Defence Research and Development Organisation
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Senescence, once considered as permanent cell cycle cessation, has now become a focal point for therapeutic interventions. Researchers are exploring ways to target senescent cells and improve health span. By eliminating these cells, we may delay age-related diseases and pave the way for healthier aging. One approach involves senomorphics, which are compounds designed to modulate the SASP (Senescence-Associated Secretory Phenotype). The SASP is a mix of signaling molecules that senescent cells release, affecting neighboring cells and the tissue microenvironment. By controlling the SASP, researchers aim to mitigate its pro-inflammatory effects and promote tissue regeneration. Clinical trials are underway to test various senolytic drugs—substances that remove senescent cells in a targeted manner. If successful, senolytics could revolutionize aging-related therapies, allowing us to age gracefully and maintain better health throughout life. This chapter introduces cellular senescence, its relevance in therapy, and the agents that target senescence, including senolytics, senomorphics, and SASP inhibitors. Finally, rejuvenation strategies to reverse cellular senescence are discussed and grouped into extrinsic and intrinsic methods on the basis of the level of intervention.
An equimolar mixture of 2-amino-6-methoxybenzothiazole and 2-hydroxy-4-methoxybenzaldehyde was used to produce a Schiff base ligand 5-methoxy-2-(((6-methoxybenzothiazol-2-yl)imino)methyl)phenol, HL, which was then examined by elemental analysis, IR, ¹H NMR, ¹³C NMR and ESI-mass spectrometry. The Co(II), Ni(II) and Cu(II) chlorides, acetates and ligands were combined in ethanol in a molar ratio of 1:1 to create the metal complexes [1-C16H19CoClN2O6S, 2- C18H22CoN2O8S, 3- C16H15NiClN2O4S, 4- C18H18NiN2O6S, 5- C16H15CuClN2O4S and 6- C18H18CuN2O6S]. To identify the structure of all metal complexes 1–6, elemental analysis, molar conductance, electronic spectra and IR spectra were used. The ligand HL functions as an uninegative bidentate via phenolic O- and azomethine N- atoms, according to spectral data. Theoretical studies were performed to investigate the interaction between the metal ions and the ligand HL. This included analysis of the HOMO–LUMO gap to assess electronic properties, Hirshfeld charge distribution to understand electron density changes upon complexation and calculation of the binding energy to evaluate the stability of the metal–ligand complexes. The Co(II) complexes have been given an octahedral geometry, Ni(II) complexes a tetrahedral geometry and Cu(II) complexes a square planar geometry. Studies of the binding of the metal complex to bovine serum albumin (BSA) have been undertaken with the aid of fluorescence and circular dichroism spectrometry.
Objective The present investigation was undertaken to determine the healing efficacy of Hippophae rhamnoides L. (sea buckthorn (SBT)) leaf aqueous lyophilised extract (SBTL-ALE) on a diabetic wound model in rats. The effect of SBTL-ALE was also evaluated on human epithelial cell lines (A431) by using in vitro wound closure and transwell migration assays. Method A total of four full-thickness excision-type wounds were created on the dorsal surface of streptozocin-induced diabetic rats. The animals were divided into two groups: control rats treated with soft white petroleum jelly and experimental rats treated with SBTL-ALE (5.0%, weight/weight) ointment applied topically, twice daily for seven days. Results SBTL-ALE significantly (p<0.05) accelerated the migration of epithelial cells in in vitro wound closure and transwell migration assays. Further, SBTL-ALE augmented the healing process by significantly (p<0.05) enhanced wound area contraction, faster complete epithelial closure, increased hydroxyproline (collagen) and hexosamine levels in diabetic rats. Histopathological findings confirmed the healing potential of SBTL-ALE. Immunohistochemical analyses showed increased expression of transforming growth factor (TGF)-β and α-smooth muscle actin in SBTL-ALE-treated wounds of diabetic rats. Superoxide dismutase, catalase and reduced glutathione levels increased, whereas reactive oxygen levels were decreased significantly (p<0.05) in SBTL-ALE-treated wounds compared to diabetic controls, which conferred redox homeostasis. Conclusion Our results suggest that SBTL-ALE accelerated transdermal wound healing in diabetic rats by increasing the rate of wound contraction, enhancing levels of collagen, hexosamine and endogenous antioxidants, and reducing oxidative stress.
