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Welcome to The Visible Embryo, a comprehensive educational resource on human development from conception to birth.

The Visible Embryo provides visual references for changes in fetal development throughout pregnancy and can be navigated via fetal development or maternal changes.

The National Institutes of Child Health and Human Development awarded Phase I and Phase II Small Business Innovative Research Grants to develop The Visible Embryo. Initally designed to evaluate the internet as a teaching tool for first year medical students, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than ' million visitors each month.


WHO International Clinical Trials Registry Platform
The World Health Organization (WHO) has created a new Web site to help researchers, doctors and patients obtain reliable information on high-quality clinical trials. Now you can go to one website and search all registers to identify clinical trial research underway around the world!



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Pregnancy Timeline by SemestersFetal liver is producing blood cellsHead may position into pelvisBrain convolutions beginFull TermWhite fat begins to be madeWhite fat begins to be madeHead may position into pelvisImmune system beginningImmune system beginningPeriod of rapid brain growthBrain convolutions beginLungs begin to produce surfactantSensory brain waves begin to activateSensory brain waves begin to activateInner Ear Bones HardenBone marrow starts making blood cellsBone marrow starts making blood cellsBrown fat surrounds lymphatic systemFetal sexual organs visibleFinger and toe prints appearFinger and toe prints appearHeartbeat can be detectedHeartbeat can be detectedBasic Brain Structure in PlaceThe Appearance of SomitesFirst Detectable Brain WavesA Four Chambered HeartBeginning Cerebral HemispheresFemale Reproductive SystemEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterSecond TrimesterFirst TrimesterFertilizationDevelopmental Timeline
Click weeks 0 - 40 and follow fetal growth
Google Search artcles published since 2007
 
August 26, 2011--------News Archive


A Question of Gene Silencing
Researchers have found a new way to selectively turn off genes that don't code for proteins which will help identify each gene's function, and perhaps identify cancers.

Scented Products Emit Hazardous Chemicals
Chemical sleuthing has uncovered that fragrance in consumer laundry products contains hazardous chemicals. Some which are even carcinogens.

August 25, 2011--------News Archive

Human Stem Cells Made From Amnionic Fluid
Human epithelial cells transplanted from human amnionic fluid reduce pulmonary fibrosis, and even stimulate lung regeneration in mice.

Scale Models Rule
Body patterns stay in sync with size as an embryo grows into an adult. Observed in the wing of the fruit fly, these patterns most likely exist in all organisms.

Chronic Disease Caused by Fat Cells?
Fat cells in people with metabolic syndrome have biomarkers for insulin resistance and chronic inflammation, conditions in diabetes and cardiovascular disease.

August 24, 2011--------News Archive

In the Early Life of An Embryo, Chaos Lurks
A calcium wave sparks embryonic cell division, doubling as a synchronizer of all further cell division in order for chaos to be reined in and ordered growth to persist.

Smoking Affects Fetal Infant Brain Worse than Feared
Researchers pin-point smoking specifically and find a 40% increase in damage to the fetus.

August 23, 2011--------News Archive

Boys Reach Sexual Maturity Younger and Younger
The phase between being physically but not socially adult is getting longer.

When Cell Fishing Games Go Wrong
Trial-and-error "fishing" for DNA in the nucleus may be the most important cause of female infertility.

A Sticky Egg Captures The Sperm
A sugar molecule makes the outer coat of a human egg 'sticky', which is vital for enabling the sperm and egg to bind together.

At Last, Reason Why Stress Damages DNA
Adreneline produced by chronic stress, degrades the protein p53 which is considered a tumor suppressor protein and "guardian of the genome."

August 22, 2011--------News Archive

The Basis for Head and Sex Organ Deformities
Data reveals a possible therapy using vitamin B2 to reverse enzyme defects is specific areas of fetal development.

Mother’s BMI Linked to Fatter Babies
Babies of mothers with a higher pre-pregnancy body mass index (BMI) are fatter and have more fat in their liver, a study has found.

