Bio computers (GS Paper 3, Science and Tech)
Why in news?
- Scientists at Johns Hopkins University (JHU) recently outlined a plan for a potentially revolutionary new area of research called “organoid intelligence”.
- It aims to create “biocomputers”, where brain cultures grown in the lab are coupled to real-world sensors and input/output devices.
- The scientists expect the technology to harness the processing power of the brain and understand the biological basis of human cognition, learning, and various neurological disorders.
What is the premise of this technology?
- Understanding how the human brain works has been a difficult challenge. Traditionally, researchers have used rat brains to investigate various human neurological disorders.
- In a quest to develop systems that are more relevant to humans, scientists are building 3D cultures of brain tissue in the lab, also called brain organoids.
- These “mini-brains” (with a size of up to 4 mm) are built using human stem cells and capture many structural and functional features of a developing human brain. Researchers are now using them to study human brain development and test drugs to see how they respond.
- However, the human brain also requires various sensory inputs (touch, smell, vision, etc.) to develop into the complex organ it is, and brain organoids developed in the lab aren’t sophisticated enough. The organoids currently also don’t have blood circulation, which limits how they can grow.
Aren’t there other ways to study the human brain?
- Recently, scientists transplanted these human brain organoid cultures into rat brains, where they formed connections with the rat brain, which in turn provided circulating blood.
- Since the organoids had been transplanted to the visual system, when the scientists showed the experimental rats a light flash, the human neurons were activated, too, indicating that the human brain organoids were also functionally active.
- Scientists have touted such a system as a way to study brain diseases in a human context. However, human brain organoids are still nested in the rat-brain microenvironment, including the non-neuronal cells that play a critical role in some neurological diseases.
- The effects of drugs in this model will also have to be interpreted through various behavioural tests in rats, which could be insufficiently representative. So there is need to address the limitations of lab-grown organoids and develop a more human-relevant system.
What is the new ‘bio-computer’?
- The JHU researchers’ scheme will combine brain organoids with modern computing methods to create “bio-computers”. They have announced plans to couple the organoids with machine learning by growing the organoids inside flexible structures affixed with multiple electrodes (similar to the ones used to take EEG readings from the brain).
- These structures will be able to record the firing patterns of the neurons and also deliver electrical stimuli, to mimic sensory stimuli. The response pattern of the neurons and their effect on human behaviour or biology will then be analysed by machine-learning techniques.
- Recently, scientists were able to grow human neurons on top of a microelectrode array that could both record and stimulate these neurons.
- Using positive or negative electric feedback from the sensors, they were able to train the neurons to generate a pattern of electrical activity that would be generated if the neurons were playing table tennis.
What are the opportunities for ‘bio-computers’?
- While human brains are slower than computers at, say, simple arithmetic, they outshine machines at processing complex information.
- Brain organoids can also be developed using stem cells from individuals with neurodegenerative diseases or cognitive disorders. Comparing the data on brain structure, connections, and signalling between ‘healthy’ and ‘patient-derived’ organoids can reveal the biological basis of human cognition, learning, and memory.
- They could also help decode the pathology of and drug development for devastating neurodevelopmental and degenerative diseases such as Parkinson’s disease and microcephaly.
Are ‘bio-computers’ ready for commercial use?
- Currently, brain organoids have a diameter of less than 1 mm and have fewer than 100,000 cells (both on average), which make it roughly three-millionth the size of an actual human brain. So scaling up the brain organoid is key to improving its computing capacity – as will incorporating non-neuronal cells involved in biological learning.
- Second, researchers will also have to develop microfluidic systems to transport oxygen and nutrients, and remove waste products. These hybrid systems will generate very large amounts of data (i.e. of neural recordings from each neuron and connection), which researchers will need to store and analyse using ‘Big Data’ infrastructure.
- They will also need to develop and use advanced analytical techniques (with help from machines) to correlate the structural and functional changes in the brain organoids to the various output variables.
- There is also a proposal to have an ethics team to parallelly identify, discuss, and analyse ethical issues as they arise in the course of this work.
Low-cost paper microscope’s wider application in research
(GS Paper 3, Science and Tech)
Why in news?
- Researchers from the Indian Institute of Science (IISc) have reported that a cheap microscope connected to a smartphone camera could find wider application in many areas, and in some cases potentially replace more expensive equipment.
- The Foldscope is a handheld microscope made mostly of paper that can be connected to a smartphone camera.
