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1.
PeerJ ; 12: e17271, 2024.
Article En | MEDLINE | ID: mdl-38680883

Background: We sought to create a system to evaluate the physical fitness of outstanding Chinese male boxers that included an evaluation index, fitness level criteria, and modeling. This system was then used to assess athletes' physical fitness and development. Methods: Documentation, expert interviews, questionnaires, measurements, and statistical analyses were used in this study. Results: The physical fitness evaluation system included the following three components: (1) body shape indexes (n = 4) including the backhand upper arm circumference differential, finger span height, Cottrell index, and pelvic width/shoulder width × 100; (2) body function indexes (n = 4) including relative maximum anaerobic power, relative maximal oxygen uptake, and creatine kinase and testosterone concentrations; and (3) athletic quality indexes (n = 9) including the speed strength index, the backhand straight punch strength, 3-min cumulative punching force, backhand straight punch reaction time, backhand straight punch speed, 30-m sprint, 9-min double shake jump rope, 1-min double shake jump rope, and sitting forward bend tests. A five-point grading system to evaluate physical fitness was established and an evaluation model was proposed. Conclusions: The reference values were determined to be objective and effective using a back substitution process. Individual and differential assessments reflected the athletes' level of physical fitness. The critical values were established under the best and worst conditions and the optimal values were found to be valid and effective.


Boxing , Physical Fitness , Humans , Male , Physical Fitness/physiology , Boxing/physiology , China , Athletic Performance/physiology , Young Adult , Adult , Testosterone/blood , Exercise Test/methods , Reference Values , Athletes , Creatine Kinase/blood , Oxygen Consumption/physiology , East Asian People
2.
ACS Appl Mater Interfaces ; 15(5): 7184-7195, 2023 Feb 08.
Article En | MEDLINE | ID: mdl-36701765

Bistable polymer-stabilized cholesteric liquid crystal (LC) devices have been extensively researched due to their energy-saving benefits. Compared to devices with merely transparent and light-scattering states, LC devices with controlled light absorption or changeable color functions are unquestionably more intriguing. In this paper, a polymer-stabilized ion-doped cholesteric LC and an electrochromic layer are used to fabricate a colorable device which can show four operating states: transparent, light-scattering, colored transparent, and colored light-scattering. The working principle and fabrication strategy are explained in detail. Based on the dielectric response of LC, the electrohydrodynamic effect of ion-doped LC, and the redox reaction of electrochromic materials, the transparent or light-scattering state and the colored or colorless state of the device can be regulated by controlling the alternating frequency and the direction of the electric field. The display performance related to the monomer, chiral dopant, and electrochromic layer is investigated. The content of monomer and chiral dopant affects the polymer network and pitch of cholesteric LC, which then affects the driving voltages and contrast ratio. The thickness of the electrochromic layer has a significant impact on the transmittance of the device's coloring and fading states. The sample with excellent operating states is obtained by optimizing the material and the construction, which can be widely applied in smart windows and energy-saving display devices.

