Tag Archives: University of California Berkeley

University of California Berkeley study: New 3D printer shapes objects with rays of light: The technology has potential to transform how products from prosthetics to eyeglass lenses are designed and manufactured

2 Feb

3D Printer.com describes what a 3D printer is:

3D printing or additive manufacturing is a process of making three dimensional solid objects from a digital file.
The creation of a 3D printed object is achieved using additive processes. In an additive process an object is created by laying down successive layers of material until the object is created. Each of these layers can be seen as a thinly sliced horizontal cross-section of the eventual object.
3D printing is the opposite of subtractive manufacturing which is cutting out / hollowing out a piece of metal or plastic with for instance a milling machine.
3D printing enables you to produce complex (functional) shapes using less material than traditional manufacturing methods….
How Does 3D Printing Work?
It all starts with the creation of a 3D model in your computer. This digital design is for instance a CAD (Computer Aided Design) file. A 3D model is either created from the ground up with 3D modeling software or based on data generated with a 3D scanner. With a 3D scanner you’re able to create a digital copy of an object…. https://3dprinting.com/what-is-3d-printing/

See, What is 3D printing and how does it work https://www.youtube.com/watch?v=Vx0Z6LplaMU

Alek Hidell of Anonymous posted 3D Printed Guns Make Gun Control Debate Obsolete:

That brings up a whole new debate. If you are able to manufacture banned, hard to get or untraceable guns, the entire existing gun debate becomes irrelevant. Who cares about background checks when you can make your AR at home?
Everyone should have seen this coming. Where there is a will, there is a way. The future of 3D printed guns is uncertain, but the conversation is only just beginning. I’m pretty sure that like all other digital information, once its out there, its out there and cannot be turned back. While politicians go around in circles with the current gun debate in the U.S., innovators like Cody Wilson will be there to show the folly in their ways…. http://anonhq.com/3d-printed-guns-make-gun-control-debate-obsolete/

3D printing is another area where technology will have profound impact on society.

Science Daily reported in New 3D printer shapes objects with rays of light: The technology has potential to transform how products from prosthetics to eyeglass lenses are designed and manufactured:

A new 3D printer uses light to transform gooey liquids into complex solid objects in only a matter of minutes.
Nicknamed the “replicator” by the inventors — after the Star Trek device that can materialize any object on demand — the 3D-printer can create objects that are smoother, more flexible and more complex than what is possible with traditional 3D-printers. It can also encase an already existing object with new materials — for instance, adding a handle to a metal screwdriver shaft — which current printers struggle to do.
The technology has the potential to transform how products from prosthetics to eyeglass lenses are designed and manufactured, the researchers say.
“I think this is a route to being able to mass-customize objects even more, whether they are prosthetics or running shoes,” said Hayden Taylor, assistant professor of mechanical engineering at the University of California, Berkeley, and senior author of a paper describing the printer, which appears online today (Jan. 31) in the journal Science.
“The fact that you could take a metallic component or something from another manufacturing process and add on customizable geometry, I think that may change the way products are designed,” Taylor said.
Most 3D printers, including other light-based techniques, build up 3D objects layer by layer. This leads to a “stair-step” effect along the edges. They also have difficulties creating flexible objects because bendable materials could deform during the printing process, and supports are required to print objects of certain shapes, like arches.
The new printer relies on a viscous liquid that reacts to form a solid when exposed to a certain threshold of light. Projecting carefully crafted patterns of light — essentially “movies” — onto a rotating cylinder of liquid solidifies the desired shape “all at once.”
“Basically, you’ve got an off-the-shelf video projector, which I literally brought in from home, and then you plug it into a laptop and use it to project a series of computed images, while a motor turns a cylinder that has a 3D-printing resin in it,” Taylor said. “Obviously there are a lot of subtleties to it — how you formulate the resin, and, above all, how you compute the images that are going to be projected, but the barrier to creating a very simple version of this tool is not that high.”
Taylor and the team used the printer to create a series of objects, from a tiny model of Rodin’s “The Thinker” statue to a customized jawbone model. Currently, they can make objects up to four inches in diameter.
“This is the first case where we don’t need to build up custom 3D parts layer by layer,” said Brett Kelly, co-first author on the paper who completed the work while a graduate student working jointly at UC Berkeley and Lawrence Livermore National Laboratory. “It makes 3D printing truly three-dimensional….” https://www.sciencedaily.com/releases/2019/01/190131143330.htm

Citation:

New 3D printer shapes objects with rays of light
The technology has potential to transform how products from prosthetics to eyeglass lenses are designed and manufactured
Date: January 31, 2019
Source: University of California – Berkeley
Summary:
A new 3D printer uses light to transform gooey liquids into complex solid objects in only a matter of minutes. The printer can create objects that are smoother, more flexible and more complex than what is possible with traditional 3D-printers. It can also encase an already existing object with new materials, which current printers struggle to do.

