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1.
Angew Chem Int Ed Engl ; : e202406552, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38766881

RESUMO

Triply interlocked [2]catenane complexes featuring two identical, mechanically interlocked units are extraordinarily rare chemical compounds, whose properties and applications remain open to detailed studies. Herein, we introduce the rational design of a new ligand precursor, L1, suitable for the synthesis of six triply interlocked [2]catenanes by coordination-driven self-assembly. The interlocked compounds can be reversibly converted into the corresponding simple triangular prism metallacage by addition of H2O or DMF solvents to their CH3OH solutions, thereby demonstrating the importance of π⋅⋅⋅π stacking and hydrogen bonding interactions in the formation of triply interlocked [2]catenanes. Moreover, extensive studies have been conducted to assess the remarkable photothermal conversion performance. Complex 6 a, exhibiting outstanding photothermal conversion performance (conversion efficiency in solution : 31.82 %), is used to prepare novel photoresponsive elastomer in combination with thermally activated liquid crystal elastomer. The resultant material displays robust response to near-infrared (NIR) laser and the capability of completely reforming the shape and reversible actuation, paving the way for the application of half-sandwich organometallic units in photo-responsive smart materials.

2.
Bioengineering (Basel) ; 11(5)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38790297

RESUMO

Dysphagia is a pervasive health issue that impacts diverse demographic groups worldwide, particularly the elderly, stroke survivors, and those suffering from neurological disorders. This condition poses substantial health risks, including malnutrition, respiratory complications, and increased mortality. Additionally, it exacerbates economic burdens by extending hospital stays and escalating healthcare costs. Given that this disorder is frequently underestimated in vulnerable populations, there is an urgent need for enhanced diagnostic and therapeutic strategies. Traditional diagnostic tools such as the videofluoroscopic swallowing study (VFSS) and flexible endoscopic evaluation of swallowing (FEES) require interpretation by clinical experts and may lead to complications. In contrast, non-invasive sensors offer a more comfortable and convenient approach for assessing swallowing function. This review systematically examines recent advancements in non-invasive swallowing function detection devices, focusing on the validation of the device designs and their implementation in clinical practice. Moreover, this review discusses the swallowing process and the associated biomechanics, providing a theoretical foundation for the technologies discussed. It is hoped that this comprehensive overview will facilitate a paradigm shift in swallowing assessments, steering the development of technologies towards more accessible and accurate diagnostic tools, thereby improving patient care and treatment outcomes.

3.
Mater Horiz ; 11(10): 2483-2493, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38477135

RESUMO

Liquid crystal elastomers (LCEs) blended with photothermal nanofillers can reversibly and rapidly deform their shapes under external optical stimuli. However, nanointerfacial slipping inevitably occurs between the LCE molecules and the nanofillers due to their weak physical interactions, eventually resulting in cyclic instability. This work presents a versatile strategy to fabricate nanointerfacial-slipping-restricted photoactuation elastomers by chemically bonding the nanofillers into a thermally actuatable liquid crystal network. We experimentally and theoretically investigated three types of metal-based nanofillers, including zero-dimensional (0D) nanoparticles, one-dimensional (1D) nanowires, and two-dimensional (2D) nanosheets. The toughly crosslinked nanointerface allows for remarkably promoted interfacial thermal conductivity and stress transfer. Therefore, the resultant actuators enable the realization of long-term-cyclic-stability 4D-printed flexible intelligent systems such as the optical gripper, crawling robot, light-powered self-sustained windmill, butterflies with fluttering wings, and intelligent solar energy collection system.

4.
Biomimetics (Basel) ; 9(3)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38534855

RESUMO

Malignant tumors have become one of the serious public health problems in human safety and health, among which the chest and abdomen diseases account for the largest proportion. Early diagnosis and treatment can effectively improve the survival rate of patients. However, respiratory motion in the chest and abdomen can lead to uncertainty in the shape, volume, and location of the tumor, making treatment of the chest and abdomen difficult. Therefore, compensation for respiratory motion is very important in clinical treatment. The purpose of this review was to discuss the research and development of respiratory movement monitoring and prediction in thoracic and abdominal surgery, as well as introduce the current research status. The integration of modern respiratory motion compensation technology with advanced sensor detection technology, medical-image-guided therapy, and artificial intelligence technology is discussed and analyzed. The future research direction of intraoperative thoracic and abdominal respiratory motion compensation should be non-invasive, non-contact, use a low dose, and involve intelligent development. The complexity of the surgical environment, the constraints on the accuracy of existing image guidance devices, and the latency of data transmission are all present technical challenges.

