Microfabrication of position reference patterns onto glass microscope slides for high-accurate analysis of dynamic cellular events

Glass microscopes slides are widely used as in situ base-substrates carrying diverse micro-fabricated systems or elements. For such purposes, the micro-fabrication process consists in transferring a pre-defined design onto the substrate made of a glass microscope slide. This is known as patterning, which is a technique that can also be used in transferring specific designs that allows region of interest (ROI) recovery under the microscope. In those cases, two main challenges appear: 1) Disturbances in light transmission should remain minimum to keep the high quality of observation of the object of interest under the microscope. 2) The pattern-size should then be small enough but, however, larger than the diffraction limit to be observable satisfactorily for positioning purposes. In this article, we present the procedures involved in the microfabrication of Pseudo-Periodic Patterns (PPP) encrypting the absolute position of an extended area. Those patterns are embedded in Pétri dishes in order to allow the highaccurate retrieval of absolute position and orientation. The presented microfabrication is based in a technique known as lift-off, which after parameter adjustment, allows the obtaining of PPP fulfilling the two previously mentioned requirements. The results report on PPP realized on glass microscope slides and composed by 2µm side dots made of aluminum with a thickness of 30nm.

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The disposition of benzo(a)pyrene in the periphyton communities of two South Carolina streams: uptake and biotransformation

Canadian Journal of Botany ◽

10.1139/b82-255 ◽

1982 ◽

Vol 60 (10) ◽

pp. 2084-2091 ◽

Cited By ~ 9

Author(s):

Mary G. Bruno ◽

Timothy E. Fannin ◽

Gordon J. Leversee

Keyword(s):

South Carolina ◽

Slide Surface ◽

Uptake Rates ◽

Area Basis ◽

Autoradiographic Analysis ◽

Colonization Time ◽

Microscope Slides ◽

Surface Area Basis ◽

Glass Microscope ◽

Sheath Material

The effect of periphyton community composition and colonization time on the uptake and biotransformation of benzo(a)pyrene (BaP) was determined in laboratory studies. Naturally colonized glass microscope slides were collected after 3 and 6 weeks from Castor Creek, which has a predominantly desmid flora, and after 3 and 5 weeks from diatom-dominated Upper Three Runs Creek. When expressed on a slide surface-area basis, the Castor Creek periphyton showed significantly greater BaP uptake rates at both colonization periods. Within streams, uptake rates increased significantly with colonization time. Autoradiographic analysis suggests that BaP was accumulated by surface sorption, especially to gelatinous sheath material. Active biotransformation as measured by the percentage extractable non-BaP 14C was not detected in either community.

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Photolytic degradation of 2,4-D onZea maysleaves

Weed Science ◽

10.1017/s004317450009175x ◽

1999 ◽

Vol 47 (3) ◽

pp. 262-269 ◽

Cited By ~ 3

Author(s):

Ramarao Venkatesh ◽

S. Kent Harrison

Keyword(s):

Zea Mays ◽

Time Course ◽

Uv Light ◽

Light Regime ◽

Growth Chamber ◽

Polychromatic Light ◽

Photolytic Degradation ◽

Microscope Slides ◽

Glass Microscope

Growth chamber experiments were conducted to determine the effects of UV light and riboflavin on photolysis of 2,4-D applied toZea maysleaves. Droplets of 100 mg L−114C-2,4-D were applied toZ. maysleaves with and without 10 mg L−13H-riboflavin and exposed to either UV-enhanced or UV-attenuated polychromatic light in a time-course assay. Photolysis of nonabsorbed14C-2,4-D residues onZ. maysleaves was sensitized by riboflavin regardless of UV light regime, but a larger percentage of nonabsorbed herbicide was degraded under UV-enhanced light compared to UV-attenuated light. Riboflavin was almost completely photolyzed during the first 10 h of exposure; yet, photolysis of14C-2,4-D surface residues in treatments containing riboflavin increased from 59% at 10 h of exposure to 87% at 42 h of exposure. In corresponding treatments without riboflavin, photolysis of14C-2,4-D surface residues was 37% at 10 h of exposure and 84% at 42 h of exposure. In contrast, only 7% of the14C-2,4-D deposited on glass microscope slides was degraded after 42 h of exposure in the absence of riboflavin, whereas 59% was degraded in the presence of riboflavin. Photolysis of 2,4-D onZ. maysleaves in treatments without riboflavin suggests that certain epicuticular component(s) ofZ. maysacted as photosensitizers or catalytic agents that promoted photolysis of nonabsorbed 2,4-D residues.

