Angira Rastogi, winner of TYT 2020, delivers her talk at India Science Festival 2020.
Winners of Talk your Thesis - ISMO 2021
Arjun Kamdar
Jayashree Mazumder
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Bring attention to your work, bring your science to the world. Explain your thesis to a non-specialist audience, with a simple, crisp and insightful 10 min talk. 5 finalists will be selected through a competitive process judged by a jury.
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Eligibility: Anyone who is pursuing a MS/PhD/Postdoc or has recently completed one.
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Prizes: Cash prize along with the coveted title of becoming an ISF Fellow! 1st position: $400 2nd position: $250 3rd position: $150
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Need some inspiration? Here are our Finalists from 2020.
Search for physics beyond the Standard Model
Science is driven by curiosity and scientific curiosity comes from the desire to learn the facts of nature. We can understand natural phenomena by building a model based on certain assumptions.
Abstract
Science is driven by curiosity and scientific curiosity comes from the desire to learn the facts of nature. We can understand natural phenomena by building a model based on certain assumptions. These models can describe the phenomena as well as predict what lies ahead. A good discovery relies on the impeccable reproducibility of the detection and a good detection method is often associated with an elegant yet simple technique.
The standard model (SM) of elementary particles [1] is a successful milestone in our current understanding of fundamental phenomena happening in our universe. As a particle physicist and a member of the CMS collaboration, I am looking for evidence of new physics that lies beyond the SM. I'm trying to discover answers to some big mysteries of the universe like dark matter, hierarchy of the fundamental particle masses, or something even deeper... why we exist at all?
Like cells are the smallest unit of life, atoms are the basic building blocks of matter. An atom is a million times smaller than the thickness of a human hair and for many years was thought to be fundamental. But experiments in the late 19th and early 20th century unveiled atomic substructure and established the existence of even smaller constituents - electrons, protons and neutrons. These fundamental particles bind together using the electromagnetic force to form matter. Further, protons and neutrons are composed of quarks which bind together using the strong force, which is in fact the strongest interaction in nature at subatomic length scales. The final force in the SM is the weak force which is crucial for sustaining life on Earth. It powers our Sun through the thermonuclear process taking place at its core. Interestingly, the SM doesn't describe the fourth fundamental interaction, the gravitational force.
In the SM, there are three generations of matter, each composed of a charged lepton, a lepton neutrino and a pair of quarks. Thus, there are six leptons and six quarks; each of these twelve particles has its own antiparticle. In addition, there are four force carriers for the three forces of nature (the strong, weak and electromagnetic forces). Lastly, the higgs boson interacts through its field with all the particles and assigns them the masses that they have. However, the higgs boson does not interact with neutrinos and neutrinos are massless in the SM. Recently the neutrino oscillation experiments [2] established that at least two out of the three neutrinos have a very tiny non-zero mass. The mass mechanism as well as the smallness of neutrino masses is still an unsolved mystery. In my research, I am trying to solve this mystery.
In my group, we use leptons as a basic tool and construct a multilepton search strategy which has the advantage of having a high signal to noise ratio. The multilepton final state is a good probe because of the clean signature in the detector and less contamination from the known SM processes. In our analyses, we have looked for evidence of the type-III seesaw mechanism which explains the smallness of neutrino masses. We searched for three new heavy particles (two charged and one neutral sigma fermions) that couple to leptons and to a Higgs boson doublet [3]. We also searched for vector-like leptons using the same search strategy [4]. The vector-like leptons arise in a wide variety of models ranging from supersymmetry to extra dimensions. Currently, we are studying the neutrino minimal SM [5] which incorporates the seesaw mechanism, provides a suitable dark matter candidate, and gives a possible explanation of the matter-antimatter asymmetry that we observe in the universe. This model can also be probed with the help of leptons, especially those of the third generation.
To understand observations and find signs of new physics, it is very important to have a good handle on known SM processes. A powerful way to do this is through simulation. Detailed simulation of the detector uses substantial resources in terms of computing units and memory consumption. In CMS, we have developed an alternate fast simulation [6] which uses less resources but can be equally potent in describing certain physical phenomena. The CMS charged particle subdetector was upgraded in 2017 for longevity and an improved detection technique. I wrote the simulation software, to implement the new geometry of the upgraded detector, and the consequent modifications in the subdetector algorithms.
In my presentation, I will describe the multilepton search tool, the role of the upgraded simulation and some of the results of our search for physics beyond the SM.
[1] - Review of Particle Physics, M. Tanabashi et al. (Particle Data Group), Phys. Rev. D 98, 030001 (2018)
[2] - Evidence for oscillation of atmospheric neutrinos, Y. Fukuda et al. (Super-Kamiokande Collaboration), Phys. Rev. Lett. 81 1562-1567 (1998)
[3] - Search for Evidence of the Type-III Seesaw Mechanism in Multilepton Final States in Proton-Proton Collisions at √s=13 TeV, The CMS collaboration, Phys. Rev. Lett. 119, 221802 (2017)
[4] - Search for vector-like leptons in multilepton final states in proton-proton collisions at √s = 13 TeV, The CMS collaboration, Phys. Rev. D 100, 052003 (2019)
[5] - The ν MSM, Dark Matter and Neutrino Masses, Takehiko Asaka, Steve Blanchet, Mikhail Shaposhnikov, Phys. Lett. B. 631, 151-156 (2005)
[6] - Recent Developments in CMS Fast Simulation, The CMS collaboration, PoS ICHEP2016 181 (2016)
Full list of publications can be found here - http://inspirehep.net/search?ln=en&p=author%3AA.Rastogi.2+AND+collection%3Apublished
Angira Rastogi
IISER, Pune
Factors affecting lift generation in insects & birds
Flapping flight, typical in insects and birds, is known to generate large aerodynamic forces as compared to fixed-wing flight, as in airplanes. In a typical flapping cycle, the airfoil translates from one end of the stroke to another.
Abstract
Flapping flight, typical in insects and birds, is known to generate large aerodynamic forces as compared to fixed-wing flight, as in airplanes. In a typical flapping cycle, the airfoil translates from one end of the stroke to another. Near the ends of stroke, the airfoil goes through rotations, that are termed as pronation and supination. The underlying fluid phenomena are highly unsteady, and the production of high lift is attributed to primarily three factors --- delayed stall due to leading-edge vortex (LEV), rotational forces and wing-wake interactions.
Although these factors have been studied quite extensively, there is less clarity on the physics that underly these phenomena. This work attempts to understand how each of these factors affect lift generation and to what extent they contribute to the overall lift. For this purpose, we adopt an idealized set of kinematics. The airfoil translates from one end of stroke (A) to the other (B) at a constant pitch angle, $alpha$ (angle between the chord and the horizontal). After reaching the extreme position (B), it stops to translate and rotates to the new pitch angle, $(pi-alpha)$, about its quarter chord. After attaining the new orientation, it starts to translate back to point A at a constant pitch angle. It is noted that the airfoil never rotates and translates simultaneously at any point in the flapping cycle.
In reality, the translation and rotation overlap near the end of stroke. However, the reason for adopting this kinematics is that the lift response can now be demarcated into a translational part and a rotational part, and the lift peaks can be compared. In addition, the effect of wing-wake interactions can be measured by comparing the translational and rotational parts of the flapping response with that of the corresponding pure motions (pure translation being the airfoil translating from A to B in a quiescent medium and pure rotation being the airfoil rotating from $alpha$ to $(pi-alpha)$ while at point B, in a quiescent medium). All the cases are analyzed using CFD; immersed-boundary method.
Three cases of flapping are considered, with each case having exactly the same kinematics for translation, with the duration of translation being $t_t$ = 0.00892 s. They differ in the duration of rotation, with Case 1 having a rotation duration of $t_r$ = 0.01432 s and Cases 2 and 3 having half the duration of the previous case. These choices are such that for Case 3, flapping frequency is 40 Hz, a typical range for many insects like dragonflies. In addition, the cases of pure translation and pure rotations are considered for isolating the effects of wing-wake interactions.
