26,752 research outputs found
Bioavailability of Cu and Zn in raw and anaerobically digested pig slurry
No full textThe impact of anaerobic digestion on the bioavailability of copper and zinc from pig slurry was assessed. Both chemical and biological approaches were used independently on raw slurry (RS) and anaerobically digested pig slurry (DS). This work, using ultracentrifugation pellets from the same pig slurry before and after an anaerobic treatment, confirmed that Cu and Zn behave differently in terms of bioavailability, and contrasting results were obtained by chemical and biological assessments. A chemical approach combined a preliminary study of the pH effect on particulate/dissolved metal partitioning, sequential extraction, and biochemical fractionation. This approach tended to show a lower mobility of metals from digested slurry (DS). A biological approach was carried out with Zea mays and Vicia faba to study Cu and Zn uptake in soil amended with RS or DS. This assay could not differentiate the two slurries
Calitatea vieţii pacienţilor cu spondiloartrită anchilozantă cu dereglări oculare
No full textConferinţa naţională în medicina internă din Republica Moldova cu participare internaţională, 19-20 mai 2011, Chişinău, Republica MoldovaSummary. Interrelation between disease severity index
with the quality of life of patients with spondiloartrită
spondylitis (AS) that involve alterations eye.Scopul lucrării: a determina interelaţia indicilor
severităţii maladiei cu calitatea vieţii pacienţilor cu
spondiloartrită anchilozantă (SA) ce implica alterări
oculare.
Material şi metode. În studiul clinic au fost
incluşi 72 de pacienţi cu diagnosticul cert de spondiloartrită
anchilozantă conform criteriilor Amor
şi New York, modificate în 1984. Pacienţii au fost
selectaţi în SCM „Sfânta Treime”, la Catedra „Medicină
Internă”, FR şi SC nr. 1, secţia „Reumatologie”
în perioada 2007-2009. Lotul de studiu (1A) a fost
format din 52 de pacienţi cu afectare oculară în
cadrul SA, lotul de control (1B ) – 20 de bolnavi cu
diagnosticul de spondilită anchilozantă fără afectare
oculară. Pacienţii incluşi în studiu au fost supuşi
cercetărilor clinice privind sindromul articular şi cel
extraarticular, care au inclus: numărul articulaţiilor
tumefiate; numărul articulaţiilor dureroase; evaluarea
severităţii bolii – indicii BASDAI, BASFI şi BASRI;
examenul oftalmologic. Au fost efectuate cercetări
paraclinice: teste biologice – hemoglobina, VSH,
PCR, Ag HLA-B27; examen radiologic al articulaţiilor afectate; examen funcţional USG, ECHOCG, ECG,
spirometria. Calitatea vieţii a fost evaluată conform
chestionarului „SF-36”. Datele obţinute au fost supuse
analizei statistice.
Rezultate. Conform datelor obţinute radiologic
a fost apreciată severiatatea bolii, folosind
scorul BASRI, care a fost mai pronunţat în grupul
1A de studiu – 8,96±2,14, comparativ cu 7,4±1,39 la
pacienţii din grupul 1B, cu diferenţă statistic concludentă
(p<0,01). Un alt indice al severităţii spondilitei
anchilozante este dizabilitatea funcţională, evaluată
prin calcularea indexului BASFI. Calcularea acestui
indice nu a relevat diferenţe statistic semnificative
între grupurile de studiu (p>0,05), dar am observat
predominarea unui scor mai înalt la pacienţii cu SA
cu manifestări oculare (BASFI – 6,87±2,27/6,15±2,02;
p>0,05). Un alt factor care determină severitatea SA
este activitatea maladiei. Activitatea SA a fost evaluată
calculând indicele BASDAI şi a fost completat
prin aprecierea markerilor de fază acută – PCR, VSH,
SVA şi redoarea matinală. Deşi diferenţe statistice
ale valorilor medii ale indicilor BASFI şi BASDAI între
grupuri nu au fost stabilite, totuşi, la pacienţii cu
SA şi manifestări oculare am observat valori medii
mai înalte ale acestor indici (p>0,05). Prezintă interes
valorile medii ale VSH – 28,07±4,46/21,95±3,14
(p<0,05), PCR – 1,69±1,1/1,08±0,63 (p<0,05), SVA
– 7,32±1,51/6,55±1,23 (p<0,05) şi ale redorii matinale
– 40,32±13,36/28,75±6,34 (p<0,05), care demonstrează
o activitate înaltă a spondilitei anchilozante
la pacienţii cu afectări oculare.
