After posing the axiom of linear algebra, the author develops how this allows the calculation of arbitrary base powers, which provides an instantaneous calculation of powers in a particular base such as base ten;first...After posing the axiom of linear algebra, the author develops how this allows the calculation of arbitrary base powers, which provides an instantaneous calculation of powers in a particular base such as base ten;first of all by developing the any base calculation of these powers, then by calculating triangles following the example of the “arithmetical” triangle of Pascal and showing how the formula of the binomial of Newton is driving the construction. The author also develops the consequences of the axiom of linear algebra for the decimal writing of numbers and the result that this provides for the calculation of infinite sums of the inverse of integers to successive powers. Then the implications of these new forms of calculation on calculator technologies, with in particular the storage of triangles which calculate powers in any base and the use of a multiplication table in a very large canonical base are discussed.展开更多
Background:Taxus cuspidata S.et Z.is a precious species of frigid zone plant belonging to the Taxaceae family,which possesses anticancer,anti-inflammatory,hypoglycemic,and antibacterial pharmacological properties.Whil...Background:Taxus cuspidata S.et Z.is a precious species of frigid zone plant belonging to the Taxaceae family,which possesses anticancer,anti-inflammatory,hypoglycemic,and antibacterial pharmacological properties.While taxane extracted from Taxus chinensis has been reported to elicit antioxidant activities,whether Taxus cuspidata S.et Z.has skin-protective actions against injuries remained unknown.This study aims to explore the pharmacological effects of three Taxus extracts on skin melanin deposition,oxidation,inflammation,and allergy so as to provide new ideas for the prevention and treatment of various diseases related to skin damage.Methods:Skin melanin deposition was evaluated by measuring melanin content in the skin of guinea pigs by alkali lysis method.Antioxidant capacity was evaluated by measuring superoxide dismutase(SOD)concentration and glutathione(GSH)content in skin tissue homogenates of Kunming mice by SOD assay kit and micro reduced GSH assay kit.The quantitative real-time polymerase chain reaction(qRT-PCR)and western blotting were used to examine the levels of both SOD and recombinant glutathione peroxidase 4(GPX4).Skin inflammation was evaluated by xylene-induced ear swelling test and egg-white-induced paw swelling test in mice.In a mouse model of skin allergy induced by 4-aminopyridine(4-AP),allergy was determined by licking body counts and histamine concentrations in tissue homogenates using enzyme-linked immunosorbent assay(ELISA)kits.Two proinflammatory factors tumor necrosis factor(TNF)-αand interleukin(IL)-1βwere measured by qRT-PCR.Hematoxylin and eosin(HE)staining was conducted to assess the degree of skin lesion.Results:All three Taxus extracts including Taxus chinensis essential oil,Taxus chinensis extract and Taxus chinensis extract compound reduced the melanin deposits in the back skin relative to the non-treated control animals,of which Taxus chinensis essential oil produced the greatest effect.In contrast,the three Taxus extracts elevated SOD and GSH levels in the skin tissues,and the highest increase was seen with Taxus chinensis essential oil.Three Taxus extracts,especially Taxus chinensis essential oil,effectively reduce the rate of ear and paw swelling.All three Taxus extracts reduced the number of body licks,the levels of TNF-αand IL-1β,and the histamine content in tissue homogenates of mice and alleviated skin damage.Consistently,Taxus chinensis essential oil yielded the greatest magnitude of decreases.Conclusion:While all three Taxus extracts possessed the anti-skin melanin deposition,oxidation,and allergy properties,Taxus chinensis essential oil produced the superior effects.展开更多
To harness abundant and clean solar energy along with relieving energy and environmental issues,photocatalysis holds great promise.Semiconductor-based photocatalysts are crucial to its successful application.However,t...To harness abundant and clean solar energy along with relieving energy and environmental issues,photocatalysis holds great promise.Semiconductor-based photocatalysts are crucial to its successful application.However,the photocatalytic efficiency based on a unitary semiconductor material falls short of expectations,mainly because of the rapid recombination of photogenerated electrons and holes.This originates in the extremely strong Columbic force between them.Moreover,it is impossible for a single photocatalyst to achieve wide light absorption and ample redox ability concurrently.展开更多
