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Publication
Journal: Nursing Economics
March/4/2008
Abstract
OBJECTIVE
Identify the extent to which hospital boards of trustees, CEOs, and CNOs are engaged in quality and safety at the leadership and governance level and how CNOs can support board engagement in quality and safety.
BACKGROUND
Although research is emerging, still relatively little is known about the impact and interface of hospital boards of trustees, CEOs, and nursing executives related to improving quality and patient safety.
METHODS
73 telephone interviews were conducted with hospital board chairs, CEOs, and CNOs from a convenience sample of 63 U.S. hospitals. The interviews (22 of which were with CNOs) lasted 30 to 45 minutes and were supplemented by a focus group of five nursing executives.
RESULTS
There are significant differences in the perceptions of CNOs versus those of board chairs and CEOs. CNOs reported a greater familiarity of landmark reports on quality and patient safety than board chairs. CEOs and board chairs gave substantially higher ratings to integration of quality planning. Boards have limited comprehension of salient nursing quality issues.
CONCLUSIONS
CNOs have a critical role as boardroom champions of patient safety and quality improvement.
Publication
(16626424; CEO; 10.1111/j.1442-9071.2006.01138.x)
Journal: Clinical and Experimental Ophthalmology
June/11/2006
Abstract
BACKGROUND
The foveal avascular zone (FAZ) is known to enlarge in diabetic retinopathy. In a preliminary study, the authors applied a region growing algorithm to fluorescein angiograms to detect the FAZ in a semi-automated fashion.
METHODS
The FAZ in 44 fluorescein angiograms of 44 eyes of 41 patients with diabetic retinopathy underwent manual outlining, then analysis with the region growing function of the ENVI image analysis software. The same algorithm was applied after median filtering of the images.
RESULTS
Correlation coefficient was 0.98 between the first two authors, 0.89 between the first author and semi-automated detection before median filtering and 0.91 after median filtering. Average surface areas however, were smaller with semi-automated detection (1951 pixels before and 2226 pixels after median filtering) than with manual detection (3032 pixels).
CONCLUSIONS
Semi-automated detection of the FAZ is possible, but refinements need to be made in angiogram quality and/or image pretreatment to improve results.
Publication
Journal: Dalton Transactions
October/2/2011
Abstract
CeO(2) nanoparticles/graphene nanocomposite is fabricated by depositing CeO(2) nanoparticles onto three-dimensional graphene material and its supercapacitor performance is further investigated. The nanocomposite shows a high specific capacitance and power density, demonstrating a strong synergistic effect possibly contributed from improved conductivity of CeO(2) and better utilization of graphene.
Publication
Journal: Chemical Communications
September/21/2010
Abstract
In contrast to gamma-Al(2)O(3), TiO(2), ZrO(2), MgO and Y(2)O(3), CeO(2) is a reusable catalyst for the reaction of CO(2) with omega-aminoalcohols to form cyclic carbamates; the highest yield (68%) was obtained for the preparation of N-alkyl 1,3-oxazolidin-2-ones from N-alkyl ethanolamines.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
May/6/2009
Abstract
Mixed-metal oxides play a very important role in many areas of chemistry, physics, materials science, and geochemistry. Recently, there has been a strong interest in understanding phenomena associated with the deposition of oxide nanoparticles on the surface of a second (host) oxide. Here, scanning tunneling microscopy, photoemission, and density-functional calculations are used to study the behavior of ceria nanoparticles deposited on a TiO(2)(110) surface. The titania substrate imposes nontypical coordination modes on the ceria nanoparticles. In the CeO(x)/TiO(2)(110) systems, the Ce cations adopt an structural geometry and an oxidation state (+3) that are quite different from those seen in bulk ceria or for ceria nanoparticles deposited on metal substrates. The increase in the stability of the Ce(3+) oxidation state leads to an enhancement in the chemical and catalytic activity of the ceria nanoparticles. The codeposition of ceria and gold nanoparticles on a TiO(2)(110) substrate generates catalysts with an extremely high activity for the production of hydrogen through the water-gas shift reaction (H(2)O + CO ->> H(2) + CO(2)) or for the oxidation of carbon monoxide (2CO + O(2) ->> 2CO(2)). The enhanced stability of the Ce(3+) state is an example of structural promotion in catalysis described here on the atomic level. The exploration of mixed-metal oxides at the nanometer level may open avenues for optimizing catalysts through stabilization of unconventional surface structures with special chemical activity.