Journal Reference:
Brett E. Kelly, Indrasen Bhattacharya, Hossein Heidari, Maxim Shusteff, Christopher M. Spadaccini, Hayden K. Taylor. Volumetric additive manufacturing via tomographic reconstruction. Science, 2019 DOI: 10.1126/science.aau7114

Here is the press release from UC Berkeley:

New 3D printer uses rays of light to shape objects, transform product design
By Kara Manke| January 31, 2019
A new 3D printer uses light to transform gooey liquids into complex solid objects in only a matter of minutes.
Nicknamed the “replicator” by the inventors — after the Star Trek device that can materialize any object on demand — the 3D printer can create objects that are smoother, more flexible and more complex than what is possible with traditional 3D printers. It can also encase an already existing object with new materials — for instance, adding a handle to a metal screwdriver shaft — which current printers struggle to do.
The technology has the potential to transform how products from prosthetics to eyeglass lenses are designed and manufactured, the researchers say.
“I think this is a route to being able to mass-customize objects even more, whether they are prosthetics or running shoes,” said Hayden Taylor, assistant professor of mechanical engineering at UC Berkeley and senior author of a paper describing the printer, which appears online today (Jan. 31) in the journal Science.
“The fact that you could take a metallic component or something from another manufacturing process and add on customizable geometry, I think that may change the way products are designed,” Taylor said.
Most 3D printers, including other light-based techniques, build up 3D objects layer by layer. This leads to a “stair-step” effect along the edges. They also have difficulties creating flexible objects because bendable materials could deform during the printing process, and supports are required to print objects of certain shapes, like arches.
The new printer relies on a viscous liquid that reacts to form a solid when exposed to a certain threshold of light. Projecting carefully crafted patterns of light — essentially “movies” — onto a rotating cylinder of liquid solidifies the desired shape “all at once.”
“Basically, you’ve got an off-the-shelf video projector, which I literally brought in from home, and then you plug it into a laptop and use it to project a series of computed images, while a motor turns a cylinder that has a 3D printing resin in it,” Taylor said. “Obviously there are a lot of subtleties to it — how you formulate the resin, and, above all, how you compute the images that are going to be projected, but the barrier to creating a very simple version of this tool is not that high.”
Taylor and the team used the printer to create a series of objects, from a tiny model of Rodin’s “The Thinker” statue to a customized jawbone model. Currently, they can make objects up to four inches in diameter.
“This is the first case where we don’t need to build up custom 3D parts layer by layer,” said Brett Kelly, co-first author on the paper who completed the work while a graduate student working jointly at UC Berkeley and Lawrence Livermore National Laboratory. “It makes 3D printing truly three-dimensional.”
The new printer was inspired by the computed tomography (CT) scans that can help doctors locate tumors and fractures within the body.
CT scans project X-rays or other types of electromagnetic radiation into the body from all different angles. Analyzing the patterns of transmitted energy reveals the geometry of the object.
“Essentially we reversed that principle,” Taylor said. “We are trying to create an object rather than measure an object, but actually a lot of the underlying theory that enables us to do this can be translated from the theory that underlies computed tomography.”
Besides patterning the light, which requires complex calculations to get the exact shapes and intensities right, the other major challenge faced by the researchers was how to formulate a material that stays liquid when exposed to a little bit of light, but reacts to form a solid when exposed to a lot of light.
“The liquid that you don’t want to cure is certainly having rays of light pass through it, so there needs to be a threshold of light exposure for this transition from liquid to solid,” Taylor said.
The 3D printing resin is composed of liquid polymers mixed with photosensitive molecules and dissolved oxygen. Light activates the photosensitive compound which depletes the oxygen. Only in those 3D regions where all the oxygen has been used up do the polymers form the “cross-links” that transform the resin from a liquid to a solid. Unused resin can be recycled by heating it up in an oxygen atmosphere, Taylor said.
“Our technique generates almost no material waste and the uncured material is 100 percent reusable,” said Hossein Heidari, a graduate student in Taylor’s lab at UC Berkeley and co-first author of the work. “This is another advantage that comes with support-free 3D printing.”
The objects also don’t have to be transparent. The researchers printed objects that appear to be opaque using a dye that transmits light at the curing wavelength but absorbs most other wavelengths.
“This is particularly satisfying for me, because it creates a new framework of volumetric or ‘all-at-once’ 3D printing that we have begun to establish over the recent years,” said Maxim Shusteff, a staff engineer at the Livermore lab. “We hope this will open the way for many other researchers to explore this exciting technology area.”
Indrasen Bhattacharya of UC Berkeley is co-first author of the work. Other authors include Christopher M. Spadaccini of Lawrence Livermore National Laboratory.
This work was supported by UC Berkeley faculty startup funds and by Laboratory-Directed Research and Development funds from Lawrence Livermore National Laboratory. The team has filed a patent application on the technique.
RELATED INFORMATION
• Volumetric additive manufacturing via tomographic reconstruction (Science)
• Taylor lab website
https://news.berkeley.edu/2019/01/31/new-3d-printer-uses-rays-of-light-to-shape-objects-transform-product-design/
If a person is intent on harm, there are a variety of methods. Table 20 of the Uniform Crime Report provides those statistics. http://www.fbi.gov/about-us/cjis/ucr/crime-in-the-u.s/2011/crime-in-the-u.s.-2011/tables/table-20

