Editing Development of the human body

{{Short description|none}}
{{Redirect|Developmental|other uses|Development (disambiguation){{!}}Development}}
{{Human growth and development}}
'''Development of the human body''' is the process of [[Cell growth|growth]] to [[Adulthood|maturity]]. The process begins with [[Human fertilization|fertilization]], where an [[Egg cell|egg]] released from the [[ovary]] of a female is penetrated by a [[spermatozoan|sperm cell]] from a male. The resulting [[zygote]] develops through [[mitosis]] and [[cell differentiation]], and the resulting [[embryo]] then [[Implantation (human embryo)|implants]] in the [[uterus]], where the embryo continues development through a [[fetus|fetal stage]] until [[Childbirth|birth]]. Further growth and development continues after birth, and includes both [[physical development|physical]] and [[psychological development]] that is influenced by [[Genetics|genetic]], [[hormonal]], [[Biophysical environment|environmental]] and other factors. This continues throughout [[life]]: through [[childhood]] and [[adolescence]] into [[adulthood]].<ref>{{cite web|author=((The Editors of Encyclopaedia Britannica))|title=Human body/Basic form and development|url=https://www.britannica.com/science/human-body/Basic-form-and-development|website=Encyclopedia Britannica|access-date=2020-04-08|language=en|archive-date=2019-10-31|archive-url=https://web.archive.org/web/20191031154930/https://www.britannica.com/science/human-body/Basic-form-and-development|url-status=live}}</ref>

==Before birth==
{{Main|Prenatal development}}
Development before birth, or '''prenatal development''' ({{ety|la|natalis|relating to birth}}) is the process in which a [[zygote]], and later an [[embryo]], and then a [[fetus]] develops during [[gestation]]. [[Prenatal development]] starts with [[human fertilization|fertilization]] and the formation of the [[zygote]], the first stage in [[Human embryonic development|embryonic development]] which continues in fetal development until [[childbirth|birth]].

===Fertilization===
{{Main|Human fertilization}}
[[Image:Sperm-egg.jpg|right|thumb|Sperm fertilizing an egg]] 
Fertilization occurs when the sperm successfully enters the ovum's membrane. The [[chromosome]]s of the sperm are passed into the egg to form a unique genome. The egg becomes a [[zygote]] and the germinal stage of embryonic development begins. The germinal stage refers to the time from fertilization, through the development of the early embryo, up until implantation. The germinal stage is over at about 10 days of gestation.<ref name="germinal stage">{{cite web|title=Germinal stage|url=http://medical-dictionary.thefreedictionary.com/germinal+stage|work=Mosby's Medical Dictionary, 8th edition.|publisher=Elsevier.|access-date=6 October 2013|archive-date=28 April 2021|archive-url=https://web.archive.org/web/20210428005411/http://medical-dictionary.thefreedictionary.com/germinal+stage|url-status=live}}</ref>

The [[zygote]] contains a full complement of [[genetic material]] with all the biological characteristics of a single human being, and develops into the embryo. Embryonic development has four stages: the [[morula]] stage, the [[blastula]] stage, the [[gastrula]] stage, and the [[neurula]] stage. Prior to implantation, the [[embryo]] remains in a protein shell, the [[zona pellucida]], and undergoes a series of rapid mitotic cell divisions called [[cleavage (embryo)|cleavage]].<ref name="TortoraG">{{cite book |last1=Tortora |first1=G |last2=Derrickson |first2=B |title=Principles of anatomy & physiology |year=2012 |url=https://archive.org/details/principlesanatom00tort_737 |url-access=limited |publisher=Wiley |isbn=978-0470-91777-0 |page=[https://archive.org/details/principlesanatom00tort_737/page/n1218 1183]|edition=13th.}}</ref> A week after fertilization the embryo still has not grown in size, but hatches from the zona pellucida and adheres to the lining of the mother's [[uterus]]. This induces a [[decidual reaction]], wherein the uterine cells proliferate and surround the embryo thus causing it to become embedded within the uterine tissue. The embryo, meanwhile, proliferates and develops both into embryonic and extra-embryonic tissue, the latter forming the [[fetal membranes]] and the [[placenta]].  In humans, the embryo is referred to as a [[fetus]] in the later stages of prenatal development.  The transition from embryo to fetus is arbitrarily defined as occurring 8 weeks after fertilization. In comparison to the embryo, the fetus has more recognizable external features and a set of progressively developing internal organs. A nearly identical process occurs in other species.