Publication
Journal: Chemical Communications
June/19/2012
Abstract
Gold nanoparticles supported on CeO(2) were found to be efficient photocatalysts for three selective reductions of organic compounds at ambient temperatures, under irradiation of visible light; their reduction ability can be tuned by manipulating the irradiation wavelength.
Publication
Journal: Journal of Chemical Physics
June/8/2010
Abstract
Oxygen vacancy formation and migration in ceria (CeO(2)) is central to its performance as an ionic conductor. It has been observed that ceria doped with suitable aliovalent cationic dopants improves its ionic conductivity. To investigate this phenomenon, we present total energy calculations within the framework of density functional theory to study oxygen vacancy migration in ceria and Pr-doped ceria (PDC). We report activation energies for oxygen vacancy formation and migration in undoped ceria and for different migration pathways in PDC. The activation energy value for oxygen vacancy migration in undoped ceria was found to be in reasonable agreement with the available experimental and theoretical results. Conductivity values for reduced undoped ceria calculated using theoretical activation energy and attempt frequency were found in reasonably good agreement with the experimental data. For PDC, oxygen vacancy formation and migration were investigated at first, second, and third nearest neighbor positions to a Pr ion. The second nearest neighbor site is found to be the most favorable vacancy formation site. Vacancy migration between first, second, and third nearest neighbors was calculated (nine possible jumps), with activation energies ranging from 0.41 to 0.78 eV for first-nearest-neighbor jumps. Overall, the presence of Pr significantly affects vacancy formation and migration, in a complex manner requiring the investigation of many different migration events. We propose a relationship illuminating the role of additional dopants toward lowering the activation energy for vacancy migration in PDC.
Publication
Journal: Cancer Chemotherapy and Pharmacology
April/8/2008
Abstract
Here we report an unusual case of mixed Wilms' tumour and angiosarcoma in a 38-year-old female patient who presented with haematuria and right lower back pain. A computed tomographic (CT) scan confirmed a massive renal tumour associated with extensive retroperitoneal lymph node involvement, bony metastases and a right hip fracture. She was initially managed with palliative nephrectomy, which was followed by rapid postoperative deterioration. Histopathology revealed differentiated adult Wilms' tumour with renal angiosarcoma, whereas the pathology of the para-aortic lymph node and bone metastasis revealed angiosarcoma only. In view of her cachexia and cytopaenia, emergency chemotherapy was initiated using a modified regimen of carboplatin, etoposide and vincristine (CEO) in preference to the more traditional but less well-tolerated VAC (vincristine, actinomycin D, cyclophosphamide). Four cycles of this protocol yielded a dramatic response on re-staging CT scan. This case suggests that highly angiogenic tumours such as angiosarcoma may be effectively palliated using agents usually reserved for refractory Wilms' tumour, and supports the view that adult Wilms' tumour is more sensitive to such agents.
Publication
Journal: Journal of the American Chemical Society
February/28/2010
Abstract
At small coverages of ceria on TiO(2)(110), the CeO(x) nanoparticles have an unusual coordination mode. Scanning tunneling microscopy and density-functional calculations point to the presence of Ce(2)O(3) dimers, which form diagonal arrays that have specific orientations of 0, 24, and 42 degrees with respect to the [1 -1 0] direction of the titania substrate. At high coverages of ceria on TiO(2)(110), the surface exhibits two types of terraces. In one type, the morphology is not very different from that observed at low ceria coverage. However, in the second type of terrace, there is a compact array of ceria particles with structures that do not match the structures of CeO(2)(111) or CeO(2)(110). The titania substrate imposes on the ceria nanoparticles nontypical coordination modes, enhancing their chemical reactivity. This phenomenon leads to a larger dispersion of supported metal nanoparticles (M = Au, Cu, Pt) and makes possible the direct participation of the oxide in catalytic reactions. The M/CeO(x)/TiO(2)(110) surfaces display an extremely high catalytic activity for the water-gas shift reaction that follows the sequence Au/CeO(x)/TiO(2)(110) < Cu/CeO(x)/TiO(2)(110) < Pt/CeO(x)/TiO(2)(110). For low coverages of Cu and CeO(x), Cu/CeO(x)/TiO(2)(110) is 8-12 times more active than Cu(111) or Cu/ZnO industrial catalysts. In the M/CeO(x)/TiO(2)(110) systems, there is a strong coupling of the chemical properties of the admetal and the mixed-metal oxide: The adsorption and dissociation of water probably take place on the oxide, CO adsorbs on the admetal nanoparticles, and all subsequent reaction steps occur at the oxide-admetal interface. The high catalytic activity of the M/CeO(x)/TiO(2)(110) surfaces reflects the unique properties of the mixed-metal oxide at the nanometer level.