The current research work is an initiative taken for the remediation of water contaminated with carbon nanomaterials (CNMs) by employing microemulsion (ME) and cloud point extraction (CPE) methodologies. CNMs viz., graphene oxide (GO) and multiwalled carbon nanotube (MWCNT) dispersed in water (2000 mg/L) were extracted in the oil phase and surfactant phase based on optimized ME and CPE parameters which include oil, pH, incubation temperature, the content of non-ionic-surfactants (Triton X-100) and NaCl. The supernatant and extracted CNMs from the ME and CPE experiments were analyzed using UV–Vis spectroscopy, DLS, SEM, TEM, XRD, and Raman spectroscopy. The disappearance of characteristic peaks of GO and MWCNT in the UV–Vis, Raman, and DLS spectra of the treated water samples signifies the absence of nanoparticles in the remediated water. A highly efficient removal (~ 97%) of GO and MWCNT from contaminated water through CPE in one cycle was achieved compared to ME (~ 90%) in two recovery cycles. Thus, the CPE technique efficiently removes CNMs from polluted water for their benign disposal, mitigating potential ecological and health risks. Graphical Abstract
Organic phase change materials (PCMs) have gained huge importance for thermal energy storage systems, but their applicability is restricted due to their low thermal conductivity and hardness. The aim of this research work is to solve the problem by developing a novel organic binary eutectic PCM employing paraffin wax and coconut oil in the eutectic mixture (ratio 1:1) to soften the PCM for thermal comfort applications. 3D expanded graphite (EG) was used as a filler to enhance the thermophysical properties of eutectic-EG PCM composite formed by melt-mixing technique. The percolation limit of EG was 0.5 wt-% to form the thermal network in PCM matrix. The thermal conductivity of eutectic-EG PCM composite enhanced significantly from 0.2 W m ⁻¹ K ⁻¹ to 0.55 W m ⁻¹ K ⁻¹ at 2 wt-% of EG in pristine PCM. Differential scanning calorimetry (DSC) was carried out to analyse the energy storage enthalpies and temperatures of composites. The 50 consecutive thermal heating and cooling cycles performed by conventional heating system showed the good thermal reliability of the composite. The numerical 2D simulation was conducted to reveal the heat propagation behaviour in the developed composite with the post-EG addition and to validate the enhanced thermal conductivity results obtained experimentally. The cost analysis results reveals that the cost per mean power of the composite is composite is approximately 100% lower than the pristine PCM. The developed composite's outstanding energy storage property indicates its potential for developing the soft heating pads/cartridges for human comfort and also the solar thermal energy storage applications for medium temperature ranges.
A three‐party post‐quantum key agreement protocol involves server with two communicating parties securely agreeing on a shared secret key in a way that is resistant to quantum attacks. Once the shared secret key is shared using authenticated key agreement protocol, then user (A), and user (B) can use it for securing communication channel using symmetric‐key encryption AES‐256 algorithm. Although there are few third‐party post‐quantum authenticated and key agreement schemes exist, but the recent studies in this paper illustrates that they are not satisfying properties like unlinkability, anonymity, perfect forward secrecy, and signal leakage attacks. Therefore, the proposed protocol ensures anonymity, unlinkablity, perfect forward secrecy, and resistant against signal leakage attacks. The proposed protocol uses different random numbers for each of sessions and ensures freshness of the session key to maintain forward secrecy. In this protocol, the user (A) only communicates with server, and establish an authenticated session key with user (B) which avoids server overheads. The use of ring learning with errors (RLWE) instead of the simpler learning with errors (LWE) is primarily motivated by the need for efficiency, compactness, and scalability in cryptographic applications. A comparative study, including both performance and security assessments, demonstrates that the proposed design is more secure and efficient.
The Himalayan cryosphere is dynamic, and changing climate conditions threaten breach of glacial lakes. A number of glacial lake outburst floods (GLOFs) occurred in the Himalayas in the recent past, affecting people and infrastructures. Assessment of high-altitude glacial lakes is required to avoid associated hazards and mitigate the impacts. In this study, we have made an inventory of naturally formed lakes within the Sikkim Himalayas, including Nepal, Bhutan, and China, and discussed the GLOF susceptibility. A total of 399 lakes have been identified, out of which 281 lakes have an areal coverage greater than 0.01 Km2. Monitoring temporal changes shows a higher rate of areal increment for the lakes close to the western boundary of Sikkim. Using an Analytical Hierarchy Process (AHP) based on fifteen parameters, a number of glacial lakes show medium to high GLOF susceptibility in the Himalayan and surrounding regions. Three backpropagation multilayer perceptron neural network (BPMLPNN) models with Bayesian Regularization (BR-), Levenberg-Marquardt (LM-), and Gradient Descent with Momentum and Adaptive Learning Rate (GDX-) optimizers are designed to have better prediction accuracies compared to the AHP target scores. The BR-BPMLPNN model is observed with maximum performance and close similitude with the results obtained from the LM-BPMLPNN model.
With rapid advancements in detector technology in the last couple of decades in the field of infrared (IR), infrared seeker missiles have become a formidable threat to warships in hostile environments. In modern naval operations, effective infrared signature management stands out as a critical element influencing the security strategies of warships. IR radiation is capable of passing through the atmosphere in Mid-Wave Infrared (MWIR) (3–5 µm) and Long-Wave Infrared (LWIR)(8–12 µm) ranges only and given that all contemporary infrared seeker missiles operate in MWIR and LWIR ranges, the paper presents a methodology to estimate a warship’s infrared radiation in these spectral ranges. This paper proposes a holistic approach for complete IR signature management of a warship, encompassing three essential components viz., IR prediction, IR signature suppression, and IR signature measurement.
