Long-term cloud condensation nuclei number concentration, particle number size distribution and chemical composition measurements at regionally representative observatories

Schmale, Julia,Henning, Silvia,Decesari, Stefano,Henzing, Bas,Keskinen, Helmi,Sellegri, Karine,Ovadnevaite, Jurgita,Pö,hlker, Mira L.,Brito, Joel,Bougiatioti, Aikaterini,Kristensson, Adam,Kaliviti Copernicus GmbH 2018 Atmospheric Chemistry and Physics Vol.18 No.4

<P><p><strong>Abstract.</strong> Aerosol-cloud interactions (ACI) constitute the single largest uncertainty in anthropogenic radiative forcing. To reduce the uncertainties and gain more confidence in the simulation of ACI, models need to be evaluated against observations, in particular against measurements of cloud condensation nuclei (CCN). Here we present a data set - ready to be used for model validation - of long-term observations of CCN number concentrations, particle number size distributions and chemical composition from 12 sites on 3 continents. Studied environments include coastal background, rural background, alpine sites, remote forests and an urban surrounding. Expectedly, CCN characteristics are highly variable across site categories. However, they also vary within them, most strongly in the coastal background group, where CCN number concentrations can vary by up to a factor of 30 within one season. In terms of particle activation behaviour, most continental stations exhibit very similar activation ratios (relative to particles<span class='thinspace'></span><span class='inline-formula'>&gt;</span><span class='thinspace'></span>20<span class='thinspace'></span>nm) across the range of 0.1 to 1.0<span class='thinspace'></span>% supersaturation. At the coastal sites the transition from particles being CCN inactive to becoming CCN active occurs over a wider range of the supersaturation spectrum.</p> <p>Several stations show strong seasonal cycles of CCN number concentrations and particle number size distributions, e.g. at Barrow (Arctic haze in spring), at the alpine stations (stronger influence of polluted boundary layer air masses in summer), the rain forest (wet and dry season) or Finokalia (wildfire influence in autumn). The rural background and urban sites exhibit relatively little variability throughout the year, while short-term variability can be high especially at the urban site.</p> <p>The average hygroscopicity parameter, <span class='inline-formula'><i>κ</i></span>, calculated from the chemical composition of submicron particles was highest at the coastal site of Mace Head (0.6) and lowest at the rain forest station ATTO (0.2-0.3). We performed closure studies based on <span class='inline-formula'><i>κ</i></span>-Köhler theory to predict CCN number concentrations. The ratio of predicted to measured CCN concentrations is between 0.87 and 1.4 for five different types of <span class='inline-formula'><i>κ</i></span>. The temporal variability is also well captured, with Pearson correlation coefficients exceeding 0.87.</p> <p>Information on CCN number concentrations at many locations is important to better characterise ACI and their radiative forcing. But long-term comprehensive aerosol particle characterisations are labour intensive and costly. Hence, we recommend operating “migrating-CCNCs” to conduct collocated CCN number concentration and particle number size distribution measurements at individual locations throughout one year at least to derive a seasonally resolved hygroscopicity parameter. This way, CCN number concentrations can only be calculated based on continued particle number size distribution information and greater spatial coverage of long-term measurements can be achieved.</p> </P>

MORPHOLOGY AND OXIDATION KINETICS OF CI ENGINE’S BIODIESEL PARTICULATE MATTERS ON CORDIERITE DIESEL PARTICULATE FILTERS USING TGA

P. KARIN,J. BOONSAKDA,K. SIRICHOLATHUM,E. SAENKHUMVONG,C. CHAROENPHONPHANICH,K. HANAMURA 한국자동차공학회 2017 International journal of automotive technology Vol.18 No.1

