A scintillation counter is an instrument for detecting and measuring ionizing radiation by using the excitation effect of incident radiation on a scintillating material, and detecting the resultant light pulses or it can be defined as it is used to detect gamma rays and the presence of a particle. It can also measure the radiation in the scintillating medium, the energy loss, or the energy gain. The medium can be solid and liquid.
The phenomenon in which the nucleus of the atom of an element undergoes spontaneous and uncontrollable disintegration or decay and emit alpha, beta, or gamma rays
It is the property of some unstable atoms to spontaneously emit nuclear radiation to gain stability.
The heavy elements are called radioactive elements and rays emitted these elements are called radioactive rays.
The phenomenon of radioactivity is discovered by HENRI BACQUEREL IN 1896.
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha decay (α-decay), beta decay (β-decay), and gamma decay (γ-decay), all of which involve emitting one or more particles.
Radioimmunoassay allows for the measurement of wide range of materials of clinical and biological importance. This technique has a significant impact on medical diagnosis due to the ease with which the tests can be carried out, while assuring precision, specificity and sensitivity.
The radioimmunoassay technique, as the name implies, achieves sensitivity through the use of radionuclides and specificity that is uniquely associated with immunochemical reactions. It can detect substance from a range of Nano gram(ng) to Pico gram(pg).
An isotope is one of two or more atoms having the same atomic number but different mass numbers.
Unstable isotopes are called Radioisotopes.
uses of radioisotopes are many which are discussed in this slide.
A detail and straight forward information about th CD and ORD
and Also about the polarization of light i.e. plane polarized light and circular polarized light
Radioimmunoassay allows for the measurement of wide range of materials of clinical and biological importance. This technique has a significant impact on medical diagnosis due to the ease with which the tests can be carried out, while assuring precision, specificity and sensitivity.
The radioimmunoassay technique, as the name implies, achieves sensitivity through the use of radionuclides and specificity that is uniquely associated with immunochemical reactions. It can detect substance from a range of Nano gram(ng) to Pico gram(pg).
An isotope is one of two or more atoms having the same atomic number but different mass numbers.
Unstable isotopes are called Radioisotopes.
uses of radioisotopes are many which are discussed in this slide.
A detail and straight forward information about th CD and ORD
and Also about the polarization of light i.e. plane polarized light and circular polarized light
A Presentation on Solid and Liquid ScintillationAnshdhaNANDRA1
Solid and liquid scintillation are fundamental techniques in radiation detection, vital across scientific, medical, and industrial domains. Solid scintillation utilizes materials such as crystals or plastics doped with scintillating compounds. When ionizing radiation interacts with these materials, they emit photons, producing flashes of light proportional to the radiation's energy. Photomultiplier tubes or photodiodes then detect and amplify these light signals for analysis, enabling precise measurement of radiation levels and identification of radioactive isotopes.
Liquid scintillation, meanwhile, involves dissolving radioactive samples in organic solvents containing scintillating molecules. Radiation interactions within the liquid generate photons, which are similarly detected and analyzed for radiation quantification and isotopic identification. Liquid scintillation is particularly useful in radiometric dating, environmental monitoring, and biochemical assays due to its versatility and sensitivity.
Both solid and liquid scintillation techniques offer unparalleled sensitivity and efficiency in detecting various types of radiation, from alpha and beta particles to gamma rays. Their widespread application continues to drive advancements in radiation detection, supporting diverse fields from nuclear physics to medical imaging and beyond.
spectroscopy, classification of spectroscopy, history, UV-VIS spectrophotometer, principle, beer lambert law instrumentation, detector, single beam, double beam in time, double beam in space, application, merits, and demerits
it covers types of counter for measurem,ent of radioactive substances also cover about radioactivity its causes effects and types of radioactive pollution
it describes about electron beam characteristics and applications and it outlines the following topics introduction, E-beam processing, E-beam equipment and applications.
I'm delighted to share the PDFs of lab courses in Microbial Physiology and Microbial Genetics. These comprehensive resources cover essential topics in understanding the intricate workings of microbes at a physiological and genetic level. these PDFs provide a detailed roadmap for our laboratory explorations.