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Botryosphaeriaceae Species Spore-Trapping Studies in California Vineyards

Plant Disease ◽

10.1094/pdis-94-6-0717 ◽

2010 ◽

Vol 94 (6) ◽

pp. 717-724 ◽

Cited By ~ 56

Author(s):

J. R. Úrbez-Torres ◽

M. Battany ◽

L. J. Bettiga ◽

C. Gispert ◽

G. McGourty ◽

...

Keyword(s):

Strong Relationship ◽

Early Spring ◽

Seasonal Abundance ◽

Petroleum Jelly ◽

Riverside County ◽

Spore Release ◽

Spore Trapping ◽

Rain Events ◽

Microscope Slides ◽

Glass Microscope

The seasonal abundance of Botryosphaeriaceae spp. spores was studied in California vineyards by using glass microscope slides covered with petroleum jelly placed on grapevine cordons and Burkard volumetric spore traps at seven and two different locations, respectively. Correlation analysis was used to determine which meteorological variables (precipitation, relative humidity, temperature, and wind speed) influenced Botryosphaeriaceae spp. spore release. Among all variables, regression analysis resulted in a strong relationship between spore release and precipitation. Additionally, a positive relationship between irrigation and spore release was also observed in the Riverside County vineyard. During the study period, spore discharge of Botryosphaeriaceae spp. occurred from the first fall rain through the last spring rains, coinciding with September to April. However, based on the results obtained from the spore traps, most spores (over 60%) were trapped following rain events during the winter months of December, January, and February, which coincides with the grapevine pruning season. Botryosphaeriaceae spp. spore release was much lower in fall and early spring (22%) and very few or no spores were trapped in late spring and summer (3%). This work suggests that a delay of pruning time in California may be warranted to reduce grapevine infection because the current timing coincides with the greatest period of spore discharge.

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Lift -Off Process to get Free-Standing High Quality Single Crystal Diamond Films and Suspended Single Crystal Diamond Devices

MRS Proceedings ◽

10.1557/proc-0956-j17-01 ◽

2006 ◽

Vol 956 ◽

Cited By ~ 2

Author(s):

Jie Yang ◽

C. F. Wang ◽

E. L. Hu ◽

James E. Butler

Keyword(s):

Ion Implantation ◽

Single Crystal ◽

Light Transmission ◽

Electrochemical Etching ◽

Etching Process ◽

Critical Parameters ◽

Transmission Microscopy ◽

Single Crystal Diamond ◽

Cvd Growth ◽

Lift Off

ABSTRACTFreestanding and suspended single crystal diamond devices, micro disks and beam structures, have been fabricated on single crystal diamond substrates using a lift-off process employing ion implantation followed by electrochemical etching. The ion implantation created subsurface damage in the diamond while the top surface was sufficiently undamaged that a subsequent homo-epitaxial diamond layer could be grown by chemical vapor deposition (CVD). After the CVD growth and patterning by lithography and reactive ion etching, the underlying damage layer was etched/removed by an electrochemical etch. Different implant ions and energies were simulated and tested to optimize the process. The electrochemical etching process was monitored by an optical video technique. The electrochemical etching process used both ac and dc applied electrical potentials. Photoluminescence (PL), Raman spectra, and polarized light transmission microscopy have been used to characterize the implanted substrate and lift-off films. AFM has been used to monitor the surface changes after mechanical polishing, ion implantation, CVD growth and the lift-off process. This research has revealed that the parameters of ion implantation (implant species, dose and energy) dramatically affect the lift-off process. The etching mechanism and critical parameters are discussed in this work. PL spectroscopy indicated differences between the uppermost layers of the homo-epitaxial film and the lift-off interface. Three principal classes of defects have been observed: growth defects inherent in the diamond substrates (type Ib, HPHT), defects induced by the polishing process and associated stress, and point defects.

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A mammary gland whole mount technique that preserves cell fine structure for electron miscroscopy.

