MICROSCOPY
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The document discusses three types of microscopes: compound microscopes, scanning electron microscopes (SEM), and comparison microscopes. Compound microscopes have multiple lenses, including objective and ocular lenses, and produce magnified images of specimens. SEMs use electron beams to scan sample surfaces and produce higher resolution images than optical microscopes. Comparison microscopes have two connected microscopes that allow side-by-side comparison of specimens and were invented for firearm analysis.
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sufficient. For many items, such as ink lines, bloodstains or bullets, no treatment is required and the evidence may
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applications in larger, full service laboratories because of their wide range of magnification, high resolving power and
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ByOm Prakash
June 13, 2022
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on To Study Principles of Microscopy: Light Microscope, Phase Contrast Microscope & Electron Microscope
Aim: To study principles of Microscopy: Light Microscope, Phase Contrast Microscope & Electron Microscope
Table of Contents
THEORETICAL BACKGROUND:
Light Microscopy
History:
SIMPLE MICROSCOPE
Principles of Microscopy:
THE COMPOUND MICROSCOPE
Phase Contrast Microscope
Electron Microscopes
SCANNING ELECTRON MICROSCOPE (SEM)
Also Read
THEORETICAL BACKGROUND:
Light Microscopy
The light microscope is an instrument designed for the study of cells and tissues. It comprises of lenses that produce a magnified image of the object under study. The light microscope is considered to be a simple important invention that has contributed to the advancement of biological research.
History:
The ancient Greeks and Romans knew the use of Glass and quartz lenses. In the 14th century, spectacles and lenses were used to magnify objects. Galileo had constructed a microscope at the same time (1610). It was employed for the study of the arrangement of the compound eye of insects. Anton Von Leeuwenhoek (1674), the father of biology was the first to use the microscope for biological studies. His microscope has consisted of a single lens with a higher power of magnification. The compound microscope was constructed by Robert Hooke (1665) and is the forerunner of the present-day compound microscope.
SIMPLE MICROSCOPE
The simple microscope distinguishes between two points that are less than 0.1mm apart when placed at a normal viewing distance of 25cm. The two points appear as one and the eye fails to resolve or distinguish them as two distinct points. Another limitation of the human eye is that it cannot resolve any image less than 5µm.
A simple microscope consists of a single convex lens or a combination of lenses that functions as a convex lens. A convex lens magnifies the objects and also helps to produce a magnified image of a near object which appears to be at the distance of distinct vision.
The magnification obtained with a convex lens can be easily calculated by the formula
M = 25/f + 1
Where f= focal length, 25 is the distance of distinct vision in cm.
Principles of Microscopy:
1. Resolving power: It is defined as the capacity of the microscope to distinguish images of two pointed objects lying very close together. If two points are at a distance of more than 0.2 µm, they will appear as two points in the microscope.
2. Limit of resolution: It is defined as the minimum distance at which two objects appear as two distinct objects or entities. It can be calculated as:
Limit of Resolution: 0.61λ/NA = 0.61λ/n Sin θ
Where 0.61 is the constant representing the minimum detectable difference in contrast λ = wavelength of illumination
NA = Numerical aperture, light gathering capa
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2) Electron microscopes, which use electron beams rather than light and have much higher resolutions of 1-10nm. Scanning electron microscopes provide 3D images while transmission electron microscopes have higher magnification but only show black and white 2D images.
3) Other microscope types like binocular, darkfield, and phase contrast microscopes and their applications in biology research. Pre
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scanning Electron Microscopy with animation video is added for complete explanation this is very easy to understand
Microscope ppt
An instrument used to magnify objects that are hard to see or invisible to the naked eye. Optical microscopes consist of a lens or combination of lenses, while electron microscopes use beams of electrons. Common types of microscopes include simple microscopes using one lens, compound microscopes with at least two lenses, electron microscopes using electron beams, phase-contrast microscopes utilizing light differences, and interference microscopes creating two superimposed images.
Microscope ppt
An instrument used to magnify objects that are hard to see or invisible to the naked eye. Optical microscopes consist of a lens or combination of lenses while electron microscopes use beams of electrons. Common types of microscopes include simple microscopes using one lens, compound microscopes with at least two lenses, electron microscopes using electron beams, phase-contrast microscopes utilizing light differences, and interference microscopes creating two superimposed images.