Microbial physiology is the study of the structure, growth factors, metabolic activities, nutritional requirements, and genetic composition of microorganismsThe microbial cells are extremely complex and in addition to oxygen and hydrogen they contain four other major elements such as carbon, nitrogen, phosphorus and sulphur. here are the notes on microbial physiology..Photosynthetic pigments are the molecules responsible for absorbing electromagnetic radiation, transferring the energy of the absorbed photons to the reaction center, and for photochemical conversion in the photosynthetic systems of organisms capable of photosynthesis.
Probability is the branch of mathematics concerning events and numerical descriptions of how likely they are to occur. The probability of an event is a number between 0 and 1; the larger the probability, the more likely an event is to occur.[note 1][1][2] The higher the probability of an event, the more likely it is that the event will occur. A simple example is the tossing of a fair (unbiased) coin. Since the coin is fair, the two outcomes ('heads' and 'tails') are both equally probable; the probability of 'heads' equals the probability of 'tails'; and since no other outcomes are possible, the probability of either 'heads' or 'tails' is 1/2 (which could also be written as 0.5 or 50%).
These concepts have been given an axiomatic mathematical formalization in probability theory, which is used widely in areas of study such as statistics, mathematics, science, finance, gambling, artificial intelligence, machine learning, computer science, game theory, and philosophy to, for example, draw inferences about the expected frequency of events. Probability theory is also used to describe the underlying mechanics and regularities of complex systems.
Plasmids are extrachromosomal DNA molecules. They are small, circular and have the ability to replicate autonomously. Replication of plasmid is not under the control of chromosomal DNA. They are mostly found in bacteria. Some of the eukaryotes like yeast and plants also contain plasmids.
Download Complete Chapter Notes of Biotechnology: Principles and Processes
Their ability to replicate independently makes plasmid a cloning vector in the recombinant DNA technology for transferring and manipulating genes.
Many antibiotic-resistant genes in bacteria are present in plasmids.
The size of plasmid varies from a few base pairs to thousands of bp.
Plasmids also get transferred from one bacterial cell to another by the process of conjugation.
Plasmids carrying a specific gene are introduced into bacterial cells, which multiply rapidly and the required DNA fragment is produced in larger quantities.
Plasmids are used to prepare recombinant DNA with the desired gene to transfer genes from one organism to another. This is known as genetic engineering.
Joshua Lederberg coined the term plasmid.
mutagen is a physical or chemical agent that permanently changes genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can cause cancer in animals, such mutagens can therefore be carcinogens, although not all necessarily are. All mutagens have characteristic mutational signatures with some chemicals becoming mutagenic through cellular processes.
The process of DNA becoming modified is called mutagenesis. Not all mutations are caused by mutagens: so-called "spontaneous mutations" occur due to spontaneous hydrolysis, errors in DNA replication, repair and recombination.
Discovery
The first mutagens to be identified were carcinogens, substances that were shown to be linked to cancer. Tumors were described more than 2,000 years before the discovery of chromosomes and DNA; in 500 B.C., the Greek physician Hippocrates named tumors resembling a crab karkinos (from which the word "cancer" is derived via Latin), meaning crab.[1] In 1567, Swiss physician Paracelsus suggested that an unidentified substance in mined ore (identified as radon gas in modern times) caused a wasting disease in miners,[2] and in England, in 1761, John Hill made the first direct link of cancer to chemical substances by noting that excessive use of snuff may cause nasal cancer.[3] In 1775, Sir Percivall Pott wrote a paper on the high incidence of scrotal cancer in chimney sweeps, and suggested chimney soot as the cause of scrotal cancer.[4] In 1915, Yamagawa and Ichikawa showed that repeated application of coal tar to rabbit's ears produced malignant cancer.[5] Subsequently, in the 1930s the carcinogen component in coal tar was identified as a polyaromatic hydrocarbon (PAH), benzo[a]pyrene.
Polyaromatic hydrocarbons are also present in soot, which was suggested to be a causative agent of cancer over 150 years earlier.
A genetically modified organism (GMO) is any organism whose genetic material has been altered using genetic engineering techniques. The exact definition of a genetically modified organism and what constitutes genetic engineering varies, with the most common being an organism altered in a way that "does not occur naturally by mating and/or natural recombination".[1] A wide variety of organisms have been genetically modified (GM), including animals, plants, and microorganisms.
Genetic modification can include the introduction of new genes or enhancing, altering, or knocking out endogenous genes. In some genetic modifications, genes are transferred within the same species, across species (creating transgenic organisms), and even across kingdoms.
