On April 26, 1986, the world saw the worst civilian nuclear disaster in history when Unit 4 of the nuclear power station in Chernobyl, Ukraine, was destroyed. The explosion and subsequent fire released radioactive material into the environment that still lingers today. The Soviet government closed off a 30-kilometer area around the plant, and hundreds of thousands of people were evacuated, never to return home.

Thirty-one years have passed since that fateful day, but scientists continue to study how the levels of radioactivity in the exclusion zone around the city affect local species of flora and fauna. Researchers such as Israel Galván and his colleagues at Paris-Sud University in 2014 studied birds near the Chernobyl nuclear-disaster site and they found evidence of wild birds adapting to ionizing radiation. This type of radiation damages cells causing the production of highly reactive compounds, known as free radicals. A bird can protect itself against free radicals with antioxidants but, if the level of antioxidants is too low, radiation produces oxidative stress and DNA damage, leading to aging and death.

The researchers captured 152 birds representing 16 species from sites within and near the Chernobyl exclusion zone. They took blood samples and analyzed the birds’ levels of antioxidants, how much their DNA had been damaged, and their body condition. They also measured the levels of the pigment pheomelanin (a type of melanin) in the birds’ feathers. Pheomelanin requires many antioxidants; birds that produce more pheomelanins are more susceptible to the effects of ionizing radiation. When the researchers compared birds captured in higher radiation areas with those in lower radiation areas, they found something surprising: birds from the higher radiation zones were generally in better condition and they had higher levels of antioxidants. Of all the bird species, great tits (Parus major) and barn swallows (Hirundo rustica) had the highest pheomelanin concentration in their feathers.

This study is important in order to begin to understand how different species of animals such as birds adapt to radioactivity and better understand the environmental impact of other similar incidents such as the Fukushima disaster in Japan.

By Elia Ku

To visit communities in the state of Yucatan is wonderful. But I don’t mean communities that you visit in touristic way. I refer to rural communities, those that do not exceed 3,000 inhabitants. These types of rural communities you visit in a different way: by getting to know the people.

In these rural places you find very friendly people, those who invite you to drink and eat. They treat you in the best possible way: they make beautiful gifts like offering you the fruits of their gardens, something that is valuable to them. However, be careful not to reject them because that makes them feel bad.

It is interesting to see that in these types of communities, where the situation is precarious and most of the time there are no basic services such as health and education, there are people who may not have many economic resources but who are immensely rich in the soul and with a great heart. These types of people offer you their meal of the day, something that no one else does.

I would like to give an example of the community where I collect data for my Masters. In this community, which is named Xoy, I have found incredible people in all aspects. By spending more time with them you realize that they treat you as if you were a member of their family. They are always attentive and helpful but be careful not to refuse all those attentions they have with you! It’s not allowed.

Every Friday, which is the day I visit the community of Xoy, I return with many fruits such as grapefruit and ears of corn, and sometimes with handmade tortillas and food of the day that they made. And something curious is that when I want to pay them for the product, they evade and reject the money, saying that they give it as a gift. Sometimes you sneakily place money on their kitchen table because it is unfair that they give you what little they have without charging for it.

It is this wealth that I mean when I speak of people “rich in soul;” and not everyone has this wealth of which I speak. That is why when we visit communities we try to know them differently, let us try to know them the way they are. We will in for a big surprise.

On my summer vacation my husband and I and our friends visited Cozumel. It was a very fun trip and we returned to Merida with a new friend, Thomas.

We met Thomas on the beach. He looked very friendly as he greeted everyone around and it was no surprise that we were able to have a quick conversation with him. The truth is that Thomas is an older adult of Canadian origin and the biggest surprise was to know that Thomas was currently living in Merida. We exchanged numbers so that when we returned to Merida we could meet again with him.

I really did not think he would call us but within a week of returning to Merida he contacted us and we invited him to our house. I guess I have always been very curious so I asked how he came to live in Merida and he began to tell his story.