Scanning Electron Microscopy (SEM)
The document discusses scanning electron microscopy (SEM). It describes SEM as using a beam of electrons to examine objects on a fine scale, yielding information about topography, morphology, composition, and crystal structure. It outlines the main parts of an SEM, including the electron gun, electromagnetic lenses, vacuum chamber, and detectors for secondary electrons, backscattered electrons, and X-rays. The document explains that SEM works by scanning a focused electron beam across the sample surface and detecting signals from emitted electrons and X-rays to form images at magnifications up to 200,000x and resolutions of 1-2 nm.
Stem
The scanning transmission electron microscope (STEM) uses a finely focused electron beam that scans across the sample in a raster pattern. The STEM provides atomic resolution imaging and analysis through detectors like the EELS spectrometer, bright-field detector, and annular dark-field detector. Scan coils are used to scan the beam across the sample, while the condenser lens demagnifies the electron crossover point for high magnification imaging. The STEM has various applications in materials science and biology for characterizing nano- and atomic-scale structures.
Techniques in cell biology by vinitha
This document discusses various microscopy techniques used in cell biology. It begins by defining microscopy as the use of microscopes to view small objects. Light microscopes use visible light and lenses to examine small specimens. Types of light microscopes include brightfield, darkfield, phase contrast, fluorescence, and confocal microscopes. Electron microscopes like scanning electron microscopes and transmission electron microscopes use electron beams instead of light to provide higher resolution images of cellular structures and components. Microscopy is a powerful tool that is widely used in research, education, and medical diagnostics to study tissues at the cellular level.
Microscope
Optical microscopes use visible light and lenses to magnify specimens up to around 1000x, commonly applied in biology and materials science. They provide ease of use and minimal sample preparation. In contrast, electron microscopes, employing a beam of electrons, offer much higher magnifications and resolutions, reaching into the nanoscale. Transmission electron microscopes reveal internal structures, while scanning electron microscopes produce detailed 3D surface images. However, electron microscopes necessitate elaborate sample preparation, limiting their application to thin, metal-coated specimens. They are essential for exploring ultrastructural details in fields like cell biology and materials science.
Scanning electron microscope
The document summarizes the key components and operating principles of a scanning electron microscope (SEM). It describes the electron gun that generates the electron beam, the condenser lenses that focus the beam, the scan coils that scan the beam across the sample, and various detectors that detect signals from the sample. It outlines applications in fields like biology, materials science, and forensics. Advantages include detailed imaging and versatile information from detectors, while disadvantages include high costs and specialized training required.
ELECTRON MICROSCOPE-1.pptx
This document lists the members of Group One for a microscopy course. It includes 9 students' names and registration numbers. The document then provides an overview of different types of microscopes, including light microscopes, electron microscopes, fluorescence microscopes, and dark field microscopes. It describes the basic setup, working principles, uses and comparisons of these microscopic techniques.
CNM.docx
Ultraviolet-visible (UV-Vis) spectroscopy analyzes samples by measuring the wavelengths of UV or visible light absorbed after passing through a sample. It can identify the composition and concentration of components in a sample. Scanning electron microscopes (SEM) produce magnified images of samples by scanning them with a focused electron beam, revealing information about the sample's physical features and composition. Atomic force microscopes (AFM) use a cantilever with a tip that interacts with and detects sample surfaces via intermolecular forces, enabling measurement of properties like height, friction, and magnetism at the atomic scale.
microscope- lecture 2.pptx
Research is "creative and systematic work undertaken to increase the stock of knowledge". It involves the collection, organization and analysis of evidence to increase understanding of a topic, characterized by a particular attentiveness to controlling sources of bias and error.
Microscope
A microscope is used to view objects too small for the naked eye. Key properties of a good microscope include good resolution, contrast, and magnification. Different types of microscopes like bright field, dark field, phase contrast, and fluorescence microscopes use various optical techniques to view stained or unstained specimens. Electron microscopes have much higher resolving power than light microscopes and are used to view ultrastructures. Proper use and care of microscopes is important for safety and longevity.