Creating a genetically modified organism is a multi-step process. Genetic engineers must isolate the gene they wish to insert into the host organism and combine it with other genetic elements, including a promoter and terminator region and often a selectable marker. A number of techniques are available for inserting the isolated gene into the host genome. Recent advancements using genome editing techniques, notably CRISPR, have made the production of GMOs much simpler. Herbert Boyer and Stanley Cohen made the first genetically modified organism in 1973, a bacterium resistant to the antibiotic kanamycin. The first genetically modified animal, a mouse, was created in 1974 by Rudolf Jaenisch, and the first plant was produced in 1983. In 1994, the Flavr Savr tomato was released, the first commercialized genetically modified food. The first genetically modified animal to be commercialized was the GloFish (2003) and the first genetically modified animal to be approved for food use was the AquAdvantage salmon in 2015.
Nitrogen-fixing bacteria, microorganisms capable of transforming atmospheric nitrogen into fixed nitrogen (inorganic compounds usable by plants). More than 90 percent of all nitrogen fixation is effected by these organisms, which thus play an important role in the nitrogen cycle.
Two kinds of nitrogen-fixing bacteria are recognized. The first kind, the free-living (nonsymbiotic) bacteria, includes the cyanobacteria (or blue-green algae) Anabaena and Nostoc and genera such as Azotobacter, Beijerinckia, and Clostridium. The second kind comprises the mutualistic (symbiotic) bacteria; examples include Rhizobium, associated with leguminous plants (e.g., various members of the pea family); Frankia, associated with certain dicotyledonous species (actinorhizal plants); and certain Azospirillum species, associated with cereal grasses.
The symbiotic nitrogen-fixing bacteria invade the root hairs of host plants, where they multiply and stimulate formation of root nodules, enlargements of plant cells and bacteria in intimate association. Within the nodules the bacteria convert free nitrogen to ammonia, which the host plant utilizes for its development. To ensure sufficient nodule formation and optimum growth of legumes (e.g., alfalfa, beans, clovers, peas, soybeans), seeds are usually inoculated with commercial cultures of appropriate Rhizobium species, especially in soils poor or lacking in the required bacterium.
Ecosystems can be as large as a desert or as small as a puddle.
They contain biotic
or living parts, as well as abiotic factors
, or nonliving parts. Biotic factors include plants, animals, and other organisms.
Nonliving materials include water, rocks, soil, and sand.
Ecosystems are a chain of interactions between organisms and their environment.
Each organism has a "job" to do in the ecosystem. For example, plants have chloroplasts that enable them to harvest light energy. Then, they take carbon dioxide and water from their environment to convert them into sugar.
Many ecosystems become degraded through human impacts, such as soil loss, air and water pollution, habitat fragmentation
, water diversion, fire suppression, and introduced species
and invasive species
.
An ecosystem includes all the living things (plants, animals and organisms) in a given area, interacting with each other, and with their non-living environments (weather, earth, sun, soil, climate, atmosphere). In an ecosystem, each organism has its own niche or role to play.
L-Lysine is an essential amino acid that's produced by fermentation. The fermentation process uses selected strains of microorganisms that grow in a solution of glucose or molasses, ammonium compounds, inorganic salts, and other substances.
Industrial lysine fermentation is usually performed using large-scale tank fermenters. In production plants, lysine accumulates to a final titer of 170 g/L after 45 hours.
Lysine and other amino acids are commonly produced by fermentation using strains of heterotrophic bacteria, such as Escherichia coli and Corynebacterium glutamicum. C. glutamicum has been engineered to produce lysine with a yield of 0.31 g lysine/g sugar.
Lysine is involved in the production of hormones and energy. It's also important for calcium and immune function.
Amino acids are small molecules that are the building blocks of proteins. Proteins serve as structural support inside the cell and they perform many vital chemical reactions. Each protein is a molecule made up of different combinations of 20 types of smaller, simpler amino acids.The pathways of amino acid synthesis comprise a significant fraction of a bacterium's metabolic activity during its growth in a minimal medium. Two amino acids, glutamine and glutamate, are the immediate products of ammonia assimilation and essential nitrogen donors for the synthesis of other intermediates.
Nutrition is substances used in biosynthesis and energy production and therefore are required for all living things.
