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Weak topological insulators are elusive topological materials that were subjected to relatively few experimental studies in the past owing to the lack of stable systems. Here, a detailed investigation of the low-temperature electrical transport on Bi1Se1 thin films, a weak topological insulator, over a wide range of thicknesses has been carried out. Robust signatures of weak anti-localization were observed from the electrical transport measurements where the magnetic field is applied perpendicular and parallel to the sample plane. The low-field data are analyzed using the Hikami–Larkin–Nagaoka equation. By combining the transport parameters (α, L∅) extracted from both perpendicular and parallel field measurements, our results indicate that apart from three-dimensional bulk states, 2D surface states are also present in our system and their origin could be linked to the weak topological nature of Bi1Se1. [ABSTRACT FROM AUTHOR]

Weak topological insulators are elusive topological materials that were subjected to relatively few experimental studies in the past owing to the lack of stable systems. Here, a detailed investigation of the low-temperature electrical transport on Bi1Se1 thin films, a weak topological insulator, over a wide range of thicknesses has been carried out. Robust signatures of weak anti-localization were observed from the electrical transport measurements where the magnetic field is applied perpendicular and parallel to the sample plane. The low-field data are analyzed using the Hikami–Larkin–Nagaoka equation. By combining the transport parameters (α, L∅) extracted from both perpendicular and parallel field measurements, our results indicate that apart from three-dimensional bulk states, 2D surface states are also present in our system and their origin could be linked to the weak topological nature of Bi1Se1. [ABSTRACT FROM AUTHOR]

The ability to respond flexibly to an ever-changing environment relies on the orbitofrontal cortex (OFC). However, how the OFC associates sensory information with predicted outcomes to enable flexible sensory learning in humans remains elusive. Here, we combine a probabilistic tactile reversal learning task with functional magnetic resonance imaging (fMRI) to investigate how lateral OFC (lOFC) interacts with the primary somatosensory cortex (S1) to guide flexible tactile learning in humans. fMRI results reveal that lOFC and S1 exhibit distinct task-dependent engagement: while the lOFC responds transiently to unexpected outcomes immediately following reversals, S1 is persistently engaged during re-learning. Unlike the contralateral stimulus-selective S1, activity in ipsilateral S1 mirrors the outcomes of behavior during re-learning, closely related to top-down signals from lOFC. These findings suggest that lOFC contributes to teaching signals to dynamically update representations in sensory areas, which implement computations critical for adaptive behavior. How the prefrontal cortex interacts with sensory cortex for behavioral adaptation in humans is unclear. Here, Wang et al. show that prediction-error related activity in lateral orbitofrontal cortex is conveyed as a teaching signal to update the outcome representation in sensory cortex. [ABSTRACT FROM AUTHOR]

Increasing population size and economic dependence on the coastal zone, coupled with the growing need for residential, agricultural, industrial, commercial and green space infrastructure, are key drivers of land reclamation. Until now, there has been no comprehensive assessment of the global distribution of land use on reclaimed space at the coast. Here, we analyze Landsat satellite imagery from 2000 to 2020 to quantify the spatial extent, scale, and land use of urban coastal reclamation for 135 cities with populations in excess of 1 million. Findings indicate that 78% (106/135) of these major coastal cities have resorted to reclamation as a source of new ground, contributing a total 253,000 ha of additional land to the Earth's surface in the 21st century, equivalent to an area the size of Luxembourg. Reclamation is especially prominent in East Asia, the Middle East, and Southeast Asia, followed by Western Europe and West Africa. The most common land uses on reclaimed spaces are port extension (>70 cities), followed by residential/commercial (30 cities) and industrial (19 cities). While increased global trade and the rapid urbanization have driven these uses, we argue that a city's prestigious place‐making effort to gain global reputation is emerging as another major driver underlying recent reclamation projects to create tourist and green spaces Meanwhile, the study suggests that 70% of recent reclamation has occurred in areas identified as potentially exposed to extreme sea level rise (SLR) by 2100 and this presents a significant challenge to sustainable development at the coast. Plain Language Summary: Coastal regions face enormous pressure from growing human footprints, especially given the current rates of sea‐level rise. It is now recognized that seawards extension of the land through land reclamation and infrastructure development, at least partly in response to increased vulnerability induced by extreme storm surge events, is also a feature of recent coastal dynamics, especially in the world's coastal megacities Despite its growing global importance and reach worldwide, coastal reclamation is regarded as a local issue. Subsequently, the scale, intensity, and justification are not globally known, rather they are documented through localized case studies. By leveraging advanced satellite and cloud computing technology, this study aims to map the global state of 21st coastal land reclamation and to highlight the risk of such an anthropogenic footprint at the coast in the era of SLR. Key Points: 253,000 ha of additional land to the Earth's coastal surface in the 21st century, equivalent to an area the size of LuxembourgCoastal Reclamation is especially prominent in East Asia, the Middle East, and Southeast Asia, followed by Western Europe and West AfricaWe suggest that 70% of recent reclamation has occurred in areas identified as high risk to extreme SLR by 2100 [ABSTRACT FROM AUTHOR]