Publication
Journal: Chemistry - A European Journal
June/4/2009
Abstract
A gamma-alumina-supported silver cluster catalyst--Ag/Al(2)O(3)--has been shown to act as an efficient heterogeneous catalyst for oxidant-free alcohol dehydrogenation to carbonyl compounds at 373 K. The catalyst shows higher activity than conventional heterogeneous catalysts based on platinum group metals (PGMs) and can be recycled. A systematic study on the influence of the particle size and oxidation state of silver species, combined with characterization by Ag K-edge XAFS (X-ray absorption fine structure) has established that silver clusters of sizes below 1 nm are responsible for the higher specific rate. The reaction mechanism has been investigated by kinetic studies (Hammett correlation, kinetic isotope effect) and by in situ FTIR (kinetic isotope effect for hydride elimination reaction from surface alkoxide species), and the following mechanism is proposed: 1) reaction between the alcohol and a basic OH group on the alumina to yield alkoxide on alumina and an adsorbed water molecule, 2) C-H activation of the alkoxide species by the silver cluster to form a silver hydride species and a carbonyl compound, and 3) H(2) desorption promoted by an acid site in the alumina. The proposed mechanism provides fundamental reasons for the higher activities of silver clusters on acid-base bifunctional support (Al(2)O(3)) than on basic (MgO and CeO(2)) and acidic to neutral (SiO(2)) ones. This example demonstrates that catalysts analogous to those based on of platinum group metals can be designed with use of a less expensive d(10) element--silver--through optimization of metal particle size and the acid-base natures of inorganic supports.
Publication
Journal: Chemistry - A European Journal
February/8/2009
Abstract
A great variety of metal oxide nanoparticles have been readily synthesized by using alkali metal oxides, M(2)O (M is Na or Li) and soluble metal salts (metal chlorides) in polar organic solutions, for example, methanol and ethanol, at room temperature. The oxidation states of the metals in the resulting metal oxides (Cu(2)O, CuO, ZnO, Al(2)O(3), Fe(2)O(3), Bi(2)O(3), TiO(2), SnO(2), CeO(2), Nb(2)O(5), WO(3), and CoFe(2)O(4)) range from 1 to 6 and remain invariable through the reactions where good control of stoichiometry is achieved. Metal oxide nanoparticles are 1-30 nm and have good monodispersivity and displayed comparable optical spectra. These syntheses are based on a general ion reaction pathway during which the precipitate occurs when O(2-) ions meet metal cations (M(n+)) in anhydrous solution and the reaction equation is M(n+) + n/2 O(2-) ->> MO(n/2) (n=1-6).
