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1.
Int J Occup Saf Ergon ; 30(1): 205-214, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37422729

RESUMO

A liquid-cooled garment with active cooling function can make up for deficiency of the human thermoregulatory system and passive thermal insulation of the firefighting protective suit. Fabrics treated at different inlet temperatures and pipeline intervals were applied in multilayered liquid-cooled fabric assemblies (LCFAs). The heat absorbed by the skin and the second-degree burn time were evaluated by the stored energy test under low heat radiation. Results indicated that the thermal protective performance of the LCFAs was significantly improved, with the second-degree burn time increasing more than 50% on average. There was a strong negative correlation between the thermal protective performance and cooling effect under different pipeline intervals, while the negative correlation was weak for different inlet temperatures. The results gained from this study may provide valuable insight for design of the inlet temperature and pipeline interval of a liquid-cooled system in the firefighting protective suit.


Assuntos
Regulação da Temperatura Corporal , Roupa de Proteção , Humanos , Temperatura , Temperatura Baixa , Temperatura Alta
2.
ACS Nano ; 18(1): 328-336, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38147566

RESUMO

Si-based emitters have been of great interest as an ideal light source for monolithic optical-electronic integrated circuits (MOEICs) on Si substrates. However, the general Si-based material is a diamond structure of cubic lattice with an indirect band gap, which cannot emit light efficiently. Here, hexagonal-Ge (H-Ge) nanostructures within a light-emitting metasurface consisting of a cubic-SiGe nanodisk array are reported. The H-Ge nanostructure is naturally formed within the cubic-Ge epitaxially grown on Si (001) substrates due to the strain-induced nanoscale crystal structure transformation assisted by far-from-equilibrium growth conditions. The direct-bandgap features of H-Ge nanostructures are observed and discussed, including a rather strong and linearly power-dependent photoluminescence (PL) peak around 1562 nm at room temperature and temperature-insensitive PL spectrum near room temperature. Given the direct-bandgap nature, the heterostructure of H-Ge/C-Ge, and the compatibility with the sophisticated Si technology, the H-Ge nanostructure has great potential for innovative light sources and other functional devices, particularly in Si-based MOEICs.

3.
Parasit Vectors ; 16(1): 433, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993938

RESUMO

BACKGROUND: During the early stages of Trichinella spiralis infection, macrophages predominantly undergo polarization to the M1-like phenotype, causing the host's inflammatory response and resistance against T. spiralis infection. As the disease progresses, the number of M2-type macrophages gradually increases, contributing to tissue repair processes within the host. While cysteine protease overexpression is typically associated with inflammation, the specific role of T. spiralis cathepsin L (TsCatL) in mediating macrophage polarization remains unknown. The aim of this study was to assess the killing effect of macrophage polarization mediated by recombinant T. spiralis cathepsin L domains (rTsCatL2) on newborn larvae (NBL). METHODS: rTsCatL2 was expressed in Escherichia coli strain BL21. Polarization of the rTsCatL2-induced RAW264.7 cells was analyzed by enzyme-linked immunosorbent assay (ELISA), quantitative PCR (qPCR), western blot, immunofluorescence and flow cytometry. The effect of JSH-23, an inhibitor of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), on rTsCatL2-induced M1 polarization investigated. Cytotoxic effects of polarized macrophages on NBL were observed using in vitro killing assays. RESULTS: Following the co-incubation of rTsCatL2 with RAW264.7 murine macrophage cells, qPCR and ELISA revealed increased transcription and secretion levels of inducible nitric oxide synthase (iNOS), interleukin (IL)-6, IL-1ß and tumor necrosis factor alpha (TNF-α) in macrophages. Western blot analysis showed a significant increase in iNOS protein expression, while the expression level of arginase-1 protein remained unchanged. Flow cytometry revealed a substantial increase in the number of CD86-labeled macrophages. The western blot results also indicated that rTsCatL2 increased the expression levels of phospho-NF-κB and phospho-nuclear factor-κB inhibitor alpha (IκB-α) proteins in a dose-dependent manner, while immunofluorescence revealed that rTsCatL2 induced nuclear translocation of the p65 subunit of NF-κB (NF-κB p65) protein in macrophages. The inhibitory effect of JSH-23 suppressed and abrogated the effect of rTsCatL2 in promoting M1 macrophage polarization. rTsCatL2 mediated polarization of macrophages to the M1-like phenotype and enhanced macrophage adhesion and antibody-dependent cell-mediated cytotoxicity (ADCC) killing of NBL. CONCLUSIONS: The results indicated that rTsCatL2 induces macrophage M1 polarization via the NF-κB pathway and enhances the ADCC killing of NBL. This study provides a further understanding of the interaction mechanism between T. spiralis and the host.