In the case of pure translation, it is seen that the airfoil experiences an initial surge in lift associated with the rapid acceleration near the beginning of the stroke. The lift force drops a bit and then stabilizes at a constant value for the remaining stroke due to the sustenance of the LEV. The drop in lift is attributed to the fact that the LEV is still forming. At the end of the translation, lift drops owing to the rapid deceleration of the airfoil. In the cases of pure rotation, it is observed that the airfoil experiences higher forces for lower durations of rotation. It generates positive and negative peaks of nearly the same magnitude. Also, it is seen that the vortices generated are much stronger with increasing pitch rates.
In the cases of flapping, it is seen that in all three cases, the translational part generates higher lift as compared to the rotation part. The comparison of the flapping lift history with that of the pure cases reveals that the wing-wake interactions affect the translational part more significantly than the rotational part. The effect of wing-wake interaction in translation is more prominent in Case 3 as compared to Case 2 and even lesser in Case 1. The duration of rotation, therefore, decides the strength of the vortices shed into the wake and, thereby, the magnitude of the wing-wake interaction. Another interesting observation made is that the periodicity of the lift history changes in Case 3 with half the flapping frequency (20 Hz) showing up in the history. Further investigations are required to ascertain the reason for this behaviour.
In conclusion, it is inferred that translation happens to be a better contributor to lift generation compared to rotation. Also, wing-wake interactions affect the translational part of the flapping response more than the rotational part. Higher pitch rates generate stronger vortices, which result in stronger wing-wake interactions on the translational phase.
Link to journal and conference publications: https://drive.google.com/drive/folders/1tQruf2tBdYc2qVvGNAl1chIlNSp4hnXi?usp=sharing
Video link: https://drive.google.com/file/d/1gLyZQikYqNINuDo3U67Fr7JNHKRP5v-7/view?usp=sharing
Anand Bharadwaj S
IIT Madras
Control of unstart phenomena in scramjet engines
Scramjets or supersonic combustion air-breathing engines are for long being considered a revolutionary engine technology aiming to fly craft at high Mach number range of 5 to 15 and seamlessly integrating air-to-space operations
Abstract
Scramjets or supersonic combustion air-breathing engines are for long being considered a revolutionary engine technology aiming to fly craft at high Mach number range of 5 to 15 and seamlessly integrating air-to-space operations [1] primarily to synthesize a launch vehicle for achieving single-stage to orbit or SSTO and air to surface hypersonic cruise missiles. In late 1950’s U.S.A.F., U.S. Navy and NASA began developing scramjet engines and performed several tests at Langley Research Centre [1]. There have been numerous test runs throughout the world like Hypersonic Research Engine/HRE (NASA), Boeing X-51, X-41 (U.S.A.F), HyShot(Australia, US & UK), ATV (India) which has involved billions of dollars spent in R&D. Despite huge investment, this great future technology is still under wraps because of a common problem of inlet unstart i.e. choking of the inlet of the scramjet engine by high pressure fluid.
Physical experimental setup incurs huge cost and the numerical method involving Computational Fluid Dynamics for hypersonic flows always pose challenges due to complexities and scarce experimental data. Present study initially focuses on numerical methodology development for modelling supersonic combustion using 8 species, 13-reaction chemical model validated against benchmark supersonic combustion experiment at DLR test facility. Similar methodology has been further used to model the unstart phenomenon in a modified scramjet geometry of Wagner et al.[4], where sudden heat release caused by combustion was also used to generate unstart along with lifting of flap[3]. Control System mitigating unstart by leaking high-pressure fluid from the slots (bleeding) designed on lower wall or cowl (2D) and sidewall (3D) is suggested. Slot’s size and position effect on mechanism’s efficacy is studied and an automatic slot control mechanism to control unstart is proposed. Bleeding effect on engine performance parameters is also explored.
Further, the work focuses on discovering the underlying phenomenon behind the control method’s efficacy. Scramjet inlet’s compression system involves complex phenomenon featuring shock-shock interaction, shock-boundary layer interaction, flow separation, separation bubble-boundary layer interaction etc. Pressure losses and deteriorated engine performance parameters is preceded by flow separation bubble consequently resulting in unstart. Therefore, measures must be taken to reduce the interaction between shock-boundary layer and separation bubble. Boundary Layer manipulations have extensively been studied to reduce the pressure loss associated with shock/turbulent-boundary-layer interactions. Passive control methods such as suction[5], blowing [6] affect the boundary layer by generating turbulence which in turn enhances the momentum transfer in the boundary layer while delaying boundary-layer separation [7]. Various device shapes, such as grooves, slots and slits combined with passive cavities[8,9] have been used to modify shock boundary-layer interaction through streamwise vortex generation. Bleeding controls boundary-layer growth and shock induced boundary-layer separation [10]. Bleeding away the near-wall boundary layer at certain locations improves pressure recovery and reduces shock instabilities and extends the manoeuvring range. Kouchi et al [10] experimentally showed that bleeding of 0.65% captured airflow effectively suppressed boundary layer separation, improved unstart characteristics and doubled engine’s operating range. Bleeding implementation leads to a reduction of the separation bubble thickness (~50%) and vortex-induced localized thermal loads.
Bibliography
* This work is selected to be presented at AIAA Scitech Forum and Exposition 2020 (between NASA & Lockheed Martin) at USA
[1] James Ramsay Drummond, Marc Bouchez, and Charles R. Mcclinton, editors. CHAPTER 1: OVERVIEW OF NATO BACKGROUND ON SCRAMJET TECHNOLOGY. NASA Technical Reports Server, 2005
[2] Wikstrom N. Berglund, M. and C. Fureby. Numerical simulation of scramjet combustion. Swedish Defence Research Agency, 2005.
[3] R. Pecnik I. Jang and P. Moin. A numerical study of the unstart event in an inlet/isolator model. Stanford Center for Turbulence Research Annual Research Beliefs, 2010.
[4] Justin Wagner, Kemal Yuceil, and Noel Clemens. Piv measurements of unstart of an inlet-isolator model in a mach 5 flow. In 39th AIAA Fluid Dynamics Conference, 2012
[5] M. J. MORRIS, M. SAJBEN, and J. C. KROUTIL. Experimental investigation of normal-shock/turbulent-boundary-layer interactions with and without mass removal. AIAA Journal, 30(2):359–366, 1992.
[6] Jean M. Delery. Shock wave/turbulent boundary layer interaction and its control. Progress in Aerospace Sciences, 22(4):209 – 280, 1985
[7] D. C. MCCORMICK. Shock/boundary-layer interaction control with vortex generators and passive cavity. AIAA Journal, 31(1):91–96, 1993
[8] Everett S. Hafenrichter, Yeol Lee, J. Craig Dutton, and Eric Loth. Normal shock/boundary-layer interaction control using aeroelastic mesoflaps. Journal of Propulsion and Power, 19(3):464–472, 2003
[9] T. I.-P. SHIH, M. J. RIMLINGER, and W. J. CHYU. Three-dimensional shockwave/boundary-layer interactions with bleed. AIAA Journal, 31(10):1819–1826, 1993
[10] Toshinori Kouchi, Tohru Mitani, and Goro Masuya. Numerical simulations in scramjet combustion with boundary-layer bleeding. Journal of Propulsion and Power, 21(4):642–649, 2005
Anchal Varshney
Aligarh Muslim University
Potential role for the onset of recombination events
Viral characteristics associated with maintenance of elite neutralizing activity in chronically HIV-1 clade C infected monozygotic pediatric twins: Implications for vaccine design
Abstract
Viral characteristics associated with maintenance of elite neutralizing activity in chronically HIV-1 clade C infected monozygotic pediatric twins: Implications for vaccine design
Nitesh Mishra1, Muzamil Ashraf Makhdoomi1,2, Shaifali Sharma1, Sanjeev Kumar1, Deepshika Kumar1, Himanshi Chawla1, Ravinder Singh3, Uma Kanga4, Bimal Kumar Das3, Rakesh Lodha5, Sushil K Kabra5, Kalpana Luthra1.
