Evaluation of Three Different Cleaners Recommended for Ultrafiltration Systems by Direct Observations of Commercial-Scale Spiral-Wound Ultrafiltration Membranes1

1988 ◽  
Vol 51 (2) ◽  
pp. 89-104 ◽  
Author(s):  
K. E. SMITH ◽  
R. L. BRADLEY
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Visual Inspection ◽  
Membrane Materials ◽  
Direct Observations ◽  
Commercial Scale ◽  
Sweet Whey ◽  
Scanning Electron ◽  
Polysulfone Membranes ◽  
Spiral Wound

Efficacy of cleaners designed for use with ultrafiltration systems was determined by microbiological evaluation and through visual inspection using scanning electron microscopy. The ultrafiltration system containing two commercial-scale, polysulfone membranes was soiled with sweet whey (40°C) then rinsed with water and membranes were removed. One half of each membrane was soaked for 2 h at 38°C in one of the following solutions: control (no soaking), acid cleaner (pH 2.5), enzyme-based cleaner (pH 11.5) and chlorinated alkaline cleaner (pH 11.5). The membranes were repositioned in the ultrafiltration unit, rinsed with water, then removed and unwound for analysis. Sections of membrane, retentate spacer and permeate mesh were aseptically removed for enumeration of microorganisms remaining and for examination by scanning electron microscopy. Membranes cleaned with chlorinated alkaline cleaner averaged 2 × 103 CFU/50 cm2, enzyme-based cleaner 6 × 106/CFU, acid anionic cleaner 1 × 107 CFU and the control 5 × 107CFU. Scanning electron microscopy found soil and microorganisms present on all membrane materials exposed to all three cleaners.

scholarly journals Pilot investigation into osteotome hard surface coating and cutting-edge degradation

2020 ◽  
Author(s):  
David White ◽  
Jim Bartley ◽  
Christopher Whittington ◽  
Lorenzo M. G. Garcia ◽  
Kaushik Chand ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Titanium Nitride ◽  
Visual Inspection ◽  
Visual Analysis ◽  
Electroless Nickel ◽  
Cutting Edge ◽  
Edge Sharpness ◽  
Blade Edge ◽  
Scanning Electron

Abstract BackgroundOsteotomes are bone cutting tools commonly reused in orthopedic surgical procedures. Despite undergoing rigorous cleaning, visual inspection and sterilization procedures between every use, the condition of the cutting blade edge is commonly not qualitatively assessed. Subjective feedback from surgeons suggests a large variation in osteotome cutting edge sharpness is found during use. This study seeks to investigate the retention of osteotome cutting-edge sharpness by comparing the wear resistance of as-supplied, electroless nickel, and titanium nitride coated osteotomes following a series of bone cutting tests.MethodsChanges in edge sharpness were assessed using visual inspection, depth penetration testing that quantified change in the blade sharpness index and scanning electron microscopy visual analysis. Visual inspection of each osteotome blade edge was then compared to qualitative blade sharpness index measurement.ResultsAfter use, no cutting-edge damage or change in blade sharpness was detected by visual examination of all three osteotomes however the as-supplied osteotome demonstrated 50% loss of blade sharpness index compared to 30% and 15% reduction for the electroless nickel and titanium nitride coated osteotomes respectively. This finding was supported by scanning electron microscopy evaluation that found greater mechanical damage had occurred along the cutting-edge of the as-supplied osteotome compared to the two coated with wear resistant materials.ConclusionsThe rapid loss of blade sharpness found in the as-supplied osteotome supports the degradation in cutting performance frequently reported by surgeons. The findings from this study demonstrates blade sharpness index better detects cutting edge wear compared to visual inspection. Results from this pilot study also suggest the coating of osteotomes in hard-wearing biocompatible materials assists in retaining cutting edge sharpness over multiple uses. Further study using a larger sample size is required to validate these findings.