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Petroleum products
This document provides an overview of petroleum analysis techniques and instruments. It discusses the composition and products of petroleum including gasoline, kerosene, lubricating oil, and wax. Key analytical methods covered are distillation, density measurement, viscosity testing, and flash point determination. Instrumental techniques analyzed in depth include gas chromatography-mass spectrometry (GC-MS). GC-MS is described as a valuable tool that separates components through a gas chromatograph and then identifies them via their mass spectra in the mass spectrometer. The document concludes with applications and references for further reading.
Estimation of hair index from human hair
Human hair is commonly found evidence at crime scenes and can provide a link between a criminal and their crime. Analysis of hair, called trichology, is important in forensic investigations as hair can easily be left behind at a crime scene and adhere to surfaces. This document outlines the equipment and process used to estimate the hair index of a human hair sample, which involves mounting hair on a slide, treating it with hydrogen peroxide and hydrochloric acid, and examining it under a microscope to measure the medulla and cortex.
Barbiturates
Barbiturates are classified as CNS depressants and are often prescribed to treat conditions like anxiety, depression, and insomnia. They produce effects like sleepiness, nausea, and breathing problems when consumed, and in higher doses can cause coma or death. Barbiturates come in many colors and are also abused for their ability to produce euphoria and treat withdrawal symptoms from other drugs. They can be consumed orally or via other routes of administration. Tests like chromatography, spectroscopy, and color tests are used to qualitatively and quantitatively analyze samples suspected to contain barbiturates. The salt or acid form of the barbiturate present affects how it can be identified.
Drug abuse in sports
This document discusses the history and science of drug testing in sports. It provides background on the types of performance enhancing drugs used by athletes and their effects. It then describes the anti-doping agencies and rules established to regulate drug use in sports. The document outlines the banned substances and methods according to their classifications. It details the sample collection and testing process, including the analytical methods used to detect drugs in urine and blood samples. Finally, it mentions some notable doping cases that have occurred in sports over time.
Sex determination using anthropometric methods
This document summarizes methods for determining sex from skeletal remains using anthropometric analysis. It outlines key sexual dimorphisms in the skull, pelvis, and long bones that can be used to identify whether remains are from a male or female. For the skull, traits like robustness, orbital shape, and mastoid process size can indicate sex. In the pelvis, characteristics such as the subpubic angle, sciatic notch width, and pubic arch shape provide clues. Measurements and morphological features of long bones like the femur, tibia, humerus and ulna also differ between males and females. Anthropologists can use these multiple lines of evidence from the skeleton to assign sex with 90-95%
Introduction to Anthropology
This document is a submission from Manshwine Bandor, a student in the 4th semester of the 2nd year of a BSc program at Shree Vaishnav Vidyapeeth Vishwavidyalaya. The topic of the submission is Anthropology and it has been submitted to assistant professor Ketan Patil.
Anthropology
Human evolution is a gradual process that has occurred over a long period of time. Key stages included Dryopithecus, which is considered the common ancestor of apes and humans around 25 million years ago. Ramapithecus and Kenyapithecus, dated to between 12-5 million years ago, displayed traits that were ancestral to humans. Australopithecus, the first upright walking species around 4 million years ago, had a brain capacity of around 500cc. Homo habilis began making tools around 2.4 million years ago. Later species such as Homo erectus had larger brains and used fire. Homo sapiens emerged around 200,000 years ago, with modern humans
Theories of organic evolution
The document discusses theories of organic evolution, including Darwin's theory of evolution by natural selection and Lamarck's theory of inheritance of acquired characteristics. Darwin's theory proposes that organisms evolve over generations through natural selection of inheritable traits that aid survival and reproduction. Lamarck's theory suggests that organisms can pass on traits acquired in their lifetime to offspring, such as giraffes inheriting long necks from ancestors that stretched their necks to reach leaves. Modern understanding incorporates genetics and shows how random mutations in DNA can provide variation for natural selection to act upon.
Anthropology
This document discusses the field of anthropology and its branches. It begins by defining anthropology as the study of humans, their origins, and cultural variations throughout history. The document then outlines the major branches of anthropology, including socio-cultural anthropology, physical/biological anthropology, archaeological anthropology, linguistic anthropology, and applied anthropology. For each branch, it provides a brief description of the areas of focus and goals of study.