Concluzii. În baza interrelaţiei unor indici
clinici şi paraclinici cu calitatea vieţii pacienţilor,
am supus analizei corelaţionale Pearson parametrii:
vârsta, durerea (SVA), redoarea matinală,
indicii BASFI, BASDAI, BASRI şi indicele articular
SA, pentru a evidenţia influenţa acestora asupra
calităţii vieţii, atestate prin „SF-36”. Astfel, valoarea
dizabilităţii funcţionale „SF-36” a evidenţiat o corelare
indirectă medie cu vârsta r=-0,321, durerea
r =-0,488, redoarea matinală r=-0,379, indicele
BASDAI r =-0,566, indicele BASRI r=-0,438, indicele
articular SA r=-0,611 şi o corelare indirectă puternică
cu indicele BASFI r=-0,714. Folosind analiza de
regresie multiplă, am determinat că din toţi indicii
studiaţi cea mai mare influenţă asupra dizabilităţii
funcţionale, determinate prin „SF-36”, o au indicii:
BASFI şi MASES, cu un coeficient de determinaţie
R² = 0,581. O corelare directă medie a fost stabilită
între calitatea vieţii FF cu vârsta de r = 0,517, durerea
– r = 0,439, redoarea matinală – r = 0,623, indicele
BASRI – r = 0,624 şi o corelare directă puternică cu
indicele BASFI – r=0,782, indicele BASDAI – r=0,723
şi indicele articular SA – r=0,762
The impacts of social media on destination branding. Case study based on Hanoi city – the capital of Vietnam.
No full textThe purpose of the thesis was to discover the current situation of social media in destination branding with a use case of a developing city in Vietnam while weighing the impacts of social media marketing brings to advertise the destination.
In the theoretical chapters of the thesis, the author aimed to understand the general state of social media at the moment. Moreover, the author wanted to understand the impacts that social media has on the image of Hanoi. So that he could utilize the advantages and minimize the disadvantages affecting directly to the image of Hanoi. There were a few studies that only focus on the general picture of the relationship between social media marketing and destination branding. However, they did not concentrate on the specific purpose of the effectiveness of social media marketing in a destination. According to the data which was collected after six interviews, the author had an overview of the current impacts of social media marketing and the ways of improving them from the experts in this field.