The impact of small compression ignition (CI) engine operation conditions and fuel properties on diesel and biodiesel particulate matters (PMs) quantity using opacity smoke meter is investigated. The biodiesel engine’s PMs are around a half of diesel engine PMs under the same engine operation conditions. Morphology of both engine’s PMs are also studied using a Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and image processing method. The average primary nanoparticle sizes of diesel and biodiesel engine’s PMs are approximately 34 nm and 32 nm, respectively. The result shows that engine operation condition and fuel property are strongly impact on the quantity and size distribution of primary nanoparticles emission. PM oxidation kinetics on conventional cordierite Diesel Particulate Filters (DPFs) powders by Thermo-gravimetric analysis (TGA) is also successfully studied. The calculated apparent activation energies of biodiesel engine’s PM oxidation on conventional cordierite DPFs powders are lower than that of diesel engine’s PM and carbon black because of unburned oxygenated molecule. The calculated apparent activation energy of biodiesel engine’s PM and diesel engine’s PM oxidize on conventional cordierite DPFs powders with pure air are in the range of 109 ~ 131 kJ/mole and 117 ~ 130 kJ/mole, respectively. It might be expected that smaller primary nanoparticle size of biodiesel engine’s PMs and biooxygenate unburned hydrocarbon can promote more PM oxidation rate during vehicle’s DPF regeneration process.

OXIDATION KINETICS OF SMALL CI ENGINE'S BIODIESEL PARTICULATE MATTER

P. KARIN,M. BORHANIPOUR,Y. SONGSAENGCHAN,S. LAOSUWAN,C. CHAROENPHONPHANICH,N. CHOLLACOOP,K. HANAMURA 한국자동차공학회 2015 International journal of automotive technology Vol.16 No.2

Particulate matters (PMs) oxidation kinetics by Thermo-gravimetric analysis (TGA) was successfully studied. The chemical content percentage of PM can be divided by oxidation temperature zoning in three main regions which are moisture, unburned hydrocarbon (HC) and carbon. It is clearly observed that the amount of each region is strongly depending on engine operating condition, the amount of unburned HC in low load condition of the engine load are larger than that of high load condition. The calculated apparent activation energies of biodiesel PM oxidation are lower than that of diesel PM and carbon black because of unburned oxygenated molecule. The calculated apparent activation energy of biodiesel and diesel PMs oxidize with air is in the range of 147-157 kJ/mole and 153-165 kJ/mole, respectively. The results of this research would be used as basic information for design and develop removing process of particulate matter emitted from engine combustion which using in diesel and biodiesel fuels.

Are Accuracy Studies for Periprosthetic Joint Infection Diagnosis Inherently Flawed? And What to Do with Schrödinger’s Hips? A Prospective Analysis of the Alpha Defensin Lateral-Flow Test in Chronic Painful Hip Arthroplasties

( Jesse W.P. Kuiper ),( Steven J. Verberne ),( Pim W. van Egmond ),( Karin Slot ),( Olivier P.P. Temmerman ),( Constantijn J. Vos ) 대한고관절학회 2022 Hip and Pelvis Vol.34 No.4

Purpose: The most recent diagnostic criteria for periprosthetic joint infection (PJI) include the use of the alphadefensin (AD) lateral-flow (LF) test, but hip and knee arthroplasties were usually combined in previous studies. This prospective study was designed to examine the accuracy of the AD-LF test for diagnosis of PJI in chronic painful total hip arthroplasties (THA). Materials and Methods: Patients with chronic painful hip arthroplasties were prospectively enrolled between March 2018 and May 2020. Exclusion criteria included acute PJI or an insufficient amount of synovial fluid. The modified Musculoskeletal Infection Society (MSIS) criteria were primarily used for PJI diagnosis. Fifty-seven patients were included in the analysis group. Revision surgery was not performed in 38 patients, for different reasons (clinical group); these patients remain “Schrödinger’s hips”: in such cases PJI cannot be excluded nor confirmed until you “open the box”. Results: The result of the AD-LF test was positive in nine patients and negative in 48 patients. Six patients were diagnosed with PJI. AD-LF sensitivity (MSIS criteria) was 83% (95% confidence interval [CI] 36-100%) and specificity was 92% (95% CI 81-98%). The positive and negative predictive value were 56% and 98%, respectively. Conclusion: The AD test is useful in addition to the existing arsenal of diagnostic tools, and can be helpful in the decision-making process. Not all patients with chronical painful THA will undergo revision surgery. Consequently, in order to determine the reliable diagnostic accuracy of this test, future PJI diagnostic studies should include a second arm of “Schrödinger’s hips”.