Character analysis of adaptations for tarsal pollen collection in the Bombyliidae (Insecta: Diptera): the benefits of putting your foot in your mouth

Zootaxa ◽  
2003 ◽  
Vol 157 (1) ◽  
pp. 1 ◽  
Author(s):  
JOHN L. NEFF ◽  
BERYL B. SIMPSON ◽  
NEAL L. EVENHUIS ◽  
GREGG DIERINGER
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Gut Contents ◽  
Character Analysis ◽  
Pollen Collection ◽  
Direct Observations ◽  
Pollen Feeding ◽  
The Family ◽  
Scanning Electron

Using direct observations and analyses of gut contents, we document that pollen feeding is widespread among female bombyliid flies. Pollen feeding is typically indirect with the initial pollen acquisition accomplished by foretarsal stroking of the anthers. Observations of the foretarsi using light and scanning electron microscopy showed that the foretarsi bear modified setae that play a role in pollen collection. Across the family, we found considerable variation in the morphology and distribution of the foretarsal setae that appear to be more related to phylogeny than pollen host. The major patterns of foretarsal setal specialization are illustrated and discussed.

scholarly journals A modified ‘NanoSuit®’ preserves wet samples in high vacuum: direct observations on cells and tissues in field-emission scanning electron microscopy

2017 ◽  
Vol 4 (3) ◽  
pp. 160887 ◽  
Author(s):  
Yasuharu Takaku ◽  
Hiroshi Suzuki ◽  
Hideya Kawasaki ◽  
Isao Ohta ◽  
Daisuke Ishii ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Field Emission ◽  
Structural Changes ◽  
Cultured Cells ◽  
High Vacuum ◽  
Insect Larvae ◽  
Direct Observations ◽  
High Vacuum Environment ◽  
Scanning Electron

Although field-emission scanning electron microscopy (FE-SEM) has proven very useful in biomedical research, the high vacuum required (10 −3 to 10 −7  Pa) precludes direct observations of living cells and tissues at high resolution and often produces unwanted structural changes. We have previously described a method that allows the investigator to keep a variety of insect larvae alive in the high vacuum environment of the electron microscope by encasing the organisms in a thin, vacuum-proof suit, the ‘NanoSuit®'. However, it was impossible to protect wet tissues freshly excised from intact organisms or cultured cells. Here we describe an improved ‘NanoSuit' technique to overcome this limitation. We protected the specimens with a surface shield enhancer (SSE) solution that consists of glycerine and electrolytes and found that the fine structure of the SSE-treated specimens is superior to that of conventionally prepared specimens. The SSE-based NanoSuit affords a much stronger barrier to gas and/or liquid loss than the previous NanoSuit did and, since it allows more detailed images, it could significantly help to elucidate the ‘real' organization of cells and their functions.

scholarly journals Drawing-Induced Evolution of Inclusions in Cold-Drawn Pearlitic Steel

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1272
Author(s):  
Jesús Toribio ◽  
Francisco-Javier Ayaso ◽  
Rocío Rodríguez
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Image Analysis ◽  
Visual Inspection ◽  
Cold Drawing ◽  
Pearlitic Steel ◽  
Drawing Process ◽  
Analysis Program ◽  
Hot Rolled ◽  
Scanning Electron

This article focuses on the analysis of the evolution of inclusions present in eutectoid pearlitic steel subjected to a real cold drawing process. To this end, wires belonging to different stages of the manufacture chain were studied, starting from an initial hot rolled bar (not cold drawn at all). In addition to the information obtained through visual inspection, a quantitative analysis of the microdefects generated by these inclusions was carried out. The analysis was performed using materialographic techniques, scanning electron microscopy (SEM) and the image analysis program (AnaliSYS 3.1®).

scholarly journals Potential Use of Carrageenans against the Limestone Proliferation of the Cyanobacterium Parakomarekiella sesnandensis

2021 ◽  
Vol 11 (22) ◽  
pp. 10589
Author(s):  
Fabiana Soares ◽  
João Trovão ◽  
Francisco Gil ◽  
Lídia Catarino ◽  
Igor Tiago ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cultural Heritage ◽  
Visual Inspection ◽  
Antimicrobial Properties ◽  
Alternative Methods ◽  
Red Seaweed ◽  
Laboratory Conditions ◽  
Potential Use ◽  
Scanning Electron