It turns out that Thomas lived in Winnipeg, capital of Manitoba in Canada, and was a train driver. On a vacation in 2016, he visited Ecuador and was on the beach when an earthquake occurred, which filled him with fear and despair. Apparently, he made friends with an Ecuadorian family that invited him to stay at their house in the highlands because there was a Tsunami alert.

Thomas spent a week living with the family, without electricity or water, in a very modest way. At the end of the week he returned to his hotel and tried to give money to the family as a gesture of kindness for their hospitality, but the family flatly refused. I think that from that moment he had a kind of epiphany because he realized that there was more than material life. He came back to Winnipeg and he called his work and he resigned; he sold his properties and part of his belongings and he ventured to a new life in Latin America, I was amused that he searched Google for safe places to live in México and found Merida, Yucatán.

Thomas’s adventure does not end there. It turns out that communicating has been a barrier in his daily life because he does not know much Spanish or our culture. He commented that sometimes it is very exhausting and frustrating to try to explain what you want even to order food for take away. At that time I understood that learning Spanish could be as complicated as learning English is for us and more if you are alone without help.

We have been meeting Thomas for a couple of months and he has told us that it has been a relief to have us as friends because he resorts to us every time he does not know how to express himself in certain situations. He thanks us that we help him improve his Spanish and we thank him for helping us practice our English.

This year it has become quite clear the importance of learning English as a second language both to do science and for everyday life. The advice I can give up to now is to practice every time you have an opportunity because someday you might be like my friend Thomas and live in another country or meet people who do not speak your language and what for you represented an adventure becomes a nightmare.

By Aldo Echeverria

Bird photography is complex. But, as always, there are tricks that can make it easier and more accessible to everyone. The only requirement is you like it. Here are some quick tips that makes bird photography a little easier.

A good pair of binoculars

The first thing you have to do is find birds. You probably will not be able to do it if you don´t have good binoculars. As in everything, there are multiple prices, features, sizes and weights. But to start you don´t need the most expensive, heaviest or most far-reaching.  With 8x magnification and about 40cm in diameter you will have a very good image; the bird will be large and enough light will enter such that the image will not be dark. Also the weight is not excessive. Thus it will be comfortable to carry the binoculars for a long time.

Look for the birds on your site

A bird photography session can´t be done by walking around the house in a neighborhood. If you want to take good pictures, I recommend that you go to a park or nature reserve where you will find many birds. If you have a port nearby it may also be a good idea. Gulls in ports are usually the first birds to pose for the amateur photographer. Gulls do not seem to have much trouble staying close to humans. Also you must know the weather. Surely you know that birds appear or disappear depending on the weather. Thus keep that in mind when planning your trip.

Get a good telephoto lens

Depending on the size of the bird, you will need a telephoto lens of greater or lesser magnification. I recommend not less than a 300mm lens. Today you can buy a 300mm lens at affordable prices. If you have more money you can invest in something bigger like a 600mm lens. One thing to consider is that these lenses are heavy. Sometimes this weight makes it difficult to follow the birds when they move a lot. That will cause distortion in some photos. To avoid this, make sure that the lens has the image stabilizer function.

Finally be patient.

Instead of chasing birds, it is advisable to remain as quiet as possible. Soon the birds will lose their fear and they will get closer. Finally when taking photos it is good to take them at low speeds, smaller than 1/500 seconds. Thus the photos will have a better chance of being sharp. Also a good exercise is to try to focus on the eyes of the bird when you take a photo. Thus the photo will look better and be more visually attractive.

By Ana Carrillo

Escherichia coli is a bacterium that inhabits the intestinal microflora of humans, so it is common to find it in fecal matter. However, there are some strains of E. coli that can be pathogenic and cause harm to humans. One of these strains is Escherichia coli O157: H7. This bacterium belongs to the group of E. coli enterohemorrágicas (EHEC). It produces potent toxins that can cause hemorrhagic colitis (CH), a condition characterized by severe abdominal pains, watery diarrhea with blood and little or no fever. In some cases, CH may lead to hemolytic uremic syndrome (HUS), causing acute renal failure, destruction of red blood cells (hemolysis), and a decrease in platelet count (thrombocytopenia), especially in children.