5.
Adv Sci (Weinh) ; 11(2): e2307862, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37985651

RESUMO

More recently, soft actuators have evoked great interest in the next generation of soft robots. Despite significant progress, the majority of current soft actuators suffer from the lack of real-time sensory feedback and self-control functions, prohibiting their effective sensing and multitasking functions. Therefore, in this work, a near-infrared-driven bimorph membrane, with self-sensing and feedback loop control functions, is produced by layer by layer (LBL) assembling MXene/PDDA (PM) onto liquid crystal elastomer (LCE) film. The versatile integration strategy successfully prevents the separation issues that arise from moduli mismatch between the sensing and the actuating layers, ultimately resulting in a stable and tightly bonded interface adhesion. As a result, the resultant membrane exhibited excellent mechanical toughness (tensile strengths equal to 16.3 MPa (||)), strong actuation properties (actuation stress equal to 1.56 MPa), and stable self-sensing (gauge factor equal to 4.72) capabilities. When applying the near-infrared (NIR) laser control, the system can perform grasping, traction, and crawling movements. Furthermore, the wing actuation and the closed-loop controlled motion are demonstrated in combination with the insect microcontroller unit (MCU) models. The remote precision control and the self-sensing capabilities of the soft actuator pave a way for complex and precise task modulation in the future.

7.
Front Plant Sci ; 13: 1009452, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330240

RESUMO

The site of Qujialing experienced a long, sustained process of the development of Neolithic culture in the Jianghan Plain, with a period of some1600 years. Our previous studies based on macrofossil remains and phytoliths revealed that rice (Oryza sativa) from Qujialing was already domesticated, and millet (Setaria italica and Panicum miliaceum) had also been spread into the site since the Youziling Culture period (5800-5100 BP). Nevertheless, no direct evidence has been provided regarding the daily consumed plant foods, especially plant foods obtained by gathering, throughout the site occupation. This paper thus examines pottery sherds (n=41) associated with culinary practices from Qujialing with starch grain analysis. Apart from starch grains from rice and millet, the results indicate that job's tears (Coix lacryma-jobi), lotus roots (Nelumbo nucifera), tubers possibly from Chinese yam (Dioscorea panthainca), acorns (Quercus sp.), and beans (Vigna sp. or/and Vicia sp.) were consumed by the ancient Qujialing people, within job's tears and lotus roots were not discovered before in the macrofossil remains and phytoliths. Combining the starch data and multiple lines of evidence from macrofossil remains and phytoliths, it is suggested that rice was among the most frequently consumed plant foods since the first occupation phase at Qujialing, while acorns could have been gradually replaced by other agricultural products (i.e., rice) and became less important food ingredients, especially when agriculture was more developed in the last occupation phase at Qujialing. These novel findings not only complement our previous research by providing the first line of evidence of paleodiet in the Jianghan Plain from the perspective of starch grain analysis but also delivers a better understanding of the characterized dietary trends and agricultural development in the research region.

8.
Genes (Basel) ; 13(11)2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36360314

RESUMO

The site of Zhengzhou Shang City (ca. 1509-1315 cal. BC) was the capital of the early Shang Dynasty in China. Archaeological excavations have unearthed a ditch containing approximately one hundred unusual dead human skulls in the rammed-earth foundations of the palace area. The identity and origin of the skulls have long been disputed. In this work, strontium, carbon and nitrogen stable isotope analyses were carried out on 11 human skulls and 1 tooth from the ditch, as well as on 11 human bones, 11 human teeth from the ordinary tombs and 10 pig teeth from the Zhengzhou Shang City site. We determined that, in Zhengzhou Shang City, the local strontium isotope ratio ranges from 0.711606 to 0.711884, and ordinary inhabitants consumed mainly C4 plants supplemented by C3 plants. Moreover, humans buried in the ditch have 87Sr/86Sr values from 0.711335 to 0.711741 and consumed only C4 plants. Combining the isotopic data with the archaeological and cultural context, it is concluded that the unusual human skulls in the ditch are most likely those of prisoners of war captured by the central forces conquering the Xiaomintun area of Anyang in the early Shang Dynasty. The results provide valuable insight into the history of violence and military warfare in the early Chinese dynasty.


