Micro-image Analysis Research Articles

Synthesis of cordierite foam ceramics from kyanite tailings and simulated application effects

Cordierite foam ceramics (CFCs) were prepared using kyanite tailings (KT) and other polishing materials to demonstrate a resourceful application of KT. The reaction mechanism of KT, talc, and clay, which results in the formation of CFCs, was identified. The properties and structures of specimens can be optimised by adjusting the amount of foam and the heat treatment temperature. The effects of the amount of foam and the heat treatment temperature on the properties of CFCs, such as the compressive strength, porosity, bulk density, water absorption, and thermal conductivity, were investigated. The Micro-Image Analysis and Process System (MIAPS) software was used to measure the pore characteristics of the samples. The Comsol software was used to simulate the dynamic heat transfer changes of exterior building wall facades with cordierite foam ceramic insulation throughout the day in different seasons. The simulation data provide a basis for promoting the use of CFCs in similar applications.

Yellow Pigment Powders Based on Lead and Antimony: Particle Size and Colour Hue.

This paper reports the results of particle size analysis and colour measurements concerning yellow powders, synthesised in our laboratories according to ancient recipes aiming at producing pigments for paintings, ceramics, and glasses. These pigments are based on lead and antimony as chemical elements, that, combined in different proportions and fired at different temperatures, times, and with various additives, gave materials of yellow colours, changing in hues and particle size. Artificial yellow pigments, based on lead and antimony, have been widely studied, but no specific investigation on particle size distribution and its correlation to colour hue has been performed before. In order to evaluate the particle size distribution, segmentation of sample data has been performed using the MATLAB software environment. The extracted parameters were examined by principal component analysis (PCA) in order to detect differences and analogies between samples on the base of those parameters. Principal component analysis was also applied to colour data acquired by a reflectance spectrophotometer in the visible range according to the CIELAB colour space. Within the two examined groups, i.e., yellows containing NaCl and those containing K-tartrate, differences have been found between samples and also between different areas of the same powder indicating the inhomogeneity of the synthesised pigments. On the other hand, colour data showed homogeneity within each yellow sample and clear differences between the different powders. The comparison of results demonstrates the potentiality of the particle segmentation and analysis in the study of morphology and distribution of pigment powders produced artificially, allowing the characterisation of the lead and antimony-based pigments through micro-image analysis and colour measurements combined with a multivariate approach.

Investigation of Reinforced Particulate Flow and Distribution during Stirring Preparation of A356/SiCp with Experiment and Multi-phase Flow Simulation

Particulate-reinforced aluminum matrix composites produced by stirring casting method exhibit many advantages and are usually used in practical industries. The particulate flow and distribution during the stirring have significant effects on composite casting properties and performances. In this investigation, to study the effect of stirring parameters on particulate distribution, an experimental quenching apparatus was designed, and then A356/50μmSiCp prepared with different stirring speeds and positions were carried out. The particulate fractions at different locations of the prepared composites were quantitatively measured with micro-image analysis, and the charts of particulate distribution along axial directions were summarized and analyzed. Based on liquid-solid multiphase flow theory and multiple rotating reference frame models, a mathematical model of particulate-reinforced aluminum matrix composites stirring process established with consideration of relative flow between liquid and solid particle phases was applied to the experimental composite preparation. By comparing the simulation and experimental results, the effect of stirring condition on the composite slurry and particulate flow as well as the final particulate distribution were analyzed. The comparison shows that the simulated particle distribution exhibits well agreement with the experiment, indicating the validity and exactitude of the established model and method for actual composite stirring preparation. The study shows that low position of impeller would force more particles at the bottom region to flow with composite slurry, improving the particle distribution, and that high stirring speed can cause strong centrifugal force and radial flow of both composite slurry and particles, decreasing the particle uniformity in the composites.

