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1.
Sci Adv ; 10(38): eadp5156, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39303032

RESUMEN

Proxy reconstructions suggest that increasing global mean sea surface temperature (GMSST) during the last deglaciation was accompanied by a comparable or greater increase in global mean ocean temperature (GMOT), corresponding to a large heat storage efficiency (HSE; ∆GMOT/∆GMSST). An increased GMOT is commonly attributed to surface warming at sites of deepwater formation, but winter sea ice covered much of these source areas during the last deglaciation, which would imply an HSE much less than 1. Here, we use climate model simulations and proxy-based reconstructions of ocean temperature changes to show that an increased deglacial HSE is achieved by warming of intermediate-depth waters forced by mid-latitude surface warming in response to greenhouse gas and ice sheet forcing as well as by reduced Atlantic meridional overturning circulation associated with meltwater forcing. These results, which highlight the role of surface warming and oceanic circulation changes, have implications for our understanding of long-term ocean heat storage change.

2.
Opt Lett ; 49(14): 3970-3973, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008753

RESUMEN

Monolayer tungsten selenide (WSe2) has attracted attention due to its direct bandgap-generated strong light emission and light-matter interaction. Herein, vertical WSe2/VOCl bilayer heterojunctions with enhanced PL of WSe2 were synthesized by the vapor growth method. The morphology, crystal structure, and chemical composition of the WSe2/VOCl heterojunctions were systematically investigated, which confirmed the successful formation of the heterojunctions. The PL emission intensity of WSe2 obtained from the WSe2/VOCl heterojunction was about 2.4 times higher than that of the WSe2 monolayer, demonstrating the high optical quality of the WSe2/VOCl heterojunction, which was further confirmed by time-resolved PL measurements. The insulator top VOCl, which was deposited on the surface of the semiconductor bottom WSe2 as a surface passivation material, reducing the impurities and resulting in an atomically clean surface, successfully enhanced the PL emission of the bottom WSe2. This vertical WSe2/VOCl bilayer heterojunction with PL enhancement could provide a promising platform for optical devices.

3.
Hum Vaccin Immunother ; 20(1): 2338980, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38898574

RESUMEN

The burden of herpes zoster (HZ) is anticipated to increase among the aging population of China over time. The knowledge, attitudes, and practices (KAP) of the population toward HZ can help inform the design of public health strategies. As there is a paucity of KAP data in China, this cross-sectional survey therefore sought to assess KAP related to HZ from the general population, patients with HZ, and dermatologists in China. The total number of respondents from the general population, HZ patients, and dermatologists were 804, 282, and 160, respectively. Notably, some gaps in knowledge regarding the severity, transmission, and prevention of HZ were identified across all groups. For example, less than half of respondents from the general population and HZ patients understood that vaccination does not treat HZ. For dermatologists, not all were aware of adverse reactions following HZ vaccination and some had misconceptions regarding the mode of transmission of HZ. Given the link between an individual's disease knowledge to their attitudes and practices, improved understanding of HZ could underlie positive attitudes and help reinforce healthcare professionals' recommendations in the management and prevention of HZ. In particular, doctors may be well-positioned to support HZ prevention initiatives, as most of the general population and HZ patients found vaccination more acceptable if recommended by a doctor (78.9% and 81.6%, respectively). Therefore, consideration of these KAP attributes may support the development of targeted educational interventions and effective public health strategies against HZ in China.


