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Researchers find explanations behind the mystery of North Pacific gyre

Researchers find explanations behind the mystery of North Pacific gyre

The center of oceans of the Earth are covered with an enormous arrangement of rotating currents known as subtropical gyres, which occupy 40% of the Earth’s surface. They have been considered as stable biological deserts with little deviation in chemical composition or the nutrients needed to sustain life.

The region in the North Pacific Subtropical Gyre ecosystem that occupies the Pacific Ocean between China and the United States has confused scientists over the years by its strange abnormality in chemistry that changes periodically. There is a remarkable variation in the levels of phosphorus and iron which affects the entire nutrient composition and eventually biological productivity.

The research team has found out the explanation behind the variations in the North Pacific Subtropical Gyre ecosystem. It includes Matthew Church, a microbial ecologist with the University of Montana’s Flathead Lake Biological Station, Ricardo Letelier from Oregon State University and David Karl from the University of Hawaii. The work appears in the Proceedings of the National Academy of Sciences.

Church said that the variations in the ocean climate arise to basically control ocean nutrient concentrations by regulating iron supply and altering the kinds of plankton growing in these waters. He also said that after constant, long-term observations on the role of plankton in controlling ocean nutrient availability, their team has finally confirmed that tightly linked plankton supplies nutrients, particularly iron, delivered from the atmosphere.

With the help of three decades of observational data from Station ALOHA, a six-mile area in the Pacific Ocean, the researchers discovered that the periodic shift in the level of iron is due to iron input from Asian dust, accounting for the chemical variances and varying amounts of nutrients to sustain life.

The ocean-atmosphere relationship known as The Pacific Decadal Oscillation varies between weak and strong stages of atmospheric pressure in the northeast Pacific Ocean which is the major factor of the variance. The winds from Asia become stronger and move in a more southern direction in years when the low pressure weakens in the northeast Pacific bringing more dust from Asia and fertilizing the ocean around ALOHA. The opposite occurs when the pressure strengthens.

Phosphorous and iron are the essential components of life and the supply of nutrients is a fundamental controller of ocean productivity. The process of fertilizing the ocean’s upper water level by mixing nutrient-rich water from the bottom is challenging in the North Pacific Subtropical Gyre ecosystem because the waters are very layered and very less mixing takes place. The creatures are allowed to grow and use phosphorus in the upper layers of the ocean when strong Asian winds bring in substantial quantity of iron while they are forced to return to a bottom-water-mixing nutrient delivery system when the Asian winds weaken and iron quantity is reduced creating the periodic ebb and flow of iron and phosphorus levels in the North Pacific Gyre.

Church said that the results from the study highlight the crucial need to include both atmospheric and ocean circulation variability for forecasting the climate change impact on ocean ecosystems. He also added that it confirms the necessity to think about the biology of tightly connected plankton to changes in climate as well as land use which can directly impact dust supply to the ocean.

Researchers hope to see long-term changes in wind patterns across the North Pacific as Earth’s temperature continues to increase. The sources and quantity of iron and other nutrients carried by the wind across the ocean will get affected by the evolution of land use and pollution caused by human activity in Asia.

To know the impact of the changes on ecosystems around the ocean region as well as others around the world, more research is needed.

Journal Reference: Proceedings of the National Academy of Sciences.

Google reveals security flaws in iOS resulted hacking of users personal data

“Security flaws in ios lead to hacking of users personal data”, says Google

Google security researchers said that they have detected several malicious websites which when visited would hack into the iPhone of the visitor without any alert. This is possible by the exploitation of a number of security flaws in the software which were previously not disclosed. 

Google’s Project Zero said that these harmful websites were visited several thousands of times per week by visitors who had no idea of what was going on. Ian Beer, Project Zero’s security researcher said that for the device to be exploited it was enough to visit the malicious website which would then install a monitoring implant if it was successful. The hacking of the iPhones continued for a minimum period of two years.  

Five unique exploit chains were detected that involved a total of twelve separate security flaws. Seven of these flaws involved Safari which is the default browser on iPhones. An attacker managed to get root access( the highest access level) to the iPhone with the help of the other five exploit chains. As a result, all the features could be accessed by the attackers including those which were not accessed even by the users. This helped them in installing applications or other malware in their devices with no knowledge of the users. 

According to an analysis of Google, the personal photos, messages of the users along with their live location could be stolen due to these vulnerabilities. It would also provide access to the saved passwords in the devices. iOS versions 10 to 12 were affected by these vulnerabilities.

