Estimating phase transition of perturbed J1-J2 Heisenberg quantum chain in mixtures of ground and first excited states

We show that the nearest neighbour entanglement in a mixture of ground and first excited states - the subjacent state - of the J1-J2 Heisenberg quantum spin chain can be used as an order parameter to detect the phase transition of the chain from a gapless spin fluid to a gapped dimer phase. We study the effectiveness of the order parameter for varying relative mixing probabilities between the ground and first excited states in the subjacent state for different system sizes, and extrapolate the results to the thermodynamic limit. We observe that the nearest neighbour concurrence can play a role of a good order parameter even if the system is in the ground state, but with a small probability of leaking into the first excited state. Moreover, we apply the order parameter of the subjacent state to investigate the response to introduction of anisotropy and of glassy disorder on the phase diagram of the model, and analyse the corresponding finite-size scale exponents and the emergent tricritical point.Comment: 14 pages, 9 figure

MSQNet: Actor-agnostic Action Recognition with Multi-modal Query

Existing action recognition methods are typically actor-specific due to the intrinsic topological and apparent differences among the actors. This requires actor-specific pose estimation (e.g., humans vs. animals), leading to cumbersome model design complexity and high maintenance costs. Moreover, they often focus on learning the visual modality alone and single-label classification whilst neglecting other available information sources (e.g., class name text) and the concurrent occurrence of multiple actions. To overcome these limitations, we propose a new approach called 'actor-agnostic multi-modal multi-label action recognition,' which offers a unified solution for various types of actors, including humans and animals. We further formulate a novel Multi-modal Semantic Query Network (MSQNet) model in a transformer-based object detection framework (e.g., DETR), characterized by leveraging visual and textual modalities to represent the action classes better. The elimination of actor-specific model designs is a key advantage, as it removes the need for actor pose estimation altogether. Extensive experiments on five publicly available benchmarks show that our MSQNet consistently outperforms the prior arts of actor-specific alternatives on human and animal single- and multi-label action recognition tasks by up to 50%. Code will be released at https://github.com/mondalanindya/MSQNet

Time-varying Signals Recovery via Graph Neural Networks

The recovery of time-varying graph signals is a fundamental problem with numerous applications in sensor networks and forecasting in time series. Effectively capturing the spatio-temporal information in these signals is essential for the downstream tasks. Previous studies have used the smoothness of the temporal differences of such graph signals as an initial assumption. Nevertheless, this smoothness assumption could result in a degradation of performance in the corresponding application when the prior does not hold. In this work, we relax the requirement of this hypothesis by including a learning module. We propose a Time Graph Neural Network (TimeGNN) for the recovery of time-varying graph signals. Our algorithm uses an encoder-decoder architecture with a specialized loss composed of a mean squared error function and a Sobolev smoothness operator.TimeGNN shows competitive performance against previous methods in real datasets.Comment: Published in IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) 2023, Greec

Magnetodielectric effect of Graphene-PVA Nanocomposites

Graphene-Polyvinyl alcohol (PVA) nanocomposite films with thickness $120 \mu m$ were synthesized by solidification of PVA in a solution with dispersed graphene nanosheets. Electrical conductivity data were explained as arising due to hopping of carriers between localized states formed at the graphene-PVA interface. Dielectric permittivity data as a function of frequency indicated the occurrence of Debye-type relaxation mechanism. The nanocomposites showed a magnetodielectric effect with the dielectric constant changing by 1.8% as the magnetic field was increased to 1 Tesla. The effect was explained as arising due to Maxwell-Wagner polarization as applied to an inhomogeneous two-dimensional,two-component composite model. This type of nanocomposite may be suitable for applications involving nanogenerators.Comment: 13 pages, 11 figure

Recovery of Missing Sensor Data by Reconstructing Time-varying Graph Signals

Wireless sensor networks are among the most promising technologies of the current era because of their small size, lower cost, and ease of deployment. With the increasing number of wireless sensors, the probability of generating missing data also rises. This incomplete data could lead to disastrous consequences if used for decision-making. There is rich literature dealing with this problem. However, most approaches show performance degradation when a sizable amount of data is lost. Inspired by the emerging field of graph signal processing, this paper performs a new study of a Sobolev reconstruction algorithm in wireless sensor networks. Experimental comparisons on several publicly available datasets demonstrate that the algorithm surpasses multiple state-of-the-art techniques by a maximum margin of 54%. We further show that this algorithm consistently retrieves the missing data even during massive data loss situations.Comment: Five pages, two figures, Accepted at EUSIPCO 202

Ovarian filariasis presenting as tubo-ovarian mass: Report of a rare case

Filariasis of ovary is rare. Exact incidence is not known. Herein, we report a case of filarial worm affecting right ovary in a 35-year-old female patient who presented with chronic pelvic pain. Ultrasonography of lower abdomen revealed a tubo-ovarian mass on the right side. Right-sided salpingo-oophorectomy was done. Grossly, ovary was slightly enlarged in size (5 cm × 2.5 cm × 2 cm). Cut surface showed several tiny cysts at the periphery. The lumen of the fallopian tube was blocked. Histopathological examination of the ovary showed lymphangiectasia with microfilaria in one of the dilated lymphatics. Few cystic follicles were also seen in the sections. Section from the tube showed features of chronic salpingitis. She was given a course of diethylcarbamazine citrate (DEC) for 3 weeks postoperatively. On follow-up, the patient was doing well without any complication

