathways were presented, with one mechanism in particular being proposed. This mechanism requires only that the strong electron-withdrawing nitro group be converted to an electron-donating group by bacterial nitroreductase. Such a mechanism is unique for the bioactivation of nitro aromatics by nitroreductase, since the enzymatic reduction need not produce the intermediary hydroxylamine metabolite.

Worthless donations: male deception and female counter play in a nuptial gift-giving spider

PubMed Central

2011-01-01

Background In nuptial gift-giving species, benefits of acquiring a mate may select for male deception by donation of worthless gifts. We investigated the effect of worthless gifts on mating success in the spider Pisaura mirabilis. Males usually offer an insect prey wrapped in silk; however, worthless gifts containing inedible items are reported. We tested male mating success in the following experimental groups: protein enriched fly gift (PG), regular fly gift (FG), worthless gift (WG), or no gift (NG). Results Males that offered worthless gifts acquired similar mating success as males offering nutritional gifts, while males with no gift experienced reduced mating success. The results suggest that strong selection on the nuptial gift-giving trait facilitates male deception by donation of worthless gifts. Females terminated matings faster when males offered worthless donations; this demonstrate a cost of deception for the males as shorter matings lead to reduced sperm transfer and thus give the deceiving males a disadvantage in sperm competition. Conclusion We propose that the gift wrapping trait allows males to exploit female foraging preference by disguising the gift content thus deceiving females into mating without acquiring direct benefits. Female preference for a genuine prey gift combined with control over mating duration, however, counteracts the male deception. PMID:22082300

Worthless donations: male deception and female counter play in a nuptial gift-giving spider.

PubMed

Albo, Maria J; Winther, Gudrun; Tuni, Cristina; Toft, Søren; Bilde, Trine

2011-11-14

In nuptial gift-giving species, benefits of acquiring a mate may select for male deception by donation of worthless gifts. We investigated the effect of worthless gifts on mating success in the spider Pisaura mirabilis. Males usually offer an insect prey wrapped in silk; however, worthless gifts containing inedible items are reported. We tested male mating success in the following experimental groups: protein enriched fly gift (PG), regular fly gift (FG), worthless gift (WG), or no gift (NG). Males that offered worthless gifts acquired similar mating success as males offering nutritional gifts, while males with no gift experienced reduced mating success. The results suggest that strong selection on the nuptial gift-giving trait facilitates male deception by donation of worthless gifts. Females terminated matings faster when males offered worthless donations; this demonstrate a cost of deception for the males as shorter matings lead to reduced sperm transfer and thus give the deceiving males a disadvantage in sperm competition. We propose that the gift wrapping trait allows males to exploit female foraging preference by disguising the gift content thus deceiving females into mating without acquiring direct benefits. Female preference for a genuine prey gift combined with control over mating duration, however, counteracts the male deception.

Energy level alignment and quantum conductance of functionalized metal-molecule junctions: Density functional theory versus GW calculations

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

Jin, Chengjun; Markussen, Troels; Thygesen, Kristian S., E-mail: thygesen@fysik.dtu.dk

We study the effect of functional groups (CH{sub 3}*4, OCH{sub 3}, CH{sub 3}, Cl, CN, F*4) on the electronic transport properties of 1,4-benzenediamine molecular junctions using the non-equilibrium Green function method. Exchange and correlation effects are included at various levels of theory, namely density functional theory (DFT), energy level-corrected DFT (DFT+Σ), Hartree-Fock and the many-body GW approximation. All methods reproduce the expected trends for the energy of the frontier orbitals according to the electron donating or withdrawing character of the substituent group. However, only the GW method predicts the correct ordering of the conductance amongst the molecules. The absolute GWmore » (DFT) conductance is within a factor of two (three) of the experimental values. Correcting the DFT orbital energies by a simple physically motivated scissors operator, Σ, can bring the DFT conductances close to experiments, but does not improve on the relative ordering. We ascribe this to a too strong pinning of the molecular energy levels to the metal Fermi level by DFT which suppresses the variation in orbital energy with functional group.« less

Photoinduced electron transfer interaction of anthraquinones with aniline quenchers: Influence of methyl substitution in aniline donors

NASA Astrophysics Data System (ADS)

Sivakumar, V.; Ponnamma, Deepalekshmi; Hussein, Yasser H. A.

2017-02-01

Photoinduced electron transfer between triplet state of 9,10-anthraquinone (AQ) and its two derivatives: 2-chloro-9,10-anthraquinone (CAQ) and sodium anthraquinone-2-sulfonate (AQS) and ground state aniline (AN) and its dimethyl substitutions: 2,3-dimethylaniline (2,3-DMA), 2,6-dimethylaniline (2,6-DMA), 3,5-dimethylaniline (3,5-DMA) and N,N-dimethylaniline (N,N-DMA) is studied using nanosecond laser flash photolysis at room temperature. Detection of radical bands of quinone anions and aniline cations along with their formation and/or decay kinetics are used to confirm the electron transfer (ET) process. In MeCN medium, AN quenches the triplet state of CAQ (CAQT) but not the triplets AQT or AQST. However in aqueous medium, AN quenches AQST and forms radical ion pair. All the DMAs can react through ET with all the triplet quinones at different degrees of efficiency in MeCN medium. Noticeably, the ring substituted DMAs are less efficient in electron donation to AQT or AQST while the N,N-DMA shows high efficiency in donating electron to all triplet quinones in MeCN medium. Charge distribution of donor molecules, in MeCN medium is calculated using density functional theory (DFT), and shows an enhancement of electron density of the ring of N,N-DMA, making it an ideal electron donor for ET studies compared to other DMAs. This systematic selection and usage of anilines with electrochemically tunable quinones can be viewed as a working model of donor-acceptor system that can be utilized in photoinduced ET applications.

Latex-mediated synthesis of ZnS nanoparticles: green synthesis approach

NASA Astrophysics Data System (ADS)

Hudlikar, Manish; Joglekar, Shreeram; Dhaygude, Mayur; Kodam, Kisan

2012-05-01

A low-cost, green synthesis of ZnS nanoparticles is reported using 0.3 % latex solution prepared from Jatropha curcas L. ZnS nanoparticles were characterized by X-ray diffraction, selected area electron diffraction, transmission electron microscopy, energy dispersive analysis of X-rays, UV-vis optical absorption and photoluminescence techniques. Fourier Transform Infrared Spectroscopy was performed to find the role of cyclic peptides namely curcacycline A (an octapeptide), curcacycline B (a nonapeptide) and curcain (an enzyme) as a possible reducing and stabilizing agents present in the latex of J. curcas L. The average size of ZnS nanoparticles was found to be 10 nm. Latex of J. curcas L. itself acts as a source of sulphide (S-2) ions that are donated to Zn ions under present experimental conditions. Source of sulphide (S-2) ions is still unclear, but we speculate that cysteine or thiol residues present in enzyme curcain may be donating these sulphide (S-2) ions.

Thiaflavan scavenges radicals and inhibits DNA oxidation: a story from the ferrocene modification.

PubMed

Lai, Hai-Wang; Liu, Zai-Qun

2014-06-23

4-Thiaflavan is a sulfur-substituted flavonoid with a benzoxathiin scaffold. The aim of this work is to compare abilities of sulfur and oxygen atom, hydroxyl groups, and ferrocene moiety at different positions of 4-thiaflavan to trap radicals and to inhibit DNA oxidation. It is found that abilities of thiaflavans to trap radicals and to inhibit DNA oxidation are increased in the presence of ferrocene moiety and are further improved by the electron-donating group attaching to thiaflavan skeleton. It can be concluded that the ferrocene moiety plays the major role for thiaflavans to be antioxidants even in the absence of phenolic hydroxyl groups. On the other hand, the antioxidant effectiveness of phenolic hydroxyl groups in thiaflavans can be improved by the electron-donating group. The influences of sulfur and oxygen atoms in thiaflavans on the antioxidant property of para-hydroxyl group exhibit different manners when the thiaflavans are used to trap radicals and to inhibit DNA oxidation. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Conductivity Modifications of Graphene by Electron Donative Organic Molecules

NASA Astrophysics Data System (ADS)

Masujima, Hiroaki; Mori, Takehiko; Hayamizu, Yuhei

2017-07-01

Graphene has been studied for the application of transparent electrodes in flexible electrical devices with semiconductor organics. Control of the charge carrier density in graphene is crucial to reduce the contact resistance between graphene and the active layer of organic semiconductor. Chemical doping of graphene is an approach to change the carrier density, where the adsorbed organic molecules donate or accept electrons form graphene. While various acceptor organic molecules have been demonstrated so far, investigation about donor molecules is still poor. In this work, we have investigated doping effect in graphene field-effect transistors functionalized by organic donor molecules such as dibenzotetrathiafulvalene (DBTTF), hexamethyltetrathiafulvalene (HMTTF), 1,5-diaminonaphthalene (DAN), and N, N, N', N'-tetramethyl- p-phenylenediamine (TMPD). Based on conductivity measurements of graphene transistors, the former three molecules do not have any significant effect to graphene transistors. However, TMPD shows effective n-type doping. The doping effect has a correlation with the level of highest occupied molecular orbital (HOMO) of each molecule, where TMPD has the highest HOMO level.

Novel High Efficient Organic Photovoltaic Materials: Final Summary of Research

NASA Technical Reports Server (NTRS)

Sun, Sam

2002-01-01

The objectives and goals of this project were to investigate and develop high efficient, lightweight, and cost effective materials for potential photovoltaic applications, such as solar energy conversion or photo detector devices. Specifically, as described in the original project proposal, the target material to be developed was a block copolymer system containing an electron donating (or p-type) conjugated polymer block coupled to an electron withdrawing (or n-type) conjugated polymer block through a non-conjugated bridge unit. Due to several special requirements of the targeted block copolymer systems, such as electron donating and withdrawing substituents, conjugated block structures, processing requirement, stability requirement, size controllability, phase separation and self ordering requirement, etc., many traditional or commonly used block copolymer synthetic schemes are not suitable for this system. Therefore, the investigation and development of applicable and effective synthetic protocols became the most critical and challenging part of this project. During the entire project period, and despite the lack of a proposed synthetic polymer postdoctoral research associate due to severe shortage of qualified personnel in the field, several important accomplishments were achieved in this project and are briefly listed and elaborated. A more detailed research and experimental data is listed in the Appendix.

Infrared Detector Research

DTIC Science & Technology

1976-08-01

Bratt, Howard Davis, Frank Renda , Paul Chia, Arthur Lockwood. Bell Telephone Labs Leo F. Johnson, Alfred U. MacRae, Paul Norton. Texas Ins truments Werner...impurities which can "donate" their extra electron not required for bonding with the silicon atoms. When there are more acceptors than donors the material...will be p-type. The extra electrons from the donors can complete the bond missing due to the boron atoms. This process is call compensation. The

An electronic rationale for observed initiation rates in ruthenium-mediated olefin metathesis: charge donation in phosphine and N-heterocyclic carbene ligands.

PubMed

Getty, Kendra; Delgado-Jaime, Mario Ulises; Kennepohl, Pierre

2007-12-26

Ru K-edge XAS data indicate that second generation ruthenium-based olefin metathesis precatalysts (L = N-heterocyclic carbene) possess a more electron-deficient metal center than in the corresponding first generation species (L = tricyclohexylphosphine). This surprising effect is also observed from DFT calculations and provides a simple rationale for the slow phosphine dissociation kinetics previously noted for second-generation metathesis precatalysts.

A quantum informational approach for dissecting chemical reactions

NASA Astrophysics Data System (ADS)

Duperrouzel, Corinne; Tecmer, Paweł; Boguslawski, Katharina; Barcza, Gergely; Legeza, Örs; Ayers, Paul W.

2015-02-01

We present a conceptionally different approach to dissect bond-formation processes in metal-driven catalysis using concepts from quantum information theory. Our method uses the entanglement and correlation among molecular orbitals to analyze changes in electronic structure that accompany chemical processes. As a proof-of-principle example, the evolution of nickel-ethene bond-formation is dissected, which allows us to monitor the interplay of back-bonding and π-donation along the reaction coordinate. Furthermore, the reaction pathway of nickel-ethene complexation is analyzed using quantum chemistry methods, revealing the presence of a transition state. Our study supports the crucial role of metal-to-ligand back-donation in the bond-forming process of nickel-ethene.

No-carrier-added (NCA) aryl ([sup 18]F) fluorides via the nucleophilic aromatic substitution of electron rich aromatic rings

DOEpatents

Yushin Ding; Fowler, J.S.; Wolf, A.P.

1993-10-19

A method for synthesizing no-carrier-added (NCA) aryl [.sup.18 F] fluoride substituted aromatic aldehyde compositions bearing an electron donating group is described. The method of the present invention includes the step of reacting aromatic nitro aldehydes having a suitably protected hydroxyl substitutent on an electron rich ring. The reaction is The U.S. Government has rights in this invention pursuant to Contract Number DE-AC02-76CH00016, between the U.S. Department of Energy and Associated Universities Inc.

No-carrier-added (NCA) aryl (18E) fluorides via the nucleophilic aromatic substitution of electron rich aromatic rings

DOEpatents

Ding, Yu-Shin; Fowler, Joanna S.; Wolf, Alfred P.

1993-01-01

A method for synthesizing no-carrier-added (NCA) aryl [.sup.18 F] fluoride substituted aromatic aldehyde compositions bearing an electron donating group is described. The method of the present invention includes the step of reacting aromatic nitro aldehydes having a suitably protected hydroxyl substitutent on an electron rich ring. The reaction is The U.S. Government has rights in this invention pursuant to Contract Number DE-AC02-76CH00016, between the U.S. Department of Energy and Associated Universities Inc.

Should health care professionals encourage living kidney donation?

PubMed

Hilhorst, Medard T; Kranenburg, Leonieke W; Busschbach, Jan J V

2007-03-01

Living kidney donation provides a promising opportunity in situations where the scarcity of cadaveric kidneys is widely acknowledged. While many patients and their relatives are willing to accept its benefits, others are concerned about living kidney programs; they appear to feel pressured into accepting living kidney transplantations as the only proper option for them. As we studied the attitudes and views of patients and their relatives, we considered just how actively health care professionals should encourage living donation. We argue that active interference in peoples' personal lives is justified - if not obligatory. First, we address the ambiguous ideals of non-directivity and value neutrality in counselling. We describe the main pitfalls implied in these concepts, and conclude that these concepts cannot account for the complex reality of living donation and transplantation. We depict what is required instead as truthful information and context-relative counselling. We then consider professional interference into personal belief systems. We argue that individual convictions are not necessarily strong, stable, or deep. They may be flawed in many ways. In order to justify interference in peoples' personal lives, it is crucial to understand the structure of these convictions. Evidence suggests that both patients and their relatives have attitudes towards living kidney donation that are often open to change and, accordingly, can be influenced. We show how ethical theories can account for this reality and can help us to discern between justified and unjustified interference. We refer to Stephen Toulmin's model of the structure of logical argument, the Rawlsian model of reflective equilibrium, and Thomas Nagel's representation of the particularistic position.

Organometallic benzylidene anilines: donor-acceptor features in NCN-pincer Pt(ii) complexes with a 4-(E)-[(4-R-phenyl)imino]methyl substituent.

PubMed

Batema, Guido D; Lutz, Martin; Spek, Anthony L; van Walree, Cornelis A; van Klink, Gerard P M; van Koten, Gerard

2014-08-28

A series of organometallic 4,4'-substituted benzylidene aniline complexes 4-ClPt-3,5-(CH2NMe2)2C6H2CH[double bond, length as m-dash]NC6H4R'-4', abbreviated as PtCl[NCN(CH[double bond, length as m-dash]NC6H4R'-4')-4], with R' = NMe2, Me, H, Cl, CN (, respectively), was synthesized via a Schiff-base condensation reaction involving reaction of PtCl[NCN(CH[double bond, length as m-dash]O)-4] () with the appropriate 4-R'-substituted aniline derivative () in toluene. The resulting arylplatinum(ii) products were obtained in 75-88% yield. Notably, product was also obtained in 68% yield from a reaction in the solid state by grinding solid with aniline . The structures of , , and in the solid state (single crystal X-ray diffraction) showed a non-planar geometry, in particular for compound . The electronic interaction between the donor benzylidene fragment PtCl(NCN-CH) and the para-R' aniline substituent through the azomethine bridge was studied with NMR and UV/Vis spectroscopy. Linear correlations were found between the azomethine (1)H, the (195)Pt NMR and various (13)C NMR chemical shifts, and the substituent parameters σF and σR of R' at the aniline site. In common with organic benzylidene anilines, the azomethine (1)H NMR chemical shift showed anomalous substituent behavior. The (195)Pt NMR chemical shift of the platinum center can be used as a probe for the electronic properties of the delocalized π-system of the benzylidene aniline framework, to which it is connected. The dual substituent parameter treatment of the azomethine (13)C NMR shift gave important insight into the unique behaviour of the Pt-pincer group as a substituent. Inductively, it is a very strong electron-withdrawing group, whereas mesomerically it behaves like a very strong electron donating group.

Novel High Efficient Organic Photovoltaic Materials: Appendix for Summary of Research. Appendix

NASA Technical Reports Server (NTRS)

Sun, Sam

2002-01-01

There are many different kinds of conjugated polymers that may be useful in photovoltaic devices. So far, the most popular and successful conjugated polymers used in photovoltaic devices include poly(1,4-)phenylenevinylenes (PPV), C60 and their derivatives. The discovery of electro-luminescence in PPV has stimulated a great deal of interest in developing "plastic" solid-state semiconductor devices. The overall synthetic methodology for the preparation of PPV can be divided into three main categories: (1) side chain derivatization, (2) precursor approach, and (3) in-situ polymerization. In this project, the first method was adopted. As discussed in project proposal and literatures, the overall efficiency of photovoltaic devices containing conjugated polymers is determined by the materials ability to generate excitons from incoming radiation, and then to separate the charges at donor/acceptor interfaces, and then to transport charges to respective electrodes. Given that effective exciton diffusion range are typical less then 30 nm, unique morphological structures are needed. This need led to several research groups to the idea that interpenetrating or bi-continuous networks of donor (electron donating) and acceptor (electron withdrawing) polymers should give better results. One approach involved the use of functionalized PPV. The attachment of electron withdrawing cyano groups to a PPV forms the CN-PPV, making it a strong electron acceptor. Underivatized PPV is a generally considered a hole-transporting material. Using blends of MEH-PPV, a soluble donor PPV derivative, as a hole transporter and CN-PPV as an electron transporter, a quantum efficiencies of up to 6% was achieved.

US organ donation breakthrough collaborative increases organ donation.

PubMed

Shafer, Teresa J; Wagner, Dennis; Chessare, John; Schall, Marie W; McBride, Virginia; Zampiello, Francis A; Perdue, Jade; O'Connor, Kevin; Lin, Monica J-Y; Burdick, James

2008-01-01

More than 92000 Americans are on waiting lists for organ transplants, and an average of 17 of them die each day while waiting. The US Organ Donation Breakthrough Collaborative (ODBC), which began in 2003 at the request of the Secretary of the US Department of Health and Human Services, was a formal, concerted effort of the donation and transplantation community to bring about a major change to improve the organ donation system. The nationwide Collaborative was housed within a Health and Human Services agency, the Health Resources and Services Administration (HRSA) Division of Transplantation, and included participation of the organ procurement organizations (OPOs) throughout the United States and the American hospitals with the largest organ-donor potential. HRSA leaders used the Breakthrough Series Collaborative method, originally developed by the Institute for Healthcare Improvement, as the model for the intervention. Expert practitioners drawn from hospitals and OPOs that had already demonstrated their ability to achieve and sustain high organ donation rates were chosen as faculty for the collaborative and best practices were gleaned from their institutions. The number of organ donors in Collaborative hospitals increased 14.1% in the first year, a 70% greater increase than the 8.3% increase experienced by non-Collaborative hospitals. Moreover, the increased organ recovery continued into the post-Collaborative periods. Between October 2003 and September 2006, the number of total US organ donors increased 22.5%, an increase 4-fold greater than the 5.5% increase measured over the same number of years in the immediate pre-Collaborative period. The study did not involve a randomized design, but time-series analysis using statistical process control charts shows a highly significant discontinuity in the rate of increase in participating hospitals concurrent with the Collaborative program, and strongly suggests that the activities of the Collaborative were a major contributor to this increase. Given the stable nature of the historical increases over many years, the HRSA estimates that more than 4000 annual additional transplants have occurred in association and apparently as a result of these increases in organ donation.

Donation after cardiocirculatory death in Canada

PubMed Central

Shemie, Sam D.; Baker, Andrew J.; Knoll, Greg; Wall, William; Rocker, Graeme; Howes, Daniel; Davidson, Janet; Pagliarello, Joe; Chambers-Evans, Jane; Cockfield, Sandra; Farrell, Catherine; Glannon, Walter; Gourlay, William; Grant, David; Langevin, Stéphan; Wheelock, Brian; Young, Kimberly; Dossetor, John

2006-01-01

These recommendations are the result of a national, multidisciplinary, year-long process to discuss whether and how to proceed with organ donation after cardiocirculatory death (DCD) in Canada. A national forum was held in February 2005 to discuss and develop recommendations on the principles, procedures and practice related to DCD, including ethical and legal considerations. At the forum's conclusion, a strong majority of participants supported proceeding with DCD programs in Canada. The forum also recognized the need to formulate and emphasize core values to guide the development of programs and protocols based on the medical, ethical and legal framework established at this meeting. Although end-of-life care should routinely include the opportunity to donate organs and tissues, the duty of care toward dying patients and their families remains the dominant priority of health care teams. The complexity and profound implications of death are recognized and should be respected, along with differing personal, ethnocultural and religious perspectives on death and donation. Decisions around withdrawal of life-sustaining therapies, management of the dying process and the determination of death by cardiocirculatory criteria should be separate from and independent of donation and transplant processes. The recommendations in this report are intended to guide individual programs, regional health authorities and jurisdictions in the development of DCD protocols. Programs will develop based on local leadership and advance planning that includes education and engagement of stakeholders, mechanisms to assure safety and quality and public information. We recommend that programs begin with controlled DCD within the intensive care unit where (after a consensual decision to withdraw life-sustaining therapy) death is anticipated, but has not yet occurred, and unhurried consent discussions can be held. Uncontrolled donation (where death has occurred after unanticipated cardiac arrest) should only be considered after a controlled DCD program is well established. Although we recommend that programs commence with kidney donation, regional transplant expertise may guide the inclusion of other organs. The impact of DCD, including pre-and post-mortem interventions, on donor family experiences, organ availability, graft function and recipient survival should be carefully documented and studied. PMID:17124739

[Sb{sub 4}Au{sub 4}Sb{sub 4}]{sup 2−}: A designer all-metal aromatic sandwich

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

Tian, Wen-Juan; You, Xue-Rui; Guo, Jin-Chang

We report on the computational design of an all-metal aromatic sandwich, [Sb{sub 4}Au{sub 4}Sb{sub 4}]{sup 2−}. The triple-layered, square-prismatic sandwich complex is the global minimum of the system from Coalescence Kick and Minima Hopping structural searches. Following a standard, qualitative chemical bonding analysis via canonical molecular orbitals, the sandwich complex can be formally described as [Sb{sub 4}]{sup +}[Au{sub 4}]{sup 4−}[Sb{sub 4}]{sup +}, showing ionic bonding characters with electron transfers in between the Sb{sub 4}/Au{sub 4}/Sb{sub 4} layers. For an in-depth understanding of the system, one needs to go beyond the above picture. Significant Sb → Au donation and Sb ←more » Au back-donation occur, redistributing electrons from the Sb{sub 4}/Au{sub 4}/Sb{sub 4} layers to the interlayer Sb–Au–Sb edges, which effectively lead to four Sb–Au–Sb three-center two-electron bonds. The complex is a system with 30 valence electrons, excluding the Sb 5s and Au 5d lone-pairs. The two [Sb{sub 4}]{sup +} ligands constitute an unusual three-fold (π and σ) aromatic system with all 22 electrons being delocalized. An energy gap of ∼1.6 eV is predicted for this all-metal sandwich. The complex is a rare example for rational design of cluster compounds and invites forth-coming synthetic efforts.« less

Design of aromatic-containing cell-penetrating peptide mimics with structurally modified π electronics.

PubMed

deRonde, Brittany M; Birke, Alexander; Tew, Gregory N

2015-02-09

Cell-penetrating peptides (CPPs) and their synthetic mimics (CPPMs) represent a class of molecules that facilitate the intracellular delivery of various cargo. Previous studies indicated that the presence of aromatic functionalities improved CPPM activity. Given that aromatic functionalities play prominent roles in membrane biology and participate in various π interactions, we explored whether these interactions could be optimized for improved CPPM activity. CPPMs were synthesized by ring-opening metathesis polymerization by using monomers that contained aromatic rings substituted with electron-donating and electron-withdrawing groups and covered an electrostatic potential range from -29.69 to +15.57 kcal mol(-1) . These groups altered the quadrupole moments of the aromatic systems and were used to test if such structural modifications changed CPPM activity. CPPMs were added to dye-loaded vesicles and the release of carboxyfluorescein was monitored as a function of polymer concentration. Changes in the effective polymer concentration to release 50% of the dye (effective concentration, EC50 ) were monitored. Results from this assay showed that the strength of the electron-donating and electron-withdrawing groups incorporated in the CPPMs did not alter polymer EC50 values or activity. This suggests that other design parameters may have a stronger impact on CPPM activity. In addition, these results indicate that a wide range of aromatic groups can be incorporated without negatively impacting polymer activity. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The two faces of hydrogen-bond strength on triple AAA-DDD arrays.

PubMed

Lopez, Alfredo Henrique Duarte; Caramori, Giovanni Finoto; Coimbra, Daniel Fernando; Parreira, Renato Luis Tame; da Silva, Éder Henrique

2013-12-02

Systems that are connected through multiple hydrogen bonds are the cornerstone of molecular recognition processes in biology, and they are increasingly being employed in supramolecular chemistry, specifically in molecular self-assembly processes. For this reason, the effects of different substituents (NO2, CN, F, Cl, Br, OCH3 and NH2) on the electronic structure, and consequently on the magnitude of hydrogen bonds in triple AAA-DDD arrays (A=acceptor, D=donor) were evaluated in the light of topological [electron localization function (ELF) and quantum theory of atoms in molecules (QTAIM)], energetic [Su-Li energy-decomposition analysis (EDA) and natural bond orbital analysis (NBO)], and geometrical analysis. The results based on local H-bond descriptors (geometries, QTAIM, ELF, and NBO) indicate that substitutions with electron-withdrawing groups on the AAA module tend to strengthen, whereas electron-donating substituents tend to weaken the covalent character of the AAA-DDD intermolecular H-bonds, and also indicate that the magnitude of the effect is dependent on the position of substitution. In contrast, Su-Li EDA results show an opposite behavior when compared to local H-bond descriptors, indicating that electron-donating substituents tend to increase the magnitude of H-bonds in AAA-DDD arrays, and thus suggesting that the use of local H-bond descriptors describes the nature of H bonds only partially, not providing enough insight about the strength of such H bonds. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Knowledge, Attitudes and Proposals of Medical Students Concerning Transplantations in Greece

PubMed Central

Dardavessis, Theodore; Xenophontos, Pantelis; Haidich, Anna-Bettina; Kiritsi, Maria; Vayionas, Malamatenia Arvanitidou

2011-01-01

Objectives: In Greece, there is limited research on issues related to organ donation. We aimed to study the attitudes, knowledge, and actions of local medical students regard to organ donation and transplantations of tissues and organs in Greece. Methods: This cross-sectional questionnaire based survey was done in Laboratory of Hygiene and Social Medicine, School of Medicine, Aristotle University of Thessaloniki, Greece on medical students in years 1 to 6. In a sample of 600 medical students, a special anonymous questionnaire, which included data as sex, age, and semester of studies, as well as questions regarding certain aspects of transplantation, was distributed. 558 valid questionnaires were completed (men 52.3% and women 47.7%). Results: The vast majority of the sample (93.6%) were in favor of transplantations whereas 32 (5.7%) of the students claimed to be organ donors. 78.9% claimed ignorance of the existing legislation concerning transplantations and organ donation in our country. 81.2% believed that the voting of law, which would consider all Greek organ donors after death will cause strong reactions. As the main causes, responsible for the shortage of transplants in our country were stated to be the inadequate public information, Greek mentality, and the lack of organized transplant centers. Public information through Media, a lifelong free health check-up for organ donors and activation of voluntary organizations that promote organ donation were proposed as the most important actions that could increase organ donation and transplantations in Greece. Conclusions: The need for further informative actions stressing the importance of organ donations appears to be the only way to increase transplantations in our country and towards this direction medical students could also be activated. A new medical curriculum should increase medical students′ awareness of the organ shortage problem. Public education is recommended to correct misconceptions. PMID:21811659

Socioeconomic factors as predictors of organ donation.

PubMed

Shah, Malay B; Vilchez, Valery; Goble, Adam; Daily, Michael F; Berger, Jonathan C; Gedaly, Roberto; DuBay, Derek A

2018-01-01

Despite numerous initiatives to increase solid organs for transplant, the gap between donors and recipients widens. There is little in the literature identifying socioeconomic predictors for donation. We evaluate the correlation between socioeconomic factors and familial authorization for donation. A retrospective analysis of adult potential donor referrals between 2007 and 2012 to our organ procurement organization (OPO) was performed. Potential donor information was obtained from the OPO database, death certificates, and the US Census Report. Data on demographics, education, residence, income, registry status, cause and manner of death, as well as OPO assessments and approach for donation were collected. End point was familial authorization for donation. A total of 1059 potential donors were included, with an overall authorization rate of 47%. The majority was not on the donor registry (73%). Younger donors (18-39 y: odds ratio [OR] = 4.9, P < 0.001; 40-60 y: OR = 2.1, P < 0.001), higher levels of education (college: OR = 2.5, P = 0.005; graduate studies: OR = 3.9, P = 0.002), prior listing on the donor registry (OR = 10.3, P < 0.001), and residence in counties with lower poverty rates than the US rates (OR = 1.7, P = 0.02) were independently associated with higher authorization rates. Decoupling (OR = 3.1, P < 0.001) and donation first mentioned by the local health care provider (OR = 1.8, P = 0.01) were also independently associated with higher authorization rates. Donor registration correlated most strongly with the highest authorization rates. These results indicate that public educational efforts in populations with unfavorable socioeconomic considerations may be beneficial in improving donor registration. Collaborations with local providers as well as OPO in-hospital assessments and approach techniques can help with improving authorization rates. Copyright © 2017 Elsevier Inc. All rights reserved.

Mechanisms for the adsorption of substituted nitrobenzenes by smectite clays.

PubMed

Boyd, S A; Sheng, G; Teppen, B J; Johnston, C T

2001-11-01

To more fully understand the potential for transport of nitroaromatic compounds in soils and subsoils,the adsorption of a series of para- and meta-substituted nitrobenzenes (SNBs) by K-smectite clay was measured. Adsorption isotherms were fit to the Freundlich equation, and the resultant Freundlich adsorption coefficients (log(Kf) were positively correlated with the Hammett substituent constant (r2 = 0.80). This relationship and a positive reaction constant (p = 1.15) indicate that the adsorption reaction is favored by electron-withdrawing substituents. These results are consistent with an electron donor (smectite)-acceptor (substituted nitrobenzene) mechanism offered previously. However, quantum calculations did not reveal any systematic relationship between the Hammett constant and the electron density on the aromatic ring, which would explain a donor-acceptor relationship. Rather, electron density donated by a second substituent on nitrobenzene appears to be appropriated by the nitro group leaving ring electron density unchanged. Fourier transform infrared spectroscopy revealed shifts in the -NO2 vibrational modes of 1,3,5-trinitrobenzene (TNB) upon adsorption to K+-smectite that were consistent with the complexation of K+ by -NO2 groups. Such TNB vibrational shifts were not observed for SWy-1 saturated with more strongly hydrated cations (i.e., Na+, Mg2+, Ca2+, and Ba2+). The simultaneous interaction of multiple -NO2 groups with exchangeable K+ was indicated by molecular dynamic simulations. Adsorption of SNBs by smectite clays appears to result from the additive interactions of -NO2 groups and secondary substituents with interlayer K+ ions. Adsorption occurs to a greater or lesser extent depending on the abilities of substituents to complex additional interlayer cations and the water solubilities of SNBs. We conclude that the adsorption trends of SNBs on K-SAz-1 can be explained without recourse to hypothetical electron donor-acceptor complexes.

On the Brønsted acid-catalyzed homogeneous hydrolysis of furans.

PubMed

Nikbin, Nima; Caratzoulas, Stavros; Vlachos, Dionisios G

2013-11-01

Furan affairs: Electronic structure calculations of the homogeneous Brønsted acid-catalyzed hydrolysis of 2,5-dimethylfuran show that proton transfer to the β-position is rate-limiting and provides support that the hydrolysis follows general acid catalysis. By means of projected Fukui indices, we show this to be the case for unsubstituted, 2-, and 2,5-substituted furans with electron-donating groups. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

One-pot, two-step desymmetrization of symmetrical benzils catalyzed by the methylsulfinyl (dimsyl) anion.

PubMed

Ragno, Daniele; Bortolini, Olga; Giovannini, Pier Paolo; Massi, Alessandro; Pacifico, Salvatore; Zaghi, Anna

2014-08-14

An operationally simple one-pot, two-step procedure for the desymmetrization of benzils is herein described. This consists in the chemoselective cross-benzoin reaction of symmetrical benzils with aromatic aldehydes catalyzed by the methyl sulfinyl (dimsyl) anion, followed by microwave-assisted oxidation of the resulting benzoylated benzoins with nitrate, avoiding the costly isolation procedure. Both electron-withdrawing and electron-donating substituents may be accommodated on the aromatic rings of the final unsymmetrical benzil.

Reactivity measurement in estimation of benzoquinone and benzoquinone derivatives’ allergenicity

PubMed Central

Mbiya, Wilbes; Chipinda, Itai; Simoyi, Reuben H.; Siegel, Paul D.

2015-01-01

Benzoquinone (BQ) and benzoquinone derivatives (BQD) are used in the production of dyes and cosmetics. While BQ, an extreme skin sensitizer, is an electrophile known to covalently modify proteins via Michael Addition (MA) reaction whilst halogen substituted BQD undergo nucleophilic vinylic substitution (SNV) mechanism onto amine and thiol moieties on proteins, the allergenic effects of adding substituents on BQ have not been reported. The effects of inserting substituents on the BQ ring has not been studied in animal assays. However, mandated reduction/elimination of animals used in cosmetics testing in Europe has led to an increased need for alternatives for the prediction of skin sensitization potential. Electron withdrawing and electron donating substituents on BQ were assessed for effects on BQ reactivity toward nitrobenzene thiol (NBT). The NBT binding studies demonstrated that addition of EWG to BQ as exemplified by the chlorine substituted BQDs increased reactivity while addition of EDG as in the methyl substituted BQDs reduced reactivity. BQ and BQD skin allerginicity was evaluated in the murine local lymph node assay (LLNA). BQD with electron withdrawing groups had the highest chemical potency followed by unsubstituted BQ and the least potent were the BQD with electron donating groups. The BQD results demonstrate the impact of inductive effects on both BQ reactivity and allergenicity, and suggest the potential utility of chemical reactivity data for electrophilic allergen identification and potency ranking. PMID:26612505

Acceptor number-dependent ultrafast photo-physical properties of push-pull chromophores using time-resolved methods

NASA Astrophysics Data System (ADS)

Chi, Xiao-Chun; Wang, Ying-Hui; Gao, Yu; Sui, Ning; Zhang, Li-Quan; Wang, Wen-Yan; Lu, Ran; Ji, Wen-Yu; Yang, Yan-Qiang; Zhang, Han-Zhuang

2018-04-01

Three push-pull chromophores comprising a triphenylamine (TPA) as electron-donating moiety and functionalized β-diketones as electron acceptor units are studied by various spectroscopic techniques. The time-correlated single-photon counting data shows that increasing the number of electron acceptor units accelerates photoluminescence relaxation rate of compounds. Transient spectra data shows that intramolecular charge transfer (ICT) takes place from TPA units to β-diketones units after photo-excitation. Increasing the number of electron acceptor units would prolong the generation process of ICT state, and accelerate the excited molecule reorganization process and the relaxation process of ICT state.

