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1.
Phys Rev E ; 101(2-1): 023203, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32168642

ABSTRACT

Third-order transport coefficient tensor of charged-particle swarms in neutral gases in the presence of spatially uniform electric and magnetic fields is considered using a multiterm solution of Boltzmann's equation and Monte Carlo simulation technique. The structure of the third-order transport coefficient tensor and symmetries along its individual components in varying configurations of electric and magnetic fields are addressed using a group projector technique and through symmetry considerations of the Boltzmann equation. In addition, we focus upon the physical interpretation of the third-order transport coefficient tensor by considering the extended diffusion equation which incorporates the contribution of the third-order transport coefficients to the density profile of charged particles. Numerical calculations are carried out for electron and ion swarms for a range of model gases with the aim of establishing accurate benchmarks for third-order transport coefficients. The effects of ion to neutral-particle mass ratio are also examined. The errors of the two-term approximation for solving the Boltzmann equation and limitations of previous treatments of the high-order charged-particle transport properties are also highlighted.

2.
Hum Exp Toxicol ; 38(6): 632-645, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30784321

ABSTRACT

In 2012, alcohol liver disease resulted in 3.3 million-5.9% of global deaths. This study introduced whey protection capacity against chronic alcohol-induced liver injury. Rats were orally administered to 12% ethanol solution in water (ad libitum, average 8.14 g of ethanol/kg body weight (b.w.)/day) alone or combined with whey ( per os, 2 g/kg b.w./day). After 6-week treatment, chronic ethanol consumption induced significant histopathological liver changes: congestion, central vein dilation, hepatic portal vein branch dilation, Kupffer cells hyperplasia, fatty liver changes, and hepatocytes focal necrosis. Ethanol significantly increased liver catalase activity and glutathione reductase protein expression without significant effects on antioxidative enzymes: glutathione peroxidase (GPx), copper-zinc-containing superoxide dismutase (CuZnSOD) and manganese-containing superoxide dismutase (MnSOD). Co-treatment with whey significantly attenuated pathohistological changes induced by ethanol ingestion and increased GSH-Px and nuclear factor kappa B (NF-κB) protein expression. Our results showed positive effects of whey on liver chronically exposed to ethanol, which seem to be associated with NF-κB-GPx signaling.


Subject(s)
Chemical and Drug Induced Liver Injury, Chronic/drug therapy , Liver Diseases, Alcoholic/drug therapy , Protective Agents/therapeutic use , Whey , Alcohol Drinking , Animals , Chemical and Drug Induced Liver Injury, Chronic/metabolism , Chemical and Drug Induced Liver Injury, Chronic/pathology , Glutathione Peroxidase/metabolism , Liver/drug effects , Liver/pathology , Liver Diseases, Alcoholic/metabolism , Liver Diseases, Alcoholic/pathology , Male , NF-kappa B/metabolism , Protective Agents/pharmacology , Rats, Wistar
3.
J Hosp Infect ; 98(2): 149-154, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28951069

ABSTRACT

BACKGROUND: The costs and laboratory workload arising from meticillin-resistant Staphylococcus aureus (MRSA) screening could be reduced markedly by processing nose, throat and skin swabs from one person in a single culture broth (specimen pooling). The purpose of this study was to evaluate the sensitivities and times for MRSA detection using a variety of approaches to processing of individual and pooled swabs. METHODS: Four hundred and seventeen swabs from 139 subjects with a history of MRSA colonization (three swabs per subject - nose, throat and skin) were submitted. Swabs were suspended in 200-µL sterile saline, and these suspensions were used individually and as pooled samples to inoculate two different chromogenic media [MRSA SMART (bioMerieux, Marcy-l'Étoile, Paris, France) and CHROMagar MRSA (CHROMagar, Paris, France)] and Todd-Hewitt Broth; the latter cultures were then subcultured on to the same chromogenic media. RESULTS: MRSA was detected from at least one specimen in 75 subjects (50.4%). The diagnostic sensitivities of pooled surveillance cultures compared with single cultures were 97% and 93% for direct and enrichment cultures, respectively. Enrichment culture of either individual or pooled samples had no benefit compared with direct culture (P>0.05). CONCLUSIONS: Pooling of MRSA screening swabs for either direct culture on chromogenic agar or enrichment culture is suitable for routine use.


