LIGHT, SHADOWS AND REFLECTIONS.pptx
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Light enables us to see objects and comes from luminous sources like the sun and stars or non-luminous sources like candles when lit. Light travels in a straight line and when it hits an object, the object can be seen if the light is reflected into our eyes. Shadows are formed when light is blocked by an opaque object, and have properties like shape depending on the object and light source, and being black in color regardless of the object's color. Solar and lunar eclipses occur when the sun, moon, and earth are aligned so that one casts its shadow on another.
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The anterior chamber is bordered
anteriorly by the cornea
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It contains aqueous humor (0.25ml )
The depth of the anterior chamber is
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shallower in hyperopia
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Anterior chamber angle.pptx
The anterior chamber is bordered
anteriorly by the cornea
posteriorly by the iris diaphragm and the pupil
It contains aqueous humor (0.25ml )
The depth of the anterior chamber is
deeper in aphakia, pseudophakia, and myopia
shallower in hyperopia
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The document discusses properties of electromagnetic radiation including light. It explains that light travels in waves at different speeds in different materials and can be reflected, refracted, or absorbed. Shorter wavelengths like ultraviolet, x-rays, and gamma rays have more energy than longer wavelengths like infrared, microwaves, and radio waves. The document also describes how light travels in straight lines and is bent by lenses, forming shadows and rainbows.
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2) We see objects because they reflect light into our eyes, and shadows are formed when light is blocked.
3) Mirrors come in plane, convex, and concave shapes and can form real or virtual images depending on their shape and whether the light rays actually meet or appear to meet.
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The document discusses light sources and how light travels. The major natural light source is the sun. Light travels in straight lines and can be reflected, absorbed, or pass through objects. It is reflected off opaque objects, absorbed by some objects, and passes through transparent or translucent objects. The eyes see light that enters through the cornea and is focused on the retina, where light information is sent to the brain to be interpreted as vision. Shadows are formed when light is blocked by opaque objects. The position of the sun affects the length and location of shadows outside.
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2. Light interacts with matter in several ways including absorption, transmission, reflection, and scattering. Scattering of light in the eye causes issues like glare and reduces retinal image contrast.
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This is a lesson about shadows. I hope you learn a lot from all the text, photos, and videos I have added to the presentation. I hope you enjoy it!
Earth in the solar system
1. The document discusses the solar system and the Earth's place within it. It describes the sun as the center of the solar system and lists the nine planets in order of their distance from the sun.
2. The Earth is described as the third planet from the sun, with one moon. It is a unique planet that can support life due to conditions like liquid water and breathable air.
3. The solar system resides within the Milky Way galaxy, which is part of the larger universe.
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Alternate Wetting and Drying - Climate Smart Agriculture
Alternate Wetting and Drying - Climate Smart AgricultureInternational Food Policy Research Institute- South Asia Office
PPT on Alternate Wetting and Drying 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. 在线办理(salfor毕业证书)索尔福德大学毕业证毕业完成信一模一样
学校原件一模一样【微信：741003700 】《(salfor毕业证书)索尔福德大学毕业证》【微信：741003700 】学位证，留信认证（真实可查，永久存档）原件一模一样纸张工艺/offer、雅思、外壳等材料/诚信可靠,可直接看成品样本，帮您解决无法毕业带来的各种难题！外壳，原版制作，诚信可靠，可直接看成品样本。行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备。十五年致力于帮助留学生解决难题，包您满意。
本公司拥有海外各大学样板无数，能完美还原。
1:1完美还原海外各大学毕业材料上的工艺：水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠。文字图案浮雕、激光镭射、紫外荧光、温感、复印防伪等防伪工艺。材料咨询办理、认证咨询办理请加学历顾问Q/微741003700
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留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
5:凡事获得留信网入网的信息将会逐步更新到个人身份内，将在公安局网内查询个人身份证信息后，同步读取人才网入库信息
6:个人职称评审加20分
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8:在国家人才网主办的国家网络招聘大会中纳入资料，供国家高端企业选择人才
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We present the JWST discovery of SN 2023adsy, a transient object located in a host galaxy JADES-GS
+
53.13485
−
27.82088
with a host spectroscopic redshift of
2.903
±
0.007
. The transient was identified in deep James Webb Space Telescope (JWST)/NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) program. Photometric and spectroscopic followup with NIRCam and NIRSpec, respectively, confirm the redshift and yield UV-NIR light-curve, NIR color, and spectroscopic information all consistent with a Type Ia classification. Despite its classification as a likely SN Ia, SN 2023adsy is both fairly red (
�
(
�
−
�
)
∼
0.9
) despite a host galaxy with low-extinction and has a high Ca II velocity (
19
,
000
±
2
,
000
km/s) compared to the general population of SNe Ia. While these characteristics are consistent with some Ca-rich SNe Ia, particularly SN 2016hnk, SN 2023adsy is intrinsically brighter than the low-
�
Ca-rich population. Although such an object is too red for any low-
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cosmological sample, we apply a fiducial standardization approach to SN 2023adsy and find that the SN 2023adsy luminosity distance measurement is in excellent agreement (
≲
1
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) with
Λ
CDM. Therefore unlike low-
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Ca-rich SNe Ia, SN 2023adsy is standardizable and gives no indication that SN Ia standardized luminosities change significantly with redshift. A larger sample of distant SNe Ia is required to determine if SN Ia population characteristics at high-
�
truly diverge from their low-
�
counterparts, and to confirm that standardized luminosities nevertheless remain constant with redshift.