Asunto(s)
Dermatólogos , Conocimientos, Actitudes y Práctica en Salud , Herpes Zóster , Humanos , Herpes Zóster/prevención & control , Herpes Zóster/epidemiología , Estudios Transversales , China/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Adulto , Dermatólogos/psicología , Dermatólogos/estadística & datos numéricos , Anciano , Encuestas y Cuestionarios , Adulto Joven , Vacuna contra el Herpes Zóster/administración & dosificación , Vacunación/psicología , Vacunación/estadística & datos numéricos , Adolescente
4.
ACS Omega ; 9(14): 15854-15860, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38617703

RESUMEN

The porous skeleton structure of oxidizers can effectively enlarge the contact area with fuels and boost the reactivity of thermites, but the overly complex preparation processes tend to limit their use to some extent. To overcome this issue, water-soluble starch and copper nitrate were used as a template to form a carbon skeleton copper oxide (C-CuO) after spray drying and calcination. By adding nanoaluminum into the spray drying process, the n-Al@C-CuO was prepared and compared with the physically mixed n-Al/C-CuO in the context. Scanning electron microscopy and differential scanning calorimetry were used to observe the morphology and analyze the thermal process. The pressure-time test and the electrostatic sensitivity test were used to measure the energy release properties and the safety of the thermites. Results indicated that the n-Al@C-CuO had 60.97 °C earlier initial exothermic temperature and 1.74 times higher peak pressure than that of the physically mixed sample. The n-Al@C-CuO was not ignited under 25 kV in the electrostatic sensitivity test, showing the great electrostatic safety of the sample. These findings are expected to facilitate the development of spray drying and promote energy release of traditional thermites.

5.
Philos Trans A Math Phys Eng Sci ; 382(2271): 20230094, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38522461

RESUMEN

At the Royal Society meeting in 2023, we have mainly presented our lunar orbit array concept called DSL, and also briefly introduced a concept of a lunar surface array, LARAF. As the DSL concept had been presented before, in this article, we introduce the LARAF. We propose to build an array in the far side of the Moon, with a master station which handles the data collection and processing, and 20 stations with maximum baseline of 10 km. Each station consists of 12 membrane antenna units, and the stations are connected to the master station by power line and optical fibre. The array will make interferometric observation in the 0.1-50 MHz band during the lunar night, powered by regenerated fuel cells. The whole array can be carried to the lunar surface with a heavy rocket mission, and deployed with a rover in eight months. Such an array would be an important step in the long-term development of lunar-based ultralong wavelength radio astronomy. It has a sufficiently high sensitivity to observe many radio sources in the sky, though still short of the dark age fluctuations. We discuss the possible options in the power supply, data communication, deployment etc. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades (part 2)'.

6.
Microb Drug Resist ; 30(4): 175-178, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38364190

RESUMEN

Porcine contagious pleuropneumonia, caused by Actinobacillus pleuropneumoniae, has resulted in significant economic losses to the swine industry. Although antibiotics are commonly employed to control this disease, their widespread use or misuse can lead to the development of antibiotic resistance in A. pleuropneumoniae. Consequently, it is crucial to conduct antimicrobial susceptibility testing on clinical isolates. In our study, we identified one strain of A. pleuropneumoniae with resistance to florfenicol and extracted a 5919 bp plasmid named pAPPJY, which confers florfenicol resistance. Sequence analysis revealed that the plasmid contains four open reading frames, namely rep, antioxin vbha family protein, floR, and a partial copy of lysr. Although a few variations in gene position were observed, the plasmid sequence exhibits a high degree of similarity to other florfenicol-resistant plasmids found in Glaesserella parasuis and A. pleuropneumoniae. Therefore, it is possible that the pAPPJY plasmid functions as a shuttle, facilitating the spread of florfenicol resistance between G. parasuis and A. pleuropneumoniae. In addition, partial recombination may occur during bacterial propagation. In conclusion, this study highlights the horizontal transmission of antibiotic resistance among different bacterial species through plasmids, underscoring the need for increased attention to antibiotic usage.