The ultrastructural characteristics of porcine hepatocytes donated after cardiac death and preserved with warm machine perfusion preservation.

PubMed

Bochimoto, Hiroki; Matsuno, Naoto; Ishihara, Yo; Shonaka, Tatsuya; Koga, Daisuke; Hira, Yoshiki; Nishikawa, Yuji; Furukawa, Hiroyuki; Watanabe, Tsuyoshi

2017-01-01

The effects of warm machine perfusion preservation of liver grafts donated after cardiac death on the intracellular three-dimensional ultrastructure of the organelles in hepatocytes remain unclear. Here we analyzed comparatively the ultrastructure of the endomembrane systems in porcine hepatocytes under warm ischemia and successive hypothermic and midthermic machine perfusion preservation, a type of the warm machine perfusion. Porcine liver grafts which had a warm ischemia time of 60 minutes were perfused for 4 hours with modified University of Wisconsin gluconate solution. Group A grafts were preserved with hypothermic machine perfusion preservation at 8°C constantly for 4 hours. Group B grafts were preserved with rewarming up to 22°C by warm machine perfusion preservation for 4 hours. An analysis of hepatocytes after 60 minutes of warm ischemia by scanning electron microscope revealed the appearance of abnormal vacuoles and invagination of mitochondria. In the hepatocytes preserved by subsequent hypothermic machine perfusion preservation, strongly swollen mitochondria were observed. In contrast, the warm machine perfusion preservation could preserve the functional appearance of mitochondria in hepatocytes. Furthermore, abundant vacuoles and membranous structures sequestrating cellular organelles like autophagic vacuoles were frequently observed in hepatocytes after warm machine perfusion preservation. In conclusion, the ultrastructure of the endomembrane systems in the hepatocytes of liver grafts changed in accordance with the temperature conditions of machine perfusion preservation. In addition, temperature condition of the machine perfusion preservation may also affect the condition of the hepatic graft attributed to autophagy systems, and consequently alleviate the damage of the hepatocytes.

Photoinduced electron transfer interaction of anthraquinones with aniline quenchers: Influence of methyl substitution in aniline donors.

PubMed

Sivakumar, V; Ponnamma, Deepalekshmi; Hussein, Yasser H A

2017-02-15

Photoinduced electron transfer between triplet state of 9,10-anthraquinone (AQ) and its two derivatives: 2-chloro-9,10-anthraquinone (CAQ) and sodium anthraquinone-2-sulfonate (AQS) and ground state aniline (AN) and its dimethyl substitutions: 2,3-dimethylaniline (2,3-DMA), 2,6-dimethylaniline (2,6-DMA), 3,5-dimethylaniline (3,5-DMA) and N,N-dimethylaniline (N,N-DMA) is studied using nanosecond laser flash photolysis at room temperature. Detection of radical bands of quinone anions and aniline cations along with their formation and/or decay kinetics are used to confirm the electron transfer (ET) process. In MeCN medium, AN quenches the triplet state of CAQ (CAQ T ) but not the triplets AQ T or AQS T . However in aqueous medium, AN quenches AQS T and forms radical ion pair. All the DMAs can react through ET with all the triplet quinones at different degrees of efficiency in MeCN medium. Noticeably, the ring substituted DMAs are less efficient in electron donation to AQ T or AQS T while the N,N-DMA shows high efficiency in donating electron to all triplet quinones in MeCN medium. Charge distribution of donor molecules, in MeCN medium is calculated using density functional theory (DFT), and shows an enhancement of electron density of the ring of N,N-DMA, making it an ideal electron donor for ET studies compared to other DMAs. This systematic selection and usage of anilines with electrochemically tunable quinones can be viewed as a working model of donor-acceptor system that can be utilized in photoinduced ET applications. Copyright © 2016 Elsevier B.V. All rights reserved.

What will the crowd fund? Preferences of prospective donors for drug development fundraising campaigns.

PubMed

Dragojlovic, Nick; Lynd, Larry D

2016-12-01

Biomedical researchers are increasingly turning to project-based online fundraising (i.e., crowdfunding) as a complementary source of research funding. To help inform the fundraising strategies adopted by researchers who take this approach, we conducted an online survey of prospective donors in North America. Respondents indicated not only an overwhelming preference for donating to projects conducted by nonprofit research organizations, but also an openness to donating to companies that have a 'for-benefit' corporate structure. They also showed a strong preference for projects that have alternate sources of funding, that have the potential to yield a curative therapy, and that focus on common and pediatric diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

The expectations and attitudes of patients with chronic kidney disease toward living kidney donor transplantation: a thematic synthesis of qualitative studies.

PubMed

Hanson, Camilla S; Chadban, Steve J; Chapman, Jeremy R; Craig, Jonathan C; Wong, Germaine; Ralph, Angelique F; Tong, Allison

2015-03-01

Living kidney donation offers superior outcomes over deceased organ donation, but incurs psychosocial and ethical challenges for recipients because of the risks imposed on their donor. We aimed to describe the beliefs, attitudes, and expectations of patients with chronic kidney disease toward receiving a living kidney donor transplant. We conducted a systematic review of qualitative studies of patients' attitudes toward living kidney donation using a comprehensive literature search of electronic databases to February 2013. The findings were analyzed using thematic synthesis. Thirty-nine studies (n ≥ 1791 participants) were included. We identified six themes: prioritizing own health (better graft survival, accepting risk, and desperate aversion to dialysis), guilt and responsibility (jeopardizing donor health, anticipating donor regret, and causing donor inconvenience), ambivalence and uncertainty (doubting transplant urgency, insufficient information, confronted by unfamiliarity, and prognostic uncertainty), seeking decisional validation (a familial obligation, alleviating family burden, reciprocal benefits for donors, respecting donor autonomy, external reassurance, and religious approval), needing social support (avoiding family conflict, unrelenting indebtedness, and emotional isolation), and cautious donor recruitment (self-advocacy, lacking self-confidence, avoiding donor coercion, emotional vulnerability, respecting cultural, and religious taboos). Enhanced education and psychosocial support may help clarify, validate, and address patients' concerns regarding donor outcomes, guilt, relationship tensions, and donor recruitment. This may encourage informed decision-making, increase access to living kidney donation, and improve psychosocial adjustment for transplant recipients.

The blood donor identity survey: a multidimensional measure of blood donor motivations.

PubMed

France, Christopher R; Kowalsky, Jennifer M; France, Janis L; Himawan, Lina K; Kessler, Debra A; Shaz, Beth H

2014-08-01

Evidence indicates that donor identity is an important predictor of donation behavior; however, prior studies have relied on diverse, unidimensional measures with limited psychometric support. The goals of this study were to examine the application of self-determination theory to blood donor motivations and to develop and validate a related multidimensional measure of donor identity. Items were developed and administered electronically to a sample of New York Blood Center (NYBC) donors (n=582) and then to a sample of Ohio University students (n=1005). Following initial confirmatory factor analysis (CFA) on the NYBC sample to identify key items related to self-determination theory's six motivational factors, a revised survey was administered to the university sample to reexamine model fit and to assess survey reliability and validity. Consistent with self-determination theory, for both samples CFAs indicated that the best fit to the data was provided by a six-motivational-factor model, including amotivation, external regulation, introjected regulation, identified regulation, integrated regulation, and intrinsic regulation. The Blood Donor Identity Survey provides a psychometrically sound, multidimensional measure of donor motivations (ranging from unmotivated to donate to increasing levels of autonomous motivation to donate) that is suitable for nondonors as well as donors with varying levels of experience. Future research is needed to examine longitudinal changes in donor identity and its relationship to actual donation behavior. © 2014 AABB.

Is Decedent Race an Independent Predictor of Organ Donor Consent, or Merely a Surrogate Marker of Socioeconomic Status?

PubMed Central

DuBay, Derek A.; Redden, David; Haque, Akhlaque; Gray, Stephen; Fouad, Mona; Siminoff, Laura A.; Holt, Cheryl; Kohler, Connie; Eckhoff, Devin

2013-01-01

Background Studies have demonstrated that African American race is a strong predictor of non-donation. However, it is often and correctly argued that African American race is a crude explanatory variable that is a surrogate marker of socioeconomic status (SES), education and access to health care. We hypothesized that when controlling for these factors, African American race would cease to be a predictor of organ donation. Methods A retrospective review was performed of 1292 Alabama decedents approached for organ donation between 2006 and 2009. Multivariable logistic regression models were constructed to identify the most parsimonious model that could explain the variation in the log-odds of obtaining consent. Results Consent for donation was obtained from 49% of the decedent's families. Household income was a predictor of organ donor consent only in Caucasians. Surprisingly, household income was not statistically different between consented and non-consented African American decedents ($25,147 vs. $26,137; p=0.90). On multivariable analysis, education, urban residence and shorter distance between the decedent residence and donor hospital were significantly associated with obtaining consent for organ donation. On univariate analysis, the odds of donor consent in Caucasians compared to African Americans was 2.76 (95% CI 2.17 – 3.57). When controlling for SES and access to healthcare variables, the odds of donor consent increased to 4.36 (95% CI 2.88 – 6.61). Conclusions We interpret this result to indicate that there remains unknown but important factor(s) associated with both race and obtaining organ donor consent. Further studies are required to isolate and determine whether this factor(s) is modifiable. PMID:23018878

Water-soluble cationic conjugated polymers: response to electron-rich bioanalytes.

PubMed

Rochat, Sébastien; Swager, Timothy M

2013-11-27

We report the concise synthesis of a symmetrical monomer that provides a head-to-head pyridine building block for the preparation of cationic conjugated polymers. The obtained poly(pyridinium-phenylene) polymers display appealing properties such as high electron affinity, charge-transport upon n-doping, and optical response to electron-donating analytes. A simple assay for the optical detection of low micromolar amounts of a variety of analytes in aqueous solution was developed. In particular, caffeine could be measured at a 25 μM detection limit. The reported polymers are also suitable for layer-by-layer film formation.

An Electron-Transporting Thiazole-Based Polymer Synthesized Through Direct (Hetero)Arylation Polymerization.

PubMed

Chávez, Patricia; Bulut, Ibrahim; Fall, Sadiara; Ibraikulov, Olzhas A; Chochos, Christos L; Bartringer, Jérémy; Heiser, Thomas; Lévêque, Patrick; Leclerc, Nicolas

2018-05-25

In this work, a new n -type polymer based on a thiazole-diketopyrrolopyrrole unit has been synthesized through direct (hetero)arylation polycondensation. The molar mass has been optimized by systematic variation of the the monomer concentration. Optical and electrochemical properties have been studied. They clearly suggested that this polymer possess a high electron affinity together with a very interesting absorption band, making it a good non-fullerene acceptor candidate. As a consequence, its charge transport and photovoltaic properties in a blend with the usual P3HT electron-donating polymer have been investigated.

Manganese and the limits of high potential phototrophy

NASA Astrophysics Data System (ADS)

Fischer, W. W.; Hemp, J.; Johnson, J. E.

2013-12-01

Photosynthetic reaction centers create high-energy electrons using light, harnessing the charge separation to simultaneously provide the cell with a strong oxidant and strong reductant. Many substrates can be used as electron donors for phototrophy, however there appears to be important energetic limits. In oxygenic photosynthesis photosystem II (PSII) provides a very strong oxidant that is capable of oxidizing water (ca. +830 mV) to molecular oxygen at the water-oxidizing complex, a redox-active tetra-manganese cluster. Anoxygenic photosystems however appear to only be able to oxidize lower potential electron donors (Fe2+, H2, S0, HS, S2O32-, NO2-, AsO33-).. Several transitional photosystems have been proposed as evolutionary intermediates between anoxygenic and oxygenic photosynthesis, with electron donors of higher redox potentials such as nitrite (ca. +431 mV) or Mn2+ (ca. +780 mV) bridging the redox gap to water. While a range of observations from the geological record support a Mn2+-based transitional photosystem (Johnson et al. 2013), this proposed photochemical scheme is distinct from that observed in anoxygenic photosynthetic organisms. Mechanistically all anoxygenic reaction centers receive their electrons indirectly via soluble electron carriers such as cytochrome c, high potential iron sulfur proteins or cupredoxins. Conversely Mn2+ oxidation is only known to occur today via direct oxidation, such as during photoassembly of the water-oxidizing complex of PSII, or by two distinct, non-energy-conserving mechanisms using molecular oxygen. No natural photosystem is known to solely perform Mn2+-oxidation. The highest redox-potential accessed by known anoxygenic phototrophs oxidizes nitrite (Schott et al. 2010), but it has been unclear until now whether the reaction center is specially adapted to produce high potential oxidants, similar to that of PSII to oxidize Mn2+ and water. To constrain this we sequenced the genome of the nitrite-oxidizing phototroph Thiocapsa sp. KS1. The data reveal that a type II reaction center that looks identical to other closely related strains that lack such a high potential metabolism. Unlike the direct Mn2+ oxidation, nitrite oxidation appears to require no special mutations, implying that nitrite oxidation occurs via cytochromes or cupredoxins, in family with other anoxygenic electron donations. These results define a broad limit for high potential electron donors for anoxygenic photosynthesis, and indicate that only Mn2+--oxidizing photosynthesis (prior to water oxidation by oxygenic phototrophs) likely requires a direct interaction with the reaction center. Johnson JE, Webb SM, Thomas K, Ono S, Kirschvink JL, Fischer WW (2013) Manganese-oxidizing photosynthesis before the rise of cyanobacteria, PNAS, Schott J, Griffin BM, Schink B (2010) Anaerobic phototrophic nitrite oxidation by Thiocapsa sp. strain KS1 and Rhodopseudomonas sp. strain LQ17, Microbiology, 156, 2428-2437.

Asymmetrical squaraines for high-performance small-molecule organic solar cells with a short circuit current of over 12 mA cm(-2).

PubMed

Chen, Yao; Zhu, Youqin; Yang, Daobin; Luo, Qian; Yang, Lin; Huang, Yan; Zhao, Suling; Lu, Zhiyun

2015-04-11

An asymmetrical squaraine dye (Py-3) with its two electron-donating aryl groups directly linked to the electron-withdrawing squaric acid core possesses an ideal bandgap of 1.33 eV, together with an intense and broad absorption band in the range 550-950 nm. Hence, the resulting solution-processed solar cells display an impressive Jsc of 12.03 mA cm(-2) and a PCE of 4.35%.

Electronic effects on the catalytic disproportionation of formic acid to methanol by [Cp*Ir(III)(R-bpy)Cl]Cl complexes.

PubMed

Sasayama, A F; Moore, C E; Kubiak, C P

2016-02-14

A series of [Cp*Ir(III)(R-bpy)Cl]Cl (R-bpy = 4,4'-di-R-2,2'-bipyridine; R = CF3, H, Me, tBu, OMe) complexes was prepared and studied for catalytic formic acid disproportionation. The relationship between the electron donating strength of the bipyridine substituents and methanol production of the corresponding complexes was analyzed; the unsubstituted (R = H) complex was the most selective for methanol formation.

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

Park Y. S.; Kale, T.; Wu, Q.

A series of diketopyrrolopyrrole(DPP)-based small molecules have been synthesized by palladium-catalyzed coupling reactions. Electron-donating moieties (benzothiophene, benzoselenophene, and benzotellurophene) are bridged by an electron-withdrawing DPP unit to generate donor-acceptor-donor (D-A-D) type molecules. We observe red-shifts in absorption spectra of these compounds by varying heteroatoms from sulfur to tellurium. In bulk heterojunction solar cells with [6,6]phenyl-C61-butyric acid methyl ester (PC61BM) as acceptor, we obtain power conversion efficiencies of 2.4% (benzothiophene), 4.1% (benzoselenophene), and 3.0% (benzotellurophene), respectively.

Microwave-Assisted Organocatalytic Intramolecular Knoevenagel/Hetero Diels-Alder Reaction with O-(Arylpropynyloxy)-Salicylaldehydes: Synthesis of Polycyclic Embelin Derivatives.

PubMed

Martín-Acosta, Pedro; Feresin, Gabriela; Tapia, Alejandro; Estévez-Braun, Ana

2016-10-21

A highly efficient and regioselective approach to new polycyclic embelin derivatives through a domino Knoevenagel condensation/intramolecular hetero Diels-Alder reaction using O-(arylpropynyloxy)-salicylaldehydes in the presence of ethylenediamine diacetate (EDDA) is reported. This organocatalyzed protocol is compatible toward a wide range of aryl-substituted alkynyl ethers with electron-donating and electron-withdrawing groups. When other active methylene compounds were subjected to this domino reaction the corresponding adducts were obtained in high yield.

7 CFR 1499.13 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... FAS. (b) A participant shall, within 30 days after export of all or a portion of the donated commodities, submit evidence of such export to FAS, in the manner set forth in the agreement. The evidence may be submitted through an electronic media approved by FAS or by providing the carrier's on board bill...

7 CFR 1499.13 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... FAS. (b) A participant shall, within 30 days after export of all or a portion of the donated commodities, submit evidence of such export to FAS, in the manner set forth in the agreement. The evidence may be submitted through an electronic media approved by FAS or by providing the carrier's on board bill...

A density functional theory study of the correlation between analyte basicity, ZnPc adsorption strength, and sensor response.

PubMed

Tran, N L; Bohrer, F I; Trogler, W C; Kummel, A C

2009-05-28

Density functional theory (DFT) simulations were used to determine the binding strength of 12 electron-donating analytes to the zinc metal center of a zinc phthalocyanine molecule (ZnPc monomer). The analyte binding strengths were compared to the analytes' enthalpies of complex formation with boron trifluoride (BF(3)), which is a direct measure of their electron donating ability or Lewis basicity. With the exception of the most basic analyte investigated, the ZnPc binding energies were found to correlate linearly with analyte basicities. Based on natural population analysis calculations, analyte complexation to the Zn metal of the ZnPc monomer resulted in limited charge transfer from the analyte to the ZnPc molecule, which increased with analyte-ZnPc binding energy. The experimental analyte sensitivities from chemiresistor ZnPc sensor data were proportional to an exponential of the binding energies from DFT calculations consistent with sensitivity being proportional to analyte coverage and binding strength. The good correlation observed suggests DFT is a reliable method for the prediction of chemiresistor metallophthalocyanine binding strengths and response sensitivities.

Density functional study of hypophosphite adsorption on Ni (1 1 1) and Cu (1 1 1) surfaces

NASA Astrophysics Data System (ADS)

Zeng, Yue; Liu, Shubin; Ou, Lihui; Yi, Jianlong; Yu, Shanci; Wang, Huixian; Xiao, Xiaoming

2006-02-01

Surface structures and electronic properties of hypophosphite, H 2PO 2-, molecularly adsorbed on Ni(1 1 1) and Cu(1 1 1) surfaces are investigated in this work by density functional theory at B3LYP/6-31++g(d, p) level. We employ a four-metal-atom cluster as the simplified model for the surface and have fully optimized the geometry and orientation of H 2PO 2- on the metal cluster. Six stable orientations have been discovered on both Ni (1 1 1) and Cu (1 1 1) surfaces. The most stable orientation of H 2PO 2- was found to have its two oxygen atoms interact the surface with two P sbnd O bonds pointing downward. Results of the Mulliken population analysis showed that the back donation from 3d orbitals of the transition metal substrate to the unfilled 3d orbital of the phosphorus atom in H 2PO 2- and 4s orbital's acceptance of electron donation from one lone pair of the oxygen atom in H 2PO 2- play very important roles in the H 2PO 2- adsorption on the transition metals. The averaged electron configuration of Ni in Ni 4 cluster is 4s 0.634p 0.023d 9.35 and that of Cu in Cu 4 cluster is 4s 1.004p 0.033d 9.97. Because of this subtle difference of electron configuration, the adsorption energy is larger on the Ni surface than on the Cu surface. The amount of charge transfers due to above two donations is larger from H 2PO 2- to the Ni surface than to the Cu surface, leading to a more positively charged P atom in Ni nH 2PO 2- than in Cu nH 2PO 2-. These results indicate that the phosphorus atom in Ni nH 2PO 2- complex is easier to be attacked by a nucleophile such as OH - and subsequent oxidation of H 2PO 2- can take place more favorably on Ni substrate than on Cu substrate.

Enzymatic cellulose oxidation is linked to lignin by long-range electron transfer

PubMed Central

Westereng, Bjørge; Cannella, David; Wittrup Agger, Jane; Jørgensen, Henning; Larsen Andersen, Mogens; Eijsink, Vincent G.H.; Felby, Claus

2015-01-01

Enzymatic oxidation of cell wall polysaccharides by lytic polysaccharide monooxygenases (LPMOs) plays a pivotal role in the degradation of plant biomass. While experiments have shown that LPMOs are copper dependent enzymes requiring an electron donor, the mechanism and origin of the electron supply in biological systems are only partly understood. We show here that insoluble high molecular weight lignin functions as a reservoir of electrons facilitating LPMO activity. The electrons are donated to the enzyme by long-range electron transfer involving soluble low molecular weight lignins present in plant cell walls. Electron transfer was confirmed by electron paramagnetic resonance spectroscopy showing that LPMO activity on cellulose changes the level of unpaired electrons in the lignin. The discovery of a long-range electron transfer mechanism links the biodegradation of cellulose and lignin and sheds new light on how oxidative enzymes present in plant degraders may act in concert. PMID:26686263

Association of mGFR of the Remaining Kidney Divided by Its Volume before Donation with Functional Gain in mGFR among Living Kidney Donors.

PubMed

Courbebaisse, Marie; Gaillard, François; Tissier, Anne-Marie; Fournier, Catherine; Le Nestour, Alexis; Corréas, Jean-Michel; Slimani-Thevenet, Hind; Martinez, Frank; Léon, Carine; Eladari, Dominique; Timsit, Marc-Olivier; Otal, Philippe; Hignette, Chantal; Friedlander, Gérard; Méjean, Arnaud; Houillier, Pascal; Kamar, Nassim; Legendre, Christophe

2016-08-08

The predictors of long-term renal function in living kidney donors are currently discussed. Our objectives were to describe the predictors of functional gain of the remaining kidney after kidney donation. We hypothesized that GFR of the remaining kidney divided by volume of this kidney (rk-GFR/vol) would reflect the density of functional nephrons and be inversely associated with functional gain of the remaining kidney. We conducted a prospective monocentric study including 63 living donors (26 men; 50.3±11.8 years old) who had been evaluated for (51)Cr-EDTA and measured GFR, split renal function by scintigraphy before donation (between 2004 and 2009), and measured GFR at 5.7±0.5 years after donation. For 52 donors, volume of the remaining kidney (measured and estimated with the ellipsoid formula using renal computed tomography scannography) was determined before donation. We tested our hypothesis in an external validation cohort of 39 living donors (13 men; 51.0±9.4 years old) from another single center during the same time period. For the main cohort, the mean measured GFR was 97.6±13.0 ml/min per 1.73 m(2) before donation and 63.8±9.4 ml/min per 1.73 m(2) at 5 years. Functional gain averaged 16.2±7.2 ml/min per 1.73 m(2) (+35.3%±16.7%). Multivariate analysis showed that age, body mass index, and rk-GFR/vol at donation were negatively correlated with functional gain and had strong predictive power of the 5-year functional gain (adjusted 5-year functional gain for age: -0.4 [95% confidence interval (95% CI), -0.5 to -0.1]; body mass index: -0.3 [95% CI, -0.6 to -0.1]; rk-GFR/vol: -55.1 [95% CI, -92.3 to -17.9]). We tested this model in the external validation cohort (adjusted 5-year functional gain for age: -0.1 [95% CI, -0.5 to 0.3]; body mass index: -0.9 [95% CI, -1.8 to -0.1]; rk-GFR/vol: -97.6 [95% CI, -137.5 to -57.6]) and confirmed that rk-GFR/vol was inversely associated with 5-year functional gain. For given age and body mass index, the long-term functional gain of the remaining kidney is inversely associated with the new variable rk-GFR/vol at donation. Copyright © 2016 by the American Society of Nephrology.

Synthesis and investigation of various properties of a novel series of nonlinear optical (NLO) chromophores bearing dicyanovinyl (DCV) moiety

NASA Astrophysics Data System (ADS)

Seferoğlu, Nurgul; Bayrak, Yasmina; Yalçın, Ergin; Seferoğlu, Zeynel

2017-12-01

A series of new nonlinear optic (NLO) chromophores containing a dimethine (vinyl) as π-bridge and electron acceptor dicyanomethine and different electron-donating groups and heterocyclic rings were synthesized. The structures of synthesized dyes were characterized by Fourier Transform Infrared (FTIR), proton and carbon nuclear magnetic resonance (1H/13C NMR) and mass spectrometry. Their electronic absorption spectra were evaluated in MeOH, THF and DCM. The absorption maxima exhibited little bathochromic shifts for each dye with the increasing dielectric constants of the solvents. The synthesized dyes can absorb in the range of 354-506 nm. The analysis of the electronic spectra showed that the dyes having electron-donating groups or heterocyclic rings showed significant changes relative to the model dye which has no substituent on the phenyl ring. In addition, the absorption maxima moved to the longest wavelength for dye containing N,N-dibutylamino substituent. Experimental absorption wavelengths for the compounds were found to be in good agreement with those predicted using the Time-Dependent Density Functional Theory (TD-DFT) [B3LYP/6-311 + g(d,p)]. Furthermore, the second order NLO responses of the dyes were calculated using density functional theory (DFT) calculations. The study reveals that the synthesized chromophores have large first hyperpolarizability (β) values, hence they may have potential applications in the development of NLO materials. For determination of the thermal behaviors of the compounds, thermogravimetric analysis (TGA) were done. The result showed that all the chromophores exhibited good thermal stabilities with the decomposition temperatures (Td) greater than 260 °C.

Substituent and Solvent Effects on the Absorption Spectra of Cation-π Complexes of Benzene and Borazine: A Theoretical Study.

PubMed

Sarmah, Nabajit; Bhattacharyya, Pradip Kr; Bania, Kusum K

2014-05-29

Time-dependent density functional theory (TDDFT) has been used to predict the absorption spectra of cation-π complexes of benzene and borazine. Both polarized continuum model (PCM) and discrete solvation model (DSM) and a combined effect of PCM and DSM on the absorption spectra have been elucidated. With decrease in size of the cation, the π → π* transitions of benzene and borazine are found to undergo blue and red shift, respectively. A number of different substituents (both electron-withdrawing and electron-donating) and a range of solvents (nonpolar to polar) have been considered to understand the effect of substituent and solvents on the absorption spectra of the cation-π complexes of benzene and borazine. Red shift in the absorption spectra of benzene cation-π complexes are observed with both electron-donating groups (EDGs) and electron-withdrawing groups (EWGs). The same trend has not been observed in the case of substituted borazine cation-π complexes. The wavelength of the electronic transitions corresponding to cation-π complexes correlates well with the Hammet constants (σ p and σ m ). This correlation indicates that the shifting of spectral lines of the cation-π complexes on substitution is due to both resonance and inductive effect. On incorporation of solvent phases, significant red or blue shifting in the absorption spectra of the complexes has been observed. Kamlet-Taft multiparametric equation has been used to explain the effect of solvent on the absorption spectra of complexes. Polarity and polarizability are observed to play an important role in the solvatochromism of the cation-π complexes.

Neighbouring group processes in the deamination of protonated phenylalanine derivatives.

PubMed

Lioe, Hadi; O'Hair, Richard A J

2005-10-21

The gas-phase fragmentation of protonated phenylalanine and a series of its derivatives (tyrosine, 4-methylphenylalanine, 4-aminophenylalanine, 4-methoxyphenylalanine, 4-tert-butylphenylalanine, 4-fluorophenylalanine, 4-chlorophenylalanine, 4-bromophenylalanine, 4-iodophenylalanine, 4-cyanophenylalanine, 4-nitrophenylalanine, 3-fluorophenylalanine, and 3,4-dichlorophenylalanine) were examined using a combination of low energy CID in a quadrupole ion trap mass spectrometer as well as DFT calculations and RRKM modelling. In particular, the relationship between the electron-donating ability of the substituent and the competitive losses of H2O + CO and NH3 were explored through the application of the Hammett equation. It was found that electron-donating substituents promote the loss of NH3, while electron-withdrawing substituents suppress the loss of NH3 and favour the H2O + CO loss fragmentation channel instead. These observations are consistent with a neighbouring group pathway operating for the loss of NH3. Molecular orbital calculation (at the B3LYP/6-31+G(d,p) level of theory) were also performed for a range of derivatives to compare the relative transition state energy barriers for three competing mechanisms: (i) the combined loss of H2O + CO, which is triggered by an initial intramolecular proton transfer from the ammonium group to hydroxyl OH, followed by the combined loss of H2O and CO to form an immonium ion; (ii) loss of NH3 via an aryl assisted neighbouring group pathway to yield a phenonium ion; (iii) loss of NH3 via a 1,2-hydride migration process, which results in the formation of a benzyl cation. The relative energy barriers for H2O + CO loss remain nearly constant, while that for both NH3 pathways increase as the substituent moves from electron-donating to electron-withdrawing. The relative transition state energy for loss of NH3 via the aryl assisted neighbouring group pathway is always lower than that of the 1,2-hydride migration process. RRKM modelling of the DFT predicted barrier heights suggest that the rate constants for H2O + CO loss are insensitive to the substituent on the ring, while the NH3 loss channels are greatly affected by the substituent. These theoretical results are consistent with the experimental observation of the relative yields of the competing fragmentation channels. Finally, comparisons with published gas phase and condensed phase studies on related systems are made.

Effect of electron donating groups on polyphenol-based antioxidant dendrimers.

PubMed

Lee, Choon Young; Nanah, Cyprien N; Held, Rich A; Clark, Amanda R; Huynh, Uyen G T; Maraskine, Marina C; Uzarski, Rebecca L; McCracken, John; Sharma, Ajit

2015-04-01

Numerous studies have reported the beneficial effects of antioxidants in human diseases. Among their biological effects, a majority of antioxidants scavenge reactive radicals in the body, thereby reducing oxidative stress that is associated with the pathogenesis of many diseases. Antioxidant dendrimers are a new class of potent antioxidant compounds reported recently. In this study, six polyphenol-based antioxidant dendrimers with or without electron donating groups (methoxy group) were synthesized in order to elucidate the influence of electron donating groups (EDG) on their antioxidant activities. Syringaldehyde (2 ortho methoxy groups), vanillin (1 ortho methoxy group), and 4-hydroxybenzaldehyde (0 methoxy group) were derivatized with propargylamine to form building blocks for the dendrimers. All the six dendrimers contain polyether cores, which were synthesized by attaching pentaerythritol and methyl α-d-glucopyranoside to in-house prepared spacer units. To prepare generation 1 antioxidant dendrimers, microwave energy and granulated metallic copper catalyst were used to link the cores and building blocks together via alkyne-azide 1,3-cycloaddition click chemistry. These reaction conditions resulted in high yields of the target dendrimers that were free from copper contamination. Based on DPPH antioxidant assay, antioxidant dendrimers decorated with syringaldehyde and vanillin exhibited over 70- and 170-fold increase in antioxidant activity compared to syringaldehyde and vanillin, respectively. The antioxidant activity of dendrimers increased with increasing number of EDG groups. Similar results were obtained when the dendrimers were used to protect DNA and human LDL against organic carbon and nitrogen-based free radicals. In addition, the antioxidant dendrimers did not show any pro-oxidant activity on DNA in the presence of physiological amounts of copper. Although the dendrimers showed potent antioxidant activities against carbon and nitrogen free radicals, EPR and DNA protection studies revealed lack of effectiveness of these dendrimers against hydroxyl radicals. The dendrimers were not cytotoxic to CHO-K1 cells. Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

A Reliable Hybrid Adsorbent for Efficient Radioactive Cesium Accumulation from Contaminated Wastewater

PubMed Central

Awual, Md. Rabiul; Yaita, Tsuyoshi; Miyazaki, Yuji; Matsumura, Daiju; Shiwaku, Hideaki; Taguchi, Tomitsugu

2016-01-01

Cesium (Cs) removal from nuclear liquid wastewater has become an emerging issue for safeguarding public health after the accident at the Fukushima Daiichi Nuclear Power Plant. A novel macrocyclic ligand of o-benzo-p-xylyl-22-crown-6-ether (OBPX22C6) was developed and successfully immobilized onto mesoporous silica for the preparation of hybrid adsorbent. The benzene ring π electron is the part of crown ether of OBPX22C6 for easy orientation of the macrocyclic compound for making the π electron donation with Cs complexation. The potential and feasibility of the hybrid adsorbent as being Cs selective was evaluated in terms of sensitivity, selectivity and reusability. The results clarified that the Cs removal process was rapid and reached saturation within a short time. Considering the effect of competitive ions, sodium (Na) did not markedly affect the Cs adsorption whereas potassium (K) was slightly affected due to the similar ionic radii. However, the oxygen in long ethylene glycol chain in OBPX22C6 was expected to show strong coordination, including Cs-π interaction with Cs even in the presence of the high amount of K and Na. Due to its high selectivity and reusability, significant volume reduction is expected as this promising hybrid adsorbent is used for Cs removal in Fukushima wastewater. PMID:26818070

Computational design of bio-inspired carnosine-based HOBr antioxidants

NASA Astrophysics Data System (ADS)

Sarrami, Farzaneh; Yu, Li-Juan; Karton, Amir

2017-10-01

During a respiratory burst the enzyme myeloperoxidase generates significant amounts of hypohalous acids (HOX, X = Cl and Br) in order to inflict oxidative damage upon invading pathogens. However, excessive production of these potent oxidants is associated with numerous inflammatory diseases. It has been suggested that the endogenous antioxidant carnosine is an effective HOCl scavenger. Recent computational and experimental studies suggested that an intramolecular Cl+ transfer from the imidazole ring to the terminal amine might play an important role in the antioxidant activity of carnosine. Based on high-level ab initio calculations, we propose a similar reaction mechanism for the intramolecular Br+ transfer in carnosine. These results suggest that carnosine may be an effective HOBr scavenger. On the basis of the proposed reaction mechanism, we proceed to design systems that share similar structural features to carnosine but with enhanced HOX scavenging capabilities for X = Cl and Br. We find that (i) elongating the β-alanyl-glycyl side chain by one carbon reduces the reaction barriers by up to 44%, and (ii) substituting the imidazole ring with strong electron-donating groups reduces the reaction barriers by similar amounts. We also show that the above structural and electronic effects are largely additive. In an antioxidant candidate that involves both of these effects the reaction barriers are reduced by 71%.

Light-induced charge separation across bio-inorganic interface.

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

Dimitrijevic, N. M.; Rajh, T.; De La Garza, L.

Rational design of hybrid biomolecule - nanoparticulate semiconductor conjugates enables coupling of functionality of biomolecules with the capability of semiconductors for solar energy capture, that can have potential application in energy conversion, sensing and catalysis. The particular challenge is to obtain efficient charge separation analogous to the natural photosynthesis process. The synthesis of axially anisotropic TiO{sub 2} nano-objects such as tubes, rods and bricks, as well as spherical and faceted nanoparticles has been developed in our laboratory. Depending on their size and shape, these nanostructures exhibit different domains of crystallinity, surface areas and aspect ratios. Moreover, in order to accommodatemore » for high curvature in nanoscale regime, the surfaces of TiO{sub 2} nano-objects reconstructs resulting in changes in the coordination of surface Ti atoms from octahedral (D{sub 2d}) to square pyramidal structures (C{sub 4v}). The formation of these coordinatively unsaturated Ti atoms, thus depends strongly on the size and shape of nanocrystallites and affects trapping and reactivity of photogenerated charges. We have exploited these coordinatively unsaturated Ti atoms to coupe electron-donating (such as dopamine) and electron-accepting (pyrroloquinoline quinone) conductive linkers that allow wiring of biomolecules and proteins resulting in enhanced charge separation which increases the yield of ensuing chemical transformations.« less

A Reliable Hybrid Adsorbent for Efficient Radioactive Cesium Accumulation from Contaminated Wastewater.

