All-digital histopathology by infrared-optical hybrid microscopy

Optical microscopy for biomedical samples requires expertise in staining to visualize structure and composition. Midinfrared (mid-IR) spectroscopic imaging offers label-free molecular recording and virtual staining by probing fundamental vibrational modes of molecular components. This quantitative signal can be combined with machine learning to enable microscopy in diverse fields from cancer diagnoses to forensics. However, absorption of IR light by common optical imaging components makes mid-IR light incompatible with modern optical microscopy and almost all biomedical research and clinical workflows. Here we conceptualize an IR-optical hybrid (IR-OH) approach that sensitively measures molecular composition based on an optical microscope with wide-field interferometric detection of absorption-induced sample expansion. We demonstrate that IR-OH exceeds state-of-the-art IR microscopy in coverage (10-fold), spatial resolution (fourfold), and spectral consistency (by mitigating the effects of scattering). The combined impact of these advances allows full slide infrared absorption images of unstained breast tissue sections on a visible microscope platform. We further show that automated histopathologic segmentation and generation of computationally stained (stainless) images is possible, resolving morphological features in both color and spatial detail comparable to current pathology protocols but without stains or human interpretation. IR-OH is compatible with clinical and research pathology practice and could make for a cost-effective alternative to conventional stain-based protocols for stainless, all-digital pathology.

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A simple cost-effective infra-red microscope for palynology

Journal of Micropalaeontology ◽

10.1144/jm.14.2.106 ◽

1995 ◽

Vol 14 (2) ◽

pp. 106-106 ◽

Cited By ~ 3

Author(s):

J. E. A. Marshall

Keyword(s):

Cost Effective ◽

Transmitted Light ◽

Silicon Chips ◽

Ir Microscopy ◽

Ir Imaging ◽

Sensitive Film ◽

Infra Red ◽

And Performance ◽

Halogen Bulb ◽

Ir Light

Abstract. It has long been known that objects which are opaque in transmitted white light can become translucent in infra-red (IR) light. Its application to palynology was shown by Leclercq (1933) who used an IR filter to cut out the visible light from the specimen coupled with an IR-sensitive film to capture the image. Although the significance of this development was recognized (Walton, 1935), it was never generally used since oxidative methods such as Schulze’s solution are normally successful in clearing exines. The exceptions are opaque palynomorphs from thermally over-mature rocks. Such assemblages have been studied with IR microscopy using either IR-sensitive film on partially cleared material (e.g. Tiwari & Schaarschmidt, 1975) or electronic IR imaging systems (Cramer & Diez, 1972).The technical sophistication and performance of IR imaging microscopes has recently improved significantly following their routine application for the internal imaging of silicon chips. However, such microscopes are designed for use in reflected light and also rather costly. In addition their design makes them difficult to routinely switch from brightfield transmitted light to IR light without risk of damaging their sensitive IR tube. This note describes a simplified IR microscope for transmitted light which shows how excellent images of opaque spores in the near-IR can be produced using the simplest palynological microscope.This IR microscope is based around an Olympus BHSM-IR system. This is fitted with a 100W quartz halogen bulb which is essential for providing the required level of IR illumination. However, the only specific IR corrected optics this. . .

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Label-Free, Real-Time Measurement of Metabolism of Adherent and Suspended Single Cells by In-Cell Fourier Transform Infrared Microspectroscopy

International Journal of Molecular Sciences ◽

10.3390/ijms221910742 ◽

2021 ◽

Vol 22 (19) ◽

pp. 10742

Author(s):

Tommaso Vannocci ◽

Luca Quaroni ◽

Antonio de Riso ◽

Giulia Milordini ◽

Magda Wolna ◽

...

Keyword(s):

Real Time ◽

Mammalian Cells ◽

Single Cells ◽

Adherent Cells ◽

Label Free ◽

Ir Microscopy ◽

Infrared Microspectroscopy ◽

Real Time Measurement ◽

Fourier Transform Infrared Microspectroscopy ◽

Molecular Components

We used infrared (IR) microscopy to monitor in real-time the metabolic turnover of individual mammalian cells in morphologically different states. By relying on the intrinsic absorption of mid-IR light by molecular components, we could discriminate the metabolism of adherent cells as compared to suspended cells. We identified major biochemical differences between the two cellular states, whereby only adherent cells appeared to rely heavily on glycolytic turnover and lactic fermentation. We also report spectroscopic variations that appear as spectral oscillations in the IR domain, observed only when using synchrotron infrared radiation. We propose that this effect could be used as a reporter of the cellular conditions. Our results are instrumental in establishing IR microscopy as a label-free method for real-time metabolic studies of individual cells in different morphological states, and in more complex cellular ensembles.

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Population Change, Modernization and Welfare. By Joseph Spengler. Prentice-Hall Inc., Englewood Cliffs, N.J. 1974.