Asunto(s)
Infecciones por Actinobacillus , Actinobacillus pleuropneumoniae , Enfermedades de los Porcinos , Tianfenicol/análogos & derivados , Animales , Porcinos , Antibacterianos/farmacología , Actinobacillus pleuropneumoniae/genética , Pruebas de Sensibilidad Microbiana , Plásmidos , Infecciones por Actinobacillus/tratamiento farmacológico , Infecciones por Actinobacillus/veterinaria , Enfermedades de los Porcinos/tratamiento farmacológico , Enfermedades de los Porcinos/microbiología
7.
Sci Bull (Beijing) ; 69(4): 473-482, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38123429

RESUMEN

The growth of data and Internet of Things challenges traditional hardware, which encounters efficiency and power issues owing to separate functional units for sensors, memory, and computation. In this study, we designed an α-phase indium selenide (α-In2Se3) transistor, which is a two-dimensional ferroelectric semiconductor as the channel material, to create artificial optic-neural and electro-neural synapses, enabling cutting-edge processing-in-sensor (PIS) and computing-in-memory (CIM) functionalities. As an optic-neural synapse for low-level sensory processing, the α-In2Se3 transistor exhibits a high photoresponsivity (2855 A/W) and detectivity (2.91 × 1014 Jones), facilitating efficient feature extraction. For high-level processing tasks as an electro-neural synapse, it offers a fast program/erase speed of 40 ns/50 µs and ultralow energy consumption of 0.37 aJ/spike. An AI vision system using α-In2Se3 transistors has been demonstrated. It achieved an impressive recognition accuracy of 92.63% within 12 epochs owing to the synergistic combination of the PIS and CIM functionalities. This study demonstrates the potential of the α-In2Se3 transistor in future vision hardware, enhancing processing, power efficiency, and AI applications.

8.
Front Optoelectron ; 16(1): 42, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38060145

RESUMEN

Dynamically engineering the optical and electrical properties in two-dimensional (2D) materials is of great significance for designing the related functions and applications. The introduction of foreign-atoms has previously been proven to be a feasible way to tune the band structure and related properties of 3D materials; however, this approach still remains to be explored in 2D materials. Here, we systematically demonstrate the growth of vanadium-doped molybdenum disulfide (V-doped MoS2) monolayers via an alkali metal-assisted chemical vapor deposition method. Scanning transmission electron microscopy demonstrated that V atoms substituted the Mo atoms and became uniformly distributed in the MoS2 monolayers. This was also confirmed by Raman and X-ray photoelectron spectroscopy. Power-dependent photoluminescence spectra clearly revealed the enhanced B-exciton emission characteristics in the V-doped MoS2 monolayers (with low doping concentration). Most importantly, through temperature-dependent study, we observed efficient valley scattering of the B-exciton, greatly enhancing its emission intensity. Carrier transport experiments indicated that typical p-type conduction gradually arisen and was enhanced with increasing V composition in the V-doped MoS2, where a clear n-type behavior transited first to ambipolar and then to lightly p-type charge carrier transport. In addition, visible to infrared wide-band photodetectors based on V-doped MoS2 monolayers (with low doping concentration) were demonstrated. The V-doped MoS2 monolayers with distinct B-exciton emission, enhanced p-type conduction and broad spectral response can provide new platforms for probing new physics and offer novel materials for optoelectronic applications.