===Embryonic development===
{{Main|Human embryonic development}}
[[Human embryonic development]] refers to the development and formation of the human [[embryo]]. It is characterised by the process of [[cell division]] and [[cellular differentiation]] of the [[embryo]] that occurs during the early stages of [[Human development (biology)|development]]. In biological terms, human development entails growth from a one-celled [[zygote]] to an adult [[human being]]. [[Fertilisation|Fertilization]] occurs when the [[sperm]] cell successfully enters and fuses with an egg cell ([[ovum]]).<ref name="germinal stage"/> The genetic material of the sperm and egg then combine to form a single cell called a zygote and the germinal stage of [[prenatal development]] commences. The embryonic stage covers the first eight weeks of development; at the beginning of the ninth week the embryo is termed a [[fetus]].

The germinal stage refers to the time from fertilization through the development of the early embryo until [[implantation (human embryo)|implantation]] is completed in the [[uterus]]. The germinal stage takes around 10 days.<ref name="germinal stage"/> During this stage, the zygote begins to divide, in a process called [[cleavage (embryo)|cleavage]]. A [[blastocyst]] is then formed and implanted in the [[uterus]]. Embryonic development continues with the next stage of [[gastrulation]], when the three [[germ layers]] of the embryo form in a process called [[histogenesis]], and the processes of [[neurulation]] and [[organogenesis]] follow.

In comparison to the embryo, the fetus has more recognizable external features and a more complete set of developing organs. The entire process of embryonic development involves coordinated spatial and temporal changes in [[gene expression]], [[cell growth]] and [[cellular differentiation]]. A nearly identical process occurs in other species, especially among [[chordate]]s.

===Fetal development===
{{Main|Fetus}}
A '''fetus''' is a stage in the human development considered to begin nine weeks after fertilization.<ref name="nursing">Klossner, N. Jayne, [https://books.google.com/books?id=B47OVg25g-QC&dq=fetal+stage+begins&pg=PA103 Introductory Maternity Nursing] (2005): "The fetal stage is from the beginning of the 9th week after fertilization and continues until birth"</ref><ref>{{cite web|url=http://www.americanpregnancy.org/duringpregnancy/fetaldevelopment1.htm|title=First Trimester |date=1 May 2012|website=American Pregnancy Association|url-status=live|archive-url=https://web.archive.org/web/20090423022520/http://www.americanpregnancy.org/duringpregnancy/fetaldevelopment1.htm|archive-date=23 April 2009}}</ref> In biological terms, however, prenatal development is a continuum, with many defining features distinguishing an embryo from a fetus. A fetus is also characterized by the presence of all the major body organs, though they will not yet be fully developed and functional and some not yet situated in their final location.
[[Image:Prenatal development table.svg|thumb|center|upright=3.5|Stages in [[prenatal development]]]]

===Maternal influences===
{{See also|Placenta}}
The fetus and embryo develop within the [[uterus]], an organ that sits within the pelvis of the [[mother]]. The process the mother experiences whilst carrying the fetus or embryo is referred to as [[pregnancy]]. The [[placenta]] connects the developing [[fetus]] to the [[Uterus|uterine]] wall to allow nutrient uptake, thermo-regulation, waste elimination, and gas exchange via the mother's blood supply; to fight against internal infection; and to produce hormones which support pregnancy. The placenta provides oxygen and nutrients to growing fetuses and removes waste products from the fetus' blood. The placenta attaches to the wall of the uterus, and the fetus' [[umbilical cord]] develops from the placenta. These organs connect the mother and the fetus.  Placentas are a defining characteristic of [[placental mammal]]s, but are also found in [[marsupials]] and some non-mammals with varying levels of development.<ref name="Pou92">Pough ''et al.'' 1992. Herpetology: Third Edition. Pearson Prentice Hall:Pearson Education, Inc., 2002.</ref> The [[Homology (biology)|homology]] of such structures in various [[Viviparity|viviparous organisms]] is debatable, and in invertebrates such as [[Arthropod]]a, is [[Analogy (biology)|analogous]] at best.