Self-healing, re-adhering, and carbon-steel corrosion mitigating properties of fly ash-containing calcium aluminum phosphate cement composite at 300 °C hydrothermal temperature

This study assesses the ability of calcium aluminate phosphate (CAP)/fly ash F (FAF) blend composite to self-heal at early age; to re-adhere to the casing surfaces after debonding and to protect carbon steel (CS) against brine-caused corrosion before and after the re-adherence. The composite was damaged after autoclaving for 24 h at 300 °C and then exposed to the same conditions for 5 more days for the self-healing and re-adhering processes. The ability of the blend to self-heal and re-adhere to CS was evaluated 1) by measurements of the recovery of compressive and bond strengths and Young's modulus; 2) by performing the 3-dimensional micro-image analysis of sealed cracks; 3) by phase identification in composite matrix and in the cracks after the healing; 4) by measurements of CS corrosion impediment by the re-adhered composite after 300°C-5-day restoration period. After the healing, the two factors, sealing effect of cracks by reaction products and change in phase composition of cement matrix, essentially governed the recovery of the original mechanical strength. For the former, analcime phase derived from pozzolanic FAF autogenous healing aid played the major role in sealing the cracks, while the well-formed hydroxyapatite phase contributed to the latter factor. The lap-shear bond with the strength of 1.11 MPa at CS plate/composite adhesive/CS plate joint failed cohesively, showing higher bond strength than strength of the composite matrix. The rebonded composite-CS plates developed a 0.37 MPa bond strength after the 5-day restoration period. The results of electrochemical polarization corrosion tests revealed that the re-adhered composite covering CS plate significantly inhibited the brine-caused corrosion of CS, leading to 0.011 mm/year corrosion rate, corresponding to 50% reduction compared with that of before re-adhering. There were two factors governing such corrosion mitigation: enhanced adhesive contact of composite with CS and increased coverage by the re-adhering composite.

Novel applications of waste ceramics on the fabrication of foamed materials for exterior building walls insulation

In this paper, a novel fabrication method has been proposed by using waste ceramic and other polishing materials as main raw materials to prepare foam ceramic for the potential applications in thermal insulation of exterior building walls. In particular, the content of Al2O3 and SiO2 was almost 90% in this kind of materials. The polishing materials result from grinding polished tiles into powder and the ceramic foam was foamed slurry produced by self-configure foaming solution after mechanical stirring. Effects of content of foam and clay on the specimens’ properties such as compressive strength, apparent porosity, bulk density, water absorption and thermal conductivity were investigated. Based on results, when the content of clay was 10 wt%, the amount of foam was 10 wt%, apparent porosity of specimens sintered at 1000 °C was 50.6%, linear change was 7.2%, bulk density was 0.70 g/cm3, compressive strength was 8.0 MPa, and thermal conductivity was 0.137 W/(m·K) at 200 °C. Microstructures of specimens were also detected and compared, and the exceptional mean pore size was 39.7 μm which was measured by using “Micro-image Analysis and Process System” (MIAPS) software. Due to the difference in bulk density, the internal pore structure and performance of the sample are different. Comprehensive properties of specimens can be optimized by adjusting the amount of foam and clay. The proposed method for obtaining insulation foamed materials using ceramics' waste and other polishing materials was feasible, whilst saving resources and energy.

Localization of neonatal Fc receptor for IgG in aggregated lymphoid nodules area in abomasum of Bactrian camels (Camelus bactrianus) of different ages.

