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1.
Zhongguo Zhen Jiu ; 43(11): 1333-1337, 2023 Sep 08.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37986259

RESUMO

A moxibustion device with the functions of auricular fumigation moxibustion and heat-sensitive moxibustion is designed. The smoke of the ignited moxa stick is used for the fumigation moxibustion at the external auditory canal, while the heat generated works on Dazhui (GV 14) for heat-sensitive moxibustion. The device consists of five parts, i.e. combustion chamber, smoke pipe, smoke processing chamber, power module and connector. It solves the limitations such as unpleasant experience in treatment, unfavorable temperature control, easy scalding and excessive manual dependence induced by usual fumigation moxibustion and during heat-sensitive moxibustion. This moxibustion device may improve the safety and convenience when delivering the treatment with fumigation moxibustion and heat-sensitive moxibustion, as well as the work efficiency of medical staff.


Assuntos
Moxibustão , Humanos , Temperatura Alta , Fumigação , Fumaça , Temperatura
2.
Curr Med Sci ; 43(5): 908-918, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37700190

RESUMO

OBJECTIVE: Body fluid mixtures are complex biological samples that frequently occur in crime scenes, and can provide important clues for criminal case analysis. DNA methylation assay has been applied in the identification of human body fluids, and has exhibited excellent performance in predicting single-source body fluids. The present study aims to develop a methylation SNaPshot multiplex system for body fluid identification, and accurately predict the mixture samples. In addition, the value of DNA methylation in the prediction of body fluid mixtures was further explored. METHODS: In the present study, 420 samples of body fluid mixtures and 250 samples of single body fluids were tested using an optimized multiplex methylation system. Each kind of body fluid sample presented the specific methylation profiles of the 10 markers. RESULTS: Significant differences in methylation levels were observed between the mixtures and single body fluids. For all kinds of mixtures, the Spearman's correlation analysis revealed a significantly strong correlation between the methylation levels and component proportions (1:20, 1:10, 1:5, 1:1, 5:1, 10:1 and 20:1). Two random forest classification models were trained for the prediction of mixture types and the prediction of the mixture proportion of 2 components, based on the methylation levels of 10 markers. For the mixture prediction, Model-1 presented outstanding prediction accuracy, which reached up to 99.3% in 427 training samples, and had a remarkable accuracy of 100% in 243 independent test samples. For the mixture proportion prediction, Model-2 demonstrated an excellent accuracy of 98.8% in 252 training samples, and 98.2% in 168 independent test samples. The total prediction accuracy reached 99.3% for body fluid mixtures and 98.6% for the mixture proportions. CONCLUSION: These results indicate the excellent capability and powerful value of the multiplex methylation system in the identification of forensic body fluid mixtures.

3.
Zhongguo Zhen Jiu ; 43(5): 597-9, 2023 May 12.
Artigo em Chinês | MEDLINE | ID: mdl-37161815

RESUMO

An automatic ash-removal heat-sensitive moxibustion device was developed, which could keep relatively constant temperature of heat-sensitive moxibustion, and realize the automatic ignition and automatic ash removal of moxa sticks during heat-sensitive moxibustion. The automatic ash-removal heat-sensitive moxibustion device comprises a bracket and a moxibustion box fixed on the top of the bracket; the bracket is composed of a base and a movable telescopic arm. This device can solve the problems of temperature instability, moxa ash blocking heat transfer and moxa ash falling during heat-sensitive moxibustion, avoiding the scalding caused by moxa ash falling, and reduce the workload of medical staff.


Assuntos
Temperatura Alta , Moxibustão , Humanos , Temperatura
4.
ACS Appl Mater Interfaces ; 14(45): 51244-51252, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36397310

RESUMO

Thermal-responsive hydrogel actuators have aroused a wide scope of research interest and have been extensively studied. However, their actuating behaviors are usually monotonous due to their unchangeable shapes and structures. Here, we report thermal-responsive poly(isopropylacrylamide-co-2-(dimethylamino)ethyl methacrylate)/alginate hydrogels with programmable external shapes and internal actuating trajectories. The volume phase transition temperatures of the resulting hydrogels can be tuned in a wide temperature range from 32 to above 50 °C by adjusting the monomer composition. While the formation and photo-dissociation of Fe3+-carboxylate tri-coordinates within the entire hydrogel network enable photo-responsive shape memory property, the insufficient dissociation of the tri-coordinates along the irradiation path gives rise to gradient crosslinking for realizing thermal-responsive actuation. Controlling the evolution of the gradient structure facilitates the regulation of the actuating amplitude. Furthermore, we show that the combination of these two types of shape-changing functionalities leads to more flexible and intricate shape-changing behaviors. One interesting application, a programmable hook with changeable actuating behaviors for lifting different objects with specific shapes, is also demonstrated. The proposed strategy can be extended to other types of actuating hydrogels with more advanced actuating behaviors.