Guns are not the only instruments of harm.

Evie Blad reported in the Education Week article, School Stabbings Signal Need for Broad Safety Plans: Experts question hyperfocus on guns:

Large-scale shootings have been a dominant driver of school safety debates, but a stabbing spree at a Pennsylvania high school this month should serve as a reminder that educators need to be prepared for a range of situations—including smaller, nonfatal incidents that don’t involve guns at all, school safety experts say.
Following most school shootings—like the December 2012 killings at Sandy Hook Elementary School in Newtown, Conn.—conversation quickly turns to the polarizing subject of gun policy.
And while some districts work to implement comprehensive safety plans that address mental-health concerns, school climate, and security procedures, policymakers often direct efforts and resources specifically toward the prevention of gun-related incidents, experts say.
“When we focus our policy responses almost entirely on firearms in these events, we overlook major things and we aren’t going to address the root of the problem,” said Laura E. Agnich, an assistant professor of criminal justice and criminology at Georgia Southern University in Statesboro.
That narrow focus can lead to “knee jerk” responses such as overly broad zero-tolerance policies and costly building upgrades, instead of research-based school climate measures and carefully practiced safety procedures, Ms. Agnich said.
In the 2010-11 school year, U.S. public schools reported 5,000 cases of student possession of a firearm or explosive device, and 72,300 cases of possession of a knife or other sharp object, according to the most recent information available from the U.S. Department of Education…. http://www.edweek.org/ew/articles/2014/04/23/29knives_ep.h33.html

NI Direct of Northern Ireland has some great information for parents about knife crimes.

In the article, Keeping your child safe from knife crime, NI Direct advises:

Know the law
Before talking to your child about knives, you need to know the facts:
• it is illegal for anyone to carry a knife if they intend to use it as a weapon – even in self defence
• police can search anyone they suspect of carrying a knife
• carrying a knife could mean being arrested, going to court and getting a criminal record, or even a prison sentence
• Knives, offensive weapons and the law (crime, justice and the law section)
Knives in school
It is a criminal offence to have a knife or other weapon on school premises. If a knife or other weapon is found on a pupil, the police will be called and it is likely the pupil will be arrested.
• School attendance and absence: the law
• If your child is arrested and charged
Talking to your child about knives
The best way to stop your child getting involved with knives is to talk to them about the dangers. This may not be easy as they may not want to talk about it, but keep trying as this is the first step to keeping your child safe.
You should remind them that by carrying a knife they are:
• giving themselves a false sense of security
• potentially arming an attacker, increasing the risk of getting stabbed or injured
• breaking the law
Keep a look out
Sometimes there might be obvious reasons for you to think your child is carrying a knife – such as a knife going missing from the kitchen.
However, there are other more subtle signs that you and the parents of your child’s friends can look out for such as:
• school’s not going well or they don’t want to go in to school at all
• they’ve been a recent victim of theft/bullying/mugging
• a different network of friends who may be older than your child…
http://www.nidirect.gov.uk/keeping-your-child-safe-from-knife-crime