BackgroundThe neonatal Fc receptor (FcRn) plays a crucial role in transporting IgG and associated antigens across polarized epithelial barriers in mucosal immunity. However, it was not clear that FcRn expression in aggregated lymphoid nodules area (ALNA) in abomasum, a unique and important mucosal immune structure discovered only in Bactrian camels. In the present study, 27 Alashan Bactrian camels were divided into the following five age groups: fetus (10–13 months of gestation), young (1–2 years), pubertal (3–5 years), middle-aged (6–16 years) and old (17–20 years). The FcRn expressions were observed and analyzed in detail with histology, immunohistochemistry, micro-image analysis and statistical methods.ResultsThe results showed that the FcRn was expressed in mucosal epithelial cells of ALNA from the fetus to the old group, although the expression level rapidly declined in old group; moreover, after the ALNA maturated, the FcRn expression level in the non-follicle-associated epithelium (non-FAE) was significantly higher than that in FAE (P < 0.05). In addition, the FcRn was also expressed in the vessel endothelium, smooth muscle tissue, and macrophages and dendritic cells (DCs) of secondary lymphoid follicles (sLFs).ConclusionsIt was demonstrated that FcRn was mainly expressed in non-FAE, the effector sites, although which was expressed in FAE, the inductive sites for mucosal immunity. And it was also expressed in DCs and macrophages in sLFs of all ages of Bactrian camels. The results provided a powerful evidence that IgG (including HCAb) could participate in mucosal immune response and tolerance in ALNA of Bactrian camels through FcRn transmembrane transport.

Effects of pore structure on thermal conductivity and strength of alumina porous ceramics using carbon black as pore-forming agent

In the present work, carbon black (CB) works as a pore-forming agent in the preparation of alumina porous ceramics. The pore structures (i.e. mean pore size, pore size distribution and various pores size proportions) were characterized by means of Micro-image Analysis and Process System (MIAPS) software and mercury intrusion porosimetry. Then their correlation and thermal conductivity as well as strength were determined using grey relation theory. The results showed that the porosity and mean pore size increased against the amount of CB, whereas the thermal conductivity, cold crushing strength and cold modulus of rupture reduced. The <2μm pores were helpful for enhancing the strength and decreasing the thermal conductivity whereas the >14μm pores had the opposite effects.

Prevalence, intensity and complications of Microsporidium spores amongst HIV-positive hospital patients in Ilorin, Nigeria.

BackgroundMicrosporidiasis, which is of great concern for immunocompromised patients, is poorly studied in developing countries.ObjectivesA study was carried out amongst HIV-positive hospital patients and HIV-negative hospital controls in Ilorin, Nigeria, between January 2009 and July 2010 to determine the prevalence and intensity of Microsporidium spores and the complications associated with their presence.MethodStool samples from 750 HIV-positive patients and 375 HIV-negative patients were studied using the Chromotrope-2R staining technique. Determination of CD4+ count was performed on the Partec Cyflow SL-3 CD4/8 instrument. Intensity of spores was determined by counting the total number of the spores in a 10 µl stained smear of stool. Images were captured with Phenix Microimage Analysis Software and data obtained were analysed using the Statistical Package for the Social Sciences.ResultsThe prevalence of Microsporidium isolates amongst the HIV-positive hospital patients was significantly higher (42.4%) than amongst the HIV-negative controls (19.2%) (p < 0.05). The intensity of microsporidial spores amongst HIV-positive hospital patients was also significantly higher than amongst the controls (p < 0.05). However, the difference in the intensity of spores amongst HIV-positive patients who were on antiretroviral therapy (n = 411) and those who were not (n = 339) was not significant (p = 0.236). Microsporidiasis in HIV infection infection was common amongst patients with with low CD4+ counts, diarrhoea, body rashes and cough.ConclusionBoth the prevalence and intensity of Microsporidiasis are high amongst HIV-positive hospital patients; campaigns to promote awareness, prevention and control are required. Laboratory testing for microsporidia in HIV patients should be performed routinely so as to identify the organism for prompt medical attention.

Micro-mechanism of the interaction between sand and geogrid transverse ribs

ABSTRACT: To study the interaction between sand particles and geogrids, pullout tests were performed on one type of geogrid in Pingtan medium sand. The sand motion around the ribs was captured by high-resolution digital camera and CCD camera. The images were analysed with the aid of digital photography measurement and micro-image analysis. Microscopic particle motion and displacement fields around the transverse ribs were then obtained to verify the macro behaviour of the sand–rib interaction. It was found that the thickness of shear band increases with the normal stress applied, and the shear zone is asymmetrical to the soil–rib interface. A near wedge shape shear zone was observed by analysing the shear strain around the ribs, which indicated that a punching shear failure mechanism may be applicable to the tested geogrid in medium-dense sand. Comparison of various models for bearing capacity of geogrids shows that the size and shape of bearing members should be considered in the calculation of bearing resistance of geogrids.