Stone biodeterioration by cyanobacteria is a common issue in the field of cultural heritage. As they are considered the first stone colonizers, the need to control their growth has increased. In this study, we evaluated the effectiveness of kappa/iota carrageenans from the red seaweed Chondracanthus teedei var. lusitanicus against the limestone proliferation of the cyanobacterium Parakomarekiella sesnandensis, under laboratory conditions. For this purpose, 200 μL of kappa/iota carrageenans (0.01 g mL−1) were applied into the surface of the limestone replicas prior to their inoculation with P. sesnandensis. Results were evaluated after 4 months of incubation through visual inspection, stereomicroscopy, scanning electron microscopy and colorimetric analyses. The gathered data demonstrated that these types of carrageenans have the potential to reduce the colonization of P. sesnandensis. With one sole application, the aesthetical alterations caused by the proliferation of P. sesnandensis were drastically reduced. This study highlights the need to explore marine-based products, particularly those derived from seaweeds with antimicrobial properties, as alternative methods for biocleaning cultural heritage assets.

Characterization of Biodegradation of Fiber Cement Shingles by Scytonema Sp. Using Optical and Scanning Electron Microscopy

2001 ◽  
Vol 7 (S2) ◽  
pp. 472-473
Author(s):  
Barbara A. Reine ◽  
Colin Murphy
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Optical Microscopy ◽  
Visual Inspection ◽  
The Arctic ◽  
New Material ◽  
The Antarctic ◽  
Scanning Electron

Fiber cement roofing shingles from condominiums in Hawaii were examined for deterioration using optical and scanning electron microscopy. The product has a 50 year warranty and had been in service since 1994. Shingle samples were taken in August and September, 2000 after a growing volume of reports of roofing deterioration were received by the condominium association. Close-up visual inspection confirmed that the roof areas showing deterioration were covered with a black growth. Roofing samples from areas exhibiting deterioration, areas with no deterioration, and new material were compared by microscopy.Examination of the black growth by optical microscopy revealed it to be primarily the Cyanobacterium, Scytonema sp.This is a filamentous organism found from the Arctic to the Antarctic, and is common to Oahu and Maui.’ Other organisms observed to be present are Chroococus sp., Gloeocapsa sp., Aphanocapsa sp., Oscillatoria sp.,a very few Trebouxia sp.and lichens.

Scanning electron microscopy of the digestive tract of larval Simulium ornatum Meigen (Complex) (Diptera: Simuliidae) and its associated microbial flora

1995 ◽  
Vol 73 (9) ◽  
pp. 1640-1646 ◽  
Author(s):  
Mark R. Taylor ◽  
Stephen T. Moss ◽  
Mike Ladle
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Digestive Tract ◽  
Freeze Fracture ◽  
Microbial Flora ◽  
Peritrophic Membrane ◽  
Filamentous Bacteria ◽  
Direct Observations ◽  
Dissection Technique ◽  
Scanning Electron

The structure and microbial flora of the digestive tract of larval Simulium ornatum were investigated using scanning electron microscopy. Direct observations of the microbial communities associated with the endoperitrophic surface of the peritrophic membrane and the endocuticular surface of the hindgut are presented. The endoperitrophic surface was frequently devoid of bacteria, although the fungus Harpella melusinae (Harpellales, Trichomycetes) was commonly attached. Rarely, spirochaetes and coccoid bacteria were attached to the endoperitrophic surface. In contrast, the endocuticular surface was regularly colonized by a diverse microflora composed of rod-shaped, coccoid, spiral, and filamentous bacteria and two species of Harpellales (Trichomycetes). A freeze-fracture technique is compared with a dissection technique for exposing the endoperitrophic and endocuticular surfaces of the digestive tract.

Pathogenesis of Human Hair Defects

1974 ◽  
Vol 32 ◽  
pp. 12-13
Author(s):  
P.S. Porter ◽  
T. Aoyagi ◽  
R. Matta
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Human Hair ◽  
Standard Techniques ◽  
Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

1977 ◽  
Vol 35 ◽  
pp. 638-639
Author(s):  
P.J. Dailey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salivary Glands ◽  
Secretory Vesicles ◽  
The Past ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Gromphadorhina Portentosa ◽  
Scanning Electron ◽  
Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

Sign in / Sign up

Export Citation Format

Share Document