It is not clear whether the method used in functional brain-network related research can be applied to explore the feature binding mechanism of visual perception. In this study, we inves-tigated feature binding of col...It is not clear whether the method used in functional brain-network related research can be applied to explore the feature binding mechanism of visual perception. In this study, we inves-tigated feature binding of color and shape in visual perception. Functional magnetic resonance imaging data were collected from 38 healthy volunteers at rest and while performing a visual perception task to construct brain networks active during resting and task states. Results showed that brain regions involved in visual information processing were obviously activated during the task. The components were partitioned using a greedy algorithm, indicating the visual network existed during the resting state.Z-values in the vision-related brain regions were calculated, conifrming the dynamic balance of the brain network. Connectivity between brain regions was determined, and the result showed that occipital and lingual gyri were stable brain regions in the visual system network, the parietal lobe played a very important role in the binding process of color features and shape features, and the fusiform and inferior temporal gyri were crucial for processing color and shape information. Experimental ifndings indicate that understanding visual feature binding and cognitive processes will help establish computational models of vision, improve image recognition technology, and provide a new theoretical mechanism for feature binding in visual perception.展开更多
Artificial Z(S)-scheme photocatalytic water splitting systems have attracted extensive attention due to their advantages such as wide light absorption range,high charge separation efficiency and strong carrier redox a...Artificial Z(S)-scheme photocatalytic water splitting systems have attracted extensive attention due to their advantages such as wide light absorption range,high charge separation efficiency and strong carrier redox ability.However,it is still challenging to design and prepare Z(S)-scheme photocatalysts with low-cost and highly stability for efficiently photocatalytic overall water splitting using solar energy.This review mainly introduces various strategies to improve the photocatalytic water splitting performance of Z(S)-scheme systems.These strategies mainly focus on enhancing or extending the range of light absorption,promoting charge separation,and enhancing surface redox reaction in Z(S)-scheme systems.Finally,the main challenges of Z(S)-scheme photocatalytic water splitting systems and their future development directions are pointed out.This review would be beneficial to understanding the challenges and opportunities faced by the research field of Z(S)-scheme photocatalytic systems,and has important guiding significance for the development and utilization of high-performance Z(S)-scheme photocatalytic reaction system in the future.展开更多
The polymeric chalcogenide [W2O2S6Cu4(NCMe)4]n (compound 1) was synthesized by the self-assembly reaction of (NH4)2(WOS3) with CuBr in MeCN in the presence of tricyclohexylphosphane (PCy3) under a purified nitrogen at...The polymeric chalcogenide [W2O2S6Cu4(NCMe)4]n (compound 1) was synthesized by the self-assembly reaction of (NH4)2(WOS3) with CuBr in MeCN in the presence of tricyclohexylphosphane (PCy3) under a purified nitrogen atmosphere using standard Schlenk techniques. It gives rise to a novel 1D polymeric compound 1 with solvent MeCN coordinated to the copper atom. This situation is unprecedented in the W(Mo)/Cu/S system. The crystals were characterized by elemental analysis, IR and single-crystal X-ray crystallography. The configuration of the polymeric compound can be viewed as a helical chain which is propagated along the crystallographic c axis. The excited state absorption and refraction of compound 1 in CH3CN solution were studied by using the Z-scan technique with laser pulses of 40 ps pulse-width at a wavelength of 532 nm. The polymeric compound possesses an optical self-focusing performance. The positive nonlinear refraction is attributed to population transitions between singlet states. Compound 1 displays a strong excited-state absorption.展开更多
Textbooks on phonology and on teaching ESL （English as a Second Language） often present the place of articulation of the sibilant/s/and its voiced counterpart/z/as a settled matter. The/s/and/z/are described and lis...Textbooks on phonology and on teaching ESL （English as a Second Language） often present the place of articulation of the sibilant/s/and its voiced counterpart/z/as a settled matter. The/s/and/z/are described and listed in phonological charts as ＂alveolar fricatives＂, meaning that the tongue is raised and the apex approaches the alveolar ridge. Those teaching pronunciation or remediating speech problems often use these descriptions by the IPA （International Phonetic Association） as models for teaching these phonemes. A number of linguists and instructors, however, have suggested that an acceptable/s/and/z/sound can be produced in English by other means This study attempted to determine the prevalence of the acceptable alternative placements for the/s/and/z/sounds in a sample of 50 English-speaking university students. Results revealed that 64% of participants used alternate tongue positions to that described in the literature as standard. Implications for speech pathology and ESL instruction are discussed.展开更多
文摘After posing the axiom of linear algebra, the author develops how this allows the calculation of arbitrary base powers, which provides an instantaneous calculation of powers in a particular base such as base ten;first of all by developing the any base calculation of these powers, then by calculating triangles following the example of the “arithmetical” triangle of Pascal and showing how the formula of the binomial of Newton is driving the construction. The author also develops the consequences of the axiom of linear algebra for the decimal writing of numbers and the result that this provides for the calculation of infinite sums of the inverse of integers to successive powers. Then the implications of these new forms of calculation on calculator technologies, with in particular the storage of triangles which calculate powers in any base and the use of a multiplication table in a very large canonical base are discussed.