They were privately disclosed by Google to Apple in the month of February where it was provided only a week for fixing the flaws and roll out the updates to the users. Since the security flaws were of such a severe nature, very less time period was provided to the developers. After six days, Apple rolled out security patches for iOS 12.1.4 for iPhone 5s, iPad Air and other later models. 

Beer said that it might be possible there are other hacking campaigns which are currently operating. Apple has a good reputation in handling security-related issues. It also increased the bug bounty payment to a maximum of a million dollars if security researchers can detect the flaws which allow the intruders to get root-level access to the device without any interaction from the user side. Under Apple’s new bounty rules — set to go into effect later this year — Google would’ve been eligible for several million dollars in bounties. 

ganymede jupiter

IAU provides opportunity to common people for naming Jupiter’s moons

The largest planet of our solar system, Jupiter has five moons with new name suggestions which are Pandia, Ersa, Eirene, Philophrosyne and Eupheme.

The names were suggested by children who participated in the contest run by Carnegie Institution for Science approved by the International Astronomical Union. Previously the IAU assigned a temporary name to newly found objects before assigning a permanent name but however recently the public has been given a chance to come up with few names for alien stars, planets and craters on Mercury.

The participants at the Jovian contest had to come up with names that were within the character limit and also matched the direction of the moon’s orbit, affecting the final letter of the name.

Carnegie astronomer Scott Sheppard said in a statement that there are many rules for naming moons. Sheppard led the discovery of the 12 moons of Jupiter of which naming of 5 was included in the contest. Jovian naming conventions requires moons to be named after characters from Greek and Roman mythologies who were descendants or consorts of Zeus or Jupiter.

Pandia (previously S/2017 J4) is named after the daughter of Zeus and the moon goddess Selene. Out of many applications, the name got the most attention was from Emma Hugo, representing astronomy club of the Lanivet School in Cornwall, U.K. The institute tweeted a photo of astronomy club with the Pandia sign and school mascot, panda in honor to the role village played in supplying bamboo to London Zoo.

Ersa (previously S/2018 J1) is named after the sister of Pandia, who was another daughter of Zeus and Selene. More than 20 tweets suggested this name but the contribution was credited to Aaron Quah, space news aggregator who sent the suggestion first and Walter, a 4-year-old who sang a song on Ersa.

Eirene (previously S/2003 J5) is recognized as the goddess of peace and is the daughter of Zeus and Themis. Around 16 tweets suggested this name, however, the first tweet came from a user named Quadrupoltensor and a 10-year-old guy who enjoys Greek and Roman Mythology.

Philophrosyne (previously S/2003 J15) is named after the spirit of welcome and kindness, who is the granddaughter of Zeus. Several participants were highlighted including a space fan Lunartic who posted a YouTube video about his suggestions and also suggested a new name for S/2003 J3, Eupheme. It recognizes the spirit of praise and good omen who was the granddaughter of Zeus and sister of Philophrosyne.

Researchers develop practical method for measuring quantum entanglement

Scientists come up with practical method for measurement of quantum entanglement

A team of scientists from Rochester Institute of Technology have created a new method for measuring the quantum entanglement (physical phenomenon that occurs when pairs or groups of particles are generated, interact, or share spatial proximity) that has significant consequences for building the future generation of technology in fields such as computer science, impersonation, safe communication and other areas. The new method for measuring entanglement(complexity) has been summarised by the scientists in a recently published article by Nature Communications journal.

An extraordinary interrelationship was observed in the measurements when two quantum particles like photons, electrons or atom become entangled even if the particles were apart from each other by a large distance. This special quality which can only be described by Quantum Mechanics is the backbone of the various technologies.

Gregory Howland, Assistant Professor and a member of Future Photon Initiative of Rochester Institute of Technology said that Quantum entanglement is a useful resource for performing important activities like quantum computing or secure communication. Also, he said that two people who possess entangled quantum particles can produce an unbreakable key to send messages back and forth to one another in such a way that in case if any third person or party intercepts the message, it will not be possible for them to decipher or decode the message according to laws of physics.

End-user needs to estimate the amount of quantum entanglement present within a given system as quantum technologies have become more sophisticated and complex with every passing day. The new method involving spatially entangled photon pairs needs million-times lesser measurements than the previous methods.

The measurement method has the additional advantage of never over-estimating the amount of entanglement which is present in a system as this method is based on the information theory which studies some of the key factors related to information such as quantification, storage and communication. It has been very crucial for milestone achievements such as compact disc invention, creation of the Internet, Voyager missions.

Howland said that this turns out to be vital because it is not that we are told that we have more of the resource then we actually have and this factor is mainly important for stuff like secure communication to avoid any unwanted interception of a message.