PubMed

Awual, Md Rabiul; Yaita, Tsuyoshi; Miyazaki, Yuji; Matsumura, Daiju; Shiwaku, Hideaki; Taguchi, Tomitsugu

2016-01-28

Cesium (Cs) removal from nuclear liquid wastewater has become an emerging issue for safeguarding public health after the accident at the Fukushima Daiichi Nuclear Power Plant. A novel macrocyclic ligand of o-benzo-p-xylyl-22-crown-6-ether (OBPX22C6) was developed and successfully immobilized onto mesoporous silica for the preparation of hybrid adsorbent. The benzene ring π electron is the part of crown ether of OBPX22C6 for easy orientation of the macrocyclic compound for making the π electron donation with Cs complexation. The potential and feasibility of the hybrid adsorbent as being Cs selective was evaluated in terms of sensitivity, selectivity and reusability. The results clarified that the Cs removal process was rapid and reached saturation within a short time. Considering the effect of competitive ions, sodium (Na) did not markedly affect the Cs adsorption whereas potassium (K) was slightly affected due to the similar ionic radii. However, the oxygen in long ethylene glycol chain in OBPX22C6 was expected to show strong coordination, including Cs-π interaction with Cs even in the presence of the high amount of K and Na. Due to its high selectivity and reusability, significant volume reduction is expected as this promising hybrid adsorbent is used for Cs removal in Fukushima wastewater.

Mitochondrial pharmacology: electron transport chain bypass as strategies to treat mitochondrial dysfunction.

PubMed

Atamna, Hani; Mackey, Jeanette; Dhahbi, Joseph M

2012-01-01

Mitochondrial dysfunction (primary or secondary) is detrimental to intermediary metabolism. Therapeutic strategies to treat/prevent mitochondrial dysfunction could be valuable for managing metabolic and age-related disorders. Here, we review strategies proposed to treat mitochondrial impairment. We then concentrate on redox-active agents, with mild-redox potential, who shuttle electrons among specific cytosolic or mitochondrial redox-centers. We propose that specific redox agents with mild redox potential (-0.1 V; 0.1 V) improve mitochondrial function because they can readily donate or accept electrons in biological systems, thus they enhance metabolic activity and prevent reactive oxygen species (ROS) production. These agents are likely to lack toxic effects because they lack the risk of inhibiting electron transfer in redox centers. This is different from redox agents with strong negative (-0.4 V; -0.2 V) or positive (0.2 V; 0.4 V) redox potentials who alter the redox status of redox-centers (i.e., become permanently reduced or oxidized). This view has been demonstrated by testing the effect of several redox active agents on cellular senescence. Methylene blue (MB, redox potential ≅10 mV) appears to readily cycle between the oxidized and reduced forms using specific mitochondrial and cytosolic redox centers. MB is most effective in delaying cell senescence and enhancing mitochondrial function in vivo and in vitro. Mild-redox agents can alter the biochemical activity of specific mitochondrial components, which then in response alters the expression of nuclear and mitochondrial genes. We present the concept of mitochondrial electron-carrier bypass as a potential result of mild-redox agents, a method to prevent ROS production, improve mitochondrial function, and delay cellular aging. Thus, mild-redox agents may prevent/delay mitochondria-driven disorders. Copyright © 2012 International Union of Biochemistry and Molecular Biology, Inc.

Correlation among Singlet-Oxygen Quenching, Free-Radical Scavenging, and Excited-State Intramolecular-Proton-Transfer Activities in Hydroxyflavones, Anthocyanidins, and 1-Hydroxyanthraquinones.

PubMed

Nagaoka, Shin-Ichi; Bandoh, Yuki; Nagashima, Umpei; Ohara, Keishi

2017-10-26

Singlet-oxygen ( 1 O 2 ) quenching, free-radical scavenging, and excited-state intramolecular proton-transfer (ESIPT) activities of hydroxyflavones, anthocyanidins, and 1-hydroxyanthraquinones were studied by means of laser, stopped-flow, and steady-state spectroscopies. In hydroxyflavones and anthocyanidins, the 1 O 2 quenching activity positively correlates to the free-radical scavenging activity. The reason for this correlation can be understood by considering that an early step of each reaction involves electron transfer from the unfused phenyl ring (B-ring), which is singly bonded to the bicyclic chromen or chromenylium moiety (A- and C-rings). Substitution of an electron-donating OH group at B-ring enhances the electron transfer leading to activation of the 1 O 2 quenching and free-radical scavenging. In 3-hydroxyflavones, the OH substitution at B-ring reduces the activity of ESIPT within C-ring, which can be explained in terms of the nodal-plane model. As a result, the 1 O 2 quenching and free-radical scavenging activities negatively correlate to the ESIPT activity. A catechol structure at B-ring is another factor that enhances the free-radical scavenging in hydroxyflavones. In contrast to these hydroxyflavones, 1-hydroxyanthraquinones having an electron-donating OH substituent adjacent to the O-H---O═C moiety susceptible to ESIPT do not show a simple correlation between their 1 O 2 quenching and ESIPT activities, because the OH substitution modulates these reactions.

Removal of antibiotics from water in the coexistence of suspended particles and natural organic matters using amino-acid-modified-chitosan flocculants: A combined experimental and theoretical study.

PubMed

Jia, Shuying; Yang, Zhen; Ren, Kexin; Tian, Ziqi; Dong, Chang; Ma, Ruixue; Yu, Ge; Yang, Weiben

2016-11-05

Contamination of trace antibiotics is widely found in surface water sources. This work delineates removal of trace antibiotics (norfloxacin (NOR), sulfadiazine (SDZ) or tylosin (TYL)) from synthetic surface water by flocculation, in the coexistence of inorganic suspended particles (kaolin) and natural organic matter (humic acid, HA). To avoid extra pollution caused by petrochemical products-based modification reagents, environmental-friendly amino-acid-modified-chitosan flocculants, Ctrp and Ctyr, with different functional aromatic-rings structures were employed. Jar tests at various pHs exhibited that, Ctyr, owning phenol groups as electron donors, was favored for elimination of cationic NOR (∼50% removal; optimal pH: 6; optimal dosage: 4mg/L) and TYL (∼60% removal; optimal pH: 7; optimal dosage: 7.5mg/L), due to π-π electron donator-acceptor (EDA) effect and unconventional H-bonds. Differently, Ctrp with indole groups as electron acceptor had better removal rate (∼50%) of SDZ anions (electron donator). According to correlation analysis, the coexisted kaolin and HA played positive roles in antibiotics' removal. Detailed pairwise interactions in molecular level among different components were clarified by spectral analysis and theoretical calculations (density functional theory), which are important for both the structural design of new flocculants aiming at targeted contaminants and understanding the environmental behaviors of antibiotics in water. Copyright © 2016 Elsevier B.V. All rights reserved.

Theoretical Study of the H2-ML(+) Binding Energies

NASA Technical Reports Server (NTRS)

Maitre, Philippe; Bauschlicher, Charles W., Jr.

1993-01-01

The cooperative ligand effects are studied in MLH2(+) and the results are compared to the recent experiments of Kemper et al. The bonding in these compounds is principally electrostatic in origin; however, ligand to metal and metal to ligand donations are important, especially for H2. We show that differences arise among the vanadium, cobalt, and copper complexes which are due to 3d donation to H2. Electron correlation is required to describe the dative interaction, and we find that second order Moller-Plesset perturbation theory (MP2) yields a good description of these systems compared with higher levels of correlation (such as the modified coupled pair functional and coupled cluster approaches) and experiment. However, obtaining quantitative results requires higher levels of theory than MP2.

Fund-raising on the web: the effect of an electronic door-in-the-face technique on compliance to a request.

PubMed

Guéguen, Nicolas

2003-04-01

In an attempt to test the door-in-the-face (DITF) technique in a computer-mediated context, 1,607 men and women taken at random in various e-mail lists were solicited to visit a web site for the profit of a humanitarian organization. In DITF condition, subjects were first solicited by an exaggerated request and, after refusing, were solicited for a small donation. In control condition the donation solicitation was formulated directly. In all the cases, the request was manipulated by the order of the successive HTML pages of the site. Results show that the DITF procedure increase compliance to the last request. The theoretical implication of the effect of this technique in a computer-communication context is discussed.

Restless legs syndrome in blood donors.

PubMed

Ulfberg, Jan; Nyström, Birgitta

2004-03-01

Restless legs syndrome (RLS) may be a cause of significant sleep disturbance. In a Swedish survey, the prevalence of RLS has been estimated to be 5.8% among men and 11.4% among women. Blood donation may result in iron deficiency, which is hypothesized to be one substantial cause of RLS. Nine hundred and forty-six (618 men, 328 women) consecutive blood donors aged 18-64 years, who attended a blood donation unit in mid-Sweden, answered a questionnaire that included questions about sleep habits. Frequency of blood donation was recorded and intake of iron tablets was assessed. Red blood cell distribution width (RDW) was also recorded. The value of RDW increases in relation to iron deficiency. RLS affected 14.7% of male and 24.7% of female blood donors. The mean intake of iron among the blood donors after each blood donation was only 781 mg, although the recommended intake is 2000 mg. Among the women, 7.4% presented an RDW of >14.5%, which strongly indicates iron deficiency. In this group of women, 37.5% were affected by RLS. The female RLS-sufferers were more affected than the female non-RLS subjects by problems initiating sleep (P=0.006 maintaining sleep (P<0.0001) and were also less refreshed upon awakening (P<0.001). This study showed that RLS was common among female blood donors. Women with RLS were more iron-deficient than those without and were affected by impaired sleep.

The effect of functional groups on reduction and activation of quinone bioreductive agents by DT-diaphorase.

PubMed

Fourie, Jeanne; Oleschuk, Curtis J; Guziec, Frank; Guziec, Lynn; Fiterman, Derek J; Monterrosa, Cielo; Begleiter, Asher

2002-02-01

Bioreductive antitumor agents are an important class of anticancer drugs that include the clinically used drug, mitomycin C, and new agents such as EO9 and tirapazamine that have recently been tested in clinical trials. These agents require activation by reductive enzymes such as DT-diaphorase or NADPH:cytochrome P450 reductase. A major focus for improving cancer chemotherapy has been to increase the selectivity and targeting of antitumor drugs to tumor cells. Bioreductive antitumor agents are ideally suited to improving tumor selectivity by an enzyme-directed approach to tumor targeting. However, none of the bioreductive agents developed to date has been specific for activation by a single reductive enzyme. This is in part due to a lack of knowledge about structural factors that confer selectivity for activation by reductive enzymes. The purpose of this study was to investigate the ability of specific functional groups to modify reduction and activation of quinone bioreductive agents by DT-diaphorase. We used a series of model benzoquinone mustard (BM) bioreductive agents and compared the parent compound BM to MBM, which has a strong electron-donating methoxy group, MeBM, which has a weaker electron-donating methyl group, CBM, which has an electron-withdrawing chloro group, and PBM and its structural isomer, meta-PBM (m-PBM), which both have sterically bulky benzene rings attached to the quinone moiety. We determined the rate of reduction of these agents by purified human DT-diaphorase under hypoxic and aerobic conditions. We also measured the cytotoxic activity of these agents in human tumor cell lines with and without the DT-diaphorase inhibitor, dicoumarol. Under hypoxic conditions in vitro, the t(1/2) values for reduction of the analogs by purified DT-diaphorase were 4, 6, 8, 9, 10 and 21 min for BM, MeBM, CBM, MBM, PBM and m-PBM, respectively. Under aerobic conditions the rank order of redox cycling after two-electron reduction by DT-diaphorase was MBM > MeBM > BM approximately CBM approximately PBM approximately m-PBM. The rate of reduction by DT-diaphorase of HBM, a non-alkylating analog of BM, was similar to that of BM under hypoxic conditions, and the rate of redox cycling under aerobic conditions was comparable to that of BM, suggesting that structural changes to the cytotoxic group of these BMs do not affect DT-diaphorase-mediated reduction and redox cycling potential. MBM, MeBM and PBM were more toxic than BM in the NCI-H661 human non-small-cell lung cancer cells and SK-MEL-28 human melanoma cells, while CBM displayed significantly increased cytotoxic activity compared to BM only in the NCI H661 cells. m-PBM had similar cytotoxic activity compared with BM in both cell lines. These cell lines have moderate to high levels of DT-diaphorase activity. When cells were pretreated with the DT-diaphorase inhibitor, dicoumarol, the cytotoxic activity of BM increased while that of MBM decreased in both cell lines, suggesting that BM was inactivated by DT-diaphorase while MBM was activated by this enzyme. Pretreatment of the SK-MEL-28 melanoma cells with dicoumarol resulted in an increased cytotoxic activity of MeBM, but pretreatment of the NCI-H661 cells did not affect the cytotoxicity of MeBM. This suggests, that similar to the results with BM, DT-diaphorase is an inactivating enzyme for MeBM in the SK-MEL-28 cell line. Dicoumarol had no significant effect on the cytotoxicity of CBM, PBM or m-PBM in both cell lines. These studies demonstrated that functional groups can significantly affect the reduction and activation of bioreductive agents by DT-diaphorase. All the functional groups decreased the rate of reduction of the quinone group by DT-diaphorase. Since MeBM and MBM, with electron-donating functional groups, and CBM with an electron-withdrawing functional group had similar half-lives of reduction by DT-diaphorase, steric rather than electronic effects of the functional groups appear to be more important for modifying the rate of reduction by DT-diaphorase. Steric effects on reduction by DT-diaphorase were also influenced by the position of the functional group on the quinone ring moiety, as the reduction of m-PBM was much slower than the reduction of PBM. The electron-donating methoxy and methyl functional groups increased the ability of the reduced products of MBM and MeBM to undergo redox cycling. DT-diaphorase appeared to be an activating enzyme for MBM. This may have resulted in part from increased formation of reactive oxygen species resulting from the increased redox cycling by MBM. In contrast, DT-diaphorase was an inactivating enzyme for BM, and for MeBM in the SK-MEL-28 melanoma cells, possibly because the hydroquinone product of BM and MeBM may be less cytotoxic than the semiquinone produced by one-electron reduction by NADPH:cytochrome P450 reductase.

CO oxidation on Ru-Pt bimetallic nanoclusters supported on TiO2(101): The effect of charge polarization

NASA Astrophysics Data System (ADS)

Jia, Chuanyi; Zhong, Wenhui; Deng, Mingsen; Jiang, Jun

2018-03-01

Pt-based catalyst is widely used in CO oxidation, while its catalytic activity is often undermined because of the CO poisoning effect. Here, using density functional theory, we propose the use of a Ru-Pt bimetallic cluster supported on TiO2 for CO oxidation, to achieve both high activity and low CO poisoning effect. Excellent catalytic activity is obtained in a Ru1Pt7/TiO2(101) system, which is ascribed to strong electric fields induced by charge polarization between one Ru atom and its neighboring Pt atoms. Because of its lower electronegativity, the Ru atom donates electrons to neighboring Pt. This induces strong electric fields around the top-layered Ru, substantially promoting the adsorption of O2/CO + O2 and eliminating the CO poisoning effect. In addition, the charge polarization also drives the d-band center of the Ru1Pt7 cluster to up-shift to the Fermi level. For surface O2 activation/CO oxidation, the strong electric field and d-band center close to the Fermi level can promote the adsorption of O2 and CO as well as reduce the reaction barrier of the rate-determining step. Meanwhile, since O2 easily dissociates on Ru1Pt7/TiO2(101) resulting in unwanted oxidation of Ru and Pt, a CO-rich condition is necessary to protect the catalyst at high temperature.

Ab Initio Molecular Dynamics Studies on Substitution vs. Electron Transfer Reactions of Substituted Ketyl Radical Anions with Chloroalkanes: How Do the Two Products Form in a Borderline Mechanism?

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

Yamataka, H.; Aida, Misako; Dupuis, Michel

We present a qualitative analysis, based on ab initio molecular dynamics (MD) calculations, of the SN2/ET mechanistic spectrum for three reactions: (1) HC(CN)=O.- + CH3Cl, (2) HC(CN)=O.- + (CH3)2CHCl, and (3) H2C=O.- + CH3Cl, passing through their SN2-like transition states. The finite temperature (298 K) direct-MD simulations indicate that the trajectories for reaction 1 appear to have a propensity towards SN2 products, the propensity for trajectories for reaction 2 seems to be towards ET products, whereas trajectories for reaction 3 appear to show no particular propensity towards either ET or SN2 products. The mechanistic diversity is consistent with the electronmore » donating ability of the ketyl species and steric bulkiness of chloroalkanes. We find that the trajectories have characteristics that reflect strongly the types of process (SN2 trajectories in reactions 1 and 3 vs. ET trajectories in reactions 2 and 3). Trajectories that lead to SN2 products are simple with C-C bond formation and C-Cl bond breaking essentially completed within 50 fs. By contrast, trajectories leading to ET products are more complex with a sudden electron reorganization taking place within 15 - 30 fs and the major bonding changes and electron and spin reorganizations completed after 250 fs.« less

Electronically Strongly Coupled Divinylheterocyclic-Bridged Diruthenium Complexes.

PubMed

Pfaff, Ulrike; Hildebrandt, Alexander; Korb, Marcus; Oßwald, Steffen; Linseis, Michael; Schreiter, Katja; Spange, Stefan; Winter, Rainer F; Lang, Heinrich

2016-01-11

Complexes [{Ru(CO)Cl(PiPr3 )2 }2 (μ-2,5-(CH-CH)2 -(c) C4 H2 E] (E=NR; R=C6 H4 -4-NMe2 (10 a), C6 H4 -4-OMe (10 b), C6 H4 -4-Me (10 c), C6 H5 (10 d), C6 H4 -4-CO2 Et (10 e), C6 H4 -4-NO2 (10 f), C6 H3 -3,5-(CF3 )2 (10 g), CH3 (11); E=O (12), S (13)) are discussed. The solid state structures of four alkynes and two complexes are reported. (Spectro)electrochemical studies show a moderate influence of the nature of the heteroatom and the electron-donating or -withdrawing substituents R in 10 a-g on the electrochemical and spectroscopic properties. The CVs display two consecutive one-electron redox events with ΔE°'=350-495 mV. A linear relationship between ΔE°' and the σp Hammett constant for 10 a-f was found. IR, UV/Vis/NIR and EPR studies for 10(+) -13(+) confirm full charge delocalization over the {Ru}CH-CH-heterocycle-CH-CH{Ru} backbone, classifying them as Class III systems according to the Robin and Day classification. DFT-optimized structures of the neutral complexes agree well with the experimental ones and provide insight into the structural consequences of stepwise oxidations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Potential electron mediators to extract electron energies of RBC glycolysis for prolonged in vivo functional lifetime of hemoglobin vesicles.

PubMed

Kettisen, Karin; Bülow, Leif; Sakai, Hiromi

2015-04-15

Developing a functional blood substitute as an alternative to donated blood for clinical use is believed to relieve present and future blood shortages, and to reduce the risks of infection and blood type mismatching. Hemoglobin vesicle (HbV) encapsulates a purified and concentrated human-derived Hb solution in a phospholipid vesicle (liposome). The in vivo safety and efficacy of HbV as a transfusion alternative have been clarified. Auto-oxidation of ferrous Hb in HbV gradually increases the level of ferric methemoglobin (metHb) and impairs the oxygen transport capabilities. The extension of the functional half-life of HbV has recently been proposed using an electron mediator, methylene blue (MB), which acts as a shuttle between red blood cells (RBC) and HbV. MB transfers electron energies of NAD(P)H, produced by RBC glycolysis, to metHb in HbV. Work presented here focuses on screening of 15 potential electron mediators, with appropriate redox potential and water solubility, for electron transfer from RBC to HbV. The results are assessed with regard to the chemical properties of the candidates. The compounds examined in this study were dimethyl methylene blue (DMB), methylene green, azure A, azure B, azure C, toluidine blue (TDB), thionin acetate, phenazine methosulfate, brilliant cresyl blue, cresyl violet, gallocyanine, toluylene blue, indigo carmine, indigotetrasulfonate, and MB. Six candidates were found to be unsuitable because of their insufficient diffusion across membranes, or overly high or nonexistent reactivity with relevant biomolecules. However, 9 displayed favorable metHb reduction. Among the suitable candidates, phenothiazines DMB and TDB exhibited effectiveness like MB did. In comparison to MB, they showed faster reduction by electron-donating NAD(P)H, coupled with showing a lower rate of reoxidation in the presence of molecular oxygen. Ascertaining the best electron mediator can provide a pathway for extending the lifetime and efficiency of potential blood substitutes.

Fund-Raising While You Shop: A Look at Fund-Raising Sites on the Internet.

ERIC Educational Resources Information Center

Seydel, Angela

2000-01-01

Explains how school fund-raising can be done over the Internet through electronic commerce. Discusses online retailers who donate percentage of sales to schools who have registered; Web sites that coordinate online retailers for schools, who also take a percentage of the sales; loss of revenue for local businesses; and marketing. (LRW)

7 CFR 1599.13 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... prescribed by FAS. (b) A participant shall, within 30 days after export of all or a portion of the donated commodities, submit evidence of such export to FAS, in the manner set forth in the agreement. The evidence may be submitted through an electronic media approved by FAS or by providing the carrier's on board bill...

7 CFR 1599.13 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... prescribed by FAS. (b) A participant shall, within 30 days after export of all or a portion of the donated commodities, submit evidence of such export to FAS, in the manner set forth in the agreement. The evidence may be submitted through an electronic media approved by FAS or by providing the carrier's on board bill...

7 CFR 1599.13 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... prescribed by FAS. (b) A participant shall, within 30 days after export of all or a portion of the donated commodities, submit evidence of such export to FAS, in the manner set forth in the agreement. The evidence may be submitted through an electronic media approved by FAS or by providing the carrier's on board bill...

7 CFR 1599.13 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... prescribed by FAS. (b) A participant shall, within 30 days after export of all or a portion of the donated commodities, submit evidence of such export to FAS, in the manner set forth in the agreement. The evidence may be submitted through an electronic media approved by FAS or by providing the carrier's on board bill...

7 CFR 1599.13 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... prescribed by FAS. (b) A participant shall, within 30 days after export of all or a portion of the donated commodities, submit evidence of such export to FAS, in the manner set forth in the agreement. The evidence may be submitted through an electronic media approved by FAS or by providing the carrier's on board bill...

Employing NMR Spectroscopy To Evaluate Transmission of Electronic Effects in 4-Substituted Chalcones

NASA Astrophysics Data System (ADS)

Wachter-Jurcsak, Nanette; Zamani, Hossein

1999-05-01

Described is an organic synthesis experiment that demonstrates the electronic transmission by substituents. The effect of substitution at the para-position of the styryl ring of 1,3-diphenyl-2-propenones (chalcones) by typical electron-donating or -accepting groups can be observed by proton and carbon-13 NMR spectroscopy. A linear correlation is observed when the differences in chemical shift measurements for H are plotted against the corresponding Hammett substituent constant values. Good correlation between carbon-13 chemical shifts of the alpha carbon are also observed. The syntheses of the 4-substituted chalcones is presented as well as a brief discussion of the theory.

An analysis of first-time blood donors return behaviour using regression models.

PubMed

Kheiri, S; Alibeigi, Z

2015-08-01

Blood products have a vital role in saving many patients' lives. The aim of this study was to analyse blood donor return behaviour. Using a cross-sectional follow-up design of 5-year duration, 864 first-time donors who had donated blood were selected using a systematic sampling. The behaviours of donors via three response variables, return to donation, frequency of return to donation and the time interval between donations, were analysed based on logistic regression, negative binomial regression and Cox's shared frailty model for recurrent events respectively. Successful return to donation rated at 49·1% and the deferral rate was 13·3%. There was a significant reverse relationship between the frequency of return to donation and the time interval between donations. Sex, body weight and job had an effect on return to donation; weight and frequency of donation during the first year had a direct effect on the total frequency of donations. Age, weight and job had a significant effect on the time intervals between donations. Aging decreases the chances of return to donation and increases the time interval between donations. Body weight affects the three response variables, i.e. the higher the weight, the more the chances of return to donation and the shorter the time interval between donations. There is a positive correlation between the frequency of donations in the first year and the total number of return to donations. Also, the shorter the time interval between donations is, the higher the frequency of donations. © 2015 British Blood Transfusion Society.

Give blood today or save lives tomorrow: Matching decision and message construal level to maximize blood donation intentions.

PubMed

Czeizler, Amalia; Garbarino, Ellen

2017-01-01

The research extends construal theory by testing if a match between the temporal construal framing of a blood donation decision and a blood donation request leads to higher donation intentions than a mismatch. Results show participants considering future donation who read an abstract donation request have significantly higher donation intentions than those who read a concrete request. Conversely, participants considering donating today who read a concrete donation request have significantly higher donation intentions than those who read an abstract request. This study confirms the importance of matching the construal framing of the communication to the temporal framing of the decision.

Chemical Constraints Governing the Origin of Metabolism: The Thermodynamic Landscape of Carbon Group Transformations

NASA Technical Reports Server (NTRS)

Weber, Arthur L.; Fonda, Mark (Technical Monitor)

2001-01-01

The thermodynamics of organic chemistry under mild aqueous conditions was examined in order to begin to understand its influence on the structure and operation of metabolism and its antecedents. Free energies were estimated for four types reactions of biochemical importance carbon-carbon bond cleavage and synthesis, hydrogen transfer between carbon groups, dehydration of alcohol groups, and aldo-keto isomerization. The energies were calculated for mainly aliphatic groups composed of carbon, hydrogen, and oxygen. The energy values showed that (1) when carbon-carbon bond cleavage involves two different types of functional groups, transfer of the shared electron-pair to the more reduced carbon group is energetically favored over transfer to the more oxidized carbon group, and (2) the energy of carbon-carbon bond transformation is strongly dependent on the type of functional group that donates the shared electron-pair during cleavage, and the group that accepts the shared electron-pair during synthesis, and (3) the energetics of C-C bond transformation is determined primarily by the half-reaction energies of the couples: carbonyl/carboxylic acid, carboxylic acid/carbon dioxide, alcohol/carbonyl, and hydrocarbon/alcohol. The energy of hydrogen-transfer between carbon groups was found to depend on the functional group class of both the hydrogen-donor and hydrogen-acceptor. From these and other observations we concluded that the chemistry of the origin of metabolism (and to a lesser degree modem metabolism) is strongly constrained by the (1) limited disproportionation energy of organic substrates that can be dissipated in a few irreversible reactions, (2) the energy-dominance of few half-reaction couples in carbon-carbon bond transformation that establishes whether a chemical reaction is energetically irreversible, reversible or unfeasible, and (3) the dependence of the transformation-energy on the oxidation state of carbon groups (functional group type) which is contingent on prior reactions in the synthetic pathway.

Structure-Property Relationships for Tailoring Phenoxazines as Reducing Photoredox Catalysts.

PubMed

McCarthy, Blaine G; Pearson, Ryan M; Lim, Chern-Hooi; Sartor, Steven M; Damrauer, Niels H; Miyake, Garret M

2018-04-18

Through the study of structure-property relationships using a combination of experimental and computational analyses, a number of phenoxazine derivatives have been developed as visible light absorbing, organic photoredox catalysts (PCs) with excited state reduction potentials rivaling those of highly reducing transition metal PCs. Time-dependent density functional theory (TD-DFT) computational modeling of the photoexcitation of N-aryl and core modified phenoxazines guided the design of PCs with absorption profiles in the visible regime. In accordance with our previous work with N, N-diaryl dihydrophenazines, characterization of noncore modified N-aryl phenoxazines in the excited state demonstrated that the nature of the N-aryl substituent dictates the ability of the PC to access a charge transfer excited state. However, our current analysis of core modified phenoxazines revealed that these molecules can access a different type of CT excited state which we posit involves a core substituent as the electron acceptor. Modification of the core of phenoxazine derivatives with electron-donating and electron-withdrawing substituents was used to alter triplet energies, excited state reduction potentials, and oxidation potentials of the phenoxazine derivatives. The catalytic activity of these molecules was explored using organocatalyzed atom transfer radical polymerization (O-ATRP) for the synthesis of poly(methyl methacrylate) (PMMA) using white light irradiation. All of the derivatives were determined to be suitable PCs for O-ATRP as indicated by a linear growth of polymer molecular weight as a function of monomer conversion and the ability to synthesize PMMA with moderate to low dispersity (dispersity less than or equal to 1.5) and initiator efficiencies typically greater than 70% at high conversions. However, only PCs that exhibit strong absorption of visible light and strong triplet excited state reduction potentials maintain control over the polymerization during the entire course of the reaction. The structure-property relationships established here will enable the application of these organic PCs for O-ATRP and other photoredox-catalyzed small molecule and polymer syntheses.

Profile of Heart Donors from the Human Valve Bank of the Santa Casa de Misericórdia de Curitiba.

PubMed

Ferreira, Renata Maria; da Costa, Marise Teresinha Brenner Affonso; Canciglieri Junior, Osiris; Sant'Anna, Ângelo Márcio Oliveira

2016-04-01

Human heart valves are used as replacement valves and have satisfactory functional results compared with conventional prostheses. Characterize the profile of effective heart donors from the human valve bank of the santa casa de misericórdia de curitiba and analyze the association between the profile variables. It consists of a retrospective and quantitative study of electronic medical records from heart donors for heart valves. every heart donation made to the bank between january 2004 and december 2014 was studied. 2,149 donations were analyzed, from donors aged 0 to 71 years old, with an average of 34.9 ± 15.03 years old. most donors were male 65.7% (n=1,411) and 34.3% (n=738) were female. among the most frequent causes of the donors' death are trauma at 53% (n=1,139) and cerebral vascular accident at 34.2% (n=735). there was significant statistical association between the analyzed variables. There has been an improvement in brazil's donation rate, being essential that the tissue banks work together with the state and federal district centers for notification, procurement and distribution of organs in order to increase the number of donors.

Effect of media presentations on willingness to commit to organ donation.

PubMed

Harel, Inbal; Kogut, Tehila; Pinchas, Meir; Slovic, Paul

2017-05-16

We examine how presentations of organ donation cases in the media may affect people's willingness to sign organ donation commitment cards, donate the organs of a deceased relative, support the transition to an "opt-out" policy, or donate a kidney while alive. We found that providing identifying information about the prospective recipient (whose life was saved by the donation) increased the participants' willingness to commit to organ donation themselves, donate the organs of a deceased relative, or support a transition to an "opt-out" policy. Conversely, identifying the deceased donor tended to induce thoughts of death rather than about saving lives, resulting in fewer participants willing to donate organs or support measures that facilitated organ donation. A study of online news revealed that identification of the donor is significantly more common than identification of the recipient in the coverage of organ donation cases-with possibly adverse effects on the incidence of organ donations.

Electron doping through lithium intercalation to interstitial channels in tetrahedrally bonded SiC

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

Sakai, Yuki; Center for Computational Materials, Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, Texas 78712; Oshiyama, Atsushi

2015-11-07

We report on first-principles calculations that clarify the effect of lithium atom intercalation into zinc blende 3C-silicon carbide (3C-SiC) on electronic and structural properties. Lithium atoms inside 3C-SiC are found to donate electrons to 3C-SiC that is an indication of a new way of electron doping through the intercalation. The electrons doped into the conduction band interact with lithium cations and reduce the band spacing between the original valence and conduction bands. We have also found that a silicon monovacancy in 3C-SiC promotes the lithium intercalation, showing that the vacancy generation makes SiC as a possible anode material for lithium-ionmore » battery.« less

Regioselective copper-catalyzed N(1)-(hetero)arylation of protected histidine.

PubMed

Sharma, Krishna K; Mandloi, Meenakshi; Jain, Rahul

2016-09-26

We report regioselective N(1)-arylation of protected histidine using copper(i) iodide as a catalyst, trans-N,N'-dimethylcyclohexane-1,2-diamine as a ligand and readily available aryl iodides as coupling partners under microwave irradiation at 130 °C for 40 min. The reaction provides rapid access to electron-donating, electron-withdrawing and bulky group substituted N-arylated histidines in high yields, including previously inaccessible N-heteroaryl histidines. These N(1)-(hetero)aryl histidines are promising building blocks in peptide-based drug design and discovery.

Highly chromic, proton-responsive phenyl pyrimidones.

PubMed

Dhuguru, Jyothi; Gheewala, Chirag; Kumar, N S Saleesh; Wilson, James N

2011-08-19

Aryl pyrimidones are pharmacologically relevant compounds whose optical properties have only been partially explored. We report the synthesis and optical characterization of a series of aryl- and diaryl-2(1H)-pyrimidones. The electronic transitions of these chromophores are modulated by the extent of conjugation between the pendant phenyl ring and the pyrimidone core as well as the presence of electron-donating auxochromes. Monoprotonation of the pyrimidone ring results in large hyperchromic and bathochromic shifts as well as switching of fluorescence making these phenyl pyrimidones of interest as sensory materials. © 2011 American Chemical Society

Emission color tuning in AlQ3 complexes with extended conjugated chromophores.

PubMed

Pohl, Radek; Anzenbacher, Pavel

2003-08-07

[reaction: see text] A new method for the synthesis of 5-arylethynyl-8-hydroxyquinoline ligands using Sonogashira-Hagihara coupling was developed. The electronic nature of arylethynyl substituents affects the emission color and quantum yield of the resulting Al(III) complex. Photophysical properties of the metallocomplexes correspond to the electron-withdrawing/-donating character of the arylethynyl substituents. Optical properties of such Al(III) complexes correlate with the Hammett constant values of the respective substituents. This strategy offers a powerful tool for the preparation of electroluminophores with predictable photophysical properties.

New Stable Cu(I) Catalyst Supported on Weakly Acidic Polyacrylate Resin for Green C-N Coupling: Synthesis of N-(Pyridin-4-yl)benzene Amines and N,N-Bis(pyridine-4-yl)benzene Amines.

PubMed

Kore, Nitin; Pazdera, Pavel

2016-12-22

A method for preparation of a new stable Cu(I) catalyst supported on weakly acidic polyacrylate resin without additional stabilizing ligands is described. A simple and efficient methodology for Ullmann Cu(I) catalyzed C-N cross coupling reactions using this original catalyst is reported. Coupling reactions of 4-chloropyridinium chloride with anilines containing electron donating (EDG) or electron withdrawing (EWG) groups, naphthalen-2-amine and piperazine, respectively, are successfully demonstrated.

Effects of heteroatom substitution in conjugated heterocyclic compounds on photovoltaic performance: from sulfur to tellurium.

PubMed

Park, Y S; Kale, T S; Nam, C-Y; Choi, D; Grubbs, R B

2014-07-28

We report a general strategy for fine-tuning the bandgap of donor-acceptor-donor based organic molecules by modulating the electron-donating ability of the donor moiety by changing the benzochalcogenophene donor groups from benzothiophenes to benzoselenophenes to benzotellurophenes. These molecules show red-shifts in absorption and external quantum efficiency maxima from sulfur to selenium to tellurium. In bulk heterojunction solar cell devices, the benzoselenophene derivative shows a power conversion efficiency as high as 5.8% with PC61BM as the electron acceptor.

An investigation of the impact of Melbourne Zoo's "Seal-the-Loop" donate call-to-action on visitor satisfaction and behavior.

