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Hamas’ surprise attack on Israel

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Hamas’ surprise attack on Israel

 

Why in the News?

Israel witnessed the largest attack from Gaza, the tiny Palestinian enclave, resulting in one of the worst security crises in 50 years.

News in Detail:

  1. A highly coordinated attack on Israel that involved Hamas militants infiltrating Israeli cities, hitting military bases and killing and taking hostage soldiers and civilians.
  2. The attacks were a reminiscent of the 1973 Yom Kippur holiday attack by Egyptian and Syrian troops.
  3. The attack has resulted in at killing of 200 people and hundreds injured.
  4. Israel’s right-religious government led by Prime Minister Benjamin Netanyahu which holds a key promise of Israel’s security, has declared war on Hamas.

Why did Hamas launch the massive incursion into Israel?

  1. Deterioration of Palestine-Israel relations in the recent years.
    1. Military raids almost on a daily basis, has been carried out by Israel in the occupied West Bank, which has so far resulted in death of ~ 200 Palestinians and 30 Israelis in this year.
    2. Jerusalem’s Al Aqsa Mosque compound, Islam’s third holiest place of worship was raided by Israeli police, which led to rocket attacks from Gaza.
    3. Israel carried out a major raid in the West Bank town of Jenin, which has emerged as a hotbed of militancy in the West Bank.
  2. Accumulation of anger and violence among Palestinians against both the Israeli occupiers as well as the Palestinian Authority.
    1. Thus, a massive attack from Gaza controlled by Hamas is a call for “all Arabs of Palestine”, including the Israeli Arab citizens (20% of the Israel’s population), to take up arms against the state of Israel.
    2. Hamas is trying to emerge as the sole pole of the Palestinian cause by trying to cash in on the public anger against occupation.
  3. Divisions in Israeli society
    1. The most right-wing government of Israel is pushing for reforms to overhaul the structures of power so as to gain supremacy over other institutions. 
    2. For instance, the ambitious legislative agenda seeking to curtail the powers of the judiciary through Parliament witnessed massive protests.
    3. There are resenting voices even within the military and rights groups are up in arms showing deep divisions in society.
    4. Hamas could have perceived that Israel was at a weak moment internally and launched an unprecedented attack.
  4. Geopolitical angle
    1. Israel and Saudi Arabia are in an advanced stage of normalisation talks which might have led to the Hamas attack.
    2. If Saudi Arabia, the custodian of the two holiest mosques of Islam & the most influential Arab country normalises ties with Israel, it can lead to reset of West Asian geopolitical dynamics and also put Hamas at a further disadvantageous position.
    3. Such a realignment is against the interests of Iran (which backs the Islamic Jihad and Hamas) and Lebanon’s Hezbollah.

Significance of quantum dots in nanotechnology

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Significance of quantum dots in nanotechnology

 

 

Why in the News?

The Nobel Prize for chemistry 2023 was awarded to Alexei I. Ekimov, Louis E. Brus, and Moungi G. Bawendi “for the discovery and synthesis of quantum dots”.

What is a quantum dot?

  1. It is a small assembly of atoms around a few nanometres wide.
  2. The small assembly of atoms gives very little space to the electrons in these atoms to move around, which leads it to displays the effects of quantum mechanics.
  3. Quantum dots are also called ‘artificial atoms’ as the dot as a whole behaves like an atom in some circumstances.

Why are they of interest?

  1. There are two broad types of materials:
    1. Atomic- it refers to individual atoms and their specific properties.
    2. Bulk- it refers to large assemblies of atoms and molecules.
  2. Quantum dots behave in ways that neither atoms nor bulk materials do.
  3. A distinguishable behaviour of quantum dots is that the properties of a quantum dot change based on its size.
  4. Also, when light is shined on a quantum dot, it absorbs and then re-emits it at a different frequency.
    1. Smaller dots emit bluer light
    2. Larger dots, redder light.