Assuntos
Militares , Dente , Humanos , Suínos , Animais , Isótopos , Arqueologia , Crânio
10.
Mater Horiz ; 9(3): 1045-1056, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35040453

RESUMO

Photoresponsive soft actuators with the unique merits of flexibility, contactless operation, and remote control have huge potential in technological applications of bionic robotics and biomedical devices. Herein, a facile strategy was proposed to prepare an intrinsically-photoresponsive elastomer by chemically grafting carbon nanotubes (CNTs) into a thermally-sensitive liquid-crystalline elastomer (LCE) network. Highly effective dispersion and nematic orientation of CNTs in the intrinsic LCE matrix were observed to yield anchoring energies ranging from 1.65 × 10-5 J m-2 to 5.49 × 10-7 J m-2, which significantly enhanced the mechanical and photothermal properties of the photoresponsive elastomer. When embedding an ultralow loading of CNTs (0.1 wt%), the tensile strength of the LCE increased by 420% to 13.89 MPa (||) and 530% to 3.94 MPa (⊥) and exhibited a stable response to repeated alternating cooling and heating cycles, as well as repeated UV and infrared irradiation. Furthermore, the shape transformation, locomotion, and photo-actuation capabilities allow the CNT/LCE actuator to be applied in high-definition biomechanical applications, such as phototactic flowers, serpentine robots and artificial muscles. This design strategy may provide a promising method to manufacture high-precision, remote-control smart devices.


Assuntos
Cristais Líquidos , Nanotubos de Carbono , Robótica , Fenômenos Biomecânicos , Elastômeros/química , Cristais Líquidos/química
11.
Polymers (Basel) ; 13(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204168

RESUMO

Liquid crystalline elastomers (LCEs) are lightly crosslinked polymers that combine liquid crystalline order and rubber elasticity. Owing to their unique anisotropic behavior and reversible shape responses to external stimulation (temperature, light, etc.), LCEs have emerged as preferred candidates for actuators, artificial muscles, sensors, smart robots, or other intelligent devices. Herein, we discuss the basic action, control mechanisms, phase transitions, and the structure-property correlation of LCEs; this review provides a comprehensive overview of LCEs for applications in actuators and other smart devices. Furthermore, the synthesis and processing of liquid crystal elastomer are briefly discussed, and the current challenges and future opportunities are prospected. With all recent progress pertaining to material design, sophisticated manipulation, and advanced applications presented, a vision for the application of LCEs in the next generation smart robots or automatic action systems is outlined.

12.
Nat Ecol Evol ; 3(10): 1415-1418, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31527727

RESUMO

Despite the growing importance of farmed fish for contemporary economies, the origins of aquaculture are poorly known. Although it is widely assumed that fish domestication began much later than the domestication of land animals, the evidence is largely negative. Here, we use age-mortality and species-selection profiles of fish bones from prehistoric East Asia to show that managed aquaculture of common carp (Cyprinus carpio) was present at the Early Neolithic Jiahu site, Henan Province, China, by around 6000 BC.


Assuntos
Carpas , Animais , Aquicultura , China , Ásia Oriental , Alimentos Marinhos
13.
Nat Ecol Evol ; 3(10): 1494, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31551524

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

14.
PLoS One ; 11(12): e0168042, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27941996

RESUMO

Pottery, bone implements, and stone tools are routinely found at Neolithic sites. However, the integrity of textiles or silk is susceptible to degradation, and it is therefore very difficult for such materials to be preserved for 8,000 years. Although previous studies have provided important evidence of the emergence of weaving skills and tools, such as figuline spinning wheels and osseous lamellas with traces of filament winding, there is a lack of direct evidence proving the existence of silk. In this paper, we explored evidence of prehistoric silk fibroin through the analysis of soil samples collected from three tombs at the Neolithic site of Jiahu. Mass spectrometry was employed and integrated with proteomics to characterize the key peptides of silk fibroin. The direct biomolecular evidence reported here showed the existence of prehistoric silk fibroin, which was found in 8,500-year-old tombs. Rough weaving tools and bone needles were also excavated, indicating the possibility that the Jiahu residents may possess the basic weaving and sewing skills in making textile. This finding may advance the study of the history of silk, and the civilization of the Neolithic Age.