Bacteria, like all living cells, require energy and nutrients to build proteins and structural membranes and drive biochemical processes.
Bacteria require sources of carbon, nitrogen, phosphorous, iron and a large number of other molecules.
Carbon, nitrogen, and water are used in the highest quantities.
The nutritional requirements for bacteria can be grouped according to the carbon source and the energy source.
Some types of bacteria must consume pre-formed organic molecules to obtain energy, while other bacteria can generate their own energy from inorganic sources.
Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species.The defining feature of this fungal group is the "ascus" (from Ancient Greek ἀσκός (askós) 'sac, wineskin'), a microscopic sexual structure in which nonmotile spores, called ascospores, are formed. However, some species of the Ascomycota are asexual, meaning that they do not have a sexual cycle and thus do not form asci or ascospores. Familiar examples of sac fungi include morels, truffles, brewers' and bakers' yeast, dead man's fingers, and cup fungi. The fungal symbionts in the majority of lichens (loosely termed "ascolichens") such as Cladonia belong to the Ascomycota.
Ascomycota is a monophyletic group (it contains all descendants of one common ancestor). Previously placed in the Deuteromycota along with asexual species from other fungal taxa, asexual (or anamorphic) ascomycetes are now identified and classified based on morphological or physiological similarities to ascus-bearing taxa, and by phylogenetic analyses of DNA sequences.
A fungus or funguses is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which, by one traditional classification, includes Plantae, Animalia, Protozoa, and Chromista.
A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the Eumycota (true fungi or Eumycetes), that share a common ancestor (i.e. they form a monophyletic group), an interpretation that is also strongly supported by molecular phylogenetics. This fungal group is distinct from the structurally similar myxomycetes (slime molds) and oomycetes (water molds). The discipline of biology devoted to the study of fungi is known as mycology (from the Greek μύκης mykes, mushroom). In the past mycology was regarded as a branch of botany, although it is now known that fungi are genetically more closely related to animals than to plants.
Abundant worldwide, most fungi are inconspicuous because of the small size of their structures, and their cryptic lifestyles in soil or on dead matter. Fungi include symbionts of plants, animals, or other fungi and also parasites. They may become noticeable when fruiting, either as mushrooms or as molds. Fungi perform an essential role in the decomposition of organic matter and have fundamental roles in nutrient cycling and exchange in the environment. They have long been used as a direct source of human food, in the form of mushrooms and truffles; as a leavening agent for bread; and in the fermentation of various food products, such as wine, beer, and soy sauce. Since the 1940s, fungi have been used for the production of antibiotics, and, more recently, various enzymes produced by fungi are used industrially and in detergents. Fungi are also used as biological pesticides to control weeds, plant diseases, and insect pests. Many species produce bioactive compounds called mycotoxins, such as alkaloids and polyketides, that are toxic to animals, including humans. The fruiting structures of a few species contain psychotropic compounds and are consumed recreationally or in traditional spiritual ceremonies. Fungi can break down manufactured materials and buildings, and become significant pathogens of humans and other animals. Losses of crops due to fungal diseases (e.g., rice blast disease) or food spoilage can have a large impact on
Basidiomycetes
Also known as club fungi.
The reproductive structure is basidium.
Spores that are produced are called basidiospores.
The vegetative structure is made up of primary or secondary mycelium.
Vegetative reproduction is done by fragmentation.
Sexual reproduction is done by the two vegetative or somatic cells creating a basidium.
Basidiospores are produced in the basidium by the development of fruiting bodies called basidiocarps.
Examples – Agaricus (found in mushrooms), Puccinia.
Basidiomycetes include these groups: mushrooms, puffballs, jelly fungi, boletes, chanterelles, earth stars, smuts, rusts, mirror yeasts, and Cryptococcus, the human pathogenic yeast.