The American Knife and Tool Institute (AKTI) has a great discussion about the laws governing knives. https://www.akti.org/legislation/guide-understanding-knife-laws-america

School violence is a complex set of issues and there is no one solution. The school violence issue mirrors the issue of violence in the larger society. Trying to decrease violence requires a long-term and sustained focus from parents, schools, law enforcement, and social service agencies.

Resources:

A Dozen Things Students Can Do to Stop School Violence http://www.sacsheriff.com/crime_prevention/documents/school_safety_04.cfm

A Dozen Things. Teachers Can Do To Stop School Violence
http://www.ncpc.org/cms-upload/ncpc/File/teacher12.pdf

Preventing School Violence: A Practical Guide
http://www.indiana.edu/~safeschl/psv.pdf

Related:

Violence against teachers is becoming a bigger issue https://drwilda.com/2013/11/29/violence-against-teachers-is-becoming-a-bigger-issue/

Hazing remains a part of school culture
https://drwilda.com/2013/10/09/hazing-remains-a-part-of-school-culture/

FEMA issues Guide for Developing High-Quality School Emergency Operations Plans
https://drwilda.com/2013/07/08/fema-issues-guide-for-developing-high-quality-school-emergency-operations-plans/

Study: 1 in 3 teens are victims of dating violence
https://drwilda.com/2013/08/05/study-1-in-3-teens-are-victims-of-dating-violence/

Pediatrics article: Sexual abuse prevalent in teen population
https://drwilda.com/2013/10/10/pediatrics-article-sexual-abuse-prevalent-in-teen-population/

Where information leads to Hope. © Dr. Wilda.com

Dr. Wilda says this about that ©

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COMMENTS FROM AN OLD FART©
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Dr. Wilda Reviews ©
http://drwildareviews.wordpress.com/

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https://drwilda.com/

University of California Berkeley study: Chemicals used in personal care products linked to early puberty in girls

23 Dec

The goal of this society should be to raise healthy and happy children who will grow into concerned and involved adults who care about their fellow citizens and environment. Science Daily reported in Prenatal exposure to common household chemicals linked with substantial drop in child IQ:

Children exposed during pregnancy to elevated levels of two common chemicals found in the home–di-n-butyl phthalate (DnBP) and di-isobutyl phthalate (DiBP)–had an IQ score, on average, more than six points lower than children exposed at lower levels, according to researchers at Columbia University’s Mailman School of Public Health. The study is the first to report a link between prenatal exposure to phthalates and IQ in school-age children. Results appear online in the journal PLOS ONE.
PSYBLOG lists common household items in 8 Household Items Newly Found to Lower Children’s IQ Significantly:
Avoiding phthalates
While it is impossible to avoid phthalates completely, they are found in these common products, amongst others:
• Hairspray.
• Plastic containers used for microwaving food.
• Lipstick.
• Air fresheners.
• Dryer sheets.
• Nail polish.
• Some soaps.
• Recycled plastics labelled 3,6 or 7.
http://www.spring.org.uk/2014/12/8-household-items-newly-found-to-lower-childrens-iq-significantly.php

A University of California Berkeley study found chemicals in personal care products could be linked to early puberty in girls.

Healio reported in Chemicals used in personal care products linked to early puberty in girls:

Prenatal exposure to chemicals found in toothpaste, fragrances and makeup may cause girls to enter puberty at an earlier age, according to a study published in Human Reproduction….
“We also found that girls who had higher levels of parabens (used as preservatives in makeup and other personal care products) in their urine at age 9 also entered puberty about 6 months earlier than those with lower levels.”
Harley and colleagues used data from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) — a longitudinal birth cohort study of pesticides and other environmental exposures among children in a farmworker community — to follow 338 children (179 girls) from birth to adolescence. Pregnant women were enrolled in CHAMACOS between 1999 and 2000, and most were Latina, living below the federal poverty line and had not graduated from high school. The researchers measured concentrations of chemicals in urine collected from the mothers during pregnancy and children aged 9 years.
Harley and colleagues used Tanner staging to measure pubertal timing among the children every 9 months between the ages of 9 and 13 years.
The researchers noted an association between earlier onset of pubic hair development in girls and prenatal urinary monoethyl phthalate concentrations, and earlier menarche and prenatal triclosan and 2.4-dichlorophenol concentrations. Methyl paraben was associated with earlier breast and pubic hair development and menarche; probyl paraben was associated with earlier menarche; and 2.5 dichlorophenol was associated with later pubic hair development.
The researchers found no associations between prenatal urinary biomarker concentrations and the early onset of puberty in boys, and only one association with peripubertal concentrations: propyl paraben was linked to earlier genital development.
The study results are “important because earlier puberty in girls is associated with an increased risk for mental health and behavior problems in childhood and increased risk for breast cancer later in life,” Harley said. “These chemicals are suspected endocrine disruptors and appear to act as weak estrogens in some circumstances, which may explain why we found the associations in girls but not boys…. https://www.healio.com/pediatrics/endocrinology/news/online/%7B85201e95-39e6-4ff1-a642-9806d8c4cac9%7D/chemicals-used-in-personal-care-products-linked-to-early-puberty-in-girls

Citation:

Harley KG, Berger KP, Kogut K, et al. Association of phthalates, parabens and phenols found in personal care products with pubertal timing in girls and boys [published online December 4, 2018]. Hum Reprod. doi:10.1093/humrep/dey337

Here is the press release from University of California Berkeley:

Prenatal exposure to chemicals in personal care products may speed puberty in girls
By Kara Manke| December 3, 2018
Many personal care products contain chemicals that are known endocrine-disruptors. A new study shows that prenatal exposure to two common chemicals, diethyl phosphate and triclosan, may be linked to earlier puberty in girls.
Girls exposed to chemicals commonly found in toothpaste, makeup, soap and other personal care products before birth may hit puberty earlier, according to a new longitudinal study led by researchers at UC Berkeley.
The results, which were published Dec. 4 in the journal Human Reproduction, came from data collected as part of the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study, which followed 338 children from before birth to adolescence to document how early environmental exposures affect childhood development.
Over the past 20 years, studies have shown that girls and possibly boys have been experiencing puberty at progressively younger ages. This is troubling news, as earlier age at puberty has been linked with increased risk of mental illness, breast and ovarian cancer in girls and testicular cancer in boys.
Researchers in the School of Public Health found that daughters of mothers who had higher levels of diethyl phthalate and triclosan in their bodies during pregnancy experienced puberty at younger ages. The same trend was not observed in boys.
Diethyl phthalate is often used as a stabilizer in fragrances and cosmetics. The antimicrobial agent triclosan — which the FDA banned from use in hand soap in 2017 because it was shown to be ineffective — is still used in some toothpastes.
“We know that some of the things we put on our bodies are getting into our bodies, either because they pass through the skin or we breathe them in or we inadvertently ingest them,” said Kim Harley, an associate adjunct professor in the School of Public Health. “We need to know how these chemicals are affecting our health.”
Researchers suspect that many chemicals in personal care products can interfere with natural hormones in our bodies, and studies have shown that exposure to these chemicals can alter reproductive development in rats. Chemicals that have been implicated include phthalates, which are often found in scented products like perfumes, soaps and shampoos; parabens, which are used as preservatives in cosmetics; and phenols, which include triclosan.
However, few studies have looked at how these chemicals might affect the growth of human children. “We wanted to know what effect exposure to these chemicals has during certain critical windows of development, which include before birth and during puberty,” Harley said.
The CHAMACOS study recruited pregnant women living in the farm-working, primarily Latino communities of Central California’s Salinas Valley between 1999 and 2000. While the primary aim of the study was to examine the impact of pesticide exposure on childhood development, the researchers used the opportunity to examine the effects of other chemicals as well.
The team measured concentrations of phthalates, parabens and phenols in urine samples taken from mothers twice during pregnancy, and from children at the age of 9. They then followed the growth of the children — 159 boys and 179 girls — between the ages of 9 and 13 to track the timing of developmental milestones marking different stages of puberty.
The vast majority — more than 90 percent — of urine samples of both mothers and children showed detectable concentrations of all three classes of chemicals, with the exception of triclosan which was present in approximately 70 percent of samples.
The researchers found that every time the concentrations of diethyl phthalate and triclosan in the mother’s urine doubled, the timing of developmental milestones in girls shifted approximately one month earlier. Girls who had higher concentrations of parabens in their urine at age 9 also experienced puberty at younger ages. However, it is unclear if the chemicals were causing the shift, or if girls who reached puberty earlier were more likely to start using personal care products at younger ages, Harley said.
“While more research is needed, people should be aware that there are chemicals in personal care products that may be disrupting the hormones in our bodies,” Harley said.
Consumers who are concerned about chemicals in personal care products can take practical steps to limit their exposure, Harley said.
“There has been increasing awareness of chemicals in personal care products and consumer demand for products with lower levels of chemicals,” Harley said. “Resources like the Environmental Working Group’s Skin Deep database or the Think Dirty App can help savvy consumers reduce their exposure.”
Co-authors include Kimberly P. Berger, Katherine Kogut, Kimberly Parra and Brenda Eskenazi of UC Berkeley’s School of Public Health; Robert H. Lustig of the Department of Pediatrics at the University of California, San Francisco; Louise C. Greenspan of the Department of Pediatrics at Kaiser Permanente; and Antonia M. Calafat and Xiaoyun Ye of the National Center for Environmental Health, Centers for Disease Control and Prevention.
This research was supported by the National Institute of Environmental Health Sciences (NIEHS) grants R21 ES024909, P01 ES009605, R01 ES017054, RC2 ES018792, R01 ES021369, and R24 ES028529 and the US Environmental Protection Agency (USEPA) grants R82670901, RD83171001, and RD83451301.
RELATED INFORMATION
Association of phthalates, parabens and phenols found in personal care products with pubertal timing in boys and girls (Human Reproduction)
CHAMACOS study website