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Working at Markes International has really opened my eyes (and unfortunately my friends and family 🤣) to food safety and quality, especially with my recent application work on ethylene oxide and 2-chloroethanol residues in foodstuffs, as of the biggest global food recalls in history was and is still being implemented by the Rapid alert system for food and feed (RASFF) in 2021, for high levels of these carcinogenic compounds.
The cost of acquiring information by natural selection
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It's based on the first part of this research paper:
The cost of information acquisition by natural selection
Ryan Seamus McGee, Olivia Kosterlitz, Artem Kaznatcheev, Benjamin Kerr, Carl T. Bergstrom
bioRxiv 2022.07.02.498577; doi: https://doi.org/10.1101/2022.07.02.498577
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Storagedeteriorationisanyformoflossinquantityandqualityofbio-materials.
Themajorcausesofdeteriorationinstorage
•Physical
•Biological
•Mechanical
•Chemical
Storageonlypreservesquality.Itneverimprovesquality.
Itisadvisabletostartstoragewithqualityfoodproduct.Productwithinitialpoorqualityquicklydepreciates
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https://ashpc.eu/
JAMES WEBB STUDY THE MASSIVE BLACK HOLE SEEDS
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Summary Of transcription and Translation.pdf
Hello Everyone Here We are Sharing You with The process of protien Synthesis in very short points you will be Able to understand It Very well
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
ESA/ACT Science Coffee: Diego Blas - Gravitational wave detection with orbita...
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Speaker: Diego Blas (IFAE/ICREA)
Title: Gravitational wave detection with orbital motion of Moon and artificial
Abstract:
In this talk I will describe some recent ideas to find gravitational waves from supermassive black holes or of primordial origin by studying their secular effect on the orbital motion of the Moon or satellites that are laser ranged.Farming systems analysis: what have we learnt?.pptx
Presentation given at the official farewell of Prof Ken Gillet at Wageningen on 13 June 2024
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
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
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LIGHT, SHADOWS AND REFLECTIONS.pptx
- 2. What is it that enables you to see other things but is itself not visible? The answer is light.
- 3. NATURAL & HUMAN MADE SOURCES OF LIGHT Objects like the sun, stars, fireflies can produce their own light are natural sources of light. Objects like candle, bulb cannot produce their own light are human made sources of light.
- 4. The objects that produce their own light are called luminous objects and those that do not are called non luminous objects. Moon is a non luminous object. It shines because it reflects the light of the sun to us.
- 5. HOW DO WE SEE NON LUMINOUS OBJECTS? When light falls on a non luminous object such as a book, it gets reflected in different directions. When this reflected light reaches our eyes, we can see the object.
- 6. LIGHT TRAVELS IN A STRAIGHT LINE Take a bent tube and try to look at a candle with the help of this tube. We will not be able to see the candle. Now, take a straight tube and try to look at the same candle with the help of this tube. We will be able to see the candle clearly. This activity shows that light travels in a straight line. This property of light of travelling in straight lines is called rectilinear propagation of light.
- 8. SHADOWS A shadow is formed when light from a source is obstructed by an opaque object. A shadow is the area where no light falls. Therefore it is black.
- 9. PROPERTIES OF A SHADOW 1) The shape of the shadow depends on * The shape of the object * The position of the source of light 2) A screen is necessary to form a shadow. 3) No matter what the colour of the object, the colour of the shadow cast by it is always black. 4) Other than its shape, no details of the object can be seen on the shadow.
- 10. SOLAR ECLIPSE When the sun, the moon and the earth come in a straight line, with the moon in the middle, the shadow of the moon may fall on some portions of the earth. Then a solar eclipse can be seen from these areas on the earth. In the region where the sun will be blocked totally, a total solar eclipse can be seen. In the rest of the region where the sun will be partially blocked by the moon, a partial solar eclipse can be seen.
- 11. LUNAR ECLIPSE In a lunar eclipse, the shadow of the earth falls on the moon. When the sun, the earth and the moon come in a straight line, with the earth in the middle, the shadow of the earth falls on the moon.
- 12. PINHOLE CAMERA A pinhole camera is a device used to form the image of an object. It consists of a box with a very tiny hole on one of its sides. Light falls on the hole and an inverted image is formed on the side opposite to the hole.