The role of electron and phonon temperatures in the helicity-independent all-optical switching of GdFeCo

Ultrafast optical heating of the electrons in ferrimagnetic metals can result in all-optical switching (AOS) of the magnetization. Here we report quantitative measurements of the temperature rise of GdFeCo thin films during helicity-independent AOS. Critical switching fluences are obtained as a function of the initial temperature of the sample and for laser pulse durations from 55 fs to 15 ps. We conclude that non-equilibrium phenomena are necessary for helicity-independent AOS, although the peak electron temperature does not play a critical role. Pump-probe time-resolved experiments show that the switching time increases as the pulse duration increases, with 10 ps pulses resulting in switching times of ~sim 13 ps. These results raise new questions about the fundamental mechanism of helicity-independent AOS.Comment: 18 pages, 6 figures and supplementary material

Nanomedicine modulation of endothelial low-density lipoprotein receptor-related protein 1 at the blood brain barrier for Alzheimer's disease therapy

This study introduces an innovative therapeutic concept for Alzheimer’s disease, which involves the use of nano multivalent scaffolds functionalized with peptides that specifically target low - density lipoprotein receptor - related protein 1 (LRP1) receptors. These scaffolds are engineered to interact with transport receptors at the blood - brain barrier. These nano multivalent platforms interact with LRP1 receptors in a highly specific manner, thereby significantly enhancing LRP1 - PACSIN2 - mediated transcytosis across the endothelial cells of the barrier. Experimental results from Alzheimer’s disease model mice demonstrate that this therapeutic approach effectively decreases amyloid - β accumulation and substantially ameliorates cognitive function. It has been demonstrated that these cognitive improvements persist throughout the remaining lifespan of the treated mice. This research introduces a novel drug design methodology combining multivalent targeting with membrane trafficking regulation, thereby establishing a unique therapeutic paradigm. Furthermore, the study underscores the blood - brain barrier’s indispensable contribution to the pathogenesis of Alzheimer’s disease and highlights the importance of LRP1 - mediated amyloid - β clearance

Research to establish ecological standards for water resources developments.

Three levels of development were identified to represent the environmental condition of the region under consideration. The least disturbed environments are designated as level I areas to which the strictest ecological standards is assigned to preserve and protect natural environment. The level II areas are designated by an intermediate level of human involvement in the ecological communities. Areas where large concentrations of population are located are designated as level III environments and the standards applied to these areas should be more tolerant of pollutants in the ecological systems.It is not intended that these four indicators be exhaustive; users should feel free to employ additional indicators for their study area. All the estimates of the indicator are transformed into their corresponding indicator performance level by comparing it with the maximum value in the region. They are then weighted in proportion to their relative importance.The system to establish ecological standards for water resources developments has been developed in this study. Two steps were undertaken to establish ecological standards. The first one is the categorization of development levels of natural environment by measuring specific socio-economic factors which are capable of delineating the human modification of the ecological standards in response to various development levels so as to reflect the human influence on the ecological system.Three different scales (X-axis) were proportionally developed for each of the twelve parameters reflecting the three levels of restriction. Formulas were also developed for calculating the parameter estimates. The parameter estimate obtained can be applied to the appropriate scale of a study region whose level of development was previously determined from its socio-economic evaluation. By interpolation, the ecological performance of a parameter in a study region can be derived.The validation of the methodology is accomplished by using data from the Mid-Arkansas River Basin, including Pawnee, Creek, Tulsa, and Osage counties of Oklahoma.Four socio-economic indicators were proposed to quantitatively measure the degree of human involvement in the natural environment: inhabitance index, land value, intensity of water use, and transportation facility. Inhabitance index is an indicator that explains the development level in terms of population size and settlement pattern. It is defined as the result of total population density multiplied by rural population density. Average land value (in dollars per acre) is a significant indicator of the development level of a region because the higher the development level, the more people compete for land, thus, giving rise to higher land values. The indicator of intensity of water use is expressed in terms of domestic, municipal and industrial water use (in acre-feet/sq mile-year). Because the inadequacy of transportation facilities presents great limitations to land resources development, transportation facilities (miles of streets and highways per acre) can be a significant indicator.Twelve parameters were employed to assess the ecological performance of the natural environment. For each parameter, a parameter function graph was developed, which illustrates the relationship between the parameter estimate (X-axis) and ecological performance (Y-axis). A measuring scale was set up to determine how well each parameter performs. This scale ranges from -1 to 0 and from 0 to +1. A zero value is designated as the standard value, while -1 and +1 represent the extremely poor and excellent performances respectively.The indicator performance levels are multiplied by their relative weights to obtain the weighted indicator performance levels which are then summed to obtain the development level estimates. The cutoff points on these development level estimates are determined to differentiate level I, II, and III regions