Saundra Young of CNN wrote about toxic chemicals in ‘Putting the next generation of brains in danger.’

According to Young there are several types of chemicals which pose a danger:

The best example of this, he said, is cosmetics and phthalates. Phthalates are a group of chemicals used in hundreds of products from cosmetics, perfume, hair spray, soap and shampoos to plastic and vinyl toys, shower curtains, miniblinds, food containers and plastic wrap.
You can also find them in plastic plumbing pipes, medical tubing and fluid bags, vinyl flooring and other building materials. They are used to soften and increase the flexibility of plastic and vinyl.
In Europe, cosmetics don’t contain phthalates, but here in the United States some do.
Phthalates previously were used in pacifiers, soft rattles and teethers. But in 1999, after a push from the U.S. Consumer Product Safety Commission, American companies stopped using them in those products.
“We certainly have the capability, it’s a matter of political will,” Landrigan said. “We have tried in this country over the last decade to pass chemical safety legislation but the chemical industry and their supporters have successfully beat back the effort.”
However, the Food and Drug Administration said two of the most common phthalates, — dibutylphthalate, or DBP, used as a plasticizer in products such as nail polishes to reduce cracking by making them less brittle, and dimethylphthalate, or DMP used in hairsprays — are now rarely used in this country.
Diethylphthalate, or DEP, used in fragrances, is the only phthalate still used in cosmetics, the FDA said.
“It’s not clear what effect, if any, phthalates have on human health,” according to the FDA’s website. “An expert panel convened from 1998 to 2000 by the National Toxicology Program (NTP), part of the National Institute for Environmental Safety and Health, concluded that reproductive risks from exposure to phthalates were minimal to negligible in most cases….” http://www.cnn.com/2014/02/14/health/chemicals-children-brains/

See, Helping to protect children from the harmful effects of chemicals http://www.who.int/ipcs/highlights/children_chemicals/en/

Children will have the most success in school, if they are ready to learn. Ready to learn includes proper nutrition for a healthy body and the optimum situation for children is a healthy family. Many of societies’ problems would be lessened if the goal was a healthy child in a healthy family.

Our goal as a society should be a healthy child in a healthy family who attends a healthy school in a healthy neighborhood. ©

Where information leads to Hope. © Dr. Wilda.com

Dr. Wilda says this about that ©

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