Study of Soil and Paint
This document provides information about soils and paints. It defines soil as a mixture of organic matter, minerals, gases, liquids, and organisms that support life. The four main components of soil are identified as minerals, water, organic matter, and gases. Key soil types like sand, silt, clay and loam are described. Methods for analyzing soils like determining moisture content and particle size distribution are outlined. The document also defines paint as a liquid that converts to a solid film after application. The main components of paint are identified as pigments, binders, liquids, and additives. Common types of paints like water-based and oil-based are described. Forensic analysis methods for soils and paints are mentioned
Microscope and its types
This document provides information about different types of microscopes. It discusses simple microscopes, which use a single lens for magnification, and their basic parts and working principle. Compound microscopes are then introduced as using multiple lenses to achieve higher magnification than is possible with a simple lens alone. The key parts of a compound microscope are described, including the eyepiece, objective lenses, body tube, arm, and focus adjustments. It explains that light from the illuminator passes through these parts to produce a magnified image for viewing.
History of firearms
The document outlines the 7 phases of development in firearms technology:
1. Cannon lock - An early matchlock design with a pan and touch hole for ignition.
2. Matchlock - Used a slow-burning match cord for ignition which had disadvantages of visibility and damp weather.
3. Wheel lock - The first self-igniting design using a rotating flint mechanism.
4. Snaphaunce - An early flintlock design with a spring-loaded flint arm for ignition.
5. Flintlock - Rapidly replaced earlier designs using flint and steel for reliable ignition.
6. Percussion lock - Introduced in 1820, it used fulminate of
Hair and fiber
Hairs and fibers are important forms of trace evidence that can provide clues in forensic investigations. Hair has a cuticle, cortex, and sometimes a medulla, and characteristics like these can be used to identify a sample's origin. Fiber analysis examines properties such as the fiber's structure, color, and chemical composition to determine its type (natural or synthetic) and match it to a potential source. Due to their tendency to shed easily, fibers are commonly found as trace evidence and can link a suspect to a crime scene or victim.
Hair and fiber
This document discusses hair and fibers in forensic science. It provides details on:
- The structure and composition of hair, including the cuticle, cortex, and medulla layers. Hair characteristics like color, length and shape can indicate where on the body it came from. Nuclear and mitochondrial DNA can be extracted from hair roots or cuticles.
- Fibers are long thin strands that can be spun into yarn and woven into fabrics. Matching unique fibers between a victim and suspect's clothing can provide evidence of contact.
- Both natural fibers like cotton and wool and synthetic fibers like nylon and polyester are important in forensic analysis and can be identified under a microscope.
Internal Ballistics
Internal ballistics refers to what occurs within a weapon's barrel from firing to bullet exit. Key phenomena include:
- Ignition starts when the firing pin strikes the primer, igniting propellant which burns to form high-pressure gas.
- Propellant combustion and barrel length impact velocity - short barrels require fast-burning powder while long barrels use progressive-burning powder.
- Atmospheric conditions like temperature affect ballistics, as ammunition is manufactured for a specific temperature range and velocities vary with temperature.
Expert Witness Testimony
The document discusses the role and types of expert witnesses. An expert witness is a person with specialized knowledge or experience in a particular field who provides expert testimony. They may provide opinions on matters like injury severity, sanity, machine failures, damages, and authenticating electronic evidence. Expert testimony is important in many civil and criminal cases. Experts have a responsibility to provide unbiased opinions. There are testifying experts who present in court and non-testifying experts who advise lawyers. In ballistics cases, expert opinions on matching bullets to guns involve subjective assessments.
Terminal ballistics
This document discusses terminal ballistics and the different types of injuries caused by firearms. Terminal ballistics is the study of bullet behavior once it impacts the target. Factors like velocity, mass, size, and shape of the bullet affect the degree of injury. Rifled firearms can cause injuries at contact range (muzzle touching body), close shot (within flame distance), and distant shots over 50cm away. Shotgun wounds depend on range, with contact shots causing discoloration and burns and long range shots rarely being fatal. Entry wounds from firearms show more tissue destruction than exit wounds, which tend to be everted with split flaps. Specific injuries include abrasion collars, contusion collars, tattooing, and blackening
Improvised Firearms
This document discusses various types of improvised firearms, also known as zip guns. It provides examples such as zip guns, pen guns, pipe guns, and guns disguised as everyday objects like flashlights, cell phones, cigarettes, briefcases, and keychains. It describes how some of these firearms are constructed in a rudimentary way from available materials to function as a weapon. The document cautions that these improvised firearms can be unstable and pose safety risks due to improper materials or assembly.
