356 research outputs found
Radioactivity and heavy metal concentrations and assessment of hazard indices in sediments from Zhushan Bay at Taihu Lake, China
Combinatorial administration of insulin and vitamin C alleviates the cerebral vasospasm after experimental subarachnoid hemorrhage in rabbit
<p>Abstract</p> <p>Background</p> <p>Cerebral vasospasm (CVS) is a common serious complication after the spontaneous subarachnoid hemorrhage (SAH). Despite recent advances in medical and surgical treatments, the 30-day mortality rate of SAH remains high, and there is lack of especially effective clinical treatment to alleviate and improve CVS. The present study has investigated the therapeutic effect of insulin and vitamin C on CVS after SAH.</p> <p>Results</p> <p>Five days after SAH, there is obvious basilar artery spasm in SAH group, whose average vascular cross-sectional area (233,099 ± 16,750 Όm<sup>2</sup>) is significantly smaller than that in control group (462,128 ± 74,756 Όm<sup>2</sup>), which is also significantly different from those in SAH + insulin group (221,114 ± 43,457 Όm<sup>2</sup>) and SAH + vitamin C group (237,820 ± 21,703 Όm<sup>2</sup>). SAH + insulin + vitamin C group shows no evident vasospasm and maintains a vascular cross-sectional area of 425,530 ± 45,503 Όm<sup>2</sup>, which is significantly different from that in SAH group. Insulin receptor α (InRα) expression is significantly downregulated in the vascular endothelial cells of SAH, SAH + insulin, and SAH + vitamin C groups (<it>P </it>< 0.01) but remains unchanged in vascular endothelial cells of SAH + insulin + vitamin C group (<it>P </it>> 0.05). Five days after SAH, serum and cerebrospinal fluid NO levels in SAH, SAH + insulin, and SAH + vitamin C groups decrease significantly (<it>P </it>< 0.01) compared to that in control group, whereas the reduction is not evident in SAH + insulin + vitamin C group (<it>P </it>> 0.05).</p> <p>Conclusion</p> <p>Combinatorial treatment with insulin and vitamin C has effectively relieved the CVS after SAH in rabbit, possibly through increasing the InRα expression and NO level, whereas treatment with insulin or vitamin C alone fails to do so.</p
Comparison of three magnetization transfer ratio parameters for assessment of intestinal fibrosis in patients with Crohnâs disease
Special Libraries, January 1925
Volume 16, Issue 1https://scholarworks.sjsu.edu/sla_sl_1925/1000/thumbnail.jp
Relating Biomass and Leaf Area Index to Non-destructive Measurements in Order to Monitor Changes in Arctic Vegetation
This paper reports an alternative method for seasonal and long-term monitoring of biomass and the leaf area index (LAI) at Arctic tundra sites. Information related to the historical and projected change in abundance and distribution of biomass and LAI is required to address numerous environmental and resource management issues. Observations of earth from satellites could potentially be used to derive seasonal and long-term changes in biomass and the LAI. To realize this potential, seasonal and long-term ground monitoring data for validation are essential; however, the conventional destructive sampling method for measuring biomass and the LAI does not allow repetitive measurements at the same plots and thus is not suitable for monitoring change over time. Alternative methods, such as sampling nearby similar plots, can be laborious and easily subject to large sampling errors, especially in Arctic tundra sites with low vegetation cover. In this study, we developed a practical method for relating non-destructive measurements (percent cover and mean height) to biomass and the LAI for 13 major Arctic plant groups, or seven plant functional types, on the basis of measurements at 196 plots across Canadaâs Arctic tundra ecosystems. Using the method at the plant group level to estimate plot total vascular aboveground biomass, foliage biomass, and LAI, we had r2 = 0.91â0.95 and relative mean absolute error of 25â29%. By this method, one could monitor seasonal and long-term changes in biomass and the LAI through repeated, non-destructive observations of percent cover and mean height at the same permanent plots.Cette communication prĂ©sente une mĂ©thode de rechange en vue de la surveillance saisonniĂšre et Ă long terme de la biomasse et de lâindice de surface foliaire (LAI) de sites de toundra de lâArctique. Afin de relever divers enjeux relatifs Ă la gestion de lâenvironnement et des ressources, il faut recueillir des donnĂ©es se rapportant au changement historique et projetĂ© en matiĂšre dâabondance et de rĂ©partition de la biomasse et du LAI. On pourrait Ă©ventuellement recourir aux observations de la Terre Ă partir de satellites afin de dĂ©celer les changements saisonniers et Ă long terme caractĂ©risant la biomasse et le LAI. Pour en arriver lĂ , il est essentiel de disposer de donnĂ©es saisonniĂšres et Ă long terme au sol Ă des fins de validation. Cependant, la mĂ©thode dâĂ©chantillonnage destructeur classique permettant de mesurer la biomasse et le LAI ne permettent pas la prise de mesures rĂ©pĂ©titives aux mĂȘmes sites et par consĂ©quent, elle ne convient pas Ă la surveillance du changement qui sâexerce au fil du temps. Dâautres mĂ©thodes, telles que lâĂ©chantillonnage de sites semblables dans les environs, peuvent sâavĂ©rer laborieuses et facilement faire lâobjet dâimportantes erreurs dâĂ©chantillonnage, surtout aux sites de toundra de lâArctique dont la couverture vĂ©gĂ©tale est basse. Dans le cadre de cette Ă©tude, nous avons mis au point une mĂ©thode pratique pour Ă©tablir un rapport entre les mesures non destructives (pourcentage de couverture et hauteur moyenne) et la biomasse et le LAI de 13 groupes vĂ©gĂ©taux importants de lâArctique, ou sept types vĂ©gĂ©taux fonctionnels en fonction de la mesure de 196 sites Ă la grandeur des Ă©cosystĂšmes de toundra de lâArctique canadien. En nous appuyant sur la mĂ©thode des groupes vĂ©gĂ©taux pour estimer la biomasse vasculaire totale Ă ciel ouvert des sites, la biomasse foliaire et le LAI, nous avions r2 = 0,91â0,95 et une erreur absolue relative moyenne de 25 Ă 29%. Au moyen de cette mĂ©thode, il serait possible de surveiller les changements saisonniers et Ă long terme en matiĂšre de biomasse et de LAI grĂące Ă des observations rĂ©pĂ©tĂ©es et non destructives du pourcentage de la couverture et de la hauteur moyenne aux mĂȘmes sites permanents
