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Explanation of the generalizations of uncertainty principle from coordinate and momentum space periodicity
No full textGeneralizations of coordinate x-momentum px uncertainty principle, with Δx- and Δpx-dependent terms (Δ denoting standard deviation), (Formula presented.) have provided rich dividends as a poor person’s approach toward quantum gravity, because these can introduce coordinate and momentum scales (α,β ) that are appealing conceptually. However, these extensions of uncertainty principle are purely phenomenological in nature. Apart from the inherent ambiguity in their explicit structures, the introduction of generalized commutations relations compatible with the uncertainty relations has some drawbacks. In the present paper, we reveal that these generalized uncertainty principles can appear in a perfectly natural way, in canonical quantum mechanics, if one assumes a periodic nature in coordinate or momentum space, as the case may be. We bring in to light quite old (but not so well known) works by Judge and by Judge and Lewis that explain in detail how a consistent and generalized uncertainty principle is induced in the case of angle ϕ—angular momentum Lz, (Formula presented.) purely from a consistent implementation of periodic nature of the angle variable ϕ, without changing the ϕ,Lz canonical commutation relation. Structurally this is identical to the well-known extended uncertainty principle. We directly apply this formalism to formulate the ΔxΔpx extended uncertainty principle. We identify β with an observed length scale relevant in astrophysics context. We speculate about the α extension
FIRST CENOZOIC MACROFOSSIL RECORD OF POLYPODIACEAE FROM INDIA AND ITS BIOGEOGRAPHIC IMPLICATIONS
No full textPremise of research. Polypodiaceae, the largest leptosporangiate fern family, is distributed mainly in the tropical and subtropical regions of India, China, New Zealand, and Malaysia. This family has a rich macrofossil record in the Cenozoic sediments of China, but no macrofossil of Polypodiaceae has been reported from the Cenozoic sediments of India to date. Here, we report for the first time the occurrence of fossil frond remains resembling morphologically those of the extant microsoroid wart fern genus Microsorum Link from the late Miocene Siwalik sediments exposed around Sarkaghat, Mandi district of Himachal Pradesh, Western Himalaya, India. Methodology. The present frond fossils were revealed by careful removal of the overlying matrix and studiedunder light compound, stereo zoom, and inverted fluorescence microscopes. They are identified based on their detailed morphological (macro and micro) features and through the comparison with other modern Polypodiaceae genera as well as with earlier reported polypodiceous fern fossil species. Pivotal results. The fossil frond specimens are described here as a new species, namely, Palaeosorum siwalikum Kundu, Hazra et Khan sp. nov. The new Siwalik vascular cryptogam species is characterized by leaf shape (simple frond with entire margin), venation pattern (brochidodromous nature of secondary veins, tertiary and quaternary veins reticulate, anastomosing and forming a row of irregular or quadrangular-shaped areoles between two lateral secondary veins), and presence of free included veinlets (unbranched or forked, endingwith club-shaped hydathodes). Conclusions. These new fossil materials confirm the existence of a Microsorum-like plant in the Siwalik Miocene forests of Himachal Pradesh. We review in detail the fossil record and highlight the phytogeographic history of Polypodiaceae. In addition, we also suggest probable migratory routes for this fern family
Habitat Loss in the IUCN Extent: Climate Change-Induced Threat on the Red Goral (Naemorhedus baileyi) in the Temperate Mountains of South Asia
No full textClimate change has severely impacted many species, causing rapid declines or extinctions within their essential ecological niches. This deterioration is expected to worsen, particularly in remote high-altitude regions like the Himalayas, which are home to diverse flora and fauna, including many mountainous ungulates. Unfortunately, many of these species lack adaptive strategies to cope with novel climatic conditions. The Red Goral (Naemorhedus baileyi) is a cliff-dwelling species classified as “Vulnerable” by the IUCN due to its small population and restricted range extent. This species has the most restricted range of all goral species, residing in the temperate mountains of northeastern India, northern Myanmar, and China. Given its restricted range and small population, this species is highly threatened by climate change and habitat disruptions, making habitat mapping and modeling crucial for effective conservation. This study employs an ensemble approach (BRT, GLM, MARS, and MaxEnt) in species distribution modeling to assess the distribution, habitat suitability, and connectivity of this species, addressing critical gaps in its understanding. The findings reveal deeply concerning trends, as the model identified only 21,363 km2 (13.01%) of the total IUCN extent as suitable habitat under current conditions. This limited extent is alarming, as it leaves the species with very little refuge to thrive. Furthermore, this situation is compounded by the fact that only around 22.29% of this identified suitable habitat falls within protected areas (PAs), further constraining the species’ ability to survive in a protected landscape. The future projections paint even degraded scenarios, with a predicted decline of over 34% and excessive fragmentation in suitable habitat extent. In addition, the present study identifies precipitation seasonality and elevation as the primary contributing predictors to the distribution of this species. Furthermore, the study identifies nine designated transboundary PAs within the IUCN extent of the Red Goral and the connectivity among them to highlight the crucial role in supporting the species’ survival over time. Moreover, the Dibang Wildlife Sanctuary (DWLS) and Hkakaborazi National Park are revealed as the PAs with the largest extent of suitable habitat in the present scenario. Furthermore, the highest mean connectivity was found between DWLS and Mehao Wildlife Sanctuary (0.0583), while the lowest connectivity was observed between Kamlang Wildlife Sanctuary and Namdapha National Park (0.0172). The study also suggests strategic management planning that is a vital foundation for future research and conservation initiatives, aiming to ensure the long-term survival of the species in its natural habitat
Image Comparison Based On Local Pixel Clustering