The main reservoirs of this bacterium are ruminants, especially cattle and sheep that become infected without presenting symptoms. Infection in humans is transmitted by eating food contaminated with E. coli O157: H7, e.g., uncooked meats, unpasteurized ciders, unwashed vegetables or water contaminated with feces. Clinical symptoms usually appear 3 to 5 days after ingestion of the bacteria, starting with watery diarrhea, severe abdominal pain, nausea and vomiting, and after one or two days, watery diarrhea may progress to CH. In most cases the symptoms disappear within a week, with no apparent consequences. However, in 15% of cases complications such as HUS and death can occur. The dose required to produce the clinical manifestations is very low, so the risk of disease is very high.

Since 1982, several outbreaks of diarrhea and CH caused by this pathogen have been reported in various parts of the world, mainly the United States, Europe, Japan, Chile, Argentina, Brazil, Colombia and Venezuela. In Mexico there are many limitations to the serological diagnosis of this strain, so only cases of CH and HUS of unknown origin have been reported.

Pharmacological treatment of diarrhea caused by E. coli O157: H7 is still under discussion. Several articles mention that the use of antibiotics leads to increased development of HUS. The authors concluded that antibiotics cause the destruction of the bacteria but do not act on the toxins it produces. Furthermore, they suggest that when the bacteria die, they suffer great stress releasing a greater amount of toxins in the intestine. On the other hand, administration of antidiarrheal agents such as loperamide is contraindicated as it delays the elimination of the pathogen by increasing the absorption of toxins.

In the event of any bloody diarrhea, it is necessary to see a doctor and determine if it is possible that the diarrhea may be due to E. coli O157: H7. However, test results may be delayed as this strain is sometimes difficult to identify. Generally, feces are sent to laboratories with special equipment for detection, which can take 2 or 3 days. During this time, the bacteria may begin to produce toxins.

To prevent infections with this pathogen it is important to wash your hands well after going to the bathroom or when preparing food. Knives used to cut meat and vegetables should not be mixed. Meat should be cooked at a temperature above 70 ° C to properly destroy the bacterium. Consumption of unpasteurized dairy or cider should be avoided. Contaminated water should not be used to irrigate crops. All vegetables should be properly washed. By following these tips you can certainly avoid an intestinal infection caused by E. coli O157: H7.

For 1300 years in Japan and China a unique fishing technique has been used. This technique consists of using birds to fish, more specifically cormorants (family Phalacrocoracidae). Cormorants use their natural predatory instinct for catching fish.

The first step in this process is capturing the wild birds, after which the training process begins. The training consists in caging the cormorants and keeping close contact with them, giving them food and care as if they were pets. After two weeks these birds will have become accustomed to the human company. After the first three weeks the fishermen tie a hemp rope around the cormorants’ neck. The cormorants swim near the boats and during this period they still depend on humans for food.

Once the cormorants are accustomed to having their neck tied with rope, they are ready to fish. Before dawn each day the boats leave for the rivers with a lamp to attract the fish. When the fish approach the ship, the tied-up cormorants that are swimming begin to catch them. Once the fish is caught, the rope around the neck of the cormorants prevents the fish from being swallowed.

Then the fisherman can take the cormorants back to the boat using the rope. Once in the boat the fisherman causes the cormorant to regurgitate the fish that is in their throat. Although the cormorant cannot eat the larger fish, they are allowed to consume the smaller ones. In this way the fisherman makes sure that his cormorants will keep hunting for fish, since they are still hungry.

Of course, today there are much more efficient methods of fishing. But this type of fishing is maintained to attract tourists and to provide food for people with fewer economic resources. However, the practice of this ancient habit still retains an enigmatic appeal.

Unalaska (or Dutch harbor) is a little fishing town located on Alaska’s coast. This town is 550 km² and has a population of 4.300 people and around 600 bald eagles. In Unalaska, people coexist with eagles in the same way that people in other cities coexist with pigeons. Nevertheless, how has this curios situation arisen?