Subject(s)
Carrier State/diagnosis , Mass Screening/methods , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Specimen Handling/methods , Staphylococcal Infections/diagnosis , Adult , Aged , Aged, 80 and over , Bacteriological Techniques/methods , Carrier State/microbiology , Female , Humans , Male , Middle Aged , Nose/microbiology , Pharynx/microbiology , Sensitivity and Specificity , Skin/microbiology , Staphylococcal Infections/microbiology , Time Factors
4.
Article in English | MEDLINE | ID: mdl-27717290

ABSTRACT

Mycotoxins are a group of naturally occurring toxic chemical substances, produced mainly by microscopic filamentous fungal species. Regarding potential synergisms or even mitigating effects between toxic elements, mycotoxin contamination will continue to be an area of concern for producers, manufacturers, regulatory agencies, researchers, and consumers in the future. In Serbia, recent drought and then flooding confirmed that mycotoxins are one of the foodborne hazards most susceptible to climate change. In this article, we review key aspects of mycotoxin contamination of the food supply chain and implications for public health from the Serbian perspective.


Subject(s)
Food Contamination/analysis , Food Supply , Hazardous Substances/analysis , Mycotoxins/analysis , Climate Change , Food Chain , Food Contamination/statistics & numerical data , Public Health , Risk Assessment , Serbia
5.
Clin Otolaryngol ; 41(6): 634-639, 2016 Dec.
Article in English | MEDLINE | ID: mdl-26493548

ABSTRACT

OBJECTIVE: To evaluate the efficacy of bilateral selective neck dissection of levels II-IV in elective and therapeutic management of the neck as a part of primary surgical treatment of patients with supraglottic laryngeal cancer and clinically negative cervical findings (N0). DESIGN: Institutional, observational, case-control study with historic control of patients who underwent primary supraglottic tumour surgery, and a prospective cohort of patient, who underwent, besides the operation of primary tumour, bilateral selective neck dissection (level II-IV). SETTING: University, tertiary level hospital, national referral centre. PARTICIPANTS: The study included 193 patients with supraglottic cancer and without palpable or ultrasound positive cervical findings who were surgically treated from 1988 to 2005. Besides the operation of primary tumour, all patients in the study group underwent bilateral selective neck dissection (level II-IV). Patients in the control group (N = 51) underwent primary tumour operation only and were followed up regularly. In cases with postoperative regional recurrences, the radical neck dissection was performed. All patients with histopathological confirmation of occult metastases were administered radiotherapy treatment (60 Gy) in the postoperative period. MAIN OUTCOME MEASURES: Five-year overall survival rate. RESULTS: Occult cervical metastases were found in 18% of patients. They were present in level II in 77.5%, in level III in 20% of cases and in one patient in level IV (2.5%); the extracapsular spread was observed in 20% of cases. Postoperative regional metastases were found in 4.15% of cases in the study group, and in 11.8% in the control group, which proved to be significantly higher. The five-year overall survival rate showed no significant difference between the study group and the control group. CONCLUSION: The incidence of postoperative regional recurrences could be reduced by performing bilateral selective neck dissection simultaneously with primary tumour operation, but with no influence on the survival rate.


Subject(s)
Carcinoma/pathology , Carcinoma/surgery , Laryngeal Neoplasms/pathology , Laryngeal Neoplasms/surgery , Neck Dissection , Adult , Aged , Carcinoma/mortality , Case-Control Studies , Female , Humans , Laryngeal Neoplasms/mortality , Laryngectomy , Male , Middle Aged , Prospective Studies , Survival Rate , Treatment Outcome
6.
Sci Rep ; 5: 12674, 2015 Aug 06.
Article in English | MEDLINE | ID: mdl-26246002

ABSTRACT

The kinetic theory of non-relativistic positrons in an idealized positron emission tomography PET environment is developed by solving the Boltzmann equation, allowing for coherent and incoherent elastic, inelastic, ionizing and annihilating collisions through positronium formation. An analytic expression is obtained for the positronium formation rate, as a function of distance from a spherical source, in terms of the solutions of the general kinetic eigenvalue problem. Numerical estimates of the positron range - a fundamental limitation on the accuracy of PET, are given for positrons in a model of liquid water, a surrogate for human tissue. Comparisons are made with the 'gas-phase' assumption used in current models in which coherent scattering is suppressed. Our results show that this assumption leads to an error of the order of a factor of approximately 2, emphasizing the need to accurately account for the structure of the medium in PET simulations.