This study explores the spatio-temporal distribution and trends on monthly, seasonal, and annual scales of rainfall in the central Punjab districts of Punjab province in Pakistan by using observation and satellite data products. The daily observed data was acquired from the Pakistan Metrological Department (PMD) between 1983 and 2020, along with one reanalysis, namely the Climate Hazard Infrared Group Precipitation Station (CHIRPS) and one satellite-based daily Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks climate data record (PERSIANN-CDR) using the Google Earth Engine (GEE) web-based API platform to investigate the spatio-temporal fluctuations and inter-annual variability of rainfall in the study domain. Several statistical indices were employed to check the data similarity between observed and remotely sensed data products and applied to each district. Moreover, non-parametric techniques, i.e., Mann–Kendall (MK) and Sen's slope estimator were applied to measure the long-term spatio-temporal trends. Remotely sensed data products reveal 422.50 mm (CHIRPS) and 571.08 mm (PERSIANN-CDR) mean annual rainfall in central Punjab. Maximum mean rainfall was witnessed during the monsoon season (70.5%), followed by pre-monsoon (15.2%) and winter (10.2%). Monthly exploration divulges that maximum mean rainfall was noticed in July (26.5%), and the minimum was in November (0.84%). The district-wise rainfall estimation shows maximum rainfall in Sialkot (931.4 mm) and minimum in Pakpattan (289.2 mm). Phase-wise analysis of annual, seasonal, and monthly trends demonstrated a sharp decreasing trend in Phase-1, averaging 3.4 mm/decade and an increasing tendency in Phase-2, averaging 9.1 mm/decade. Maximum seasonal rainfall decreased in phase-1 and increased Phase-2 during monsoon season, averaging 2.1 and 4.7 mm/decade, whereas monthly investigation showed similar phase-wise tendencies in July (1.1 mm/decade) and August (2.3 mm/decade). In addition, as district-wise analyses of annual, seasonal, and monthly trends in the last four decades reveal, the maximum declined trend was in Sialkot (18.5 mm/decade), whereas other districts witnessed an overall increasing trend throughout the years. Out of them, Gujrat district experienced the maximum increasing trend in annual terns (50.81 mm/decade), and Faisalabad (25.45 mm/decade) witnessed this during the monsoon season. The uneven variability and trends have had a crucial imprint on the local environment, mainly in the primary activities. [ABSTRACT FROM AUTHOR]

In this work, an NaYF4:Ho3+/Yb3+ upconversion phosphor in colloidal form was synthesized and then its suitability for image contrast enhancement in optical coherence tomography (OCT) and photothermal (PT) OCT imaging was analysed. A prepared sample showed intense upconversion emission in the green region (541 nm) due to the 5F4(5S2) → 5I8 transition of the Ho3+ ion. The colloidal stability of the particles was tested in several organic media and the best stability of the particles was found in dimethylformamide (DMF) medium. The applicability of the prepared particles is also demonstrated for temperature sensing, fingerprint detection, and security ink. [ABSTRACT FROM AUTHOR]

Oral submucous fibrosis (OSF) is a chronic scarring and progressive condition affecting the oral cavity, oropharynx and upper portion (1/3rd) of the esophagus. It is a potentially malignant disorder. It usually presents with trismus as the chronicity progresses with a pal presentation of the mucosa. Encountering a whitish patch, ulcer or a growth in the bed of Oral submucous fibrosis is something thought provoking. The malignant transformation potential of Oral submucous fibrosis is comparatively higher than other premalignant conditions affecting oral cavity. The need for biopsy at any stage of OSF is a necessity to rule out underlying pathogenicity to transform towards malignancy or dysplasia. [ABSTRACT FROM AUTHOR]