9.
Artículo en Inglés | MEDLINE | ID: mdl-37885218

RESUMEN

A brain-like neuromorphic computing system, as compared with traditional Von Neumann architecture, has broad application prospects in the fields of emerging artificial intelligence (AI) due to its high fault tolerance, excellent plasticity, and parallel computing capability. A neuromorphic visuosensory and memory system, an important branch of neuromorphic computing, is the basis for AI to perceive, process, and memorize optical information, now still suffering from nonlinearity of synaptic weight, crosstalk issues, and integration incompatibility, hindering the high-level training and inference accuracy. In this work, we propose a new optoelectronic neuromorphic architecture by integrating an electrochromic device and a perovskite photodetector. Ascribing to the superior memory characteristics of the electrochromic device and sensitive light response of the perovskite photodetector, the neuromorphic device shows typical visual synaptic functionalities such as light triggering, neural facilitation, long-term potentiation, and depression (LTP and LTD). Furthermore, by adjusting the intensity and wavelength of external light signals, the visual synaptic function of the device can be modulated, enabling the device to exhibit high weight linearity in all current output ranges and improve information processing capability and image recognition accuracy. Moreover, both the electrochromic and perovskite layers possess the advantage of large area fabrication and integration, which enables the fabrication of large device arrays with high integration compatibility and scalability. In this study, 10 × 10 device arrays are demonstrated and each device shows uniform light responses, memory behaviors, and synaptic performances. MNIST and CIFAR-10 algorithms are used to simulate the image recognition properties of the synaptic architecture, and the calculated recognition accuracy is 97.94 and 91.04%, respectively, with an error less than 2.5%. The proposed artificial visual neuromorphic architecture will provide a potential device prototype for efficient visual neuromorphic systems.

10.
ACS Omega ; 8(27): 24503-24512, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37457458

RESUMEN

Using pyrolants instead of warhead charges can release red light and thick smoke for target practice to highlight the safety of the impact point and dud disposal. In order to find the ideal material, the combustion and kinetic properties of two Zn-Mg alloys at critical proportions were investigated. Thermogravimetry/differential scanning calorimetry (TG/DSC) experiments in pure oxygen were conducted with atomized Zn-Mg alloy powder in the ratio of 7:3 and the ratio of 8:2 with three particle diameters under different heating rates. The kinetic parameters of the six materials were obtained by ASTM E698 and Ozawa-Flynn-Wall (OFW) methods, indicating that the activation energy (Eα) of the 7:3 Zn-Mg alloy powder was lower than that of the 8:2 Zn-Mg alloy powder when the particle size distributions are similar. By the method of nonlinear multivariate regression, the oxidation reaction of Zn-Mg alloy powder was divided into two steps. The proportion of mass gain of the first-step reaction of 7:3 Zn-Mg alloy powder was 0.462-0.518, and the proportion of mass gain of the first-step reaction of 8:2 Zn-Mg alloy powder was 0.138-0.228. Reaction mechanism functions of the two-step reaction of Zn-Mg alloy oxidation were derived as f(α) = (1 - α)n(1 + kcat·α). The results of combustion experiments showed that the pyrolants composed of 7:3 alloy can burn stably to produce satisfactory smoke and light signals, while the pyrolants composed of 8:2 alloy cannot achieve this. The 7:3 Zn-Mg alloy powder is an ideal ingredient for pyrotechnic compositions.

11.
ACS Appl Mater Interfaces ; 15(19): 23573-23582, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37141554

RESUMEN

Artificial synapse networks capable of massively parallel computing and mimicking biological neural networks can potentially improve the processing efficiency of existing information technologies. Semiconductor devices functioning as excitatory and inhibitory synapses are crucial for developing intelligence systems, such as traffic control systems. However, achieving reconfigurability between two working modes (inhibitory and excitatory) and bilingual synaptic behavior in a single transistor remains challenging. This study successfully mimics a bilingual synaptic response using an artificial synapse based on an ambipolar floating gate memory comprising tungsten selenide (WSe2)/hexagonal boron nitride (h-BN)/ molybdenum telluride (MoTe2). In this WSe2/h-BN/MoTe2 structure, ambipolar semiconductors WSe2 and MoTe2 are inserted as channel and floating gates, respectively, and h-BN serves as the tunneling barrier layer. Using either positive or negative pulse amplitude modulations at the control gate, this device with bipolar channel conduction produced eight distinct resistance states. Based on this, we experimentally projected that we could achieve 490 memory states (210 hole-resistance states + 280 electron-resistance states). Using the bipolar charge transport and multistorage states of WSe2/h-BN/MoTe2 floating gate memory, we mimicked reconfigurable excitatory and inhibitory synaptic plasticity in a single device. Furthermore, the convolution neural network formed by these synaptic devices can recognize handwritten digits with an accuracy of >92%. This study identifies the unique properties of heterostructure devices based on two-dimensional materials as well as predicts their applicability in advanced recognition of neuromorphic computing.