==After birth==
===Infancy and childhood===
{{Main|Infant|Child development|Child development stages}}
'''Childhood''' is the age span ranging from birth to [[adolescence]].<ref name="Students Macmillan 1981 page 173">''Macmillan Dictionary for Students'' Macmillan, Pan Ltd. (1981), page 173. Retrieved 2010-7-15.</ref> In [[developmental psychology]], childhood is divided up into the developmental stages of [[toddle]]rhood (learning to walk), [[early childhood]] (play age), middle childhood (school age), and adolescence (puberty through post-puberty). Various childhood factors could affect a person's attitude formation.<ref name="Students Macmillan 1981 page 173"/>

*Prepubescence 
** Neonate (newborn) 
**[[Infant]] (baby) 
**[[Toddler]] 
**[[Early childhood|Play age]] 
**[[Elementary school]] age, may coincide with [[preadolescence]] (preteen)
[[File:Child development stages.svg|thumb|center|800px|Approximate outline of development periods in [[child development]]]]

The [[Tanner stages]] can be used to approximately judge a child's age based on physical development.

{| class="wikitable" 
|- 
! For North American, Indo-Iranian (India, Iran) and European girls 
! For North American, Indo-Iranian (India, Iran) and European boys 
|- 
|  
*[[Thelarche]] (breast development) <br>age 10½ (8–13) 
*[[Pubarche]] (pubic hair) <br>age 11 (8½–13½) 
*Growth spurt <br>age 11¼ (10–12½) 
*[[Menarche]] (first menstrual bleeding) <br>age 12½ (10½–14½) 
*Wisdom tooth eruption<br>age 15½ (14–17)
*Adult [[Human height|height]] reached <br>age 15½ (14–17) 
|  
*[[Gonadarche]] (testicular enlargement) <br>age 11½ (9½–13½) 
*[[Pubarche]] (pubic hair) <br>age 12 (10–14) 
*Growth spurt <br>age 13 (11–15) 
*[[Spermarche]] (first ejaculation) <br>age 13 (11–15) 
*Wisdom tooth eruption <br>age 17 (15–19)
*Completion of growth <br>age 17 (15–19) 
|}

===Puberty===
{{Main|Puberty}}
'''Puberty''' is the process of physical changes through which a [[child]]'s [[Human body|body]] matures into an [[adult]] body capable of [[sexual reproduction]]. It is initiated by [[hormone|hormonal]] signals from the [[Human brain|brain]] to the [[gonad]]s: the [[ovary|ovaries]] in a girl, the [[testicle]]s in a boy. In response to the signals, the gonads produce hormones that stimulate [[libido]] and the growth, function, and transformation of the brain, [[bone]]s, [[muscle]], [[blood]], [[Human skin|skin]], [[human hair growth|hair]], [[breast]]s, and [[sex organ]]s. [[Human development (biology)|Physical growth]]—height and weight—accelerates in the first half of puberty and is completed when an adult body has been developed. Until the maturation of their reproductive capabilities, the pre-pubertal physical differences between boys and girls are the external sex organs.