1Department of Biochemistry, 3Department of Microbiology, 4Department of Transplant Immunology and Immunogenetics, 5Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India. 2Department of Biochemistry, Government College for Women, Cluster University Srinagar, Srinagar, India.
Abstract
HIV, or human immunodeficiency virus is a retrovirus that primarily infects CD4 T cells, one of the key players of our immune system. HIV-1 envelope glycoprotein (env), a trimer of heterodimer containing gp120 and gp41 subunits, mediates viral entry, and is the sole target of broadly neutralizing antibodies (bnAbs), though bnAbs only develop in <10-15% of infected individuals. A protective HIV-1 vaccine capable of inducing such bnAbs is needed, but few candidates, with BG505.SOSIP.664 being the prominent one, capable of doing so are known (1). Extensive genetic diversity due to an error prone reverse transcriptase further impedes the search for capable HIV-1 vaccine candidates. In infected children, bnAbs with multiple epitope specificities, a feature seen only in children, evolve over several years of infection (2-4). Elite neutralizers are top 1% of HIV-1 infected individuals with highly potent plasma antibodies capable of neutralizing diverse strains of HIV-1 (5). Chronically HIV-1 infected children with elite plasma neutralizing activity are suitable candidates to understand the mechanisms leading to the co-evolution of virus and antibody response targeting multiple epitopes, and to identify viral strains capable of serving as vaccine candidates.
Herein, we report longitudinal diverse co-evolution of bnAbs and circulating viral variants in a pair of genetically identical twins over a period of 60 months, even though they were infected at the same time point, had the same source of infection, and similar CD4+ T cell counts, with an added advantage of assessments at matched time points between two infected individuals belonging to one transmission pair. To study the evolutionary course of HIV env in the context of an elite neutralizing serological response, circulating viral variants from twins were generated, and assessed for their vulnerability to autologous plasma antibodies, known bnAbs and non-nAbs. Plasma neutralization activity was assessed by standardized TZM-bl based neutralization assay (6). Utilizing standard HIV virus panel reflective of the global env diversity, and single base mutants, we assessed the plasma antibody neutralizing activity, characterized the epitopes against which the antibody response was directed. In addition, chimeric viruses were generated by domain swapping to assess escape pathways utilized by HIV-1 to gain resistance to contemporaneous autologous plasma bnAbs as well as assessed the features associated with maintenance of elite plasma neutralizing activity.
The plasma from both donors, sharing a similar genetic makeup and infecting virus, showed the evolvement of bnAbs targeting common epitopes in the V2 and V3 regions of the envelope, suggesting bnAb development in these twins may perhaps be determined by specific sequences in the shared virus that can eventually guide the development of immunogens aimed at eliciting V2 and V3 bNAbs. Elite plasma neutralizing activity was observed since the initial sampling at 78 months of age in AIIMS_330 and persisted throughout, while in AIIMS_329 it was seen at 90 months of age, after which the potency decreased over time. Viral diversity characterization showed higher diversity in AIIMS_330 with majority of the viral variants sensitive to autologous plasma antibodies compared to AIIMS_329 in whom the circulating viral variants were resistant to autologous plasma antibodies. Evolution of env was studied in both twins to identify the influence of discrete env evolutionary pathway on distinct plasma nAb neutralization potential. No distinguishing features were observed between twins in terms of evolutionary rates, overall viral diversity, bnAb epitope diversification or evolutionary resistance pathways for known bnAbs. However, in AIIMS_330 only, prominent recombination events were observed. The evolving recombinants in AIIMS_330 showed positively selected residues within bnAb epitopes compared to non-recombinants viruses in AIIMS_329. The viral env diversification pathway observed in AIIMS_330 provides key clues for the development of sequential and cocktail immunization strategies. In addition, we describe two HIV-1 envelope glycoproteins, 329.14.B1 and 330.16.E6, isolated from AIIMS_329 and AIIMS_330. 329.14.B1 and 330.16.E6 were susceptible to all major known bnAbs targeting the key sites of vulnerability and were capable of binding bnAbs in their native forms. Heterologous plasmas from HIV-1 infected infants potently neutralized the pseudoviruses with 329.14.B1 and 330.16.E6 envelope glycoprotein, suggesting antibodies capable of recognizing these envelopes exist in HIV-1 infected infants of Indian origin. Envelopes were resistant to soluble CD4 and non-neutralizing antibodies. Glycan shield mapping showed both envelope glycoprotein with intact glycan shield, offering another advantage as completely glycan shielded viruses are associated with accelerated neutralization breadth development (7-8).
Our data, acquired in HIV-1 infected monozygotic pediatric transmission pair, suggests a potential role for the onset of recombination events and positive selection within bnAb epitope in development of elite plasma neutralizing activity.
Abstract Body Count – 742 words
This work was published in two papers in Journal of Virology
https://drive.google.com/open?id=1zbZvJpAuPGcwhhJwi6kzZoMW-DQ-Cdsh
https://drive.google.com/open?id=1mFdlU4mCAmxiIBMs3kll_6p_mCSjGpup
Video
https://drive.google.com/open?id=194dyyZZb26X_xgpNX9L0LLt0feZvxrXM
Previously Published Papers
https://drive.google.com/open?id=1Si5i4U6VYqpLd0ebHnlbx6hJ000JLyTc
https://drive.google.com/open?id=17Oz1iT8Ipv3NW0IOQfGSpUR-W4GVbJM9
https://drive.google.com/open?id=1ninqp9t4EPFazBmCNUiXn223CHtjHydf
Bibliography
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3.Ditse Z, Muenchhoff M, Adland E, Jooste P, Goulder P, Moore PL, Morris L. 2018. HIV-1 subtype C-infected children with exceptional neutralization breadth exhibit polyclonal responses targeting known epitopes. J Virol 92:e00878-18. https://doi.org/10.1128/JVI.00878-18.
4.Goo L, Chohan V, Nduati R, Overbaugh J. 2014. Early development of broadly neutralizing antibodies in HIV-1-infected infants. Nat Med 20:655–658. https://doi.org/10.1038/nm.3565.
5.Simek MD1, Rida W, Priddy FH, Pung P, Carrow E, Laufer DS, Lehrman JK, Boaz M, Tarragona-Fiol T, Miiro G, Birungi J, Pozniak A, McPhee DA, Manigart O, Karita E, Inwoley A, Jaoko W, Dehovitz J, Bekker LG, Pitisuttithum P, Paris R, Walker LM, Poignard P, Wrin T, Fast PE, Burton DR, Koff WC. Human immunodeficiency virus type 1 elite neutralizers: individuals with broad and potent neutralizing activity identified by using a high-throughput neutralization assay together with an analytical selection algorithm. J Virol. 2009 Jul;83(14):7337-48. doi: 10.1128/JVI.00110-09. Epub 2009 May 13.
6.Li M, Gao F, Mascola JR, Stamatatos L, Polonis VR, Koutsoukos M, Voss G, Goepfert P, Gilbert P, Greene KM, Bilska M, Kothe DL, Salazar-Gonzalez JF, Wei X, Decker JM, Hahn BH, Montefiori DC. 2005. Human immunodeficiency virus type 1 env clones from acute and early subtype B infections for standardized assessments of vaccine-elicited neutralizing antibodies. J Virol 79:10108 –10125. https://doi.org/10.1128/JVI.79.16.10108-10125.2005.