Subject(s)
Electrons , Models, Theoretical , Positron-Emission Tomography/methods
7.
Int J Med Microbiol ; 305(6): 505-10, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26055648

ABSTRACT

The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in Slovenia is poorly documented. The aim of this study was to investigate susceptibility patterns, virulence gene profile and clonality among MRSA isolates with positive screened resistance phenotype for CA-MRSA collected from patients in Slovenia, from January 2010 to December 2010. We included only MRSA isolates that were resistant to cefoxitin and oxacillin, and susceptible to at least two of the following four antibiotics: ciprofloxacin, erythromycin, clindamycin or gentamicin (presumptive CA-MRSA). Altogether 151 isolates fulfilled our screening phenotypic definition, 126 MRSA isolates were classified as CA-MRSA and 25 as HA-MRSA. Thirty-six per cent of them were resistant to ciprofloxacin, 24% to clindamycin, 33% to erythromycin and 13% to gentamicin. The mecA gene was detected in 150 isolates, while the mecC gene only in 1 isolate. The MRSA isolates were classified to 19 different clones. The most prevalent sequence types were ST5 (26.4%), ST45 (25.2%), ST22 (10.6%), ST398 (9.9%), ST8 (5.9%), ST7 (4.6%), ST1 (3.9%), ST152/377 (3.3%), ST228 (2.6%) and ST2883 (1.3%). The ST6, ST9, ST30, ST72, ST88, ST111, ST130, ST225 and ST772 were identified sporadically. The Panton-Valentine leukocidin (PVL) gene was detected in 13 (8.6%) isolates that belonged to ST5, ST7, ST8, ST22, ST72, ST88, ST 152/377 and ST772. Our results show high variability of CA-MRSA circulating in Slovenia and also the presence of LA-MRSA clones.


Subject(s)
Livestock/microbiology , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Animals , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacterial Toxins/genetics , Ciprofloxacin/pharmacology , Clindamycin/pharmacology , Cloning, Molecular , Drug Resistance, Multiple, Bacterial , Erythromycin/pharmacology , Exotoxins/genetics , Gentamicins/pharmacology , Leukocidins/genetics , Methicillin-Resistant Staphylococcus aureus/genetics , Microbial Sensitivity Tests , Microbial Viability , Penicillin-Binding Proteins/genetics , Penicillin-Binding Proteins/metabolism , Slovenia
8.
Acta Clin Belg ; 70(6): 408-13, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26790552

ABSTRACT

OBJECTIVES: Aim of the study was to investigate the effects of 1-year therapy by different proton pump inhibitors (PPIs) on epithelial tissue and surrounding inflammatory changes in Barrett's oesophagus, in patients who have abandoned invasive therapy. METHODS: A group of 120 patients (sampled in 60-month period, from 61201 upper gastrointestinal endoscopies) who were diagnosed both, endoscopically and pathohistologically with Barrett's oesophagus, and who have abandoned invasive therapeutic approach were enrolled in study. Treatment with different PPIs was initiated and continued for a year. At the end of treatment, patients were reassessed by endoscopy with tissue biopsy and pathohistological analysis. RESULTS: No difference in regenerating squamous epithelium or degree of dysplasia was seen between different treatment groups. Interestingly, most patients receiving pantoprazole (94%) ended up with thinner squamous epithel (P<0.0001). The squamous epithel was consider thinner only if its total thickness, measured on histological specimen, was smaller for more than 50% of the thickness before therapy. Significantly less of difference (P<0.0014) was seen with patients receiving lansoprazole (65%) and (P<0.003) omeprazole (50%). CONCLUSION: Regeneration of the squamous epithel was the same for all PPIs but not good enough to stop the progression of the disease.