External ballistics
External ballistics deals with the flight path of a projectile from the moment it exits the barrel until impact with the target. The key factors that influence a projectile's trajectory are wind, vertical angle, and air density. Wind can cause horizontal deflection from crosswinds and vertical deflection from headwinds or tailwinds. The vertical angle of fire affects slant range and requires adjustments to hold-off points. Variations in air pressure, temperature, and humidity that determine air density also influence drag on the projectile and its trajectory.
External ballistics
The document discusses the factors that affect the trajectory of a bullet, including both internal and external factors. The main internal factors are the velocity of the projectile, spin of the bullet, angle of fire, structural features, and gravity. The main external factors are wind, air resistance, and the Coriolis effect. The trajectory takes the form of a parabola, being affected most significantly by the bullet's velocity, as well as air resistance and gravity acting upon it during flight.
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快速办理(UAM毕业证书)马德里自治大学毕业证学位证一模一样
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Ahota Beel, nestled in Sootea Biswanath Assam , is celebrated for its extraordinary diversity of bird species. This wetland sanctuary supports a myriad of avian residents and migrants alike. Visitors can admire the elegant flights of migratory species such as the Northern Pintail and Eurasian Wigeon, alongside resident birds including the Asian Openbill and Pheasant-tailed Jacana. With its tranquil scenery and varied habitats, Ahota Beel offers a perfect haven for birdwatchers to appreciate and study the vibrant birdlife that thrives in this natural refuge.
11.1 Role of physical biological in deterioration of grains.pdf
Storagedeteriorationisanyformoflossinquantityandqualityofbio-materials.
Themajorcausesofdeteriorationinstorage
•Physical
•Biological
•Mechanical
•Chemical
Storageonlypreservesquality.Itneverimprovesquality.
Itisadvisabletostartstoragewithqualityfoodproduct.Productwithinitialpoorqualityquicklydepreciates
SDSS1335+0728: The awakening of a ∼ 106M⊙ black hole⋆
Context. The early-type galaxy SDSS J133519.91+072807.4 (hereafter SDSS1335+0728), which had exhibited no prior optical variations during the preceding two decades, began showing significant nuclear variability in the Zwicky Transient Facility (ZTF) alert stream from December 2019 (as ZTF19acnskyy). This variability behaviour, coupled with the host-galaxy properties, suggests that SDSS1335+0728 hosts a ∼ 106M⊙ black hole (BH) that is currently in the process of ‘turning on’. Aims. We present a multi-wavelength photometric analysis and spectroscopic follow-up performed with the aim of better understanding the origin of the nuclear variations detected in SDSS1335+0728. Methods. We used archival photometry (from WISE, 2MASS, SDSS, GALEX, eROSITA) and spectroscopic data (from SDSS and LAMOST) to study the state of SDSS1335+0728 prior to December 2019, and new observations from Swift, SOAR/Goodman, VLT/X-shooter, and Keck/LRIS taken after its turn-on to characterise its current state. We analysed the variability of SDSS1335+0728 in the X-ray/UV/optical/mid-infrared range, modelled its spectral energy distribution prior to and after December 2019, and studied the evolution of its UV/optical spectra. Results. From our multi-wavelength photometric analysis, we find that: (a) since 2021, the UV flux (from Swift/UVOT observations) is four times brighter than the flux reported by GALEX in 2004; (b) since June 2022, the mid-infrared flux has risen more than two times, and the W1−W2 WISE colour has become redder; and (c) since February 2024, the source has begun showing X-ray emission. From our spectroscopic follow-up, we see that (i) the narrow emission line ratios are now consistent with a more energetic ionising continuum; (ii) broad emission lines are not detected; and (iii) the [OIII] line increased its flux ∼ 3.6 years after the first ZTF alert, which implies a relatively compact narrow-line-emitting region. Conclusions. We conclude that the variations observed in SDSS1335+0728 could be either explained by a ∼ 106M⊙ AGN that is just turning on or by an exotic tidal disruption event (TDE). If the former is true, SDSS1335+0728 is one of the strongest cases of an AGNobserved in the process of activating. If the latter were found to be the case, it would correspond to the longest and faintest TDE ever observed (or another class of still unknown nuclear transient). Future observations of SDSS1335+0728 are crucial to further understand its behaviour. Key words. galaxies: active– accretion, accretion discs– galaxies: individual: SDSS J133519.91+072807.4
Male reproduction physiology by Suyash Garg .pptx
Physiology of Male reproduction.