5.
Angew Chem Int Ed Engl ; 61(29): e202205633, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35502463

RESUMO

Here, we combined the merits of emergent excitation-dependent (ExD) emission and circularly polarized luminescence to develop an excitation-dependent circularly polarized luminescence (ExD CPL) material showing unique features. A series of acylhydrazones based on a chiral tartaric skeleton was designed and found to self-assemble into helical nanostructures through non-covalent bonds. The helical assemblies showed ExD CPL due to the cooperation of chirality transfer and excited state intramolecular proton transfer (ESIPT). Remarkably, not only the emission wavelength could be tuned by the excitation wavelength but the handedness of CPL could be modulated in an inverted or ON/OFF manner as well, thus leading to the first example of an ExD inverted or ON/OFF switchable CPL system. Time-dependent density functional theory (TD-DFT) calculations were carried out to explain the inversion of ExD CPL. This work provided a new insight into the unprecedented handedness controllable ExD CPL, which showcased a new paradigm of the advanced CPL materials.


Assuntos
Luminescência , Teoria da Densidade Funcional , Tartaratos
6.
Nanoscale ; 14(3): 1001-1007, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35024717

RESUMO

How dissymmetrical tails (i.e. tails of different lengths) in one lipid molecule exert an impact on the structure and properties of the resulting assembly is an intriguing issue in both biological and material senses. However, the underlying mechanism that engenders such phenomena is still obscure, which prompted us to unmask it by exploring the self-assembly behaviours of artificial building blocks comprising dissymmetrical tails. Here, a series of Fmoc-protected ornithine lipids with dissymmetrical alkyl tails was designed and the dissymmetry of the two tails was found to hierarchically tune the self-assembled nanostructures from nanotubes to bundles and nanotwists. With the Fmoc-headgroup employed as a chromophorous probe, it was revealed that the alkyl chain dissymmetry controlled the interacting modes of van der Waals interactions between alkyl tails, π-π stacking between Fmoc motifs and hydrogen bonding formed by the three amide bonds in lipid bilayers. The counterbalance between those noncovalent interactions was responsible for such remarkable tuning ability towards self-assembly and emissive behaviours of the lipids, including circularly polarized light emission. This work provides insight into dissymmetrical tails-regulated biological structures and functions of natural lipids, and also sets up a novel strategy of rationally modulating chiral and emissive properties of supramolecular materials, i.e., tunable CPL materials, by exploitation of the tail dissymmetry.


Assuntos
Nanoestruturas , Nanotubos , Ligação de Hidrogênio , Ornitina
7.
ACS Appl Mater Interfaces ; 14(1): 1765-1773, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34965725

RESUMO

As the medium for self-assembly processes, solvents strongly influence the supramolecular assemblies via specific solute-solvent interactions, which may result in effective modulation of properties, self-assembled nanostructures, and functions through varying the solvent. Here, two kinds of pyridine-cyanostilbene functionalized chiral amphiphiles (l/d-PyPhG and l-PyG) were designed, and their self-assembly behaviors in different solvents were investigated. It was found that both amphiphiles formed gels in dimethyl sulfoxide (DMSO) and self-assembled into right-handed nanotwists, while they formed suspensions in ethanol consisting of left-handed nanotubes. Although the molecular chirality in the compounds remained unchanged in the two solvents, the nanoassemblies showed opposite handedness at the nanoscale together with opposite circular dichroism (CD) and circularly polarized luminescence (CPL) signals. Furthermore, when the amphiphiles were co-assembled with an achiral dye, it was found that efficient energy transfer took place in the systems composed of nanotubes rather than those composed of nanotwists. Therefore, by assembling molecules with the same molecular chirality in different solvents, a selective formation of helical nanotubes or nanotwists and the regulation of handedness as well as energy transfer efficiency were achieved.

8.
J Hazard Mater ; 401: 123334, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-32629355

RESUMO

Direct catalytic decomposition is a promising technology to control the emission of nitrous oxide (N2O) during fossil fuel combustion and various chemical industries. In this study, a series of NiO catalysts modified with different metal oxides (MaNiOb) were prepared by the co-precipitation method and employed for the direct catalytic decomposition of N2O. Bismuth (Bi) species was confirmed to be the most optimal promoter and the Bi0.1NiO1.15 catalyst with a Bi/Ni molar ratio of 0.1 exhibited the best activity over the temperature range of 300-450 °C. The addition of Bi species also promoted the steam resistance capability of the NiO catalyst. Moreover, the physicochemical properties of pure and Bi-modified NiO catalysts were further determined by several characterization methods. The surface areas and capacity of oxygen adsorption/desorption over the catalyst were noticeably improved with the doping of Bi species. Besides, the presence of doped-Bi facilitated the creation of both Ni3+ and surface oxygen vacancies on NiO, which promoted the performance of N2O decomposition. Whereas, the excessive Bi species would accumulate to form large Bi2O3 grains, which diminished the surface areas and covered the active sites on the catalysts, leading to the rapid degradation of N2O catalytic decomposition.