Journal Reference: Nature Communications journal

quantum entanglement

For the first time researchers develop quantum radar based on entangled photons

Quantum revolution has made it possible to sense the world in a different way. The aim is to use the unique properties of quantum mechanics to take measurements or produce images which are otherwise considered impossible. 

Majority of the work is done with the help of photons. However most of the work in quantum revolution involving quantum computing, cryptography has been done with the help of visible or near-visible light. 

However, Shabir Barzanjeh and his team from the Institute of Science and Technology, Austria used entangled microwaves for creating the first quantum radar in the world. It can detect far-away objects with the help of few photons thus demonstrating the stealth radars which can function without emitting detectable electromagnetic radiation. The paper can be found here

A pair of entangled microwave photons are created with the help of a superconducting device known as Josephson parametric converter. The first photon also defined as the signal photon is beamed toward a specific object and then the reflection is captured. In the meantime, the second photon which is also called the idler photon is stored. On the arrival of the reflection, a signature is created by interfering with the idler photon which tells the distance traversed by the signal photon. A normal radar works in the similar manner, however, fails when the power levels involve lesser numbers of microwave photons. Reason being hot objects emit their own microwaves. 

In-room temperature, at any instant, 1000 microwave photons are present which overwhelm the reflecting echo. So powerful transmitters are used by radar systems. This is solved in the entangled photon system. The signal and idler photons help in filtering out the effects of other photons. So it is simple to detect the signal photon upon reflection. Reflection hurts quantum entanglement since it is a fragile property, but the correlation between idler and signal photons help in distinguishing themselves from the noise. 

Researchers said that a room temperature object at a distance of 1 meter was detected with the help of entangled fields using the Josephson parametric converter at millikelvin temperatures. This setup outperforms the normal radar system as it operates with lesser number of photons. But this is only for short distances. 

This experiment shows the application of microwave-based entanglement and quantum radar. A potential demonstration of quantum illumination is also shown. This technique can be used in biomedical applications since it is a non-invasive scanning technique such as human tissue imaging. For a closed environment, there is the obvious application as a stealthy radar that is difficult for adversaries to detect over background noise 

Journal Reference: arxiv

anatomy of brain

Researchers figure out why we remember some incidents for a long time and forget some

It often happens that we can remember something which occurred long back but forget the incident that took place recently. Some memories remain stable while others fade away in minutes.

Researchers from Caltech have found that the memories which remain stable over time are encoded by a group of neurons firing in synchrony thus providing redundancy. The work also tries to understand the effects on memory after tragic events such as brain damage or Alzheimer’s disease.

The experiments were carried out in the laboratory of Carlos Lois, a biology professor and affiliated faculty member of Tianqiao and Chrissy Chen Institute for Neuroscience. It appears in the Science journal.

The team was led by Walter Gonzalez, a postdoc scholar. A test was developed for testing the neural activity of mice when they learn and remember a new place. The mouse was kept in a straight enclosure of length 5 feet. Different symbols were marked in different locations on the walls such as a bold plus sign at the rightmost end and angled slash close to the center. Sugar water was placed at the track ends. As the mouse explored places, the activities of certain neurons in the hippocampus were tracked by the scientists.

When initially placed in the track, the mouse wandered till it found the sugar water. Single neurons were activated when it spotted a symbol on the wall. However, on staying longer, the mouse remembered the sugar locations. As the familiarity increased more neurons got activated in synchrony as it spotted the symbols.

To understand the fading of memories, the mice were kept away from the track for 20 days. On getting back to the track, the mice which had strong memories encoded by high numbers of neurons remembered the task easily. So when large groups of neurons encode an activity, the memories can be easily recalled even if some showed different activity or remained silent.

This can be explained in a way similar to how a long story is remembered. For remembering a long story, it can be told to many different people and when all of them gather each can fill in the gaps which the other member has forgotten. By repeating this every time, the story can be preserved with the strengthening of the memory. In a similar way, neurons help each other in encoding memories which stay over time.

Impairment of memory in any form can affect us a lot since our life is basically driven by memories. Senior citizens get affected by this as a part of the aging process. Alzheimer’s disease also has devastating effects which paralyze even the basic daily functioning of a person. When memory is encoded by fewer neurons it can be forgotten easily. As a result of this, treatments which increase the recruitment of a large number of neurons for encoding a memory help in preventing memory loss.

When an activity is practiced a lot, there are more chances of remembering it as more neurons are encoded for the action. It is usually considered that to make a memory stable, individual connections to a neuron have to be strengthened. However, the study suggests that the memory can be stored for a long period of time with an increase in the neurons which encode it.