Effect of intracanal medications on the interfacial properties of reparative cements

Pereira, Andrea Cardoso,Pallone, Mariana Valerio,Marciano, Marina Angelica,Cortellazzi, Karine Laura,Frozoni, Marcos,Gomes, Brenda P.F.A.,de Almeida, Jose Flavio Affonso,de Jesus Soares, Adriana The Korean Academy of Conservative Dentistry 2019 Restorative Dentistry & Endodontics Vol.44 No.2

Objectives: The purpose of the present study was to evaluate the effect of calcium hydroxide with 2% chlorhexidine gel (HCX) or distilled water (HCA) compared to triple antibiotic paste (TAP) on push-out bond strength and the cement/dentin interface in canals sealed with White MTA Angelus (WMTA) or Biodentine (BD). Materials and Methods: A total of 70 extracted human lower premolars were endodontically prepared and randomly divided into 4 groups according to the intracanal medication, as follows: group 1, HCX; group 2, TAP; group 3, HCA; and group 4, control (without intracanal medication). After 7 days, the medications were removed and the cervical third of the specimens was sectioned into five 1-mm sections. The sections were then sealed with WMTA or BD as a reparative material. After 7 days in 100% humidity, a push-out bond strength test was performed. Elemental analysis was performed at the interface, using energy-dispersive spectroscopy. The data were statistically analyzed using analysis of variance and the Tukey test (p < 0.05). Results: BD presented a higher bond strength than WMTA (p < 0.05). BD or WMTA in canals treated with calcium hydroxide intracanal medications had the highest bond strength values, with a statistically significant difference compared to TAP in the WMTA group (p < 0.05). There were small amounts of phosphorus in samples exposed to triple antibiotic paste, regardless of the coronal sealing. Conclusions: The use of intracanal medications did not affect the bond strength of WMTA and BD, except when TAP was used with WMTA.

Effect of intracanal medications on the interfacial properties of reparative cements

Andrea Cardoso Pereira,Mariana Valerio Pallone,Marina Angélica Marciano,Karine Laura Cortellazzi,Marcos Frozoni,Brenda P. F. A. Gomes,José Flávio Affonso de Almeida,Adriana de Jesus Soares 대한치과보존학회 2019 Restorative Dentistry & Endodontics Vol.44 No.2

Objectives: The purpose of the present study was to evaluate the effect of calcium hydroxide with 2% chlorhexidine gel (HCX) or distilled water (HCA) compared to triple antibiotic paste (TAP) on push-out bond strength and the cement/dentin interface in canals sealed with White MTA Angelus (WMTA) or Biodentine (BD). Materials and Methods: A total of 70 extracted human lower premolars were endodontically prepared and randomly divided into 4 groups according to the intracanal medication, as follows: group 1, HCX; group 2, TAP; group 3, HCA; and group 4, control (without intracanal medication). After 7 days, the medications were removed and the cervical third of the specimens was sectioned into five 1-mm sections. The sections were then sealed with WMTA or BD as a reparative material. After 7 days in 100% humidity, a push-out bond strength test was performed. Elemental analysis was performed at the interface, using energy-dispersive spectroscopy. The data were statistically analyzed using analysis of variance and the Tukey test (p < 0.05). Results: BD presented a higher bond strength than WMTA (p < 0.05). BD or WMTA in canals treated with calcium hydroxide intracanal medications had the highest bond strength values, with a statistically significant difference compared to TAP in the WMTA group (p < 0.05). There were small amounts of phosphorus in samples exposed to triple antibiotic paste, regardless of the coronal sealing. Conclusions: The use of intracanal medications did not affect the bond strength of WMTA and BD, except when TAP was used with WMTA.