Work of the Awardees:

  1. In 1980s, Louis Brus and Alexei Ekimov succeeded independently creating quantum dots, which are nanoparticles so tiny that quantum effects determine their characteristics.
  2. In 1993, laureate Moungi Bawendi revolutionised the methods for manufacturing quantum dots, making their quality extremely high – a vital prerequisite for their use in today’s nanotechnology.
  3. Usually, every element exhibits specific properties which will be same regardless of its size. This form one of the fundamental facts of chemistry.
  • For instance, a piece of pure gold, whether it is a large 100-gram piece or a small 10 milligram one, has exactly the same properties.
  1. However, very small particles, in the nanoscale range (1 to 100 billionth of a metre) behave slightly differently from larger particles of the same element. 
  2. Alexei Ekimov was the first to notice this deviant behaviour in Copper Chloride nanoparticles around 1980, and manufacture these nanoparticles to show this change in behaviour.
  3. Louis Brus, an American scientist working independently, discovered similar behaviour in Cadmium Sulphide nanoparticles.
  4. The deviant behaviour of small nanoparticles arises because of the emergence of quantum effects.
  5. The quantum theory explains that, usually, electrons move around in a large empty space, relatively, outside the nucleus of the atom but when the size of the particles is reduced drastically, electrons in the atoms find themselves increasingly squeezed giving rise to the strange quantum effects.
  6. Such strange effects and special properties were found in nanoparticles and hence were called quantum dots.

What are quantum dots’ applications?

  1. Surgical oncology
  2. Advanced electronics including semiconductors.
  3. Quantum computing.
  4. Solar cells can be made as quantum dots as they have a thermodynamic efficiency as high as 66%.
  5. Multiplexer in telecommunications.
  6. Hasten chemical reactions that extract hydrogen from water

mRNA research that was used to fight COVID

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mRNA research that was used to fight COVID

Why in the News?

The Nobel Prize for Physiology or Medicine, 2023 was awarded to Katalin Karikó and Drew Weissman for their “discoveries concerning nucleoside base modifications that enabled the development of mRNA vaccine technology.

What are mRNA vaccines?

  1. mRNA (messenger RNA) is a form of nucleic acid which carries genetic information to code for proteins.
  2. mRNA vaccine attempts to activate the immune system to produce antibodies that can help counter an infection from a live virus.
  3. But unlike other vaccines that use weakened or dead bacteria or viruses to evoke a response from the immune system, mRNA vaccines only introduce a piece of the genetic material that corresponds to a viral protein such as spike protein (protein found on the membrane of the virus).
  4. mRNA was advocated as a vaccine platform since its development and offers strong safety advantages such as,
    1. It requires a minimal genetic construct, and so harbours only the elements directly required for expression of the encoded protein.
  5. Though mRNA can be used to get the cell to produce the necessary proteins, mRNA is very fragile and can be shred apart at room temperature or by the body’s enzymes when injected. Therefore, mRNA needs to be wrapped in a layer of oily lipids as a mRNA-lipid unit to most closely mimics how a virus presents itself to the body.
  6. mRNA vaccine for COVID-19:

 

 

The mRNA technology developed by the awardees:

  1. Messenger RNA (mRNA) is a template used for protein production when genetic information encoded in DNA is transferred to it.
  2. Proteins are the main structural component of cells which plays a key role in growth and repair.
  3. During the 1980s, in-vitro transcription method was developed which permitted the idea of using mRNA for vaccine and therapy.
  4. Karikó worked on developing mRNA for therapy despite challenges in delivery and inflammatory reactions and immunologist Weissman joined the work later.
  5.  In 2005, by making base modifications to the mRNA they managed to ease delivery paths and get rid of the inflammatory reactions. 
  6. In 2019, the scientists taught the mRNA vaccine to instruct human cells to make the S protein found on the surface of the COVID-19 virus.
  7. This caused the body to create antibodies which will fight the virus if the individual were to contract the infection. 

Significance of the Work:

  1. The technology became the foundation for history’s fastest vaccine development programme during the COVID-19 pandemic.
  2. The Nobel prize for Medicine has been awarded for a discovery that renders ‘greatest benefit on mankind’, which was done by the mRNA.
  3. Recognition of contribution of a woman of science:
  • 13 women have now won the Nobel Prize for Medicine (out of 225 awarded); and only 62 women have won any Nobel Prize (against 894 men) so far.