No full textImage comparison is a fundamental step for monitoring images and has wide applications in many disciplines of sciences, including satellite imaging, medical research, quality control and so forth. This problem, however, is complicated because (i) the observed images often contain noise, (ii) the image intensity functions are discontinuous and have spatial structures. In the literature, a vast majority of the methods are intensity-based. However, such an approach is often questionable in real life situations where small changes in the background may not indicate an actual meaningful change in the images as long as the boundaries of the image objects remain the same. In this article, we propose a flexible and effective image comparison method based on local pixel clustering and construct a test statistic based on the Variation of Information metric. This is a feature based image comparison technique where edges or the jump points are considered as the primary features. Numerical examples and statistical properties show that the proposed image comparison method performs well in various real life scenarios
Identifying the genetic associations among the psoriasis patients in eastern India
No full textPsoriasis is a multifactorial genetic disorder manifested by hyperproliferation and abnormal differentiation of epidermal keratinocytes, along with the infiltration of inflammatory cells into the skin. Although ~80 genetic susceptibility variants were reported in psoriasis, many loci showed population-specific associations, warranting the need for more population-specific association studies in psoriasis. We determined the association of forty single nucleotide polymorphisms (SNPs) among 2136 psoriasis patients and normal individuals from eastern India. We investigated the expression of corresponding genes and evaluated the protein structure stability for the genes with susceptible coding variants. We found fifteen SNPs significantly associated with psoriasis, while additional three SNPs showed significant association when we classified the patients based on the presence of HLA-Cw6 allele. Epistatic interaction between HLA-Cw6 and other associated loci showed significant association with the SNPs at PSORS1 region, along with other five SNPs outside PSORS1. Three genes showed significant differential expression in psoriatic tissues compared to the adjacent normal skin tissues but were not differential when classified the patients based on their genotypes. SNP rs495337 at SPATA2 (Spermatogenesis Associated 2) showed a 1.2-fold increased risk among the HLA-Cw6 patients compared to combined samples. We found significant downregulation of SPATA2 among the patients with risk genotypes and HLA-Cw6 allele compared to the non-risk genotypes. Protein structure stability analysis showed reduced structural stability for all the mutant residues caused by the associated coding variants. Our study evaluated the genetic associations of psoriasis-susceptible variants in India and evaluated the possible functional significance of these associated variants in psoriasis
Improved Fault Analysis on Subterranean 2.0
No full textSubterranean 2.0, a NIST second round lightweight cryptographic primitive, was introduced by Daemen et al. in 2020. It has three modes of operation: Subterranean-SAE, Subterranean-deck, and Subterranean-XOF. So far, most of the existing practical-time implementable attacks on Subterranean-SAE fall under the nonce misuse setting scenario. In this paper, we present significantly improved Differential Fault Analysis on Subterranean-SAE and Subterranean-deck. We consider a more challenging framework of unknown fault injection round, and achieve improved execution time as well as data complexity over the best known fault attack available in the literature. We utilize deep neural networks and also correlation coefficient for generation of signatures and matching them. Two general frameworks are proposed for fault location identification assuming that fault injection round is unknown. Finally, we use a SATSAT solver to efficiently recover the embedded encryption key with no more than mathbf{5}5 distinct faults. Experimental results reveal that the total time (online phase) required to mount the attack on Subterranean-SAE (Subterranean-deck) is 1234.6 (1334.6) seconds
Irreducibility and Galois groups of truncated binomial polynomials
No full textFor positive integers n ≥ m, let Pn,m(x):=σj=0mn j xj = n 0 + n 1 x + ... + n mxm be the truncated binomial expansion of (1 + x)n consisting of all terms of degree ≤ m. It is conjectured that for n \u3e m + 1, the polynomial Pn,m(x) is irreducible. We confirm this conjecture when 2m ≤ n \u3c (m + 1)10. Also we show for any r ≥ 10 and 2m ≤ n \u3c (m + 1)r+1, the polynomial Pn,m(x) is irreducible when m ≥max{106, 2r3}. Under the explicit abc-conjecture, for a fixed m, we give an explicit n0,n1 depending only on m such that ∀ n ≥ n0, the polynomial Pn,m(x) is irreducible. Further ∀ n ≥ n1, the Galois group associated to Pn,m(x) is the symmetric group Sm
Jackknife empirical likelihood ratio test for testing mean time to failure order
No full textIn this paper, we propose a new non-parametric test for testing mean time to failure order. The asymptotic properties of the proposed test statistic are studied. We also develop a jackknife empirical likelihood (JEL) ratio test for testing the mean time to failure order. Using the Monte Carlo simulation study, we establish that the JEL ratio test has good power under various alternatives. Finally, we illustrate the proposed test procedure using two real data sets
Lane-Keeping Control of Automatic Steering Systems via Adaptive Fuzzy Sliding-Mode Approach
No full textThis article presents an adaptive control strategy for lane-keeping task of automatic steering systems via sliding-mode technique. First, considering the road-vehicle lateral dynamics, a standard single track steering model has been developed for the lane-keeping task. To cope with the time-variant nature of the longitudinal velocity and uncertainty of measurement, a class of interval type-2 fuzzy sets considered in this article are employed to reconstruct the steering system dynamics mathematical model. Based on the fuzzy system, an integral sliding surface is proposed and the asymptotic convergence criterion for the overall system is derived with extended dissipation. Furthermore, an adaptive control law is provided to achieve the reachability of the assigned sliding surface and improve the attenuation ability to unknown curvature and exogenous disturbance. Finally, several scenarios with different path-following tasks are given in the simulations. Results demonstrate that the proposed sliding-mode control method has the capability to track the road centerline and is robust to external unknown disturbances