Video mentioned at page no. 23 as summary for better understanding
Anti-Universe And Emergent Gravity and the Dark Universe
Recent theoretical progress indicates that spacetime and gravity emerge together from the entanglement structure of an underlying microscopic theory. These ideas are best understood in Anti-de Sitter space, where they rely on the area law for entanglement entropy. The extension to de Sitter space requires taking into account the entropy and temperature associated with the cosmological horizon. Using insights from string theory, black hole physics and quantum information theory we argue that the positive dark energy leads to a thermal volume law contribution to the entropy that overtakes the area law precisely at the cosmological horizon. Due to the competition between area and volume law entanglement the microscopic de Sitter states do not thermalise at sub-Hubble scales: they exhibit memory effects in the form of an entropy displacement caused by matter. The emergent laws of gravity contain an additional ‘dark’ gravitational force describing the ‘elastic’ response due to the entropy displacement. We derive an estimate of the strength of this extra force in terms of the baryonic mass, Newton’s constant and the Hubble acceleration scale a0 = cH0, and provide evidence for the fact that this additional ‘dark gravity force’ explains the observed phenomena in galaxies and clusters currently attributed to dark matter.
Post translation modification by Suyash Garg
overview of PTM helps to the students who wants to clear their basics about it.
Sustainable Land Management - Climate Smart Agriculture
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PPT on Sustainable Land Management presented at the three-day 'Training and Validation Workshop on Modules of Climate Smart Agriculture (CSA) Technologies in South Asia' workshop on April 22, 2024.
Compositions of iron-meteorite parent bodies constrainthe structure of the pr...
Magmatic iron-meteorite parent bodies are the earliest planetesimals in the Solar System,and they preserve information about conditions and planet-forming processes in thesolar nebula. In this study, we include comprehensive elemental compositions andfractional-crystallization modeling for iron meteorites from the cores of five differenti-ated asteroids from the inner Solar System. Together with previous results of metalliccores from the outer Solar System, we conclude that asteroidal cores from the outerSolar System have smaller sizes, elevated siderophile-element abundances, and simplercrystallization processes than those from the inner Solar System. These differences arerelated to the formation locations of the parent asteroids because the solar protoplane-tary disk varied in redox conditions, elemental distributions, and dynamics at differentheliocentric distances. Using highly siderophile-element data from iron meteorites, wereconstruct the distribution of calcium-aluminum-rich inclusions (CAIs) across theprotoplanetary disk within the first million years of Solar-System history. CAIs, the firstsolids to condense in the Solar System, formed close to the Sun. They were, however,concentrated within the outer disk and depleted within the inner disk. Future modelsof the structure and evolution of the protoplanetary disk should account for this dis-tribution pattern of CAIs.
Alternate Wetting and Drying - Climate Smart Agriculture
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Presentation given at the official farewell of Prof Ken Gillet at Wageningen on 13 June 2024
JAMES WEBB STUDY THE MASSIVE BLACK HOLE SEEDS
The pathway(s) to seeding the massive black holes (MBHs) that exist at the heart of galaxies in the present and distant Universe remains an unsolved problem. Here we categorise, describe and quantitatively discuss the formation pathways of both light and heavy seeds. We emphasise that the most recent computational models suggest that rather than a bimodal-like mass spectrum between light and heavy seeds with light at one end and heavy at the other that instead a continuum exists. Light seeds being more ubiquitous and the heavier seeds becoming less and less abundant due the rarer environmental conditions required for their formation. We therefore examine the different mechanisms that give rise to different seed mass spectrums. We show how and why the mechanisms that produce the heaviest seeds are also among the rarest events in the Universe and are hence extremely unlikely to be the seeds for the vast majority of the MBH population. We quantify, within the limits of the current large uncertainties in the seeding processes, the expected number densities of the seed mass spectrum. We argue that light seeds must be at least 103 to 105 times more numerous than heavy seeds to explain the MBH population as a whole. Based on our current understanding of the seed population this makes heavy seeds (Mseed > 103 M⊙) a significantly more likely pathway given that heavy seeds have an abundance pattern than is close to and likely in excess of 10−4 compared to light seeds. Finally, we examine the current state-of-the-art in numerical calculations and recent observations and plot a path forward for near-future advances in both domains.