Publication
Journal: Biomaterials
June/23/2003
Abstract
ZrO(2) (4% CeO(2)) and ZrO(2) (3% Y(2)O(3)) coatings were deposited on titanium (Ti) and CoCrMo implants using plasma spraying and the adhesive, morphological and structural properties of the plasma-sprayed coatings were evaluated. Characterization of these coatings was performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), surface roughness, hardness, and adhesive strength. XRD patterns showed that both the coatings appeared to be primitive tetragonal phase. SEM observations showed that both the ZrO(2) coatings appeared to be rough, porous and melted. The cross-section surface morphology of the coatings, coating-substrate interfaces and substrates without acid etching was very dense and smooth. After acid etching, as compared to the dense ZrO(2) coating-CoCrMo substrate interfaces, the thin gaps appeared within the ZrO(2) coating-Ti substrate interfaces. It is suggested that plasma spraying probably formed an amorphous Ti layer in the coating-Ti substrate interface that can be removed by acid etching. The average surface roughness of ZrO(2) (3% Y(2)O(3)) and ZrO(2) (4% CeO(2)) coatings was correlated to the starting powder size and substrates. No significant difference between the hardness of all coatings and substrates was observed. The adhesive strengths of ZrO(2) (4% CeO(2)) coating to Ti and CoCrMo substrates were higher than 68MPa and significantly greater than that of ZrO(2) (3% Y(2)O(3)) coatings.
Publication
(16451270; CEO; 10.1111/j.1442-9071.2006.01127.x)
Journal: Clinical and Experimental Ophthalmology
May/7/2006
Abstract
The clinical presentation and electrophysiological findings are described of three consecutive cases with pericentral pigmentary retinal degeneration. The responses to bright flashes after dark adaptation showed negative waveform shape in all cases. Rod responses were strongly reduced compared with cone responses. Cone electroretinograms elicited by long-duration stimuli showed greater loss of the on-response than the off-response. The ratio of the on-response amplitude to off-response amplitude of these patients (0.52 +/- 0.12; mean +/- SD, n = 6) was significantly smaller than that of normal subject (0.83 +/- 0.21; mean +/- SD, n = 8) (Mann-Whitney U-test, P < 0.01). The electrophysiological findings of these cases suggest a greater defect of inner retinal function, especially in transmission between photoreceptors and depolarizing bipolar cells.
Publication
Journal: Meat Science
July/28/2014
Abstract
The utility of packaging films consisting of cast polypropylene/polyvinyl alcohol with rhubarb ethanolic extracts (REE) and cinnamon essential oil (CEO) in maintaining fresh beef quality was investigated. Fresh beefsteaks were packed with antimicrobial films containing different concentrations of REE and CEO. Beef characteristics, including pH, total viable counts, instrumentally measured color, weight loss, total volatile base nitrogen (TVB-N) and sensory quality were determined. All experimental films significantly inhibited bacterial growth (p<0.05) and maintained the pH and TVB-N of beefsteaks. Three of four experimental films significantly reduced instrumental color loss (p<0.05). Antimicrobial packaging films efficiently maintained the quality of fresh beefsteaks during storage.
Publication
Journal: Nutrients
October/17/2018
Abstract
Chinotto (Citrus myrtifolia Raf.) is a widely diffused plant native from China and its fruits have a wide-spread use in confectionary and drinks. Remarkably, only little has been reported thus far on its bioactive properties, in contrast to those of the taxonomically related bergamot (Citrus bergamia Risso). The present study aimed to investigate potential in vitro anti-inflammatory and radical scavenging properties of chinotto essential oils (CEOs) and to establish to what extent their composition and bioactivities are dependent on maturation. Essential oil from half ripe chinotto (CEO2) reduced the production of nitric oxide (NO) and the expression of inflammatory genes, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), cytokines, including interleukin-1β (IL-1β) and interleukin-6 (IL-6), and chemokine monocyte chemotactic protein-1 (MCP-1) by lipopolysaccharide (LPS)-stimulated RAW264,7 macrophages. Limonene, linalool, linalyl acetate, and γ-terpinene were found to be the main components in CEO2. Moreover, CEO2 showed high radical scavenging activity measured as Trolox equivalents (TE) against both 2,2′-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS). These findings show that chinotto essential oil represents a valuable part of this fruit and warrants further in vivo studies to validate its anti-inflammatory potential.