What were the down side of mRNA COVID vaccines:

  1. ‘Double spend’ imposed on the Consumers:
    1. most new drugs and vaccines development happens at the expense of governments and public funds, which are taxes paid by the public.
    2. Post patent/license acquisition, companies commoditise and commercialise these entities registering huge profits at the expense of the same people whose taxes funded the fundamental research.
  2. It fell short of targets such as
    1. Poorer countries became the victims of their subpar purchasing power.
    2. Did not have sufficient stocks of mRNA vaccines.

New tools to fathom the world of electrons

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New tools to fathom the world of electrons

Why in the News?

Recently Pierre Agostini, Ferenc Krausz and Anne L’Huillier have been awarded Nobel Prize in physics, 2023 for their contribution to making it possible to watch electrons move using experimental methods that generate attosecond pulses of light.

What is an attosecond?

  1. An attosecond is one quintillionth of a second, or 10^-18 seconds.
  2. An attosecond is the timescale at which the properties of an electron change, which makes it possible to study and truly understand electrons.

 

 

 

What is attosecond science?

  1. Attosecond science deals with the production of extremely short light pulses to study superfast processes.
  2. For instance, a hummingbird’s wings beat 80 times a second with each beat lasting 1/80th of a second, which is difficult for human eyes to capture (human eye can see up to 60 frames per second at its best).
  3. The solution can involve the use of digital camera that creates photographs by capturing light coming from a source using a sensor. It can be done on 2 ways:
    1. The aperture can be opened for exactly 1/80th of a second to capture the reflection.
    2. Alternatively, aperture can be kept open at all times and release a light pulse whose duration is 1/80th of a second towards the wing and capture the reflection. This is a better option to study electrons.

Significance of their work:

  1. Atoms or molecules make movements, or changes took place generally in picoseconds (10^-12) or femtoseconds (10^-15), which required unimaginably short pulses of light to capture their movement. For that femtosecond ‘photography’ was developed and was considered the limit.
  2. However, there were processes that were even faster in atoms happening within a few attoseconds (10^-18).
  3. Pierre Agostini, Ferenc Krausz and Anne L’Huillier worked
    1. Anne L’Huillier, 1988 witnessed the phenomenon of high-harmonic generation i.e., when a beam of infrared light is passed through a noble gas, the gas emitted light whose frequency was a high multiple of the beam’s frequency with a sharply declining light intensity and then plateaued and again declined.
    2. Later in 1994, A beam of light consists of oscillating electric and magnetic fields was imparted to electrons:
      1. The oscillating field would impart some energy to the electron and then take away from it.
      2. when energy is imparted, the electron would come loose from an atom, and when it is taken away, the electron and the atom would recombine, releasing some excess energy. This energy is the light re-emitted by the gas.
    3. They developed experimental methods that generate attosecond pulses of light for the study of electron dynamics in matter.
    4. They have demonstrated a way to create extremely short pulses of light that can be used to measure the rapid processes in which electrons move or change energy.
    5. RABBIT technique:
      1. A major technique to measure the duration of a short light pulse was developed by Pierre Agostini and his colleagues in 1994.
  4. The sub-atomic motion happens in a matter of attoseconds.
  • For instance, the dynamics of the electron are 100 to 1,000 times faster than that of the atom. This is because atom is heavier, because of the nucleus, and has greater inertia (Lower the inertia, faster the dynamics).
  1. They mixed the lights of different wavelengths, to produce attosecond pulses.
  2. Challenges in developing attosecond light pulses:
    1. To capture a process, the measurement must be made at a pace quicker than the rate of change.
    2. But, for all sorts of light produced by laser systems, this cycle used to take at least a few femtoseconds to complete.
  3. Possible applications:
    1. It has potential applications in a variety of areas, from electronics to medicine, across disciplines in physics, chemistry and biology.
    2. In medical science, particularly in finding therapies for cancer care.
    3. Study molecular-level changes in blood, to identify diseases.
    4. Create more efficient electronic gadgets by better understanding of how electrons move and transmit energy.