Journal of Histochemistry & Cytochemistry ◽

10.1177/27.9.479569 ◽

1979 ◽

Vol 27 (9) ◽

pp. 1271-1274 ◽

Cited By ~ 7

Author(s):

J M Strum

Keyword(s):

Electron Microscopy ◽

Methylene Blue ◽

Fine Structure ◽

Mammary Gland ◽

Trypan Blue ◽

Negative Image ◽

Whole Mount ◽

Microscope Slides ◽

Glass Microscope ◽

Unusual Finding

A mammary gland whole mount technique has been developed that preserves cell fine structure and makes it possible to also examine the preparations by electron microscopy. The glands are placed on glass microscope slides, fixed in a paraformaldehyde-glutaraldehyde mixture, defatted in acetone, stained with 0.5% methylene blue (or trypan blue) in saline, and dehydrated in ethanol. They are evaluated and photographed in 100% ethanol. Then specific areas (i.e. containing small growths, tumors, or other lesions) are selected, excised and prepared for electroscopy. The ultrastructural preservation is good, organelles are evident and there is no observable dye precipitate. The only unusual finding is that cell membranes display a "negative" image.

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Dynamics of Two-Phase Flow through a Minichannel: Fourier and Multiscale Entropy Analyses

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.791.217 ◽

2015 ◽

Vol 791 ◽

pp. 217-223 ◽

Cited By ~ 2

Author(s):

Grzegorz Górski ◽

Grzegorz Litak ◽

Romuald Mosdorf ◽

Andrzej Rysak

Keyword(s):

Light Transmission ◽

Digital Camera ◽

Multiscale Entropy ◽

Air Bubbles ◽

Periodic Patterns ◽

Two Phase ◽

Temporal Behaviour ◽

Air Bubble ◽

Flow Through ◽

Spatio Temporal

By changing a air flow rate of the two-phase (air-water) flow through a minichannel weidentified aggregation and partitioning of air bubbles and slugs of different sizes and air bubble arrangement into periodic patterns. The identification of these spatio-temporal behaviour was doneby digital camera. Simultaneously, we provide the detailed studies of these phenomena by using thecorresponding sequences of light transmission time series recorded by a laser-phototransistor sensor.To distinguish the instabilities in air slags and their breakups and aggregations we used the Fourierand multiscale entropy analysis.

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Development of a rapid diagnostic test for the detection of antibodies or antigens to Coronavirus (COVID-19)

Fields journal of Huddersfield student research ◽

10.5920/fields.978 ◽

2021 ◽

Author(s):

James Elliff

Keyword(s):

Low Income ◽

Rapid Detection ◽

Spike Protein ◽

Low Income Countries ◽

Health Crisis ◽

Significant Difference ◽

Specific Antigens ◽

Microscope Slides ◽

Glass Microscope ◽

Control Samples

Theglobal health crisis caused by COVID-19 has overwhelmed both healthcaresettings and economies globally. Whilst mass population testing has improveddrastically, recent reviews of existing methods have highlighted variousshortcomings with these methods. Theaim of this project was to investigate whether the LAA could be modified andutilised as rapid detection test which either matched or exceeded the existingsensitivity and specificity values.   TheLAA investigated whether the COVID-19 spike protein could be detected insamples. COVID-19 specific IgM and IgG were used in conjunction with a seriesof non-specific antigens. Control or AG containing samples weremixed with AB-microsphere complexes on glass microscope slides. Manualvisualisation identified various levels of agglutination. Light microscopy andspectrophotometry at 405nm determined that the LAA could detect at least 2.3ngof spike protein.  Theparticle counting tool of ImageJ was utilised to obtain a dataset which wassubjected to statistical analysis which indicated that there was a significantdifference between control samples and live tests, P = 0.000102 for the spikeprotein assay and P = 0.254 for the non-specific assay respectively. Theresults obtained fell in line with a similar study conducted by Buffin et al in2018. Theanalytical methods used in this project twinned with data obtained in previousstudies supports the significant difference between control values and livetest values. The LAA is easier, quicker to use (results in ≤ 30 minutes) andcheaper, with potentially better sensitivity to existing methods. This couldbenefit high and low-income countries alike upon further research andoptimisation. 

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Mechanical Robustness of Solder Connections to Thick Film Gold

International Symposium on Microelectronics ◽

10.4071/isom-2011-tp4-paper2 ◽

2011 ◽

Vol 2011 (1) ◽

pp. 000327-000336

Author(s):

Thomas F. Marinis ◽

Joseph W. Soucy

Keyword(s):