Study on Direct Annealing Process of Hot-Rolled Plate

To study the transmutation of organization and texture on direct annealing process of hot-rolled plate. Different annealing experiments were done in the lab. The annealed samples are from steel grade of SPHC. To check the organization of the annealed samples by optical microscopy, to measure grain size by Micro-image Analysis &amp; process software. To measure the mechanical properties by the room temperature tensile test. To check AlN by TEM and EDX.To measure texture by texture measuring instrument, and the data was collected on a computer, using two-step calculation of ODF, measured with constant 45° section of graph. When annealing temperature of the samples reaches 875 °C or more, a relatively low strength , high n value, and high r value is received, but if the holding time is longer, grain coarsening occurs at the time,so the annealing temperature is not more than 925°C.When annealing temperature reaches 875 °C, AlN increased slightly, and the texture is not obvious.

Opposite effects of two different strains of equine herpesvirus 1 infection on cytoskeleton composition in equine dermal ED and African green monkey kidney Vero cell lines: application of scanning cytometry and confocal-microscopy-based image analysis in a quantitative study

Viruses can reorganize the cytoskeleton and restructure the host cell transport machinery. During infection viruses use different cellular cues and signals to enlist the cytoskeleton for their mission. However, each virus specifically affects the cytoskeleton structure. Thus, the aim of our study was to investigate the cytoskeletal changes in homologous equine dermal (ED) and heterologous Vero cell lines infected with either equine herpesvirus 1 (EHV-1) strain Rac-H or Jan-E. We found that Rac-H strain disrupted actin fibers and reduced F-actin level in ED cells, whereas the virus did not influence Vero cell cytoskeleton. Conversely, the Jan-E strain induced polymerization of both F-actin and MT in Vero cells, but not in ED cells. Confocal-microscopy analysis revealed that alpha-tubulin colocalized with viral antigen in ED cells infected with either Rac-H or Jan-E viruses. Alterations in F-actin and alpha-tubulin were evaluated by confocal microscopy, Microimage analysis and scanning cytometry. This unique combination allowed precise interpretation of confocal-based images showing the cellular events induced by EHV-1. We conclude that examination of viral-induced pathogenic effects in species specific cell lines is more symptomatic than in heterologous cell lines.

Study on relationship between genetic expression of BDNF and NRG-1 and myelinated nerve fiber density and cross-sectional area in thoracic sympathetic trunk of palmar hyperhidrosis

Objective To investigate the gene expression of brain-derived neurotrophic factor ( BD-NF) and neuregulin-1 (NRG-1) in thoracic sympathetic trunk and their relation to myelinated nerve fiber density and single myelinated nerve fibers cross-sectional area in palmar hyperhidrosis. Methods Fast red-fast green myelin sheath staining was used to show myelinated nerve fibers. Using the micro-image analysis system,30 cases of myelinated nerve fiber density and single myelinated nerve fibers cross-sectional area were observed in T3 thoracic sympathetic trunk of patients with palmar hyperhidrosis. BDNF and NRG-1 gene expression was also analyzed by RT-PCR. Eight cases of non-palmar hyperhidrosis patients served as controls. Results In 33 thoracic sympathetic trunk of patients with palmar hyperhidrosis, myelinated nerve fiber density and single myelinated nerve fibers cross-sectional area were significantly increased as compared with controls (t = 7. 023,P < 0.05 ; t = 7.462, P < 0.05 respectively). The expression of BDNF and NRG-1 in 33 thoracic sympathetic trunk of patients with palmar hyperhidrosis was 1. 176 00 ± 0.028 70,1. 216 10± 0.075 39 respectively, and that in control group was 1. 037 50 ± 0.053 79,1. 042 70 ± 0.043 57 respectively. The former was significantly higher than the latter ( t = 9.940,P < 0.05 ; t = 6. 195. P < 0.05 respectively). Conclusion BDNF and NRG-I gene over expression increased myelinated nerve fiber density and single myelinated nerve fibers cross-sectional area of thoracic sympathetic trunk in patients with palmar hyperhidro-sis. Thus transmission speed and ability of excitatory of thoracic sympathetic nerve were also increased, which may play a role in the pathogenesis of palmar hyperhidrosis. Key words: Palmar hyperhidrosis ; Thoracic sympathetic trunk ; NRG-1 ; BDNF