Subject(s)
Barrett Esophagus/drug therapy , Esophagus/drug effects , Proton Pump Inhibitors/administration & dosage , 2-Pyridinylmethylsulfinylbenzimidazoles/administration & dosage , Barrett Esophagus/pathology , Epithelial Cells/cytology , Esophagoscopy , Esophagus/pathology , Humans , Lansoprazole/administration & dosage , Omeprazole/administration & dosage , Pantoprazole
9.
Appl Radiat Isot ; 83 Pt B: 77-85, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23395226

ABSTRACT

We present a study of electron and positron transport in water in both the gaseous and liquid states using a Boltzmann equation analysis and a Monte-Carlo simulation technique. We assess the importance of coherent scattering processes when considering transport of electrons/positrons in dense gases and liquids. We highlight the importance of electron and positron swarm studies and experiments as a test of the accuracy and completeness of cross-sections, as well as a technique for benchmarking Monte-Carlo simulations. The thermalization of low-energy positrons (<150 eV) in water is discussed and the sensitivity of the profiles to the form of the cross-sections in this energy region, and assumptions in the microscopic processes, is considered.


Subject(s)
Electrons , Gases/chemistry , Models, Theoretical , Monte Carlo Method
10.
Tech Coloproctol ; 17(5): 541-7, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23619713

ABSTRACT

BACKGROUND: Anastomotic leakage (AL) represents a serious complication after abdominal surgery. Therefore, it is important to detect it early before it becomes clinically apparent. The predictive value of C-reactive protein (CRP) as a marker of infective postoperative complications, particularly in the form of anastomotic leakage, has been investigated by several authors with promising results. The aim of this study was to evaluate the diagnostic accuracy of C-reactive protein in predicting anastomotic leakage. METHODS: The serum CRP level, white blood cell (WBC) count, and body temperature (BT) of 156 patients who underwent elective abdominal surgery with primary anastomosis were monitored daily until postoperative day (POD) 7. We recorded all postoperative complications and analyzed the data. Diagnostic accuracy of CRP with regard to development of AL was assessed by receiver operating characteristic curve analysis. RESULTS: Fifteen patients (9.6 %) developed anastomotic leakage. CRP was significantly higher every day during the first 7 postoperative days in patients who developed AL compared with those patients who did not develop complications, whereas the WBC count and BT were not. A CRP cutoff value of 135 mg/l on POD 3 yielded a sensitivity of 73 %, a specificity of 73 %, and a negative predictive value of 95.4 % for the detection of AL. CONCLUSIONS: According to our results, values of CRP less than 135 mg/l on POD 3 may contribute to a safe discharge from hospital. Patients with CRP values higher than 135 mg/l on POD 3 require prolonged hospitalization and an intensive search for infective complications, particularly AL.


Subject(s)
Anastomotic Leak/blood , C-Reactive Protein/analysis , Digestive System Surgical Procedures/adverse effects , Elective Surgical Procedures , Gastrointestinal Diseases/surgery , Surgical Wound Infection/blood , Adult , Aged , Aged, 80 and over , Anastomosis, Surgical/adverse effects , Anastomosis, Surgical/methods , Anastomotic Leak/diagnosis , Anastomotic Leak/epidemiology , Area Under Curve , Biomarkers/blood , Cohort Studies , Digestive System Surgical Procedures/methods , Female , Follow-Up Studies , Gastrointestinal Diseases/pathology , Humans , Leukocyte Count , Male , Middle Aged , Predictive Value of Tests , ROC Curve , Retrospective Studies , Risk Assessment , Sensitivity and Specificity , Surgical Wound Infection/diagnosis , Surgical Wound Infection/epidemiology , Treatment Outcome
11.
J Laryngol Otol ; 126(5): 516-24, 2012 May.
Article in English | MEDLINE | ID: mdl-22449728