MICROBIAL INTERACTION PPT/ MICROBIAL INTERACTION AND THEIR TYPES // PLANT MIC...
MICROBIAL INTERACTION PPT/ MICROBIAL INTERACTION AND THEIR TYPES // PLANT MIC...ABHISHEK SONI NIMT INSTITUTE OF MEDICAL AND PARAMEDCIAL SCIENCES , GOVT PG COLLEGE NOIDA
Microbial interaction
Microorganisms interacts with each other and can be physically associated with another organisms in a variety of ways.
One organism can be located on the surface of another organism as an ectobiont or located within another organism as endobiont.
Microbial interaction may be positive such as mutualism, proto-cooperation, commensalism or may be negative such as parasitism, predation or competition
Types of microbial interaction
Positive interaction: mutualism, proto-cooperation, commensalism
Negative interaction: Ammensalism (antagonism), parasitism, predation, competition
I. Mutualism:
It is defined as the relationship in which each organism in interaction gets benefits from association. It is an obligatory relationship in which mutualist and host are metabolically dependent on each other.
Mutualistic relationship is very specific where one member of association cannot be replaced by another species.
Mutualism require close physical contact between interacting organisms.
Relationship of mutualism allows organisms to exist in habitat that could not occupied by either species alone.
Mutualistic relationship between organisms allows them to act as a single organism.
Examples of mutualism:
i. Lichens:
Lichens are excellent example of mutualism.
They are the association of specific fungi and certain genus of algae. In lichen, fungal partner is called mycobiont and algal partner is called
II. Syntrophism:
It is an association in which the growth of one organism either depends on or improved by the substrate provided by another organism.
In syntrophism both organism in association gets benefits.
Compound A
Utilized by population 1
Compound B
Utilized by population 2
Compound C
utilized by both Population 1+2
Products
In this theoretical example of syntrophism, population 1 is able to utilize and metabolize compound A, forming compound B but cannot metabolize beyond compound B without co-operation of population 2. Population 2is unable to utilize compound A but it can metabolize compound B forming compound C. Then both population 1 and 2 are able to carry out metabolic reaction which leads to formation of end product that neither population could produce alone.
Examples of syntrophism:
i. Methanogenic ecosystem in sludge digester
Methane produced by methanogenic bacteria depends upon interspecies hydrogen transfer by other fermentative bacteria.
Anaerobic fermentative bacteria generate CO2 and H2 utilizing carbohydrates which is then utilized by methanogenic bacteria (Methanobacter) to produce methane.
ii. Lactobacillus arobinosus and Enterococcus faecalis:
In the minimal media, Lactobacillus arobinosus and Enterococcus faecalis are able to grow together but not alone.
The synergistic relationship between E. faecalis and L. arobinosus occurs in which E. faecalis require folic acid
TOPIC OF DISCUSSION: CENTRIFUGATION SLIDESHARE.pptx
Centrifugation is a powerful technique used in laboratories to separate components of a heterogeneous mixture based on their density. This process utilizes centrifugal force to rapidly spin samples, causing denser particles to migrate outward more quickly than lighter ones. As a result, distinct layers form within the sample tube, allowing for easy isolation and purification of target substances.
