Learn how to use Gram staining to differentiate beneficial bacteria from dangerous bacteria in food samples. Working in the virtual lab of a dairy processing plant, you analyze yogurt samples and follow step-by-step lab procedures to test for Salmonella and E. coli. Sterilize your inoculation loop, and prepare your slide, then view the sample under a microscope and observe the differences in appearance between beneficial bacteria and harmful bacteria. The interactive initially guides the user through each step of the lab process; then users prepare Gram stain slides on their own to find out for certain whether this batch of yogurt is safe.
Lab technicians use microscopes for many tasks, including checking what kinds of microbes are present in a sample.Using a microscope is one of the basic skills of laboratory work. Learn how to choose the correct lens, adjust lighting and magnification, and prepare a slide for viewing. Using Gram staining and a microscope, you can differentiate beneficial bacteria from dangerous bacteria in food samples. In this module, enter the virtual lab of a dairy processing plant to analyze yoghurt samples and test for Salmonella and E. coli. The interactive guides the user through theory and practice of using the microscope, so that they will have familiarity with the equipment and procedures when encountered in a real lab.
This high-resolution scanning electron microscope image shows an unusual tube-like structural form that is less than 1/100th the width of a human hair in size found in meteorite ALH84001, a meteorite believed to be of Martian origin. Although this structure is not part of the research published in the Aug. 16 issue of the journal Science, it is located in a similar carbonate glob in the meteorite. This structure will be the subject of future investigations that could confirm whether or not it is fossil evidence of primitive life on Mars 3.6 billion years ago.
These barriers to quantitative imaging raise important questions about mobile phone microscopes: are mobile phones in their current form suitable for diagnostic applications, and do lower-cost optical components used in mobile phone microscopes compared to scientific microscopes ultimately limit their capabilities? Initial efforts to use mobile phone cameras for both medical and scientific applications highlighted these concerns, with some studies concluding that mobile phones are inadequate for pathology  or limited in their image quality . However, other work has shown that a full-size microscope equipped with a phone camera can qualitatively capture relevant features of malaria and TB . These opposing conclusions, along with recent advancements in the hardware and software of mobile phone cameras, point to the need for a detailed analysis of quantitative imaging with a mobile phone-based microscope.
A The resolution that can be captured with a mobile phone microscope approaches that of a scientific camera coupled to the same optics across a range of numerical apertures. Inset shows the measured intensity profile across bars of non-transmitting chrome spaced at 512 line pairs per millimeter and taken with a 10×/0.25 NA objective, as well as the ideal target profile. The Michelson contrast calculated for this example group is 41%, indicating that features with this spacing are resolved. B Wright stained blood smear with an inset of a granulocyte and red blood cells taken with a 10×/0.25 NA objective and iPhone 4. C Image of the same sample and region of interest taken with a 40×/0.65 NA objective and iPhone 4 showing improved resolution.
A The spatial resolution of mobile phone microscopy with iPhone and Android phones is plotted as a function of the effective pixel size for images taken with a 10×/0.25 NA objective. The theoretical constraints on resolution imposed by pixel spacing on the Bayer color sensor array are plotted along with the empirically determined resolution limit of the underlying microscope optics. B The spatial resolution of mobile phone microscopy with the same iPhone and Android phones is plotted as a function of megapixel count. C Spatial resolution of the iPhone family of phones is plotted over time, together with the dates of significant camera advancements.
In this study, we systematically address the issue of quantitative microscopy with a mobile phone by constructing a mobile phone microscope and evaluating the quality of images taken with a range of different mobile phones. We first characterized the resolution of the optics of the CellScope mobile phone microscope, examining the extent to which phones released in different years with different pixel counts are capable of capturing the information collected by the microscope optics. We also evaluated other optical characteristics of the system including uniformity and distortion across the field of view, as well as the linearity of the phone response to intensity. We then demonstrated the difficulty of obtaining a reproducible, spectrally accurate response across multiple samples for quantitative purposes when using the default camera functionality of the phone. Finally, we outlined a protocol to minimize variation across images to enable a workflow for capturing consistent data for quantitative applications. With the standardization and recording of assay parameters, image data can be structured according to the DICOM standard, enabling the integration of specimen data into existing hospital workflows for picture archival and pathology. For long-term or scaled up use of these systems, it will be important to note changes to manufacturers or updates to image processing software which may require corresponding re-standardization.
Illinois State University received a $403,900 grant from the National Science Foundation for the acquisition of a state-of-the-art electron microscope. The image was taken from an electron microscope shows SARS-CoV-2, the virus that causes COVID-19.
In Episode 280 Jeff Belanger and Ray Auger take a week off for the holidays and reintroduce you to an episode from that vault that originally aired in December of 2020. We head to Jericho, Vermont, in search of snow. In 1885, Wilson Bentley figured out a way to attach his camera to a microscope and capture the first close-up photograph of a snowflake. In the coming years he would photograph thousands of images showing the intricate beauty of these ice crystals. His images would be published around the world and even hang in art galleries proving no two flakes are alike and earning Bentley the title: Snowflake Man.
There's some magic here. A 2-minute animation shows the process of chromosome separation during cell division. An image from a light microscope slowly undulates beneath the video as we see a cell ready to divide. Then the animation kicks in. A chromosome on the video image is highlighted, as if emerging from a mist. As we zoom onto this chromosome, we begin to notice the spindle fibers pulling from both sides. The video slowly focuses in on the spindle, as we notice the intricate protein machinery knitting away to extend it. The reader cannot escape the overall impression of enormous complexity deep within the cell, as processes that take minutes in a cell require a dance of millions of molecular interactions. 2b1af7f3a8