Lipid metabolism is the synthesis and degradation of lipids in cells, involving the breakdown and storage of fats for energy and the synthesis of structural and functional lipids, such as those involved in the construction of cell membranes. In animals, these fats are obtained from food and are synthesized by the liver. Lipogenesis is the process of synthesizing these fats. The majority of lipids found in the human body from ingesting food are triglycerides and cholesterol.[4] Other types of lipids found in the body are fatty acids and membrane lipids. Lipid metabolism is often considered as the digestion and absorption process of dietary fat; however, there are two sources of fats that organisms can use to obtain energy: from consumed dietary fats and from stored fat.[5] Vertebrates (including humans) use both sources of fat to produce energy for organs such as the heart to function. Since lipids are hydrophobic molecules, they need to be solubilized before their metabolism can begin. Lipid metabolism often begins with hydrolysis, which occurs with the help of various enzymes in the digestive system.Lipid metabolism also occurs in plants, though the processes differ in some ways when compared to animals.[8] The second step after the hydrolysis is the absorption of the fatty acids into the epithelial cells of the intestinal wall.[6] In the epithelial cells, fatty acids are packaged and transported to the rest of the body.[9]
Metabolic processes include lipid digestion, lipid absorption, lipid transportation, lipid storage, lipid catabolism, and lipid biosynthesis. Lipid catabolism is accomplished by a process known as beta oxidation which takes place in the mitochondria and peroxisome cell organelles.
A DNA polymerase is a member of a family of enzymes that catalyze the synthesis of DNA molecules from nucleoside triphosphates, the molecular precursors of DNA. These enzymes are essential for DNA replication and usually work in groups to create two identical DNA duplexes from a single original DNA duplex. During this process, DNA polymerase "reads" the existing DNA strands to create two new strands that match the existing ones.[1][2][3][4][5][6] These enzymes catalyze the chemical reaction
deoxynucleoside triphosphate + DNAn ⇌ pyrophosphate + DNAn+1.
DNA polymerase adds nucleotides to the three prime (3')-end of a DNA strand, one nucleotide at a time. Every time a cell divides, DNA polymerases are required to duplicate the cell's DNA, so that a copy of the original DNA molecule can be passed to each daughter cell. In this way, genetic information is passed down from generation to generation.
Before replication can take place, an enzyme called helicase unwinds the DNA molecule from its tightly woven form, in the process breaking the hydrogen bonds between the nucleotide bases. This opens up or "unzips" the double-stranded DNA to give two single strands of DNA that can be used as templates for replication in the above reaction.
Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique to observe local magnetic fields around atomic nuclei. This spectroscopy is based on the measurement of absorption of electromagnetic radiations in the radio frequency region from roughly 4 to 900 MHz. Absorption of radio waves in the presence of magnetic field is accompanied by a special type of nuclear transition, and for this reason, such type of spectroscopy is known as Nuclear Magnetic Resonance Spectroscopy.[1] The sample is placed in a magnetic field and the NMR signal is produced by excitation of the nuclei sample with radio waves into nuclear magnetic resonance, which is detected with sensitive radio receivers. The intramolecular magnetic field around an atom in a molecule changes the resonance frequency, thus giving access to details of the electronic structure of a molecule and its individual functional groups. As the fields are unique or highly characteristic to individual compounds, in modern organic chemistry practice, NMR spectroscopy is the definitive method to identify monomolecular organic compounds.
The principle of NMR usually involves three sequential steps:
The alignment (polarization) of the magnetic nuclear spins in an applied, constant magnetic field B0.
The perturbation of this alignment of the nuclear spins by a weak oscillating magnetic field, usually referred to as a radio-frequency (RF) pulse.
Detection and analysis of the electromagnetic waves emitted by the nuclei of the sample as a result of this perturbation.
Similarly, biochemists use NMR to identify proteins and other complex molecules. Besides identification, NMR spectroscopy provides detailed information about the structure, dynamics, reaction state, and chemical environment of molecules. The most common types of NMR are proton and carbon-13 NMR spectroscopy, but it is applicable to any kind of sample that contains nuclei possessing spin.
NMR spectra are unique, well-resolved, analytically tractable and often highly predictable for small molecules. Different functional groups are obviously distinguishable, and identical functional groups with differing neighboring substituents still give distinguishable signals. NMR has largely replaced traditional wet chemistry tests such as color reagents or typical chromatography for identification. A disadvantage is that a relatively large amount, 2–50 mg, of a purified substance is required, although it may be recovered through a workup. Preferably, the sample should be dissolved in a solvent, because NMR analysis of solids requires a dedicated magic angle spinning machine and may not give equally well-resolved spectra. The timescale of NMR is relatively long, and thus it is not suitable for observing fast phenomena, producing only an averaged spectrum. Although large amounts of impurities do show on an NMR spectrum, better methods exist for detecting impurities.