12.
Adv Sci (Weinh) ; 10(16): e2300120, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37058134

RESUMEN

Optoelectronic synaptic devices integrating light-perception and signal-storage functions hold great potential in neuromorphic computing for visual information processing, as well as complex brain-like learning, memorizing, and reasoning. Herein, the successful growth of MoS2 monolayer arrays assisted by gold nanorods guided precursor nucleation is demonstrated. Optical, spectral, and morphology characterizations of MoS2 prove that arrayed flakes are homogeneous monolayers, and they are further fabricated as optoelectronic devices showing featured photocurrent loops and stable optical responses. Typical synaptic behaviors of photo-induced short-term potentiation, long-term potentiation, and paired pulse facilitation are recorded under different light stimulations of 450, 532, and 633 nm lasers at various excitation powers. A visual sensing system consisting of 5 × 6 pixels is constructed to simulate the light-sensing image mapped by forgetting curves in real time. Moreover, the system presents the ability of utilizing associated images to restore vague and incomplete memories, which successfully mimics human intelligent behaviors of association memory and logical reasoning. The work emulates the brain-like artificial intelligence using arrayed 2D semiconductors, which paves an avenue to achieve smart retina and complex brain-like system.


Asunto(s)
Inteligencia Artificial , Redes Neurales de la Computación , Humanos , Molibdeno , Sinapsis/fisiología , Percepción Visual
13.
ACS Omega ; 8(8): 7950-7955, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36873036

RESUMEN

The muzzle of barrel weapons produces a large amount of smoke (muzzle smoke), a major source of pollution in the battlefield. Quantitative assessment of muzzle smoke is an important support for the development of advanced propellants. However, due to the lack of effective measurement methods for field experiments, most of the previous studies were based on a smoke box, and few studies have focused on muzzle smoke in the field environment. In view of the nature of the muzzle smoke and the conditions of the field environment, the characteristic quantity of muzzle smoke (CQMS) was defined based on the Beer-Lambert law in this paper. CQMS is used to characterize the danger level of muzzle smoke produced by the propellant charge, and theoretical calculations indicated that when the transmittance is e -2, the impact of the measurement errors on CQMS can be minimized. Seven firings with the same propellant charge of a 30 mm gun were carried out in a field environment to verify the effectivity of CQMS. The measurement uncertainty analysis on the experimental results showed that the CQMS of the propellant charge used in this study was 2.35 ± 0.06 m2, which indicates that CQMS can be used to quantitatively assess muzzle smoke.

14.
Proc Natl Acad Sci U S A ; 120(5): e2214655120, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36689658

RESUMEN

In parallel with pronounced cooling in the oceans, vast areas of the continents experienced enhanced aridification and restructuring of vegetation and animal communities during the Late Miocene. Debate continues over whether pCO2-induced global cooling was the primary driver of this climate and ecosystem upheaval on land. Here we present an 8 to 5 Ma land surface temperatures (LST) record from East Asia derived from paleosol carbonate clumped isotopes and integrated with climate model simulations. The LST cooled by ~7 °C between 7.5 and 5.7 Ma, followed by rapid warming across the Miocene-Pliocene transition (5.5 to 5 Ma). These changes occurred synchronously with variations in alkenone and Mg/Ca-based sea surface temperatures and with hydroclimate and ecosystem shifts in East Asia, highlighting a global climate forcing mechanism. Our modeling experiments additionally demonstrate that pCO2-forced cooling would have altered moisture transfer and pathways and driven extensive aridification in East Asia. We, thus, conclude that the East Asian hydroclimate and ecosystem shift was primarily controlled by pCO2-forced global cooling between 8 and 5 Ma.