GRAFTING POLY(N-ISOPROPYL ACRYLAMIDE) FROM POLY(VINYLIDENE FLUORIDE) MIROFILTRATION, MEMBRANES VIA DIRECT SURFACE-INITIATED, ATOM TRANSFER RADICAL POLYMERIZATION, AND TEMPERATURE SENSITIVITY

Well-defined poly(N-isopropyl acrylamide) (PNIPAAm) brushes on commercial hydrophobic poly(vinylidene fluoride) (PVDF) microfiltration membrane surfaces were prepared, via direct atom transfer radical polymerization (ATRP) with the secondary fluorinated site of PVDF as initiator and water as solvent at 80°C. The effect of solvents on the ATRP was studied in detail. The water as reaction solvent was in favor of surface-initiated ATRP of N-isopropyl acrylamide (NIPAAm) from secondary fluoride of PVDF membranes. The chemical composition and structure of the modified PVDF membrane surfaces were determined by attenuated total reflectance (ATR) Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The surface and cross-section morphology of membranes were studied by scanning electron microscopy (SEM). The pore sizes of the pristine PVDF membrane and the PNIPAAm-grafted PVDF membranes were measured using micro-image analysis and process software. The introduction of the well-defined PNIPAAm on the PVDF membrane gave rise to hydrophilicity. Water contact angles of PVDF membranes reduced after the surface grafting of PNIPAAm. Water fluxes and protein solution permeation experiments revealed that the PNIPAAm-grafted PVDF membranes exhibited temperature-responsive permeability. The unique microstructure of PNIPAAm brushes facilitated hydrophilicity below the lower critical solution temperature.

Controlled grafting from poly(vinylidene fluoride) microfiltration membranes via reverse atom transfer radical polymerization and antifouling properties

A reverse atom transfer radical polymerization (RATRP) with benzoyl peroxide (BPO)/CuCl/2,2-bipyridine (Bpy) was applied onto grafting of poly(methyl methacrylate) (PMMA) and poly(poly(ethylene glycol) methyl ether methacrylate) (PPEGMA) from poly(vinylidene fluoride) (PVDF) microfiltration (MF) membrane surfaces, including the pore surfaces. The introduction of peroxide and hydroperoxide groups onto the PVDF membranes was achieved by ultraviolet (UV) irradiation in nitrogen, followed by air exposure. RATRP from UV pretreated hydrophobic PVDF membranes was then performed for attaching well-defined homopolymer. The chemical composition of the modified PVDF membrane surfaces was characterized by attenuated total reflectance (ATR) FT-IR spectroscopy and X-ray photoelectron spectroscopy (XPS). The surface and cross-section morphology of membranes were studied by scanning electron microscopy (SEM). The pore sizes of the pristine PVDF and the PMMA grafted PVDF membranes were measured using micro-image analysis and process software. With increase of graft concentration, the pore size of the modified membranes decreased and became uniform. Kinetic studies of homogeneous (in toluene solution) system revealed a linear increase in molecular weight with the reaction time and narrow molecular weight distribution, indicating that the chain growth from the membrane surface was a “controlled” or “living” grafting process. The introduction of the well-defined PMMA on the PVDF membrane gave rise to hydrophilicity. Protein adsorption and protein solution permeation experiments revealed that the UV pretreated hydrophobic PVDF membrane subjected to surface-initiated RATRP of methyl methacrylate (MMA) and poly(ethylene glycol) methyl ether methacrylate (PEGMA) exhibited good antifouling property.