7.Keele BF, Giorgi EE, Salazar-Gonzalez JF, Decker JM, Pham KT, Salazar MG, Sun C, Grayson T, Wang S, Li H, Wei X, Jiang C, Kirchherr JL, Gao F, Anderson JA, Ping L-H, Swanstrom R, Tomaras GD, Blattner WA, Goepfert PA, Kilby JM, Saag MS, Delwart EL, Busch MP, Cohen MS, Montefiori DC, Haynes BF, Gaschen B, Athreya GS, Lee HY, Wood N, Seoighe C, Perelson AS, Bhattacharya T, Korber BT, Hahn BH, Shaw GM. 2008. Identification and characterization of transmitted and early founder virus envelopes in primary HIV-1 infection. Proc Natl Acad Sci U S A 105:7552–7557. https://doi.org/10.1073/pnas.0802203105.
8.Rademeyer C, Korber B, Seaman MS, Giorgi EE, Thebus R, Robles A, Sheward DJ, Wagh K, Garrity J, Carey BR, Gao H, Greene KM, Tang H, Bandawe GP, Marais JC, Diphoko TE, Hraber P, Tumba N, Moore PL, Gray GE, Kublin J, McElrath MJ, Vermeulen M, Middelkoop K, Bekker L-G, Hoelscher M, Maboko L, Makhema J, Robb ML, Abdool Karim S, Abdool Karim Q, Kim JH, Hahn BH, Gao F, Swanstrom R, Morris L, Montefiori DC, Williamson C. 2016. Features of recently transmitted HIV-1 clade C viruses that impact antibody recognition: implications for active and passive immunization. PLoS Pathog 12:e1005742. https://doi.org/10.1371/journal.ppat.1005742.
Nitesh Mishra
AIIMS, New Delhi
How to teach a robot to do brain surgery?
How to teach a robot to do brain surgery?
It takes about 5 minutes to allow for blood flow to the brain after removing a temporary clip during surgery for a cerebral aneurysm. It is about the same time taken to relieve a cramp in the leg.
Abstract
How to teach a robot to do brain surgery?
It takes about 5 minutes to allow for blood flow to the brain after removing a temporary clip during surgery for a cerebral aneurysm. It is about the same time taken to relieve a cramp in the leg. It is also the time taken for my tremors to calm down before the all-important step of aneurysm clipping. Surgery on the brain is thus a very human task involving a deadly cocktail of Adrenaline and Cortisol.
But can a robot perform brain surgery? The question forms the basis of work conducted jointly between NIMHANS, a tertiary care hospital for diseases of the nervous system and IIIT-B, an institute with expertise in engineering. Surgical robots available at present are slaves and the surgeon their master. The robot mimics the surgeons' hands, albeit with greater accuracy and no tremor.
The manipulation of volume and management of time are vital skill sets of the neurosurgeon. Structures are modified, joined, removed, destroyed or aligned. Thus tumours are removed and bleeding blood vessels destroyed. All of these volumes are visualised using an operating microscope and operated upon using micro instruments.
The views obtained during brain surgery are different from different perspectives for a given target volume. The target volume for surgery is determined based on medical imaging tools such as a CT scan, MRI scan and angiography. The visualised volume can consist of both normal and abnormal tissues. A brain tumour can be thought of as an abnormal volume contained within normal brain volume. Each surgical step can be thought of as a function call implemented on the visualised target volume. Just like a function key is used to implement a computer task, a surgical tool is used to perform a surgical step. The manipulated tissue reacts: tumours bleed, vessels contract. These tissue actions, in turn, evoke surgeon reactions. Every surgeon responds uniquely to a given surgical event. Each action-reaction sequence can be labelled a state of the surgical field. The state here refers to an entity with attributes such as anatomical volume, physiological parameters such as heart rate, the extent of blood loss at that instant. An action performed using surgical tools results in a new state. A surgeon does not compute every outcome in a given ‘state’. Creating a model which envisions every surgical state and corresponding reactions is not feasible. In practice, surgeons evaluate actions in terms of risk. Actions of the surgeon are target-oriented and are sequentially performed step-wise to achieve the surgical goal. Each action thus acquires a risk value. The surgeon evaluates the risk and decides on the course of action. The entire surgical procedure can be thought of individual small action steps performed in sequence. Each step thus changes an existing state of surgery into a new surgical state. A small amount of risk is taken in reaching every new state. Risk has an anatomical or static component and execution or dynamic component. Similar to risk, there is also a reward component in moving from a state to a new state. Tumour volume decreases as more and more tissue is removed. A cost is incurred while traversing from one state to the next. As the time taken to remove a tumour is increased, duration of time when blood loss occurs increases, which are an example of the cost incurred.
A Markov Decision Process is a mathematical method to model real-life situations. The technique utilises entities such as states, actions, probabilities and rewards to model stochastic processes. Surgery can be defined as a set of stochastic actions which are executed by the surgeon. The concepts outlined above are in alignment with the requirements of a Markov Decision Process. The reward and cost are factors which are the outcomes of progressing from one surgical state to the next and can be generalised to the entire surgical event. It is thus possible to model a complete surgery using a mathematical method like the Markov Decision Process.
The work presented here attempts to apply knowledge from diverse fields such as artificial intelligence and robotics to advance surgery on the brain. If I succeed in this endeavour, I foresee myself as my “assistant’s” assistant in the future! Eventually, I may even lose my job.
Vikas Vazhayil
IIIT Bangalore
Selected Candidates
How proteins function and communicate in a cell without a brain
Talk your thesis /Title of the talk: How proteins function and communicate in a cell without a brain. Title of Ph.D. thesis: Deciphering the mode of regulation and understanding protein-protein interactions of human HtrA serine proteases.
Abstract
Talk your thesis /Title of the talk: How proteins function and communicate in a cell without a brain.
Title of Ph.D. thesis: Deciphering the mode of regulation and understanding protein-protein interactions of human HtrA serine proteases.
Cellular proteins and enzymes perform a wide variety of functions in a cell. Almost one-third of all proteases can be classified as serine proteases, named for the nucleophilic Ser residue at the active site[1]. High temperature requirement protein A (HtrA) family proteases are highly conserved oligomeric serine proteases present in prokaryotes as well as eukaryotes and perform diversified functions[2]. In E. coli these were initially identified as heat shock-induced envelope-associated serine proteases[3]. Alterations or mutations in these proteases may lead to various diseases in humans like neurodegenerative, neuromuscular disorders, arthritis, age-related macular degeneration, cancer and the pregnancy-specific disease preeclampsia[4]–[8]. Although maintenance of protein quality is major function they also perform various other functions like unfolded protein response, cell growth, homeostasis, apoptosis, molecular chaperones and proteases[9]–[12]. There are four human homologues of HtrA have been identified: HtrA1, HtrA2/Omi, HtrA3 and HtrA4. In case of mammalian HtrA proteins, in spite of having complexity and variations in their structure and functions, all of them share a basic domain organization which consists of N-terminal sequence, serine protease domain (SPD) and PDZ domain (postsynaptic density of 95 kDa, disk large, and zonula-occludens 1 domain). The PDZ domain is responsible for protein-protein interactions which bind specifically to the natural interacting partners and substrate in the cell to regulate various functions. N-terminal region helps in the formation of functional oligomers which are mostly trimeric in nature.