The Pakistan Development Review ◽

10.30541/v16i2pp.220-222 ◽

1977 ◽

Vol 16 (2) ◽

pp. 220-222

Author(s):

Zeba A. Sathar

Keyword(s):

Population Growth ◽

Population Change ◽

Population Control ◽

Stable Condition ◽

Developed Countries ◽

Wide Field ◽

Wide Scale ◽

Socio Economic Variables ◽

Almost All

The book covers a wide field, touching on almost all aspects of popula¬tion change on a world-wide scale. It discusses, using world and country data, the relationships between demographic and socio-economic variables, and elaborates on" their relative importance in the determination of population problems which confront the world as a whole and nations individually. Policies designed to alleviate these problems are discussed with an emphasis on those related to population control. The first chapter is entitled "Population Growth: Past and Prospective" and reviews the various parameters associated with population change in the past and in the future. It touches upon the concept of a stable population in order to show the elements which cause a population to change (i.e. remove it from its stable condition). The main elements of change, population growth, migration, mortality and natality are discussed individually. The chapter is concluded by a description of the main differences in these elements and other socio-economic conditions as they exist in the less-developed and developed countries.

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Application of Natural Dye Obtained from Sweet Indrajao on Fabrics

Current Biochemical Engineering ◽

10.2174/2212711906999201020202052 ◽

2020 ◽

Vol 6 (3) ◽

pp. 180-191

Author(s):

Kavitha Chandrasekaran

Keyword(s):

Potassium Dichromate ◽

Bacterial Pathogens ◽

Ultrasonic Method ◽

Ferrous Sulphate ◽

Fine Powder ◽

Cost Effective ◽

Metal Salts ◽

Cow Dung ◽

Long Run ◽

Almost All

Background:: In the long run, synthetic tints were found to be harmful to the chemicals. As a result natural tints have come to be used for their many intrinsic values. The main reason being, then availability of local plants as the main source of natural colorants. Their easy availability in the country being zero cost – effective and planted for other purposes are the main reasons for utilizing them as natural tints. Almost all the parts of the plants, namely stem, leaves, fruits, seeds, barks etc. are used for extracting natural colour. In addition, they are antimicrobial antifungal, insect – repellant deodorant, disinfectant having medicinal values. Methods:: Sweet Indrajao leaves were cleaned by washing with water and dried under direct sunlight and ground as fine powder. A fine strainer was used to remove the wastages. After all these processes, 1-kilogram leaves weighed 318 grams. Then, it is put in 75% ethanol 25% water and heated in a breaker which in kept over a water bath for 2 hours. After this, the contents were filtered and kept in a separate beaker. Bleached fleece draperies stained with stain extract were made to become wet and put into different stain baths which contain the required amount of stain extract and water. Acetic acid was added to it after 20 minutes. The fleece drapery was stained for about one hour at 60oC. The draperies thus stained were removed, squeezed, and put to treatment with metal salts without washing. Different metal salts were used for the treatment using 3% of any one of the chemical mordants like alum, stannous chloride, potassium dichromate, ferrous sulphate, nickel sulphate, copper sulphate and natural mordants such as myrobolan, turmeric, cow dung, Banana sap juice at 60oC for 30 minutes with MLR of 1:30. The stained draperies were washed repeatedly in all the three methods in water and dried in air. At last, the stained draperies were put to soap with soap solution at 60oC for 10 minutes. The draperies were repeatedly washed in water and dried under the sun. Results:: Sweet Indrajao leaves discharged colour easily in alcoholic water. The fleece draperies were stained with chemical and natural mordants. It was observed that the stain uptake was found to be good in post-mordanting method. Ultrasonication has clearly improved the stainability of the draperies at pH 3 and 3.5 values. The pH decreases the stain ability under both Conventional and Ultrasonic conditions. The colour strength increases with an increase in staining temperature in both cases of US and CH methods. Conclusion:: Sweet Indrajao.L has been found to have good ultrasonic potential as a stain plant. The stain uptake as well as the fastness properties of the fleece drapery were found to enhance when metal mordant was used in conjugation with ultra-sonication for the extract of Sweet Indrajao. It was also found that the enhancement of staining ability was better without mordant draperies. The dye extract showed good antibacterial activity against the three bacterial pathogens. Among the three bacterial pathogens, dye extract showed more effective against Escherichia coli pathogens and dye extract showed more effective against Aspergillus pathogens. Hence, the ultrasonic method of drapery staining may be appropriate and beneficial for society at large in future.

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Utilising Commercially Fabricated Printed Circuit Boards as an Electrochemical Biosensing Platform

Micromachines ◽

10.3390/mi12070793 ◽

2021 ◽

Vol 12 (7) ◽

pp. 793

Author(s):

Uroš Zupančič ◽

Joshua Rainbow ◽

Pedro Estrela ◽

Despina Moschou

Keyword(s):