9.
Chem Soc Rev ; 49(24): 9095-9120, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33118560

RESUMO

Chiroptical switches, whose chiral optical signals such as optical rotatory dispersion (ORD), circular dichroism (CD) and circularly polarized luminescence (CPL) are reversibly interchangeable between two states, offer many promising applications in the fields of chiral sensing, optical displays, information storage, asymmetric catalysis and so on. Through various non-covalent interactions, supramolecular chiroptical switches have been constructed by combining the chiral and responsive functional components. This review summarizes the recent progress in the construction of supramolecular chiroptical switchable systems that reversibly respond to various stimuli, such as light, electricity, magnetic fields, mechanical force, solvents, pH, temperature, and chemical additives. The switching of supramolecular chirality in the forms of on/off, amplification/weakening and chirality inversion is shown. Additionally, the design of chiroptical switchable systems for chiral logic gates, data communication, chiral separation and asymmetric catalysis has been demonstrated. Future challenges in developing supramolecular chiroptical switches are also discussed.

11.
Chemistry ; 23(15): 3735-3742, 2017 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-28054424

RESUMO

Complexation of racemic 2,6-helic[6]arene 1 and its hexamethyl-substituted derivative 2 with quaternary ammonium salts, N-heterocyclic salts, and tetracyanoquinodimethane have been described in detail. It was found that host 2 could form stable complexes with acetyl choline, thiaacetyl choline, N,N,N-trimethylbenzenammonium salt, pyridinium, and 4,4'-bipyridinium salts in solution and/or in the solid state. The unsubstituted macrocycle 1 showed more significant complexation with the widely tested quaternary ammonium salts and N-heterocyclic salts, and exhibited stronger complexation towards the guests than its derivative 2. Moreover, it was found that macrocycle 1 and its derivative 2 could also complex with neutral electron-deficient tetracyanoquinodimethane (TCNQ), and the association constants were determined to be 2840±94 and 1358±46 m-1 , respectively. These results could make this new macrocycle and its derivatives find wide applications in the design and construction of functional supramolecular assemblies.

12.
Nurse Educ Today ; 49: 79-83, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27889582

RESUMO

BACKGROUND: Professional attitude is of great importance for nursing talents in the modern society. To develop an effective educational program for student nurses in China, an appropriate instrument is required for the assessment of their professional attitude. OBJECTIVE: To assess the validity and reliability of the Instrument of Professional Attitude for Student Nurses (IPASN) in Chinese version. METHODS: The original version of IPASN was translated through Brislin model (translation, back translation, culture adaption and pilot study) with the authorization from the developer. A total of 681 nursing students were chosen by stratified convenience sampling to assess construct validity using exploratory factor analysis (EFA). Besides, item analysis, Cronbach's alpha coefficients, test-retest reliability were conducted to test the psychometric properties in this part. A total of 204 nursing undergraduate trainees were selected by cluster convenience sampling to confirm the structure using confirmatory factor analysis (CFA) in another time. RESULTS: Corrected item-total correlations, alpha if item deleted were between 0.33 and 0.69, 0.906 and 0.913, respectively, indicating no item should be deleted. Cronbach alpha value was 0.91 for the total scale and Cronbach alpha coefficient for subscales ranged from 0.67 to 0.89. Test-retest reliability estimated from intraclass correlation coefficient (ICC) was 0.74 (P<0.05). Differences in item scores between the high-score group (the first 27%) and low-score group (the last 27%) were significant (P<0.001), indicating that the item discrimination ability was good. Seven subscales (contribution to increase of scientific information load, autonomy, community service, continuous education, to promote professional development, cooperation and theory guiding practice) were identified in EFA and confirmed in CFA, and explained 65.5% of the total variance. CONCLUSION: It indicated that the Chinese version of IPASN was valid and reliable for the evaluation of nursing students' professional attitude.