Ranking-aware Uncertainty for Text-guided Image Retrieval

Text-guided image retrieval is to incorporate conditional text to better capture users' intent. Traditionally, the existing methods focus on minimizing the embedding distances between the source inputs and the targeted image, using the provided triplets $\langle$source image, source text, target image$\rangle$. However, such triplet optimization may limit the learned retrieval model to capture more detailed ranking information, e.g., the triplets are one-to-one correspondences and they fail to account for many-to-many correspondences arising from semantic diversity in feedback languages and images. To capture more ranking information, we propose a novel ranking-aware uncertainty approach to model many-to-many correspondences by only using the provided triplets. We introduce uncertainty learning to learn the stochastic ranking list of features. Specifically, our approach mainly comprises three components: (1) In-sample uncertainty, which aims to capture semantic diversity using a Gaussian distribution derived from both combined and target features; (2) Cross-sample uncertainty, which further mines the ranking information from other samples' distributions; and (3) Distribution regularization, which aligns the distributional representations of source inputs and targeted image. Compared to the existing state-of-the-art methods, our proposed method achieves significant results on two public datasets for composed image retrieval

The finite basis problem for additively idempotent semirings of order four, I

We study the finite basis problem for 4-element additively idempotent semirings whose additive reducts are semilattices of height 1. Up to isomorphism, there are 58 such algebras. We show that 49 of them are finitely based and the remaining ones are nonfinitely based.Comment: 30page

PaTeCon: A Pattern-Based Temporal Constraint Mining Method for Conflict Detection on Knowledge Graphs

Temporal facts, the facts for characterizing events that hold in specific time periods, are attracting rising attention in the knowledge graph (KG) research communities. In terms of quality management, the introduction of time restrictions brings new challenges to maintaining the temporal consistency of KGs and detecting potential temporal conflicts. Previous studies rely on manually enumerated temporal constraints to detect conflicts, which are labor-intensive and may have granularity issues. We start from the common pattern of temporal facts and constraints and propose a pattern-based temporal constraint mining method, PaTeCon. PaTeCon uses automatically determined graph patterns and their relevant statistical information over the given KG instead of human experts to generate time constraints. Specifically, PaTeCon dynamically attaches class restriction to candidate constraints according to their measuring scores.We evaluate PaTeCon on two large-scale datasets based on Wikidata and Freebase respectively. The experimental results show that pattern-based automatic constraint mining is powerful in generating valuable temporal constraints.Comment: Accepted by AAAI2

AVNP2 protects against cognitive impairments induced by C6 glioma by suppressing tumour associated inflammation in rats

© 2020 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/).Glioblastoma is a kind of malignant tumour and originates from the central nervous system. In the last century, some researchers and clinician have noticed that the psychosocial and neurocognitive functioning of patients with malignant gliomas can be impaired. Many clinical studies have demonstrated that part of patients, adults or children, diagnosed with glioblastoma will suffer from cognitive deficiency during their clinical course, especially in long-term survivors. Many nanoparticles (NPs) can inhibit the biological functions of tumours by modulating tumour-associated inflammation, which provokes angiogenesis and tumour growth. As one of the best antiviral nanoparticles (AVNPs), AVNP2 is the 2nd generation of AVNP2 that have been conjugated to graphite-graphene for improving physiochemical performance and reducing toxicity. AVNP2 inactivates viruses, such as the H1N1 and H5N1influenza viruses and even the SARS coronavirus, while it inhibits bacteria, such as MRSA and E. coli. As antimicrobials, nanoparticles are considered to be one of the vectors for the administration of therapeutic compounds. Yet, little is known about their potential functionalities and toxicities to the neurotoxic effects of cancer. Herein, we explored the functionality of AVNP2 on inhibiting C6 in glioma-bearing rats. The novel object-recognition test and open-field test showed that AVNP2 significantly improved the neuro-behaviour affected by C6 glioma. AVNP2 also alleviated the decline of long-term potentiation (LTP) and the decreased density of dendritic spines in the CA1 region induced by C6. Western blot assay and immunofluorescence staining showed that the expressions of synaptic-related proteins (PSD-95 and SYP) were increased, and these findings were in accordance with the results mentioned above. It revealed that the sizes of tumours in C6 glioma-bearing rats were smaller after treatment with AVNP2. The decreased expression of inflammatory factors (IL-1β, IL-6 and TNF-α) by Western blotting assay and ELISA, angiogenesis protein (VEGF) by Western blotting assay and other related proteins (BDNF, NF-ĸB, iNOS and COX-2) by Western blotting assay in peri-tumour tissue indicated that AVNP2 could control tumour-associated inflammation, thus efficiently ameliorating the local inflammatory condition and, to some extent, inhibiting angiogenesis in C6-bearing rats. In conclusion, our results suggested that AVNP2 could have an effect on the peri-tumor environment, obviously restraining the growth progress of gliomas, and eventually improving cognitive levels in C6-bearing rats.Peer reviewedProo