PubMed

Mellish, Sarah; Sanders, Ben; Litchfield, Carla A; Pearson, Elissa L

2017-05-01

Modern zoos are uniquely positioned to educate the public about environmental issues and promote conservation action. This report investigates the introduction of a donation request during an interactive fur seal presentation (as part of Melbourne Zoo's "Seal-the-Loop" initiative) on visitor satisfaction, perceptions of donation as a way to help wild fur seals, and donation behaviors. Comparisons are made between three groups surveyed upon exit: (1) viewed the interactive fur seal presentation prior to the donation request implementation (pledge-presentation: N = 86; see Mellish, Pearson, Sanders, and Litchfield []; International Zoo Yearbook 129:129-154); (2) viewed the interactive fur seal presentation including the donation request (donate-presentation: N = 82); and (3) viewed the fur seal exhibit and donation point but not the presentation and were not directly asked to make a donation (donate-exhibit: N = 82). Findings demonstrate visitor satisfaction with the interactive fur seal presentation was not negatively impacted following the implementation of the donate request (with >92% of pledge-presentation and donate-presentation visitors providing a "satisfied" or "very satisfied" rating). Only the donate-presentation visitors reported donation as a conservation action to help wild fur seals (19.18%; 0% for pledge-presentation visitors). While both donate-exhibit (39.51%) and donate-presentation visitors (60.75%) self-reported making donations or intending to do so, donation behavior was significantly increased for visitors who had viewed the fur seal presentation. Findings provide preliminary support that zoos may utilize interactive educational presentations to effectively ask visitors for donations to support specific conservation projects, without negatively impacting on satisfaction and with a relatively high level of visitor engagement. © 2017 Wiley Periodicals, Inc.

Improvement in likelihood to donate blood after being offered a topical anesthetic.

PubMed

Watanabe, Kyle M; Jay, Jeffrey; Alicto, Christopher; Yamamoto, Loren G

2011-02-01

While there are many reasons people choose not to donate blood, pain sustained during the venipuncture portion of the blood donation process is likely one deterrent to volunteer donation. The purpose of this study was to survey the improvement in likelihood of donation if participants were given the option of a topical anesthetic cream prior to venipuncture. Over a three month period 316 adults (convenience sample) completed a one page survey consisting of twelve questions pertaining to blood donation. Participants were asked about their likelihood of donating blood in the near future (No Possibility, Possible, Likely, Certain). They were then informed of the possibility of using a topical anesthetic cream prior to donation. Subsequently, their likelihood of donating blood was reassessed. Fifty (16%) subjects reported an increased likelihood of donating blood if offered a topical anesthetic (p〈0.0001). Of these respondents reporting an increase in donation likelihood, eleven improved by 2 or more likelihood categories. Amongst the 169 participants who never donated blood, 34 (20%) reported an increased likelihood of donation after being told about the topical anesthetic cream, compared to 16 (10%) of the 147 subjects who had previously donated blood (p=0.02). The findings of this study suggest that providing a topical anesthetic had a positive effect on the study participants' likelihood of donating blood. This improvement was greater amongst those who have never donated blood. Hawaii Medical Journal Copyright 2011.

Bicarbonate may Be required for ligation of manganese in the oxygen-evolving complex of photosystem II.

PubMed

Klimov, V V; Hulsebosch, R J; Allakhverdiev, S I; Wincencjusz, H; van Gorkom, H J; Hoff, A J

1997-12-23

It was previously shown in the photosystem II membrane preparation DT-20 that photoxidation of the oxygen-evolving manganese cluster was blocked by 0.1 mM formate, unless 0.2 mM bicarbonate was present as well [Wincencjusz, H., Allakhverdiev, S. I., Klimov, V. V., and Van Gorkom, H. J. (1996) Biochim. Biophys. Acta 1273, 1-3]. Here it is shown by measurements of EPR signal II that oxidation of the secondary electron donor, YZ, is not inhibited. However, the reduction of is greatly slowed and occurs largely by back reaction with reduced acceptors. Bicarbonate is shown to prevent the loss of fast electron donation to . The release of about one or two free Mn2+ per photosystem II during formate treatment, and the fact that these effects are mimicked by Mn-depletion, suggests that formate may act by replacing a bicarbonate which is essential for Mn binding. Irreversible light-induced rebinding in an EPR-silent form of Mn2+ that was added to Mn-depleted DT-20 was indeed found to depend on the presence of bicarbonate, as did the reconstitution in such material of both the fast electron donation to and the UV absorbance changes characteristic of a functional oxygen-evolving complex. It is concluded that bicarbonate may be an essential ligand of the functional Mn cluster.

Bio-inspired cofacial Fe porphyrin dimers for efficient electrocatalytic CO2 to CO conversion: Overpotential tuning by substituents at the porphyrin rings

PubMed Central

Zahran, Zaki N.; Mohamed, Eman A.; Naruta, Yoshinori

2016-01-01

Efficient reduction of CO2 into useful carbon resources particularly CO is an essential reaction for developing alternate sources of fuels and for reducing the greenhouse effect of CO2. The binuclear Ni, Fe−containing carbon monoxide dehydrogenase (CODHs) efficiently catalyzes the reduction of CO2 to CO. The location of Ni and Fe at proper positions allows their cooperation for CO2 to CO conversion through a push−pull mechanism. Bio−inspired from CODHs, we used several cofacial porphyrin dimers with different substituents as suitable ligands for holding two Fe ions with suitable Fe−Fe separation distance to efficiently and selectively promote CO2 to CO conversion with high turnover frequencies, TOFs. The substituents on the porphyrin rings greatly affect the catalysis process. By introducing electron-withdrawing/-donating groups, e.g. electron-withdrawing perfluorophenyl, at all meso positions of the porphyrin rings, the catalysis overpotential, η was minimized by ≈0.3 V compared to that obtained by introducing electron-donating mesityl groups. The Fe porphyrin dimers among reported catalysts are the most efficient ones for CO2 to CO conversion. Control experiments indicate that the high performance of the current CO2 to CO conversion catalysts is due to the presence of binuclear Fe centers at suitable Fe−Fe separation distance. PMID:27087483

Bio-inspired cofacial Fe porphyrin dimers for efficient electrocatalytic CO2 to CO conversion: Overpotential tuning by substituents at the porphyrin rings.

PubMed

Zahran, Zaki N; Mohamed, Eman A; Naruta, Yoshinori

2016-04-18

Efficient reduction of CO2 into useful carbon resources particularly CO is an essential reaction for developing alternate sources of fuels and for reducing the greenhouse effect of CO2. The binuclear Ni, Fe-containing carbon monoxide dehydrogenase (CODHs) efficiently catalyzes the reduction of CO2 to CO. The location of Ni and Fe at proper positions allows their cooperation for CO2 to CO conversion through a push-pull mechanism. Bio-inspired from CODHs, we used several cofacial porphyrin dimers with different substituents as suitable ligands for holding two Fe ions with suitable Fe-Fe separation distance to efficiently and selectively promote CO2 to CO conversion with high turnover frequencies, TOFs. The substituents on the porphyrin rings greatly affect the catalysis process. By introducing electron-withdrawing/-donating groups, e.g. electron-withdrawing perfluorophenyl, at all meso positions of the porphyrin rings, the catalysis overpotential, η was minimized by ≈0.3 V compared to that obtained by introducing electron-donating mesityl groups. The Fe porphyrin dimers among reported catalysts are the most efficient ones for CO2 to CO conversion. Control experiments indicate that the high performance of the current CO2 to CO conversion catalysts is due to the presence of binuclear Fe centers at suitable Fe-Fe separation distance.

Bio-inspired cofacial Fe porphyrin dimers for efficient electrocatalytic CO2 to CO conversion: Overpotential tuning by substituents at the porphyrin rings

NASA Astrophysics Data System (ADS)

Zahran, Zaki N.; Mohamed, Eman A.; Naruta, Yoshinori

2016-04-01

Efficient reduction of CO2 into useful carbon resources particularly CO is an essential reaction for developing alternate sources of fuels and for reducing the greenhouse effect of CO2. The binuclear Ni, Fe-containing carbon monoxide dehydrogenase (CODHs) efficiently catalyzes the reduction of CO2 to CO. The location of Ni and Fe at proper positions allows their cooperation for CO2 to CO conversion through a push-pull mechanism. Bio-inspired from CODHs, we used several cofacial porphyrin dimers with different substituents as suitable ligands for holding two Fe ions with suitable Fe-Fe separation distance to efficiently and selectively promote CO2 to CO conversion with high turnover frequencies, TOFs. The substituents on the porphyrin rings greatly affect the catalysis process. By introducing electron-withdrawing/-donating groups, e.g. electron-withdrawing perfluorophenyl, at all meso positions of the porphyrin rings, the catalysis overpotential, η was minimized by ≈0.3 V compared to that obtained by introducing electron-donating mesityl groups. The Fe porphyrin dimers among reported catalysts are the most efficient ones for CO2 to CO conversion. Control experiments indicate that the high performance of the current CO2 to CO conversion catalysts is due to the presence of binuclear Fe centers at suitable Fe-Fe separation distance.

Adsorption and Electronic Structure of Sr and Ag Atoms on Graphite Surfaces: a First-Principles Study

NASA Astrophysics Data System (ADS)

Luo, Xiao-Feng; Fang, Chao; Li, Xin; Lai, Wen-Sheng; Sun, Li-Feng; Liang, Tong-Xiang

2013-06-01

The adsorption behaviors of radioactive strontium and silver nuclides on the graphite surface in a high-temperature gas-cooled reactor are studied by first-principles theory using generalized gradient approximation (GGA) and local density approximation (LDA) pseudo-potentials. It turns out that Sr prefers to be absorbed at the hollow of the carbon hexagonal cell by 0.54 eV (GGA), while Ag likes to sit right above the carbon atom with an adsorption energy of almost zero (GGA) and 0.45 eV (LDA). Electronic structure analysis reveals that Sr donates its partial electrons of the 4p and 5s states to the graphite substrate, while Ag on graphite is a physical adsorption without any electron transfer.

Medicare and state health care programs: fraud and abuse; electronic health records safe harbor under the anti-kickback statute. Final rule.

PubMed

2013-12-27

In this final rule, the Office of Inspector General (OIG) amends the safe harbor regulation concerning electronic health records items and services, which defines certain conduct that is protected from liability under the Federal anti-kickback statute, section 1128B(b) of the Social Security Act (the Act). Amendments include updating the provision under which electronic health records software is deemed interoperable; removing the electronic prescribing capability requirement; extending the sunset provision until December 31, 2021; limiting the scope of protected donors to exclude laboratory companies; and clarifying the condition that prohibits a donor from taking any action to limit or restrict the use, compatibility, or interoperability of the donated items or services.

Photodegradation of dibenzoylmethanes: potential cause of photocontact allergy to sunscreens.

PubMed

Karlsson, Isabella; Hillerström, Lisa; Stenfeldt, Anna-Lena; Mårtensson, Jerker; Börje, Anna

2009-11-01

One of the most frequently observed photoallergens today is the sunscreen agent 4-tert-butyl-4'-methoxy dibenzoylmethane (1a). The structurally similar compound, 4-isopropyldibenzoylmethane (1b), was a common cause of sunscreen allergy in the eighties and early nineties but was removed from the market in 1993 and replaced with dibenzoylmethane 1a. We have studied the photodegradation of the dibenzoylmethane 1a, to better understand how these substances cause an immune reaction. Several expected degradation products were formed and identified. Of these, arylglyoxals and benzils were of particular interest because they were unexplored as potential contact allergens. The allergenic potential of photodegraded 1a was evaluated by screening the formed arylglyoxals and benzils for their sensitizing capacity in the murine local lymph node assay. The arylglyoxals were found to be strong sensitizers. They were also found to be highly reactive toward the nucleophile arginine, which indicates that the immunogenic hapten-protein complex could be formed via an electrophilic-nucleophilic pathway. By varying the electron-withdrawing or -donating capacity of the substituent in the para position of the arylglyoxal, the electronic effects were shown to have no significant impact on either the sensitizing or the electrophilic power of arylglyoxals. Thus, a change in the substitution pattern of the parent dibenzoylmethane will not influence the sensitizing capacity of the products formed from them upon photodegradation. Furthermore, the combined studies of benzils, using the local lymph node assay and a cell proliferation assay, indicate that the benzils are cytotoxic rather than allergenic. Taken together, this study presents strong indication that photocontact allergy to dibenzoylmethanes is caused by the arylglyoxals that are formed upon photodegradation.

Role of coherence and delocalization in photo-induced electron transfer at organic interfaces

NASA Astrophysics Data System (ADS)

Abramavicius, V.; Pranculis, V.; Melianas, A.; Inganäs, O.; Gulbinas, V.; Abramavicius, D.

2016-09-01

Photo-induced charge transfer at molecular heterojunctions has gained particular interest due to the development of organic solar cells (OSC) based on blends of electron donating and accepting materials. While charge transfer between donor and acceptor molecules can be described by Marcus theory, additional carrier delocalization and coherent propagation might play the dominant role. Here, we describe ultrafast charge separation at the interface of a conjugated polymer and an aggregate of the fullerene derivative PCBM using the stochastic Schrödinger equation (SSE) and reveal the complex time evolution of electron transfer, mediated by electronic coherence and delocalization. By fitting the model to ultrafast charge separation experiments, we estimate the extent of electron delocalization and establish the transition from coherent electron propagation to incoherent hopping. Our results indicate that even a relatively weak coupling between PCBM molecules is sufficient to facilitate electron delocalization and efficient charge separation at organic interfaces.

Association of mGFR of the Remaining Kidney Divided by Its Volume before Donation with Functional Gain in mGFR among Living Kidney Donors

PubMed Central

Gaillard, François; Tissier, Anne-Marie; Fournier, Catherine; Le Nestour, Alexis; Corréas, Jean-Michel; Slimani-Thevenet, Hind; Martinez, Frank; Léon, Carine; Eladari, Dominique; Timsit, Marc-Olivier; Otal, Philippe; Hignette, Chantal; Friedlander, Gérard; Méjean, Arnaud; Houillier, Pascal; Kamar, Nassim; Legendre, Christophe

2016-01-01

Background and objectives The predictors of long–term renal function in living kidney donors are currently discussed. Our objectives were to describe the predictors of functional gain of the remaining kidney after kidney donation. We hypothesized that GFR of the remaining kidney divided by volume of this kidney (rk-GFR/vol) would reflect the density of functional nephrons and be inversely associated with functional gain of the remaining kidney. Design, setting, participants, & measurements We conducted a prospective monocentric study including 63 living donors (26 men; 50.3±11.8 years old) who had been evaluated for 51Cr-EDTA and measured GFR, split renal function by scintigraphy before donation (between 2004 and 2009), and measured GFR at 5.7±0.5 years after donation. For 52 donors, volume of the remaining kidney (measured and estimated with the ellipsoid formula using renal computed tomography scannography) was determined before donation. We tested our hypothesis in an external validation cohort of 39 living donors (13 men; 51.0±9.4 years old) from another single center during the same time period. Results For the main cohort, the mean measured GFR was 97.6±13.0 ml/min per 1.73 m2 before donation and 63.8±9.4 ml/min per 1.73 m2 at 5 years. Functional gain averaged 16.2±7.2 ml/min per 1.73 m2 (+35.3%±16.7%). Multivariate analysis showed that age, body mass index, and rk-GFR/vol at donation were negatively correlated with functional gain and had strong predictive power of the 5-year functional gain (adjusted 5-year functional gain for age: −0.4 [95% confidence interval (95% CI), −0.5 to −0.1]; body mass index: −0.3 [95% CI, −0.6 to −0.1]; rk-GFR/vol: −55.1 [95% CI, −92.3 to −17.9]). We tested this model in the external validation cohort (adjusted 5-year functional gain for age: −0.1 [95% CI, −0.5 to 0.3]; body mass index: −0.9 [95% CI, −1.8 to −0.1]; rk-GFR/vol: −97.6 [95% CI, −137.5 to −57.6]) and confirmed that rk-GFR/vol was inversely associated with 5-year functional gain. Conclusions For given age and body mass index, the long–term functional gain of the remaining kidney is inversely associated with the new variable rk-GFR/vol at donation. PMID:27189317

Dermatology and pathology arrangements: navigating the compliance risks.

PubMed

Wood, Jane Pine; Cougevan, Bridget; McGovern, Jenny

2013-12-01

Purchased service arrangements, establishing in-house professional pathology services, conducting technical component histology within a dermatology practice, and electronic medical records technology donations are ways that dermatology practices are responding to the current health care delivery and payment changes. This article will provide a general framework for navigating the compliance risks and structure considerations associated with these relationships between dermatologists and pathologists.

Final report to the Department of Energy for Grant DE-FG02-01ER54663

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

McGrath, Robert T.

2001-10-01

Funds provided from the DOE award were used to support student participation in the 54th Gaseous Electronics Conference held at Penn State Unversity October 9-12, 2001. DOE funds were distributed to 27 graduate students, each of whom presented research results at the conference. DOE resources were supplemented by donations from several industrial firms.

High-efficiency tris(8-hydroxyquinoline)aluminum (Alq3) complexes for organic white-light-emitting diodes and solid-state lighting.

PubMed

Pérez-Bolívar, César; Takizawa, Shin-ya; Nishimura, Go; Montes, Victor A; Anzenbacher, Pavel

2011-08-08

Combinations of electron-withdrawing and -donating substituents on the 8-hydroxyquinoline ligand of the tris(8-hydroxyquinoline)aluminum (Alq(3)) complexes allow for control of the HOMO and LUMO energies and the HOMO-LUMO gap responsible for emission from the complexes. Here, we present a systematic study on tuning the emission and electroluminescence (EL) from Alq(3) complexes from the green to blue region. In this study, we explored the combination of electron-donating substituents on C4 and C6. Compounds 1-6 displayed the emission tuning between 478 and 526 nm, and fluorescence quantum yield between 0.15 and 0.57. The compounds 2-6 were used as emitters and hosts in organic light-emitting diodes (OLEDs). The highest OLED external quantum efficiency (EQE) observed was 4.6%, which is among the highest observed for Alq(3) complexes. Also, the compounds 3-5 were used as hosts for red phosphorescent dopants to obtain white light-emitting diodes (WOLED). The WOLEDs displayed high efficiency (EQE up to 19%) and high white color purity (color rendering index (CRI≈85). Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Acquiring High-Performance Deep-Blue OLED Emitters through an Unexpected Blueshift Color-Tuning Effect Induced by Electron-Donating -OMe Substituents.

PubMed

Peng, Song; Zhao, Yihuan; Fu, Caixia; Pu, Xuemei; Zhou, Liang; Huang, Yan; Lu, Zhiyun

2018-06-07

A series of blue-emissive 7-(diphenylamino)-4-phenoxycoumarin derivatives bearing -CF 3 , -OMe, or -N(Me) 2 substituents on the phenoxy subunit were synthesized. Although both the -CF 3 and -N(Me) 2 modifications were found to trigger redshifted fluorescence, the -OMe substitution was demonstrated to exert an unexpected blueshift color-tuning effect toward the deep-blue region. The reason is that the moderate electron-donating -OMe group can endow coumarins with unaltered HOMO but elevated LUMO energy levels. Moreover, the -OMe substitution was found to be beneficial to the thermal stability of these coumarins. Therefore, the trimethoxy-substituted objective compound can act as a high-performance deep-blue organic light-emitting diode (OLED) emitter, and OLED based on it emits deep-blue light with CIE coordinates of (0.148, 0.084), maximum luminance of 7800 cd m -2 , and maximum external quantum efficiency of 5.1 %. These results not only shed light on the molecular design strategy for high-performance deep-blue OLED emitters through color-tuning, but also show the perspective of coumarin derivatives as deep-blue OLED emitters. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Optical basicity and polarizability for copper-zinc doped sol-gel glasses

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

Kaur, G., E-mail: gkapds@gmail.com; Pandey, O. P.; Amjotkaur,, E-mail: amjotkaur93@gmail.com

2016-05-06

CaO-SiO{sub 2}-B{sub 2}O{sub 3}-P{sub 2}O{sub 5} glasses have been studied by varying ratios of Copper oxide and Zinc oxide. Glasses were prepared using Sol-Gel technique. Opitical Basicity and oxide ion Polarizability were calculated and discussed in relation with non bridging Oxygen ions (NBOs). Optical basicity is average electron donating capability of an oxide atom. All glasses had a little difference in optical basicity and polarizability values but CZ8 glass (20CaO-60SiO{sub 2}-5B{sub 2}O{sub 3}-5P{sub 2}O{sub 5}-2CuO-8ZnO) came out to show highest optical basicity and polarizability with value 0.5177 and 0.9798 respectively. This showed the highest electron donating tendency of CZ8 glassmore » and highest number of NBOs. These were minimum for CZ2 glass with 8CuO and 2ZnO. In aspect of optical basicity and polarizability glasses follow the series CZ2 < CZ4 < CZ6 < CZ8. Increasing concentration of ZnO and decreasing concentration of CuO lead to higher optical basicity and oxide ion polarizability.« less

Comparison of reactivity of Pt(II) center in the mononuclear and binuclear organometallic diimineplatinum complexes toward oxidative addition of methyl iodide

NASA Astrophysics Data System (ADS)

Hashemi, Majid

2016-01-01

The reactivities of Pt(II) center in a series of organometallic mononuclear Pt(II), binuclear Pt(II) and binuclear mixed-valence Pt(II)-Pt(IV) complexes toward oxidative addition of MeI have been compared from a theoretical point of view. The nucleophilicity index and electron-donation power were calculated for each of these complexes. The energies of HOMO and dZ2 orbital were determined for these complexes. Very good correlations were found between logk2 (k2 is the experimentally determined second order rate constant for the oxidative addition of MeI on these complexes) and nucleophilicity index or electron-donation power for these complexes. The correlation between logk2 and the energy of HOMO or the energy of dZ2 orbital were also very good. The condensed-to-atom Fukui functions for electrophilic attack on these complexes showed that the Pt(II) center is the preferred site for the oxidative addition of MeI. All of these observations are in agreement with the proposed SN2 type mechanism in the oxidative addition of MeI on the Pt(II) center in these complexes.

Social support attenuates presyncopal reactions to blood donation.

PubMed

Hanson, Sarah A; France, Christopher R

2009-05-01

The experience of unpleasant blood donation reactions (e.g., dizziness, nausea, and fainting) has been linked to negative attitudes about donation and decreased likelihood of repeat donation. Consequently, interventions to reduce the adverse effects of blood donation are important and likely to increase donor retention. Based on laboratory studies suggesting that social support attenuates both physical and psychological responses to stress, the present study hypothesized that the presence of a supportive person during the donation process may help reduce reactions. A final sample of 65 men and women with fewer than three prior donations was randomly assigned to either donate blood as usual or donate with a supportive research assistant. Donors in the support condition were accompanied throughout the donation process by a female research assistant who provided encouragement, made reassuring remarks, and engaged in small talk. Donors in both conditions completed a series of questions to assess anxiety, experience of prefaint reactions, and willingness to provide a future donation. Compared to standard donation controls, donors in the social support condition reported fewer prefaint reactions (F(1,61) = 9.15, p = 0.004, eta(2)= 0.13) and greater likelihood of donating again within the next year (Z =-1.70, p < 0.05, one-tailed). Relatively novice donors report reduced reactions to blood donation when accompanied by a supportive individual, suggesting that social support may be a simple strategy to enhance the donation experience and possibly increase donor retention.

Outcomes of pregnancies achieved by double gamete donation: A comparison with pregnancies obtained by oocyte donation alone.

PubMed

Preaubert, Lise; Vincent-Rohfritsch, Aurélie; Santulli, Pietro; Gayet, Vanessa; Goffinet, François; Le Ray, Camille

2018-03-01

Women increasingly resort to oocyte donation to become pregnant. The high risk of preeclampsia found in oocyte donation pregnancies and the separate risk of preeclampsia associated with sperm donation may be cumulative in double donation pregnancies. We aimed to study the obstetrical and perinatal outcomes of pregnancies obtained by double donation (both oocyte and sperm) in comparison with those obtained by oocyte donation alone (oocyte donation and partner's sperm). This cohort study included all women aged 43 and older who became pregnant after oocyte donation and gave birth between 2010 and 2016 in a tertiary maternity center. Primary outcomes were preeclampsia and hypertensive gestational disorders. Secondary outcomes were gestational diabetes, placental abnormalities, postpartum hemorrhage, perinatal death, and preterm delivery. We used univariate and multivariate analysis to compare IVF with double donation and IVF with oocyte donation alone for obstetric and perinatal outcomes. 247 women, 53 with double donations and 194 with oocyte donations alone, gave birth to 339 children. We observed no significant differences between groups for any obstetric or perinatal complications, except for the risk of gestational diabetes, which was more frequent in women with double donations compared with oocyte donation alone (26.4% vs. 12.9%, P = 0.02) and remained significant after adjustment (aOR = 2.80 95%CI[1.26-6.17]). Rates of gestational hypertension and preeclampsia were high, but similar between groups (20.7% vs. 26.3%, P = 0.41, and 18.9% vs. 17.5%, P = 0.82). Women undergoing oocyte donation should be fully informed of its high rates of obstetric and perinatal risks. However, except for a higher observed risk of gestational diabetes, double donation does not appear to be associated with a higher risk of complications than oocyte donation alone. Copyright © 2017 Elsevier B.V. All rights reserved.

41 CFR 102-37.30 - When does property become available for donation?

Code of Federal Regulations, 2010 CFR

2010-07-01

... become available for donation? 102-37.30 Section 102-37.30 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.30 When does property become available for donation? Excess personal property becomes available for donation the day...

41 CFR 102-37.30 - When does property become available for donation?

Code of Federal Regulations, 2012 CFR

2012-01-01

... become available for donation? 102-37.30 Section 102-37.30 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.30 When does property become available for donation? Excess personal property becomes available for donation the day...

41 CFR 102-37.30 - When does property become available for donation?

Code of Federal Regulations, 2011 CFR

2011-01-01

... become available for donation? 102-37.30 Section 102-37.30 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.30 When does property become available for donation? Excess personal property becomes available for donation the day...

41 CFR 102-37.30 - When does property become available for donation?

Code of Federal Regulations, 2014 CFR

2014-01-01

... become available for donation? 102-37.30 Section 102-37.30 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.30 When does property become available for donation? Excess personal property becomes available for donation the day...

41 CFR 102-37.30 - When does property become available for donation?

Code of Federal Regulations, 2013 CFR

2013-07-01

... become available for donation? 102-37.30 Section 102-37.30 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.30 When does property become available for donation? Excess personal property becomes available for donation the day...

Application of implicit attitude measures to the blood donation context.

PubMed

Warfel, Regina M; France, Christopher R; France, Janis L

2012-02-01

Past blood donation research has relied on explicit (self-report) measures to understand blood donation motivations, but has not yet considered the inherent implicit or automatic processing involved in decision-making. This study addresses this limitation by introducing and validating two novel implicit measures of blood donation attitudes. Healthy young adults (n = 253) performed both image and word versions of a Single Target Implicit Association Test (ST-IAT) and then completed self-report measures of blood donation attitudes, blood and needle fears, social desirability, and donation intention. These results affirmed the validity of the blood donation ST-IATs in at least three ways. First, as expected, nondonors demonstrated more negative implicit donation attitudes than donors. Second, the implicit measures were significantly related in expected directions with explicit measures of donation attitudes as well as blood and needle fears. Finally, implicit donation attitudes were significantly related to donation intention, and the Image ST-IAT (but not the Word ST-IAT) significantly enhanced prediction of donation intention over and above needle fears and marginally enhanced prediction over and above blood fears. Image and word versions of the blood donation ST-IAT offer a valid method of assessing underlying automatic attitudes toward blood donation. © 2012 American Association of Blood Banks.

Pre-donation cognitions of potential living organ donors: the development of the Donation Cognition Instrument in potential kidney donors.

PubMed

Wirken, Lieke; van Middendorp, Henriët; Hooghof, Christina W; Sanders, Jan-Stephan F; Dam, Ruth E; van der Pant, Karlijn A M I; Berendsen, Elsbeth C M; Wellink, Hiske; Dackus, Henricus J A; Hoitsma, Andries J; Hilbrands, Luuk B; Evers, Andrea W M

2017-03-01

Cognitions surrounding living organ donation, including the motivation to donate, expectations of donation and worries about donation, are relevant themes during living donor evaluation. However, there is no reliable psychometric instrument assessing all these different cognitions. This study developed and validated a questionnaire to assess pre-donation motivations, expectations and worries regarding donation, entitled the Donation Cognition Instrument (DCI). Psychometric properties of the DCI were examined using exploratory factor analysis for scale structure and associations with validated questionnaires for construct validity assessment. From seven Dutch transplantation centres, 719 potential living kidney donors were included. The DCI distinguishes cognitions about donor benefits, recipient benefits, idealistic incentives, gratitude and worries about donation (Cronbach's alpha 0.76-0.81). Scores on pre-donation cognitions differed with regard to gender, age, marital status, religion and donation type. With regard to construct validity, the DCI was moderately correlated with expectations regarding donor's personal well-being and slightly to moderately to health-related quality of life. The DCI is found to be a reliable instrument assessing cognitions surrounding living organ donation, which might add to pre-donation quality of life measures in facilitating psychosocial donor evaluation by healthcare professionals. © The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Blood management and transfusion strategies in 600 patients undergoing total joint arthroplasty: an analysis of pre-operative autologous blood donation.

PubMed

Perazzo, Paolo; Viganò, Marco; De Girolamo, Laura; Verde, Francesco; Vinci, Anna; Banfi, Giuseppe; Romagnoli, Sergio

2013-07-01

Blood loss during total joint arthroplasty strongly influences the time to recover after surgery and the quality of the recovery. Blood conservation strategies such as pre-operative autologous blood donation and post-operative cell salvage are intended to avoid allogeneic blood transfusions and their associated risks. Although widely investigated, the real effectiveness of these alternative transfusion practices remains controversial. The surgery reports of 600 patients undergoing total joint arthroplasty (312 hip and 288 knee replacements) were retrospectively reviewed to assess transfusion needs and related blood management at our institute. Evaluation parameters included post-operative blood loss, haemoglobin concentration measured at different time points, ASA score, and blood transfusion strategies. Autologous blood donation increased the odds of receiving a red blood cell transfusion. Reinfusion by a cell salvage system of post-operative shed blood was found to limit adverse effects in cases of severe post-operative blood loss. The peri-operative net decrease in haemoglobin concentration was higher in patients who had predeposited autologous blood than in those who had not. The strengths of this study are the high number of cases and the standardised procedures, all operations having been performed by a single orthopaedic surgeon and a single anaesthesiologist. Our data suggest that a pre-operative autologous donation programme may often be useless, if not harmful. Conversely, the use of a cell salvage system may be effective in reducing the impact of blood transfusion on a patient's physiological status. Basal haemoglobin concentration emerged as a useful indicator of transfusion probability in total joint replacement procedures.

What weighs more-low compliance with self-deferral or minor medical procedures? Explaining the high rate of hepatitis C virus window-period donations in Poland.

PubMed

Czerwinski, Michal; Grabarczyk, Piotr; Stepien, Malgorzata; Kubicka-Russel, Dorota; Tkaczuk, Katarzyna; Brojer, Ewa; Rosinska, Magdalena

2017-08-01

Since the introduction of nucleic acid testing (NAT) for routine blood donor screening, hepatitis C virus (HCV) RNA-only detection rates reported from Poland have been higher than in most other European countries. To examine factors that likely contribute to these window-period donations, we conducted a case-control study among 47 recently HCV-infected blood donors (cases), who gave blood between July 2002 and June 2014, and 141 controls matched by age, sex, and donation dates. Firth-corrected, conditional logistic regression models were fitted to estimate adjusted odds ratios and 95% confidence intervals. Adjusted population-attributable fractions were calculated based on the distribution of exposure among the cases. On multivariate analysis, recent exposures in health care environments not routinely ascertained through predonation questionnaires were strongly associated with recently acquired HCV infection. These exposures included minor medical and dental procedures in the preceding 6 months (adjusted odds ratio, 5.77; 95 % confidence interval, 2.01-18.53). However, based on the population-attributable fraction, more important were behavioral deferrable risks that went unreported at the time of donation, such as high-risk sexual behaviors in the preceding 6 months (population-attributable fraction, 34%) or lifetime histories of drug use (population-attributable fraction, 28%). This study raises questions about the effectiveness of deferral policy in excluding high-risk individuals. In addition, it provides further evidence supporting short, temporal deferrals for small medical procedures and dental treatments in Poland. © 2017 AABB.

Controlling the Conformational Energy of a Phenyl Group by Tuning the Strength of a Nonclassical CH···O Hydrogen Bond: The Case of 5-Phenyl-1,3-dioxane.

PubMed

Bailey, William F; Lambert, Kyle M; Stempel, Zachary D; Wiberg, Kenneth B; Mercado, Brandon Q

2016-12-16

Anancomeric 5-phenyl-1,3-dioxanes provide a unique opportunity to study factors that control conformation. Whereas one might expect an axial phenyl group at C(5) of 1,3-dioxane to adopt a conformation similar to that in axial phenylcyclohexane, a series of studies including X-ray crystallography, NOE measurements, and DFT calculations demonstrate that the phenyl prefers to lie over the dioxane ring in order to position an ortho-hydrogen to participate in a stabilizing, nonclassical CH···O hydrogen bond with a ring oxygen of the dioxane. Acid-catalyzed equilibration of a series of anancomeric 2-tert-butyl-5-aryl-1,3-dioxane isomers demonstrates that remote substituents on the phenyl ring affect the conformational energy of a 5-aryl-1,3-dioxane: electron-withdrawing substituents decrease the conformational energy of the aryl group, while electron-donating substituents increase the conformational energy of the group. This effect is correlated in a very linear way to Hammett substituent parameters. In short, the strength of the CH···O hydrogen bond may be tuned in a predictable way in response to the electron-withdrawing or electron-donating ability of substituents positioned remotely on the aryl ring. This effect may be profound: a 3,5-bis-CF 3 phenyl group at C(5) in 1,3-dioxane displays a pronounced preference for the axial orientation. The results are relevant to broader conformational issues involving heterocyclic systems bearing aryl substituents.

Conversion and origin of normal and abnormal temperature dependences of kinetic isotope effect in hydride transfer reactions.

PubMed

Zhu, Xiao-Qing; Li, Xiu-Tao; Han, Su-Hui; Mei, Lian-Rui

2012-05-18

The effects of substituents on the temperature dependences of kinetic isotope effect (KIE) for the reactions of the hydride transfer from the substituted 5-methyl-6-phenyl-5,6-dihydrophenanthridine (G-PDH) to thioxanthylium (TX(+)) in acetonitrile were examined, and the results show that the temperature dependences of KIE for the hydride transfer reactions can be converted by adjusting the nature of the substituents in the molecule of the hydride donor. In general, electron-withdrawing groups can make the KIE to have normal temperature dependence, but electron-donating groups can make the KIE to have abnormal temperature dependence. Thermodynamic analysis on the possible pathways of the hydride transfer from G-PDH to TX(+) in acetonitrile suggests that the transfers of the hydride anion in the reactions are all carried out by the concerted one-step mechanism whether the substituent is an electron-withdrawing group or an electron-donating group. But the examination of Hammett-type free energy analysis on the hydride transfer reactions supports that the concerted one-step hydride transfer is not due to an elementary chemical reaction. The experimental values of KIE at different temperatures for the hydride transfer reactions were modeled by using a kinetic equation formed according to a multistage mechanism of the hydride transfer including a returnable charge-transfer complex as the reaction intermediate; the real mechanism of the hydride transfer and the root that why the temperature dependences of KIE can be converted as the nature of the substituents are changed were discovered.

Effects of shape, size, and pyrene doping on electronic properties of graphene nanoflakes.