Effect of mexican tea herb and pilular adina herb on concrescence of gastric mucosa in experimental gastric ulcer rats

To study the effect and mechanism of mexican tea herb and pilular adina herb (abbreviated to MP) on concrescence of gastric mucosa in experimental gastric ulcer rats by observing the changes of epidermal growth factor (EGF), nitrogen monoxidum (NO) and expression of epidermal growth factor receptor (EGFR). The rat ulcer model was established by 100% glacial acetic injection into the subserosa. The ulcer index (UI) was measured by sliding caliper. The levels of NO and EGF in tissue and serum were measured by the nitrate reductase method and enzyme-linked immunosorbent assay, respectively. The expression of EGFR in the mucosa around the ulcer was detected by the immunohistochemical assay and microimage analysis system. (1) Compared with the model group, UI of MP groups (10, 15 and 20 mg.kg(-1).d(-1)) and ranitidine group was lower (P<0.05 or P<0.01), the levels of NO and EGF in the tissue and serum were higher (P<0.05), the thickness of regenerated mucous membrane increased, and the width loss of lamina muscularis mucosa decreased (all P<0.05). (2) The expression of EGFR is weakly positive in gastric mucosa cells in the normal group, mainly in the cytoplasm and cytomembrane. In the model group, the expression of EGFR was mainly in epithelial cells in cervical part and basilar part of gastric gland around the ulcer margin, and the number of cells with EGFR weakly positive expression was more than that in the normal group. Compared with that in the normal and model groups, the number of cells with EGFR positive in MP groups and ranitidine group increased (all P<0.05), with weakly positive expression. MP can protect gastric mucosa, cure gastric ulcer, restrain the secretion of gastric acid, and boost multiplication, differentiation, migration and repair of the endothelial cell by promoting the secretion of NO and EGF, and increasing the expression of EGFR of gastric mucosa epithelial cells.

An experimental study on acute poisoning by fipronil in mice and its pharmaceutical therapy

To investigate the toxicity of fipronil in mice and the therapeutic effects of diazepam and phenobarbital sodium. Mice were administered by gastric tube with fipronil at six doses and their behavioral changes, pathological changes in their major viscera under light and electron microscopy and deaths were observed after acute poisoning. Distribution and quantity of nerve cells positive in glutamic acid (Glu) or gamma-aminobutyric acid (gamma-GABA) in the brain of mice were detected by immunohistochemical methods and micro-image analysis. The time of death time and survival rate were observed and compared between the varied groups of mice injected intraperitoneally with diazepam and phenobarbital sodium, respectively, 0.5 h after poisoning by fipronil at dose of 90 mg/kg. All the mice acutely poisoned by fipronil at varied doses showed some exciting symptoms in the central nervous system (CNS), including convulsion. Nuclear membrane space slightly expanded, neuroglia cells vacuolized and nerve fiber demyelinated under electron microscopy. The number and area of cells positive in Glu in the cerebral cortex of mice acutely poisoned by fipronil increased significantly, as compared to those in control mice. There was no significant difference in the number and area of cells positive in gamma-GABA in the hippocampal CA(1) region between poisoned and normal control groups. Survival rate of mice treated with diazepam or phenobarbital sodium was 58 percent. Mice with acute poisoning by fipronil appeared exciting symptoms in CNS, leading to damage in its nerve cells. Immunohistochemical techniques showed the damage could be related with the over-expression of glutamate transmitter in CNS. Early use of diazepam or phenobarbital sodium in treatment for acutely poisoned mice by fipronil could get better therapeutic efficacy.