Assuntos
Profissionalismo/normas , Psicometria/normas , Reprodutibilidade dos Testes , Estudantes de Enfermagem/psicologia , Tradução , Atitude , China , Feminino , Humanos , Masculino , Psicometria/métodos , Adulto Jovem
13.
Org Biomol Chem ; 14(44): 10481-10488, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27761549

RESUMO

With an expanded electron-rich cavity and a fixed conformation, macrocycle H was found to encapsulate π-extended viologens G1-G4 to form the first case of pseudo[3]rotaxanes based on oxacalixarenes. The complexation was investigated in detail both in solution and in the solid state using NMR spectroscopy and X-ray crystallography. Due to the three-dimensional nonsymmetric structure of H, three orientational isomers of the pseudorotaxanes could be expected theoretically. However, as the crystal structure analysis revealed, only one of the three isomers was obtained with either G1 or G3. Moreover, with regard to the different lengths of the linkers in the guest molecules, completely opposite orientations of the macrocycles on the axles were observed, which could be explained by different complexation modes between the components in the pseudo[3]rotaxanes. Additionally, the complexation between the host and the guest could be reversibly switched on and off using a suitable acid and base. These results will provide us with the opportunity to design and elaborately regulate high-order molecular devices.

14.
Chem Asian J ; 11(19): 2756-2762, 2016 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-27167105

RESUMO

New triptycene-derived oxacalixarene H1 was efficiently synthesized by a template cyclization step, and anilino-substituted macrocycle H2 was subsequently afforded through straightforward nucleophilic displacement of the active chlorine atom in H1. Oxacalixarene H1 adopts a fixed boat-like 1,3-alternate conformation and shows moderate complexation abilities towards various bipyridinium salts. However, the affinities of H2 towards the guests were found to be substantially stronger, which could be tentatively attributed to the additional hydrogen-bonding site, π-π stacking site, and especially the increased electron richness of the host. Furthermore, the acid-base switchable complexation process between H1 and the bipyridinium salt was also realized, which could potentially facilitate the construction of high-level stimuli-responsive supramolecular structures based on the newly synthesized oxacalixarene.

15.
Angew Chem Int Ed Engl ; 55(17): 5304-8, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-27011062

RESUMO

A new class of chiral macrocyclic arene composed of three chiral 2,6-dihydroxyltriptycene subunits bridged by methylene groups was designed and synthesized. Structural studies showed that the macrocyclic molecule adopts a hex-nut-like structure with a helical chiral cavity and highly fixed conformation. Efficient resolution was achieved through the introduction of chiral auxiliaries to give a couple of enantiopure macrocycles, which exhibited high enantioselectivity towards three pairs of chiral compounds containing a trimethylamino group.

16.
Chem Sci ; 7(1): 469-474, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29899891

RESUMO

The manipulation of supramolecular devices to carry out sophisticated and programmed tasks is bound up with the spatial allocation of their components, especially the threading direction of the guest, which controls the host-guest orientation in the device. However, insights are needed to probe more possibilities for steering the threading direction. We have developed a new system consisting of a three-dimensional nonsymmetric oxacalixarene (H) with a fixed comformation and (bi)pyridinium salts (G1-G3), in which we found that based on the intrinsic discrepancies between the two semi-cavities of H, the electron densities of the axles greatly affect the threading direction. This was unequivocally demonstrated by NMR spectra and single crystal structures. With elaborate design, unidirectional threading was achieved, resulting in an oriented rotaxane. Therefore, we describe a new approach in which the threading direction and final orientation may be finely controlled by adjustment of the structure of the guest.

17.
J Recept Signal Transduct Res ; 34(5): 372-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24665917

RESUMO

Association between vitamin D receptor (VDR) BsmI (rs1544410) gene polymorphism and the risk of type 1 diabetes mellitus (T1DM) from the published reports are still conflicting. This study was conducted to evaluate the relationship between VDR BsmI gene polymorphism and the risk of T1DM using meta-analysis method. The association studies were identified from PubMed, and Cochrane Library on 1 December 2013, and eligible investigations were included and synthesized using meta-analysis method. Twenty-three reports were recruited into this meta-analysis for the association of VDR BsmI gene polymorphism with T1DM susceptibility. In overall populations, bb genotype was associated with T1DM, but the B allele and BB genotype were not. In Asians and Latino population, B allele and bb genotype were associated with TIDM risk, but BB genotype was not. In Caucasians, VDR BsmI gene polymorphism was not associated with the T1DM risk. In Africans, B allele and BB genotype were associated with T1DM risk, but the bb genotype was not. However, the sample size for Latino population and Africans was small. In conclusion, VDR BsmI B allele, bb genotype was associated with T1DM risk in Asians, and bb genotype was associated with T1DM risk in overall populations. However, more studies should be conducted to confirm it.


Assuntos
Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença/etnologia , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Grupos Raciais/estatística & dados numéricos , Receptores de Calcitriol/genética , Estudos de Associação Genética , Marcadores Genéticos/genética , Humanos , Prevalência , Fatores de Risco
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