The Antibiofilm Effect of Blueberry Fruit Cultivars Against Staphylococcus epidermidis and Pseudomonas aeruginosa

Karine Rigon Zimmer,Carlos H. Blum-Silva,André Luiz Kulkamp Souza,Márcia WulffSchuch,Flávio Henrique Reginatto,Cláudio Martin P. Pereira,Alexandre José Macedo,Claiton Leonetti Lencina 한국식품영양과학회 2014 Journal of medicinal food Vol.17 No.3

The antibiofilm and antibacterial properties against Pseudomonas aeruginosa and Staphylococcus epidermidis and chemical characterization of six hydroethanolic blueberry extracts (blueberry rabbiteye—Vaccinium virgatum) from different cultivars and means of propagation were investigated. The total flavonoid, anthocyanin, and phenolic contents were determined by specific and well-established methods. Among the cultivars, Briteblue showed the lowest content of all metabolites analyzed, while Bluegem showed the highest concentrations of these compounds. All the micropropagated cultivars presented the highest amounts of chlorogenic acid. The blueberry fruit extracts showed strong activity against S. epidermidis biofilm (up to 84% inhibition) without inhibiting bacterial growth. Likewise, Bluegem micropropagated extract, which had the highest anthocyanin, flavonoids, and phenolic compound content, demonstrated the highest S. epidermidis biofilm inhibitory effect. Finally, a linear correlation between the total phenolic content and the percentage of biofilm inhibition was observed.

REE behavior and sorption on weak acid resins from buffered media

James P. Bezzina,Mark D. Ogden,Ellen M. Moon,Karin L. Soldenhoff 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.59 No.-

Rare Earth Elements (REEs) are of great importance to modern day societies. Although abundant, concentration of REE minerals in ores are generally quite low, with high concentration of impurities. To counteract this, selective extraction processes must be undertaken. Selective adsorption of REE from buffered media solutions on Purolite S910 and Amberlite IRC86 weak acid resins has been studied. Batch experiments have been carried out on solutions containing a selection of REEs, Y3+, Fe3+ and Al3+ in unbuffered media, malic acid, formic acid, acetic acid, alanine and lactic acid to determine the best extracting media. Isotherm behavior and extraction kinetics of IRC86 were determined for acetic acid media, at the most effective pH that was determined to be 4.38. The isotherms were conducted for La3+, Sm3+, Er3+ and Y3+ determining extraction maxima of 0.29, 0.34, 0.49 and 0.60 mmol L−1, respectively, with adsorption energies increasing with the same trend. Kinetic experiments determined that mid REEs were the fastest adsorption, with light REEs and heavy REEs displaying similar half-lives and Y3+ measuring the smallest half-life out of the studied ions.

Wild birds and urban pigeons as reservoirs for diarrheagenic Escherichia coli with zoonotic potential

Clarissa A. Borges,Marita V. Cardozo,Livia G. Beraldo,Elisabete S. Oliveira,Renato P. Maluta,Kaline B. Barboza,Karin Werther,Fernando A. Ávila 한국미생물학회 2017 The journal of microbiology Vol.55 No.5

In order to describe the role of wild birds and pigeons in thetransmission of shiga toxigenic Escherichia coli (STEC) andenteropathogenic Escherichia coli (EPEC) to humans and otheranimals, samples were collected from cloacae and oropharynxof free-living wild birds and free-living pigeons. Two STEC(0.8%) and five EPEC strains (2.0%) were isolated from wildbirds and four EPEC strains (2.0%) were recovered from pigeons. Serogroups, sequence types (STs) and virulence genes,such as saa, iha, lpfAO113, ehxA, espA, nleB and nleE, detectedin this study had already been implicated in human and animaldiseases. Multidrug resistance (MDR) was found in 25.0%of the pigeon strains and in 57.0% of the wild bird strains;the wild birds also yielded one isolate carrying extended-spectrumβ-lactamases (ESBLs) gene blaCTX-M-8. The high variabilityshown by PFGE demonstrates that there are no prevalentE. coli clones from these avian hosts. Wild birds and pigeonscould act as carriers of multidrug-resistant STEC andEPEC and therefore may constitute a considerable hazard tohuman and animal health by transmission of these strainsto the environment.