- It has a magnification of around 140x and can identify objects just 2 micrometres wide. It was created by the Stanford University researchers in 2014 and costs around ₹400.
Applications of foldscope:
- The researchers found that foldscopes could capture the roundness and aspect ratio of an object to within 5% of those captured by state-of-the-art instruments called scanning electron microscopes (SEM), which cost more than ₹50 lakh each.
- The foldscopes can be used in pharmaceuticals (to inspect drug products), environmental science (pollutants), and cosmetics (powders and emulsions), among other areas.
Soil particles morphology:
- The foldscopes can be used to study “soil particles’ morphology”, which can “help understand soil structure, nutrient availability, and plant growth” in agriculture. Their focus was on the shape of soil grains.
- India’s soil classification scheme doesn’t include grain shape because measuring it accurately is “complex” and due to “the limited availability of affordable image capturing instruments”. The scheme classifies soil based on size, consistency, and susceptibility to deformation.
- Yet, shape matters because it influences how much water some soil can hold and how the soil responds to physical stresses.
How research was conducted?
- The classification schemes work around the difficulties of assessing shape by using other measures. They collected sand from four places in 2018: the beds of the Manu and the Brahmaputra rivers, sand unearthed by an earthquake in Tripura in 2017, and sand from a metre underground in Kalpakkam, Tamil Nadu. All four were coarse-grained soil with particles 0.32-0.47 mm wide.
- They used two instruments ; a foldscope attached to a 64MP smartphone camera and a SEM to measure three attributes: roundness (the extent to which a particle is spherical), aspect ratio (how wide it is compared to how tall it is), and circularity (the extent to which it is circular in two dimensions). In each case, they captured an image with an instrument and analysed it using a software called ImageJ.
Outcome:
- They found that the foldscope-based and the SEM-based readings differed by around 5% for roundness and aspect ratio for all sands, except the Tripura sand, whose measures differed by 9%. But the circularity readings differed by 50%.
- The researchers attribute this to the foldscope’s resolution and future studies could find a solution, including by enhancing the software.
- The researchers found that each foldscope couldn’t be used to image more than “150-200 particles” at a time because its focusing mechanism wears out. But this was balanced by the instrument’s portability and affordability.
With overfishing, great seahorses bolt from Coromandel
(GS Paper 3, Environment)
Why in news?
- Extensive fishing off the Coromandel Coast could be forcing the great seahorse to migrate laboriously toward Odisha.
Details:
- Fishing is less intense in the Bay of Bengal off the Odisha coastline. However, the shallow coastal ecosystem of the eastern Indian State may not be the new comfort zone for the fish with a horse-like head, according to a recent study.
- The study was based on a specimen of a juvenile great seahorse, or Hippocampus kelloggi, caught in a ring net and collected from the Ariyapalli fish landing centre in Odisha’s Ganjam district.
Vulnerable species:
- There are 46 species of seahorses reported worldwide. The coastal ecosystems of India house nine out of 12 species found in the Indo-Pacific, one of the hotspots of seahorse populations that are distributed across diverse ecosystems such as seagrass, mangroves, macroalgal beds, and coral reefs.
- These nine species are distributed along the coasts of eight States and five Union Territories from Gujarat to Odisha, apart from Lakshadweep and the Andaman and Nicobar Islands.
- The population of the great seahorse, which is among the eight species tagged ‘vulnerable’, is declining due to its overexploitation for traditional Chinese medicines and as an ornamental fish, combined with general destructive fishing and fisheries bycatch.
Threat:
- Despite the ban on fishing and trading activities on seahorses from 2001, clandestine fishing and trading still take place in India.
- This creates immense pressure on the seahorse populations that have a high dependence on local habitats to maintain their extensive and long-life history traits.
Long migration:
- Seahorses are poor swimmers but migrate by rafting, clinging to floating substrata such as macroalgae or plastic debris for dispersal by ocean currents to new habitats for successful maintenance of their population.
- However, the 1,300-km northward migration of the great seahorse from the Palk Bay and the Gulf of Mannar to Odisha is likely a response to extensive fishing activities around the southern coast of India.
- The species is abundant off the Coromandel Coast (Andhra Pradesh and Tamil Nadu), but is under extensive fishing pressure, with 13 million individuals caught a year.
Way Forward:
- This calls for increased monitoring of the coastal ecosystems of India on the east coast for better conservation and management of the remaining seahorse populations.
