Cloud Seeding |
Why in News: IIT Kanpur has suggested employing cloud seeding to induce “artificial rain” as a measure to mitigate air pollution in the national capital.
About Cloud Seeding
- Alternative Rainmaking:Cloud seeding, an artificial technique, encourages rainfall by introducing substances like silver iodide, potassium iodide, and dry ice into the atmosphere via aircraft.
- Condensation Catalysts:These particles act as nuclei for water droplets to gather around, facilitating raindrop formation. Typically, rain can occur within approximately thirty minutes of employing this method.
- Cloud Seeding Techniques:
- Hygroscopic Method: This approach aims to hasten droplet coalescence within clouds, fostering the creation of larger droplets that lead to rainfall. Salt particles are dispersed at the base of the cloud in this method.
- Glaciogenic Method: Here, the focus is on prompting ice formation in supercooled clouds, ultimately triggering precipitation. It entails dispersing potent ice nuclei, such as silver iodide particles or dry ice, into the cloud, initiating heterogeneous ice nucleation.
Green Crackers |
Why in News: The Supreme Court made it clear that its ruling prohibiting barium and other prohibited chemicals in fireworks is applicable nationwide, extending beyond just the National Capital Region.
About Green Crackers
Green crackers, as per CSIR-National Environmental Engineering Research Institute (CSIR NEERI), are fireworks designed with a smaller casing, devoid of ash, and may contain additives like dust suppressants to diminish emissions, particularly particulate matter.
- Chemical Composition: Unlike conventional fireworks, green crackers do not incorporate barium compounds. Instead, they utilize alternative substances such as potassium nitrate and aluminum, contributing to their characteristic green hue.
- Environmental Impact:The combustion of green crackers results in the production of water vapor, thereby reducing the release of dust particles into the atmosphere.
- Categories of Green Crackers:
- SWAS:Abbreviating “safe water releaser,” SWAS crackers feature a small water reservoir that vaporizes upon ignition.
- STAR: Referred to as a safe thermite cracker, STAR crackers exclude potassium nitrate and sulfur, emitting lower levels of particulate matter with reduced sound intensity.
- SAFAL: This category emphasizes safety with minimal aluminum content, opting for magnesium as a substitute while minimizing the usage of aluminum.
Color | Compound | Hazard |
BLAZING REDS | Lithium compounds | Toxic, irritating fumes when burnt |
GLITTERING GREENS | Barium nitrate | Respiratory tract irritation, potential radioactive fallout |
BRILLIANT WHITES | Aluminium | Contact dermatitis, bioaccumulation |
BLUES | Copper compounds | Cancer risk, bioaccumulation |
GLITTER EFFECTS | Antimony sulphide | Toxic smoke, potential carcinogens |
Human-Animal Conflict |
Why in News: The Elephant Lovers Forum in Palakkad has expressed apprehension regarding suspected incidents of poaching and hunting attempts by individuals residing on the outskirts of forests in Kerala.
About PT-7 or Palakkad Tusker-7:
- PT-7 serves as the code name for a renegade elephant known to roam the adjacent regions of Palakkad, Kerala.
- Definition of Kumki: Kumki, also referred to as Koomkie in Indian parlance, denotes captive Asian elephants specially trained to assist in operations aimed at trapping wild elephants.
CRISPR Technology |
CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats.
- CRISPR-Cas9 Technology:
- CRISPR-Cas9 enables editing of the genome by modifying DNA sequences.
- It allows for removal, addition, or alteration of specific sections of DNA.
- Components of CRISPR-Cas9 System:
- Cas9:Acts as molecular scissors, cutting DNA at precise locations.
- Guide RNA (gRNA):Designed to bind to specific DNA sequences and direct Cas9 to the target location.
- DNA Editing Process:
- Cas9, guided by gRNA, cuts both strands of DNA at the desired location.
- The cell detects the DNA damage and initiates repair mechanisms.
- Repair Mechanism:The cell’s repair machinery modifies the DNA, introducing changes to targeted genes.
- Natural Inspiration:CRISPR technology mimics a defense mechanism found in bacteria, which protects against viral attacks using a similar method.
Gene Therapy for Sickle Cell Anaemia |
Why in News: Victoria Gray from the United States has made history as the first person worldwide with sickle cell anemia (SCA) to achieve recovery through groundbreaking gene-editing treatment.
About Sickle Cell Anaemia (SCA)
- Genetic Basis:SCA is a genetic disorder resulting from mutations in genes responsible for carrying hemoglobin, causing red blood cells to take on a crescent shape.
- Health Implications: This abnormal shape can hinder blood flow, triggering intense pain, organ impairment, strokes, and various complications.
- Treatment Options:Presently, the primary solution for SCA worldwide involves bone marrow transplants, requiring a closely matched donor and carrying rejection risks.
How the Gene Therapy for SCA Works?
- CRISPR-Cas9 Technique:Involves modifying the patient’s DNA by targeting and replacing the faulty haemoglobin gene with a healthy one.
- Procedure:Stem cells are extracted from the bone marrow, edited in a laboratory, and reintroduced into the patient.
- Outcome:This restores normal haemoglobin function, offering a potential lifelong cure.
- Patient Trials:Approximately 29 patients, including Gray, received the treatment, with 28 experiencing pain relief and undergoing follow-up for sustained recovery.
- Broad Application:The therapy also benefits patients with transfusion-dependent ß-thalassemia.
- Regulatory Approval:The UK recently approved the therapy, named Casgevy, making it the first country to do so. It stands out as the sole permanent, innovative, and pioneering gene-editing treatment option available.
Whole Genome Sequencing |
Why in News: The Indian Institute of Science Education and Research (IISER) Bhopal has recently conducted Whole Genome Sequencing of banyan (Ficus benghalensis) and peepal (Ficus religiosa) using leaf tissue samples.
About Whole Genome Sequencing
Each living being, including bacteria, plants, and mammals, possesses a unique genetic blueprint known as the genome, composed of nucleotide bases. Whole genome sequencing is a technique employed in laboratories to swiftly determine the sequence of these bases within an organism’s genome.
Steps Involved in Whole Genome Sequencing
Process | Description |
DNA shearing | Scientists begin by using molecular scissors to fragment the DNA of any organism (e.g., bacteria) into smaller segments, making them readable by the sequencing machine. |
DNA barcoding | Tiny DNA tags, or barcodes, are attached by scientists to the fragmented DNA to distinguish which segment belongs to which organism. |
DNA sequencing | l Various bacteria’s barcoded DNA fragments are combined and inserted into a DNA sequencer. l The sequencer discerns the A, C, T, and G bases in each bacterial sequence. l Utilizing the barcode, the sequencer tracks which bases correspond to which bacterium. |
Data analysis | l Bioinformatic tools are employed by scientists to compare sequences from different bacteria, identifying discrepancies. l The extent of differences between bacteria can indicate their level of relatedness. |