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Envy-Free and Efficient Allocations for Graphical Valuations
No full textWe consider the complexity of finding envy-free allocations for the class of graphical valuations. Graphical valuations were introduced by Christodoulou et al. [14] as a structured class of valuations that admit allocations that are envy-free up to any item(EFX). These are valuations where every item is valued by two agents, lending a (simple) graph structure to the utilities, where the agents are vertices and are adjacent if and only if they value a (unique) common item. Finding envy-free allocations for general valuations is known to be computationally intractable even for very special cases: in particular, even for binary valuations, and even for identical valuations with two agents. We show that, for binary graphical valuations, the existence of envy-free allocations can be determined in polynomial time. In contrast, we also show that allowing for even slightly more general utilities {0,1,d} leads to intractability even for graphical valuations. This motivates other approaches to tractability, and to that end, we exhibit the fixed-parameter tractability of the problem parameterized by the vertex cover number of the graph when the number of distinct utilities is bounded. We also show that, all graphical instances that admit EF allocations also admit one that is non-wasteful. Since EFX allocations are possibly wasteful, we also address the question of determining the price of fairness of EFX allocations. We show that the price of EFX with respect to utilitarian welfare is one for binary utilities, but can be arbitrarily large {0,1,d} valuations. We also show the hardness of deciding the existence of an EFX allocation which is also welfare-maximizing and of finding a welfare-maximizing allocation within the set of EFX allocations
Alpha-tocopherol conjugated DNA tetrahedron with enhanced cellular uptake and selective cytotoxicity for cancer therapeutics
No full textOne of the most fatal diseases in the world, cancer, lacks proper therapies that are toxic to cancer cells and specifically kill them. A newly emerging field, DNA nanotechnology facilitates the design of programmable, biocompatible DNA-based nanostructures, with applications spanning drug delivery, biosensing, and a number of applications in biomedical and therapeutics. However, the negatively charged outer leaflet of the plasma membrane poses challenges for the uptake of negatively charged DNA nanostructures. Strategies such as functionalizing DNA nanostructures with cationic lipids have been attempted, but these approaches have yielded conflicting results and certain limitations including stability and ambiguity of lipid functionalisation. Additionally, drug delivery using DNA tetrahedron (TD) and other conventional therapies has shown off-target effects due to the non-specificity of the drug. To address these challenges, this study utilizes a hydrophobic molecule, alpha-tocopherol succinate (AT), known for its selective cytotoxicity towards malignant cells over normal cells at appropriate concentrations. Covalently conjugating AT with TD preserved its selective toxicity property and enhance the cellular internalisation of DNA tetrahedron in specific cell lines. ROS generation was increased and led to apoptosis in malignant cell lines specifically. This suggests the development of a novel system with specific cytotoxicity towards cancer cells with increased uptake
On the Inversion of Generalized V-Line Transform of a Vector Field in ℝ2
No full textThis article studies the inverse problem of recovering a vector field supported in (Formula presented.), the disk of radius (Formula presented.) centered at the origin, through a set of generalized broken ray/V-line transforms, namely, longitudinal and transverse V-line transforms. Geometrically, we work with broken lines that start from the boundary of a disk and break at a fixed angle after traveling a distance along the diameter. We derive two inversion formulas to recover a vector field in (Formula presented.) from the knowledge of its longitudinal and transverse V-line transforms over two different subsets of aforementioned broken lines in (Formula presented.)
Ultrasound Shear Wave Attenuation Estimates are Sensitive to In situ Fluid Content: In vitro and Ex vivo Studies
No full textIn shear wave elastography, viscoelastic properties of tissues can be estimated by fitting a rheological model to the phase velocity dispersion curve. However, there is a lack of consensus on the model that best represents tissue behavior. Model-free elastography approaches based on shear wave attenuation (SWA) and dispersion slope analysis have been reported previously. This study evaluated the ability of SWA and dispersion slope analysis to assess fluid content in situ using viscoelastic phantoms and ex vivo chicken breast. Model-free parameters were estimated in viscoelastic phantoms (with fluid percentages ranging from 72.6% to 79.9%, and pre- and post-compression by 10%) and ex vivo chicken breast samples pre- and post-hydration. Estimates of SWA were computed using the frequency-shift (FS) and the attenuation measuring shear wave elastography (AMUSE) methods. Dispersion slopes were computed from the phase velocity dispersion curves. The SWA coefficient estimates were strongly correlated with the fluid percentages in phantoms (r = 0.86 and 0.92 for FS and AMUSE methods, respectively, p < 0.001). However, no trends were observed for dispersion slope estimates (r = −0.73, p < 0.001). Thus, SWA was found to be a more sensitive parameter than the dispersion slope for differentiating phantoms with a range of in situ fluid content. Additionally, when phantoms were subjected to compression, SWA was sensitive to changes in compression-induced fluid variations in situ (p < 0.05), but dispersion slope showed no such trends (p = 0.12). The SWA estimates of ex vivo samples significantly increased post-hydration using both methods (p < 0.05), while the dispersion slope decreased. The findings of this study demonstrate that SWA is sensitive to fluid content in situ, which motivates its further development as a marker to assess pathological conditions
Network on Chips - The Journey Overview