PubMed

Kuamit, Thanawit; Ratanasak, Manussada; Rungnim, Chompoonut; Parasuk, Vudhichai

2017-11-25

Effects of size, shape, and pyrene doping on electronic properties of graphene nanoflakes (GNFs) were theoretically investigated using density functional theory method with PBE, B3PW91, and M06-2X functionals and cc-pVDZ basis set. Two shapes of zigzag GNFs, hexagonal (HGN) and rhomboidal (RGN), were considered. The energy band gap of GNF depends on shape and decreases with size. The HGN has larger band gap energy (1.23-3.96 eV) than the RGN (0.13-2.12 eV). The doping of pyrene and pyrene derivatives on both HGN and RGN was also studied. The adsorption energy of pyrene and pyrene derivatives on GNF does not depend on the shape of GNFs with energies between 21 and 27 kcal mol -1 . The substituent on pyrene enhances the binding to GNF but the strength does not depend on electron withdrawing or donating capability. The doping by pyrene and pyrene derivatives also shifts the HOMO and LUMO energies of GNFs. Both positive (destabilizing) and negative (stabilizing) shifts on HOMO and LUMO of GNFs were seen. The direction and magnitude of the shift do not follow the electron withdrawing and donating capability of pyrene substituents. However, only a slight shift was observed for doped RGN. A shift of 0.19 eV was noticed for HOMO of HGN doped with 1-aminopyrene (pyNH 2 ) and of 0.04 eV for LUMO of HGN doped with 1-pyrenecarboxylic acid (pyCOOH). Graphical Abstract HOMO and LUMO Energies of pyrene/pyrene derivatives doped Graphene Nanoflakes.

Knowledge, Attitudes, Practices, and Factors Associated with Voluntary Blood Donation among University Students in Kilimanjaro, Tanzania

PubMed Central

Elias, Elionora; Philemon, Rune N.; Damian, Damian J.; Msuya, Sia E.

2016-01-01

Background. Understanding the knowledge and awareness of blood donation among potential blood donors in the population, like young people, and the associated attitudes and practices is important. Methodology. This was a cross-sectional study whereby a self-administered questionnaire was used to collect information from the consenting participants. Results. A total of 422 participants were enrolled. Their mean age was 24.2 (SD 3.6) years. Of the 422, 30% have ever donated blood. 55% of those who had ever donated were repeated blood donors. Majority of the participants (93%) had positive attitudes towards blood donation and 88% were willing to donate in the future. Factors that were significantly associated with ever donating blood were male gender, knowing a person who has donated blood, knowledge of the amount of blood donated, willingness to donate in the future, and not expecting any postdonation reward. Discussion. High awareness, positive attitude, and high intention to donate in the future should be used to underscore the need to educate the young people on the value of blood donation in saving lives and to give them correct information on overall requirements for blood donation. PMID:28070449

Knowledge, Attitudes, Practices, and Factors Associated with Voluntary Blood Donation among University Students in Kilimanjaro, Tanzania.

PubMed

Elias, Elionora; Mauka, Wilhellmuss; Philemon, Rune N; Damian, Damian J; Mahande, Michael J; Msuya, Sia E

2016-01-01

Background . Understanding the knowledge and awareness of blood donation among potential blood donors in the population, like young people, and the associated attitudes and practices is important. Methodology . This was a cross-sectional study whereby a self-administered questionnaire was used to collect information from the consenting participants. Results . A total of 422 participants were enrolled. Their mean age was 24.2 (SD 3.6) years. Of the 422, 30% have ever donated blood. 55% of those who had ever donated were repeated blood donors. Majority of the participants (93%) had positive attitudes towards blood donation and 88% were willing to donate in the future. Factors that were significantly associated with ever donating blood were male gender, knowing a person who has donated blood, knowledge of the amount of blood donated, willingness to donate in the future, and not expecting any postdonation reward. Discussion . High awareness, positive attitude, and high intention to donate in the future should be used to underscore the need to educate the young people on the value of blood donation in saving lives and to give them correct information on overall requirements for blood donation.

Eye donation - awareness and willingness among attendants of patients at various clinics in Melaka, Malaysia.

PubMed

Bhandary, Sulatha; Khanna, Rajesh; Rao, Krishna A; Rao, Lavanya G; Lingam, Kamala D; Binu, V

2011-01-01

Corneal blindness accounts for 3.42% of blindness in Malaysia; the rate of eye donation is low. The aim of the study was to assess the awareness about eye donation and willingness to donate eyes among attendants of patients at various clinics in Melaka, Malaysia. This observational study was conducted on attendants who accompanied patients (n = 400) visiting various outpatient departments of the General Hospital and two peripheral clinics in Melaka between August and October 2007. The participants answered a questionnaire (Malay and English versions) which included demographic profile, awareness of eye donation, knowledge regarding facts of eye donation, and willingness to donate eyes. Univariate and multivariate logistic regression was performed at 5% level of significance. Awareness of eye donation was observed in 276 (69%) participants. Multivariate analysis showed that awareness was more among females when compared to males (P = 0.009). Of the 276 participants who were aware of eye donation, only 34.42% were willing to donate eyes. Willingness was more among the Indian race (P = 0.02) and males (P = 0.02). Educational status did not influence the willingness to donate eyes. Although majority of participants were aware of eye donation, willingness to donate eyes was poor.

Impact Factors and Attitudes Toward Organ Donation Among Transplantation Patients and Their Caregivers in China.

PubMed

Zhang, Q-X; Xie, J-F; Zhou, J-D; Xiao, S-S; Liu, A-Z; Hu, G-Q; Chen, Y; Wang, C-Y

2017-11-01

This study's purpose was to investigate the attitudes toward organ donation among renal transplantation patients and their caregivers. In addition, we sought to explore the impact factors that affect their attitudes toward deceased organ donation. A self-administrated questionnaire was used, which consisted of two parts: 1) demographic data, and 2) transplantation and donation-related data. This study was conducted in three transplantation follow-up centers in three hospitals using a cross-sectional approach. SPSS 17.0 software was used to analysis descriptive and inferential statistics for data. The responses were analyzed using descriptive statistics and logistic regression analysis. We received 426 effective questionnaires. The renal transplantation patients' mean age was 40.84 years. Among these patients, 67.8% were willing to accept the organ transplantation surgery for their relatives, 67.4% were willing to donate a living kidney to a close relative, 62.7% were willing to donate organs after death, 53.5% were willing to register in the national organ donation system, and 51.4% were willing to sign the organ donation consent when facing their relatives becoming a potential organ donor. Age, marriage status, education level, understanding of transplantation procedures and understanding of donation procedures had statistical significance in the difference of the attitudes toward donate their organs after death (P < .05). Renal transplantation patients in our study are more willing to donate organs after death than their caregivers, but both their attitudes toward deceased donation were not very optimistic. There is a significant relationship between participants' willingness and knowledge of organ donation; patients with more understanding of the transplantation and donation procedure were more willing to donate organs after death. Affected by traditional values such as Confucianism, many people still cannot accept registering in the national organ donation system or sign the organ donation consent when facing their relatives becoming potential organ donors. There is a need to give adequate training regarding donation to increase donation rates. The government must provide education from the perspective of scientific knowledge to change the traditional views of the public, which may then increase the donation rate in China. Copyright © 2017 Elsevier Inc. All rights reserved.

Exploring opinions and beliefs about cord blood donation among Hispanic and non-Hispanic black women.

PubMed

Rucinski, Dianne; Jones, Risé; Reyes, Brenda; Tidwell, Lawon; Phillips, RoiAnn; Delves, Denise

2010-05-01

Despite higher birth rates among non-Hispanic blacks and Hispanics, the availability of umbilical cord blood from these groups is lower due to lower donation rates than that of non-Hispanic whites. Similar racial and ethnic disparities in donation rates have been found for blood and organ donation. This study is among the first to explore beliefs and attitudes toward umbilical cord blood donation among Hispanic and non-Hispanic black women. Five focus groups composed of Hispanic and non-Hispanic black women were conducted to explore how women conceptualize information needs about umbilical cord blood donation and from whom women want to receive information about donation. Participants were adult women who had given birth within the past year or were pregnant. Lack of basic information regarding umbilical cord blood, its harvesting and use, and the steps and conditions necessary to donate were primary barriers to donation. Women expressed confusion over the differences between "donation" and "banking." The social value of donation was explicitly weighed in terms of the cost of the donation effort. Doctors were viewed as critical sources for information about donation, although women expressed skepticism about doctors' ability to convey sufficient information during short office visits. Efforts to increase donation rates among Hispanic and non-Hispanic black women should include information about both the technical aspects and the social value of donation. The specific terms "umbilical" and "donation" should be used consistently to prevent misunderstanding. Information should be provided by physicians with follow-up by other health providers.

The marriage of peripherally metallated and directly linked porphyrins: bromidobis(phosphine)platinum(II) as a cation-stabilizing substituent on directly linked and fused triply linked diporphyrins.

PubMed

Hartnell, Regan D; Yoneda, Tomoki; Mori, Hirotaka; Osuka, Atsuhiro; Arnold, Dennis P

2013-11-01

A meso-bromidoplatiniobis(triphenylphosphine) η(1)-organometallic porphyrin monomer was prepared by the oxidative addition of meso-bromoZnDPP (DPP=dianion of 5,15-diphenylporphyrin) to a platinum(0) species. The meso-meso directly linked dimeric porphyrin (5) was prepared from this monomer by silver(I)-promoted oxidative coupling and planarized to give a triply linked dizinc(II) porphyrin dimer (8). Acidic demetallation of 8 afforded the bis(free base) 9. Dimer 5 was demetallated then remetallated with nickel(II) to give the dinickel(II) analogue 10, the X-ray crystal structure of which showed a twisted molecule with ruffled, orthogonal NiDPP rings, terminated by square-planar trans-[Pt(PPh3)2Br] units. New compounds were fully characterized spectroscopically, and the fused diporphyrin exhibited a broad, low-energy, near-IR electronic absorption band near 1100 nm. Electrochemical measurements of this series indicate that the organometallic fragment is a strong electron donor towards the porphyrin ring. The triply linked organometallic diporphyrin has a substantially lowered first one-electron oxidation potential (-0.35 V versus the ferrocene/ferrocenium couple (Fc/Fc(+))) and a narrow HOMO-LUMO gap of 0.96 V. Solutions prepared for NMR spectroscopy slowly decompose with degradation of the signals, which is attributed to partial oxidation to the cation radical. This paramagnetic species can be reduced in situ by hydrazine to restore the NMR spectrum to its former appearance. The combined influence of the two [Pt(PPh3)2Br] electron-donating substituents is sufficient to make dimer too aerobically unstable to allow further elaboration. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

41 CFR 102-37.35 - Who handles the donation of surplus property?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Who handles the donation...-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.35 Who handles the donation of surplus property? (a) The SASPs handle the donation of most surplus property to eligible donees...

41 CFR 102-37.45 - How long is property available for donation screening?

Code of Federal Regulations, 2010 CFR

2010-07-01

... available for donation screening? 102-37.45 Section 102-37.45 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.45 How long is property available for donation screening? Entities authorized to participate in the donation program may...

41 CFR 102-37.45 - How long is property available for donation screening?

Code of Federal Regulations, 2011 CFR

2011-01-01

... available for donation screening? 102-37.45 Section 102-37.45 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.45 How long is property available for donation screening? Entities authorized to participate in the donation program may...

41 CFR 102-37.45 - How long is property available for donation screening?

Code of Federal Regulations, 2013 CFR

2013-07-01

... available for donation screening? 102-37.45 Section 102-37.45 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.45 How long is property available for donation screening? Entities authorized to participate in the donation program may...

41 CFR 102-37.35 - Who handles the donation of surplus property?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Who handles the donation...-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.35 Who handles the donation of surplus property? (a) The SASPs handle the donation of most surplus property to eligible donees...

41 CFR 102-37.35 - Who handles the donation of surplus property?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Who handles the donation...-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.35 Who handles the donation of surplus property? (a) The SASPs handle the donation of most surplus property to eligible donees...

41 CFR 102-37.35 - Who handles the donation of surplus property?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Who handles the donation...-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.35 Who handles the donation of surplus property? (a) The SASPs handle the donation of most surplus property to eligible donees...

41 CFR 102-37.35 - Who handles the donation of surplus property?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Who handles the donation...-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.35 Who handles the donation of surplus property? (a) The SASPs handle the donation of most surplus property to eligible donees...

41 CFR 102-37.45 - How long is property available for donation screening?

Code of Federal Regulations, 2014 CFR

2014-01-01

... available for donation screening? 102-37.45 Section 102-37.45 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.45 How long is property available for donation screening? Entities authorized to participate in the donation program may...

41 CFR 102-37.45 - How long is property available for donation screening?

Code of Federal Regulations, 2012 CFR

2012-01-01

... available for donation screening? 102-37.45 Section 102-37.45 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY General Provisions Donation Overview § 102-37.45 How long is property available for donation screening? Entities authorized to participate in the donation program may...

Achievements and barriers in the organ donation process: a critical analysis of donation coordinators' discourse.

PubMed

Mercado-Martínez, Francisco J; Díaz-Medina, Blanca A; Hernández-Ibarra, Eduardo

2013-09-01

Donation coordinators play an important role in the success or failure of organ donation and transplant programs. Nevertheless, these professionals' perspectives and practices have hardly been explored, particularly in low- and middle-income countries. To examine donation coordinators' discourse on the organ donation process and the barriers they perceive. A critical qualitative study was carried out in Guadalajara, Mexico. Twelve donation coordinators from public and private hospitals participated. DATA GATHERING AND ANALYSIS: Data were gathered by using semistructured interviews and critical discourse analysis. Participants indicated that partial results have been achieved in deceased organ donation. Concomitantly, multiple obstacles have adversely affected the process and outcomes: at the structural level, the fragmentation of the health system and the scarcity of financial and material resources; at the relational level, nonegalitarian relationships between coordinators and hospital personnel; at the ideational level, the transplant domain and its specialists overshadow the donation domain and its coordinators. Negative images are associated with donation coordinators. Organ donation faces structural, relational, and ideational barriers; hence, complex interventions should be undertaken. Donation coordinators also should be recognized by the health system.

Interfacial Charge Transfer States in Condensed Phase Systems

NASA Astrophysics Data System (ADS)

Vandewal, Koen

2016-05-01

Intermolecular charge transfer (CT) states at the interface between electron-donating (D) and electron-accepting (A) materials in organic thin films are characterized by absorption and emission bands within the optical gap of the interfacing materials. CT states efficiently generate charge carriers for some D-A combinations, and others show high fluorescence quantum efficiencies. These properties are exploited in organic solar cells, photodetectors, and light-emitting diodes. This review summarizes experimental and theoretical work on the electronic structure and interfacial energy landscape at condensed matter D-A interfaces. Recent findings on photogeneration and recombination of free charge carriers via CT states are discussed, and relations between CT state properties and optoelectronic device parameters are clarified.

Blood Donation Process

MedlinePlus

... to donate. All medical equipment used for this test, as well as during the donation process, is sterile, used only once and then disposed. Blood Donation Once the pre-donation screening is finished, you will proceed to ...

A cost-effectiveness comparison of embryo donation with oocyte donation.

PubMed

Finger, Reginald; Sommerfelt, Carol; Freeman, Melanie; Wilson, Carrie K; Wade, Amy; Daly, Douglas

2010-02-01

To compare the cost-effectiveness of embryo donation (ED) to that of oocyte donation (OD). Calculation of cost-effectiveness ratios (costs per outcome achieved) using data derived from clinical practices. In vitro fertilization centers and embryo donation programs. Infertile couples undergoing oocyte donation or embryo donation. Oocyte donation or embryo donation cycles. Cost-effectiveness ratios. For a single cycle, ED is approximately twice as cost-effective as OD, with a cost-effectiveness ratio of $21,990 per live delivery compared to 40,600 dollars. When strategies of up to three cycles (to achieve one live delivery) are used, ED costs 13,505 dollars per live delivery compared to 31,349 dollars for OD. Cost-effectiveness is a compelling reason for infertile couples to consider embryo donation. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Right here, right now: the impact of the blood donation context on anxiety, attitudes, subjective norms, self-efficacy, and intention to donate blood.

PubMed

Clowes, Rebekah; Masser, Barbara M

2012-07-01

While research has established the role of anticipated emotions in augmented Theory of Planned Behavior (TPB) models of donor behavior, research has yet to consider the impact of immediate emotions that may be triggered by the blood donor context on respondents' intentions to donate blood. This study explored the impact of blood donor paraphernalia on respondents' positivity toward blood donation and on the interrelationships typically observed in TPB blood donation studies. Seventy-six participants were randomly allocated to complete TPB questionnaires assessing attitudes, subjective norm, and self-efficacy along with intention to donate blood in either an affectively "hot" (blood donation paraphernalia) or a cold (control) condition. Anxiety about donating blood was also assessed. Respondents in the affectively hot condition reported significantly greater anxiety about donating blood along with less positive attitudes, weaker subjective norms, lower self-efficacy, and lower intention to donate than respondents in the cold control condition. In support of extant TPB research, correlational analyses indicated that the relationships between attitudes, self-efficacy, and intention were not impacted upon by condition. Blood donation paraphernalia induces anxiety in donors and results in diminished positivity toward donating. An awareness of what donors experience as a function of the context of blood donation may allow blood services to effectively intervene to bolster donors' positivity toward blood donation at the point where donation can take place. © 2011 American Association of Blood Banks.

Effects of phased education on attitudes toward organ donation and willingness to donate after brain death in an Asian country.

PubMed

Park, Ui Jun; Han, Sang Youb; Han, Kum Hyun; Oh, Se Won; Jang, Hye-Yeon; Kim, Hyoung Tae; Roh, Young-Nam

2018-05-23

This study aims to investigate the effects of phased education on attitudes toward organ donation and willingness to donate after brain death. A survey was conducted using a questionnaire to examine attitudes toward organ donation of the families of patients admitted to a surgical intensive care unit (SICU) between March 1, 2014 and September 30, 2016. Ninety-two people voluntarily participated in this survey. Before reviewing the educational material, 75.0% had a positive attitude toward organ donation, 60.9% were willing to donate their own organs, and 38.0% were willing to donate a family member's organs. After reviewing the educational material, these figures increased to 92.4%, 80.4%, and 56.5%, respectively. Before receiving an education, there was a significant difference in consistency between people's attitudes and willingness to donate their own organs, versus donating a family member's organs (79.3% vs 54.3%, p < 0.001). With phased education, these percentages increased from 79.3% to 85.9% with regard to donating one's own organs, and from 54.3% to 64.1% with regard to donating a family member's organs. Phased education was effective overall, but it had a limited effect on changing the willingness to donate a family member's organs. It increased the consistency between people's attitudes toward organ donation and willingness to donate their own, or a family member's organs. Copyright © 2018. Published by Elsevier Taiwan.

Body donation in India: social awareness, willingness, and associated factors.

PubMed

Rokade, Shrikant A; Gaikawad, Anjana P

2012-01-01

With the attendant rise of the number of medical colleges in India over past few decades, the demand for cadavers used in medical education and research is growing. However, there is an insufficient supply of donated cadavers available for dissection. This study was undertaken to assess the general population's awareness of body donation programs and willingness to donate in the State of Maharashtra, India. The willingness of participants to donate was compared with age, gender, and education of the respondents. A total of 625 adult individuals from the State of Maharashtra participated in a survey composed of questions about age, sex, education, awareness of body donation programs, and willingness to donate. It was found that 90.9% of the medical colleges surveyed reported an inadequate supply of cadavers. Of the general population, 32.1% of respondents were aware of body donation, compared to 95.83% of health care professionals. However, only 19.5% of the general population and 44.9% of health care professionals were willing to donate their bodies for anatomical education. Younger age groups, males, graduates, and postgraduates were found more willing to donate their bodies. Organ donation was preferred over body donation. A lack of awareness about body donation was the main factor responsible for respondents' "no body donation" response in the general population, along with firm religious beliefs and customs, the fear that the donated body will not be treated with respect and dignity, and the unacceptability of the dissection of one's own body. To overcome the current shortage of donated cadavers, efforts should be undertaken to change the mindset of the wider Indian society toward body donation. The authors believe this is possible through awareness campaigns and that prospective donors' concerns should be addressed appropriately. Proper guidance and assistance regarding body donation should be easily available for potential donors. Copyright © 2012 American Association of Anatomists.

Pediatric Donation After Circulatory Determination of Death: A Scoping Review.

PubMed

Weiss, Matthew J; Hornby, Laura; Witteman, William; Shemie, Sam D

2016-03-01

Although pediatric donation after circulatory determination of death is increasing in frequency, there are no national or international donation after circulatory determination of death guidelines specific to pediatrics. This scoping review was performed to map the pediatric donation after circulatory determination of death literature, identify pediatric donation after circulatory determination of death knowledge gaps, and inform the development of national or regional pediatric donation after circulatory determination of death guidelines. Terms related to pediatric donation after circulatory determination of death were searched in Embase and MEDLINE, as well as the non-MEDLINE sources in PubMed from 1980 to May 2014. Seven thousand five hundred ninety-seven references were discovered and 85 retained for analysis. All references addressing pediatric donation after circulatory determination of death were considered. Exclusion criteria were articles that did not address pediatric patients, animal or laboratory studies, surgical techniques, and local pediatric donation after circulatory determination of death protocols. Narrative reviews and opinion articles were the most frequently discovered reference (25/85) and the few discovered studies were observational or qualitative and almost exclusively retrospective. Retained references were divided into themes and analyzed using qualitative methodology. The main discovered themes were 1) studies estimating the number of potential pediatric donation after circulatory determination of death donors and their impact on donation; 2) ethical issues in pediatric donation after circulatory determination of death; 3) physiology of the dying process after withdrawal of life-sustaining therapy; 4) cardiac pediatric donation after circulatory determination of death; and 5) neonatal pediatric donation after circulatory determination of death. Donor estimates suggest that pediatric donation after circulatory determination of death will remain an event less common than brain death, albeit with the potential to substantially expand the existing organ donation pool. Limited data suggest outcomes comparable with organs donated after neurologic determination of death. Although there is continued debate around ethical aspects of pediatric donation after circulatory determination of death, all pediatric donation after circulatory determination of death publications from professional societies contend that pediatric donation after circulatory determination of death can be practiced ethically. This review provides a comprehensive overview of the published literature related to pediatric donation after circulatory determination of death. In addition to informing the development of pediatric-specific guidelines, this review serves to highlight several important knowledge gaps in this topic.

"Why throw away something useful?": Attitudes and opinions of people treated for bipolar disorder and their relatives on organ and tissue donation.

PubMed

Padoan, Carolina S; Garcia, Lucas F; Rodrigues, Aline A; Patusco, Lucas M; Atz, Mariana V; Kapczinski, Flavio; Goldim, José R; Magalhães, Pedro V S

2017-03-01

In regard to mental illness, brain donation is essential for the biological investigation of central pathology. Nevertheless, little is known about the thoughts of people with mental disorders on tissue donation for research. Here, our objective was to understand the attitudes and opinions of people treated for bipolar disorder and their relatives regarding donation in general, and particularly donation for research. This is a qualitative study that used in-depth interviews to determine the thoughts of participants regarding tissue donation for research. Theoretical sampling was used as a recruitment method. Grounded theory was used as a framework for content analyses of the interviews. A semi-structured interview guide was applied with the topics: donation in general; donation for research; mental health and body organs; opinion regarding donation; feelings aroused by the topic. Although all participants were aware of organ donation for transplant, they were surprised that tissue could be donated for research. Nevertheless, once they understood the concept they were usually in favor of the idea. Although participants demonstrated a general lack of knowledge on donation for research, they were willing to learn more and viewed it as a good thing, with altruistic reasons often cited as a motive for donation. We speculate that bridging this knowledge gap may be a fundamental step towards a more ethical postmortem tissue donation process.

Self-assembly of an electronically conductive network through microporous scaffolds.

PubMed

Sebastian, H Bri; Bryant, Steven L

2017-06-15

Electron transfer spanning significant distances through a microporous structure was established via the self-assembly of an electronically conductive iridium oxide nanowire matrix enveloping the pore walls. Microporous formations were simulated using two scaffold materials of varying physical and chemical properties; paraffin wax beads, and agar gel. Following infiltration into the micropores, iridium nanoparticles self-assembled at the pore wall/ethanol interface. Subsequently, cyclic voltammetry was employed to electrochemically crosslink the metal, erecting an interconnected, and electronically conductive metal oxide nanowire matrix. Electrochemical and spectral characterization techniques confirmed the formation of oxide nanowire matrices encompassing lengths of at least 1.6mm, 400× distances previously achieved using iridium nanoparticles. Nanowire matrices were engaged as biofuel cell anodes, where electrons were donated to the nanowires by a glucose oxidizing enzyme. Copyright © 2017 Elsevier Inc. All rights reserved.

Carbon-tuned bonding method significantly enhanced the hydrogen storage of BN-Li complexes.

PubMed

Deng, Qing-ming; Zhao, Lina; Luo, You-hua; Zhang, Meng; Zhao, Li-xia; Zhao, Yuliang

2011-11-01

Through first-principles calculations, we found doping carbon atoms onto BN monolayers (BNC) could significantly strengthen the Li bond on this material. Unlike the weak bond strength between Li atoms and the pristine BN layer, it is observed that Li atoms are strongly hybridized and donate their electrons to the doped substrate, which is responsible for the enhanced binding energy. Li adsorbed on the BNC layer can serve as a high-capacity hydrogen storage medium, without forming clusters, which can be recycled at room temperature. Eight polarized H(2) molecules are attached to two Li atoms with an optimal binding energy of 0.16-0.28 eV/H(2), which results from the electrostatic interaction of the polarized charge of hydrogen molecules with the electric field induced by positive Li atoms. This practical carbon-tuned BN-Li complex can work as a very high-capacity hydrogen storage medium with a gravimetric density of hydrogen of 12.2 wt%, which is much higher than the gravimetric goal of 5.5 wt % hydrogen set by the U.S. Department of Energy for 2015.

Synthesis and fluorescence properties of some difluoroboron β-diketonate complexes and composite containing PMMA

NASA Astrophysics Data System (ADS)

Xing, Dongye; Hou, Yanjun; Niu, Haijun

2018-03-01

A series of difluoroboron β-diketonate complexes, containing the indon-β-diketonate ligand carrying methyl or methoxyl substituents was synthesized. The crystal structures of the complexes were confirmed by single crystal X-ray diffraction studies. The fluorescence properties of compounds were studied in solution state, solid state and on PMMA polymer matrix. The photophysical data of compounds 2a-2d exhibited strong fluorescence and photostability under the ultraviolet light (Hg lamp). The complex 2b showed higher fluorescence intensity in solution state as compared to other complexes of the series. The complexes 2c and 2d showed higher fluorescence intensity in the solid state, which are ascribed to the stronger π-π interactions between ligands in the solid state. The introduction of methoxyl or methyl groups on the benzene rings enhanced the absorption intensity, emission intensity, quantum yields and fluorescence lifetimes due to their electron-donating nature. Furthermore, the complex 2b was doped into the PMMA to produce hybrid materials, where the PMMA matrix acted as sensitizer for the central boron ion to enhance the fluorescence emission intensity and quantum yields.

Effects of axial coordination on immobilized Mn(salen) catalysts.

PubMed

Teixeira, Filipe; Mosquera, Ricardo A; Melo, André; Freire, Cristina; Cordeiro, M Natália D S

2014-11-13

The consequences of anchoring Mn(salen) catalysts onto a supporting material using one of the vacant positions of the metal center are tackled by studying several Mn(salen) complexes with different axial ligands attached. This is accomplished using Density Functional Theory at the X3LYP/Triple-ζ level of theory and the Atom In Molecules formalism. The results suggest that both Mn(salen) complexes and their oxo derivatives should lie in a triplet ground state. Also, the choice of the axial ligand bears a moderate effect on the energy involved in the oxidation of the former to oxo-Mn(salen) complexes, as well as in the stability of such complexes toward ligand removal by HCl. AIM analysis further suggests that the salen ligand acts as a "charge reservoir" for the metal center, with strong correlations being obtained between the charge of salen and the electron population donated by the axial ligand to the metal center. Moreover, the results suggest that the Mn atom in Mn(salen) complexes holds different hybridization of its valence orbitals depending on the type of axial ligand present in the system.

Sorption mechanism of enrofloxacin on humic acids extracted from Brazilian soils.

PubMed

Martínez-Mejía, Mónica J; Sato, Isabela; Rath, Susanne

2017-07-01

Veterinary antimicrobials are emerging environmental contaminants of concern. In this study, the sorption of enrofloxacin (ENR) onto humic acids (HAs) extracted from three Brazilian soils was evaluated. HAs were characterized by elemental analysis and solid 13 C nuclear magnetic resonance spectroscopy. The sorption of ENR onto HAs was at least 20-fold higher than onto the soils from which they were separated. Ionic and cation bridging are the primary interactions involved. The interactions driven by cation exchange are predominant on HAs, which appear to have abundant carboxylic groups and a relatively high proportion of H-bond donor moieties with carbohydrate-like structures. Interactions explained by cation bridging and/or surface complexation on HAs are facilitated by moieties containing conjugated ligands, significant content of oxygen-containing functional groups, such as phenolic-OH or lignin-like structures. HAs containing electron-donating phenolic moieties and carboxylic acid ligand groups exhibit a sorption mechanism that is primarily driven by strong metal binding, favoring the formation of ternary complexes between functional groups of the organic matter and drugs.

Electronic structure of the chiral helimagnet and 3d-intercalated transition metal dichalcogenide Cr 1/3NbS 2

DOE PAGES

Sirca, N.; Mo, S. -K.; Bondino, F.; ...

2016-08-18

The electronic structure of the chiral helimagnet Cr 1/3NbS 2 has been studied with core level and angle-resolved photoemission spectroscopy (ARPES). Intercalated Cr atoms are found to be effective in donating electrons to the NbS 2 layers but also cause significant modifications of the electronic structure of the host NbS 2 material. Specifically, the data provide evidence that a description of the electronic structure of Cr 1/3NbS 2 on the basis of a simple rigid band picture is untenable. The data also reveal substantial inconsistencies with the predictions of standard density functional theory. In conclusion, the relevance of these resultsmore » to the attainment of a correct description of the electronic structure of chiral helimagnets, magnetic thin films/multilayers, and transition metal dichalcogenides intercalated with 3d magnetic elements is discussed.« less

Applications of biochar in redox-mediated reactions.

PubMed

Yuan, Yong; Bolan, Nanthi; Prévoteau, Antonin; Vithanage, Meththika; Biswas, Jayanta Kumar; Ok, Yong Sik; Wang, Hailong

2017-12-01

Biochar is chemically more reduced and reactive than the original feedstock biomass. Graphite regions, functional groups, and redox-active metals in biochar contribute to its redox characteristics. While the functional groups such as phenolic species in biochar are the main electron donating moieties (i.e., reducers), the quinones and polycondensed aromatic functional groups are the components accepting electrons (oxidants). The redox capacity of biochar depends on feedstock properties and pyrolysis conditions. This paper aims to review and summarize the various synthesis techniques for biochars and the methods for probing their redox characteristics. We review the abiotic and microbial applications of biochars as electron donors, electron acceptors, or electron shuttles for pollutant degradation, metal(loid)s (im)mobilization, nutrient transformation, and discuss the underlying mechanisms. Furthermore, knowledge gaps that exist in the exploration and differentiation of the electron transfer mechanisms involving biochars are also identified. Copyright © 2017 Elsevier Ltd. All rights reserved.

41 CFR 102-37.520 - What is the authority for public airport donations?

Code of Federal Regulations, 2010 CFR

2010-07-01

... for public airport donations? 102-37.520 Section 102-37.520 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY Donations to Public Airports § 102-37.520 What is the authority for public airport donations? The authority for public airport donations is 49 U.S.C. 47151. 49 U...

41 CFR 102-37.520 - What is the authority for public airport donations?

Code of Federal Regulations, 2012 CFR

2012-01-01

... for public airport donations? 102-37.520 Section 102-37.520 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY Donations to Public Airports § 102-37.520 What is the authority for public airport donations? The authority for public airport donations is 49 U.S.C. 47151. 49 U...

41 CFR 102-37.520 - What is the authority for public airport donations?

Code of Federal Regulations, 2013 CFR

2013-07-01

... for public airport donations? 102-37.520 Section 102-37.520 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY Donations to Public Airports § 102-37.520 What is the authority for public airport donations? The authority for public airport donations is 49 U.S.C. 47151. 49 U...

41 CFR 102-37.520 - What is the authority for public airport donations?

Code of Federal Regulations, 2014 CFR

2014-01-01

... for public airport donations? 102-37.520 Section 102-37.520 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY Donations to Public Airports § 102-37.520 What is the authority for public airport donations? The authority for public airport donations is 49 U.S.C. 47151. 49 U...

41 CFR 102-37.520 - What is the authority for public airport donations?

Code of Federal Regulations, 2011 CFR

2011-01-01

... for public airport donations? 102-37.520 Section 102-37.520 Public Contracts and Property Management... 37-DONATION OF SURPLUS PERSONAL PROPERTY Donations to Public Airports § 102-37.520 What is the authority for public airport donations? The authority for public airport donations is 49 U.S.C. 47151. 49 U...

The Effect of Standardized Interviews on Organ Donation.

PubMed

Corman Dincer, Pelin; Birtan, Deniz; Arslantas, Mustafa Kemal; Tore Altun, Gulbin; Ayanoglu, Hilmi Omer

2018-03-01

Organ donation is the most important stage for organ transplant. Studies reveal that attitudes of families of brain-dead patients toward donation play a significant role in their decision. We hypothesized that supporting family awareness about the meaning of organ donation, including saving lives while losing a loved one, combined with being informed about brain death and the donation process must be maintained by intensive care unit physicians through standardized interviews and questionnaires to increase the donation rate. We retrospectively evaluated the final decisions of families of 52 brain-dead donors treated at our institution between 2014 and 2017. Data underwent descriptive analyses. The standard interview content was generated after literature search results were reviewed by the authors. Previously, we examined the impact of standardized interviews done by intensive care unit physicians with relatives of potential brain-dead donors regarding decisions to donate or reasons for refusing organ donation. After termination of that study, interviews were done according to the intensivist's orientation, resulting in significantly decreased donation rates. Standardized interviews were then started again, resulting in increased donation rates. Of 17 families who participated in standardized interviews, 5 families (29.4%) agreed to donate organs of their brain-dead relatives. In the other group of families, intensivists governed informing the families of donation without standardized interviews. In this group of 35 families, 5 families (14.3%) approved organ donation. The decision regarding whether to agree to organ donation was statistically different between the 2 family groups (P < .05). Conducting a standard interview between relatives of brain-dead donors and the intensivists, facilitating visits between relatives and the brain-dead patients, and informing relatives about the donation process resulted in an increased rate of organ donation compared with routine protocols.

Eye donation – Awareness and willingness among attendants of patients at various clinics in Melaka, Malaysia

PubMed Central

Bhandary, Sulatha; Khanna, Rajesh; Rao, Krishna A; Rao, Lavanya G; Lingam, Kamala D; Binu, V

2011-01-01

Aim: Corneal blindness accounts for 3.42% of blindness in Malaysia; the rate of eye donation is low. The aim of the study was to assess the awareness about eye donation and willingness to donate eyes among attendants of patients at various clinics in Melaka, Malaysia. Materials and Methods: This observational study was conducted on attendants who accompanied patients (n = 400) visiting various outpatient departments of the General Hospital and two peripheral clinics in Melaka between August and October 2007. The participants answered a questionnaire (Malay and English versions) which included demographic profile, awareness of eye donation, knowledge regarding facts of eye donation, and willingness to donate eyes. Univariate and multivariate logistic regression was performed at 5% level of significance. Results: Awareness of eye donation was observed in 276 (69%) participants. Multivariate analysis showed that awareness was more among females when compared to males (P = 0.009). Of the 276 participants who were aware of eye donation, only 34.42% were willing to donate eyes. Willingness was more among the Indian race (P = 0.02) and males (P = 0.02). Educational status did not influence the willingness to donate eyes. Conclusions: Although majority of participants were aware of eye donation, willingness to donate eyes was poor. PMID:21157071

Evolution of a Fourth Generation Catalyst for the Amination and Thioetherification of Aryl Halides

PubMed Central

Hartwig, John F.