On average, girls begin puberty around ages 10–11 and end puberty around 15–17; boys begin around ages 11–12 and end around 16–17.<ref name="Kail">{{cite book |last=Kail |first=RV |author2=Cavanaugh JC |title=Human Development: A Lifespan View |isbn=978-0495600374 |publisher=[[Cengage Learning]] |year=2010 |access-date=September 11, 2014 |page=296 |edition=5th |url=https://books.google.com/books?id=E-n5E7oyCgoC&pg=PA296 |archive-date=January 10, 2023 |archive-url=https://web.archive.org/web/20230110011825/https://books.google.com/books?id=E-n5E7oyCgoC&pg=PA296 |url-status=live }}</ref><ref name="pamf.org">"For girls, puberty begins around 10 or 11 years of age and ends around age 16. Boys enter puberty later than girls-usually around 12 years of age-and it lasts until around age 16 or 17." {{Cite news |url=http://www.pamf.org/parenting-teens/health/growth-development/pre-growth.html |title=Teenage Growth & Development: 11 to 14 Years |publisher=[[Palo Alto Medical Foundation]]/pamf.org |access-date=2013-11-09 |archive-date=2018-04-05 |archive-url=https://web.archive.org/web/20180405141025/http://www.pamf.org/parenting-teens/health/growth-development/pre-growth.html |url-status=live }}</ref><ref name="Pamf.org">{{Cite news |title=Teenage Growth & Development: 15 to 17 Years |publisher=[[Palo Alto Medical Foundation]]/pamf.org |url=http://www.pamf.org/parenting-teens/health/growth-development/growth.html |access-date=2013-11-09 |archive-date=2018-03-17 |archive-url=https://web.archive.org/web/20180317214045/http://www.pamf.org/parenting-teens/health/growth-development/growth.html |url-status=live }}</ref><ref name="Puberty">{{cite web |title=Puberty and adolescence |publisher=[[University of Maryland]] |url=http://umm.edu/health/medical/ency/articles/puberty-and-adolescence |archive-url=https://web.archive.org/web/20130924134845/http://umm.edu/health/medical/ency/articles/puberty-and-adolescence |access-date=December 8, 2020|archive-date=2013-09-24 }}</ref><ref name="Marshall17677">Marshall (1986), pp. 176–177{{Full citation needed|date=October 2022}}</ref> The major landmark of puberty for females is [[menarche]], the onset of menstruation, which occurs on average between ages 12 and 13;<ref name="Tanner">Tanner, 1990.{{Full citation needed|date=October 2022}}</ref><ref name="U.S. menarche">{{cite journal |vauthors=Anderson SE, Dallal GE, Must A|title=Relative weight and race influence average age at menarche: results from two nationally representative surveys of US girls studied 25 years apart |journal=Pediatrics |volume=111 |issue=4 Pt 1 |pages=844–850 |date=April 2003 |pmid=12671122 |doi=10.1542/peds.111.4.844 }}</ref><ref name="Canadian menarche">{{cite journal |vauthors=Al-Sahab B, Ardern CI, Hamadeh MJ, Tamim H|title=Age at menarche in Canada: results from the National Longitudinal Survey of Children & Youth |journal=BMC Public Health |volume=10 |page=736 |year=2010 |pmid=21110899 |pmc=3001737 |doi=10.1186/1471-2458-10-736 |doi-access=free }}</ref><ref name="UK menarche">{{cite book |url=http://vstudentworld.yolasite.com/resources/final_yr/gynae_obs/Hamilton%20Fairley%20Obstetrics%20and%20Gynaecology%20Lecture%20Notes%202%20Ed.pdf |title=Obstetrics and Gynaecology |series=Lecture Notes |first=Diana |last=Hamilton-Fairley |edition=Second |publisher=Blackwell Publishing |access-date=2013-11-09 |archive-date=2018-10-09 |archive-url=https://web.archive.org/web/20181009065351/http://vstudentworld.yolasite.com/resources/final_yr/gynae_obs/Hamilton%20Fairley%20Obstetrics%20and%20Gynaecology%20Lecture%20Notes%202%20Ed.pdf |url-status=dead }}</ref> for males, it is the first [[ejaculation]], which occurs on average at age 13.<ref name="Jorgensen & Keiding">Jorgensen & Keiding 1991.{{Full citation needed|date=October 2022}}</ref>  In the 21st century, the average age at which children, especially girls, reach puberty is lower compared to the 19th century, when it was 15 for girls and 16 for boys.<ref>{{cite news |url=https://www.telegraph.co.uk/health/healthnews/7824699/Girls-now-reaching-puberty-before-10-a-year-sooner-than-20-years-ago.html |archive-url=https://web.archive.org/web/20100614195534/http://www.telegraph.co.uk/health/healthnews/7824699/Girls-now-reaching-puberty-before-10-a-year-sooner-than-20-years-ago.html |url-status=dead |archive-date=2010-06-14 |location=London |work=[[The Daily Telegraph]] |first=Richard |last=Alleyne |title=Girls now reaching puberty before 10—a year sooner than 20 years ago |date=2010-06-13}}</ref> This can be due to any number of factors, including improved nutrition resulting in rapid body growth, increased weight and fat deposition,<ref name="Guillette_2006">{{cite journal |vauthors=Guillette EA, Conard C, Lares F, Aguilar MG, McLachlan J, Guillette LJ|title=Altered breast development in young girls from an agricultural environment |journal=Environ. Health Perspect. |volume=114 |issue=3 |pages=471–5 |date=March 2006 |pmid=16507474 |pmc=1392245 |doi=10.1289/ehp.8280 }}</ref> or exposure to [[endocrine disruptor]]s such as [[xenoestrogen]]s, which can at times be due to food consumption or other environmental factors.<ref name="Louis_2008">{{cite journal |vauthors=Buck Louis GM, Gray LE, Marcus M, Ojeda SR, Pescovitz OH, Witchel SF, Sippell W, Abbott DH, Soto A, Tyl RW, Bourguignon JP, Skakkebaek NE, Swan SH, Golub MS, Wabitsch M, Toppari J, Euling SY|title=Environmental factors and puberty timing: expert panel research needs |journal=[[Pediatrics (journal)|Pediatrics]] |volume=121 |issue=Suppl 3 |pages=S192–207 |date=February 2008 |pmid=18245512 |doi=10.1542/peds.1813E |doi-access=free }}</ref><ref name="Mouritsen_2010">{{cite journal |vauthors=Mouritsen A, Aksglaede L, Sørensen K, Mogensen SS, Leffers H, Main KM, Frederiksen H, Andersson AM, Skakkebaek NE, Juul A|title=Hypothesis: exposure to endocrine-disrupting chemicals may interfere with timing of puberty |journal=Int. J. Androl. |volume=33 |issue=2 |pages=346–59 |date=April 2010 |pmid=20487042 |doi=10.1111/j.1365-2605.2010.01051.x }}</ref> Puberty which starts earlier than usual is known as [[precocious puberty]], and puberty which starts later than usual is known as [[delayed puberty]].