Printed Circuit Boards ◽

Electrochemical Sensors ◽

Cost Effective ◽

Electrochemical Sensing ◽

Label Free ◽

Circuit Boards ◽

Printed Circuit ◽

Sensing Applications ◽

Electrochemical Biosensing ◽

Pre Treatment

Printed circuit boards (PCBs) offer a promising platform for the development of electronics-assisted biomedical diagnostic sensors and microsystems. The long-standing industrial basis offers distinctive advantages for cost-effective, reproducible, and easily integrated sample-in-answer-out diagnostic microsystems. Nonetheless, the commercial techniques used in the fabrication of PCBs produce various contaminants potentially degrading severely their stability and repeatability in electrochemical sensing applications. Herein, we analyse for the first time such critical technological considerations, allowing the exploitation of commercial PCB platforms as reliable electrochemical sensing platforms. The presented electrochemical and physical characterisation data reveal clear evidence of both organic and inorganic sensing electrode surface contaminants, which can be removed using various pre-cleaning techniques. We demonstrate that, following such pre-treatment rules, PCB-based electrodes can be reliably fabricated for sensitive electrochemical biosensors. Herein, we demonstrate the applicability of the methodology both for labelled protein (procalcitonin) and label-free nucleic acid (E. coli-specific DNA) biomarker quantification, with observed limits of detection (LoD) of 2 pM and 110 pM, respectively. The proposed optimisation of surface pre-treatment is critical in the development of robust and sensitive PCB-based electrochemical sensors for both clinical and environmental diagnostics and monitoring applications.

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Plasma enhanced label-free immunoassay for alpha-fetoprotein based on a U-bend fiber-optic LSPR biosensor

RSC Advances ◽

10.1039/c5ra02910d ◽

2015 ◽

Vol 5 (31) ◽

pp. 23990-23998 ◽

Cited By ~ 37

Author(s):

Gaoling Liang ◽

Zhongjun Zhao ◽

Yin Wei ◽

Kunping Liu ◽

Wenqian Hou ◽

...

Keyword(s):

Surface Plasmon Resonance ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Localized Surface Plasmon Resonance ◽

Fiber Optic ◽

Cost Effective ◽

Alpha Fetoprotein ◽

Localized Surface Plasmon ◽

Label Free

A simple, label-free and cost-effective localized surface plasmon resonance (LSPR) immunosensing method was developed for detection of alpha-fetoprotein (AFP).

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Evaluation metrics and validation of presence-only species distribution models based on distributional maps with varying coverage

Scientific Reports ◽

10.1038/s41598-020-80062-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kamil Konowalik ◽

Agata Nosol

Keyword(s):

Ecological Niche Modeling ◽

Niche Modeling ◽

Ecological Niches ◽

Herbarium Specimens ◽

Wide Field ◽

Environmental Niche ◽

Endemic Plant ◽

Distribution Models ◽

Environmental Niche Modeling ◽

Almost All

AbstractWe examine how different datasets, including georeferenced hardcopy maps of different extents and georeferenced herbarium specimens (spanning the range from 100 to 85,000 km2) influence ecological niche modeling. We check 13 of the available environmental niche modeling algorithms, using 30 metrics to score their validity and evaluate which are useful for the selection of the best model. The validation is made using an independent dataset comprised of presences and absences collected in a range-wide field survey of Carpathian endemic plant Leucanthemum rotundifolium (Compositae). Our analysis of models’ predictive performances indicates that almost all datasets may be used for the construction of a species distributional range. Both very local and very general datasets can produce useful predictions, which may be more detailed than the original ranges. Results also highlight the possibility of using the data from manually georeferenced archival sources in reconstructions aimed at establishing species’ ecological niches. We discuss possible applications of those data and associated problems. For the evaluation of models, we suggest employing AUC, MAE, and Bias. We show an example of how AUC and MAE may be combined to select the model with the best performance.

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Label-Free Electrochemical Biosensor Based on Au@MoS₂–PANI for Escherichia coli Detection

Chemosensors ◽

10.3390/chemosensors9030049 ◽

2021 ◽

Vol 9 (3) ◽

pp. 49

Author(s):

Pushap Raj ◽

Man Hwan Oh ◽

Kyudong Han ◽

Tae Yoon Lee

Keyword(s):

Escherichia Coli ◽

Bacterial Infections ◽

Limit Of Detection ◽

Bacterial Pathogens ◽

Cost Effective ◽

Covalent Immobilization ◽

Label Free ◽

Self Assembled Monolayer ◽

Detection Range ◽

Linear Detection

Bacterial infections have become a significant challenge in terms of public health, the food industry, and the environment. Therefore, it is necessary to address these challenges by developing a rapid, cost-effective, and easy-to-use biosensor for early diagnosis of bacterial pathogens. Herein, we developed a simple, label-free, and highly sensitive immunosensor based on electrochemical detection using the Au@MoS₂–PANI nanocomposite. The conductivity of the glassy carbon electrode is greatly enhanced using the Au@MoS₂–PANI nanocomposite and a self-assembled monolayer of mercaptopropionic acid on the gold nanoparticle surface was employed for the covalent immobilization of antibodies to minimize the nonspecific adsorption of bacterial pathogens on the electrode surface. The biosensor established a high selectivity and sensitivity with a low limit of detection of 10 CFU/mL, and detected Escherichia coli within 30 min. Moreover, the developed biosensor demonstrated a good linear detection range, practical utility in urine samples, and electrode regenerative studies.

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