Research Paper: Persistence of neuronal representations through time and damage in the hippocampus

We're One Step Closer to a Blood Test that Predicts When a Person Will Die

Researchers are close to blood tests which can estimate mortality risks

In life, there are two inevitable things. Death and taxes. For the first one, scientists have been trying to come up with a test which can help in estimating their mortality. It would check their current health status and then calculate how they might be vulnerable to mortality risk factors. For this purpose, blood tests are most preferred as blood samples can be easily obtained and there are enough labs for handling them. 

This effort is described in a paper which appears in the journal Nature Communications. The team is led by Joris Deelen, a postdoc researcher at the Max Planck Institute for the Biology of Aging and P. Eline Slagboom, molecular epidemiology head, Leiden University Medical Center. Scientists reported that from 44000 healthy patients, an accuracy of 80% in determining mortality risk was achieved through the blood tests. 

Age of the patients varied from 18 to 109 years. They provided their blood samples and their health conditions were tracked till 16 years. A group of 226 metabolites (which are cell and tissue discharges into the blood) were analysed. From this, 14 were chosen which combined with the gender of the person could provide their health risks and possibilities of death in five to ten years. This was done by comparing those who died in the course of study to the ones who did not and separating the elements in the blood which differed significantly. There is a strong correlation between the 14 factors and mortality even after considering factors such as age, sex and death cause. 

Slagboom said that they wanted to account for the vulnerability of the human body which cannot be observed by doctors. Researchers are amazed by the fact that a blood sample at any point of a person’s life can predict the possibilities of any risks in the next five to ten years.

This is not yet ready for application with patients but it provides a solid foundation for future research. A more refined version of the test would be most useful for older patients in helping with their treatment as the 14 metabolites represent processes such as fat and glucose breakdown, body fluid balance which can affect ailments as well as the ability of a person to recover from an injury.

Real-life examples are being studied where researchers are working on chances of recovery of a person undergoing hip surgery and possibilities of side effects such as dementia or delirium after treatment of kidney failure. Scientists are working on large databanks to confirm their results as this only lies the base of the future works. 

Journal Reference: Nature Communications

Large scale structure of light distribution

Scientists conduct experiment to define constraints on the force of dark energy

It is now well established through observations that the universe is expanding which has been speeding up over time. However, the cause of the expansion is not yet known. It is assumed to be a mysterious energy acting opposite to gravity causing this expansion.

This energy is termed as “dark energy” and it is estimated that it makes up to 72 percent of the constituents in the universe. A new experiment has confirmed that it is not a new force. The study appears in the Physical Review Letters journal. Ed Copeland, a physicist from the University of Nottingham said that the experiment related to cosmology and atomic physics helped in ruling out several models which have been proposed for the explanation of dark energy and will eliminate many more models.

There are four fundamental forces in the Universe which are gravity, electromagnetic force, strong nuclear force and weak nuclear force. Some anomalies do not fit into the current model of how the Universe functions. So they are clubbed under a fifth hypothetical force.

These anomalies have helped in putting constraints on the fifth force and helped in constructing alternatives to general relativity for explaining the increasing rate of expansion of the Universe. Some of the alternatives are chameleon theory and symmetron theory.

If another force present in the Universe was responsible for almost 75 percent of its mass-energy density then it should be easy to detect. But if it acts opposite to gravity i.e. a repulsive force then it should be weakest in the area where gravity is the strongest force. This should hold true for objects with significant mass such as a planet.

An experiment was designed to observe this anti-gravitational force. Within a sealed vacuum chamber, a large aluminium sphere and small weights – atoms of rubidium-87 were placed and atom interferometry was used for measuring the acceleration of the smaller weight towards the larger one. If a fifth force was present then the atom should have been veered off its path as it moved towards the sphere. But no such deviation was observed which clearly explains that no such anti-gravity force was present in the chamber. It does not mean that there is no fifth force at all. However, the force can be defined by several constraints which also means that similar constraints can be placed on chameleon and symmetron theories.

There may not be always a straightforward answer to fundamental questions of this nature so the correct questions are asked to narrow down on the correct answer. Answering this question would give significant answers about the evolution of the universe.

Journal Reference: Physical Review Letters

crispr gene art

Scientists create new CRISPR model that allows to edit several genes at once

We have seen several uses of CRISPR gene editing such as accurate cutting and pasting of specific genes in DNA. Scientists have now developed a technique which makes it possible to edit several hundreds of genes at once. This would be very beneficial to the scientists who can reprogram cells in a larger and complex manner thus assisting in the study of genetic disorders. 

CRISPR could mostly edit one gene at a time. As per the latest study, the new technique can hit 25 targets within genes at once. Biochemist Randall Platt, ETH Zurich said that this technique makes it possible to modify entire gene networks in one step which was not even thought in the past. The work has been published in the journal Nature Methods. 