ABSTRACT

OBJECTIVE: This study aimed to compare the prognostic impact of comorbidity grading by the Adult Comorbidity Evaluation 27 index and the Charlson Comorbidity Index on the five-year overall and disease-specific survival in patients undergoing surgery for laryngeal squamous cell carcinoma. METHODS: The impact of comorbidity and other factors on survival was examined retrospectively in a group of 177 patients with previously untreated tumour stage one to four laryngeal squamous cell carcinoma surgically treated at the Clinic of Otorhinolaryngology and Maxillofacial Surgery, Clinical Centre of Serbia, between 2000 and 2003. The Cox proportional hazard model was used to identify independent prognostic factors. RESULTS: On univariate analysis, comorbidity had an impact on prognosis regardless of which index was used. On multivariate analysis, the significant predictors of patients' five-year overall and disease-specific survival were tumour-node-metastasis stage and comorbidity as graded by the Adult Comorbidity Evaluation 27 index. CONCLUSION: The Adult Comorbidity Evaluation 27 index is a more reliable predictor of survival than the Charlson Comorbidity Index in patients with laryngeal squamous cell carcinoma.


Subject(s)
Carcinoma, Squamous Cell/epidemiology , Comorbidity , Health Status Indicators , Laryngeal Neoplasms/epidemiology , Adult , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/pathology , Female , Humans , Laryngeal Neoplasms/mortality , Laryngeal Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Prognosis , Retrospective Studies , Severity of Illness Index , Survival Analysis
12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(5 Pt 2): 055401, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22181466

ABSTRACT

In this paper investigations of the voltage required to break down water vapor are reported for the region around the Paschen minimum and to the left of it. In spite of numerous applications of discharges in biomedicine, and recent studies of discharges in water and vapor bubbles and discharges with liquid water electrodes, studies of the basic parameters of breakdown are lacking. Paschen curves have been measured by recording voltages and currents in the low-current Townsend regime and extrapolating them to zero current. The minimum electrical breakdown voltage for water vapor was found to be 480 V at a pressure times electrode distance (pd) value of around 0.6 Torr cm (~0.8 Pa m). The present measurements are also interpreted using (and add additional insight into) the developing understanding of relevant atomic and particularly surface processes associated with electrical breakdown.


Subject(s)
Biomedical Engineering/methods , Biophysics/methods , Steam , Water/chemistry , Electricity , Electrodes , Equipment Design , Gases , Ions , Pressure
13.
Parasite ; 18(2): 189-96, 2011 May.
Article in English | MEDLINE | ID: mdl-21678796

ABSTRACT

SUMMARY: Gastrointestinal helminths of Norway rat (Rattus norvegicus) from the Belgrade area were studied as a part of a wider ecological research of rats in Serbia (data on the distribution, population ecology, economic and epizoothiological-epidemiological importance, and density control). Rats were captured from May 2005 to July 2009 at both urban and suburban-rural sites. Of a total of 302 trapped rats 48% were males and 52% females, with 36.5% and 38.8% of juvenile-subadult individuals, per sex respectively. Intestinal helminth infection was noted in 68.5% of rats, with a higher prevalence in male hosts and in adult individuals. Higher numbers of infected juveniles-subadults were noted in suburban-rural habitats, while an opposite tendency was noted in adult rats. Seven helminth species were recovered, of which five were nematode (Heterakis spumosa, Nippostrongylus brasiliensis, Capillaria sp., Trichuris muns and Syphacia muris) and two cestode species (Hymenolepis diminuta and Rodentolepis fraterna). The most prevalent parasites were Heterakis spumosa (36.7%) and Hymenolepis diminuta (30.5 %). Sex and habitat-related differences were noted in the prevalence of infection with Capillaria sp. and Trichuris muris, while there were no age-related differences in the prevalence of infection with any individual helminth species. Significantly higher prevalence of infection was noted in summer as compared to spring or winter, with a tendency to be higher in autumn as compared to spring. The only significant difference in the prevalence of infection between habitat-related was noted during spring. H. spumosa was most prevalent in summer, while H. diminuta and N. brasiliensis in autumn. The mean intensity of infection with H. spumosa, R. fraterna, S. muris and T muris was higher in autumn than in the other seasons, while N. brasiliensis and Capillaria sp. occured in winter. No more than four helminth species were found in one host.