2010-01-01

Conspectus Synthetic methods to form the carbon-nitrogen bonds in aromatic amines are fundamental enough to be considered part of introductory organic courses. Arylamines are important because they are common precursors to or substructures within active pharmaceutical ingredients and herbicides produced on ton scales, as well as conducting polymers and layers of organic light-emitting diodes produced on small scale. For many years, this class of compound was prepared from classical methods, such as nitration, reduction and reductive alkylation, copper-mediated chemistry at high temperatures, addition to benzyne intermediates, or direct nucleophilic substitution on particularly electron-poor aromatic or heteroaromatic halides. During the past decade, these methods to form aromatic amines have been largely supplanted by palladium-catalyzed coupling reactions of amines with aryl halides. The scope and efficiency of the palladium-catalyzed processes has gradually improved with successive generations of catalysts to the point of being useful for the synthesis of both milligrams and kilograms of product. This Account describes the conceptual basis and utility of our latest, “fourth-generation” catalyst for the coupling of amines and related reagents with aryl halides. The introductory sections of this account describe the progression of catalyst development from the first-generation to current systems and the motivation for selection of the components of the fourth-generation catalyst. This progression began with catalysts containing palladium and sterically hindered monodentate aromatic phosphines used initially for coupling of tin amides with haloarenes in the first work on C-N coupling. A second generation of catalysts was then developed based on the combination of palladium and aromatic bisphosphines. These systems were then followed by third-generation systems catalysts on the combination of palladium and a sterically hindered alkylmonophosphine or N-heterocyclic carbene. During the past five years, we have studied a fourth-generation catalyst for these reactions containing ligands that combine the chelating properties of the second-generation systems with the steric hindrance and strong electron donation of the third-generation systems. This combination has created a catalyst that couples aryl chlorides, bromides and iodides with primary amines, N-H imines, and hydrazones in high yield, with broad scope, high functional group tolerance, nearly perfect selectivity for monoarylation, and the lowest levels of palladium that have been used for C-N coupling. This catalyst is based on palladium and a sterically hindered version of the Josiphos family of ligands that possesses a ferrocenyl-1-ethylbackbone, a hindered di-tert-butylphosphino group, and a hindered dicyclohexylphosphino group. This latest generation of catalyst not only improves the coupling of primary amines and related nucleophiles, but it has dramatically improved the coupling of thiols with haloarenes to form C-S bonds. This catalyst system couples both aliphatic and aromatic thiols with chloroarenes with much greater scope, functional group tolerance, and turnover numbers than had been observed previously. The effects of structural features of the Josiphos ligand on catalyst activity have been revealed by examining the reactivity of catalysts generated from ligands lacking one or more of the structural elements of the most active catalyst. These modified ligands lack the relative stereochemistry of the ferrocenyl-1-ethyl backbone, the strong electron donation of the dialkylphosphino groups, the steric demands of the alkylphosphine groups, or the stability of the ferrocenyl unit. This set of studies showed that each one of these structural features contributed to the high reactivity and selectivity of the catalyst containing the hindered, bidentate Josiphos ligand. Finally, a series of studies on the effect of electronic properties on the rates of reductive elimination have recently distinguished between the effect of the properties of the M-N σ-bond and the nitrogen electron pair on the rate of reductive elimination. These studies have shown that the effect of substituents attached to the metal-bound nitrogen or carbon atoms on the rate of reductive elimination are similar. Because the amido ligands contain an electron pair, while the alkyl ligands do not, we have concluded that the major electronic effect is transmitted through the σ-bond. In other words, we have concluded that the electronic effect on the metal-nitrogen σ bond dominates an electronic effect on the nitrogen electron pair. PMID:18681463

The adsorption of Run (n = 1-4) on γ-Al2O3 Surface: A DFT study

NASA Astrophysics Data System (ADS)

Liu, Zhe; Guo, Yafei; Chen, Yu; Shen, Rong

2018-05-01

The density functional theory (DFT) was adopted to study the adsorption and growth of Run (n = 1-4) clusters on γ-Al2O3 surface, which is of great significances for the design of many important catalysts, especially for carbon dioxide methanation. It is found that both the Rusbnd Ru bond length and adsorption energy Eads of Ru clusters with the surface increase with the Run clusters increasing. The growth ability of the supported Run cluster is weaker than the gas phase Run clusters through comparing their respective growth process, which ascribes to the stabilization of γ-Al2O3 support. An interesting discovery is that the basin structure was supposed to be the most favorable adsorption geometry for Run clusters. Additionally, the distances between Ru atoms in the adsorbed clusters are longer than that in their isolated counterparts. Bader charge analysis was conducted for the most stable configurations of Run (n = 1-4) clusters on γ-Al2O3 surface as well. And the results suggest that Run (n = 1-4) clusters serve as the electron donators. The result of projected density of states (PDOS) shows that strong adsorption of Ru atom on the γ-Al2O3 surface correlates with strong interaction between d orbital of Ru atom and p orbital of Al or O atom of the Al2O3 support.

Donation return time at fixed and mobile donation sites

PubMed Central

Carey, Patricia M.; High, Patrick M.; Schlumpf, Karen S.; Johnson, Bryce R.; Mast, Alan E.; Rios, Jorge A.; Simon, Toby L.; Wilkinson, Susan L.

2013-01-01

BACKGROUND This study investigated the effect of blood donation environment, fixed or mobile with differing sponsor types, on donation return time. STUDY DESIGN AND METHODS Data from 2006 through 2009 at six US blood centers participating in the Retrovirus Epidemiology Donor Study-II (REDS-II) were used for analysis. Descriptive statistics stratified by whole blood (WB), plateletpheresis (PP), and double red blood cell (R2) donations were obtained for fixed and mobile locations, including median number of donations and median interdonation interval. A survival analysis estimated median return time at fixed and mobile sites, while controlling for censored return times, demographics, blood center, and mandatory recovery times. RESULTS Two-thirds (67.9%) of WB donations were made at mobile sites, 97.4% of PP donations were made at fixed sites, and R2 donations were equally distributed between fixed and mobile locations. For donations at fixed sites only or alternating between fixed and mobile sites, the highest median numbers of donations were nine and eight, respectively, and the shortest model-adjusted median return times (controlling for mandatory eligibility times of 56 and 112 days) were 36 and 30 days for WB and R2 donations, respectively. For PP donations, the shortest model-adjusted median return time was 23 days at a fixed location and the longest was 693 days at community locations. CONCLUSION WB, PP, and R2 donors with the shortest time between donations were associated with fixed locations and those alternating between fixed and mobile locations, even after controlling for differing mandatory recovery times for the different blood donation procedures. PMID:21745215

An analysis of knowledge and attitudes of hospice staff towards organ and tissue donation.

PubMed

Wale, J; Arthur, A; Faull, C

2014-03-01

Only a minority of hospice patients eligible to donate tissue and organs choose to do so. Hospice care staff play a key role in discussions about donation, but their willingness to engage in these discussions and their understanding of issues around tissue and organ donation is poorly understood. To (i) identify factors associated with the wish of hospice doctors, nurses and healthcare assistants to donate their own organs after death; (ii) survey the experience of discussing the subject with patients; (iii) determine staff members' knowledge of organ and tissue donation and (iv) identify factors associated with knowledge of organ and tissue donation. Cross-sectional questionnaire survey of hospice care staff. 76 of the 94 care staff of one large UK hospice completed and returned the questionnaire. Staff wishing to donate their organs after death (43/76 56.6%) were more likely to be doctors or nurses than healthcare assistants (p=0.011) and more likely to have discussed organ or tissue donation with their family (p<0.001). Staff reporting ever having discussed donation with patients had more years' experience (p=0.045) and had similarly discussed donation with their own family (p=0.039). Those with greater knowledge were more likely to have discussed organ or tissue donation with a patient (p=0.042). A reluctance to instigate discussions about organ and tissue donation may prevent palliative patients and their families being allowed the opportunity to donate. Suboptimal knowledge among hospice staff suggests the need for greater liaison between hospice staff, and the organ and tissue donation teams.

First-time whole blood donation: A critical step for donor safety and retention on first three donations.

PubMed

Gillet, P; Rapaille, A; Benoît, A; Ceinos, M; Bertrand, O; de Bouyalsky, I; Govaerts, B; Lambermont, M

2015-01-01

Whole blood donation is generally safe although vasovagal reactions can occur (approximately 1%). Risk factors are well known and prevention measures are shown as efficient. This study evaluates the impact of the donor's retention in relation to the occurrence of vasovagal reaction for the first three blood donations. Our study of data collected over three years evaluated the impact of classical risk factors and provided a model including the best combination of covariates predicting VVR. The impact of a reaction at first donation on return rate and complication until the third donation was evaluated. Our data (523,471 donations) confirmed the classical risk factors (gender, age, donor status and relative blood volume). After stepwise variable selection, donor status, relative blood volume and their interaction were the only remaining covariates in the model. Of 33,279 first-time donors monitored over a period of at least 15 months, the first three donations were followed. Data emphasised the impact of complication at first donation. The return rate for a second donation was reduced and the risk of vasovagal reaction was increased at least until the third donation. First-time donation is a crucial step in the donors' career. Donors who experienced a reaction at their first donation have a lower return rate for a second donation and a higher risk of vasovagal reaction at least until the third donation. Prevention measures have to be processed to improve donor retention and provide blood banks with adequate blood supply. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Voluntary Blood Donation among Students - A Cross-Sectional Study on Knowledge and Practice vs. Attitude

PubMed Central

Pehlajani, Nand K.; Sinha, Mithilesh K.

2016-01-01

Introduction The factors influencing blood donation decisions are varied and complex and one’s attitude can influence this decision. Aim To find the factors affecting the knowledge and practice of blood donation among college students and their attitude towards the same. Materials and Methods This cross-sectional study was conducted among 399 college going students using convenience sampling from medical, nursing and engineering colleges in Bhubaneswar city, where blood donation camps were to be held. Data was collected through self-administered questionnaires and, analysed in SPSS Version 20.0. Results Knowledge regarding blood donation was adequate among 228 (57.1%) of the students and, 221 (55.4%) students had donated blood. Knowledge was significantly better among female students, medical stream and in those whose parents were in non-medical jobs; whereas blood donation had been done significantly more by male, non-medical stream students and by those whose parents were in medical field. Most common reason for donating blood was a sense of social responsibility and most common reason of non-donation was fear of the procedure. An 85% of the students were of the view that they would donate blood if asked. Students suggested that small incentives like certificates and arranging transport for blood donation would make it easier to donate. Conclusion Just over half of the students had adequate knowledge about blood donation and similar percentage had donated blood. There is this large pool of safe blood in college going students who are willing, but not tapped as source of blood donation. PMID:27891345

Analysis of Chinese Donors’ Return Behavior

PubMed Central

Guo, Nan; Wang, Jingxing; Ness, Paul; Yao, Fuzhu; Dong, Xiangdong; Bi, Xinhong; Mei, Heili; Li, Julin; He, Weilan; Lu, Yunlai; Ma, Hongli; Wen, Xiuqiong; Huang, Mei; Wright, David J.; King, Melissa; High, Patrick; Nelson, Kenrad; Shan, Hua

2010-01-01

Background It is important to understand donor return behavior. Converting first time donors to become repeat donors is essential for maintaining an adequate blood supply. Methods Characteristics of 241,552 whole blood (WB) donations from first time (FT) and repeat (RPT) donors who donated in 2008 at the 5 blood centers in China were compared. A subset of 54,394 WB donors who donated between January 1 and March 31, 2008 were analyzed for their return behavior in 2008 following the index donation using logistic regression. Results Of all donations, 64% was from FT donors. Donors with self-reported previous donations tended to be male, older, married, donated larger volume (≥300mL), and were heavier in weight. Among donors who donated from January to March, 2008, 14% returned for subsequent WB donations by the end of 2008. The number of previous donations and blood collection location were the two strongest predictors for making subsequent donations. Donors with 1, 2–3 and more than 3 previous donations were 3.7, 5.7, and 11.0 times more likely to return than FT donors. Those who donated in a blood collection vehicle were 4 times more likely to return than those who donated at a blood center. Being female, younger and of a lower education level (≤ middle school) were positively associated with subsequent return blood donation during the follow-up period observed in this study. Conclusion Most of the Chinese blood supply is from first time donors. Strategies aimed at encouraging current donors to become repeat donors are needed. PMID:20849408

Broadband All-Polymer Phototransistors with Nanostructured Bulk Heterojunction Layers of NIR-Sensing n-Type and Visible Light-Sensing p-Type Polymers

PubMed Central

Han, Hyemi; Nam, Sungho; Seo, Jooyeok; Lee, Chulyeon; Kim, Hwajeong; Bradley, Donal D. C.; Ha, Chang-Sik; Kim, Youngkyoo

2015-01-01

We report ‘broadband light-sensing’ all-polymer phototransistors with the nanostructured bulk heterojunction (BHJ) layers of visible (VIS) light-sensing electron-donating (p-type) polymer and near infrared (NIR) light-sensing electron-accepting (n-type) polymer. Poly[{2,5-bis-(2-ethylhexyl)-3,6-bis-(thien-2-yl)-pyrrolo[3,4-c]pyrrole-1,4-diyl}-co-{2,2′-(2,1,3-benzothiadiazole)]-5,5′-diyl}] (PEHTPPD-BT), which is synthesized via Suzuki coupling and employed as the n-type polymer, shows strong optical absorption in the NIR region (up to 1100 nm) in the presence of weak absorption in the VIS range (400 ~ 600 nm). To strengthen the VIS absorption, poly(3-hexylthiophene) (P3HT) is introduced as the p-type polymer. All-polymer phototransistors with the BHJ (P3HT:PEHTPPD-BT) layers, featuring a peculiar nano-domain morphology, exhibit typical p-type transistor characteristics and efficiently detect broadband (VIS ~ NIR) lights. The maximum corrected responsivity (without contribution of dark current) reaches up to 85 ~ 88% (VIS) and 26 ~ 40% (NIR) of theoretical responsivity. The charge separation process between P3HT and PEHTPPD-BT components in the highest occupied molecular orbital is proposed as a major working mechanism for the effective NIR sensing. PMID:26563576

Awareness and attitudes towards organ donation among medical students at King Abdulaziz University, Jeddah, Saudi Arabia.

PubMed

Sayedalamin, Zaid; Imran, Muhammad; Almutairi, Osama; Lamfon, Mohammed; Alnawwar, Majd; Baig, Mukhtiar

2017-04-01

To assess awareness and attitude of medical students about organ donation. This cross-sectional study was conducted in 2014 at King Abdulaziz University, Jeddah, Saudi Arabia, and comprised medical students. The participants were asked about their religious and other beliefs towards organ donation, their reasons for not donating organs, and their personal opinions about organ donation through a questionnaire. SPSS 21 was used for data analysis. Of the 481 participants, 250(52%) were females, and 231(48%) were males. The overall mean age was 21.36±1.63 years. Besides, 437(90.9%) students knew what organ donation means, 433(90%) supported organ donation, and 90(18.7%) knew someone who had donated an organ. Moreover, 245(50.9%) participants were willing to donate their organ to their family alone, 198(41.2%) were willing to donate to any deserving patient while 439(91.3%) rejected that religion precluded organ donation, and 354(73.6%) did not know about the grafting of organs from a man to a woman and vice versa. Awareness and attitude towards organ donation were not up to the mark among the participants.

Living donation decision making: recipients' concerns and educational needs.

PubMed

Waterman, Amy D; Stanley, Sara L; Covelli, Tonie; Hazel, Erik; Hong, Barry A; Brennan, Daniel C

2006-03-01

Despite the advantages of living donor transplantation, evidence suggests that some potential recipients with living donors have psychological concerns that prevent them from pursuing living donation. Addressing these concerns through education may increase the rates of living donation. To understand the psychological barriers and educational needs of potential kidney recipients regarding living donation. Qualitative focus group study of kidney transplant recipients, donors, and family members to explore their assessment of the advantages of dialysis and deceased donor transplantation over living donation, their concerns about living donation, and what types of living donation education would be most helpful. Kidney recipients reported that they might not pursue living donation because they felt guilty and indebted to the donor, did not want to harm or inconvenience the donor, did not want to accept a kidney that a family member might need later, and did not want to disappoint the donor if the kidney failed. Recipients were generally unaware that donors could personally benefit from donating and would rather wait for donor volunteers than ask anyone directly. Both donors and recipients thought that training on how to make the donation request and education about living donors' motivations for donation and transplant experience could help more renal patients pursue living donation.

Are Older Adults More Willing to Donate? The Roles of Donation Form and Social Relationship.

PubMed

Gong, Xianmin; Zhang, Fan; Fung, Helene H

2017-07-21

Whether older adults are more prosocial than younger adults has been under debate. In the current study, we investigated how age differences in prosocial behaviors varied across different contextual factors, that is, donation form, kinship, and social distance. To achieve this purpose, 89 younger and 66 older adults took part in a hypothetical donation task in which they were asked to donate money and time to relatives and nonrelatives at various social distances. The results showed that, compared to younger adults, (a) older adults donated less to nonrelatives (regardless of the donation form), but donated a similar amount (in money) or even donated more (in time) to relatives; (b) older adults displayed higher levels of kin selection (favoring relatives over nonrelatives) in both monetary and time donations; and (c) older adults showed higher levels of social discounting (favoring socially close over distant others) in monetary but not time donation. The study underscored the importance of contextual factors in understanding age differences in prosocial behaviors such as donation. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Attitudes toward organ donation among personnel from the University Hospital of Rabat.

PubMed

Flayou, Kaoutar; Kouam, Nada; Miara, H; Raoundi, O; Ouzeddoun, Naima; Benamar, Loubna; Bayahia, Rabiaa; Rhou, Hakima

2016-01-01

The medical staff could play a major role in promoting for organ donation. The aim of our study was to assess the attitudes of the medical staff toward organ donation. It is a prospective study conducted over a period of six months. A questionnaire was distributed and explained to the medical staff in our institute. Fifteen questions were designed to include four main themes: sociodemographic information, attitude toward organ donation, perceived knowledge about organ donation, and reasons for refusal or acceptance of organ donation. Among the 245 respondents, 36.3% had prior knowledge about organ transplantation, 31.8% knew about the law of organ donation, 43.2% had already donated blood sometimes, 65.7% expressed their consent to organ donation during their lifetime, and 82.8% expressed their agreement to donation after their death. The grounds for refusal were generally: a misunderstanding of risks, desire for respect of corpse. The religious and the ethical motive were present too as a ground for decision making. The medical staff is the key for organ donation. To promote organ transplantation, personnel should be well informed about ethical, moral, and religious dimensions of organ donation and transplantation.

Knowledge and behavior towards voluntary blood donation among students of a tertiary institution in Nigeria.

PubMed

Salaudeen, A G; Odeh, E

2011-01-01

Blood donation is the only way of acquiring blood to meet emergency requirements in cases of road traffic accidents, complications of pregnancy and childbirth, various anemic disorders and surgical emergencies among others. Globally, 80 million units of blood are donated each year, but only two million units are donated in sub-Saharan Africa where the need is enormous. The objective of this study was to determine the behavior of the students of a tertiary institution in Nigeria towards voluntary blood donation. This is a descriptive cross-sectional study, which involved students of a tertiary institution in Nigeria. A multistage sampling technique was employed in selecting the participants for this study. A semi-structured self-administered questionnaire was used to collect information on socio-demographic characteristics, knowledge, attitude and factors affecting voluntary blood donation. The data obtained were analyzed using EPI-INFO 2005 software Version 3.3.2. Less than two-thirds (61%) of total respondents had good knowledge of blood donation. More than three quarters (85%) of the respondents had never donated blood. Of the 15% that had donated, only 3% donated voluntarily. Among those that had ever donated, males (57%) were more than females. Many of the donors donated for relatives (57%). The majority of the respondents were compelled to donate because of emergency situations (75%). The reasons why many did not donate were lack of opportunity (45%) due to tight lecture schedule and inadequate knowledge (24%). Gift items such as hematinics, T-shirts and wrist bands (29%) would motivate respondents to donate. The Students' Union body and other Organizations in the University should include a blood donation drive in their monthly/annual activities. The University authorities, the University health service centre and the Hematology Department of the Teaching hospital should collaborate in promoting voluntary blood donation among the students.

Public awareness of blood donation in Central Saudi Arabia

PubMed Central

Abolfotouh, Mostafa A; Al-Assiri, Mohammed H; Al-Omani, Manar; Al Johar, Alwaleed; Al Hakbani, Abdulaziz; Alaskar, Ahmed S

2014-01-01

Introduction In Saudi Arabia, voluntary donors are the only source of blood donation. The aim of this study was to assess the level of public knowledge and attitude toward blood donation in Saudi Arabia. Methods Using a previously validated questionnaire that comprises 38 questions to assess the levels of knowledge, attitudes, and motivations towards blood donation, 469 Saudi adults who attended different shopping malls in Riyadh, Saudi Arabia were surveyed. Multiple regression analyses were used to identify the significant predictors of blood donation, with the significance set at P<0.05. Results Approximately half of all subjects (53.3%) reported that they had previously donated blood, 39% of whom had donated more than once. The knowledge percentage mean score was 58.07%, denoting a poor level of knowledge, with only 11.9% reporting a good level of knowledge. The attitude percentage mean score towards donation was 75.45%, reflecting a neutral attitude towards donating blood, with 31.6% reporting a positive attitude. Donation was significantly more prevalent among males than females (66% versus 13.3%; P<0.001). After adjustment for confounders, a higher knowledge score (t=2.59; P=0.01), a higher attitude score (t=3.26; P=0.001), and male sex (t=10.45; P<0.001) were significant predictors of blood donation. An inability to reach the blood donation centers and a fear of anemia were the main reasons for females not donating blood (49.9% and 35.7%, respectively), whereas a lack of time was the main reason for males (59.5%). Conclusion Prevalence of blood donation was less than satisfactory among the Saudi public, probably due to misconceptions, poor knowledge, and unfavorable attitude to donation. Educational programs are necessary to increase the level of knowledge and improve the attitude of the Saudi public toward blood donation. Providing mobile blood collection units nearer to individuals’ places of work to reduce their time costs of donating is a necessity. PMID:25152628

Blood donation behaviour and beliefs among a sample of high school students in Mmabatho.

PubMed

Mwaba, K; Keikelame, M J

1995-08-01

This study was aimed at establishing the extent of blood donation and beliefs about donating blood among high school students in Mmabatho. A random sample of 40 Standard 10 students (20 males, 20 females; mean age = 20.8 years) was selected to participate in the study. A structured questionnaire was used to determined blood donation behaviour and accompanying beliefs. The results showed that although 80 percent of the participants believed that donating blood was important only 17.5 percent had actually ever donated blood. The data also showed that donating blood was a health risk or were uncertain if donating blood was safe. It is recommended that public appeals for blood donors should include information to dispel myths about dangers of donating blood.

Absence of significant dissent should be sufficient for deceased donor organ procurement in New Zealand.

PubMed

Douglas, Thomas M; Douglas, Nicholas M

2009-10-01

New Zealand's organ donation rates are among the lowest in the OECD. In a bid to increase organ availability, the New Zealand Human Tissue Act 2008 introduces new consent arrangements for deceased donor organ procurement. This article assesses these new arrangements and presents the case for further reform. Our assessment and arguments are based on philosophical analysis informed by empirical data on the effectiveness of alternative consent systems. We: 1) Identify widely held ethical judgments about policies and practices relevant to organ donation (e.g. those relating to coronial post-mortems), 2) Assess the implications of these judgments for the Human Tissue Act and the assumptions that underpin it, and 3) Derive policy recommendations that are consistent with the judgments. The Human Tissue Act 2008 retains a strong consent requirement for organ procurement: organs may not be transplanted unless either the deceased or the family consents. We argue that organ availability could and should be increased by shifting from a model that requires consent to one that requires the absence of significant dissent. We recommend that New Zealand adopt either 1) an organ donation system similar to the existing system for ordering coronial post-mortems, or 2) a variant of the 'opt-out' system already in place in several other countries.

Genetic polymorphisms of serotonin transporter and receptor 1A could influence success during embryo implantation and maintenance of pregnancy.

PubMed

Palomares, Arturo R; Lendínez-Ramírez, Ana M; Pérez-Nevot, Beatriz; Cortés-Rodríguez, Miriam; Martínez, Francisco; Garrido, Nicolás; Ruiz-Galdón, Maximiliano; Reyes-Engel, Armando

2013-06-01

To explore whether serotonin-related gene polymorphisms influence clinical outcomes of IVF treatment in recipients using donated oocytes. Nested case-control study. University-affiliated infertility clinic. Two hundred forty-five women undergoing IVF treatment with donated oocytes. None. Genotype and haplotype analysis of the serotonin transporter-linked polymorphic region (5-HTTLPR), rs1800532, rs6295, rs6313, and rs3813929, between recipients grouped according to the results of the oocyte donation for IVF treatment. No differences were found between genotype distribution of the tryptophan hydroxylase 1, serotonin receptor 2A, and serotonin receptor 2C polymorphisms. Recipients carrying the LL genotype for 5-HTTLPR had lower clinical pregnancy rates (PR) and higher biochemical pregnancy loss (BPL) events. Lower implantation rates were found in CC carriers for 5-HT1A.rs6295 who also presented higher BPL rates. A lower incidence of clinical pregnancy was observed for LC haplotypes, corresponding to an increase in BPL rates. A strong association was found between early pregnancy loss and recipients carrying the 5-HTTLPR and rs6295 genetic variants. Identifying biological processes involving serotonin and embryo implantation may help to understand the dynamics of the maternal-embryo dialogue. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Asian American adolescents' willingness to donate organs and engage in family discussion about organ donation and transplantation.

PubMed

Trompeta, Joyce A; Cooper, Bruce A; Ascher, Nancy L; Kools, Susan M; Kennedy, Christine M; Chen, Jyu-Lin

2012-03-01

Despite the growing need for organ donation among Asian Americans, studies suggest that they are reluctant to donate. To examine the association of attitudes and knowledge about organ donation and transplantation with willingness to donate and willingness to engage in family discussion about organ donation among Asian American adolescents. A cross-sectional study. The Big Island of Hawaii. Self-identified Asian American adolescents (Japanese, Chinese, Filipino, Korean), ages 16 to 17 years old, and each adolescent's parent or guardian. Asian American adolescents provided demographic information and completed the Modified Organ Donation Attitude Survey, the Organ Donation and Transplantation Knowledge Survey, and the Suinn-Lew Asian Self-Identity Acculturation Scale. A parent or guardian also provided demographic information. Linear regression analyses were used to examine the associations with willingness to donate and to engage in family discussion about organ discussion. Willingness to donate was associated with positive knowledge related to general aspects about organ donation and cultural limitations in receiving an organ transplant, a high level of acculturation, and a low level of negative attitudes (R2 = 0.402, F = 18.86, P = .005). Asian American adolescents with approving or positive attitudes were likely to engage in family discussion about organ donation (R2 = 0.195, F = 27.93, P = .005). To reinforce and maintain high levels of knowledge and positive attitudes, organ donation education is most likely needed in high schools.

Examination of the Mechanism of Rh2(II)-Catalyzed Carbazole Formation Using Intramolecular Competition Experiments

PubMed Central

Stokes, Benjamin J.; Richert, Kathleen J.; Driver, Tom G.

2009-01-01

The use of a rhodium(II) carboxylate catalyst enables the mild and stereoselective formation of carbazoles from biaryl azides. Intramolecular competition experiments of triaryl azides suggested the source of the selectivity. A primary intramolecular kinetic isotope effect was not observed and correlation of the product ratios with Hammett σ+-values produced a plot with two intersecting lines with opposite ρ-values. These data suggest that electronic donation by the biaryl π-system accelerates the formation of rhodium nitrenoid and that C–N bond formation occurs through a 4π-electron-5-atom electrocyclization. PMID:19663433

Increasing access to kidney transplantation for sensitized recipient through three-way kidney paired donation with desensitization: The first Indian report

PubMed Central

Kute, Vivek B; Patel, Himanshu V; Shah, Pankaj R; Modi, Pranjal R; Shah, Veena R; Rizvi, Sayyed J; Pal, Bipin C; Modi, Manisha P; Shah, Priya S; Varyani, Umesh T; Wakhare, Pavan S; Shinde, Saiprasad G; Ghodela, Viajay A; Patel, Minaxi H; Trivedi, Varsha B; Trivedi, Hargovind L

2016-01-01

The combination of kidney paired donation (KPD) with desensitization represents a promising method of increasing the rate of living donor kidney transplantation (LDKT) in immunologically challenging patients. Patients who are difficult to match and desensitize due to strong donor specific antibody are may be transplanted by a combination of desensitization and KPD protocol with more immunologically favorable donor. We present our experience of combination of desensitization protocol with three-way KPD which contributed to successful LDKT in highly sensitized end stage renal disease patient. All recipients were discharged with normal and stable allograft function at 24 mo follow up. We believe that this is first report from India where three-way KPD exchange was performed with the combination of KPD and desensitization. The combination of desensitization protocol with KPD improves access and outcomes of LDKT. PMID:27803919

Public health works: blood donation in urban China.

PubMed

Adams, Vincanne; Erwin, Kathleen; Le, Phuoc V

2009-02-01

Recent shifts in the global health infrastructure warrant consideration of the value and effectiveness of national public health campaigns. These shifts include the globalization of pharmaceutical research, the rise of NGO-funded health interventions, and the rise of biosecurity models of international health. We argue that although these trends have arisen as worthwhile responses to actual health needs, it is important to remember the key role that public health campaigns can play in the promotion of national health, especially in developing nations. Focusing on an example set by China in response to a public health crisis surrounding the national need for a clean and adequate blood supply and the inadvertent spread of HIV by way of blood donation in the early 1990's, we argue that there is an important role for strong national public health programs. We also identify the key factors that enabled China's response to this burgeoning epidemic to be, in the end, largely successful.

Synthesis of pyridine-fused perylene imides with an amidine moiety for hydrogen bonding.

PubMed

Ito, Satoru; Hiroto, Satoru; Shinokubo, Hiroshi

2013-06-21

Pyridine-fused perylene tetracarboxylic acid bisimides (PBIs) were synthesized via Suzuki-Miyaura coupling and acid condensation. The fused PBIs with electron-donating substituents exhibited an intramolecular charge transfer interaction. One of the N-alkyl substituents was selectively removed with BBr3 to create an amidine guest binding site. A hydrogen bonding interaction with pentafluorobenzoic acid changed the absorption spectra and enhanced fluorescence.

Methemoglobinemia caused by 8-aminoquinoline drugs: DFT calculations suggest an analogy to H4B's role in nitric oxide synthase

USDA-ARS?s Scientific Manuscript database

We suggest a possible mechanism of how 8-aminoquinolines (8-AQ's) cause hemotoxicity by oxidizing hemoglobin to methemoglobin. In our DFT calculations, we found that 5-hydroxyprimaquine is able to donate an electron to O2 to facilitate its conversion to H2O2. Meanwhile, Fe(II) is oxidized to Fe(III)...

41 CFR 109-44.702 - Donations to public bodies.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Donations to public... AND DISPOSAL 44-DONATION OF PERSONAL PROPERTY 44.7-Donations of Property to Public Bodies § 109-44.702 Donations to public bodies. ...

45 CFR 2544.115 - Who may offer a donation?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 45 Public Welfare 4 2010-10-01 2010-10-01 false Who may offer a donation? 2544.115 Section 2544... COMMUNITY SERVICE SOLICITATION AND ACCEPTANCE OF DONATIONS § 2544.115 Who may offer a donation? Anyone... donation to the Corporation. ...

45 CFR 2544.115 - Who may offer a donation?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 45 Public Welfare 4 2012-10-01 2012-10-01 false Who may offer a donation? 2544.115 Section 2544... COMMUNITY SERVICE SOLICITATION AND ACCEPTANCE OF DONATIONS § 2544.115 Who may offer a donation? Anyone... donation to the Corporation. ...

45 CFR 2544.115 - Who may offer a donation?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 45 Public Welfare 4 2014-10-01 2014-10-01 false Who may offer a donation? 2544.115 Section 2544... COMMUNITY SERVICE SOLICITATION AND ACCEPTANCE OF DONATIONS § 2544.115 Who may offer a donation? Anyone... donation to the Corporation. ...

41 CFR 109-44.702 - Donations to public bodies.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Donations to public... AND DISPOSAL 44-DONATION OF PERSONAL PROPERTY 44.7-Donations of Property to Public Bodies § 109-44.702 Donations to public bodies. ...

41 CFR 109-44.702 - Donations to public bodies.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Donations to public... AND DISPOSAL 44-DONATION OF PERSONAL PROPERTY 44.7-Donations of Property to Public Bodies § 109-44.702 Donations to public bodies. ...

45 CFR 2544.115 - Who may offer a donation?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 45 Public Welfare 4 2013-10-01 2013-10-01 false Who may offer a donation? 2544.115 Section 2544... COMMUNITY SERVICE SOLICITATION AND ACCEPTANCE OF DONATIONS § 2544.115 Who may offer a donation? Anyone... donation to the Corporation. ...

41 CFR 109-44.702 - Donations to public bodies.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Donations to public... AND DISPOSAL 44-DONATION OF PERSONAL PROPERTY 44.7-Donations of Property to Public Bodies § 109-44.702 Donations to public bodies. ...

45 CFR 2544.115 - Who may offer a donation?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 45 Public Welfare 4 2011-10-01 2011-10-01 false Who may offer a donation? 2544.115 Section 2544... COMMUNITY SERVICE SOLICITATION AND ACCEPTANCE OF DONATIONS § 2544.115 Who may offer a donation? Anyone... donation to the Corporation. ...

41 CFR 109-44.702 - Donations to public bodies.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Donations to public... AND DISPOSAL 44-DONATION OF PERSONAL PROPERTY 44.7-Donations of Property to Public Bodies § 109-44.702 Donations to public bodies. ...

Importance of education in organ donation.

PubMed

Yilmaz, Tonguc Utku

2011-12-01

Transplanting is the sole therapy for the majority of organ insufficiencies, but the lack of organ donation limits transplanting. We evaluated the effect of education about "Organ Donation and Transplantation" over the false beliefs of the participants. This interventional study was performed in a military unit between January and March 2010. Data on organ donation and demographic characteristics were collected by a questionnaire. The researcher gave the lesson, and then collected the data by the same questionnaire 2 months later. The rate of volunteering for organ donation increased from 45.4% to 84.8% (P < .001). Rate of consent for organ donations by relatives increased from 41% to 80.3% (P < .001). Also, general knowledge about organ donation increased from 34.8% to 93.7% (P < .001). Wrong beliefs about organ donation disappeared after the education. The entire organ donation rate among the volunteer participants increased from 60% to 84% (P < .001). No significant relation was found between volunteering to donate organs, and education and economic status. Education could correct false information and might lead to higher organ donation rates. This education (which gave positive results in a military unit) could become widespread.

Willingness to communicate organ donation intention.

PubMed

McDonald, Deborah Dillon; Ferreri, Ruth; Jin, Carol; Mendez, Anthea; Smail, Julie; Balcom, Patricia; Shoemaker, Sheila; Kamuzora, Paul Lwekaza; Durham, Rebecca; Dibble, Jaqueline

2007-01-01

The study tested an intervention exposing people who planned to donate organs to written information about communicating with family their intention to donate organs. A pretest posttest double-blind experiment compared participants given written information about communicating with family and basic organ donation information, with participants given written information about only basic organ donation information. Participants included 109 adults who had not yet communicated their plans with family. Participants first responded to previous experience with organ donation, thoughts about organ donation, willingness to communicate with family about organ donation, and knowledge about organ donation. After reading the respective pamphlet, participants again responded to thoughts about communicating with their family and willingness to communicate with family. Both groups responded with the same high willingness to communicate before the intervention and a small but significant increase in willingness to communicate afterwards. Participants expressed a high degree of willingness to communicate about their organ donation intentions even though they had thus far not communicated their intentions. Factors in addition to willingness to communicate need to be identified in order to encourage better communication about organ donation intentions.