Combined with previous studies, the influences of social media on the destination have been seen. Besides, there are more suitable proposals to improve and promote the image of Hanoi in the future. At the end chapter of the thesis, the author also gave a few pieces of advice as a guideline to build an effective social media marketing plan
Wettability of molten Sn-Bi-Cu solder on Cu substrate
No full textThe wetting behavior of a new Sn-Bi-Cu Pb-firee solder on Cu substrate was investigated by sessile drop method under an Ar-H(2) flow in the temperature range from 493 K to 623 K. The contact angle curves tested at 548 K and 623 K are found to fit exponential rule very well. However. the contact angle curve tested under493 K is not well consistent with exponential rule, for which the spreading course may be classified into three stages. Equilibrium contact angles between Sn-Bi-Cu solder and Cu substrate decrease monotonously with the increase in temperature, which are 28 degrees, 24 degrees and 18 degrees at 493 K. 548 K and 623 K, respectively. The results show that 69.5Sn30Bi-0.5Cu/exhibits good wettability on Cu substrate. Intermetallics formed at the 69.5Sn-30Bi-0.5Cu/Cu interface are identified as Cu(6)Sn(5) adjacent to the solder and Cu(3)Sn adjacent to the Cu substrate, respectively. Formation of intermetallic seems to improve strong wetting of the substrate by the solder. (C) 2009 Elsevier B.V. All rights reserved
Cu(II)-imprinted porous film adsorbent Cu-PVA-SA has high uptake capacity for removal of Cu(II) ions from aqueous solution
No full textIn this study, we prepared Cu(II)-imprinted porous film adsorbent Cu-PVA-SA and used it for adsorption Cu (II) ions from aqueous solution. The Cu-PVA-SA can be conveniently used without centrifugation or filtration methods. Copper adsorption on the surface of the Cu-PVA-SA was proved by FT-IR, SEM and EDX. To investigate the effects of experimental parameters on adsorption behavior, we performed a batch of experiments by changing the concentration of Cu(II) ions in the Cu-PVA-SA, the pH of the solution, contact time, adsorbent dosage, ionic strength and initial Cu(II) ion concentration. Our Cu-PVA-SA showed the maximum uptake of 79.3 mg/g under the optimal adsorption condition and has significantly higher uptake than that of nonimprinted PVA-SA. Interestingly, we found the uptake of the Cu-PVA-SA for Cu(II) ions decreased with an increasing of ionic strength, and the pH of the solution decreased with the increase of contact time until the adsorption equilibrium. Competitive adsorption studies for the binary system Cu(II)/Zn (II) and Cu(II)/Cd(II) suggested that the adsorption of Cu-PVA-SA for Cu(II) ions was preferable to Cd(II) and Zn(II) ions. Kinetics experiments indicated the pseudo-second-order model displayed the best correlation with our data. Besides, our equilibrium data could be better described by the Freundlich isotherm model. (C) 2011 Elsevier B.V. All rights reserved.National Natural Science Foundation of China[21076174]; Fujian Education Department Foundation (type A)[JA 10206]; Zhangzhou Normal University Foundation[2003 L20926
Ordering of organic molecules on templated surfaces
No full textThis thesis describes the controlled growth of molecular nanostructures using modified metallic and semiconductor surfaces. The Ag/Si(lll)-(root3 x root3),the Sn/Cu(100) surface alloy system and the Bi/Si(100) nanolines and (2xn) surfaces were all investigated as suitable substrates for the controlled growth of pentacene, (C22H14) or trimesic acid, (C6H3(COOH)3) organic molecules. The following techniques were used in this study; Scanning Tunnelling Microscopy (STM), Low Energy Electron Diffraction (LEED), Normal Incident X-Ray Standing Waves (NIXSW) and Temperature Programmed Desorption (TPD).
The room temperature growth and ordering of trimesic acid on the AgfSi(ll1)-(root3 x root3) surface was investigated. An oblique unit cell was determined and a model proposed for the highly ordered close-packed domains.
The discovery of a new submonolayer phase on Sn/Cu(100) and the re-examined known phase are discussed. New models for these reconstructions are proposed. Adsorption of trimesic acid at room temperature on the clean substrate the lowest Sn coverage phase were studied. Two new Sn coverage dependent structures were discovered and bonding schemes in upright and flat orientations are discussed.