Status of glucose metabolism including insulin resistance and beta cell function in overtly iron loaded Thalassemia patients

BACKGROUND Abnormality of glucose metabolism is a frequent complication in Thalassemia patients. Both insulin deficiency and insulin resistance has been proposed in its pathogenesis. Some form of abnormality in glucose metabolism is expected at an earlier age in these patients in developing countries like India and Nepal where iron overload is excessive due to lack of chelation therapy. MATERIALS AND METHODS Fasting serum glucose and fasting serum insulin (FSI) were measured in 40 beta-thalassemia major patients, 40 Ebeta- thalassemia patients and 40 controls, all aged between 5 and 12 years. 2 hours after an appropriate dose of oral glucose feed (Children ingested 1.75 g/kg body weight maximum 75 gram dissolved in 250 to 300 ml water) blood samples were drawn again to measure post prandial serum glucose. Iron overload was assessed by measuring liver size, spleen size, total amount of packed cells transfused and serum ferritin. Insulin resistance (IR), insulin sensitivity (%S) and beta cell functions (%B) were derived from the measured laboratory parameters using the latest version of Homeostatic Model Assessment (HOMA) calculator software. RESULTS No one had impaired glucose metabolism or diabetes mellitus beta-thalassemia major patients showed evidence of insulin resistance in the form of significantly higher fasting serum insulin (p value 0.002), IR (p value 0.003), %B (p value 0.017) and significantly lower %S (0.002) when compared with controls. FSI showed positive correlation with total amount of packed cells received (r=0.372, p=0.018), serum ferritin (r=0.345, p=0.029) and spleen size (r=0.427, p=0.006). Similarly, IR also showed positive correlation with total amount of packed cells received (r=0.388, p=0.013), serum ferritin (r=0.336, p=0.034) and spleen size (r=0.425, p=0.005). %S showed negative correlation with all these parameters. %B didn&rsquo;t show any statistically significant correlation with these parameters.Ebeta- thalassemia patients didn&rsquo;t have any statistically significant difference in FSI, IR, %S and %B than controls. CONCLUSION Insulin resistance develops as the earliest abnormality in glucose metabolism in overtly iron loaded beta thalassemia major patients at an early age. Ebeta- thalassemia patients with milder phenotype do not develop dysfunction of glucose metabolism at such an early age.DOI: http://dx.doi.org/10.3126/jcmsn.v10i3.12774 Journal of College of Medical Sciences-Nepal, 2014, Vol-10, No-3, 29-36</p

Immunocytochemistry: It′s role in diagnosis of undifferentiated neoplasms by fine needle aspiration cytology

Background: Fine needle aspiration cytology (FNAC) is a rapid, cheap and reliable method for diagnosing any accessible lesion. However, there remains a group of malignant undifferentiated neoplasms, which can only be categorized with the help of immunocytochemistry (ICC). The categorization is important due to their vast difference in treatment and prognosis. Aim: To evaluate the effectiveness of ICC in categorizing the undifferentiated neoplasms diagnosed on routine FNAC smears. Materials and Methods: Thirty six cases of undifferentiated neoplasms were selected from a group of total 78 cytology cases of undifferentiated tumors from different sites like head and neck, lymph node, soft tissue etc. These were then subjected to a panel of ICC markers based on the clinical and cytomorphological features. Results: Of these, 21 were simple, ten were computerized tomography guided and five were ultrasound guided FNACs respectively. All the 78 cases were confirmed by histopathological examination and immunohistochemistry. Of the 36 cytological cases, final diagnosis correlated in 30 cases histologically. The six cases were incorrect either due to inadequate material on the smears (three cases) or false positive staining (three cases). Conclusions: Our study found that ICC is a sensitive and specific method for early and definitive diagnosis of undifferentiated neoplasms. However, selection of antibodies must be judicious to make it cost effective

Interplay of Hydrophobic and Electrostatic Interactions in Modulation of Protonation–Deprotonation Equilibria of Two Positional Isomers in Their Complexes with Cucurbiturils

Elucidation of host–guest chemistry of 2-(4′-pyridyl)­benzimidazole (4PBI) and 2-(2′-pyridyl)­benzimidazole (2PBI) with cucurbiturils in aqueous solution is rather challenging. The guest molecules are capable of binding in three different states of protonation: cation C, tautomer T, and normal N. Charge distribution on the species governs the formation of the inclusion complexes. Binding modes of the guest molecules with cucurbiturils have been investigated by proton NMR spectroscopy. 4PBI binds with its benzimidazole ring pointing inward, while the binding mode is opposite for 2PBI. This difference is governed by the position of substitution of the pyridyl ring. Energetics of complexation has been studied by quantum chemical calculations for 4PBI-CB as 2PBI-CB type complexes, for each form (C, T, and N) of both the molecules. Release of high energy water from cucurbituril cavity is the main driving force for complexation. Excited state proton transfer (ESPT) in 2PBI and 4PBI are affected strongly upon complexation, as is manifested in steady state and time-resolved fluorescence experiments