Encouraging family discussion on the decision to donate organs: the role of the willingness to communicate scale.

PubMed

Smith, Sandi W; Kopfman, Jenifer E; Lindsey, Lisa L Massi; Yoo, Jina; Morrison, Kelly

2004-01-01

Family discussion of organ donation has been found to double rates of family consent regarding organ donation. Therefore, family discussion is an important communication process to study in the effort to get more people to become organ donors. This investigation concerns the willingness to communicate about organ donation and its relationship to other variables and processes related to family discussion of organ donation. Previous research on willingness to communicate examined the antecedent variables of knowledge, attitude toward organ donation, and altruism. This research found that being willing to communicate about organ donation with one's family is related to prior thought and intent to sign an organ donor card, to perceiving organ donation messages as credible, and to feeling relatively low anxiety after reading organ donation messages. One week after being presented with the messages, willingness to communicate was found to be positively associated with worrying about the lack of donors, engaging in family discussion about organ donation, and having an organ donor card witnessed. It was negatively related to feeling personally uneasy about organ donation during the past week.

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

Harwood, Caroline S.

This project is to develop and apply techniques in metabolic engineering to improve the biocatalytic potential of the bacterium Rhodopseudomonas palustris for nitrogenase-catalyzed hydrogen gas production. R. palustris, is an ideal platform to develop as a biocatalyst for hydrogen gas production because it is an extremely versatile microbe that produces copious amounts of hydrogen by drawing on abundant natural resources of sunlight and biomass. Anoxygenic photosynthetic bacteria, such as R. palustris, generate hydrogen and ammonia during a process known as biological nitrogen fixation. This reaction is catalyzed by the enzyme nitrogenase and normally consumes nitrogen gas, ATP and electrons. Themore » applied use of nitrogenase for hydrogen production is attractive because hydrogen is an obligatory product of this enzyme and is formed as the only product when nitrogen gas is not supplied. Our challenge is to understand the systems biology of R. palustris sufficiently well to be able to engineer cells to produce hydrogen continuously, as fast as possible and with as high a conversion efficiency as possible of light and electron donating substrates. For many experiments we started with a strain of R. palustris that produces hydrogen constitutively under all growth conditions. We then identified metabolic pathways and enzymes important for removal of electrons from electron-donating organic compounds and for their delivery to nitrogenase in whole R. palustris cells. For this we developed and applied improved techniques in 13C metabolic flux analysis. We identified reactions that are important for generating electrons for nitrogenase and that are yield-limiting for hydrogen production. We then increased hydrogen production by blocking alternative electron-utilizing metabolic pathways by mutagenesis. In addition we found that use of non-growing cells as biocatalysts for hydrogen gas production is an attractive option, because cells divert all resources away from growth and to hydrogen. Also R. palustris cells remain viable in a non-growing state for long periods of time.« less

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

Gibson, John K.; de Jong, Wibe A.; van Stipdonk, Michael J.

In uranyl coordination complexes, UO 2(L) n 2+, uranium in the formally dipositive [O=U=O] 2+ moiety is coordinated by n neutral organic electron donor ligands, L. The extent of ligand electron donation, which results in partial reduction of uranyl and weakening of the U=O bonds, is revealed by the magnitude of the red-shift of the uranyl asymmetric stretch frequency, ν 3 . This phenomenon appears in gas-phase complexes in which uranyl is coordinated by electron donor ligands: the ν 3 red-shift increases as the number of ligands and their proton affinity (PA) increases. Because PA is a measure of themore » enthalpy change associated with a proton-ligand interaction, which is much stronger and of a different nature than metal ion-ligand bonding, it is not necessarily expected that ligand PAs should reliably predict uranyl-ligand bonding and the resulting ν 3 red-shift. In this study, ν 3 was measured for uranyl coordinated by ligands with a relatively broad range of PAs, revealing a surprisingly good correlation between PA and ν 3 frequency. From computed ν 3 frequencies for bare UO 2 cations and neutrals, it is inferred that the effective charge of uranyl in UO 2(L) n 2+ complexes can be reduced to near zero upon ligation by sufficiently strong charge-donor ligands. The basis for the correlation between ν 3 and ligand PAs, as well as limitations and deviations from it, are considered. It is demonstrated that the correlation evidently extends to a ligand that exhibits polydentate metal ion coordination.« less

A theoretical investigation on Cu/Ag/Au bonding in XH2P⋯MY(X = H, CH3, F, CN, NO2; M = Cu, Ag, Au; Y = F, Cl, Br, I) complexes

NASA Astrophysics Data System (ADS)

Wang, Zhaoxu; Liu, Yi; Zheng, Baishu; Zhou, Fengxiang; Jiao, Yinchun; Liu, Yuan; Ding, XunLei; Lu, Tian

2018-05-01

Intermolecular interaction of XH2P...MY (X = H, CH3, F, CN, NO2; M = Cu, Ag, Au; Y = F, Cl, Br, I) complexes was investigated by means of an ab initio method. The molecular interaction energies are in the order Ag < Cu < Au and increased with the decrease of RP...M. Interaction energies are strengthened when electron-donating substituents X connected to XH2P, while electron-withdrawing substituents produce the opposite effect. The strongest P...M bond was found in CH3H2P...AuF with -70.95 kcal/mol, while the weakest one was found in NO2H2P...AgI with -20.45 kcal/mol. The three-center/four-electron (3c/4e) resonance-type of P:-M-:Y hyperbond was recognized by the natural resonance theory and the natural bond orbital analysis. The competition of P:M-Y ↔ P-M:Y resonance structures mainly arises from hyperconjugation interactions; the bond order of bP-M and bM-Y is in line with the conservation of the idealized relationship bP-M + bM-Y ≈ 1. In all MF-containing complexes, P-M:F resonance accounted for a larger proportion which leads to the covalent characters for partial ionicity of MF. The interaction energies of these Cu/Ag/Au complexes are basically above the characteristic values of the halogen-bond complexes and close to the observed strong hydrogen bonds in ionic hydrogen-bonded species.

Profile of Heart Donors from the Human Valve Bank of the Santa Casa de Misericórdia de Curitiba

PubMed Central

Ferreira, Renata Maria; da Costa, Marise Teresinha Brenner Affonso; Canciglieri Junior, Osiris; Sant'Anna, Ângelo Márcio Oliveira

2016-01-01

Introduction Human heart valves are used as replacement valves and have satisfactory functional results compared with conventional prostheses. Objective Characterize the profile of effective heart donors from the human valve bank of the santa casa de misericórdia de curitiba and analyze the association between the profile variables. Methods It consists of a retrospective and quantitative study of electronic medical records from heart donors for heart valves. every heart donation made to the bank between january 2004 and december 2014 was studied. Results 2,149 donations were analyzed, from donors aged 0 to 71 years old, with an average of 34.9 ± 15.03 years old. most donors were male 65.7% (n=1,411) and 34.3% (n=738) were female. among the most frequent causes of the donors' death are trauma at 53% (n=1,139) and cerebral vascular accident at 34.2% (n=735). there was significant statistical association between the analyzed variables. Conclusion There has been an improvement in brazil's donation rate, being essential that the tissue banks work together with the state and federal district centers for notification, procurement and distribution of organs in order to increase the number of donors. PMID:27556322

Evolution of deceased organ donation activity vs. efficiency over a 15 year period: an international comparison.

PubMed

Weiss, Julius; Elmer, Andreas; Mahíllo, Beatriz; Domínguez-Gil, Beatriz; Avsec, Danica; Costa, Alessandro Nanni; Haase-Kromwijk, Bernadette J J M; Laouabdia, Karim; Immer, Franz F

2018-04-19

The donation rate (DR) per million population is not ideal for an efficiency comparison of national deceased organ donation programs. The DR does not account for variabilities in the potential for deceased donation which mainly depends on fatalities from causes leading to brain death. In this study, the donation activity was put into relation to the mortality from selected causes. Based on that metric, this study assesses the efficiency of different donation programs. This is a retrospective analysis of 2001-2015 deceased organ donation and mortality registry data. Included are 27 Council of Europe countries, as well as the USA. A donor conversion index (DCI) was calculated for assessing donation program efficiency over time and in international comparisons. According to the DCI and of the countries included in the study, Spain, France, and the USA had the most efficient donation programs in 2015. Even though mortality from the selected causes decreased in most countries during the study period, differences in international comparisons persist. This indicates that the potential for deceased organ donation and its conversion into actual donation is far from being similar internationally. Compared with the DR, the DCI takes into account the potential for deceased organ donation, and therefore is a more accurate metric of performance. National donation programs could optimize performance by identifying the areas where most potential is lost, and by implementing measures to tackle these issues.

Subsequent donation requests among 2472 unrelated hematopoietic progenitor cell donors are associated with bone marrow harvest

PubMed Central

Lown, Robert N.; Tulpule, Sameer; Russell, Nigel H.; Craddock, Charles F.; Roest, Rochelle; Madrigal, J. Alejandro; Shaw, Bronwen E.

2013-01-01

Approximately 1 in 20 unrelated donors are asked to make a second donation of hematopoietic progenitor cells, the majority for the same patient. Anthony Nolan undertook a study of subsequent hematopoietic progenitor cell donations made by its donors from 2005 to 2011, with the aims of predicting those donors more likely to be called for a second donation, assessing rates of serious adverse reactions and examining harvest yields. This was not a study of factors predictive of second allografts. During the study period 2591 donations were made, of which 120 (4.6%) were subsequent donations. The median time between donations was 179 days (range, 21–4016). Indications for a second allogeneic transplant included primary graft failure (11.7%), secondary graft failure (53.2%), relapse (30.6%) and others (1.8%). On multivariate analysis, bone marrow harvest at first donation was associated with subsequent donation requests (odds ratio 2.00, P=0.001). The rate of serious adverse reactions in donors making a subsequent donation appeared greater than the rate in those making a first donation (relative risk=3.29, P=0.005). Harvest yields per kilogram recipient body weight were equivalent between donations, although females appeared to have a lower yield at the subsequent donation. Knowledge of these factors will help unrelated donor registries to counsel their donors. PMID:23812935

Blue emitting 1,8-naphthalimides with electron transport properties for organic light emitting diode applications

NASA Astrophysics Data System (ADS)

Ulla, Hidayath; Kiran, M. Raveendra; Garudachari, B.; Ahipa, T. N.; Tarafder, Kartick; Adhikari, Airody Vasudeva; Umesh, G.; Satyanarayan, M. N.

2017-09-01

In this article, the synthesis, characterization and use of two novel naphthalimides as electron-transporting emitter materials for organic light emitting diode (OLED) applications are reported. The molecules were obtained by substituting electron donating chloro-phenoxy group at the C-4 position. A detailed optical, thermal, electrochemical and related properties were systematically studied. Furthermore, theoretical calculations (DFT) were performed to get a better understanding of the electronic structures. The synthesized molecules were used as electron transporters and emitters in OLEDs with three different device configurations. The devices with the molecules showed blue emission with efficiencies of 1.89 cdA-1, 0.98 lmW-1, 0.71% at 100 cdm-2. The phosphorescent devices with naphthalimides as electron transport materials displayed better performance in comparison to the device without any electron transporting material and were analogous with the device using standard electron transporting material, Alq3. The results demonstrate that the naphthalimides could play a significant part in the progress of OLEDs.

Risk factors for complications in donors at first and repeat whole blood donation: a cohort study with assessment of the impact on donor return.

PubMed

Wiersum-Osselton, Johanna C; Marijt-van der Kreek, Tanneke; Brand, Anneke; Veldhuizen, Ingrid; van der Bom, Johanna G; de Kort, Wim

2014-01-01

First-time donation is among recognised risk factors for vasovagal reactions to blood donation and reactions are known to reduce donor return. We assessed associations between potential risk factors and vasovagal reactions and needle-related complications in first-time whole blood donation in comparison to repeat donation and analysed the impact of complications on donor return. We performed a cohort study on whole blood donations in The Netherlands from 1/1/2010 to 31/12/2010 using data extracted from the blood service information system. Donation data up to 31/12/2011 were used to ascertain donor return. In 2010 28,786 donors made first whole blood donations and there were 522,958 repeat donations. Vasovagal reactions occurred in 3.9% of first donations by males and 3.5% of first donations by females compared to in 0.2% and 0.6%, respectively, of repeat donations. Associations of vasovagal reactions with other factors including age, body weight, systolic and diastolic blood pressure were similar in first-time and repeat donors. Needle-related complications occurred in 0.2% of male and 0.5% of female first-time donations and in 0.1% and 0.3%, respectively, of repeat donations. Among first-time donors, the return rate within 1 year was 82% following an uncomplicated first donation, but 55% and 61% following vasovagal reactions and needle-related complications, respectively; the corresponding percentages among repeat donors were 86%, 58% and 82%. Among first-time donors, females suffered less than males from vasovagal reactions. Other risk factors had similar associations among first-time and repeat donors. Vasovagal reactions and needle-related complications in both first-time and repeat donors are followed by reduced donor return.

Donor Experiences of Second Marrow or Peripheral Blood Stem Cell Collection Mirror the First, but CD34+ Yields Are Less.

PubMed

Stroncek, David F; Shaw, Bronwen E; Logan, Brent R; Kiefer, Deidre M; Savani, Bipin N; Anderlini, Paolo; Bredeson, Christopher N; Hematti, Peiman; Ganguly, Siddhartha; Diaz, Miguel Angel; Abdel-Azim, Hisham; Ahmed, Ibrahim; Maharaj, Dipnarine; Seftel, Matthew; Beitinjaneh, Amer; Seo, Sachiko; Yared, Jean A; Halter, Joerg; O'Donnell, Paul V; Hale, Gregory A; DeFilipp, Zachariah; Lazarus, Hillard; Liesveld, Jane L; Zhou, Zheng; Munshi, Pashna; Olsson, Richard F; Kasow, Kimberly Anne; Szer, Jeffrey; Switzer, Galen E; Chitphakdithai, Pintip; Shah, Nirali; Confer, Dennis L; Pulsipher, Michael A

2018-01-01

Little is known about the experiences of individuals donating peripheral blood stem cells (PBSCs) or marrow for a second time. To study this, unrelated donors making a second donation through the National Marrow Donor Program between 2004 and 2013 were evaluated. Experiences of second-time donors giving marrow (n = 118: first donation was PBSC in 76 and marrow in 42) were compared with those making only 1 marrow donation (n = 5829). Experiences of second-time donors giving PBSCs (n = 602) (first donation was PBSCs in 362; marrow in 240) were compared to first-time PBSC donors (n = 16,095). For donors giving a second PBSC or marrow donation there were no significant differences in maximum skeletal pain, maximum symptoms measured by an established modified toxicity criteria, and recovery time compared with those who donated only once. Notably, the yield of marrow nucleated cells and PBSC CD34 + cells with second donations was less. As previously noted with single first-time donations, female (PBSCs and marrow) and obese donors (PBSCs) had higher skeletal pain and/or toxicity with a second donation. PBSC donors who experienced high levels of pain or toxicity with the first donation also experienced high levels of these symptoms with their second donation and slower recovery times. In conclusion, for most donors second donation experiences were similar to first donation experiences, but CD34 + yields were less. Knowledge of the donor's first experience and stem cell yields may help centers decide whether second donations are appropriate and institute measures to improve donor experiences. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

[Can one authorize oocyte donation in the Grand Duchy of Luxembourg?].

PubMed

Arendt, J

2012-01-01

In the case of early ovary extinction, the only way to have a child is either adoption or egg/embryo reception by donation. To day, egg donation is prohibited in Luxembourg by ministerial decision in 2003. Germ cell donation is part of artificial reproductive therapy. Oocyte donation, in particular, needs to be done by IVF treatment, which makes it more complicated then sperm donation What makes it more difficult is the fact that there are no oocyte bank yet. Today, prohibition encourages procreative tourism what only wealthy people can afford. Although donation programs are well established many questions arise about egg donation such as refunds, divulging information, women's age limit, health insurance participation.

When do next-of-kin opt-in? Anticipated regret, affective attitudes and donating deceased family member's organs.

PubMed

Shepherd, Lee; O'Carroll, Ronan E

2014-12-01

This research assessed whether affective factors promote and prevent family members from donating their loved one's organs. Participants (N = 191) imagined that a family member had died and that they had to decide whether or not to donate their organs and body parts for transplantation purposes. The least organs and body parts were donated when the deceased opposed donation. Moreover, participants who were not registered organ donors donated fewer organs than registered donors. This effect was mediated by anticipated regret, disgust and the perceived benefits of donation. Organ donation campaigns should target such factors to increase donor rates. © The Author(s) 2013.

Mass media, online social network, and organ donation: old mistakes and new perspectives.

PubMed

Aykas, A; Uslu, A; Şimşek, C

2015-05-01

Contrary to TV programs projecting awareness about organ donation in society, concrete evidence exists about adverse influence of negative broadcasts on organ donation rates. We sought to determine the effect of mass media on public opinion toward organ donation and the efficacy of public campaigns and novel social media attempts on donation rates. We conducted a systematic review of relevant literature and national campaign results. Hoaxes about brain death and organ transplantation adversely affect organ donation rates in both Western and Eastern societies. Scientifically controversial and exaggerated press conferences and institutional advertisements create mistrust in doctors, thus reducing organ donation. The overall effect of public education campaigns in promoting organ donation is a temporary 5% gain. Increments in organ donation rates is expected with novel applications of social media (Facebook effect). Communication, based on mutual trust, must be established between medicine and the media. Continuing education programs with regard to public awareness on organ donation should be conducted over social media. Copyright © 2015 Elsevier Inc. All rights reserved.

Investigation of the Redox Chemistry of Anthraquinone Derivatives Using Density Functional Theory

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

Bachman, Jonathan E.; Curtiss, Larry A.; Assary, Rajeev S.

2014-09-25

Application of density functional calculations to compute electrochemical properties such as redox windows, effect of substitution by electron donating and electron withdrawing groups on redox windows, and solvation free energies for ~50 anthraquinone (AQ) derivatives are presented because of their potential as anolytes in all-organic redox flow batteries. Computations suggest that lithium ions can increase (by ~0.4 V) the reduction potential of anthraquinone due to the lithium ion pairing by forming a Lewis base-Lewis acid complex. To design new redox active species, the substitution by electron donating groups are essential to improve the reduction window of AQ with adequate oxidativemore » stability. For instance, a complete methylation of AQ can improve its reduction window by ~0.4 V. The quantum chemical studies of the ~50 AQ derivatives are used to derive a relationship that connects the computed LUMO energy and the reduction potential that can be applied as a descriptor for screening thousands of AQ derivatives. Our computations also suggest that incorporating oxy-methyl dioxolane substituents in the AQ framework can increase its interaction with non-aqueous solvent and improve its solubility. Thermochemical calculations for likely bond breaking decomposition reactions of un-substituted AQ anions suggest that the dianions are relatively stable in the solution. These studies provide ideal platform to perform further combined experimental and theoretical studies to understand the electrochemical reversibility and solubility of new quinone molecules as energy storage materials.« less

Monodentate phosphine substitution in [Pd(κ3-dppf)(PR3)][BF4]2 (dppf = 1,1'-bis(diphenylphosphino)ferrocene) compounds.

PubMed

Cabrera, K D; Rowland, A T; Szarko, J M; Diaconescu, P L; Bezpalko, M W; Kassel, W S; Nataro, C

2017-05-02

The ligand 1,1'-bis(diphenylphosphino)ferrocene (dppf) is commonly employed in a variety of catalytic systems. There are a variety of coordination modes known for dppf, the least studied being the κ 3 coordination mode, in which both phosphorus atoms and the iron atom of dppf interact with another metal center. One such compound is the previously reported [Pd(κ 3 -dppf)(PPh 3 )] 2+ . A series of related compounds, [Pd(κ 3 -dppf)(P(p-C 6 H 4 R) 3 )] 2+ (R = OCH 3 , CH 3 , F and CF 3 ), has been synthesized and characterized. The X-ray crystal structure of [Pd(dppf)(P(p-C 6 H 4 F) 3 )][BF 4 ] 2 was determined. Electrochemical and computational studies indicate that the electron donor ability of the P(p-C 6 H 4 R) 3 ligands influences the properties of these compounds. Substitution reactions of the P(p-C 6 H 4 R) 3 ligands have been examined, and, in general, the more electron donating P(p-C 6 H 4 R) 3 ligands completely replace the less electron donating ones. The kinetics of the reaction of [Pd(κ 3 -dppf)(P(p-C 6 H 4 F) 3 )] 2+ with P(p-C 6 H 4 OCH 3 ) 3 indicate that the reaction proceeds through a dissociative mechanism, contrary to the associative substitutions prevalent in square planar palladium(ii) chemistry.

Knowledge, Attitudes, and Motivations towards Blood Donation among King Abdulaziz Medical City Population.

PubMed

Alfouzan, Najd

2014-01-01

Background. Blood donation is remarkably safe medical procedure. However, attitudes, beliefs, and level of knowledge may affect it. Objectives. To measure the level of knowledge regarding blood donation, find out positive and negative attitudes, identify the obstacles, and suggest some motivational factors. Methodology. A cross-sectional study was conducted at King Abdulaziz Medical City (KAMC). Participants were selected by convenient nonrandom sampling technique. A self-created questionnaire was used for data collection. Results. The study included 349 individuals. About 45.8% of the participants claimed that they have a history of blood donation. Reported causes for not donating blood were blood donation not crossing their mind (52.4%), no time for donation (45%), and difficulty in accessing blood donation center (41.3%). Reported motivating factors for donating blood were one day off (81.4%), mobile blood donation caravans in public areas (79.1%), token gifts (31.5%), and finally paying money (18.9%). Conclusion. People in the age group 31-50 years, males, higher education and military were more likely to donate blood as well as People who showed higher knowledge level and positive attitude towards blood donation. More educational programs to increase the awareness in specific targeted populations and also to focus on some motivational factors are recommended.

Knowledge, Attitudes, and Motivations towards Blood Donation among King Abdulaziz Medical City Population

PubMed Central

2014-01-01

Background. Blood donation is remarkably safe medical procedure. However, attitudes, beliefs, and level of knowledge may affect it. Objectives. To measure the level of knowledge regarding blood donation, find out positive and negative attitudes, identify the obstacles, and suggest some motivational factors. Methodology. A cross-sectional study was conducted at King Abdulaziz Medical City (KAMC). Participants were selected by convenient nonrandom sampling technique. A self-created questionnaire was used for data collection. Results. The study included 349 individuals. About 45.8% of the participants claimed that they have a history of blood donation. Reported causes for not donating blood were blood donation not crossing their mind (52.4%), no time for donation (45%), and difficulty in accessing blood donation center (41.3%). Reported motivating factors for donating blood were one day off (81.4%), mobile blood donation caravans in public areas (79.1%), token gifts (31.5%), and finally paying money (18.9%). Conclusion. People in the age group 31–50 years, males, higher education and military were more likely to donate blood as well as People who showed higher knowledge level and positive attitude towards blood donation. More educational programs to increase the awareness in specific targeted populations and also to focus on some motivational factors are recommended. PMID:25431668

Organ donation education initiatives: A report of the Donor Management Task Force.

PubMed

Michetti, Christopher P; Nakagawa, Thomas A; Malinoski, Darren; Wright, Charles; Swanson, LeAnn

2016-10-01

It is essential that hospitals and health professionals establish systems to facilitate patients' organ donation wishes. Donation education has been neither standardized nor systematic, and resources related to donation processes have not been widely accessible. This report describes 2 free, publicly available educational resources about the organ donation process created to advance the mission of basic education and improve donation processes within hospitals and health care systems. Members of the Donor Management Task Force of the Organ Donation and Transplantation Alliance (the Alliance) and the Health Resources and Services Administration of the US Department of Health and Human Services convened annually in person and by teleconferencing during the year to develop 2 educational vehicles on organ donation. Two educational products were developed: the Organ Donation Toolbox, an online repository of documents and resources covering all aspects of the donation process, and the Educational Training Video that reviews the basic foundations of a successful hospital donation system. There is a need for more research and education about the process of organ donation as it relates to the medical and psychosocial care of patients and families before the end of life. The educational products described can help fill this critical need. Copyright © 2016 Elsevier Inc. All rights reserved.

Understanding the Role of Clergy in African American Organ and Tissue Donation Decision-Making

PubMed Central

Jacob Arriola, Kimberly R.; Perryman, Jennie P.; Doldren, Michelle A.; Warren, Carmen M.; Robinson, Dana H. Z.

2012-01-01

Objectives To describe and understand the attitudes, beliefs, and experiences towards organ and tissue donation among African American clergy in Atlanta, Georgia, USA. The secondary objective is to understand what messages clergy are providing to their parishioners relative to organ and tissue donation, and what their perceived role is in donation education. Design A qualitative study in which African American clergy (n = 26) participated in four focus groups. Results African American clergy, though generally supportive of organ and tissue donation in principle, have serious reservations about donation due to perceived inequalities in the donation and transplantation system. The clergy did not personally hold religious concerns about donation, but expressed that these concerns were a major barrier to donation among their parishioners. None of the clergy knew the written position that their religion took on donation; they acknowledged the need for more education for them and their parishioners on this topic. They also felt that as religious leaders, they could play an important role in promoting organ and tissue donation among African American parishioners. Conclusions African American clergy and religious leaders may play an important role towards improving willingness to donate among African American parishioners, but more education and advocacy is needed to prepare them for this role. PMID:17978944

Trend Analysis of Organ and Tissue Donation for Transplantation.

PubMed

Dos Santos, M J; Leal de Moraes, E; Santini Martins, M; Carlos de Almeida, E; Borges de Barros E Silva, L; Urias, V; Silvano Corrêa Pacheco Furtado, M C; Brito Nunes, Á; El Hage, S

2018-03-01

The goal of this study was to identify the tendency toward donations of tissue and organs from donors with brain death between 2001 and 2016 as registered by an organ procurement organization in São Paulo City. This quantitative, retrospective, exploratory study encompassed all Tissue and Organ Donation Terms signed between 2001 and 2016. A logistic regression model was applied to verify whether there was an upward or downward trend in donation. After statistical analysis, a significant change trend was identified in skin, bones, valve, vessel, heart, lung, and pancreas donations, indicating an increase in the donation rate through the years. The donation rate did not show changes over the years for donations of liver, kidneys, and corneas. The decision-making process regarding organ and tissue donation is restricted not only to the dilemma of whether to donate but another question then arises as well: which organs and tissues are to be donated? The discrepancy between the authorization for organ donation and the authorization for tissue donation, as well as the option for one or another organ and/or tissue, must be thoroughly examined because these factors directly affect the number of transplants and acquirements effectively accomplished. These factors may be related to explaining to one's relatives aspects of the surgery, body reassembling, and usage of such organs and/or tissues. They may also be related to the lack of knowledge concerning organ donation and the symbolism represented by the organ and/or tissue, among other factors. Copyright © 2018 Elsevier Inc. All rights reserved.

Public Opinion on Organ Donation After Death and Its Influence on Attitudes Toward Organ Donation.

PubMed

Aijing, Luo; Wenzhao, Xie; Wei, Wei; Qiquan, Wan; Xuantong, Deng

2016-08-18

BACKGROUND China officially launched a pilot program of organ donation after cardiac death to overcome the shortage of available organs since 2011. Voluntary organ donation by deceased citizens became the only source of transplant organs beginning January 1, 2015. To investigate public opinions on organ donation by deceased donors, and discuss the effect of these opinions on the willingness and attitude of the public regarding voluntary organ donation. MATERIAL AND METHODS We designed a questionnaire. The survey was conducted from December 2014 to January 2015 in Changsha City, and 417 valid questionnaires were recovered. RESULTS A total of 162 respondents explicitly expressed a willingness to donate organs, and 269 believed that the organ donors' relatives should be compensated. A total of 255 respondents thought it acceptable to complete the donation-consent form when receiving a driver's license. Among the respondents, 65.3% did not agree with the statement "My body is bestowed by my parents, and to donate my body parts would not display filial respect"; 88.9% agreed that "It is necessary to consider the willingness of my family"; 74.4% agreed that "Donated organs have not been fairly and appropriately used; the wealthy and celebrities have been favored"; and 61.4% agreed that "Organ donation laws and regulations are not well developed, and organ donations will result in unnecessary difficulties." More than 80% believed that organ donation and transplantation extend life. CONCLUSIONS Public opinions on organ donation after death are associated with various factors, including traditional values, religious beliefs, compensation mechanisms, donor registration, institutional credibility, and ideals.

Can family or replacement blood donors become regular volunteer donors?

PubMed

Asenso-Mensah, Kwame; Achina, Gifty; Appiah, Rita; Owusu-Ofori, Shirley; Allain, Jean-Pierre

2014-03-01

In sub-Saharan Africa (SSA) confirmed viral marker prevalence between family donors (FDs) and first-time volunteer nonremunerated donors (VNRDs) is similar. In a blood service collecting 10 units/1000 inhabitants, a questionnaire examined FD donation conditions and willingness of becoming repeat VNRDs. Four areas were explored: circumstances of visit to hospital, external pressure, experience of donating, and potential repeat donation. After donation and consent, research assistants administered 25 questions and, according to literacy, helped with translation and completion. Of 513 FDs, three-fourths were males (median age, 27 years). Only 1.3% were unemployed and more than 50% were students or teachers. Ties with hospitalized patient were family (76%), friends (13%), colleagues, or sharing place of worship (10%). Donating blood was the reason for visiting in 16.8% and 20.9% had previously donated blood probably as FDs. In one-third of FDs, the family asked for donation of which 10% was pressured by the unjustified reason that not donating was endangering the patient's life. For two-thirds of FDs, donation was given "because individuals were asked." Donation was a positive experience for 77% of donors, 62% being interested in predonation testing. Repeating donation was acceptable for 99% of 79% FDs answering. FDs are active in the population, are willing to donate blood if asked, are submitted to little pressure, do not receive incentives, and accept repeat donation. Except for circumstances of donation, FDs are not different from VNRDs and more directly motivated. They constitute a legitimate and important source to improve the blood supply in SSA. © 2013 American Association of Blood Banks.

The value of area-based analyses of donation patterns for recruitment strategies.

PubMed

James, Adelbert B; Josephson, Cassandra D; Shaz, Beth H; Schreiber, George B; Hillyer, Christopher D; Roback, John D

2014-12-01

Lack of ready access to a donation site may be a potential barrier to or influence the frequency of blood donations. In this study, we applied geographic analysis to blood donor behavior and use of different donation sites. The study population consisted of blood donors who gave whole blood in Georgia between 2004 and 2008. Zip code, city, and county of donor's residence were matched with the addresses of their donation sites. Donors were dichotomized as either nonmetro Atlanta or metro Atlanta residents. Six donation site categories were defined: donation within the same or a different zip code, within the same or a different city, and within the same or a different county. Logistic regression was used to compare donations by zip code, city, and county. The study population consisted of 402,692 blood donors who donated 1,147,442 whole blood units between 2004 and 2008, more than half of whom (56.4%) resided in the metro Atlanta area. The majority of donors were white (75.0%) and female (55.7%). In nonmetro Atlanta, repeat donors were more likely to have donated at fixed sites (p < 0.001). In metro Atlanta, repeat donors were more likely to have donated at a mobile site than at a fixed site (p < 0.001). Geographic and demographic differences in blood donation patterns exist. The locations of donor residences and blood donation sites influence donor behaviors. Understanding the geographic influence on donation patterns provides an important tool for optimizing donor recruitment strategies. © 2014 AABB.

Relationship between x-ray emission and absorption spectroscopy and the local H-bond environment in water

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

Zhovtobriukh, Iurii; Besley, Nicholas A.; Fransson, Thomas

Here, the connection between specific features in the water X-ray absorption spectrum and X-ray emission spectrum (XES) and the local H-bond coordination is studied based on structures obtained from path-integral molecular dynamics simulations using either the opt-PBE-vdW density functional or the MB-pol force field. Computing the XES spectrum using all molecules in a snapshot results in only one peak in the lone-pair (1b 1) region, while the experiment shows two peaks separated by 0.8-0.9 eV. Different H-bond configurations were classified based on the local structure index (LSI) and a geometrical H-bond cone criterion. We find that tetrahedrally coordinated molecules characterizedmore » by high LSI values and two strong donated and two strong accepted H-bonds contribute to the low energy 1b 1 emission peak and to the post-edge region in absorption. Molecules with the asymmetric H-bond environment with one strong accepted H-bond and one strong donated H-bond and low LSI values give rise to the high energy 1b 1 peak in the emission spectrum and mainly contribute to the pre-edge and main-edge in the absorption spectrum. The 1b 1 peak splitting can be increased to 0.62 eV by imposing constraints on the H-bond length, i.e., for very tetrahedral structures short H-bonds (less than 2.68 Å) and for very asymmetric structures elongated H-bonds (longer than 2.8 Å). Such structures are present, but underrepresented, in the simulations which give more of an average of the two extremes.« less

Relationship between x-ray emission and absorption spectroscopy and the local H-bond environment in water

DOE PAGES

Zhovtobriukh, Iurii; Besley, Nicholas A.; Fransson, Thomas; ...

2018-04-14

Here, the connection between specific features in the water X-ray absorption spectrum and X-ray emission spectrum (XES) and the local H-bond coordination is studied based on structures obtained from path-integral molecular dynamics simulations using either the opt-PBE-vdW density functional or the MB-pol force field. Computing the XES spectrum using all molecules in a snapshot results in only one peak in the lone-pair (1b 1) region, while the experiment shows two peaks separated by 0.8-0.9 eV. Different H-bond configurations were classified based on the local structure index (LSI) and a geometrical H-bond cone criterion. We find that tetrahedrally coordinated molecules characterizedmore » by high LSI values and two strong donated and two strong accepted H-bonds contribute to the low energy 1b 1 emission peak and to the post-edge region in absorption. Molecules with the asymmetric H-bond environment with one strong accepted H-bond and one strong donated H-bond and low LSI values give rise to the high energy 1b 1 peak in the emission spectrum and mainly contribute to the pre-edge and main-edge in the absorption spectrum. The 1b 1 peak splitting can be increased to 0.62 eV by imposing constraints on the H-bond length, i.e., for very tetrahedral structures short H-bonds (less than 2.68 Å) and for very asymmetric structures elongated H-bonds (longer than 2.8 Å). Such structures are present, but underrepresented, in the simulations which give more of an average of the two extremes.« less

48 CFR 45.603 - Abandonment, destruction or donation of excess personal property.

Code of Federal Regulations, 2010 CFR

2010-10-01

... or donation of excess personal property. 45.603 Section 45.603 Federal Acquisition Regulations System... Disposal 45.603 Abandonment, destruction or donation of excess personal property. (a) Plant clearance... any of the costs incident to a donation. (d)(1) Before abandoning, destroying, or donating excess...

23 CFR 710.505 - Real property donations.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Real property donations. 710.505 Section 710.505...-WAY AND REAL ESTATE Property Acquisition Alternatives § 710.505 Real property donations. (a) Donations..., whichever is greater. All donations of property received prior to the approval of the NEPA document must...

48 CFR 45.604-2 - Abandonment, destruction, or donation of surplus property.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., or donation of surplus property. 45.604-2 Section 45.604-2 Federal Acquisition Regulations System... Disposal 45.604-2 Abandonment, destruction, or donation of surplus property. (a) Plant clearance officers... the costs incident to donation. (d) Before abandoning, destroying, or donating surplus property, the...

32 CFR 553.6 - Donations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 3 2010-07-01 2010-07-01 true Donations. 553.6 Section 553.6 National Defense... NATIONAL CEMETERIES § 553.6 Donations. (a) Policy. Under Department of the Army policy, proffered donations... for the donation or gift. (2) Delivery is made to the cemetery or to another point designated by the...

41 CFR 101-42.304 - Special requirements for donation of certain hazardous materials.

Code of Federal Regulations, 2010 CFR

2010-07-01

... donation of certain hazardous materials. 101-42.304 Section 101-42.304 Public Contracts and Property....3-Donation of Hazardous Materials and Certain Categories of Property § 101-42.304 Special requirements for donation of certain hazardous materials. Special donation requirements for specific hazardous...