Unmanned Aerial Vehicles (UAV) have become a part of regular inventory for military and civilian applications. At present, UAVs are designed with design methodology of manned aircrafts with little fine tuning in configuration to integrate the payloads, datalink, etc. There is a need to identify important metrics for UAV to facilitate the UAV developers to realize an optimum configuration. Towards this, a system of categorizing and defining the metrics is proposed for Intelligence, Surveillance and Reconnaissance (ISR) UAVs. The metrics are categorized as performance metrics, design metrics and cross-cutting metrics based on the stakeholder categorization of Customer, Developer and Facilitator. The performance metrics for ISR UAV related to area coverage, range, time of flight and ceiling are compiled. A preliminary estimation of performance metrics for various types of ISR UAVs with Electro Optic payload is carried out to obtain insight about their ISR capability.
The Binary Decision Diagrams(BDD) have played important role in hardware verification, model checking, and logic synthesis, where they optimize the handling of complex Boolean expressions by reducing redundancy and ensuring canonical representation. Harish Sahu et. al. in 2017 gave a practical way to use ROBDDs to attack stream ciphers and compared different ways of operating AND operations between BDDs. We show that this method is not the universally fastest to perform a binary operation between any two objects. A successful attack requires the reduction of time and space complexity to the greatest extent possible. In this direction, we propose a new method that uses BDDs to attack any stream cipher with time complexity of O(n4Mˉ2)O(\frac{n}{4}\bar{M}^2), and demonstrate its application to a well known estream cipher, Trivium. We present Time and Space Analysis by means of several experiments and find that our method outperforms the earlier one in time and under certain conditions in space. Through comprehensive time and space analysis conducted via multiple experiments, we demonstrate that our method outperforms the previous approach in terms of time efficiency and, under specific conditions, in space efficiency as well.
Optimal food production is achieved when crops receive the necessary nutrients, and the desired levels of temperature, humidity, solar radiation, and sufficient water. Climate Control Agriculture, or Controlled Environment Agriculture, utilizes a technology-based approach to grow plants in a controlled environment. This study focuses on the experimental investigation of polycarbonate sheets doped with TiO2, ZnO, and zeolite nanoparticles for potential use in polyhouse applications. The thermal performance of these synthesized and standard polycarbonate sheets was tested in a laboratory setting. A specialized experimental setup, consisting of two cabinets, was designed and fabricated for this purpose. Ten synthesized sheets each with thicknesses of 50 μm and 70 μm, and two commercial sheets of 70 μm thickness were tested experimentally in the laboratory for their thermal performance. Results indicated that % doping concentration of 0.3% was the most effective, while 0.1% was the least effective. Among the three doping materials, TiO2-doped sheets demonstrated superior ultra-violate light absorption capacity due to their high refractive index and band gap energy, which enhances their ability to absorb and scatter ultra-violate light. ZnO offered stronger UV protection than the remaining three materials. However, it has a lower refractive index than TiO2. Its overall thermal performance was lower than TiO2. The desired properties of nanocomposites for use in polyhouse applications such as thermal performance in the laboratory, UV protection, mechanical strength and durability, transparency, photostability, and safety were compared based on the experimental results and the data available in the literature. It was concluded that polycarbonate doped with ZnO and TiO2 nanoparticles was the most suitable.
Polymeric membranes have emerged as a versatile and efficient liquid separation technology, addressing the growing demand for sustainable, high-performance separation processes in various industrial sectors. This review offers an in-depth analysis of recent developments in polymeric membrane technology, focusing on materials’ advancements, innovative fabrication methods, and strategies for improving performance. We discuss the underlying principles of membrane separation, selecting suitable polymers, and integrating novel materials, such as mixed-matrix and composite membranes, to enhance selectivity, permeability, and antifouling properties. The article also highlights the challenges and limitations associated with polymeric membranes, including stability, fouling, and scalability, and explores potential solutions to overcome these obstacles. This review aims to guide the development of next-generation polymeric membranes for efficient and sustainable liquid separation by offering a detailed analysis of current research and future directions.
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1,671 members
Ruchi Baghel
  • Institute of Nuclear Medicine and Allied Sciences (INMAS)
Deepti Majumdar
  • Defence Institute of Physiology and Allied Sciences
Kaushik Halder
  • Defence Institute of Physiology and Allied Sciences
Bipul Rabha
  • Defence Research Laboratory (DRL)
Ashutosh Kedar
  • Electronics & Radar Devlopment Establishment (LRDE)
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