No full textThis tutorial aims at highlighting the NoC journey from its origins till date. We also aim at giving an insight into the different path choices faced at different times and the preferred paths taken. With the necessary insight into the past and the present of the NoCs, we will dwell on the challenges and solutions being considered around the world. We shall also talk about the direction in which we are heading and the expected road ahead
Search for Continuous Gravitational Waves from Known Pulsars in the First Part of the Fourth LIGO-Virgo-KAGRA Observing Run
No full textContinuous gravitational waves (CWs) emission from neutron stars carries information about their internal structure and equation of state, and it can provide tests of general relativity. We present a search for CWs from a set of 45 known pulsars in the first part of the fourth LIGO-Virgo-KAGRA observing run, known as O4a. We conducted a targeted search for each pulsar using three independent analysis methods considering single-harmonic and dual-harmonic emission models. We find no evidence of a CW signal in O4a data for both models and set upper limits on the signal amplitude and on the ellipticity, which quantifies the asymmetry in the neutron star mass distribution. For the single-harmonic emission model, 29 targets have the upper limit on the amplitude below the theoretical spin-down limit. The lowest upper limit on the amplitude is 6.4 × 10-27 for the young energetic pulsar J0537-6910, while the lowest constraint on the ellipticity is 8.8 × 10-9 for the bright nearby millisecond pulsar J0437-4715. Additionally, for a subset of 16 targets, we performed a narrowband search that is more robust regarding the emission model, with no evidence of a signal. We also found no evidence of nonstandard polarizations as predicted by the Brans-Dicke theory
Experimental investigations on the productivity increase of solar stills utilising hybrid nanomaterials and water-cooling techniques
No full textSolar stills are simple devices that can be used to remove salts from water. However, it has a lower distillate yield; hence, it is not popular. Increasing the solar energy collection at the absorber may help to address these issues. This is feasible by adopting highly absorbent energy storage substances. Hybrid nanomaterials have significant potential for this purpose, and they can boost the absorptivity of the absorber plate of solar stills. Taking this into account, a hybrid nanomaterial was synthesized in a laboratory and applied to the surface of a solar still absorber to achieve higher performance. Iron oxide (Fe2O3) and copper oxide (Cu2O) nanoparticles were used in a 50:50 ratio. In addition, the current research employed a water sprinkler to enhance the condensation rate in the condensing region and consequently increase the distillation output of the solar still. A cooling water flow rate of 10 kg/h was used to sprinkle the condensing surface. According to the results, combining Fe2O3 and Cu2O with epoxy resin increased the efficiency of the solar still by 34% when using a glass cooling approach and by 28% when operating without a glass cover cooling technique
Design and synthesis of ?-conjugated donor-acceptor styryl dyes for subcellular and tissue imaging
No full textVeriBench: Benchmarking Large Language Models for Verilog Code Generation and Design Synthesis
No full textIn the rapidly advancing field of hardware design, Electronic Design Automation (EDA) tools can be significantly improved using Machine Learning. This study evaluates the efficacy of various Large Language Models (LLMs) for automating Electronic Design Automation for Verilog design, testbench generation, and Formal Verification (FV) assertion synthesis by comparing 3 closed-source LLMs and 14 Open-Source LLM variants. In our setup of 33 Verilog designs, ChatGPT-4 generates 22 synthesizable Verilog designs in one-shot without feedback, while the Llama 3 (8B) model generates 20. Both models generate all testbenches correctly, 9 of which are given in our setup. For generating Formal Verification properties, ChatGPT-4 generates all properties correctly, whereas Llama 3 synthesizes 7 out of 9 properties correctly. Of the sample synthesized in Vivado, ChatGPT-4 codes result into power-efficient designs as compared to Llama-3, whereas in Genus there is no clear winner. These results underscore the efficacy of open-source models, which perform competitively despite having significantly fewer parameters (8 billion) compared to closed-source models such as ChatGPT-4. This study demonstrates the potential of parameter-efficient, open-source models for hardware design and verification tasks
SLICE-TUNE: A System for High Performance DNN Autotuning
No full textAutotuning DNN models prior to their deployment is an essential but time-consuming task. Using expensive (and power-hungry) GPU and TPU accelerators efficiently is also key. Since DNNs do not always use a GPU fully, spatial multiplexing of multiple models can provide just the right amount of GPU resources for each DNN. We find that a DNN model tuned with the maximum GPU resources has higher inference latency if less GPU resources are available at inference time. We present methods to tune a DNN model, so that we provide the right amount of accelerator resources during tuning. Thus, even when a wide range of GPU resources are available at inference time, the tuned model achieves low inference latency. Further, existing autotuning frameworks take a long time to tune a model due to inefficient utilization of the client and server-side CPU and GPU. Our system, SLICE-TUNE., improves several autotuning frameworks to effciently use system resources by re-thinking the partitioning of tasks between the client and server (where models are profiled on the server GPU), in a Kubernetes environment. We increase parallelism during tuning by sharding the tuning model across multiple tuning application instances, providing concurrent tuning of different operators of a model. We also scale server instances to achieve better GPU multiplexing. SLICE-TUNE. reduces DNN autotuning time in a single GPU and in GPU clusters. SLICE-TUNE. decreases DNN autotuning time by up to 75%, and increase autotuning throughput by a factor of 5, across 3 different autotuning frameworks (TVM, Ansor, and Chameleon)