Science 

Communication


 I am interested in open science and passionate about making science & technology accessible to as many people as possible. I use photography as a medium to engage people in scientific themes.

 

Book Review: Mama’s Last Hug: Animal Emotions and What They Tell us about Ourselves by Frans de Waal published in Natural Selections Magazine: http://selections.rockefeller.edu/review-mamas-last-hug-animal-emotions-and-what-they-tell-us-about-ourselves/?fbclid=IwAR0OH0AWvMuQddHS6mLhvTEYoh8vr9iq--RLf2ZFLPaaQz2QxwhYzykKdL0.


Public talk about Faces & Facial Expressions at The Science is Everywhere Festival with Biobus & RockEDU as part of the Brain Awareness week 2021 ( in Spanish / en Españolhttps://www.youtube.com/watch?v=hOpIPzwVJfY 



WHAT MAKES YOU MOVE? for the Incubator Blog at RockEDU SCIENCE OUTREACH:

 https://rockedu.rockefeller.edu/blog/what-makes-you-move/

DOUBLE HELIX IN THE SKY

 


Double helix, is a term used to describe the physical structure of DNA. The deoxyribonucleic acid or DNA is a molecule that stores our genetic instructions, i.e. the information that programs all of our cell’s activities. It is a letter code providing the instructions for everything  you are. And it does the same for every other living thing. If you are a human, every one of your somatic cells has 46 chromosomes each containing one big DNA molecule.  These chromosomes are packed together  tightly with proteins in the nucleus of the cell.


A DNA molecule is made up of two linked strands that wind around each other to resemble a twisted ladder in a helix-like shape. Each strand has a backbone made of alternating sugar (deoxyribose) and phosphate groups. Attached to each sugar is one of four bases: adenine (A), cytosine (C), guanine (G) or thymine (T). The two strands are connected by chemical bonds between the bases: adenine bonds with thymine, and cytosine bonds with guanine.

The DNA's double-helical structure was discovered in 1950s. Knowledge about the structure, involving two complementary strands of DNA,  each providing the template for making the other strand, provided a key insight about how DNA serves as the information molecule of all living systems. The double-helix model of DNA structure was published in the journal Nature by James Watson and Francis Crick in 1953, and it was based on the work of Rosalind Franklin, and her student Raymond Gosling, who took the X-ray diffraction imagine of DNA labeled Photo 51, and Maurice Wilkins, Alexander Stokes and Herbert Wilson, and base pairing chemical and biochemical information by Erwin Chargaff. The prior model was  a triple-stranded DNA. Watson, Crick and Wilkins received the Nobel Prize in Physiology or Medicine for their contributions to the discovery.

Sources: NIH National Human Genome Research Institute; Molecular Biology of the Cell, Bruce Alberts, et.al.; “DNA structure and replication @ Crash Course Biology #110.

ABOUT AUTISM SPECTRUM DISORDER (ASD)


Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder, present in childhood, involving distinct human deficits or difficulties around social communication and repetitive behaviors. Not every autistic human shares the same difficulties. However, some  of the overlapping difficulties involve:


a)     Social emotional reciprocity i.e. how you share your social world.

b)  Repetitive behaviors of interest and routines, as well as repetitive motor behaviors.

c)      An infrequent or inappropriate use of gestures.

d)     Challenges in social interactions and relationships.


 

Other difficulties involve high sensitivity to sounds, light, touch, smell or taste. As well as a lack of sensory reactions to pain, temperature or sounds. Although, all of these features are diagnostic, individuals under the ASD umbrella often represent a wide range of severity and often co-occurring signs and symptoms that can include anxiety, depression, sleep disturbance, epilepsy, or savant skills e.g.  obsessive preoccupation with, and memorization of music, maps, historical facts, etc.


 

Until 2019, according to the statistics, ~ 2.7-3.6% of the American population has been found with an autism diagnosis. Unfortunately, the estimate has been rising over time. Although, ASD ranks at the top of the neuropsychiatric disorders with regard to its relative genetic contribution and variety of clinical manifestations, we still don’t have clear diagnostic biomarkers for it. One of the first successful efforts at isolating true ASD risk genes involved the identification of  mutations in Nlg3 and Nlg4 genes. These genes belong to a phylogenetically conserved family of adhesion proteins located in the post-synapsis. Impaired function of Nlg3 and Nlg4 genes is associated with ASD in humans, and impaired social behavior in mice. Nowadays,  there is  enough evidence to support the association of about a dozen copy number variant (CNV)* loci and more than 100 genes involved in ASD, with this list growing.


 

The fact that ASD involves very different human features, poses a challenge for the interpretation of results coming from evolutionarily distinct experimental models e.g. mice. For this reason, in addition to the progress in gene discovery, there have been huge efforts to encourage what is known as the “convergence neuroscience research approach”, which involve the intersection among molecular-level, cellular level and circuit level functions across multiple ASD risk genes. This approach has revealed among others that:

1) Developing excitatory neurons in the human cortex differ substantially between ASD and control subjects. In ASD subjects the excitatory neurons in the developing frontal & parietal cortices contain high expression of ASD genes during early mid-gestation.