41 CFR 101-42.304 - Special requirements for donation of certain hazardous materials.

Code of Federal Regulations, 2012 CFR

2012-07-01

... donation of certain hazardous materials. 101-42.304 Section 101-42.304 Public Contracts and Property....3-Donation of Hazardous Materials and Certain Categories of Property § 101-42.304 Special requirements for donation of certain hazardous materials. Special donation requirements for specific hazardous...

48 CFR 45.603 - Abandonment, destruction or donation of excess personal property.

Code of Federal Regulations, 2011 CFR

2011-10-01

... or donation of excess personal property. 45.603 Section 45.603 Federal Acquisition Regulations System... Disposal 45.603 Abandonment, destruction or donation of excess personal property. (a) Plant clearance... any of the costs incident to a donation. (d)(1) Before abandoning, destroying, or donating excess...

41 CFR 101-42.304 - Special requirements for donation of certain hazardous materials.

Code of Federal Regulations, 2013 CFR

2013-07-01

... donation of certain hazardous materials. 101-42.304 Section 101-42.304 Public Contracts and Property....3-Donation of Hazardous Materials and Certain Categories of Property § 101-42.304 Special requirements for donation of certain hazardous materials. Special donation requirements for specific hazardous...

32 CFR 553.6 - Donations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 3 2011-07-01 2009-07-01 true Donations. 553.6 Section 553.6 National Defense... NATIONAL CEMETERIES § 553.6 Donations. (a) Policy. Under Department of the Army policy, proffered donations... for the donation or gift. (2) Delivery is made to the cemetery or to another point designated by the...

2 CFR 200.434 - Contributions and donations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 2 Grants and Agreements 1 2014-01-01 2014-01-01 false Contributions and donations. 200.434 Section... Cost § 200.434 Contributions and donations. (a) Costs of contributions and donations, including cash... space is not reimbursable either as a direct or indirect cost. (2) The value of the donations may be...

48 CFR 45.604-2 - Abandonment, destruction, or donation of surplus property.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., or donation of surplus property. 45.604-2 Section 45.604-2 Federal Acquisition Regulations System... Disposal 45.604-2 Abandonment, destruction, or donation of surplus property. (a) Plant clearance officers... the costs incident to donation. (d) Before abandoning, destroying, or donating surplus property, the...

41 CFR 101-42.304 - Special requirements for donation of certain hazardous materials.

Code of Federal Regulations, 2014 CFR

2014-07-01

... donation of certain hazardous materials. 101-42.304 Section 101-42.304 Public Contracts and Property....3-Donation of Hazardous Materials and Certain Categories of Property § 101-42.304 Special requirements for donation of certain hazardous materials. Special donation requirements for specific hazardous...

32 CFR 553.6 - Donations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 3 2013-07-01 2013-07-01 false Donations. 553.6 Section 553.6 National Defense... NATIONAL CEMETERIES § 553.6 Donations. (a) Policy. Under Department of the Army policy, proffered donations... for the donation or gift. (2) Delivery is made to the cemetery or to another point designated by the...

32 CFR 553.6 - Donations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 3 2012-07-01 2009-07-01 true Donations. 553.6 Section 553.6 National Defense... NATIONAL CEMETERIES § 553.6 Donations. (a) Policy. Under Department of the Army policy, proffered donations... for the donation or gift. (2) Delivery is made to the cemetery or to another point designated by the...

41 CFR 101-42.304 - Special requirements for donation of certain hazardous materials.

Code of Federal Regulations, 2011 CFR

2011-07-01

... donation of certain hazardous materials. 101-42.304 Section 101-42.304 Public Contracts and Property....3-Donation of Hazardous Materials and Certain Categories of Property § 101-42.304 Special requirements for donation of certain hazardous materials. Special donation requirements for specific hazardous...

Factors affecting Israeli women's decision whether to donate cord blood.

PubMed

Ben Natan, Merav; Grinberg, Keren; Galula, Sharon; Biton, Michal

2014-01-01

To examine whether Israeli mothers' intention to donate cord blood can be predicted using the Theory of Planned Behavior (TPB). A descriptive correlation study, employing the TPB. A questionnaire constructed based on a literature review of research on cord blood donation and on the TPB was administered to 207 Israeli women of childbearing age. Behavioral attitudes (women's total appraisal of cord blood donation), subjective norms (women's perception of the opinion of significant others regarding the specific behavior), and perceived behavioral control (women's total appraisal of their control of the behavior and perceived ease or difficulty of cord blood donation) were found to predict women's intention to donate cord blood. Since behavioral attitudes, subjective norms, and behavioral control can predict cord blood donations, it is important for the medical and nursing staff to understand and use these concepts if they hope to obtain women's cooperation concerning cord blood donation. Nurses should receive education on the subject of cord blood donation, increasing their awareness. It is possible that this could lead to a rise in such donations in the future. Both mothers and fathers should be consulted about the option of donating cord blood.

The challenges of social marketing of organ donation: news and entertainment coverage of donation and transplantation.

PubMed

Harrison, Tyler R; Morgan, Susan E; Chewning, Lisa V

2008-01-01

While great strides have been made in persuading the public to become potential organ donors, actual behavior has not yet caught up with the nearly universally favorable attitudes the public expresses toward donation. This paper explores the issue by situating the social marketing of organ donation against a broader backdrop of entertainment and news media coverage of organ donation. Organ donation storylines are featured on broadcast television in medical and legal dramas, soap operas, and other television serials approximately four times per month (not including most cable networks), and feature storylines that promote myths and fears of the organ donation process. National news and other non-fictionalized coverage of organ donation are even more common, with stories appearing over twenty times a month on average. These stories tend to be one-dimensional and highly sensationalized in their coverage. The marketing of organ donation for entertainment essentially creates a counter-campaign to organ donation, with greater resources and reach than social marketers have access to. Understanding the broader environmental context of organ donation messages highlights the issues faced by social marketing campaigns in persuading the public to become potential donors.

Knowledge and practice of blood donation: a comparison between medical and non-medical Nepalese students.

PubMed

Mamatya, A; Prajapati, R; Yadav, R

2012-12-01

College students form a large and important group of population eligible for blood donation. Studies report that students do not donate much, and medical students' blood donation rate is less as compared to non-medical students. To assess and compare the knowledge, attitude, and practice of blood donation among medical and non-medical Nepalese students. A cross-sectional descriptive study using structured self-administered questionnaire was conducted in students of medical (MBBS) and non-medical programs of different colleges of Nepal. Total 456 students, 177 non-medical and 279 medical, participated; 28.5% students were donors. More medical students donated blood, more often, and were more knowledgeable in all aspects of blood and blood donation related knowledge (p values 0.01 or less). In both groups, proportionately more boys donated than girls. Common reasons for not donating included no request, medically unfit, no information about blood collection services, fear of weakness, and fear related to venepuncture. Moral satisfaction was the commonest reason to donate. Among Nepalese students, medical students donate more and are more knowledgeable than non-medical students. Lack of information and lack of direct requests are important causes of fewer donors in the non-medical group and girls.

Awareness about organ donation especially kidney donation in Nurpur Shahan, a rural community area in Islamabad, Pakistan.

PubMed

Maroof, Sana; Kiyani, Nimrah; Zaman, Zahra; Gul, Raisa Khan; Nayyar, Sarah; Azmat, Ayesha; Anwar, Nageen; Shah, Rahim; Iqbal, Saima; Junaid, Aliya

2011-08-01

To assess the level of awareness and ethical issues related to organ donation especially kidney donation and the willingness to donate a kidney among the rural population of Pakistan. A cross sectional study was conducted in a sample of 324 subjects residing in Nurpur Shahan by means of a pre tested questionnaire. Data collection was carried out via a face to face interview and the data was analyzed using SPSS 10.0 and associations were tested using the Chi-square test. Knowledge about organ donation was significantly associated with age (p = 0.00) and education (p = 0.024). Allowance of organ donation in religion was an important factor in determining the attitude of individuals towards organ donation and their willingness to donate. Media emerged as a major source of information for the population of Nurpur Shahan; kidney was the organ most known for its donation. Most (69%) respondents did not consider organ vending to be ethically correct but a sizeable proportion (25%) thought it may be considered in times of dire need. Awareness of organ donation in our sample was high and more than half of the people were willing to become donors.

The rates, perceptions, and willingness of men who have sex with men to donate blood.

PubMed

Liszewski, Walter; Becerril, Jordan; Terndrup, Christopher; West, Nathan; Lavin, Bridget C; Schieffler, Danny; Van Sickels, Nicholas

2014-07-01

Since 1983 in the United States, any man who has had sex with another man (MSM) at any time since 1977 has been deferred from donating blood for life. Although there has been a push to change the deferral, there is a paucity of information on both the rates of MSM blood donation and the willingness of MSMs to donate if the deferral were changed. A 15-question survey was given at two lesbian, gay, bisexual, and transgender festivals in Chicago and New Orleans. Participants were asked about a previous history of blood donation and whether they would be willing to donate were the lifetime deferral changed. Participants were also asked to determine whether it was safe for hypothetical MSMs with varying sexual practices to donate blood and whether they believed that it was safe for them to donate their own blood. Our study found that 42.0% of all participants had not complied with the deferral policy and have donated blood at least once, with a mean number of donations of 4.84. Additionally, 85.9% of participants would be willing to donate blood if the deferral were changed. Despite the lifetime deferral, many MSMs have previously donated blood, and many more are willing to donate. Given this, along with the safe implementation of temporary deferral policies in other nations, the United States should consider adopting a temporary deferral policy for MSMs. © 2014 AABB.

Investigation and Strategic Analysis of Public Willingness and Attitudes Toward Organ Donation in East China.

PubMed

Zhang, H; Zheng, J; Liu, W; Ding, J; Zhang, L; Zhang, H; Zou, Y; Fu, Y

2015-10-01

China officially initiated deceased organ donation in 2010. Much progress has been made since then. However, compared with the developed countries in Europe and America, there is still a large gap. In this study, we investigate the willingness and attitude of the general public in East China and the factors that affect organ donation, and propose specific recommendations for promoting it. A simple and random sample was questioned. The data were analyzed statistically using SPSS 19.0 software, χ(2) test, and logistic regression. A total of 1200 questionnaires were issued; of these, 1105 were recovered, with 1074 effective questionnaires, for an effective rate of 89.5%. Among these, 426 respondents (39.7%) were willing to donate, 529 (49.3%) were in favor of donation but would not donate themselves; and 119 (11.1%) were against donation. Women (P < .01), persons with higher education (P < .01), those who understand organ donation (P < .01), and those who accept the concept of brain death (P < .01) had higher degrees of acceptance for organ donation. Reasons to hinder organ donation included imperfect laws and regulations, distrust on organ allocation, and insufficient promotion by relevant organizations. Much needs to be done to promote organ donation in China; targeted publicity will help to improve the work efficiency of organ donation; improvement of relevant policies and regulations, and establishment of a fair and transparent organ allocation system are key to the development of organ donation. Copyright © 2015 Elsevier Inc. All rights reserved.

Inappropriate drug donations: what has happened since the 1999 WHO guidelines?

PubMed

van Dijk, D P; Dinant, G; Jacobs, J A

2011-08-01

Drug donations to developing countries may be part of medical relief operations in acute emergencies, development aid in non-emergency situations, or a corporate donations programme. After a number of documented inappropriate drug donations, the World Health Organization developed the 'Guidelines for Drug Donations', with the second and final version published in 1999. We reviewed the medical literature on drug donations since the Guidelines publication in 1999. Literature was retrieved from PubMed and other on-line databases as well as from relevant websites providing medical literature for use in developing countries. We considered the following donations to be inappropriate: (i) essential drugs in excessive quantities; (ii) mixed unused drugs (unsorted medicines and free samples); and (iii) drug dumping (large quantities of useless medicines). We retrieved 25 publications dated after 1999, including 20 and 5 from the scientific literature and 'grey' literature (technical reports, working papers), respectively. New information concerned emergencies in East Timor, Mozambique, El Salvador, Gujarat State (India), Aceh (Indonesia) and Sri Lanka. Except for East Timor and Gujarat, inappropriate donations still occurred, accounting for 85%, 37%, 70% and 80% of donations in Mozambique, El Salvador, Aceh and Sri Lanka, respectively. Very little information was found on drug donations in non-emergency situations. There are few recent reports on the compliance of drug donations with the World Health Organization guidelines. For emergency situations, there is still room for improvement. Drug donations in non-emergency situations need to be evaluated. A reform of drug donations policy is needed.

Knowledge, attitude, and practice regarding voluntary blood donation among adult residents of Harar town, Eastern Ethiopia: a community-based study

PubMed Central

Urgesa, Kedir; Hassen, Nejat; Seyoum, Ayichew

2017-01-01

Background The availability of safe blood and blood products is a critical factor in improving health care. In Ethiopia, lack of voluntary blood donors is a major challenge. This could be due to low community knowledge, unfavorable attitude, and poor donation practice regarding voluntary blood donation. Thus, the aim of this study was to assess community knowledge, attitude, and practice regarding voluntary blood donation among adults in Harar town, Ethiopia. Materials and methods A community-based cross-sectional study was conducted from July 1 to July 31, 2015. A total of 845 adults were randomly selected and interviewed using a pretested, structured questionnaire. Six trained data collectors conducted a face-to-face interview. Data were entered into EpiData Version 3 and analyzed using STATA Version 11. Results Comprehensive knowledge of the study participants toward voluntary blood donation was 43.5%. Multivariable logistic regression demonstrated that male sex (adjusted odds ratio [AOR] = 1.69, 95% confidence interval [CI]: 1.19–2.39), age (31–45 years; AOR = 0.50, 95% CI: 0.34–0.74) and >45 years (AOR = 0.60, 95% CI: 0.38–0.95), and higher education (AOR = 15.34, 95% CI: 5.01–46.91) were significantly associated with comprehensive knowledge about voluntary blood donation. A total of 278 (32.9%) study participants had positive attitude toward voluntary blood donation. College graduates (AOR = 13.05, 95% CI: 4.12–41.29) were significantly associated with positive attitude toward voluntary blood donation. Only 191 (22.6%) subjects had ever donated blood. However, the proportion of study participants who donated blood voluntarily with good knowledge about voluntary blood donation was significantly lower than the study participants who donated blood voluntarily with low knowledge (X2 = 6.1746, P = 0.013). Conclusion This study showed an inauspicious attitude toward blood donation and poor blood donation practices. Subjects with good comprehensive knowledge about voluntary blood donation were less likely to donate blood voluntarily compared to those with lower comprehensive knowledge about voluntary blood donation. PMID:28243159

Knowledge, attitude, and practice regarding voluntary blood donation among adult residents of Harar town, Eastern Ethiopia: a community-based study.

PubMed

Urgesa, Kedir; Hassen, Nejat; Seyoum, Ayichew

2017-01-01

The availability of safe blood and blood products is a critical factor in improving health care. In Ethiopia, lack of voluntary blood donors is a major challenge. This could be due to low community knowledge, unfavorable attitude, and poor donation practice regarding voluntary blood donation. Thus, the aim of this study was to assess community knowledge, attitude, and practice regarding voluntary blood donation among adults in Harar town, Ethiopia. A community-based cross-sectional study was conducted from July 1 to July 31, 2015. A total of 845 adults were randomly selected and interviewed using a pretested, structured questionnaire. Six trained data collectors conducted a face-to-face interview. Data were entered into EpiData Version 3 and analyzed using STATA Version 11. Comprehensive knowledge of the study participants toward voluntary blood donation was 43.5%. Multivariable logistic regression demonstrated that male sex (adjusted odds ratio [AOR] = 1.69, 95% confidence interval [CI]: 1.19-2.39), age (31-45 years; AOR = 0.50, 95% CI: 0.34-0.74) and >45 years (AOR = 0.60, 95% CI: 0.38-0.95), and higher education (AOR = 15.34, 95% CI: 5.01-46.91) were significantly associated with comprehensive knowledge about voluntary blood donation. A total of 278 (32.9%) study participants had positive attitude toward voluntary blood donation. College graduates (AOR = 13.05, 95% CI: 4.12-41.29) were significantly associated with positive attitude toward voluntary blood donation. Only 191 (22.6%) subjects had ever donated blood. However, the proportion of study participants who donated blood voluntarily with good knowledge about voluntary blood donation was significantly lower than the study participants who donated blood voluntarily with low knowledge ( X 2 = 6.1746, P = 0.013). This study showed an inauspicious attitude toward blood donation and poor blood donation practices. Subjects with good comprehensive knowledge about voluntary blood donation were less likely to donate blood voluntarily compared to those with lower comprehensive knowledge about voluntary blood donation.

Does organ donation legislation affect individuals' willingness to donate their own or their relative's organs? Evidence from European Union survey data.

PubMed

Mossialos, Elias; Costa-Font, Joan; Rudisill, Caroline

2008-02-27

Maintaining adequately high organ donation rates proves essential to offering patients all appropriate and available treatment options. However, the act of donation is in itself an individual decision that requires a depth of understanding that interacts with the social setting and the institutional framework into which an individual is embedded. This study contributes to understanding factors driving organ donation rates by examining how country regulation, individuals' awareness of regulatory setting, social interactions and socio-demographic determinants influence individuals' willingness to donate their own organs or those of a relative. We draw representative data from the Eurobarometer survey 58.2 undertaken in 2002 with respondents throughout the European Union to capture heterogeneity in institutional setting. We use logistic regression techniques to estimate the determinants of willingness to donate one's own organs and those of a deceased relative. We employ interaction terms to examine the relationship between institutional setting and respondent's awareness of organ donation legislation in their country. Our findings indicate that individuals are more likely to donate their organs than to consent to the donation of a relative's organs. Both decisions are affected by regulation (presumed consent), awareness of regulation and social interactions such as the ability to count on others in case of a serious problem (reciprocity). Furthermore, education (more educated), age (younger), expressing some sort of political affiliation determine willingness to donate one's own organs and consent to the donation of those of a relative. This study confirms and develops further previous research findings that presumed consent organ donation policy positively affects the willingness of individuals to donate their own organs and those of relative by highlighting the importance of awareness of this regulation and an individual's level of social interactions in making choices about donation. Results found using interaction terms underline the importance of population awareness of organ donation legislation as well as the legislation type itself. Findings also point to the role of social interactions in influencing individuals' willingness to donate their organs or those of a relative.

Motives of corporate political donations: industry regulation, subjective judgement and the origins of pragmatic and ideological corporations.

PubMed

Harrigan, Nicholas M

2017-12-01

What motivates corporate political action? Are corporations motivated by their own narrow economic self-interest; are they committed to pursuing larger class interests; or are corporations instruments for status groups to pursue their own agendas? Sociologists have been divided over this question for much of the last century. This paper introduces a novel case - that of Australia - and an extensive dataset of over 1,500 corporations and 7,500 directors. The paper attempts to understand the motives of corporate political action by examining patterns of corporate political donations. Using statistical modelling, supported by qualitative evidence, the paper argues that, in the Australian case, corporate political action is largely motivated by the narrow economic self-interest of individual corporations. Firms' interests are, consistent with regulatory environment theory, defined by the nature of government regulation in their industry: those in highly regulated industries (such as banking) and those dependent on government support (such as defence) tend to adopt a strategy of hedging their political support, and make bipartisan donations (to both major parties). In contrast, firms facing hostile regulation (such as timber or mining), and those without strong dependence on state support (such as small companies) tend to adopt a strategy of conservative partisanship, and make conservative-only donations. This paper argues that regulatory environment theory needs to be modified to incorporate greater emphasis on the subjective political judgements of corporations facing hostile regulation: a corporation's adoption of conservative partisanship or hedging is not just a product of the objective regulation they face, but also whether corporate leaders judge such regulation as politically inevitable or something that can be resisted. Such a judgement is highly subjective, introducing a dynamic and unpredictable dimension to corporate political action. © London School of Economics and Political Science 2017.

Organ trafficking: global solutions for a global problem.

PubMed

Jafar, Tazeen H

2009-12-01

The organ trafficking market is on the rise worldwide. Numerous unfortunate stories of networks of brokers, physicians, and hospitals engaged in illegal trade have been featured in high-profile media. The profitable enterprises facilitating these unregulated services exploit the poor in underresourced countries and offer substandard medical care with unacceptable outcomes to the rich recipients. Despite efforts to boost altruistic organ donation and resolutions to curb transplant tourism, their implementation has been compromised. At the same time, the worldwide escalation in the number of patients with kidney failure coupled with a shortage in the supply of organs continues to fuel this trade. Thus, measures to enhance the donor pool in well-resourced countries to meet their own needs will act as a strong deterrent to the proliferation of transplant tourism in impoverished nations. Regulated schemes that include reimbursement for removing potential disincentives to organ donation and ensure the long-term safety of donors and their families are likely to increase living donations. Such socially responsible programs should be tested in both developed and developing countries for their own populations. It also is vital that developing countries establish a regulated, standardized, and ethical system of organ procurement; create awareness in physicians and the public; upgrade facilities and standardize medical care; and enforce legislation for transplantation. The World Health Organization, National Kidney Foundation, and international transplant and nephrology societies can have an instrumental role in facilitating initiatives in these critical areas. There should be clearly defined codes of conduct for health care facilities and professionals' roles in unregulated paid organ donations and transplants. Ultimately, physicians and transplant surgeons have the responsibility to ensure to the best of their ability that the organs they transplant were obtained upholding the highest standards of ethics.

A Website Intervention to Increase Knowledge About Living Kidney Donation and Transplantation Among Hispanic/Latino Dialysis Patients.

PubMed

Gordon, Elisa J; Feinglass, Joe; Carney, Paula; Vera, Karina; Olivero, Maria; Black, Anne; O'Connor, Kate Grubbs; Baumgart, Jessica MacLean; Caicedo, Juan Carlos

2016-03-01

Hispanic dialysis patients often encounter barriers to learning about living kidney donation and transplantation. Effective culturally targeted interventions to increase knowledge are lacking. We developed a culturally targeted educational website to enhance informed treatment decision making for end-stage kidney disease. A pretest/posttest intervention study was conducted among adult Hispanic patients undergoing dialysis at 5 dialysis centers in Chicago, Illinois. Surveys included a 31-item, multiple-choice pretest/posttest of knowledge about kidney transplantation and living donation, attitudes about the website, Internet use, and demographics. The intervention entailed viewing 3 of 6 website sections for a total of 30 minutes. The pretest/posttest was administered immediately before and after the intervention. Participants completed a second posttest via telephone 3 weeks thereafter to assess knowledge retention, attitudes, and use of the website. Sixty-three patients participated (96% participation rate). Website exposure was associated with a mean 17.1% same day knowledge score increase between pretest and posttest (P < .001). At 3 weeks, participants' knowledge scores remained 11.7% above pretest (P < .001). The greatest knowledge gain from pretest to 3-week follow-up occurred in the Treatment Options (P < .0001) and Cultural Beliefs and Myths (P < .0001) website sections. Most participants (95%) "agreed" or "strongly agreed" that they would recommend the website to other Hispanics. Web-based education for patients undergoing dialysis can effectively increase Hispanics' knowledge about transplantation and living kidney donation. Study limitations include small sample size and single geographic region study. Dialysis facilities could enable website access as a method of satisfying policy requirements to provide education about kidney transplantation. © 2016, NATCO.

Blood management and transfusion strategies in 600 patients undergoing total joint arthroplasty: an analysis of pre-operative autologous blood donation

PubMed Central

Perazzo, Paolo; Viganò, Marco; de Girolamo, Laura; Verde, Francesco; Vinci, Anna; Banfi, Giuseppe; Romagnoli, Sergio

2013-01-01

Background Blood loss during total joint arthroplasty strongly influences the time to recover after surgery and the quality of the recovery. Blood conservation strategies such as pre-operative autologous blood donation and post-operative cell salvage are intended to avoid allogeneic blood transfusions and their associated risks. Although widely investigated, the real effectiveness of these alternative transfusion practices remains controversial. Materials and methods The surgery reports of 600 patients undergoing total joint arthroplasty (312 hip and 288 knee replacements) were retrospectively reviewed to assess transfusion needs and related blood management at our institute. Evaluation parameters included post-operative blood loss, haemoglobin concentration measured at different time points, ASA score, and blood transfusion strategies. Results Autologous blood donation increased the odds of receiving a red blood cell transfusion. Reinfusion by a cell salvage system of post-operative shed blood was found to limit adverse effects in cases of severe post-operative blood loss. The peri-operative net decrease in haemoglobin concentration was higher in patients who had predeposited autologous blood than in those who had not. Discussion The strengths of this study are the high number of cases and the standardised procedures, all operations having been performed by a single orthopaedic surgeon and a single anaesthesiologist. Our data suggest that a pre-operative autologous donation programme may often be useless, if not harmful. Conversely, the use of a cell salvage system may be effective in reducing the impact of blood transfusion on a patient’s physiological status. Basal haemoglobin concentration emerged as a useful indicator of transfusion probability in total joint replacement procedures. PMID:23736922

Effects of the capping ligands, linkers and oxide surface on the electron injection mechanism of copper sulfide quantum dot-sensitized solar cells.

PubMed

Suárez, Javier Amaya; Plata, Jose J; Márquez, Antonio M; Sanz, Javier Fdez

2017-06-07

Quantum dot-sensitized solar cells, QDSCs, are a clean and effective alternative to fossil fuels to reduce CO 2 emissions. However, the different components that constitute the QDSCs and the difficulty of isolating experimentally their effects on the performance of the whole system slow down the development of more efficient devices. In this work, DFT calculations are combined with a bottom-up approach to differentiate the effect of each component on the electronic structure and absorption spectra. First, Cu 2 S QDs were built including a U parameter to effectively describe the localization of electrons. The effect of capping agents is addressed using ligands with different electron-donating/withdrawing groups. The role of linkers and their adsorption on the oxide surface are also examined. Finally, we propose a main indirect electron injection mechanism based on the position of the peaks of the spectra.

Organ and tissue donation in a regional paediatric intensive care unit: evaluation of practice.

PubMed

Carone, Laura; Alurkar, Shrirang; Kigozi, Phoebe; Vyas, Harish

2018-05-01

Approximately 2% of those on the organ transplant list in the UK are children. Early identification of donors and referral to organ donation teams (ODT) has proven to increase both the success rate of gaining consent and the number of organs actually retrieved. To evaluate the practice relating to organ donation for children receiving end-of-life care on a paediatric intensive care unit (PICU) measured against the National Guidelines. All children 0-18 who received their end-of-life care and died on the PICU. A retrospective cohort study of organ donation patterns including referral, approach, consent and donation. This involved a review of case notes on PICU between the years 2009 and 2014. One hundred five deaths were identified and 100 notes were examined and data analysed to ascertain if religion, age and length of stay on PICU impacted on practice. Eighty-six children met the early identification criteria for potential donors, 40 (46.5%) children were referred to the ODT and 33 (38.3%) families were approached regarding donation. Twenty-one (24.4%) families consented to donation. Seventeen donations took place with a total of 41 sets of organs/tissues retrieved. Despite the majority of children meeting early identification for potential donors, many were not being referred. All children on end-of-life care should be referred for potential organ donation. Organ donation needs to be seen as a priority for hospitals as a part of routine end-of-life care to help increase referral rates and give families the opportunity to donate. Many paediatric deaths are not referred for consideration of organ donation, despite guidelines stating that this process should be standard of care. Further optimization of referral rates may aid in increasing the number of organs available for donation. What is Known: • Shortage of organs continues to be a national problem. • NICE guidelines state that all patients who are on end-of-life care should have the option of organ donation explored. • Required referral both increases the number of donors and organs donated. What is New: • The process of identifying and referring children for paediatric organ donation. • Identifies that children are still not being referred for organ donation. • Organ donation is still not a priority for hospitals.

Determination of adiabatic ionization potentials and electron affinities of energetic molecules with the Gaussian-4 method

NASA Astrophysics Data System (ADS)

Manaa, M. Riad

2017-06-01

Adiabatic ionization potentials (IPad) and electron affinities (EAad) are determined with the Gaussian-4 (G4) method for the energetic molecules PETN, RDX, β-δ-HMX, CL-17, TNB, TNT, CL-14, DADNE, TNA, and TATB. The IPad and EAad values are in the range of 8.43-11.73 and 0.74-2.86 eV, respectively. Variations are due to substitutional effects of electron withdrawing and donating functional groups. Enthalpies of formation are also determined for several of these molecules to augment the list of recently reported G4 values. The calculated IPad and EAad provide quantitative assessment of such molecular properties as chemical hardness, molecular electronegativity, and "intrinsic" molecular physical hardness.

Quantum chemical calculations, molecular dynamic (MD) simulations and experimental studies of using some azo dyes as corrosion inhibitors for iron. Part 2: Bis-azo dye derivatives

NASA Astrophysics Data System (ADS)

Madkour, Loutfy H.; Kaya, Savaş; Guo, Lei; Kaya, Cemal

2018-07-01

The adsorption behavior and inhibition mechanism of five synthesized bis-azo dye (BAD) derivatives on the corrosion of iron in aerated HNO3 and NaOH were investigated by performing potentiostatic polarization, weight loss (WL), thermometric and UV-visible spectra measurements. DFT calculations is applied to study the correlation between corrosion inhibition and global reactivity descriptors such as: EHOMO, ELUMO, molecular gap (ΔE), the dipole moment (μ), the global hardness (η), softness(S), electronegativity (χ), proton affinity (PA), electrophilicity (ω), nucleophilicity (ɛ), electrons transferred from inhibitors to metal surface (ΔN), initial molecule-metal interaction energy (Δψ), total electronic energy (E) and the energy change during electronic back-donation process (ΔEb-d). To mimic the real environment of corrosion inhibition, molecular dynamic (MD) simulations in aqueous phase have also been modelled consisting of all concerned species (inhibitor molecule, H2O, H3O+ ion, NO3- ion, OH- and Fe surface). The results confirmed that BAD molecules inhibit iron by adsorption behavior through donating and accepting electrons together with the formation of [Fe (II) and Fe (III)-BAD] chelate complex compounds. BAD's behavior is mainly chemisorption with some physisorption obeyed Frumkin and that of El-Awady adsorption isotherm. Kinetic parameters such as: (Kb, 1/y, Kads, f, ΔG°ads) have been determined and discussed. Binding energies of BAD molecules on Fe (110) surface followed the order: BAD_ 2 > BAD_ 1 > BAD_ 3 > BAD_ 4 > BAD_ 5. Theoretical results were found to be consistent with the experimental data reported. Our results provide important atomic/molecular insights into the anticorrosive mechanism of inhibitor molecules, which could help in understanding the organic-metal interface and designing more appropriate organic corrosion inhibitors.

Oxoferryl-porphyrin radical catalytic intermediate in cytochrome bd oxidases protects cells from formation of reactive oxygen species.

PubMed

Paulus, Angela; Rossius, Sebastiaan Gijsbertus Hendrik; Dijk, Madelon; de Vries, Simon

2012-03-16

The quinol-linked cytochrome bd oxidases are terminal oxidases in respiration. These oxidases harbor a low spin heme b(558) that donates electrons to a binuclear heme b(595)/heme d center. The reaction with O(2) and subsequent catalytic steps of the Escherichia coli cytochrome bd-I oxidase were investigated by means of ultra-fast freeze-quench trapping followed by EPR and UV-visible spectroscopy. After the initial binding of O(2), the O-O bond is heterolytically cleaved to yield a kinetically competent heme d oxoferryl porphyrin π-cation radical intermediate (compound I) magnetically interacting with heme b(595). Compound I accumulates to 0.75-0.85 per enzyme in agreement with its much higher rate of formation (~20,000 s(-1)) compared with its rate of decay (~1,900 s(-1)). Compound I is next converted to a short lived heme d oxoferryl intermediate (compound II) in a phase kinetically matched to the oxidation of heme b(558) before completion of the reaction. The results indicate that cytochrome bd oxidases like the heme-copper oxidases break the O-O bond in a single four-electron transfer without a peroxide intermediate. However, in cytochrome bd oxidases, the fourth electron is donated by the porphyrin moiety rather than by a nearby amino acid. The production of reactive oxygen species by the cytochrome bd oxidase was below the detection level of 1 per 1000 turnovers. We propose that the two classes of terminal oxidases have mechanistically converged to enzymes in which the O-O bond is broken in a single four-electron transfer reaction to safeguard the cell from the formation of reactive oxygen species.

Oxoferryl-Porphyrin Radical Catalytic Intermediate in Cytochrome bd Oxidases Protects Cells from Formation of Reactive Oxygen Species*

PubMed Central

Paulus, Angela; Rossius, Sebastiaan Gijsbertus Hendrik; Dijk, Madelon; de Vries, Simon

2012-01-01

The quinol-linked cytochrome bd oxidases are terminal oxidases in respiration. These oxidases harbor a low spin heme b558 that donates electrons to a binuclear heme b595/heme d center. The reaction with O2 and subsequent catalytic steps of the Escherichia coli cytochrome bd-I oxidase were investigated by means of ultra-fast freeze-quench trapping followed by EPR and UV-visible spectroscopy. After the initial binding of O2, the O–O bond is heterolytically cleaved to yield a kinetically competent heme d oxoferryl porphyrin π-cation radical intermediate (compound I) magnetically interacting with heme b595. Compound I accumulates to 0.75–0.85 per enzyme in agreement with its much higher rate of formation (∼20,000 s−1) compared with its rate of decay (∼1,900 s−1). Compound I is next converted to a short lived heme d oxoferryl intermediate (compound II) in a phase kinetically matched to the oxidation of heme b558 before completion of the reaction. The results indicate that cytochrome bd oxidases like the heme-copper oxidases break the O–O bond in a single four-electron transfer without a peroxide intermediate. However, in cytochrome bd oxidases, the fourth electron is donated by the porphyrin moiety rather than by a nearby amino acid. The production of reactive oxygen species by the cytochrome bd oxidase was below the detection level of 1 per 1000 turnovers. We propose that the two classes of terminal oxidases have mechanistically converged to enzymes in which the O–O bond is broken in a single four-electron transfer reaction to safeguard the cell from the formation of reactive oxygen species. PMID:22287551

Knowledge of Kidney Donation Among Care Givers in Two Tertiary Hospitals in Southwest Nigeria.

PubMed

Adejumo, Oluseyi A; Solarin, Adaobi U; Abiodun, Moses T; Akinbodewa, Ayodeji A

2017-05-01

One of the major challenges of kidney transplantation is shortage of kidney donors. Care givers (CGs) are potential kidney donors, but the majority of them are unwilling to donate due to inadequate knowledge on kidney donation. This study evaluated the knowledge of kidney donation and its determinants among CGs in two tertiary hospitals in Southwest Nigeria. This was a cross-sectional study that was carried out in the Kidney Care Centre (KCC), Ondo and Babcock University Teaching Hospital (BUTH), Ilishan-Remo using a self-administered pretested questionnaire that assessed knowledge of kidney donation and its determinants. Pvalue of <0.05 was taken as significant. A total of 244 respondents participated in the study. The majority were below 40 years, married, and female. The proportion of respondents with adequate knowledge of kidney donation was 63.4%. More respondents from BUTH compared to KCC had adequate knowledge of kidney donation (80% vs. 46.7%, P ≤ 0.001). Similarly, the mean knowledge score was higher in respondents from BUTH (P ≤ 0.001). Factors that determined knowledge of kidney donation were female gender (AOR: 3.43, 95% CI: 1.25-9.40, P = 0.02) and social class (AOR: 1.22, 95% CI: 0.50-2.95, P ≤ 0.001). There was positive correlation between knowledge of kidney donation among the respondents from both hospitals and their willingness to donate kidneys (r = 0.439, P ≤ 0.001). Knowledge of kidney donation was better among BUTH's respondents. Gender and social class were predictors of knowledge of kidney donation. Improving knowledge of kidney donation may improve willingness to donate among the public. © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.