Brick tea consumption and its relationship with fluorosis in Tibetan areas
Brick tea-type fluorosis (BTF) due to a high intake of brick tea is possible in Tibetan populations, and dental fluorosis (DF) and skeletal fluorosis (SF) are its primary manifestations. To determine the prevalence of DF and SF and their relationships with brick tea intake in Tibetan populations, a literature review was conducted for studies published between 1994 and 2021. The available evidence revealed that brick tea may be produced from older stems and leaves of the tea plant and that the fluoride content of brick tea exceeds the national standard. The harsh environment of the plateau has led to limited food sources for the local Tibetan people who form the habit of drinking tea leaves as a satiation solution to digest greasy food and replenish vitamins, and regular consumption of brick tea leads to excessive exposure of Tibetan residents to fluoride. Studies in Tibet showed that the prevalence of DF in children was 14.06â75.93% in different districts, and the overall pooled prevalence of DF was 26.08%. The prevalence of SF in adults was 19.90â74.77% in different Tibetan districts, and the overall pooled prevalence of SF was 33.84%. The analysis of risk factors showed that the prevalence of BTF may be related to high-altitude and different working and living conditions, and BTF in children may be associated with fluoride intake during mothersâ pregnancy and lactation. With the development of bioinformatics research, gene polymorphisms were suspected to be related to susceptibility to fluorosis in Tibetan populations. The study of BTF in Tibetan people needs to be further investigated and standardized, and additional studies evaluating the pathogenesis and preventive measures of BTF are warranted
Protein/polysaccharide intramolecular electrostatic complex as superior food-grade foaming agent
High-performance foaming agents are widely required in the food industry. In this study, the relationship between electrostatic interaction of whey protein isolate (WPI)/alginate (ALG) and the resultant foaming properties were investigated systematically. The phase diagram of WPI/ALG was established in terms of protein/polysaccharide mixing ratio (r) and pH. The results show that the foaming capacity of WPI/ALG complexes is almost the same across different regions of the phase
diagram, while the foam stability varies significantly. At pHs 7.0 and 0.5 where no electrostatic complexation occurs, the foam stability is found to decrease monotonically with decreasing r. At pH 4.0 and particular mixing ratios, i.e., r = 1 and 2, intramolecular soluble complexes are formed and the particular WPI/ALG complexes yield the best foam stability, as compared to other electrostatic complexes or individual components. The half-life (t1/2) of the foams stabilized by the intramolecular electrostatic complexes is as long as 4000 s at a very low WPI/ALG concentration of 0.1% w/w. The foaming properties are in line with the foam viscosity, interfacial adsorption behavior and
microstructures of the complexes observed at the air-water interface. This demonstrates that the protein/polysaccharide intramolecular electrostatic complex, more specifically at the stoichiometry, could potentially act as a superior foaming agent in the food industry
Stabilizing Cu in Cu/SiO Catalysts with a Shattuckite-Like Structure Boosts CO2 Hydrogenation into Methanol
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Adaptive robust blind watermarking scheme improved by entropy-based SVM and optimized quantum genetic algorithm
With the intensive study of machine learning in digital watermarking, its ability to balance the robustness and transparency of watermarking technology has attracted researchersâ attention. Therefore, quantum genetic algorithm, which serves as an intelligent optimized scheme combined with biological genetic mechanism and quantum computing, is widely used in various fields. In this study, an adaptive robust blind watermarking algorithm by means of optimized quantum genetics (OQGA) and entropy classification-based SVM (support vector machine) is proposed. The host image was divided into two parts according to the odd and even rows of the host image. One part was transformed by DCT (discrete cosine transform), and then the embedding intensity and position were separately trained by entropy-based SVM and OQGA; the other part was by DWT (discrete wavelet transform), in which the key fusion was achieved by an ergodic matrix to embed the watermark. Simulation results indicate the proposed algorithm ensures the watermark scheme transparency as well as having better resistance to common attacks such as lossy JPEG compression, image darken, Gaussian low-pass filtering, contrast decreasing, salt-pepper noise, and geometric attacks such as rotation and cropping.
Received
22 May 2019
Revised
18 Aug 2019
Accepted
17 Sep 2019
Published
28 Oct 201
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Black-Box watermarking and blockchain for IP protection of voiceprint recognition model
Deep neural networks are widely used for voiceprint recognition, whilst voiceprint recognition models are vulnerable to attacks. Existing protection schemes for voiceprint recognition models are insufficient to withstand various robustness attacks and cannot prevent model theft. This paper proposes a black-box voiceprint recognition model protection framework that combines active and passive protection. It embeds key information into the Mel spectrogram to generate trigger samples that are difficult to detect and remove and injects them into the host model as watermark W, thereby enhancing the copyright protection performance of the voiceprint recognition model. To restrict the use of the model by unauthorized users, the index number corresponding to the model and the encrypted model information are stored on the blockchain, and then, an exclusive smart contract is designed to restrict access to the model. Experimental results show that this framework effectively protects voiceprint recognition model copyrights and restricts unauthorized access
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