Assuntos
NF-kappa B , Trichinella spiralis , Camundongos , Animais , NF-kappa B/metabolismo , Trichinella spiralis/metabolismo , Larva/metabolismo , Catepsina L/metabolismo , Macrófagos/metabolismo , Escherichia coli/metabolismo , Citotoxicidade Celular Dependente de Anticorpos , Lipopolissacarídeos/farmacologia
4.
Appl Opt ; 62(13): 3477-3484, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132849

RESUMO

We propose the design of a composite device structure with germanium-based (Ge-based) waveguide photodetectors integrated with grating couplers on a silicon-on-insulator platform. The finite-difference time-domain method is used to establish simulation models and optimize the design of the waveguide detector and grating coupler. For the grating coupler, by adjusting the size parameters to the optimal value and combining the advantages of the nonuniform grating and the Bragg reflector structure, the peak coupling efficiency reaches 85% at 1550 nm and 75.5% at 2000 nm, which is, respectively, 31.3% and 14.6% higher than that of uniform grating. For the waveguide detector, a germanium-tin (GeSn) alloy was introduced to replace Ge as the active absorption layer at 1550 and 2000 nm, which not only broadened the detection range and significantly improved the light absorption of the detector but also realized the near-complete light absorption of the GeSn alloy when the device length was 10 µm. These results make it possible to miniaturize the device structure of Ge-based waveguide photodetectors.

5.
Food Chem ; 399: 134002, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36037690

RESUMO

Herein, a competitive quenching electrochemiluminescence immunosensor towards aflatoxin B1 (AFB1) detection was constructed by in-situ forming platinum nanoparticles (PtNPs) on ECL emitter COP T4VTP6 and effective ECL signal quencher Fc-CHO/Phe. In this system, cationic covalent organic polymer COP T4VTP6 emitted stronger cathode ECL signal at 765 nm, it acted as an interesting nanoreactor to immobilize PtCl62- through electrostatic adsorption, and directly in situ catalyzed the redox reaction to produce PtNPs without adding any external reducing agent, where PtNPs not only served as the substrate for antibody immobilization, but also played the role of coreaction accelerator to catalyze the production of SO4-, significantly improving more stable ECL signal. Moreover, the Fc-CHO/Phe labeled BSA-AFB1 was used for competitive reaction. Based on the efficient sensing strategy, ECL signal increased accordingly and exhibited linear signal responses with increasing AFB1, which realized a detection limit of 4.56 fg/mL, providing a promising potential on food analysis.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Técnicas Eletroquímicas , Imunoensaio , Limite de Detecção , Medições Luminescentes , Nanotecnologia , Platina
6.
Nat Commun ; 13(1): 6593, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329034

RESUMO

Strongly correlated materials often exhibit an electronic phase separation (EPS) phenomena whose domain pattern is random in nature. The ability to control the spatial arrangement of the electronic phases at microscopic scales is highly desirable for tailoring their macroscopic properties and/or designing novel electronic devices. Here we report the formation of EPS nanoscale network in a mono-atomically stacked LaMnO3/CaMnO3/PrMnO3 superlattice grown on SrTiO3 (STO) (001) substrate, which is known to have an antiferromagnetic (AFM) insulating ground state. The EPS nano-network is a consequence of an internal strain relaxation triggered by the structural domain formation of the underlying STO substrate at low temperatures. The same nanoscale network pattern can be reproduced upon temperature cycling allowing us to employ different local imaging techniques to directly compare the magnetic and transport state of a single EPS domain. Our results confirm the one-to-one correspondence between ferromagnetic (AFM) to metallic (insulating) state in manganite. It also represents a significant step in a paradigm shift from passively characterizing EPS in strongly correlated systems to actively engaging in its manipulation.