BifSi(100)-(2xn) surface was exploited as a template for the ordered growth of pentacene, which exhibited orientation specific adsorption. The Bi/Si(100)-(2xn) single domain surface created on vicinal silicon was used to test the suitable of Daresbury 4.2 beamline for NIXSW Imaging experiments and the quality of the results are discussed
Emulsion polymerization of tetrafluoroethylene: effects of reaction conditions on particle formation
No full textThe emulsion polymerization of TFE was carried out with a surfactant (FC-143) and an initiator (ammonium persulfate) under various reaction conditions. Two different shapes of PTFE dispersion particles were produced by the emulsion polymerization, rods and spherical particles. Variables, except for surfactant concentration, do not affect the initial and final particle morphology when no coagulation occurs. Rod-like particles are formed when the surfactant concentration is near or above the critical micelle concentration (CMC) of the surfactant. At below CMC, however, spherical particles are dominant. No hexagon-shaped particles or abrupt changes in the particle morphology are observed during polymerization. When no coagulation occurred, the size and number of polymer particles suddenly increased in the early stages of emulsion polymerization and then steadily increased as time progressed. Most particles are formed in the early stages (within 5 min), and the size of particles formed was in the range 60-80 nm in diameter. The particle sizes ranged from 100 to 230 nm at 250 g/l of a specific TFE uptake concentration (the PTFE dispersion had a solid content of about 20%). It was found that the size and number of polymer particles formed are almost independent of the temperature, pressure, concentration of initiator and stabilizer (anti-coagulant), whereas the surfactant concentration, kinds of stabilizer, and agitation speed are important. The particle size decreased gradually as the dispersion concentration increased, whereas the particle number increased exponentially. When the PTFE dispersion coagulated during polymerization under certain conditions (high temperature and agitation speed, and low concentration of surfactant), the particle size suddenly increased, the particle number suddenly decreased, and the rate of the polymerization decreased, indicating that the polymerization occurred on the surface of the polymer particles. (C) 1999 Elsevier Science S.A. All rights reserved
Nanoindentation investigation on creep behavior of amorphous Cu-Zr-AI/nano crystalline Cu nanolaminates
No full textBerkovich nanoindentation experiments have been performed on amorphous /nanocrystalline nanolaminates with individual Cu-Zr-Al layers (45 nm 90 nm 225 nm) and Cu layers (7.5 nm & 15 nm). Elastic modulus hardness and indentation morphology were detected and compared to those of single Cu-Zr-Al thin film. Creep deformation was systematically investigated at various holding depths and loading rates. For the sample with thinner amorphous layer a more pronounced creep deformation was observed and it was confirmed to be due to the size effect of Cu-Zr-Al layers and the addition of Cu layers. The creep deformation was identified to be history-independent through applying various loading rates. The strain rate sensitivities were calculated from the steady-state creep and a sharp enlargement appeared as the amorphous layer reduced down to 90 nm implying a transition of creep mechanism in nanolaminates. (C) 2017 Elsevier B.V. All rights reserved
Crisis Inversion Strategies – Theory or Reality in Romania of 2009?
No full textThe world crisis has begun showing its effects in Romania in October 2008. Still, the immaturity of Romanian authorities in the political and economic fields, as well as the enthusiasm of economic development led to an unconscious state of mind regarding the crisis. Therefore, Romanian companies have not started preparing for the crisis until they began feeling its effects. Also, a large number of Romanian managers are not familiar with crisis inversion strategies and accept crisis as an invincible necessity. Still, in other economies we can find examples of managers who fight for saving their companies and even try gaining competitive advantage based on the crisis. We have tried to find out if Romanian managers belong to the second type. ainly, the study focuses on strategies adopted by Romanian companies in order to counterbalance or, at least, ensure their survival during the world crisis.crisis, Romania, strategy, inversion
Cu isotopic compositions in Elsholtzia splendens: Influence of soil condition and growth period on Cu isotopic fractionation in plant tissue
No full textThis study investigates the magnitude and direction of Cu isotopic fractionation in the Cu-tolerant, strategy I plant, Elsholtzia splendens, considering the effect of soil condition and plant growth cycle. Uptake of Cu by E. splendens from soil was found to favor light Cu isotopic enrichment (delta Cu-65 < 0 parts per thousand) due to reduction at the soil root interface. The magnitude of fractionation between soil and plant was found to be dependent on free Cu ion species in soil solution correlated with pH value of soil other than the phytoavailable component of soil or total soil for the same parent soil
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