3.
Plant Dis ; 2022 Nov 09.
Article En | MEDLINE | ID: mdl-36350730

Tabernaemontana bufalina Lour. is extensively cultivated as an ornamental plant in Hainan, Guangdong, and other regions of southern China. In January 2020, we observed a rust disease on T. bufalina leaves in Sanya (18.15。N and 109.30。E) Hainan, China, and the rust occurred all year-round. In the early stage of rust, yellow chlorotic spots appeared, and then uredinia on the abaxial leaf surface became visible. Uredinia (approximately 200-700 µm in diameter) were mostly yellowish-brown in color, solitary, and irregularly scattered. In the late stage of the disease, spots were connected into lesions, and eventually, the whole leaf became severely chlorotic. Urediniospores were light brown, subglobose, measured 25-30 µm × 20-25 µm. They had two pores and were echinulate with spines spaced 2-5 µm. The teliospores were naked, scattered, or aggregated on severely infected leaves. They were two-celled, measured 33-40 µm × 25-30 µm, elliptic, dark brown, and covered with tiny spines. The teliospores had a colorless pedicel at one end which was approximately 28-34 µm long and enlarged at the lower part. The morphological characteristics of the spores were consistent with the descriptions of Puccinia engleriana Henn. (Hennings 1905). In China, P. engleriana was first identified on the leaves of Tabernaemontana divaricata (L.) in Yunnan province, and recorded as new to China in 2012 (Zhuang 2012). Untill now, no leaf rust caused by P. engleriana has been reported in Hainan. Urediniospores were collected and DNA was extracted using a Quick-DNA extraction Kit (TIANGEN Biotech, Beijing, China). The nuclear large subunit (28S) region of the ribosomal DNA repeat was amplified with primers Rust28SF (Aime et al. 2018) and LR5 (Vilgalys and Hester 1990) following the protocol of Aime and McTaggart (2021). The length of the large subunit sequence was 1,010 bp. When searched the GenBank database, the sequence showed 97.07% homology to the large subunit ribosomal RNA gene (Sequence ID: MW147048.1) of P. engleriana, and 92.5% similarity with 18S ribosomal RNA gene (Sequence ID: KM249855.1) of P. hemerocallidis. This result was consistent with the morphological identification. As for the 3% difference in large subunit ribosomal RNA gene, it was speculated that it may be related to the differences of geographical distribution and host plants, as the reference P. engleriana was obtained from Tabernaemontana orientalis in Australia (Aime and McTaggart 2021). The large subunit sequence was submitted into the GenBank database, with accession No. MZ314895. T. bufalina cutting seedlings with 4 available leaves were used in the Koch's postulate test. These seedlings were planted in a greenhouse with a 14 h/10 h light/dark photoperiod at 28°C and 65% humidity. The urediniospores suspension (5107/ml in 0.05% Tween 20 solution) was sprayed on 6 healthy seedlings and other 6 seedlings were sprayed with 0.05% Tween 20 solution as a negative control. Two weeks after inoculation, leaf chlorosis and yellowish uredinia were observed on the inoculated seedlings, whereas the non-inoculated seedlings stayed healthy. To our knowledge, this is the first report of P. engleriana causing leaf rust on T. bufalina in Hainan province. This report will provide the reference for future investigation of T. bufalina leaf rust, and for further improvement on the knowledge of the geographical distribution of P. engleriana in China.

4.
Soft Matter ; 18(17): 3328-3334, 2022 May 04.
Article En | MEDLINE | ID: mdl-35385566

In this work, we investigate the three-dimensional lattice deformation of blue phase (BP) liquid crystals under electrostriction. Using the in situ measurement of light diffraction signals from a twinned crystal, we propose a method to experimentally determine the lattice constants of BPs under an electric field; the overlap angle in the diffraction pattern of BP twinning domains gives the ratio of lattice constants in the lateral direction of the field, which can be analyzed together with the Bragg reflection peak wavelength along the field direction to yield three-dimensional lattice constants. The obtained values are confirmed to show good agreement with the diffraction data measured from a converging monochromatic light. Furthermore, by applying the method to BPs in a thin cell and specifying the transitions of azimuthal orientation, three-dimensional lattice deformation of BP I crystals and evolution of the azimuthal orientation are clarified under the electrostriction. Results reveal that the BPs confined to thin films undergo discrete elongation along the field direction and the BP I crystal undergoes larger lattice deformation in the field-perpendicular directions than that along the field. Our work allows a relatively easy determination of three-dimensional lattice constants of deformed BP crystals under an electric field, and the obtained results provide important insights into the understanding of the electrostriction behaviour of BPs towards improvement of the electro-optical performance of BP devices in practical applications.