7.
Anal Bioanal Chem ; 414(17): 4837-4847, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35513458

RESUMO

Herein, we fabricated a label-free ECL immunosensor for aflatoxin B1 (AFB1) detection. In this system, a small organic aggregation-induced electrochemiluminescence luminophore, 2,5-di-tetraphenylethylene-ylthiazolo [5,4-d] thiazole, was designed, named TPETTZ. Polyaniline-wrapped TiO2 nanoparticles (PANI/TiO2 NPs) complex was synthesized through one-step in situ oxidation polymerization of aniline, and performed excellent electrical conductivity and abundant amino groups. As an ECL accelerator, TiO2 nanoparticles (TiO2 NPs) promoted the oxidation of tri-n-propylamine (TPA) to generate more TPA•; in addition, it also acted as a donor to improve the ECL intensity of TPETTZ (acceptor) through electrochemiluminescence resonance energy transfer (ECL-RET). Encouraged by the above, under the existence of TPA, TPETTZ displayed a strong and continuously stable ECLanode signal due to the introduction of PANI/TiO2 NPs. Therefore, the immunosensor was constructed for AFB1 detection based on the quenching effect of target on the ECL signal, and a linearly decreasing ECL signal was obtained as the increasement of AFB1 in the range of 75 fg/mL to 100 ng/mL, with a lower detection limit of 27.5 fg/mL. Moreover, the as-prepared sensing platform performed a satisfactory anti-interference, stability, and reproducibility, and appeared a good accuracy in walnut sample analysis, presenting a promising application in the future.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanopartículas , Aflatoxina B1/análise , Técnicas Eletroquímicas , Ouro , Imunoensaio , Limite de Detecção , Medições Luminescentes , Reprodutibilidade dos Testes , Titânio
8.
Orthop Surg ; 14(1): 129-138, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35023317

RESUMO

OBJECTIVE: To investigate the role of dementia in pneumonia among geriatric patients with hip fracture and further develop an algorithm for stratifying risk of developing postoperative pneumonia. METHODS: The algorithm was developed after retrospectively analyzing 1344 hip fracture patients in the National Clinical Research Center for Orthopedics, Sports Medicine, and Rehabilitation from 1992 to 2012. Twenty-eight variables were analyzed for evaluating the ability to predict postoperative pneumonia. The validation of the algorithm was performed in the MIMIC-III database after enrolling 235 patients. RESULTS: One thousand five hundred and seventy-nine patients were enrolled, 4.69% patients had postoperative pneumonia in our hospital, and 17.02% suffered pneumonia in the MIMIC-III database. Dementia patients had more postoperative pneumonia (12.68% vs 4.24%, P = 0.0075), as compared with patients without dementia. The algorithm included nine predictors: dementia, age, coronary heart disease, the American Society of Anesthesiologists score, surgical method, mechanical ventilation, anemia, hypoproteinemia, and high creatinine. Internal validation showed the algorithm with dementia could improve predictive performance, while external validation found the algorithm with or without dementia both had similar and good predictive ability. CONCLUSIONS: The algorithm has the potential to be a pragmatic risk prediction tool to calculate risk of pneumonia in clinical practice and it may also be applicable in critically ill hip fracture patients with dementia.


Assuntos
Demência/complicações , Serviços de Saúde para Idosos , Fraturas do Quadril/cirurgia , Pneumonia/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Diagnóstico Precoce , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco
9.
Endokrynol Pol ; 73(1): 121-130, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34855195

RESUMO

INTRODUCTION: Under normal physiological conditions, insulin exhibits a series of important biological functions and roles. Recent studies have shown that insulin is also closely related to the occurrence and development of lung cancer. However, until now, the cellular properties of insulin/insulin receptor (IR) on lung cancer have not been fully revealed. MATERIAL AND METHODS: Indirect immunofluorescence, western blot, and other techniques have been used to identify the biological activity of insulin on lung cancer cell lines. RESULTS: The biological activities of insulin are closely related to its cell behaviour. Therefore, we used lung cancer cell lines as a model to explore the cellular behaviour and properties of insulin/IR in the current study, and the results showed that the IR could internalize into lung cancer cells, and it can also transport into the cell nuclei under insulin treatment. Further study showed that nuclear-localized IR could promote the proliferation of lung cancer cells. CONCLUSION: Taken together, this study shows that IR's nuclear localization is closely related to cell proliferation. This work lays the foundation for further research on the relationship between insulin and the occurrence and development of lung cancer.