Notable among the [[morphology (biology)|morphologic]] changes in size, shape, composition, and functioning of the pubertal body, is the development of [[secondary sex characteristic]]s, the "filling in" of the child's body; from girl to woman, from boy to man.{{Clarify|reason=What exactly does "filling in" involve, for female and for male bodies? What are the secondary sex characteristics?|date=October 2022}}

===Adulthood===
Biologically, an adult is a human or other organism that has reached sexual maturity. In human context, the term adult has additional meanings associated with social and legal concepts. In contrast to a [[Minor (law)|legal minor]], a legal adult is a person who has attained the age of majority and is therefore regarded as independent, self-sufficient, and responsible. The typical age of legal majority is 18 years in most contexts, although the definition of majority may vary by legal rights and country.

Human adulthood encompasses psychological adult development. Definitions of adulthood are often inconsistent and contradictory; an adolescent may be biologically an adult and display adult behavior but still be treated as a child if they are under the legal age of majority. Conversely, a legal adult may possess none of the maturity and responsibility that is supposed to define them; the mental and physical development and maturity of an individual has been proven to be greatly influenced by their life circumstances.

==Organ systems==
{{Main|Organogenesis}}
{{Organ system development}}
Human [[organ (biology)|organs]] and [[organ system]]s develop in a process known as [[organogenesis]]. This begins in the third week of embryonic development, when the gastrula forms three distinct [[germ layer]]s, the [[ectoderm]], [[mesoderm]] and [[endoderm]]. The ectoderm will eventually develop into the [[epidermis|outer layer of skin]] and [[development of the nervous system in humans|nervous system]]. The mesoderm will form [[myogenesis|skeletal muscles]], [[haematopoiesis|blood cells]], the [[development of the reproductive system|reproductive system]], the [[development of the urinary system|urinary system]], most of the [[circulatory system]], and the [[connective tissue]] of the torso. The endoderm will develop into the [[epithelium]] of the [[respiratory tract|respiratory]] and [[gastrointestinal tract]]s and several [[gland]]s.<ref>{{cite book |last1=Moore |first1=Keith L. |title=The Developing Human: Clinically Oriented Embryology |date=2020 |publisher=Elsevier |location=Edinburgh |isbn=978-0-323-61154-1 |pages=47–63 |edition=11th |chapter=Third Week of Human Development}}</ref>

== Linear growth ==
During childhood, the bones undergo a complex process of elongation that occurs in a specific area called the [[epiphyseal growth plates]] (EGP). This process is regulated by various [[hormone]]s and factors, including the growth hormone, vitamin D, and others. These hormones promote the production of insulin-like growth factor-1 (IGF-1), which plays a key role in the formation of new bone cells. Adequate [[nutrient intake]] is essential for the production of these hormones, which are critical for proper bone growth. However, a lack of proper nutrition can hinder this process and result in [[stunted growth]].