There are two factors that explain this situation; first, fish are the staple of the bald eagle’s diet, and Unalaska processes more fish than any other port in Alaska. Boats, processors, and garbage create a year-round smorgasbord to which eagles want to nest as close to as possible. The second factor is the Bald Eagle Protection Act of 1940 that protects bald eagles from hunting.

The coexistence is usually peaceful, except during nesting season. Unalaska has a lot of food to support many eagles, but there is not enough space in the small area where the food is to support many nesting pairs. In addition, eagles usually nest in trees, but Unalaska has no trees. Instead, eagles raise chicks on the tundra, cliff outcroppings and buildings. Their nests are a lot more accessible to people, which makes the eagles territorial.

It’s easy to get too close to an eagle nest without even knowing it, which is why local law enforcement puts up warning signs all through the nesting season (from early June to the end of the summer). Even so, Unalaska records between six and ten cases per year in which people require medical attention after encounters with eagles, usually head gashes from talons, which lead to stitches and expensive medical bills. However, most Unalaska people remain good with their raptor neighbors.

The local people say that the sight of so many bald eagles in such a small town is especially impressive for newcomers and travelers. So, if you like to travel and love eagles, Unalaska is an ideal place to visit, but be careful that your visit to the eagles’ city doesn’t end with a stopover in hospital.

Many times I have been told of several masters and doctoral students going into depression. I wondered, but how could that be possible? Well, now I think I know. Students are so full of anxiety because there are not enough hours in the day and night to finish what they need to get done. We know that increasing hours is not possible; only 24 hours are available for any human being, whether you are a child or an adult.

When you are a child you do not realize the course of the hours, they seemingly feel to go by slowly. Now, as an adult, you feel that even going for a drink of water, for example, generates a loss of valuable time. You cannot leave your computer for an instant since that will make the activity that you are doing, whatever it is, be delayed more.

But is the anxiety one feels so much that it can lead to depression? I think that anxiety is just one factor that adds to many others. For example, when doing a job you do not know if you are doing it right or wrong, until the time it is evaluated or presented to an audience. One wants to do well, but on certain occasions that is not a given and that’s when things collapse in front of us, we believe that it is the end of the world, when it’s not so.

But it is precisely this desire to do things perfectly when we know that there is no perfection, the desire to give the maximum of us to the point of collapse, and the excessive number of activities but still believing that we can handle the situation that causes health problems manifested as that disease called depression.

Many get out of depression, many others do not even detect it becoming present in their lives, but many more cannot get out of it. Now I really understand what they wanted to tell me before I entered my Master’s and now I understand why they apply those psychometric tests in the process of selection of postgraduate students, of which they never give us the result.

Could it be that these psychometric tests could indicate how we really were before entering the Postgraduate program? Or will those tests tell us how well we tolerate depression? I think I’ll never know.

With this writing I do not want you to think that I’m about to fall into this horrible disease. Only I want to give my opinion about this latent problem in many students and make it known, because they may think the same thing I did when I was told about this case. Think, how could it be that Postgraduate students go into depression? Well, let me tell you, it does.

It is a regrettable situation that I just raised. One should enjoy the postgraduate process, and I have certainly enjoyed it, but not everything is totally white or totally black and that is precisely what a postgraduate lives: good days and bad days. Those who are victorious at the end of this process will say that EVERYTHING WAS WORTH IT.

Cancer is the second leading cause of death in the world, causing more than 8 million deaths in 2015. Cancer is a disease that can affect people of all ages, including fetuses, and risk increases with age. Generally cancer is caused by abnormalities in the genetic material of the cells. These abnormalities can be caused by genetic inheritance or by different agents such as ultraviolet radiation, chemicals, smoking, and some viruses.

Currently the various cancer treatments are performed in hospitals (surgery, chemotherapy, radiotherapy, transplantation and others). However, these treatments or processes usually occur long after diagnosis, have multiple side effects, and are costly. These latter two factors: side effects and high costs – meaning low-income countries have few treatments – have led to the search for new alternatives to cure cancer. One of these alternatives is based on knowing and studying plants that are used in traditional medicine to “cure cancer”.