HtrA2 is a nuclear-encoded serine protease that performs several critical cellular functions in a coordinated fashion. Although, HtrA2 has primarily been identified as an IAP-binding proapoptotic protein[13], its other functions such as caspase-independent induction of apoptosis and serine protease activity are poorly characterized. To delineate the structural correlates of HtrA2 activation, substrate recognition and specificity, comprehensive binding studies with its interacting partners is necessary. We dissected the molecular mechanism of HtrA2 with one of its interacting partner cum tumor suppressor protein GRIM-19 (Gene-associated with retinoid-IFN-induced mortality 19) and provided the comprehensive binding analysis of HtrA2-GRIM-19 interaction [14]. Our binding studies demonstrated that serine protease domain of HtrA2 interacts with both full length as well as cell death inducing domain region of GRIM-19. Enzymology studies with GRIM-19 suggest that it is an allosteric activator of HtrA2 as it enhances the protease activity several fold. This might lead to activation of HtrA2 with the cleavage of several critical cellular proteins thus triggering apoptosis. Furthermore, our substrate specificity studies with GRIM-19 highlight that HtrA2 has broad substrate specificity toward the residues in the vicinity of its cleavage sites. We hypothesize that this broad specificity might be required for cleaving a variety of substrates by HtrA2 that commensurate very well with its diverse physiological functions. Proteolytic activity of HtrA2 has been reported to be critical in inducing apoptosis in prostate and ovarian cancer cells in presence of stress inducing agents[15]. These studies show the possibility of targeting HtrA2 in cancer therapy[16]. Our advancement in understanding toward HtrA2 mechanism of action will help in developing tailored allosteric effectors that might enhance the proteolytic activity of HtrA2 towards its substrates.
HtrA4 is a secretary serine protease whose expression is up-regulated in pre-eclampsia (PE) and hence is a possible biomarker of PE[17]. It has also been altered in cancers such as glioblastoma, breast carcinoma, and prostate cancer making it an emerging therapeutic target[18]. Among the human HtrAs, HtrA4 is the least characterized protease pertaining to both structure and its functions. Although the members of human HtrA family share a significant structural and functional conservation, subtle structural changes have been associated with certain distinct functional requirements. Therefore, intricate dissection of HtrA4 structural and functional properties becomes imperative to understand its role in various biological and patho-physiological processes. Using inter-disciplinary approaches including in silico, bio-chemical and biophysical studies, we have done a domain-wise dissection of HtrA4 to delineate the roles of the domains in regulating oligomerization, stability, protease activity, and specificity. Our findings distinctly demonstrate the importance of the N-terminal region in oligomerization, stability and hence the formation of a functional enzyme. Insilico structural comparison of HtrA4 with other human HtrAs, enzymology studies and cleavage assays with generic substrate (β-casein) and X-linked inhibitor of apoptosis protein (XIAP) show overall structural conservation, mechanism of cleavage (Hold-bite-rebind) and allosteric mode of protease activation, which suggest functional redundancy within this protease family. However, significantly lower protease activity as compared with HtrA2 indicates an additional mode of regulation of the protease activity in the cellular milieu. Overall, these studies provide first-hand information on HtrA4 and its inter-action with antiapoptotic XIAP thus implicating its involvement in the apoptotic pathway.
[1]L. Hedstrom, “Serine Protease Mechanism and Specificity,” 2002.
[2]M. J. Pallen and B. W. Wren, “The HtrA family of serine proteases,” Mol. Microbiol., vol. 26, no. 2, pp. 209–221, Oct. 1997.
[3]C. Spiess, A. Beil, and M. Ehrmann, “A temperature-dependent switch from chaperone to protease in a widely conserved heat shock protein.,” Cell, vol. 97, no. 3, pp. 339–47, Apr. 1999.
[4]J. M. Milner, A. Patel, and A. D. Rowan, “Emerging roles of serine proteinases in tissue turnover in arthritis,” Arthritis Rheum., vol. 58, no. 12, pp. 3644–3656, Dec. 2008.
[5]L. Vande Walle, M. Lamkanfi, and P. Vandenabeele, “The mitochondrial serine protease HtrA2/Omi: an overview,” Cell Death Differ., vol. 15, no. 3, pp. 453–460, Mar. 2008.
[6]H. R. Coleman, C.-C. Chan, F. L. Ferris, and E. Y. Chew, “Age-related macular degeneration,” Lancet, vol. 372, no. 9652, pp. 1835–1845, Nov. 2008.
[7]K. Hara et al., “Association of HTRA1 Mutations and Familial Ischemic Cerebral Small-Vessel Disease,” N. Engl. J. Med., vol. 360, no. 17, pp. 1729–1739, Apr. 2009.
[8]J. Chien, M. Campioni, V. Shridhar, and A. Baldi, “HtrA serine proteases as potential therapeutic targets in cancer.,” Curr. Cancer Drug Targets, vol. 9, no. 4, pp. 451–68, Jun. 2009.
[9]T. Clausen, C. Southan, and M. Ehrmann, “The HtrA family of proteases: implications for protein composition and cell fate.,” Mol. Cell, vol. 10, no. 3, pp. 443–55, Sep. 2002.
[10]P. F. Huesgen, H. Schuhmann, and I. Adamska, “Deg/HtrA proteases as components of a network for photosystem II quality control in chloroplasts and cyanobacteria,” Res. Microbiol., vol. 160, no. 9, pp. 726–732, Nov. 2009.
[11]J. Chien et al., “Serine protease HtrA1 associates with microtubules and inhibits cell migration.,” Mol. Cell. Biol., vol. 29, no. 15, pp. 4177–87, Aug. 2009.
[12]T. Krojer, J. Sawa, E. Schäfer, H. R. Saibil, M. Ehrmann, and T. Clausen, “Structural basis for the regulated protease and chaperone function of DegP,” Nature, vol. 453, no. 7197, pp. 885–890, Jun. 2008.
[13]A. M. Verhagen et al., “HtrA2 Promotes Cell Death through Its Serine Protease Activity and Its Ability to Antagonize Inhibitor of Apoptosis Proteins,” J. Biol. Chem., vol. 277, no. 1, pp. 445–454, Jan. 2002.
[14]X. Ma, S. Kalakonda, S. M. Srinivasula, S. P. Reddy, L. C. Platanias, and D. V Kalvakolanu, “GRIM-19 associates with the serine protease HtrA2 for promoting cell death,” Oncogene, vol. 26, no. 33, pp. 4842–4849, Jul. 2007.
[15]S. Yamauchi et al., “p53-mediated activation of the mitochondrial protease HtrA2/Omi prevents cell invasion,” J. Cell Biol., vol. 204, no. 7, pp. 1191–1207, Mar. 2014.
[16]J. Chien, M. Campioni, V. Shridhar, and A. Baldi, “HtrA serine proteases as potential therapeutic targets in cancer.,” Curr. Cancer Drug Targets, vol. 9, no. 4, pp. 451–68, Jun. 2009.
[17]C. Liu et al., “Elevated HTRA1 and HTRA4 in severe preeclampsia and their roles in trophoblast functions,” Mol. Med. Rep., vol. 18, no. 3, pp. 2937–2944, Jul. 2018.
[18]D. Zurawa-Janicka, J. Skorko-Glonek, and B. Lipinska, “HtrA proteins as targets in therapy of cancer and other diseases,” Expert Opin. Ther. Targets, vol. 14, no. 7, pp. 665–679, Jul. 2010.
Raghupathi K
Music Information Retrieval
This thesis can be placed in the broader field of Music Information Retrieval
(MIR). MIR refers to a huge set of strategies, software and tools through which
computers can analyse and predict interesting patterns from audio data.
Abstract
This thesis can be placed in the broader field of Music Information Retrieval
(MIR). MIR refers to a huge set of strategies, software and tools through which
computers can analyse and predict interesting patterns from audio data. It is
a diverse and multidisciplinary field, encompassing fields like signal processing,
machine learning, musicology and music theory, to name a few.
Methods of dimensionality reduction are widely used in data mining and machine
learning. These help in reducing the complexity of the classification/clustering
algorithms etc, used to process the data. They also help in studying some use-
ful statistical properties of the dataset. In this Master’s Thesis, a personalized
music collection is taken and audio features are extracted from the songs, by
using the mel spectrogram. A music tensor is built from these features. Then,
two approaches to unfold the tensor and convert it into a 2-way data matrix
are studied. After unfolding the tensor, dimensionality reduction techniques like
Principal Components Analyis (PCA) and classic metric Multidimensional Scal-
ing (MDS) are applied. Unfolding the tensor and performing either MDS or PCA
is equivalent to performing Multiway Principal Component Analysis (MPCA).