Expression of Pax2 in Human Renal Tumor-Derived Endothelial Cells Sustains Apoptosis Resistance and Angiogenesis

The transcription factor Pax2 is known to play a key role during renal development and to act as an oncogene favoring renal tumor growth. We recently showed that endothelial cells derived from human renal carcinomas display abnormal characteristics of survival and angiogenic properties. In the present study we found that renal tumor-derived endothelial cells, but not normal endothelial cells, expressed Pax2 protein and mRNA. To down-regulate Pax2 expression, we transfected tumor-derived endothelial cells with an anti-sense PAX2 vector whereas we transfected normal human microvascular endothelial cells with a sense PAX2 vector to induce Pax2 expression. The inhibition of Pax2 expression in tumor-derived endothelial cells induced an increase in tumor suppressor PTEN expression and a decrease in Akt phosphorylation. In addition, decreased apoptosis resistance, adhesion, invasion, and in vitro and in vivo angiogenesis were observed. Conversely, Pax2 induction in normal endothelial cells conferred to these cells a proinvasive, proangiogenic phenotype similar to that of tumor-derived endothelial cells. These results indicate that Pax2 is involved in renal tumor angiogenesis and its expression may antagonize that of the PTEN tumor suppressor gene, affecting the Akt-survival pathway and promoting angiogenesis.

Disposition of 3H-selamectin and 3H-ivermectin in the brain of the cat flea Ctenocephalides felis felis using micro-image analysis

In addition to intrinsic potency and metabolic stability, the disposition of an antiparasitic drug within the target parasite plays a major role in determining drug activity. A novel technique that allows the disposition of radiolabelled drugs to be visualised within the body of the cat flea ( Ctenocephalides felis felis) is described. The concentrations of two macrocyclic lactones, 3H-selamectin and 3H-ivermectin, within the supra- and sub-oesophageal ganglia of the flea brain following in vitro feeding of fleas on different doses of drug solubilised in calf blood have been measured. Drug disposition was visualised in cryostat sections of fleas using a micro-image analysis (MIA). A relationship between the concentration of radioactivity in the ganglia and the dose of drug in the blood meal was obtained. The concentration of selamectin in the ganglia was significantly higher than ivermectin at all doses investigated. The enhanced concentration of selamectin, at a site rich in glutamate-gated chloride channels may, in part, explain the higher potency of selamectin against fleas compared to ivermectin.

Micro-image analysis in the diffusion-bonded zone of Fe3Al/Q235 carbon steel dissimilar materials

The chemical composition of the second phase precipitation in the vacuum diffusion-bonded zone of Fe3Al intermetallic compound and Q235 carbon steel was analysed by means of electron probe microanalyser (EPMA). The relative content of the second phase precipitation and grain size was evaluated through a micro-image analyser. The percentage of Fe and Al content in the diffusion zone was measured by EPMA. The results indicated that the relative content of the second phase precipitation rich in carbon and chromium at the Fe3Al/Q235 interface was much higher. With the transition from Fe3Al intermetallic compound to Q235 carbon steel across Fe3Al/Q235 interface, the grain diameter decreased from 250 μm, to 112 μm, Al atom content decreased from 27% to 15%, while Fe atom content increased from 76% to 96%.

Quantitative study on the mobility of Demodex folliculorum (Acari: Demodicidae) and inhibitive effects of metronidazole combined with bezoar

Abstract The mobility of human follicle mites may play an important role in the infestation and transmission of demodicidosis. In order to better understand the mobility of follicle mites and to test some miticides which may be responsible for the alteration of mobility of the mite, a Computer-Aided Microimage Processing and Analysis System (CAMPAS) for assaying the mobility of Demodex folliculorum was developed. The crawling velocity, as an index of mite mobility, showed a bimodal distribution with peaks from 0 to 40 µm/min and from 200 to 260 µm/min. Scarcely any mites with crawling velocity ranging from 80 to 160 µm/min were detected in these experiments. Adults of D. folliculorum showed two different mobility patterns: inactive and active. All mites with crawling velocity more than 200 µm/min were randomly exposed to (1) a mixture of 1% metronidazole plus 1% bezoar, (2) a mixture of 2% metronidazole plus 2% bezoar and (3) D-Hank's solution (as control). Based on the sequential data on the inhibitive e...