Assuntos
Neoplasias Pulmonares , Receptor de Insulina , Núcleo Celular/metabolismo , Proliferação de Células , Humanos , Insulina/metabolismo , Insulina/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Receptor de Insulina/metabolismo
10.
Rev Sci Instrum ; 92(11): 113906, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34852506

RESUMO

Oxide superlattices often exhibit emergent physical properties that are desirable for future information device applications. The most common growth technique for fabrication of oxide superlattices is pulsed laser deposition (PLD), which is convenient yet powerful for the growth of various oxide superlattices. However, the sample size prepared by PLD is rather small confined by the plasmon plume, which greatly limits its potential for device applications. Here, we design a PLD system that is capable of fabricating large-sized oxide superlattices with high uniformity. Specifically, during growth, the laser beam scans the target surface by combining the pitch and yaw angle rotation of the high reflective mirror and the linear motion of the focus lens. A SiC susceptor is placed in between the sample holder and the substrate to improve the large area infrared heating efficiency. Using such a system, droplet-free 10 × 10 mm2 [(LSMO)12/(PCMO)6]7 superlattices are epitaxially grown with the same period of superlattices across the whole sample areas. The high uniformity of the superlattices is further illustrated by near identical physical properties of all regions of the superlattice films. The present PLD system can be used to grow various kinds of oxide superlattices with the area size as large as 2 in., which is highly useful for device applications of oxides.

11.
Diabetes ; 70(5): 1170-1184, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33627322

RESUMO

Cutaneous wound healing is a fundamental biologic and coordinated process, and failure to maintain this process contributes to the dysfunction of tissue homeostasis, increasing the global burden of diabetic foot ulcerations. However, the factors that mediate this process are not fully understood. Here, we identify the pivotal role of dedicator of cytokinesis 5 (Dock5) in keratinocyte functions contributing to the process of skin wound healing. Specifically, Dock5 is highly upregulated during the proliferative phase of wound repair and is predominantly expressed in epidermal keratinocytes. It regulates keratinocyte adhesion, migration, and proliferation and influences the functions of extracellular matrix (ECM) deposition by facilitating the ubiquitination of transcription factor ZEB1 to activate laminin-332/integrin signaling. Genetic ablation of Dock5 in mice leads to attenuated reepithelialization and granulation tissue formation, and Dock5 overexpression-improved skin repair can be abrogated by LAMA3 knockdown. Importantly, Dock5 expression in the skin edge is reduced in patients and animal models of diabetes, further suggesting a direct correlation between its abundance and healing capability. The rescue of Dock5 expression in diabetic mice causes a significant improvement in reepithelialization, collagen deposition, ECM production, and granulation. Our study provides a potential therapeutic target for wound healing impairment during diabetes.


Assuntos
Adesão Celular/fisiologia , Proliferação de Células/fisiologia , Queratinócitos/citologia , Queratinócitos/metabolismo , Animais , Western Blotting , Adesão Celular/genética , Proliferação de Células/genética , Células Cultivadas , Citocinese/genética , Citocinese/fisiologia , Imunofluorescência , Humanos , Hibridização In Situ , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Cicatrização/genética , Cicatrização/fisiologia
13.
J Med Virol ; 93(1): 506-512, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32644223

RESUMO

To investigate the factors associated with the duration of severe acute respiratory syndrome coronavirus 2 RNA shedding in patients with coronavirus disease 2019 (COVID-19). A retrospective cohort of COVID-19 patients admitted to a designated hospital in Beijing was analyzed to study the factors affecting the duration of viral shedding. The median duration of viral shedding was 11 days (IQR, 8-14.3 days) as measured from illness onset. Univariate regression analysis showed that disease severity, corticosteroid therapy, fever (temperature>38.5°C), and time from onset to hospitalization were associated with prolonged duration of viral shedding (P < .05). Multivariate regression analysis showed that fever (temperature>38.5°C) (OR, 5.1, 95%CI: 1.5-18.1), corticosteroid therapy (OR, 6.3, 95%CI: 1.5-27.8), and time from onset to hospitalization (OR, 1.8, 95%CI: 1.19-2.7) were associated with increased odds of prolonged duration of viral shedding. Corticosteroid treatment, fever (temperature>38.5°C), and longer time from onset to hospitalization were associated with prolonged viral shedding in COVID-19 patients.


Assuntos
COVID-19/virologia , SARS-CoV-2/fisiologia , Eliminação de Partículas Virais/fisiologia , Corticosteroides/uso terapêutico , Adulto , COVID-19/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/isolamento & purificação , Fatores de Risco , Fatores de Tempo , Tratamento Farmacológico da COVID-19
14.
Mediators Inflamm ; 2020: 4539035, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32377160