2) ASD genetic risk may cause disruptions in the neurogenesis of the cortex by disrupting the connectivity of the network within the cortical layers.

3) ASD risk genes are differentially enriched in distinct cell types of the human brain. For example, post-mortem ASD human cortex reveals an increase in the representation of excitatory neurons and microglia in comparison to control brains.

 


In the last few years,  there has been a global phenomenon of increasing autism prevalence. It is not clear  what is changing in the developing brains to make autism more common. Early diagnosis contributes to improving the cognitive skills of the ASD population. Thus, there has been tremendous efforts to generate  biomarkers that allow for a quick and accurate diagnosis. Some of these efforts involves deep learning algorithms trained to detect  particularities at the level of  behavior e.g.  eye movements &  facial gestures, brain imaging & circuits, as well as genetic profiles. Other strategies involve novel gene therapies like gene replacement, editing, and antisense sense oligonucleotide strategies.

 


Early diagnosis in combination with cognitive and behavioral therapies are fundamental for improving the cognitive skills and life quality of the ASD population. More work needs to be done in order to guarantee access to early diagnosis regardless of race, gender or social status. It turns out to be fundamental to reflect about how  the ASD population perceive the world, what their needs are  and how we can adapt our environment and social construction for them.


 

*Copy number variation (CNV) is a phenomenon in which sections of the genome are repeated and the number of repeats in the genome varies between individuals.


Sources:

1) Willsey H.R. et.al (2022), Genomics convergent neuroscience and progress in understanding autism spectrum disorder, Nature Reviews Neuroscience, 323-341.

2) Autism by the numbers (2021), Spectrum’s Guide to Prevalence Estimates, Spectrum, Simons Foundation.

3)https://autismwales.org/en/community-services/i-work-with-children-in-health-social-care/the-birthday-party/

4)     Embracing Autism, A little help for Our Friends Podcast

5)     https://www.spectrumnews.org/

6)    Corthals, et. al., (2017) Neuroligins Nlg2 and Nlg4 affect social behavior in Drosophila Melanogaster, Frontiers in Psychiatry, 1-13.

OCÉANO PLÁSTICO / PLASTIC OCEAN


"El Plástico – es  una increíble invención y una tortura para nuestro planeta. Cerca de 300 millones de toneladas de plástico son producidas cada año. La mayoría de este plástico nunca será reciclado y permanecerá en nuestra tierra y en nuestros océanos para siempre. Nuestra historia muestra el daño que el plástico ocasiona a todos los seres vivos cuya comida depende del océano - de los  pájaros... para nosotros. "


"Plastic - both a wonderful invention and a scourge on our planet. Over 300 million tons will be produced this year. Most is never recycled and remains on our land and in our seas forever. Our story shows the damage to all creatures who depend on the ocean for their food – from birds… to us."



Océano plástico es un video producido por la Organización de las Naciones Unidas (ONU), originalmante en el  idioma inglés. El video ha sido doblado al español utilizando Free-Speech AI -un asistente de doblaje que utiliza inteligencia artificial. https://freespeechnow.ai/


Plastic Ocean is a video originally produced by the United Nations: https://www.youtube.com/watch?v=ju_2NuK5O-E. The video was translated from english to spanish using the Free-Speech AI powered assistant.  https://freespeechnow.ai/

AUTUMN LEAVES


Fall is probably my favorite season. The autumn light is particularly beautiful and the display of leaves switching from green to yellow, orange, red, or eventually brown makes me think of the beauty of the seasons and changes.

 

The change in the color of the leaves and their falling is mainly dictated by the calendar.  As the nights grow longer and cooler, a series of biochemical processes in the leaf start to paint the hues of fall. When the trees sense from the environment the cold and shortness of the days, they signal a cascade of biochemical events to start their downbeat for the winter. These signals start to degrade the chlorophyll , the green pigment , that allows the trees to absorb energy from light,  and also makes them green.  Once the chlorophyll starts to degrade, other pigments that have always been in the leaf start to display,  and that is how you get yellows, oranges and sometimes browns. Thus,  autumn colors are given by other non- chlorophyll pigments. The pigments responsible for the autumn palette are:


 


But,  why would the trees spend energy producing reds for leaves that will fall into the ground? Some scientists think these pigments act as a sunscreen or a deterrent for insects, protecting the leaves as the tree is trying to save as much of the material as possible . In some way the red helps the leaves to hang a bit longer from the tree. Thus, it is a tradeoff,  the tree is using some energy to get the other energy that is present in the leaf back to the tree.  However, this is not a conclusive explanation behind the red pigmentation.

 


After the leaves change color they are ready to separate from the tree and a little bit of  wind or rain will make them fall to the ground. So before all leaves fall into the ground and the winter arrives, go out for a hike and smile at the autumn and its colors.  

 

Sources:

1) https://www.compoundchem.com/2014/09/11/autumnleaves/

2) https://www.fs.usda.gov/visit/fall-colors/science-of-fall-colors