Linear growth takes place in the epiphyseal growth plates (EGP) of long bones.<ref name="Gat-Yablonski G p M">Gat-Yablonski G, Phillip M. Nutritionally-induced catch-up growth. Nutrients 2015; 7(1): 517–51.</ref> In the growth plate, [[chondrocyte]]s proliferate, hypertrophy and secrete cartilage extracellular matrix. New cartilage is subsequently remodeled into bone tissue, causing bones to grow longer.<ref>Kronenberg HM. Developmental regulation of the growth plate. Nature 2003; 423(6937): 332–6.</ref> Linear growth is a complex process regulated by the growth hormone (GH) – insulin-like growth factor-1 ([[Insulin-like growth factor 1|IGF-1]]) axis, the thyroxine/triiodothyronine axis, androgens, estrogens, vitamin D, glucocorticoids and possibly leptin.<ref name="ReferenceA">Millward DJ. Nutrition, infection and stunting: the roles of deficiencies of individual nutrients and foods, and of inflammation, as determinants of reduced linear growth of children. Nutr Res Rev 2017; 30(1): 50–72.</ref> GH is secreted by the anterior pituitary gland in response to hypothalamic, pituitary and circulating factors. It affects growth by binding to receptors in the EGP,<ref name="Gat-Yablonski G p M"/> and inducing production and release of IGF-1 by the liver.<ref>Le Roith D. The insulin-like growth factor system. Exp Diabesity Res 2003; 4(4): 205–12.</ref> IGF-1 has six binding proteins (IGFBPs), exhibiting different effects on body tissues, where [[IGFBP3|IGFBP-3]] is most abundant in human circulation.<ref>Rajaram S, Baylink DJ, Mohan S. Insulin-like growth factor-binding proteins in serum and other biological fluids: regulation and functions. Endocr Rev 1997; 18(6): 801–31.</ref> IGF-1 initiates growth through differentiation and maturation of osteoblasts, and regulates release of GH from the pituitary through feedback mechanisms.<ref>Daughaday WH. Growth hormone axis overview—somatomedin hypothesis. Pediatr Nephrol 2000; 14(7): 537–40.</ref> The GH/IGF-1 axis is responsive to dietary intake and infections. The endocrine system seems to allow for rapid growth only when the organism is able to consume sufficient amounts of nutrients and signaling from key nutrients such as amino acids and zinc to induce production of IGF-1 is present.<ref name="ReferenceA"/> At the same time inflammation and increased production of pro-inflammatory cytokines may cause GH resistance and a decrease in circulating IGF-1 and IGFBP-3 which in turn reduces endochondrial ossification and growth.<ref name="ReferenceA"/><ref>DeBoer MD, Scharf RJ, Leite AM, et al. Systemic inflammation, growth factors, and linear growth in the setting of infection and malnutrition. Nutrition 2017; 33: 248–53.</ref> However, the EGP appears to conserve much growth capacity to allow for catch-up growth.<ref>Lui JC, Nilsson O, Baron J. Growth plate senescence and catch-up growth. Endocr Dev 2011; 21: 23–9.</ref> Concerns have been raised about associations between catch-up growth and increased risk of non-communicable diseases in adulthood.<ref>Victora CG, Adair L, Fall C, et al. Maternal and child undernutrition: consequences for adult health and human capital. Lancet 2008; 371(9609): 340–57.</ref> In a large study based on 5 birth cohorts in Brazil, Guatemala, India, the Philippines and South Africa, faster linear growth at 0–2 years was associated with improvements in adult stature and school performance, but also an increased likelihood of overweight (mainly related to lean mass) and a slightly elevated blood pressure in young adulthood.<ref>Adair LS, Fall CH, Osmond C, et al. Associations of linear growth and relative weight gain during early life with adult health and human capital in countries of low and middle income: findings from five birth cohort studies. Lancet 2013; 382(9891): 525–34.</ref>

==See also==
* [[Auxology]]
* [[Developmental biology]]
* [[Human body]]
* [[Life-history theory]]
* [[List of youth-related terms]]
* [[Outline of human anatomy]]

== References ==
{{CC-notice|cc=bysa3|url=https://oda.oslomet.no/oda-xmlui/handle/10642/7102|author= Marianne Sandsmark Morseth}}
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