RESUMO

AIMS: To assess the maresin 1 (MaR1) contents in type 2 diabetic patients with or without diabetic foot ulcer and to analyze the association of MaR1 concentrations with several metabolism-related parameters. METHODS: Plasma MaR1 concentrations were analyzed in 96 subjects with normal glucose tolerant (NC, n = 43), type 2 diabetes (T2DM, n = 40), or diabetic foot ulcer (DFU, n = 13). The intravenous glucose tolerance test (IVGTT) and biochemical parameters were measured in all participants. RESULTS: Plasma MaR1 concentrations were significant decreased in type 2 diabetes patient with or without DFU compared with NC (both P < 0.001) and were lowest in DFU patients among these 3 groups. (DFU vs. T2DM, P < 0.05). Plasma MaR1 concentrations were negatively correlated with BMI, waist circumference (Wc), waist hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), LDL-c, FPG, 2hPG, HbA1c, and homeostasis model assessment for insulin resistance (HOMA-IR) (all P < 0.05) and were positively correlated with HDL-c, acute insulin response (AIR), area under the curve of the first-phase (0-10 min) insulin secretion (AUC), and homeostasis model assessment for beta-cell function (HOMA-ß) (all P < 0.05). After adjusting for age and sex, Wc, WHR, TG, FPG, 2hPG, HbA1c, HOMA-IR, AIR, AUC, and HOMA-ß remain statistically significant (all P < 0.05). CONCLUSIONS: Plasma MaR1 concentration were decreased in T2DM with or without DFUs and were the lowest in DFU patients. The decreased plasma MaR1 strongly associated with obesity, impaired glucose and lipid metabolism, reduced first-phase of glucose-stimulated insulin secretion, and enhanced insulin resistance.


Assuntos
Pé Diabético/sangue , Ácidos Docosa-Hexaenoicos/sangue , Adulto , Idoso , Feminino , Glucose/metabolismo , Humanos , Resistência à Insulina , Metabolismo dos Lipídeos , Masculino , Pessoa de Meia-Idade
15.
Proc Natl Acad Sci U S A ; 117(13): 7090-7094, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32179681

RESUMO

Electronic phase separation in complex oxides is the inhomogeneous spatial distribution of electronic phases, involving length scales much larger than those of structural defects or nonuniform distribution of chemical dopants. While experimental efforts focused on phase separation and established its correlation with nonlinear responses under external stimuli, it remains controversial whether phase separation requires quenched disorder for its realization. Early theory predicted that if perfectly "clean" samples could be grown, both phase separation and nonlinearities would be replaced by a bicritical-like phase diagram. Here, using a layer-by-layer superlattice growth technique we fabricate a fully chemically ordered "tricolor" manganite superlattice, and compare its properties with those of isovalent alloyed manganite films. Remarkably, the fully ordered manganite does not exhibit phase separation, while its presence is pronounced in the alloy. This suggests that chemical-doping-induced disorder is crucial to stabilize the potentially useful nonlinear responses of manganites, as theory predicted.

16.
ACS Appl Bio Mater ; 3(12): 8933-8942, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35019569

RESUMO

9,10-Diphenylanthracene cubic nanoparticles (DPA CNPs) with aggregation-induced emission characteristic (AIEgens) were synthesized through a facile reprecipitation method; then, a bright and stable electrochemiluminescence (ECL) signal can be observed when the DPA CNPs were modified at the glassy carbon electrode (GCE) in the presence of Tri-n-propylamine (TPA). This phenomenon is ascribed to the molecules with restricted movement that greatly blocked the energy leakage during the relaxation of the excited state, which facilitated the emission of energy in the form of photons. In addition, the size confinement effect of DPA CNPs in the aggregated state effectively enhanced the ECL emission. The application of DPA CNPs with AIE characteristics in an electrochemiluminescence immunosensor has not been reported. In this contribution, a free-label aggregation-induced electrochemiluminescence immunosensor based on DPA CNPs was fabricated and a simple strategy for ultrasensitive detection of aflatoxin B1 (AFB1) was proposed. The ECL signal is quenched linearly in the range of 0.01 pg/mL to 100 ng/mL for AFB1, and the detection limit is 3 fg/mL. In summary, the prepared sensor exhibits high sensitivity, acceptable accuracy, good anti-interference ability and stability, and satisfactory detection toward AFB1 in walnut samples. Therefore, the fabricated immunosensor will have significant applications in the fields of food, medicine, and so on.