Lyophilization or freeze drying is a process in which water is removed from a product after it is frozen and placed under a vacuum, allowing the ice to change directly from solid to vapor without passing through a liquid phase. The process consists of three separate, unique, and interdependent processes; freezing, primary drying (sublimation), and secondary drying (desorption).
The advantages of lyophilization include:
Ease of processing a liquid, which simplifies aseptic handling
Enhanced stability of a dry powder
Removal of water without excessive heating of the product
Enhanced product stability in a dry state
Rapid and easy dissolution of reconstituted product
Disadvantages of lyophilization include:
Increased handling and processing time
Need for sterile diluent upon reconstitution
Cost and complexity of equipment
The lyophilization process generally includes the following steps:
Dissolving the drug and excipients in a suitable solvent, generally water for injection (WFI).
Sterilizing the bulk solution by passing it through a 0.22 micron bacteria-retentive filter.
Filling into individual sterile containers and partially stoppering the containers under aseptic conditions.
Transporting the partially stoppered containers to the lyophilizer and loading into the chamber under aseptic conditions.
Freezing the solution by placing the partially stoppered containers on cooled shelves in a freeze-drying chamber or pre-freezing in another chamber.
Applying a vacuum to the chamber and heating the shelves in order to evaporate the water from the frozen state.
Complete stoppering of the vials usually by hydraulic or screw rod stoppering mechanisms installed in the lyophilizers.
There are many new parenteral products, including anti-infectives, biotechnology derived products, and in-vitro diagnostics which are manufactured as lyophilized products. Additionally, inspections have disclosed potency, sterility and stability problems associated with the manufacture and control of lyophilized products. In order to provide guidance and information to investigators, some industry procedures and deficiencies associated with lyophilized products are identified in this Inspection Guide.
It is recognized that there is complex technology associated with the manufacture and control of a lyophilized pharmaceutical dosage form. Some of the important aspects of these operations include: the formulation of solutions; filling of vials and validation of the filling operation; sterilization and engineering aspects of the lyophilizer; scale-up and validation of the lyophilization cycle; and testing of the end product. This discussion will address some of the problems associated with the manufacture and control of a lyophilized dosage form.
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.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
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
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
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?
Francesca Gottschalk - How can education support child empowerment.pptx
SOLID SCINTILLATION WRITE UP.docx
1. 1
GOVERNMENPT NAGARJUNA P.G. COLLEGE
OF SCIENCE RAIPUR (C.G.)
M.Sc. MICROBIOLOGY
SEMESTER - 2
2022-23
WRITE UP ON
SOLID SCINTILLATION COUNTER
SUBMITTED BY :- SUBMITTED TO:-
SNEHA AGRAWAL DEPT.OF MICROBIOLOGY
2. 2
INDEX
RADIOACTIVITY
EXPERIMENT FOR RADIOACTIVITY
MEASUREMENT OF RADIOACTIVITY
SCINTILLATION COUNTER
HISTORY
TYPES
DIFFERENCE BETWEEN SOLID AND LIQUID SCINTILLATION
COUNTER
SOLID SCINTILLATION COUNTER
PRINCIPLE
INSTRUMENTATION
WORKING
APPLICATION
ADVANTAGES
DISADVANTAGES
REFERENCE
3. 3
RADIOACTIVITY
The phenomenon in which the nucleus of the atom of an
element undergoes spontaneous and uncontrollable
disintegration or decay and emit alpha, beta, or gamma rays
It is the property of some unstable atoms to spontaneously emit
nuclear radiation to gain stability.
The heavy elements are called radioactive elements and rays
emitted these elements are called radioactive rays.
The phenomenon of radioactivity is discovered by HENRI
BACQUEREL IN 1896.
Radioactive decay (also known as nuclear
decay, radioactivity, radioactive disintegration, or nuclear
disintegration) is the process by which an unstable atomic
nucleus loses energy by radiation. A material containing unstable
nuclei is considered radioactive. Three of the most common types of
decay are alpha decay (α-decay), beta decay (β-decay), and gamma
decay (γ-decay), all of which involve emitting one or more particles.
EXPERIMENT FOR RADIOACTIVITY
In this experiment a radioactive substance is kept between the
two plates one is positively (+ve) charged and other is
negatively (-ve) charged.