A third method Multilevel Simultaneous Component Analysis (MLSCA), which
builds a composite model for each song is also applied.
The number of components to retain are obtained by hold-out validation. The
fitness of each of these models were evaluated with the T-squared and Q statistic, and
compared with each other. The aim of this thesis is to produce a dimensionality
reduction which can be used for further MIR tasks like better clustering of data
with respect to e.g. artists / genres.
References:
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Ajay Ramaseshan
Measures for judgement of melodic similarity
Indian art music is predominantly an oral tradition with pedagogy involving the oral transmission of raga lessons. There exist text resources for musicology, wherein the lexicon finds its place in a rather prescriptive manner.
Abstract
Indian art music is predominantly an oral tradition with pedagogy involving the oral transmission of raga lessons. There exist text resources for musicology, wherein the lexicon finds its place in a rather prescriptive manner. Raga performance allows for considerable flexibility in the interpretation of the raga grammar in order to incorporate elements of creativity via improvisation. It is therefore of interest to understand how the musical concepts are manifested in performance, and how the artiste improvises i.e. uses the stock musicological knowledge in “new” ways, while carefully maintaining the distinctiveness of each raga in the ears of trained listeners. Alongside addressing the issue of subjectivity, scalability, and reproducibility in musicological research, this work proposes novel methods for relevant music information retrieval (MIR) applications like rich transcription, melody segmentation, motif spotting, raga recognition. While a general engineering approach is to optimize certain evaluation metrics, we aimed to ensure that our findings are informed by musicological knowledge and human judgment. To achieve this, our approach is two-fold: computational modeling of the melody on a sizable, representative corpus; then validating the models through behavioral experiments towards understanding the learned schema by trained musicians.
We propose computational representations that robustly capture the particular melodic features of the raga while being sensitive enough to the differences between ragas tested within a sizable, representative music corpus. To make a good foundation for tuning of hyper-parameters, we exploit the notion of “allied ragas” that use the same tonal material but differ in their order, hierarchy, and phraseology. Our results show that computational representations of distributional and structural information in the melody, combined with suitable distance measures give insights about how the aspect of raga distinctiveness is manifested in practice over different time scales by creative performers. Finally, motivated by the parallels between musical structure and prosodic structure in speech, we present listening experiments that explore musicians’ perception of ecologically valid synthesized variants of a raga-characteristic phrase. Our findings suggest that trained musicians clearly demonstrate elements of categorical perception in the context of the technical boundary of a raga.
Our analyses of performance audio use computational models to achieve an understanding of: (i) how the mandatory grammar is satisfied in performance, (ii) whether there are other consistent practices observed for a raga apart from what is specified by the grammar, and (iii) how the artist improvises i.e. uses the stock knowledge of the raga lexicon/grammar in ``new'' ways. We choose well-known allied raga-pairs for an empirical study of computational representations for the distinctive attributes of tonal hierarchy and melodic shapes. Raga notes, their relative salience, and intonation are supported by the concert-level continuous pitch histograms and discrete svara histograms. The frequency of occurrence of characteristic motifs is supported by relative counts of the characteristic motifs within performances. Melodic shape measurements with regard to duration are consistent with specified aspects, if any, of melodic shape, i.e. the variability is found to be least where the raga lexicon/grammar has a firm prescription. Elsewhere, the variability is somewhat predictable from context information. We also got certain insights on similarities and differences across performances of a raga. The more ``specified'' a raga, the less variable it is across performances. At least one prominent aspect of ``improvisation"" is the course of svara-level exploration as the concert progresses in time, i.e. what is ``spontaneous'' is the decision to use a particular phrase or sequence of phrases at a given moment in the performance. Experienced artists use melodic phrases in flexible ways without violating the prescriptions. ``Ungrammaticality'' refers to extending the flexibility so far as to tread on another raga. We observe that this is avoided by eminent performers.
Finally, we are excited to note that all of the above concerns boil down to the neuropsychological aspects of melodic similarity, i.e., what do humans ``understand'' by ``similarity''. May it be the effect of training in music perception, or the process of ``gist''-ing music information in human memory, or storing a representative/exemplar ``template'' for a melodic phrase in human brain, or modeling musical ``knowledge''; study of cognitive musicology is the best way out. Thus, given the resources (paradigms like music technology, cognitive musicology, music performance, etc.) of interdisciplinary research, though limited, we pursue our humble endeavor towards finding a computational measure for adequately modeling human judgment of melodic similarity.
The signed declaration form has the publication list in the following pages. The pdf documents are available online on the Google Scholar profile: https://scholar.google.com/citations?user=uhYmMbgAAAAJ
Kaustav Kanti Ganguli
Organic liquid for quick detection of metal
Metal ions come with a lot of harmful activity both ways excessive increase and decrease. Detection of metal ions is an important area of research. One of the major problems that our young generation faces is Baldness or thinning of hair.
Abstract
BALD or HAIRY! Detect before Using
Introduction
Metal ions come with a lot of harmful activity both ways excessive increase and decrease. Detection of metal ions is an important area of research. One of the major problems that our young generation faces is Baldness or thinning of hair. This is true especially; Groundwater contains plenty of minerals like iron and magnesium. These minerals make your hair lustreless and eventually make your hair-thin. This kind of water is mostly found in rural areas where there are hardly any freshwater sources.
How will my innovation address the problem?
Through literature, we can find past research work dealing with detecting metal ions in the water sample. Most of them use expensive methodologies, costly material, and a huge time-consuming procedure. Besides, they use expensive nanoparticles like gold, toxic metals like cadmium. On the contrary, I am making Lanthanide-doped organic ligand capped CaF2 nanoparticle for detecting Fe3+ ion in water which will be cheap, easy to make and give quick detection
Why fluorescence-based detection?
Fluorescence-based detection is very beneficial than other detection techniques which are time-consuming and very much expensive. For example, the electrochemical method, mass-spectrophotometer, HPLC (High-performance liquid chromatography) cannot be moved due to lack of portability. On the contrary, fluorescence-based-sensing gave better selectivity, short response time. Besides, the sample preparation is fairly easier.
Why use Lanthanide-doped nanoparticle?
The nanoparticles doped with Lanthanide gave sharp emission. The main interest in Ln labels resides in electronic properties due to f-f transition. Additionally, the 4f orbital, being diffused is shielded from the environment(shielding effect) by the filled 5s and 5p orbitals. This results in very weak ligand field interactions, so giving no perturbation in the luminescence spectral transitions.
The result of the forbidden transition is the low probability of spontaneous emission and longer excited-state lifetime. Furthermore, the stokes shift is also high. Lanthanide doped nanomaterials are promising because of the intra 4f*4f transitions from the Ln3+ ions are quite sharp with FWHM in the range of 5nm. They exhibit large Stokes-shift which reduces any optical interference from other molecules and long excited-state lifetime typically in the millisecond to microsecond time scale allowing efficient excited-state processes.
Also, the long lifetime can be very selective and easily differentiate the contribution from the real optical signals from fluorescence from any other impurity species. Besides, Ln-doped nanoparticles are very good spectral converters allowing tuning of the optical properties.
Can you tell some past works?
In 2016 R.Dutta and A.Kumar have made Amine-Modified Cadmium Sulfide Quantum Dots nanoparticle which shows luminescence quenching in the presence of uranyl ion.
V.Mahalingam and co-workers have presented the lanthanide-doped nanoparticle for Cu2+ detection. They used Cerium is the sensitizer, Terbium is the emitter and polyacrylic acid as the capping ligand. Upon excitation, the sensitizer reaches a first singlet excited state, and it is generally assumed that the energy is transferred to the lanthanides excited state (Ln*). After this step emission happens and we can see quintessential peaks for Tb.
Later in 2019 V.Mahalingam and his co-workers have shown sensing of nitro-aromatic pollutants utilizing mercaptobenzoic acid as capping ligand as well as a sensitizer. Due to this the analyte and the Ln3+ ¬¬¬¬¬¬¬ions are really close giving better detection limits.