Asunto(s)
Dióxido de Carbono , Ecosistema , Animales , Clima , Asia Oriental , Temperatura
15.
Sci Rep ; 13(1): 1480, 2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36707528

RESUMEN

It is quite a challenge to obtain the temperature and species concentration fields of muzzle flash at high noise level. In this numerical study, radiation intensity of muzzle flash received by the high-speed Complementary Metal-Oxide-Semiconductor (CMOS) camera was simulated based on the line-of-sight method in the direct radiative transfer problem. The inverse radiative transfer problem of reconstructing distributions of temperature and soot volume fraction from the knowledge of flame radiation intensity was transformed into a minimization optimization problem and a meta-heuristic algorithm was used to solve the problem. The effects of the number of detection lines, optical thickness and measurement errors on the reconstruction results were discussed in details. A method to estimate the noise level of radiation intensity was developed, experimental results showed that the signal-to-noise ratio (SNR) of radiation intensity can be successfully inferred when the SNR is greater than 20 dB. Subsequently, prior knowledge of the noise level was introduced in the regularization to achieve a meaningful approximation of the exact value. The reconstruction of the soot volume fraction filed with SNR greater than 40 dB is considered successful with the inclusion of an appropriate regularization term in the objective function, and the reconstruction of the temperature field is feasible even with SNR as low as 15 dB. The high tolerance to the noise level of the radiation intensity gives the reconstruction algorithm the potential to be used in practical experiments of muzzle flash.

16.
Light Sci Appl ; 11(1): 337, 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36443284

RESUMEN

Brain-inspired neuromorphic computing, featured by parallel computing, is considered as one of the most energy-efficient and time-saving architectures for massive data computing. However, photonic synapse, one of the key components, is still suffering high power consumption, potentially limiting its applications in artificial neural system. In this study, we present a BP/CdS heterostructure-based artificial photonic synapse with ultra-low power consumption. The device shows remarkable negative light response with maximum responsivity up to 4.1 × 108 A W-1 at VD = 0.5 V and light power intensity of 0.16 µW cm-2 (1.78 × 108 A W-1 on average), which further enables artificial synaptic applications with average power consumption as low as 4.78 fJ for each training process, representing the lowest among the reported results. Finally, a fully-connected optoelectronic neural network (FONN) is simulated with maximum image recognition accuracy up to 94.1%. This study provides new concept towards the designing of energy-efficient artificial photonic synapse and shows great potential in high-performance neuromorphic vision systems.

17.
Sci Data ; 9(1): 371, 2022 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-35764652

RESUMEN

The Phanerozoic Eon has witnessed considerable changes in the climate system as well as abundant animals and plant life. Therefore, the evolution of the climate system in this Eon is worthy of extensive research. Only by studying climate changes in the past can we understand the driving mechanisms for climate changes in the future and make reliable climate projections. Apart from observational paleoclimate proxy datasets, climate simulations provide an alternative approach to investigate past climate conditions of the Earth, especially for long time span in the deep past. Here we perform 55 snapshot simulations for the past 540 million years, with a 10-million-year interval, using the Community Earth System Model version 1.2.2 (CESM1.2.2). The climate simulation dataset includes global distributions of monthly surface temperatures and precipitation, with a 1° horizontal resolution of 0.9° × 1.25° in latitude and longitude. This open access climate dataset is useful for multidisciplinary research, such as paleoclimate, geology, geochemistry, and paleontology.