Subject(s)
Helminthiasis, Animal/epidemiology , Intestinal Diseases, Parasitic/veterinary , Rats/parasitology , Rodent Diseases/epidemiology , Rodent Diseases/parasitology , Animals , Ecosystem , Female , Helminthiasis, Animal/parasitology , Intestinal Diseases, Parasitic/epidemiology , Intestinal Diseases, Parasitic/parasitology , Male , Prevalence , Rural Population , Seasons , Serbia/epidemiology , Sex Distribution , Urban Population
14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 81(4 Pt 2): 046403, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20481843

ABSTRACT

A multiterm solution of the Boltzmann equation has been developed and used to calculate transport coefficients of charged-particle swarms in gases under the influence of electric and magnetic fields crossed at arbitrary angles when nonconservative collisions are present. The hierarchy resulting from a spherical-harmonic decomposition of the Boltzmann equation in the hydrodynamic regime is solved numerically by representing the speed dependence of the phase-space distribution function in terms of an expansion in Sonine polynomials about a Maxwellian velocity distribution at an internally determined temperature. Results are given for electron swarms in certain collisional models for ionization and attachment over a range of angles between the fields and field strengths. The implicit and explicit effects of ionization and attachment on the electron-transport coefficients are considered using physical arguments. It is found that the difference between the two sets of transport coefficients, bulk and flux, resulting from the explicit effects of nonconservative collisions, can be controlled either by the variation in the magnetic field strengths or by the angles between the fields. In addition, it is shown that the phenomena of ionization cooling and/or attachment cooling/heating previously reported for dc electric fields carry over directly to the crossed electric and magnetic fields. The results of the Boltzmann equation analysis are compared with those obtained by a Monte Carlo simulation technique. The comparison confirms the theoretical basis and numerical integrity of the moment method for solving the Boltzmann equation and gives a set of well-established data that can be used to test future codes and plasma models.

15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(1 Pt 2): 016408, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19658824

ABSTRACT

Spatial distributions of H alpha , H beta , and the near-uv continuum emission from the H2 a ;{3}Sigma g;+ state are measured and compared with a model for low-current electrical discharges in H2 at high E/N and low Nd , where E is the spatially uniform electric field, N is the gas density, and d is the electrode separation. Data are analyzed for 300 Td

16.
Acta Chir Iugosl ; 56(3): 117-20, 2009.
Article in Serbian | MEDLINE | ID: mdl-20218115

ABSTRACT

The treatment of patients with supraglottic laryngeal cancer still remains a controversal issue. The study comprised 193 patients with a supraglottic laryngeal carcinoma treated in the period 1986-2003. All patients had primary surgery. They all had clinically and ultrasonografically negative findings in the neck (N0). Bilateral selective neck dissection at the level II-III was performed in all patients at the time of primar surgery. Postoperative radiotherapy was given to all patients with verified occult metastases (60 Gy). The occult cervical node metastases were found in 18% (35/193). Ipsilateral occult metastases were more common (77%, 27/35), but both bilateral and contralateral spread was also seen (14%, 5/35 and 9%, 3/35, respectively). Only in two (1%) did metastases develop subsequently. The 5-years survival rate was 86%.


Subject(s)
Laryngeal Neoplasms/pathology , Lymphatic Metastasis , Neck Dissection , Adult , Aged , Female , Humans , Laryngeal Neoplasms/surgery , Male , Middle Aged
17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(6 Pt 2): 066401, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20365280

ABSTRACT

Absolute spectral emissivities for Doppler broadened H(alpha) profiles are measured and compared with predictions of energetic hydrogen ion, atom, and molecule behavior in low-current electrical discharges in H2 at very high electric field E to gas density N ratios E/N and low values of Nd , where d is the parallel-plate electrode separation. These observations reflect the energy and angular distributions for the excited atoms and quantitatively test features of multiple-scattering kinetic models in weakly ionized hydrogen in the presence of an electric field that are not tested by the spatial distributions of H(alpha) emission. Absolute spectral intensities agree well with predictions. Asymmetries in Doppler profiles observed parallel to the electric field at 4