基金funded by the following grants, including the Key Research and Development Program of Shaanxi Province (No. 2023-LL-QY-42)the Xi'an University of Architecture and Technology Research Initiation Grant Program (No. 1960323102)the Xi'an University of Architecture and Technology Special Program for Cultivation of Frontier Interdisciplinary Fields (No. 1960523142)。
基金This work was supported by the National Natural Science Foundation of Heilongjiang Province-Outstanding Youth Project(No.YQ2020H008).
文摘Background:Taxus cuspidata S.et Z.is a precious species of frigid zone plant belonging to the Taxaceae family,which possesses anticancer,anti-inflammatory,hypoglycemic,and antibacterial pharmacological properties.While taxane extracted from Taxus chinensis has been reported to elicit antioxidant activities,whether Taxus cuspidata S.et Z.has skin-protective actions against injuries remained unknown.This study aims to explore the pharmacological effects of three Taxus extracts on skin melanin deposition,oxidation,inflammation,and allergy so as to provide new ideas for the prevention and treatment of various diseases related to skin damage.Methods:Skin melanin deposition was evaluated by measuring melanin content in the skin of guinea pigs by alkali lysis method.Antioxidant capacity was evaluated by measuring superoxide dismutase(SOD)concentration and glutathione(GSH)content in skin tissue homogenates of Kunming mice by SOD assay kit and micro reduced GSH assay kit.The quantitative real-time polymerase chain reaction(qRT-PCR)and western blotting were used to examine the levels of both SOD and recombinant glutathione peroxidase 4(GPX4).Skin inflammation was evaluated by xylene-induced ear swelling test and egg-white-induced paw swelling test in mice.In a mouse model of skin allergy induced by 4-aminopyridine(4-AP),allergy was determined by licking body counts and histamine concentrations in tissue homogenates using enzyme-linked immunosorbent assay(ELISA)kits.Two proinflammatory factors tumor necrosis factor(TNF)-αand interleukin(IL)-1βwere measured by qRT-PCR.Hematoxylin and eosin(HE)staining was conducted to assess the degree of skin lesion.Results:All three Taxus extracts including Taxus chinensis essential oil,Taxus chinensis extract and Taxus chinensis extract compound reduced the melanin deposits in the back skin relative to the non-treated control animals,of which Taxus chinensis essential oil produced the greatest effect.In contrast,the three Taxus extracts elevated SOD and GSH levels in the skin tissues,and the highest increase was seen with Taxus chinensis essential oil.Three Taxus extracts,especially Taxus chinensis essential oil,effectively reduce the rate of ear and paw swelling.All three Taxus extracts reduced the number of body licks,the levels of TNF-αand IL-1β,and the histamine content in tissue homogenates of mice and alleviated skin damage.Consistently,Taxus chinensis essential oil yielded the greatest magnitude of decreases.Conclusion:While all three Taxus extracts possessed the anti-skin melanin deposition,oxidation,and allergy properties,Taxus chinensis essential oil produced the superior effects.
文摘To harness abundant and clean solar energy along with relieving energy and environmental issues,photocatalysis holds great promise.Semiconductor-based photocatalysts are crucial to its successful application.However,the photocatalytic efficiency based on a unitary semiconductor material falls short of expectations,mainly because of the rapid recombination of photogenerated electrons and holes.This originates in the extremely strong Columbic force between them.Moreover,it is impossible for a single photocatalyst to achieve wide light absorption and ample redox ability concurrently.