Speak about the mechanism?
The emission mechanism is through antenna effect. Upon excitation, the ligand reaches a first singlet excited state, and it is generally assumed that the energy is first transferred to a ligand-centered triplet state (T1) by intersystem crossing and from there to the
Where do you stand?
I am further utilizing the CaF2 and capping it with different organic ligand with selective sensing of toxic metals like arsenic, cadmium, iron.
The organic ligand can be modified so that it can serve
i)As a capping agent
ii)As a sensitizer
iii)Selective interaction with the desirable metal ion.
I synthesized nanoparticle which shows selectivity towards Fe3+ ion and not interacting with other ions even Fe2+. About this, I will be presenting in India-Science-Fest.
What will be the future?
With this kind of cheap nanoparticle, we can create a portable kit. For that first, the nanoparticles have to be surface-immobilized into cellulose sheets. Then just by using one UV light and smartphone camera one can know in a water sample how much percentage of the toxic material is present. It can be useful for farmers too; they also utilize the kit before using water in his field. Not only this but if this is legalised and manufactured by the government, the socio-economic pattern of India will change.
Reference:
i) (1) Adusumalli, V. N. K. B.; Koppisetti, H. V. S. R. M.; Madhukar, N.; Mahalingam, V. 4-Mercaptobenzoic Acid Capped terbium(III)-Doped CaF2 Nanocrystals: A Fluorescent Probe for Nitroaromatic Pollutants. Microchimica Acta 2019, 186 (6). https://doi.org/10.1007/s00604-019-3484-8.
ii) (1) Sarkar, S.; Chatti, M.; Adusumalli, V. N. K. B.; Mahalingam, V. Highly Selective and Sensitive Detection of Cu2+ Ions Using Ce(III)/Tb(III)-Doped SrF2 Nanocrystals as Fluorescent Probe. ACS Applied Materials & Interfaces 2015, 7 (46), 25702–25708. https://doi.org/10.1021/acsami.5b06730.
Nabojit Kar
Nanotechnology for water purification
With the increase in population and industrialization in the world, there has been a scarcity of pure drinking water. There is an urgent need to promote a new cost-effective technique for purifying the water.
Abstract
With the increase in population and industrialization in the world, there has been a scarcity of pure drinking water. There is an urgent need to promote a new cost-effective technique for purifying the water. Nanotechnology provides a unique platform for tuning materials with unique properties that can purify water. We in this article focused on the use of a novel high flux filtration hybrid membrane system. The membrane system consists of a three-layer composite with hierarchical structures, i.e. a highly porous hydrophilic material coated with a top layer, an electrospun nanofibrous barrier layer in the middle and a nonwoven fibrous web to support the bottom layer to provide high tensile strength.
Keywords: Electrospinning technique; Hybrid membrane; Nanomaterials; Porous nanofibers.
https://www.researchgate.net/profile/Manish_Yadav28/research
Manish Kumar
PYP finalist and ISF fellow, Arush Gupta, gets felicitated at India Science Festival, 2020
Winners of Perform your Project - ISMO 2021
Atharva Valanju
Siddhant Thawrani
Shiv Sagar
How innovatively can you present science? Talk, demonstrate, dance, sing, draw or act out a solid scientific concept, the floor is all yours! A competition for all science enthusiasts to unleash their creativity and present a science project or concept in the most innovative manner possible! 5 finalists will be selected through a competitive process judged by a jury.
Get mentored by scientists from prestigious universities across the world
Win exciting cash prizes !
Present your work to a global audience.
These 5 finalists, or the ISF Fellows, will be mentored by our panel and will consequently battle it out to win the top 3 positions!
Eligibility: Anyone who has worked on a science project in senior school, final year of college or as a part of their personal endeavor.
UPDATED DEADLINE FOR SUBMISSIONS: 15th October, 2020.
Prizes: Cash prize along with the coveted title of becoming an ISF Fellow! 1st position: $400 2nd position: $250 3rd position: $150
Guidelines: Click here to download the detailed guidelines.
Registrations are closed now. If you've already registered, click here to submit your entry
Need some inspiration? Here are our Finalists from 2020.
Voice controlled robotic arm
A robotic hand is reprogrammable multifunctional model designed to perform the various task via voice command, with similar functions to a human hand. The links of such a manipulator are connected by joints allowing the gripping motion.
Abstract
A robotic hand is reprogrammable multifunctional model designed to perform the various task via voice command, with similar functions to a human hand. The links of such a manipulator are connected by joints allowing the gripping motion.
Conclusion:
1. The objective of this project has been achieved which is to develop hardware and software for a robotic palm which is voice-controlled.
2. From the observations that have been made, it clearly shows that its movement is precise, accurate, and is easy to control and user-friendly.
3. The robotic palm has been developed successfully as the movement of the palm is similar to human palm and is reprogrammable.
Future scope
1. In the medical field, if the surgeon is not present at the place of surgery, he could use this technology and he/she would be able to do surgery from long distance with a voice command.
2. In defence, it will be very useful to tackle situations related to diffusing an explosive material without any loss of an individual and can be controlled only with the help of voice command over along range distance.
Ankit Santosh Gupta
Pune
Duo-vent: AI-enabled Smart ventilation system
In India there are around 1 million cases of interstitial lung diseases in farmers due to bacteria, moulds, fungi in hay or other grains also the pesticides and insecticides used in agriculture.
Abstract
In India there are around 1 million cases of interstitial lung diseases in farmers due to bacteria, moulds, fungi in hay or other grains also the pesticides and insecticides used in agriculture. According to CBHI 2017-18 data, in India there are around 41.5 million acute respiratory illness cases per year. These conditions lead to scarring of the lung and requires extra oxygen supply as treatment to avoid shortness of breath. Also smoking bidi and cigarettes is more popular in rural elderly men which is the prime reason for the high number of lung cancer in Rural India.
Mechanical ventilation is suggested to elderly respiratory patients suffering from these infections, to enhance gas exchange in the lungs. Geriatric Patients with impaired respiratory function usually have pulmonary consolidation. Consolidation occurs when the air that usually fills the alveoli in the lungs is replaced with some bacterial/chemical liquid or solid cells during cancer. Current treatment protocols for the treatment of patients suffering from respiratory failure with consolidated lung rely on conventional uniform pressure-controlled ventilators. These ventilators provide positive pressure to both the lungs to open up the alveoli and enhance the gas exchange in the lungs. This method of treatment using conventional mechanical ventilators are susceptible to a multitude of potentially fatal conditions such as alveolar damage in the non-diseased lung, transfer of bacterial infection like pneumonia from the infected lung to non-infected one and reduction in breathing capacities as the alveoli lose their elasticity. Also, we know that ICU is the most expensive and resource-demanding unit when compared to all the other units in the Rural hospital, they alone utilize about 20% of all hospital costs. The daily total cost in Rural area for a non-ventilated patient is Rs. 6585 ± 932 for medicines etc., whereas that for a ventilated patient is Rs. 12,429 ± 9720. In Rural Hospitals, ICU ventilators are used for approximately 3/10 of admitted patients with the rest 7/10 being treated at normal breathing without mechanical support due to lack of ventilators or unable to afford for ventilator cost in rural hospitals. This increases the hospitalization days and adds to the shortage of ventilator for the others in the waiting list in the rural area. After performing a thorough market analysis and interacting with diverse stakeholders in Rural area I identified the top reasons for lack of ventilators: In Rural hospitals, the high cost of ventilation comes from the high cost of the equipment and the enormous amount of money which goes for service and maintenance. Both add to the high ventilation cost charged on the patient and it makes them unavailable in many hospitals, it is also the reason why mechanical ventilation is unaffordable for an average Indian.