5.
Opt Express ; 29(23): 37464-37475, 2021 Nov 08.
Article En | MEDLINE | ID: mdl-34808817

A four-mode 2D/3D switchable display using a 1D/2D convertible liquid crystal (LC) lens array is proposed in this paper. The LC lens array is composed of two orthogonal LC lens arrays, with a λ/2 film in the middle to rotate the polarization by 90°. Based on the LC lens array, a four-mode 2D/3D switchable display is realized, which is switchable between the turn-off and turn-on states: when the operating voltage V1 = 0, V2 = 0, the display operates in mode I, which is 2D display; when the operating voltage V1 = 0, V2 = 0, the display operates in mode II, and the 3D display effect is in x direction; when the operating voltage V1 = 0, V2 = 0, the display operates in mode III, and the 3D display effect is in y direction; when the operating voltage V1 = 0, V2 = 0, the display operates in mode IV, the 3D display effect is in x-y plane. Experimental results indicate that the LC lens array has simple fabrication process, low operating voltage (∼5.4V), and short focal length. Moreover, based on the designed LC lens array, the 2D/3D switchable display shows no moiré pattern.

6.
Front Oncol ; 11: 633794, 2021.
Article En | MEDLINE | ID: mdl-34646755

Human papillomavirus (HPV) is a double-stranded DNA (dsDNA) virus, and its high-risk subtypes increase cancer risks. However, the mechanism of HPV infection and pathogenesis still remain unclear. Therefore, understanding the molecular mechanisms and the pathogenesis of HPV are crucial in the prevention of HPV-related cancers. In this study, we analyzed cervix squamous cell carcinoma (CESC) and head and neck carcinoma (HNSC) combined data to investigate various HPV-induced cancer common features. We showed that epidermal growth factor receptor (EGFR) was downregulated in HPV-positive (HPV+) cancer, and that HPV+ cancer patients exhibited better prognosis than HPV-negative (HPV-) cancer patients. Our study also showed that TP53 mutation rate is lower in HPV+ cancer than in HPV- cancer and that TP53 can be modulated by HPV E7 protein. However, there was no significant difference in the expression of wildtype TP53 in both groups. Subsequently, we constructed HPV-human interaction network and found that EGFR is a critical factor. From the network, we also noticed that EGFR is regulated by HPV E7 protein and hsa-miR-944. Moreover, while phosphorylated EGFR is associated with a worse prognosis, EGFR total express level is not significantly correlated with prognosis. This indicates that EGFR activation will induce a worse outcome in HPV+ cancer patients. Further enrichment analysis showed that EGFR downstream pathway and cancer relative pathway are diversely activated in HPV+ cancer and HPV- cancer. In summary, HPV E7 protein downregulates EGFR that downregulates phosphorylated EGFR and inhibit EGFR-related pathways which in turn and consequently induce better prognosis.

7.
Colloids Surf B Biointerfaces ; 188: 110783, 2020 Apr.
Article En | MEDLINE | ID: mdl-32004907

The failure of dental implants is usually caused by bacteria infection, poor bioactivity and biocompatibility. It is a common phenomenon clinically. Statherin, a salivary protein, plays a crucial role of mediator between materials and cells/bacteria. However, the conformation of statherin might be changed by the implants in vivo. In this study, we investigated the effects of statherin on the bioactivities, antibacterial abilities and biocompatibilities of the titanium metals and the reaction mechanism. We found that the conformation of statherin was mainly influenced by surface composition, surface structure, surface roughness, surface hydrophilia and Ti-OH groups of materials. Statherin could decrease the cell biocompatibility of the titanium metals including pure titanium (PT), anodic oxidation (AO), sandblasting and etching (SLA) and plasma spraying hydroxyapatite (HA) coating in HGF cell experiments, regulate the bio-mineralization ability of HA coating in SBF, and enhance the antibacterial properties of PT and HA coating. This study revealed that surface properties of materials could change the conformation of statherin, which influenced the bioactivities, antibacterial properties and biocompatibilities of the materials in return.