It was observed that some radiations are attracted towards
negative (-ve) plate because they will have positive (+ve)
charge and are knows as alpha (α) rays.
Some are attracted towards positive (+ve) plate because
they will have negative (-ve) charged and are knows as beta (β) rays.
4. 4
Some radiation are neither attracted towards
positive (+ve) or negative (-ve) plate i.e. they are neutral charge and
are known as gamma (γ) rays
MESUREMENTS OF RADIOACTIVITY
The radioactivity of a substance can be measured by Becquerel
is the SI unit for measurement of radioactivity. It is defined as
the number of disintegration per second.
The radioactivity of radioactive substance is measured or
detected by instruments like :-
1. SCINTILLATION COUNTER
2. GAS FILLED CHAMBER
SCINTILLATION COUNTER
A scintillation counter is an instrument for detecting and measuring
ionizing radiation by using the excitation effect of incident radiation
on a scintillating material, and detecting the resultant light pulses
or it can be defined as it is used to detect gamma rays and the
presence of a particle. It can also measure the radiation in the
scintillating medium, the energy loss, or the energy gain. The
medium can be solid and liquid.
TYPES OF SCINTILLATION COUNTER
There are two types of scintillation counter based on the fluorescent
material used. They are:
1. solid scintillation counter
2. Liquid scintillation counter
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DIFFERENCE BETWEEN SOLID AND LIQUID
SCINTILLATION COUNTER
S.NO
.
SOLID SCINTILLATION
COUNTER
LIQUID SCINTILLATION
COUNTER
1. IT IS A RADIATION
DETECTOR WHICH
INCLUDES A
SCINTILLATION CRYSTAL TO
DETECT RADIATION AND
PRODUCES LIGHT PULSES.
IT IS A INSTRUMENT FOR
DETRMINING ACTIVITY OF A
LIQUID SAMPLE
2. USEFUL FOR GAMMA (γ)
EMITTING ISOTOPES.
USEFUL FOR QUANTIFYING ALPHA
(α) AND WEAK BETA (β) EMITTERS.
3. MOSTLY SCINTILLATOR
USED ARE INORGANIC
SCINTILLATORS AND
ORGANIC SCINTILLATORS.
HERE, IT CAN BE EITHER LIQUID
(ORGANIC SOLVENTS) OR SOLID
FORM (PLASTICS)
SOLID SCINTILLATION COUNTER
SOLID SCINTILLATION COUNTER (SSC) is an attractive
alternative and conventional instrument . With this method, a
sample is deposited directly onto a solid scintillating material, dried,
and counted in a scintillation counter. Solid scintillators have
several advantages. They are non volatile, toxic, or flammable, and
hence are safer to use. Waste disposal costs are reduced since the
sample is dried onto the solid scintillating material and may be
disposed of as solid waste.
The light emitted in scintillation can be detected by coupling it to
photomultiplier which convert the photon energy into an electrical
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pulse whose magnitude remains proportional to the energy of the
original radioactive event.
The crystal normally used are:
1. Sodium iodide : For gamma emitters
2. Zinc sulphide crystal : For alpha emitters
3. Anthracene : For beta emitters
HISTORY
The modern electronic scintillation counter was invented in 1944 by
sir samuel curran(UK). Previously scintillation events had to be
laboriously detected by eye using a spinthariscope which was a
simple microscope to observe light flashes in the scintillator.
PRINCIPLE
When high energy atomic radiations are incident on a surface
coated with some fluorescent material, then flashes of light (called
scintillation) are produced. The scintillation are detected with the
help of a photomultiplier tube , that gives rise to an equivalent
electric pulse.
These output electrical pulse can then be analyses
and counted electronically and gives rise to information regarding
the incident radiation. A solid scintillation counter is a radiation
detector which includes a scintillation crystal to detect radiation and
produce light pulses.
In the solid scintillation counters, the sample is placed in a vial, just
adjacent to a crystal or fluorescent material. Crystals are in turn
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placed near to the photomultiplier connected to a high voltage
supply and a scaler.
The solid scintillation counter is especially useful for gamma
emitting isotopes as these rays are electromagnetic radiation and
can collide well with the densely packed atoms of solid crystals.
The high atomic number and density of certain inorganic crystals
make them suitable for gamma spectroscopy with high detection
efficiencies.