The key to this process is a plasmid, a stabilised RNA structure that can hold and process several RNA molecules. These act as address labels for targeting gene sites. Along with the RNA molecules the plasmid also carries Cas9 enzyme which performs the main cutting and binding job. Cas9 has been mainly used although here Cas12a is used which improves the accuracy of CRISPR editing. Researchers were able to insert this plasmid into human cells in the laboratory. Hence it enables scientists to make gene editing at scale. It can be quite tiring to make a single change at one time as proteins, genes act in complex manners. Operations such as increasing and decreasing the gene activities can be done with greater precision. 

However, this also means that we would be moving in uncharted territories as we do not know the effects of this simultaneous change in the body of the organism. There might be secondary changes which are not expected thus increasing the risk of gene editing. 

Researchers mention that direct repeat sequences and pacers which possess the complementary sequences could create secondary RNA structures which can affect the maturation of the CRISPR RNAs present in the cells. As a result of which, it is essential to consider the complementary regions in pre-CRISPR RNA so as to improve the maturation of CRISPR RNA. Research overcoming these limitations would create several applications for genome engineering. 

CRISPR has been already used in eliminating genes responsible for diseases and killing the superbugs. There is a whole range of applications awaiting as researchers now have better toolkit at their disposal. Therefore this technique creates a platform in which different types of investigation related to genetic programs affecting the cell behaviour can be carried out. 

Journal Reference: Nature Methods

Grand prismatic spring

Origin of complex life could be revealed by mysterious life form grown in laboratory

Scientists ran a DNA analysis on a sediment core which was found on the floor of the Arctic Ocean in 2010. A previously unknown organism which belongs to the domain of microbes called Archaea appeared to have genomic characteristics of an entirely different domain known as Eukaryota. The discovery is named Lokiarchaeota, after the Loki’s Castle hydrothermal vent near Greenland where it was found. There were doubts about the contamination in the core but Japanese scientists have isolated Lokiarchaeota, and grown it in a lab. Researchers can now freely study and interact with Lokiarchaeota, which could help find our first ancestors on Earth. The work can be found here.

The tree of life has 3 major domains which start with bacteria – single-celled microbes without a nucleus and move around with flagella. Another domain is eukaryotes, which contain cells with a nucleus and a membrane which includes humans, plants, animals, etc. There is another domain Archaea which are like bacteria which lack nuclei and membrane-bound organs and move using flagella. The differences include their cells walls and RNA which are found to be different.

Later came the Lokiarchaeota followed by Thorarchaeota, Odinarchaeota and Heimdallarchaeota which show eukaryotic characteristics. They were collectively named Asgard archaea and is believed to be the origin of eukaryotic life. The sediment was retrieved from a seabed in Nankai Trough (2533 meters below sea level). On performing RNA analysis of their rich sample revealed the presence of a Lokiarchaeota-like organism. They cultivated their samples for 5 years in methane fed continuous flow bioreactor system which mimics deep-sea methane vents. Eventually, the microbes multiplied. The samples were placed in glass tubes in a bioreactor to keep it growing and finally, a very faint population of Lokiarchaeota grew after another year.

The team invested in isolation, cultivating and growing this slow dividing population. Lokiarchaeota took 20 days where a normal bacterium takes an hour and a half to double. The culture has 30-60 lag phase and 3 months to reach full-grown phase. Variation of growth parameters, combinations and concentrations did not significantly improve the lag phase and growth. The experiment took 12 years in total. The researchers named their cultivated microbe Prometheoarchaeum syntrophicum.

Various findings included Prometheoarchaeum which grows in the presence of one or two microbes (archaeon Methanogenium and bacterium Halodesulfovibrio). Prometheoarchaeum helps in breaking down amino acids into food, hydrogen is produced which is fed upon by other microbes. Prometheoarchaeum’s slow growth could be hampered by the presence of hydrogen. Examining the organisms in an electron microscope found the unusual shape for archaeon which has long tentacles sprouting from its body between which partner microbes are nested. With the increase of oxygen on Earth, it might have switched relationship to an oxygen-using bacteria, leading to eukaryotic life.

DNA sequencing revealed the eukaryotic characteristics that were observed in the rest of the Asgard archaea. More work has to be done as there is no definitive proof that eukaryotes evolved from archaea and Prometheoarchaeum might be quite different from the archaea of billions of years ago. The work is yet to be peer-reviewed but whatever be the results it is a monumental paper behind which a vast amount of perseverance.

Research Paper: Isolation of an archaeon at the prokaryote-eukaryote interface