Anti-Bacterial Agents/metabolism , Coated Materials, Biocompatible/metabolism , Salivary Proteins and Peptides/metabolism , Titanium/metabolism , Adsorption , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Cell Line , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Dental Implants , Escherichia coli/drug effects , Escherichia coli/growth & development , Humans , Microbial Sensitivity Tests , Particle Size , Protein Conformation , Salivary Proteins and Peptides/chemistry , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Surface Properties , Titanium/chemistry , Titanium/pharmacology
8.
Nanotechnology ; 30(47): 475201, 2019 Nov 22.
Article En | MEDLINE | ID: mdl-31434061

Some enhanced performances can be obtained by doping multi-walled carbon-nanotube (MWCNT) into self-organized nematic liquid crystal (NLC). However, the dispersion of MWCNT in NLC is very few, thus the enhancement is restricted. In this work, a nickel plated MWCNT (MWCNT@Ni) is synthesized to obtain a relatively high dispersion. The morphology, element and chemical bond differences between MWCNT and MWCNT@Ni are characterized. For MWCNT@Ni, there is a layer of coaxial nickel coated on the surface of MWCNT, which weakens the interaction energy between the adjacent MWCNTs and further results in a relatively high dispersion. Moreover, MWCNT@Ni has a more orderly arrangement in NLC compared with MWCNT. The results suggest that the dielectric anisotropy of MWCNT@Ni/NLC with mass fraction of 0.01 wt% is increased by ∼3.6%, and the saturation voltage is reduced by ∼7.3%. Besides, the rise time is decreased by ∼9.5% at 5 V and 1 kHz. These performances have been improved compared with MWCNT/NLC under the same mass fraction. The effect of mass fraction of MWCNT@Ni on rise time is further investigated. As a result, the rise time is decreased by ∼16.7% as MWCNT@Ni with mass fraction of 0.10 wt% is added into NLC. In general, the method to increase dispersion of dopant in NLC is proposed, which can serve as a reference to improve the performances of NLC composites.

9.
Opt Express ; 26(7): 9254-9262, 2018 Apr 02.
Article En | MEDLINE | ID: mdl-29715879

A liquid crystal (LC) lens array with high light control power and a large aperture using a composited alignment layer is proposed. In our design, the alignment layer is not only used for getting a uniform arrangement of LC molecule, but also for getting a lens-like refractive index distribution in the LC layer when a voltage is applied. Through simple technology processes, a tunable focal length LC lens array with a millimeter scale diameter can be achieved. Furthermore, the maximum phase difference of the proposed LC lens array can achieve 105.38π. So, the proposed LC lens array has a high light control power.

10.
J Nanosci Nanotechnol ; 12(3): 1776-91, 2012 Mar.
Article En | MEDLINE | ID: mdl-22754981

Epoxy acrylate (EA) composites containing graphite oxide (GO), graphene and nitrogen-double bond functionalized graphite oxide (FGO) were fabricated using UV-radiation and electron beam radiation via in-situ polymerization. Graphene and FGO were homogenously dispersed in EA matrix and enhanced properties, including thermal stability, flame retardancy, electrical conductivity and reduced deleterious gas releasing in thermo decomposition were obtained. Microscale combustion colorimeter results illustrated improved flame retardancy; EA/FGO composites achieved a 29.7% reduction in total heat release (THR) when containing only 0.1% FGO and a 38.6% reduction in peak-heat release rate (PHRR) when containing 3% FGO. The onset decomposition temperatures were delayed and the maximum decomposition values were reduced, according to thermogravimetric analysis which indicated enhanced thermal stabilities. The electrical conductivity was increased by 6 orders of magnitude (3% graphene) and the deleterious gas released during the thermo decomposition was reduced with the addition of all the graphite samples. This study represented a new approach to functionalize GO with flame retardant elements and active curable double bond to achieve better dispersion of GO into polymer matrix to obtain nanocomposites and paved a way for achieving graphene-based materials with high-performance of graphene in enhancement of flame retardancy of polymers for practical applications.

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