To solve this problem I have developed an AI-enabled Smart and Cost-effective ventilation system called 'Duo-vent’ for elderly patients in ICU with respiratory illnesses. This innovation will provide lung isolation and independently controlled ventilation to each lung for unilateral lung consolidation or in conditions like ARDS where one lung is infected more than the other. This method of treatment will avoid ventilator-induced lung injury for the patients. The AI algorithm used in this product will detect each breath of the patient and will send out alerts using the IoT enabled smart technology during an emergency. The novel recovery rate monitoring used in the device will help the doctors to efficiently wean the patient from the ventilator. Each breath of the patient will be recorded and transferred via Wireless connectivity to enable telemedicine support. This feature enables caretakers to monitor patients remotely and proactively, allowing for fast and informed clinical decisions including early intervention, which can help avoid unnecessary readmissions and lower cost of care. Using the unique profit-sharing business model, I intend to provide service and maintenance at a minimal cost to the hospital. Enhanced treatment of the patient using Duo-Vent will result in decreased hospitalization time and it will reduce the cost burden by 80% on the patient.
Bibliography
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Rajesh Thangavel Yadav
Hyderabad
Controlling someone else's arm using your brain
Brain is an amazing and complex organ but we hardly know anything about brain because we are never taught anything about neuroscience in schools and colleges. The reason being that the tools and equipment’s involved is very expensive.
Abstract
Brain is an amazing and complex organ but we hardly know anything about brain because we are never taught anything about neuroscience in schools and colleges. The reason being that the tools and equipment’s involved is very expensive. And the interesting part is that almost 20% people in the world are suffering from some or the other neurological disorder. So, we have we have come up with this project where we can learn some basic things about brain.
Have you ever thought of controlling people around you? Yes, at some point of time we might have thought of having a technology which could help us to control people around us either for some useful thing (to help people with claw hands) or just for fun. Now the interesting thing is that such technology actually exists with the help of which we can control humans. Our project is about controlling humans and taking away their free will.
So, it consists of an Arduino, amplifier, tens unit and electrodes with the help of which we can control human’s activity. Firstly, we paste electrode to the controller’s nerve and take the electric signals from his hand and then with the help of amplifier we amplify the value because the electric signal obtained is very less. This electric signal taken as output from the person is then processed with the help of Arduino IDE into digital form. After coding the values into digital form, it cannot be understood by the body of the person to be controlled because human body does not understand digital code. So now we use tens unit to inject the signal into the controller and control his hand. The value processed in Arduino is given to the tens unit and tens unit injects this signal into the ulnar nerve of the controller (ulnar nerve is present right at the back side of the hand, we use it because it helps in controlling the middle finger, ring finger and the little finger). Now when the controller moves his hand then the controlled person automatically starts moving his hand without his permission i.e., we can say that we have taken away his free will.
This is possible because when we think of moving any of our body parts then our brain sends some electrical signals to our body parts (mainly cortex in our brain is responsible for sending all the signals to ou r body). We take these signals from the body parts and amplify the signal and inject to some other person whom we want to control. This experiment is only possible till when the controller is thinking. If he is not using his brain and somebody tries to move his hand then it will not work because electrical signals are not generated.
This can be use in two ways
• Human to human interface
• Human to machine interface
The main advantage of the project is that it can prove to be very useful in the field of medical. This can help people with claw hands or if someone is paralytic. It can be fitted to some healthy person and he can control the person with disability so that he can do his work (such disease usually occurs because the electric signals sent from brain is not processed by the body parts)
Anubhav Mishra
Kanpur
Flywheel: Battery less UPS System
Currently the concept of fly wheel energy storage is more popular in the area of aero space and electrical vehicles requiring short term and high power. This concept is gaining popularity in the area of power quality and stability since the life of fly wheel
Abstract
Currently the concept of fly wheel energy storage is more popular in the area of aero space and electrical vehicles requiring short term and high power. This concept is gaining popularity in the area of power quality and stability since the life of fly wheel energy storage system is high with good round trip efficiency and zero depreciation in capacity. The system also needs less maintenance compared to battery storage systems. Also the concept of generation form renewable energy sources makes an electrical load independent of conventional grid.
The need for battery less UPS system arises since batteries used in the conventional UPS system have less life time and a major concern of environmental pollution. For any short term power requirements, a Kinetic Energy storage system such as fly wheel energy storage can be effectively utilized instead of the electrochemical batteries. Hence the combination of solar PV based power generation along with a battery less online power conditioning system to supply a critical load is the proposed in this scheme. The entire battery less UPS system is controlled using resonant dc-dc converter and controller. Here a mechanical fly wheel which stores kinetic energy in it acts similar to the battery in providing short term power requirement to the connected load during the power outages in order to improve the reliability of the system.
The system is so proposed that it is normally independent of the grid since a photovoltaic system will be used for power generation. Thus the combination of solar power and flywheel make this work purely environment friendly due to absence of batteries and a fore runner for the society to go in for production and utilization of green energy.
The main players in this proposed configuration are the Permanent Magnet Brushless DC (PMBLDC) motor and its driver used in fly wheel based energy storage system and the resonant dc-dc converter.
Sivaranjani S
Chennai
KnightCryption: Encryption algorithm derived from chess, math and sanksrit poetry
“KnightCryption” is a highly efficient Image Encryption Algorithm which I have derived using the interesting concepts from game of Chess, Math, poetry from Ancient Sanskrit Shloka and of course my favorite language “Python “and OpenCV.
Abstract
“KnightCryption” is a highly efficient Image Encryption Algorithm which I have derived using the interesting concepts from game of Chess, Math, poetry from Ancient Sanskrit Shloka and of course my favorite language “Python “and OpenCV. This algorithm ensures that it can be applied on images of varied resolutions and user can flexibly define the levels of encryption needed. The algorithm ensures it has very high Key space, high Key Sensitivity, high uniform Histogram of the encrypted image.
The algorithm takes inspiration from the work of Ancient Sanskrit Poet named Rudrata, where in a simple Sanskrit Shloka he described Knights tour of Chess in poetic and cryptic manner. Inspired by that, I have put together this Image Encryption and Decryption Algorithm in Python where I use a complex 16 by16 Chess board Knight tour solution to encrypt the image, where each block is further encrypted in 16 by 16, to ensure secrecy. Then I change the colors to further encrypt the image.
in today modern world it has great application, picture or image cryptography by dividing the picture in squares and using the Knight tour to encrypt is practically used and the decryption depends on knowledge of tour solution. In general, due to vast number, enormous number of possible Knight tour it is very difficult to obtain the decryption key for any unauthorized person.
Arush Gupta
Pune
Tashan Mehta, author of the sci-fi novel 'The Liar's Weave', speaks at India Science Fest, Jan 2020.
Winners of Science Writing - ISMO 2021
Manu Priyadarshi
Melissa Maize
Kuljeet Kaur
SPIN YOUR SCIENCE : Tell a tech-tale, Spin a sci-verse Fancy yourself to be a budding Isaac Asimov? Fascinated by the stories that bring together science and fiction? Do your favorite movies and books run on the lines of Avatar, Interstellar, Star Wars or Star Trek?
Calling all sci-fi buffs! Here's a competition to appeal to the curious writer within you!
Spin a short science story or poem. A sprinkle of creativity, a dash of innovation, merge a science topic with your imagination!
We will put you on a global stage presenting to hundreds of people.
Get mentored by acclaimed science fiction writers.
Read your story out to global online audience at ISMO 2021.
Get your work published on our website, win exciting cash prizes!.
Top 5 finalists, or the ISF Fellows, get to attend an exclusive workshop where they will be mentored by our jury members. They will consequently battle it out to win the top 3 positions!
Eligibility: This competition is open for anyone aged 17 and above.
UPDATED DEADLINE FOR SUBMISSIONS: 15th October, 2020.
Prizes: Cash prize along with the coveted title of becoming an ISF Fellow! 1st position: $400 2nd position: $250 3rd position: $150
Guidelines: Click here to download the detailed guidelines.
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