Celiac Disease May Explain Some Women's Infertility
A recent study found increased rates of celiac disease in women who present with unexplained infertility.

WHO Child Growth Charts

Toddler, 1954.

Boys are maturing physically earlier than ever before. The age of sexual maturity has been decreasing by about 2.5 months each decade at least since the middle of the 18th century.

Joshua Goldstein, director of the Max Planck Institute for Demographic Research in Rostock (MPIDR), has used mortality data to prove this trend, which until now was difficult to decipher. What had already been established for girls now seems to also be true for boys: the time period during which young people are sexually mature but socially not yet considered adults is expanding.

"The reason for earlier maturity for boys, as with girls, is probably because nutrition and disease environments are getting more favourable for it," says demographer Joshua Goldstein. It has long been documented by medical records that girls are experiencing their first menstruation earlier and earlier.

But comparable data analysis for boys did not exist.

Goldstein resolved this gap by studying demographic data related to mortality. When male hormone production during puberty reaches a maximum level the probability of dying jumps up. This phenomenon, called the "accident hump", exists in almost all societies and is statistically well documented.

Goldstein discovered that the maximum mortality value of the accident hump shifted earlier in age by 2.5 months for each decade since the mid-1700s, or just over two years per century.

Accordingly, the age of boys’ sexual maturity decreased at the same rate. Essentially, the data showed that the age of sexual maturity is getting younger and younger as the accident hump occurrs earlier and earlier. (Research included data for Sweden, Denmark, Norway, Great Britain and Italy. Since 1950 the data is no longer clear but indicates stagnation.)

The maximum of the accident hump occurs in the late phase of puberty, after males reach reproductive capability and their voice changes.

When boys get physically mature they take more risks and the risk of death increases.

The accident hump, which also exists among male apes, occurs because young men participate in particularly risky behaviour when the release of the hormone testosterone reaches its maximum. Dangerous and reckless shows of strength, negligence, and a high propensity to violence lead to an increased number of fatal accidents. The probability remains low, but the rate jumps up considerably (see graphic).

In respect to the developmental stage of the body "being 18 today is like being 22 in 1800" says Joshua Goldstein. He sees the main causes as better nutrition and an improved resilience against diseases. Because the decline began long before the intervention of the automobile (accompanied by a high risk of accident) it appears that the shift in age of maturity is biological, and not related to technological advancements or social activities. When the use of automobiles or guns became common no significant effect on the data could be seen.

Albeit giving evidence for the age shift only indirectly via mortality data, Joshua Goldstein underlines the importance of its biological meaning: "Researchers see for the first time how females and males have been equally responsive to changes in the environment."

The onset of biological versus social adulthood is drifting apart

"The biological and social phases in the lives of young people are drifting apart ever stronger", says Josh Goldstein. "While adolescents become adults earlier in a biological sense, they reach adulthood later regarding their social and economic roles." Life cycle research shows that for more than half a century the age at which people marry, have children, start their careers and become financially independent from their parents continues to rise.

According to Joshua Goldstein, this doesn’t only extend the period of physical adulthood during which young people do not yet have children. "Important decisions in life are being made with an increasing distance from the recklessness of youth."

The demographer points out that it remains unclear whether the "high-risk phase" of adolescence becomes more dangerous for males because it starts earlier. While younger men are less mentally and socially mature, parents also tend to supervise their children more closely when they are younger.

The Max Planck Institute for Demographic Research (MPIDR) in Rostock investigates the structure and dynamics of populations. It focuses on issues of political relevance such as demographic change, aging, fertility, the redistribution of work over the course of life, as well as aspects of evolutionary biology and medicine. The MPIDR is one of the largest demographic research bodies in Europe and one of the worldwide leaders in the field. It is part of the Max Planck Society, the internationally renowned German research society.
www.demogr.mpg.de

Original article: http://www.mpg.de/4397713/sexual_maturity_in_boys?page=2