基金financially supported by grants from the National Natural Science Foundation of China,No.61170136,61373101,61472270,and 61402318Natural Science Foundation(Youth Science and Technology Research Foundation)of Shanxi Province,No.2014021022-5Shanxi Provincial Key Science and Technology Projects(Agriculture),No.20130311037-4
文摘It is not clear whether the method used in functional brain-network related research can be applied to explore the feature binding mechanism of visual perception. In this study, we inves-tigated feature binding of color and shape in visual perception. Functional magnetic resonance imaging data were collected from 38 healthy volunteers at rest and while performing a visual perception task to construct brain networks active during resting and task states. Results showed that brain regions involved in visual information processing were obviously activated during the task. The components were partitioned using a greedy algorithm, indicating the visual network existed during the resting state.Z-values in the vision-related brain regions were calculated, conifrming the dynamic balance of the brain network. Connectivity between brain regions was determined, and the result showed that occipital and lingual gyri were stable brain regions in the visual system network, the parietal lobe played a very important role in the binding process of color features and shape features, and the fusiform and inferior temporal gyri were crucial for processing color and shape information. Experimental ifndings indicate that understanding visual feature binding and cognitive processes will help establish computational models of vision, improve image recognition technology, and provide a new theoretical mechanism for feature binding in visual perception.
基金financially supported by the Natural Science Foundation of China(Nos.22202065,51902101)the Youth Natural Science Foundation of Hunan Province(No.2021JJ40044)+2 种基金Natural Science Foundation of Jiangsu Province(No.BK20201381)Science Foundation of Nanjing University of Posts and Telecommunications(Nos.NY219144,NY221046)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.SJCX23_0262)。
文摘Artificial Z(S)-scheme photocatalytic water splitting systems have attracted extensive attention due to their advantages such as wide light absorption range,high charge separation efficiency and strong carrier redox ability.However,it is still challenging to design and prepare Z(S)-scheme photocatalysts with low-cost and highly stability for efficiently photocatalytic overall water splitting using solar energy.This review mainly introduces various strategies to improve the photocatalytic water splitting performance of Z(S)-scheme systems.These strategies mainly focus on enhancing or extending the range of light absorption,promoting charge separation,and enhancing surface redox reaction in Z(S)-scheme systems.Finally,the main challenges of Z(S)-scheme photocatalytic water splitting systems and their future development directions are pointed out.This review would be beneficial to understanding the challenges and opportunities faced by the research field of Z(S)-scheme photocatalytic systems,and has important guiding significance for the development and utilization of high-performance Z(S)-scheme photocatalytic reaction system in the future.
基金Project (2005038557) supported by the Post-Doctor Programs Foundation of Ministry of Education of China
文摘The polymeric chalcogenide [W2O2S6Cu4(NCMe)4]n (compound 1) was synthesized by the self-assembly reaction of (NH4)2(WOS3) with CuBr in MeCN in the presence of tricyclohexylphosphane (PCy3) under a purified nitrogen atmosphere using standard Schlenk techniques. It gives rise to a novel 1D polymeric compound 1 with solvent MeCN coordinated to the copper atom. This situation is unprecedented in the W(Mo)/Cu/S system. The crystals were characterized by elemental analysis, IR and single-crystal X-ray crystallography. The configuration of the polymeric compound can be viewed as a helical chain which is propagated along the crystallographic c axis. The excited state absorption and refraction of compound 1 in CH3CN solution were studied by using the Z-scan technique with laser pulses of 40 ps pulse-width at a wavelength of 532 nm. The polymeric compound possesses an optical self-focusing performance. The positive nonlinear refraction is attributed to population transitions between singlet states. Compound 1 displays a strong excited-state absorption.
文摘Textbooks on phonology and on teaching ESL （English as a Second Language） often present the place of articulation of the sibilant/s/and its voiced counterpart/z/as a settled matter. The/s/and/z/are described and listed in phonological charts as ＂alveolar fricatives＂, meaning that the tongue is raised and the apex approaches the alveolar ridge. Those teaching pronunciation or remediating speech problems often use these descriptions by the IPA （International Phonetic Association） as models for teaching these phonemes. A number of linguists and instructors, however, have suggested that an acceptable/s/and/z/sound can be produced in English by other means This study attempted to determine the prevalence of the acceptable alternative placements for the/s/and/z/sounds in a sample of 50 English-speaking university students. Results revealed that 64% of participants used alternate tongue positions to that described in the literature as standard. Implications for speech pathology and ESL instruction are discussed.
