This document describes tissue staining techniques used in biology. It discusses how basic dyes like hematoxylin stain basophilic structures blue while acidic dyes like eosin stain acidophilic structures pink. The basic steps in staining and mounting tissue sections are also outlined, including deparaffinization, rehydration, staining, dehydration, clearing, and mounting. Specific protocols for hematoxylin and eosin staining are provided.
Recrystallization is the most convenient method for purifying organic compounds that are solids at room temperature.
Compounds obtained from natural sources, or from reaction mixtures, almost always contain impurities.
The impurities may include some combination of insoluble, soluble, and colored impurities. To obtain a pure compound these impurities must be removed.
Each type of impurity is removed in a separate step in the recrystallization procedure.
Recrystallization is the most convenient method for purifying organic compounds that are solids at room temperature.
Compounds obtained from natural sources, or from reaction mixtures, almost always contain impurities.
The impurities may include some combination of insoluble, soluble, and colored impurities. To obtain a pure compound these impurities must be removed.
Each type of impurity is removed in a separate step in the recrystallization procedure.
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
2. Staining is used to highlight important features of the tissue as well as to
enhance the tissue contrast.
3. Chemical features of tissue structures according to affinity to acid-
base stains:
1.Basophilic structures, are stained by basic dyes:
Basic dyes, example; Hematoxylin
Hematoxylin is positively charged dye
Basophilic structures are negatively charged (ex. DNA and RNA)
Basophilic = Blue
2.Acidophilic (eosinophilic)structures, are stained by acid dyes.
Acidic dyes, example; Eosin
Eosin is negatively charged dye
Acidophilic structures are positive (ex. Proteins and cytoplasm)
Eosinophilic = Pink
4.
5. The basic steps in staining and mounting paraffin
sections are as follows
1. Deparaffinization
2. Rehydration
4. Staining
5. Dehydration and clearing
6. Mounting
7. Permanent seal - After mounting the cover slip can be
ringed by clear nail polish for storage.
6. 1. Deparaffinization; removal of wax is done with xylol.
• It is essential to remove the wax completely, otherwise
subsequent stages will not be possible.
• At least 2 to 3 changes in xylol are given for suitable length of
time. Sections of this stage should appear clear and transparent.
• Presence of any patches indicates the presence of wax and
sections should be kept longer in the xylol.
7. 2. Rehydration; most of the stains used are aqueous or dilute
alcoholic solutions.
Hence it is essential to bring the section to water before the
stains are applied. The hydration is done with graded
alcohols from higher concentration to lower concentration
(descending).
Alcohol and acetone are miscible with xylol. First change is
made to absolute alcohol or acetone followed by 100%, 70%
alcohol and finally distilled water. Sections now should
appear opaque.
Presence of any clear areas are indicative of the presence of
xylol. To remove this xylol, sections should be returned to
absolute alcohol and rehydrated
8. Staining
3. Staining; various staining procedures are applied
from this hydrated stage.
The most common stain applied for histological
study is Haematoxylin and Eosin. Various types of
haematoxylin formulations are used.
Washing and rinsing of tissue sections is a
necessary part of most staining techniques.
It eliminates carrying over of one dye solution to the
next.
9. 4. Dehydration and clearing; dehydration is done is graded
alcohols or acetones from 70% to absolute alcohol or acetone.
Dehydrating alcohol and acetones can remove some of the stains.
Time has to be suitably modified to minimize fading of stains. Since
alcohol and acetone are miscible in xylol, it is used for clearing the
sections.
Any sections from which water has not been completely removed
would give a milky appearance after the first xylol.
Such sections should be returned to absolute alcohol and the
process repeated. Mounting is done after 2nd or 3rd xylol.
Dehydration and Clearing
10. 5. Cover slipping and mounting
Make quite sure that the sections are quite clear. Do not let the
section go dry before mounting
1. Hold the slide between the thumb and the forefinger of one
hand and wipe with a clean cloth both ends of the slides. Look
for the engraved number to make sure the side the sections is
present.
2. Clean carefully around the section and lay on a clean blotting
paper with section uppermost along with appropriate coverslip
which has already been polished.
3. Place a drop of mountant on the slide over coverslip. Amount
of mountant should be just enough. Invert the slide over the
coverslip and lower it so that it just adheres to the cover slip
quickly turn the slide over, then lay it on a flat surface to allow
the mountant to spread. Do not press or push the slide at all. It
can damage the section.
11. 4. After the mountant has spread to the edge of the coverslip
wipe around it for neatness. If proper care has been taken there
should be no air bubbles. If many are present, slide should be
returned to the xylol to remove the coverslip.
It will slip off and remounting is done. No attempt should be made
to pull the coverslip. Slight warming of the slide from below
will make the small air bubbles to escape from the slide of the
coverslip.
4. Coverslip should be in the center of the slide with neatly
written label on one slide.