18.
Commun Agric Appl Biol Sci ; 72(2): 35-43, 2007.
Article in English | MEDLINE | ID: mdl-18399422

ABSTRACT

Polyurethanes prepared from vegetable oils display a number of desirable properties useful for many commercial and industrial applications. One unique application is that of an agricultural seed treatment. Seed treatments are used to incorporate pesticides onto the seed coat and to decrease the disease susceptibility of the seed during its germination in the soil. In addition, by altering the movement of water across the seed coat and by incorporating protective pesticides in the coating, seed coating polymers can enhance the germination and survival of the seed under adverse environmental conditions. Soy polyols alone, and in combination with glycerin, polymerized with 4,4'-diphenylmethane diisocyanate (MDI) were studied for their seed treating properties and impact on soybean seed germination. The cross-linking density and properties of these polyurethane compounds were varied by changing the isocyanate/hydroxyl molar ratios. In order to optimize the coating qualities and to increase the efficiency of the coating, acetone was also studied as a diluting solvent to reduce the viscosity of the polyurethane mixture prior to polymerization on the seed coat. Optimal polymerization and resulting germination (95%) were obtained using a 1:1 isocyanate/hydroxyl molar ratio consisting of a mixture of soy polyol 180 and glycerin, and the use of an equal volume of acetone as a dilution solvent. This optimal polyurethane seed treatment had several desirable qualities including: reduced viscosity, decreased seed coating thickness, increased seed coating uniformity and permitted larger volumes of seed to be treated with the same volume of polymer. This optimal seed treatment increased the soybean seed germination by 15%, as compared with untreated seed. In addition, preliminary studies of the compatibility of these unique formulations with commercial and experimental fungicides also support the use of these polymers as seed treatments due to their enhanced stability, longevity and slow active ingredient water teaching characteristics. Compatibility of these seed coating polymers as formulations with captan, metalaxyl, thiabendazole and novel antimicrobial lipids and triterpenoid compounds display that the active ingredients can readily provide a zone of fungal inhibition around the seed as it germinates in the presence of Macrophomina phaseolino, causal agent of charcoal rot of soybeans. However, the release of the active ingredient from the polyol seed treatments is less affected by water leaching as compared to commercially available water-soluble seed treating polymer formulations. This is most likely due to the polyols unique polymer cross-linking characteristics. These results support the continued exploration of soy polyol derived polymers as seed coating compounds.


Subject(s)
Germination/physiology , Glycine max/physiology , Pesticides/pharmacology , Polymers/chemistry , Seeds/physiology , Germination/drug effects , Glycerol/chemistry , Isocyanates/chemistry , Plant Diseases/microbiology , Seedlings/drug effects , Seedlings/growth & development , Seeds/chemistry , Seeds/growth & development , Glycine max/chemistry , Glycine max/growth & development , Viscosity
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 74(2 Pt 2): 026406, 2006 Aug.
Article in English | MEDLINE | ID: mdl-17025549

ABSTRACT

In this paper we present measurements of the secondary electron emission yield (gamma) of a carbonaceous dust particle material, which was grown in argon diluted acetylene plasmas. One aim was to reach a better understanding of charging and discharging processes of dust particles in complex plasmas due to secondary electron emission and consequently to try to explain the anomalous behavior of electron density observed in afterglows of pulsed rf plasmas. We compared the results of a simple model and of a Monte Carlo simulation to the previously measured time dependence of the electron density in complex plasma afterglow. It was found that the value of the intrinsic secondary electron yield from the carbonaceous dust material is too low to explain the increase of electron density in the afterglow. It is, however, possible that the electrons charging the particles are weakly attached so that they may be released with high efficiency by ion bombardment due to field induced emission or by other mechanisms.

20.
Acta Chir Iugosl ; 53(3): 79-82, 2006.
Article in English | MEDLINE | ID: mdl-17338205

ABSTRACT

Authors analysed 15 cases with visceral metastasis of melanoma. In eight cases the primary was unknown but in seven cases the data about primary was known. From 15 patients 10 were male and 5 female. All metastases were in abdominal cavity (liver-3, abdominal lymph nodes-4. stomach-2, bowel-4, omentum-1, spleen-1, oesophagus-1, adrenal-2 cases. In one case metastatic deposit was in brain and in one case i the vertebral body. In 6 cases visceral metastases were in more than one location.


Subject(s)
Abdominal Neoplasms/secondary , Melanoma/secondary , Neoplasms, Unknown Primary , Skin Neoplasms/pathology , Viscera , Adult , Aged , Female , Humans , Male , Middle Aged
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