Publication
Journal: Drugs in R and D
February/2/2005
Abstract
INEX Pharmaceuticals is developing a liposomal formulation of vincristine [Onco TCS, vincacine, VSLI, Vincristine sulfate liposomes for injection] for the treatment of relapsed aggressive non-Hodgkin's lymphoma (NHL) and other cancers. It is being developed using INEX's proprietary drug-delivery technology platform called the transmembrane carrier systems (TCS), which enables the targeted intracellular delivery of various therapeutic agents. Liposomal vincristine is expected to have certain advantages over the existing standard preparation of vincristine because the use of TCS technology enables the vincristine to circulate in the blood for longer, accumulate in the tumour, and be released over an extended period of time at the tumour site. The application of TCS technology to any agent, including vincristine, has the potential to increase the efficacy and decrease the side effects of the agent. INEX decided in 1998 to focus on gaining approval for liposomal vincristine in the treatment of relapsed aggressive NHL because no standard therapy was approved for this indication. In 1999, liposomal vincristine was granted accelerated development status by the US FDA, which enables the FDA to approve it based on the surrogate endpoint of a single clinical trial. In addition, the FDA granted liposomal vincristine fast track status in August 2000. In April 2001, INEX and Elan Corporation formed a joint venture for the development and commercialisation of liposomal vincristine, with both companies contributing assets to the venture including worldwide rights to the product and intellectual property rights. The joint venture was called IE Oncology. However, in June 2002, Elan announced that it was going to focus its business strategy on three specific areas, which would not include cancer therapies. INEX announced it had regained 100% ownership of liposomal vincristine in April 2003, by reacquiring the 19.9% equity interest held by Elan and in addition retaining a fully paid-up licence to Elan's intellectual property pertaining to liposomal vincristine. All obligations to Elan under the agreement will be met through three milestone payments totalling $8 million. Some of the milestones may be paid in shares valued at the then current market price. In January 2004, INEX and Enzon Pharmaceuticals formed a strategic partnership to develop and commercialise liposomal vincristine. Under the terms of the agreement, Enzon receives the exclusive North American commercialisation rights for liposomal vincristine for all indications. INEX will receive upfront and milestone payments as well as a percentage of commercial sales. Additionally, the formation of this partnership triggered a US$3 million payment from INEX to the former joint venture partner, Elan Corporation. Nine clinical trials of liposomal vincristine are currently being conducted, including one phase I/II trial and eight phase II trials. A phase II/III trial was completed in December 2002. In September 2003, Inex commenced a 'rolling submission' for liposomal vincristine by submitting the first of three major sections of the NDA to the FDA. The second major section was submitted to the FDA in December 2003. INEX expects to complete the filing with the submission of the clinical section of the NDA in the first quarter of 2004. Dow Jones Newswires reported on 1 October 2001 that the CEO of INEX expects Onco TCS to achieve sales of between $US100 and $US400 million annually for the company. FDA approval was then predicted for late 2002 or early 2003.
Publication
(16626442; CEO; 10.1111/j.1442-9071.2006.01150.x)
Journal: Clinical and Experimental Ophthalmology
June/11/2006
Abstract
This interventional case report describes a patient with a combined hamartoma of the retina and retinal pigment epithelium (RPE), which was treated with photodynamic therapy (PDT) with Verteporfin. A 17-year-old girl presented with a combined hamartoma of the retina and RPE. Progressive decrease in vision due to vascular leakage and macular involvement led to the decision to treat this lesion with PDT. Rapid vascular closure occurred after PDT as confirmed by fundus fluorescein angiography and the clinical appearance gradually improved. However, visual acuity did not improve substantially. PDT with Verteporfin could be considered as a treatment modality for combined hamartomas of the retina and RPE, which demonstrate progressive vascular leakage.