fermented food science of sauerkraut.pptx
This ppt contains the production of a fermented food name - sauerkraut
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
Context. The observation of several L-band emission sources in the S cluster has led to a rich discussion of their nature. However, a definitive answer to the classification of the dusty objects requires an explanation for the detection of compact Doppler-shifted Brγ emission. The ionized hydrogen in combination with the observation of mid-infrared L-band continuum emission suggests that most of these sources are embedded in a dusty envelope. These embedded sources are part of the S-cluster, and their relationship to the S-stars is still under debate. To date, the question of the origin of these two populations has been vague, although all explanations favor migration processes for the individual cluster members. Aims. This work revisits the S-cluster and its dusty members orbiting the supermassive black hole SgrA* on bound Keplerian orbits from a kinematic perspective. The aim is to explore the Keplerian parameters for patterns that might imply a nonrandom distribution of the sample. Additionally, various analytical aspects are considered to address the nature of the dusty sources. Methods. Based on the photometric analysis, we estimated the individual H−K and K−L colors for the source sample and compared the results to known cluster members. The classification revealed a noticeable contrast between the S-stars and the dusty sources. To fit the flux-density distribution, we utilized the radiative transfer code HYPERION and implemented a young stellar object Class I model. We obtained the position angle from the Keplerian fit results; additionally, we analyzed the distribution of the inclinations and the longitudes of the ascending node. Results. The colors of the dusty sources suggest a stellar nature consistent with the spectral energy distribution in the near and midinfrared domains. Furthermore, the evaporation timescales of dusty and gaseous clumps in the vicinity of SgrA* are much shorter ( 2yr) than the epochs covered by the observations (≈15yr). In addition to the strong evidence for the stellar classification of the D-sources, we also find a clear disk-like pattern following the arrangements of S-stars proposed in the literature. Furthermore, we find a global intrinsic inclination for all dusty sources of 60 ± 20◦, implying a common formation process. Conclusions. The pattern of the dusty sources manifested in the distribution of the position angles, inclinations, and longitudes of the ascending node strongly suggests two different scenarios: the main-sequence stars and the dusty stellar S-cluster sources share a common formation history or migrated with a similar formation channel in the vicinity of SgrA*. Alternatively, the gravitational influence of SgrA* in combination with a massive perturber, such as a putative intermediate mass black hole in the IRS 13 cluster, forces the dusty objects and S-stars to follow a particular orbital arrangement. Key words. stars: black holes– stars: formation– Galaxy: center– galaxies: star formation
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MICROSCOPY
- 1. Compound microscope and Stereo microscope & Comparison microscope Submitted to- Ketan sir SVVV, Indore Submitted by- Isha Sahu
- 2. Compound microscope:- • Compound microscope is a microscope with more than one lense and its own line source. • In this type of microscope their are ocular lense in the binocular eye piece and objective lense in a rotating nose piece closer to the specimen.
- 3. • The three basic, structural components of a compound microscope are the head, base and arm. • Head/Body houses the optical parts in the upper part of the microscope • Base of the microscope supports the microscope and houses the illuminator • Arm connects to the base and supports the microscope head. It is also used to carry the microscope.
- 5. Construction of compound microscope are based on two types:- * Mechanical system * Optical system
- 6. The mechanical system is composed of six parts:- * Base * Arm * Stage * Body tube * Coarse adjustment * Fine adjustment
- 7. The optical system is made up of four types:- * illuminator * Condenser * Objective lens * Eyepiece or occular lense
- 8. SEM :- A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. The electron beam is scanned in a raster scan pattern, and the position of the beam is combined with the detected signal to produce an image.
- 9. Principles • The signals used by a scanning electron microscope to produce an image result from interactions of the electron beam with atoms at various depths within the sample. • Various types of signals are produced including secondary electrons (SE), reflected or back- scattered electrons (BSE), characteristic X-rays and light (cathodoluminescence)
- 10. Applications: • Gunshot residue analysis. • Firearms identification (bullet markings comparison) • Examination of paint particles and fibres. • Handwriting and print examination / forgery. • Counterfeit bank notes. • Trace comparisons.
- 11. Comparion microscope *A comparison microscope is a device used to observe side-by-side specimens. * It consists of two microscopes connected to an optical bridge, which results in a split view window.
- 13. History of comparison microscope. The comparison microscope was invented in the 1920s by American Army Colonel Calvin Goddard (1891–1955) who was working for the Bureau of Forensic Ballistics of the City of New York.
- 14. Comparison microscope in forensic :- The comparison microscope is used in forensic sciences to compare microscopic patterns and identify or deny their common origin. Without this device, the identification of toolmarks and firearms would be such a cumbersome process that it would be carried out on a very limited basis.
- 15. Conclusion:- • Each microscope lens is inscribed with a number signifying power. • The image that is viewed by the microscopiest will have the magnification that is equal to the product of the magnifying power of the objective and eyepiece lenses.
- 16. Reference • https://www.encyclopedia.com>science. • https://www.microscope.com • https://www.azom.com • https://en.m.wikipedia.org>wiki>comp.. • Arthur koehiler
- 17. Thank You