One of these plants is the Soursop tree (Annona muricata). This tree is native to Mesoamerica, currently distributed in the tropics of America, Africa and Pacific Islands. Reports from traditional medicine mention that extracts from different parts of the Soursop tree have bactericidal, antiparasitic, and antiviral properties, as well as cytotoxic effects against some types of cancer.

Some Annona muricata compounds such as acetogenins (Annonacin and Uvaricina) have a large cytotoxic effect against some cancer cell lines such as lung cancer. Acetogenins are known to deactivate a cell’s ability to generate ATP by scheduling a programmed cell death in order to control cell development and growth. However, recent studies have linked these compounds with the development of atypical Parkinson. This disease is diagnosed in people who do not respond to conventional treatment to relieve some symptoms of Parkinson’s disease (tremors, stiffness in arms and legs, among others).

Therefore, both compounds continue to be studied to determine their safety in humans and the possible routes of administration in case they can be used for the development of future drugs against cancer. On the other hand it is important to mention that consuming or drinking raw extracts from different parts of the Soursop tree to cure cancer can be dangerous to health. Generally the crude extracts possess a wide range of compounds with some acting in favor and others against. Therefore it is always recommended to carry out pharmacological studies that prove the activity and safety mentioned in traditional medicine.

Photo:

https://www.sanar.org/plantas-medicinales/guanabana-graviola

References:

Click to access S4-MCS24.pdf

http://www.who.int/mediacentre/factsheets/fs297/es/

I grew up with my parents in Mérida and if my memory does not fail, we always had a dog. We never had a cat I think because my mom had the stereotype that these animals are not reliable (they scratch or bite when you least expect it), they are bird killers, their physiological needs stink, they do not feel empathy towards their owner, they are stray, they are carriers of diseases and, in this way, I could continue to make this list of endless evil.

When you grow up with these ideas it is difficult to have a good image of cats as pets. The truth is that I married a man who loves animals and cats are no exception. So, when I least expected it my husband arrived home with a box and a newborn kitten inside. The kitten was in very poor condition; it had an eye infection and it was malnourished. Apparently it was abandoned by people who have no respect towards animals. I did not like the idea of having a cat but in the end I gave in to the insistence of my husband.

We call our cat “Cersei Lannister” (the name of the queen of the famous TV series Game of Thrones) due to the myth that cats believe they are royalty. With the passage of time Cersei recovered her health and began to do cat things.

The first time Cersei licked my foot I thought her tongue had a terrible disease and we had to take her to the vet (you had to have seen the laughter of the vet because of my naivety).  Now, I know that cats have their taste buds in the central part of the tongue, which perform vital physiological functions from combing the fur to removing traces of impurities that may give off odor at the time of hunting.

Observing the behavior of Cersei every day was like seeing a documentary of “National Geographic,” where she was doing things very funny and at the same time strange. If she had food left over from the previous day she did not eat it or the door of the house always had what appeared to be remnants of birds, reptiles, mice, and cockroaches. Also, she would eat the door of my room if I left it closed and had an obsession with kneading while sleeping.

My scientific curiosity was aroused and I began to investigate the behavior of that ball of gray hair and to my surprise it turned out that Cersei was a normal cat. Apparently cats developed a finer sense of smell than humans and can distinguish between good and bad food; what I thought was a whim turned out to be a defense mechanism.

I also discovered that no matter how much food you give your cat they always go hunting because it is in their genes inherited from their ancestors. In turn, the fact that they take their victims to your door is their way of saying that you are part of their family; they are giving you part of the loot. On the other hand, cats are territorial and like to have control of their environment so they hate closed doors. Finally, cats demonstrate their affection towards humans by kneading them with their paws as they did with their mother.

Through Cersei I understood that there is a bad perception of cats and we let ourselves be carried away without giving us even the opportunity to know them. For this reason we must always train ourselves to be critical thinkers, to analyze the opinions or affirmations of everyday life based on valid arguments.

Cersei has been living with me for 4 years. She is a very affectionate cat, intelligent and a very good partner. I do not know if she actually has 9 lives, but at least I know that in one she makes me happy.