17.
Nat Commun ; 10(1): 3877, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462635

RESUMO

Tailoring molecular spinterface between novel magnetic materials and organic semiconductors offers promise to achieve high spin injection efficiency. Yet it has been challenging to achieve simultaneously a high and nonvolatile control of magnetoresistance effect in organic spintronic devices. To date, the largest magnetoresistance (~300% at T = 10 K) has been reached in tris-(8-hydroxyquinoline) aluminum (Alq3)-based organic spin valves (OSVs) using La0.67Sr0.33MnO3 as a magnetic electrode. Here we demonstrate that one type of perovskite manganites, i.e., a (La2/3Pr1/3)5/8Ca3/8MnO3 thin film with pronounced electronic phase separation (EPS), can be used in Alq3-based OSVs to achieve a large magnetoresistance (MR) up to 440% at T = 10 K and a typical electrical Hanle effect as the Hallmark of the spin injection. The contactless magnetic field-controlled EPS enables us to achieve a nonvolatile tunable MR response persisting up to 120 K. Our study suggests a new route to design high performance multifunctional OSV devices using electronic phase separated manganites.

18.
J Tradit Complement Med ; 9(3): 215-220, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31193929

RESUMO

Addicted drugs like nicotine affect autonomic nervous system that results in arrhythmia and other cardiovascular diseases. Notable effects of Zen meditation on autonomic nervous system have been reported during the past decade. Holistic Detox Association (HDA) in Taiwan offered Zen-meditation program to drug addicts as the core scheme among a variety of drug addiction treatments. This paper reports the results of quantifying the cardiorespiratory interactions and autonomic nervous system function to evaluate the on-site effect of Zen meditation on drug rehab. Methods and schemes for quantifying time-domain heart rate variability were employed to electrocardiograph and respiratory signals. Peak-valley method was developed to quantify the respiratory sinus arrhythmia (RSA) behavior. Poincaré Plot Analysis was adopted to evaluate the cardiorespiratory functioning. Among 18 voluntary drug addicts during the 10-minute Zen meditation session, about two-third subjects have significant improvement in autonomic nervous system function characterized by heart rate variability (SDNN, RMSSD and pNN50). Group average of RSA increases from 33.43 ms(Rest) to 69.14 ms(AR Zen meditation). Poincaré-plot analysis reveals the improvement of SD1, SD2 and SD2/SD1 by respectively 14.7%, 19.8% and 8.8%. The group averages of all the parameters exhibit significantly positive changes in the 10-minute session of abdominal-respiration Zen meditation. Even the subject with heart transplant showed the improvement of all the quantitative indicators during the AR Zen meditation.

19.
Technol Cult ; 60(2): 616-624, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31204349

RESUMO

Using cross-cultural comparison, Joseph Needham composed a "connected history" of Chinese science and technology in global context, so that his Science and Civilisation in China (SCC) offered a refreshing view of science and technology to readers. In the SCC's subvolume on mechanical engineering (vol. 4, part 2), for example, the authors identified many inventions in premodern China, including the efficient harness, the gimbal, and the waterwheel linkwork escapement. Needham further tried to verify the possible origin and transregional dissemination (including stimulus diffusion) of such inventions as the astronomical clockwork and the interconversion of rotary and rectilinear motion in Eurasia. Although it was difficult to make satisfying arguments about the impact of Chinese knowledge on any European invention, Needham's methodologies, and even his enlightening speculations, are of real significance for present and future scholarship.

20.
Proc Natl Acad Sci U S A ; 116(10): 4141-4146, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30787195

RESUMO

Characterization of the onset of a phase transition is often challenging due to the fluctuations of the correlation length scales of the order parameters. This is especially true for second-order structural-phase transition due to minute changes involved in the relevant lattice constants. A classic example is the cubic-to-tetragonal second-order phase transition in SrTiO3 (STO), which is so subtle that it is still unresolved. Here, we demonstrate an approach to resolve this issue by epitaxially grown rhombohedral La0.7Sr0.3MnO3 (LSMO) thin films on the cubic STO (100) substrate. The shear strain induced nanotwinning waves in the LSMO film are extremely sensitive to the cubic-to-tetragonal structural-phase transitions of the STO substrate. Upon cooling from room temperature, the development of the nanotwinning waves is spatially inhomogeneous. Untwinned, atomically flat domains, ranging in size from 100 to 300 nm, start to appear randomly in the twinned phase between 265 and 175 K. At ∼139 K, the untwinned, atomically flat domains start to grow rapidly into micrometer scale and finally become dominant at ∼108 K. These results indicate that the low-temperature tetragonal precursor phase of STO has already nucleated at 265 K, significantly higher than the critical temperature of STO (∼105 K). Our work paves a pathway to visualize the onset stages of structural-phase transitions that are too subtle to be observed using direct-imaging methods.

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