Publication
Journal: Chemical Research in Toxicology
September/20/1998
Abstract
A fast, highly specific analytical method was developed to quantify 1,N6-ethenoadenine (epsilonA) in urine of rats. epsilonA is a highly mutagenic DNA adduct generated by vinyl chloride (VC) exposures as well as endogenously from lipid peroxidation. epsilonA was concentrated through extraction from rat urine by immunoaffinity chromatography and quantitated by liquid chromatography/electrospray ionization mass spectrometry (LC/ESI-MS). The average epsilonA recovery by immunoaffinity extraction was 66%. The LC/ESI-MS selected-ion monitoring (SIM) of the response ratio of epsilonA to its isotopically labeled internal standard [15N5]epsilonA was linear (r2 = 0.999) and reproducible from 0.15 to 30 pmol/injection. The detection limit obtained in the routine analysis of urine of unexposed rats was 270 fmol/sample with a signal-to-noise ratio (S/N) 3:1. The concentration of endogenous epsilonA was determined to be 21.6 +/- 14.8 pmol/mL (3 rats). Following portal injection of chloroethylene oxide (CEO; the putative active metabolite of VC), the rate of epsilonA excretion in urine was greatest from 0 to 24 h, with approximately 90% of the CEO-induced epsilonA excreted. By 132 h, the excretion of epsilonA was similar to pretreatment amounts. The accuracy of the quantitation was 107 +/- 6% (n = 4), established by analyzing urine of an unexposed rat spiked with authentic epsilonA. These data indicate that the LC/ESI-MS with immunoaffinity extraction method is precise and accurate for epsilonA quantification. The measurement of epsilonA in urine provides a potential biomarker for exposure to chemicals and processes that form this adduct.
Publication
Journal: Journal of Healthcare Management
May/12/2004
Abstract
Debates often arise about who is best suited to manage a healthcare organization. Therefore, we argue that an examination of the ability of healthcare organizations' chief executive officers (CEOs) to make strategic decisions is warranted. Is the most appropriate leader the medically educated CEO, whose training in patient care allows him or her to be most cognizant of the quality-of-care needs of the organization? Or is it the managerially educated CEO, whose training makes him or her most aware of the organization's financial needs? This article presents a study involving senior managers from two integrated healthcare organizations. The study revealed that no significant differences exist between medically educated and managerially educated senior managers in their ability to make strategic decisions that maximize the net income or the quality of care of the healthcare organization. The debate that pits the "MDs" against the "MBAs" is misdirected. Characteristics other than educational degree appear to have a stronger influence on a CEO's ability to make successful strategic decisions. Therefore, candidates' educational background should not play such an important role in the processes for selecting CEOs.
Publication
Journal: Medical Care Research and Review
December/21/2000
Abstract
This article examines the degree to which managed care organizations (MCOs) are reorganizing to take responsibility for the quality of care and service they provide. Specifically, factors prompting plans to focus on quality improvement (QI) and how they may be building the capacity to improve quality are considered. The authors' analysis is based on executive interviews with the plan medical directors, QI directors, and chief executive officers (CEOs) in a sample of 24 health plans. The overall response rate was 58.3 percent (medical director = 62.5 percent, QI director = 79.2 percent, CEO = 33.3 percent). The authors queried respondents about (1) perceived drivers and obstacles to the development of an effective QI program, (2) plan organizational structure for QI, and (3) technical capacities for data collection, management, and performance measurement. The results suggest that MCOs are responding to outside pressures to engage in QI. They are reorganizing their management structures and more slowly and tentatively are building technical capacity for QI.
Publication
Journal: Harvard Business Review
July/21/2004
Abstract
An effective executive does not need to be a leader in the typical sense of the word. Peter Drucker, the author of more than two dozen HBR articles, says some of the best business and nonprofit CEOs he has worked with over his 65-year consulting career were not stereotypical leaders. They ranged from extroverted to nearly reclusive, from easygoing to controlling, from generous to parsimonious. What made them all effective is that they followed the same eight practices: They asked, "What needs to be done?" They also asked, "What is right for the enterprise?" They developed action plans. They took responsibility for decisions. They took responsibility for communicating. They were focused on opportunities rather than problems. They ran productive meetings. And they thought and said "we" rather than "I." The first two practices provided them with the knowledge they needed. The next four helped them convert this knowledge into effective action, for knowledge is useless to executives until it has been translated into deeds. The last two ensured that the whole organization felt responsible and accountable. Effective executives know that they have authority only because they have the trust of the organization. This means they must think of the needs and opportunities of the organization before they think of their own needs and opportunities. The author also suggests a ninth practice that's so important, he elevates it to the level of a rule: Listen first, speak last. The demand for effective executives is much too great to be satisfied by those few people who are simply born to lead. Effectiveness is a discipline. And, like every discipline, it can be learned and must be earned.