18.
Psychiatr Danub ; 34(2): 288-295, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35772139

RESUMEN

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) mainly manifests as learning difficulties, emotional impulsiveness, excessive activities, and attention deficit disorder. Given that it can influence social communication abilities, as well as physical and psychological health and viability, ADHD rehabilitation has attracted close attention. This study aims to discuss the influences of musicotherapy combined with cognitive behavioral intervention on the cognitive ability of children with ADHD and provide some references for ADHD rehabilitation. SUBJECTS AND METHODS: A total of 120 children with ADHD in the Cooperative Hospital of Guangzhou University from June 2018 to May 2021 were chosen as the research objects. They were divided randomly into the control and observation groups with 60 cases in each group via the observing random digital method. The control group was the blank control and did not receive any intervention. The observation group received 16 weeks of musicotherapy combined with cognitive behavioral intervention. Symptoms and the results of the numerical cross-attention test, the Wisconsin card sorting test, the combined Raven's test (CRT), the Wechsler intelligence scale for children test, and Conner's child behavioral scale for parents of the two groups before and after the intervention were compared. RESULTS: The relevant indexes of the control group did not show any significant changes after the intervention (P>0.05). In the intervention group, the accurately crossed number and net scores increased significantly, whereas the wrongly crossed number and missed crossed number scores and error; attention deficit; hyperactivity-impulsiveness; and ADHD-RS-Ⅳ total scores declined dramatically after intervention relative to those before the intervention. Moreover, the above indexes of the observation group showed more significant improvements than those of the control group (P<0.05). In the observation group, the conceptual level percentage and the number of completed classes had significantly increased and the number of discontinuous errors and number of continuous errors after the intervention had dropped sharply compared with those before. The above indexes of the observation group had improved significantly compared with those of the control group (P<0.05). Moreover, in both groups, the concentration/attention factor and CRT scores increased dramatically and the scores of Conner's child behavior scale after the intervention had dropped significantly compared with those before. After intervention, the above indexes of the observation group showed greater improvements than those of the control group (P<0.05). CONCLUSIONS: The musicotherapy combined with cognitive behavioral intervention can improve the cognitive functions of children with ADHD and has clinical application values.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Terapia Cognitivo-Conductual , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Niño , Cognición , Humanos , Habilidades Sociales , Escalas de Wechsler
19.
ACS Omega ; 7(15): 12617-12623, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35474839

RESUMEN

In this study, magnesium aluminate spinel (MgAl2O4) was synthesized by a self-propagating high-temperature synthesis method using Mg-Al alloy with a Mg/Al mass ratio of 50:50 as raw material. Synthesized MgAl2O4 was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, UV-vis diffused reflectance spectroscopy, photoluminescence, and thermogravimetric differential scanning calorimetry techniques. The results show that synthesized products are of high purity and excellent crystallinity. However, the particle size is not uniform and there is obvious agglomeration. The crystallite size of spinel phase is calculated to be 37.78 nm. In the UV band, the synthesized MgAl2O4 has a certain absorption capacity, and the extrapolated band gap is 4.02 eV. The synthesis mechanism was studied, and continued rupture and growth of the oxidation layer is thought to be responsible for grain refinement.

20.
ACS Omega ; 7(12): 10469-10475, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35382280

RESUMEN

The energetic performance of hexanitrohexaazaisowurtzitane (CL-20) was modulated with two energetic coordination polymers (ECPs), [Cu(ANQ)2(NO3)2] and [Ni(CHZ)3](ClO4)2, in this study by a two-step method. First, tannic acid polymerized in situ on the surface of CL-20 crystals. Then, [Cu(ANQ)2(NO3)2] and [Ni(CHZ)3](ClO4)2 were hydrothermally formed on the surface of CL-20/TA, respectively. Explosion performance tests show that the impact sensitivity of the coated structure CL-20/TA/[Cu(ANQ)2(NO3)2] is 58% less than that of CL-20 with no energy decrease. On the other hand, CL-20/TA/[Ni(CHZ)3](ClO4)2 can be initiated by a low laser energy of 107.3 mJ (Nd:YAG, 1064 nm, 6.5 ns pulse width), whereas CL-20 cannot be initiated by even 4000 mJ laser energy. This study shows that it is feasible to modify the performance of CL-20 by introducing energetic CPs with certain properties, like high energy insensitive, laser-sensitive, etc., which could be a prospective method for designing high energy insensitive energetic materials in the future.

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