SCINTILLATORS MAY BE CHARACTERISED INTO 2 MAIN
TYPES
1. ORGANIC SCINTILLATORS:-
A) Pure organic scintillators :- Anthracene, etc.
B) Liquid organic solutions :- pure organic scintillators
are dissolved in a suitable solvent &then we obtain liquid
organic scintillators.
C) Plastic scintillators :- pure organic scintillators after
dissolving in the solvent are subsequently polymerized.
2. INORGANIC SCINTILLATORS :-
NaI(Tl) :- Thallium activated Sodium Iodide
CsI(Tl) :- Thallium activated Cesium Iodide
CsI(Na) :- Sodium activated Cesium Iodide
INSTRUMENTATION
RADIATION- The high energy ionizing radiation strike the
crystal.
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SCINTILLATORS- It consist of a scintillator which generates
photons in response to incident radiation.
LIGHT FLASHES- Flash or rays of light produced in a
transparent material by passing a particle
PHOTOMULTIPLIER TUBE (PMT) –A sensitive
photomultiplier tube (PMT) which converts the light to an
electrical signal and electronics to process this signal.
PHOTOCATHODE- A photocathode is a surface that convert
light (photons) into electrons by photoelectric effect.
ELECTRICAL PULSE- A pulse may last from a fraction of a
nanosecond upto several seconds or even minutes.
AMPLIFIER- It is an electronic device that measures the
peak of potential pulse.
COUNTER- It measures the voltage of potential drop created
by the electrons.
WORKING
When ionizing incident radiation enters the scintillator, it interacts
with the material of the scintillator due to which the electrons enter
an excited state. Charged particles follow the path of the particle
itself. The energy of gamma radiation (uncharged) is converted to a
high energy electron either through the photoelectric effect.
The excited atoms of the scintillator material gradually
undergo de-excitation and emit photons in the visible range of light.
This emission is directly proportional to the energy of the incident
ionizing particle. The material shines or flows brightly due to
fluorescence.
The pulse of light emitted by the scintillator hits the
photocathode of the photomultiplier and releases at most one
photoelectron for each photon. These electrons are accelerated
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through electrostatic means by applying a voltage potential and are
targeted to hit the first dynode called the primary electrons. And
having enough energy to produce further electrons, these released
electrons are called secondary electrons. They strike the second
dynode, thereby releasing further electrons. This process occurs in a
photomultiplier tube. Each subsequent impact on the dynode
releases further electrons, and hence a current amplifying effect
occurs on the dynodes. Each subsequent dynode is at a higher
potential than the previous one, and so helps in enhancing the
acceleration. Likewise, the primary signal is multiplied throughout
10 to 12 stages. At the final dynode, highly sufficient numbers of
electrons are present to produce a pulse of high magnitude to
develop amplification. This pulse carries information about the
energy of the incident ionizing particle. The number of pulses per
unit time gives the significance of the intensity of radiation. And
finally counted in counter where it measures the voltage of
potential drop created by the electrons and saved the data for future
use.
APPLICATION
It is widely used in screening technologies, RIA alternative
technologies, cancer research, scientists, physicians, engineers
& technicians.
It also has its applications in protein interaction and detection,
academic research and pharmaceutical.
Border security ,nuclear plant safety, national and homeland
security
Used for the detection of alpha, beta and gamma emitters.
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ADVANTAGES
Its counting rate is very fast.
This instrument is also used to detect X-rays.
It can detect lower levels of radiation.
DISADVANTAGES
Hygroscopicity- A disadvantage of some inorganic crystals,
e.g. sodium iodide, is their hygroscopicity, a property which
requires them to be housed in an airtight container to protect
them from moisture.
The cost per sample of scintillation counter is significantly
higher.
The high voltage applied to the photomultiplier gives rise to
electronic events in the system which are not dependent on
radioactivity but which contribute to a high background count.
This effect is known as photomultiplier noise and can be
reduced by cooling the photmultiplier.
REFERANCE
BIOPHYSICAL CHEMISTRY PRINCIPLES AND
TECHNIQUES BY UPADHYAYA AND UPADHYAY AND
NATH.
A TEXTBOOK OF MICROBIOLOGY BBY R.C. DUBEY &
DR. D. K. MAHESHWARI.
https://www.researchgate.net/publication/263209531_Liquid_a
nd_solid_scintillation_principles_and_applications