Publication
Journal: Theriogenology
October/6/2005
Abstract
This study examined the effect of atrial natriuretic peptide (ANP) on porcine cumulus-enclosed oocyte (CEO) maturation and cumulus expansion. ANP negatively regulated follicle-stimulating hormone (FSH)-stimulated germinal vesicle breakdown (GVBD; 90.1, 81.2 and 68.2% for FSH, FSH+10nM ANP and FSH+1 microM ANP, respectively), first polar body emission (PB1; 86.1, 75.3 and 53.3% for FSH, FSH+1 nM ANP and FSH+1 microM ANP, respectively) and cumulus expansion (CEI; 3.47, 3.16 and 2.43 for FSH, FSH+1 nM ANP and FSH+1 microM ANP, respectively) in a dose-dependent manner when CEOs were cultured in the maturation medium containing porcine follicular fluid (pFF). This negative effect showed a time-dependent manner after preincubation with 100 nM ANP for 5h (78.4% PB1), 10h (81.7% GVBD and 74.1% PB1), 20 h (78.5% GVBD and 68.9% PB1), and 44 h (75.3% GVBD and 60.5% PB1), respectively. ANP also significantly inhibited FSH-induced porcine oocyte GVBD (47.6% versus 83.8%) and PB1 emission (22.4% versus 45.2%) when CEOs were cultured in pFF-free maturation medium. cGMP analog 8-Br-cGMP (10 microM to 1mM) mimicked the effects of ANP on GVBD, PB1, and CEI. The negative effect of ANP was completely reversed by KT5823 (a specific inhibitor of cGMP-dependent protein kinase), while C-ANP-(4-23) (an analogue of ANP and specific binder for natriuretic peptide receptors-C) was ineffective in oocyte maturation. Neither ANP nor C-ANP-(4-23) had an effect on spontaneous porcine oocyte maturation and cumulus expansion. These results suggested that ANP negatively regulates FSH-activated porcine oocyte meiotic resumption, meiotic maturation and cumulus expansion. The function of ANP on porcine oocyte maturation is via the cGMP dependent protein kinase (PKG) pathway.
Publication
Journal: PLoS ONE
September/18/2012
Abstract
Significant advances have been made on our understanding of the fate and transport of engineered nanomaterials. One unexplored aspect of nanoparticle aggregation is how environmental stimuli such as light exposure and temperature variations affect the mobility of engineered nanoparticles. In this study, TiO(2), ZnO, and CeO(2) were chosen as model materials for investigating the mobility of nanoparticles under three external stimuli: heat, light and sonication. Sunlight and high power sonication were able to partially disagglomerate metal oxide clusters, but primary particles bonded by solid state necks were left intact. A cycle of temperature increase from 25°C to 65°C and then decrease back was found to disagglomerate the compact clusters in the heating phase and reagglomerate them as more open fractal structures during the cooling phase. A fractal model summing the pair-wise DLVO interactions between primary particles within two fractal agglomerates predicts weak attractions on the order of a few kT. Our study shows that common environmental stimuli such as light exposure or temperature variation can disagglomerate nanoparticle clusters and enhance their mobility in open waters. This phenomenon warrants attention since it is likely that metal oxide nanoparticles will experience these natural stimuli during their transport in the environment.
Publication
Journal: NeuroImage
January/18/2011
Abstract
The human amygdala responds to first impressions of people as judged from their faces, such as normative judgments about the trustworthiness of strangers. It is unknown, however, whether amygdala responses to first impressions can be validated by objective criteria. Here, we examined amygdala responses to faces of Chief Executive Officers (CEOs) where real-world outcomes could be measured objectively by the amounts of profits made by each CEO's company. During fMRI scanning, participants made incidental judgments about the symmetry of each CEO's face. After scanning, participants rated each CEO's face on leadership ability. Parametric analyses showed that greater left amygdala response to the CEOs' faces was associated with higher post-scan ratings of the CEOs' leadership ability. In addition, greater left amygdala response was also associated with greater profits made by the CEOs' companies and this relationship was statistically mediated by external raters' perceptions of arousal. Thus, amygdala response reflected both subjective judgments and objective measures of leadership ability based on first impressions.
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