Assuntos
Seda/história , China , Fibroínas/análise , História Antiga , Humanos , Espectrometria de Massas , Solo/química , Têxteis/história
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(11): 3140-4, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22242535

RESUMO

The major elements in the early neolithic potteries unearthed from Xiaohuangshan site, Zhejiang Province and Jiahu site, Henan Province were determined by energy disperse X-ray fluorescence (EDXRF). The results show that the chemical compositions of the potteries from these two sites possess obvious regional features respectively. Compared with the specimen from Jiahu site, the potteries from Xiaohuangshan site have the common feature of ancient Chinese southern ceramics with high silicon and low aluminum contents. Simultaneously, the chemical composition of Xiaohuangshan pottery samples nearly unchanged from its early stage to the last stage. This phenomenon indicates that the source of the ceramic raw materials of Xiaohuangshan site was stable, and the continuous improvement of its pottery quality was mainly due to the progress in sintering techniques. However, the chemical composition of Jiahu potteries changed a lot in its three different periods. This change occurred because a large number of admixtures were added to the pottery bodies to improve their operating performances. These results also show that the improvements of pottery making techniques in different Chinese areas may have their own evolution directions respectively for the different geographical environments.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(8): 2295-8, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20939361

RESUMO

Fanchang kiln was the earliest Chinese bluish-white porcelain kiln which first fired this special porcelain class as early as in Five Dynasties (AD 907-960). However, this important kiln declined rapidly in the middle North Song dynasty (AD 1023-1085). As to the decline reason, it is still not clearly identified till now. In order to find the truth, wavelength-dispersive X-ray fluorescence (WDXRF) was used to determine the elemental abundance patterns of its porcelain bodies in Five Dynasties, the early North Song dynasty and the middle North Song dynasty. The analytical results indicate that the chemical compositions of major, minor and trace elements in porcelain bodies changed greatly in the middle North Song dynasty. Combined with the results of INAA and glaze study, this change in elemental composition should be caused by the change in porcelain raw materials or body-making crafts. Meanwhile, it was just this change that led to the quality decline of raw material and rapid collapse of Fan-chang kiln in the middle North Song dynasty shortly after its establishment.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(4): 1130-3, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20545178

RESUMO

Based on the analysis of Raman spectroscopy and XRD methods, the structures of different pigments on the painted pottery from the Monarch Bai Tomb of Zhongli State in the middle and late Spring and Autumn period at Shungdun Village, Bengbu City, Anhui Province were analyzed. The result shows that all the pigments, including red, yellow and black pigments, have been well preserved, and these three pigments were identified as cinnabar, goethite and carbon black respectively. Both Raman spectroscopy and XRD analysis show that the crystal composition of red pigments, cinnabar, is very pure without quartz crystal, the associated crystal of natural cinnabar, and at the same time the crystal size of cinnabar is possibly at the nanometer scale. It suggests that this red pigments perhaps were a synthetic material or processed and purified by our ancestors. The discovery of goethite shows that this mineral has been used as pigments as early as in the Spring and Autumn period. This is the earliest example that goethite was used as yellow pigments.

18.
Proc Natl Acad Sci U S A ; 101(51): 17593-8, 2004 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-15590771

RESUMO

Chemical analyses of ancient organics absorbed into pottery jars from the early Neolithic village of Jiahu in Henan province in China have revealed that a mixed fermented beverage of rice, honey, and fruit (hawthorn fruit and/or grape) was being produced as early as the seventh millennium before Christ (B.C.). This prehistoric drink paved the way for unique cereal beverages of the proto-historic second millennium B.C., remarkably preserved as liquids inside sealed bronze vessels of the Shang and Western Zhou Dynasties. These findings provide direct evidence for fermented beverages in ancient Chinese culture, which were of considerable social, religious, and medical significance, and help elucidate their earliest descriptions in the Shang Dynasty oracle inscriptions.


Assuntos
Bebidas/análise , Bebidas/história , Arqueologia , China , Fermentação , Frutas/história , História Antiga , Mel/história , Oryza/história , Espectroscopia de Infravermelho com Transformada de Fourier , Vinho/análise , Vinho/história
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