Thick Film ◽

High Reliability ◽

Accelerated Aging ◽

Element Analysis ◽

Bga Packages ◽

Fine Pitch ◽

Solder Balls ◽

Lift Off ◽

Extended Area ◽

Gold Metallization

Thick film gold metallization is required for many high reliability circuits, especially those subjected to operation in high temperature or high humidity environments. Traditionally, wire bonded bare die are used on these circuits, but there is a trend to replace them with BGA packaged devices. State-of-the-art, chip scale packages increase circuit volume by less than 20 percent, while their use greatly simplifies testing and repair, as compared to wire bonded die. The use of small, high density I/O pad arrays for attachment of BGA packages, necessitates very careful control of the solder reflow process to avoid excessive leaching of the gold into the solder. Also, unlike passive chip components and leaded devices, the solder filet associated with a solder ball attachment does not distribute mechanical loads over an extended area. Consequently, the stresses imposed on fine pitch, BGA pads are much higher than those imposed by other components. During aging, the gold metallization is converted to gold-tin intermetallic as inter-diffusion proceeds. This further reduces the mechanical integrity of the solder connection. This manifests itself in the observation that when BGA solder balls are subjected to accelerated aging followed by shear testing, the entire solder pad lifts off of the substrate, rather than failing in the solder joint. What we have done is construct a diffusion based model to estimate the conversion of a thick film gold metallization pad to intermetallic and coupled this result with a finite element analysis to examine the effect of pad size and solder composition on the propensity of a pad to lift off the substrate, when subjected to mechanical or thermal induced loading. We are designing experiments to compare the predictions of our model to experimental results obtained from shearing solder balls, of different compositions and sizes, attached to substrates metalized with several different solderable, thick film gold materials.

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Optimization of the binding of dissociated exfoliated cervico-vaginal cells to glass microscope slides.

Journal of Histochemistry & Cytochemistry ◽

10.1177/25.7.894002 ◽

1977 ◽

Vol 25 (7) ◽

pp. 538-543 ◽

Cited By ~ 12

Author(s):

R C Leif ◽

D Ingram ◽

C Clay ◽

D Bobbitt ◽

R Gaddis ◽

...

Keyword(s):

The Other ◽

Centrifugal Field ◽

Bonding Agents ◽

Cell Dissociation ◽

Silicone Coating ◽

Glass Slides ◽

Acceleration And Deceleration ◽

A Cell ◽

Microscope Slides ◽

Glass Microscope

In order to monitor the development of a cell dissociation technique, it was essential to utilize the Centrifugal Cytology rotor to produce glutaraldehyde-fixed even cellular dispersions. The Cytology rotor has been improved to insure rapid alignment with the centrifugal field during both acceleration and deceleration, and the fixative is now delivered to the surface of the slide. The dissociation of the cells results in a loss of their adhesion to glass slides. Three bonding agents were tested: (a) Poly-L-Lysine; (b) Mayer's albumin fixative; (c) positively charging the slides with a silicone coating. The results with 65% albumin-coated slides were clearly superior to the other two. The addition of a postfixation step of 95% ethanol/4% polyethylene glycol did not significantly affect the recovery of the cells, but did eliminate some unevenness in the Centrifugal Cytology preparations, flattened the cells and expedited the procedure.

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Automatic Detection of Airway Invasion from Videofluoroscopy via Deep Learning Technology

Applied Sciences ◽

10.3390/app10186179 ◽

2020 ◽

Vol 10 (18) ◽

pp. 6179

Author(s):

Seong Jae Lee ◽

Joo Young Ko ◽

Hyun Il Kim ◽

Sang-Il Choi

Keyword(s):

Deep Learning ◽

Present Model ◽

Spinal Column ◽

Region Of Interest ◽

Learning Technology ◽

Accurate Analysis ◽

Human Errors ◽

Airway Invasion ◽

Human Effort ◽

Deep Learning Model

In dysphagia, food materials frequently invade the laryngeal airway, potentially resulting in serious consequences, such as asphyxia or pneumonia. The VFSS (videofluoroscopic swallowing study) procedure can be used to visualize the occurrence of airway invasion, but its reliability is limited by human errors and fatigue. Deep learning technology may improve the efficiency and reliability of VFSS analysis by reducing the human effort required. A deep learning model has been developed that can detect airway invasion from VFSS images in a fully automated manner. The model consists of three phases: (1) image normalization, (2) dynamic ROI (region of interest) determination, and (3) airway invasion detection. Noise induced by movement and learning from unintended areas is minimized by defining a “dynamic” ROI with respect to the center of the cervical spinal column as segmented using U-Net. An Xception module, trained on a dataset consisting of 267,748 image frames obtained from 319 VFSS video files, is used for the detection of airway invasion. The present model shows an overall accuracy of 97.2% in classifying image frames and 93.2% in classifying video files. It is anticipated that the present model will enable more accurate analysis of VFSS data.

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