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1.
BMC Med Imaging ; 24(1): 122, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789963

RESUMO

In response to the low real-time performance and accuracy of traditional sports injury monitoring, this article conducts research on a real-time injury monitoring system using the SVM model as an example. Video detection is performed to capture human movements, followed by human joint detection. Polynomial fitting analysis is used to extract joint motion patterns, and the average of training data is calculated as a reference point. The raw data is then normalized to adjust position and direction, and dimensionality reduction is achieved through singular value decomposition to enhance processing efficiency and model training speed. A support vector machine classifier is used to classify and identify the processed data. The experimental section monitors sports injuries and investigates the accuracy of the system's monitoring. Compared to mainstream models such as Random Forest and Naive Bayes, the SVM utilized demonstrates good performance in accuracy, sensitivity, and specificity, reaching 94.2%, 92.5%, and 96.0% respectively.


Assuntos
Traumatismos em Atletas , Aprendizado Profundo , Máquina de Vetores de Suporte , Humanos , Traumatismos em Atletas/diagnóstico por imagem , Gravação em Vídeo , Sensibilidade e Especificidade , Algoritmos
2.
J Am Chem Soc ; 143(34): 13548-13556, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34406749

RESUMO

The spontaneous freezing of microdroplets around 233 K has long been regarded as the occurrence of homogeneous ice nucleation. The corresponding temperature has been directly regarded as the homogeneous ice nucleation temperature, which is an intrinsic character of water. However, many recent investigations indicate that the spontaneous freezing may be still induced by surfaces of the water microdroplets or the residual impurities inside. Therefore, it is highly desired to reveal with solid evidence the exact origin of the spontaneous freezing. Here we show with no ambiguity that the spontaneous freezing between 233 and 235 K is actually triggered by the surface of microdroplets, as the nucleation rate is found to be proportional to the surface area of droplets, via systematically investigating the freezing of water droplets with varying sizes under various cooling rates followed by a new approach in data analysis. The conclusion is further consolidated by published experimental data from other groups when using our data analysis approach. This study is critical for understanding the sources of "no-man's land" and features of homogeneous nucleation, as well as studying the structure and properties of deeply supercooled liquid water.

3.
Chem Commun (Camb) ; 55(45): 6413-6416, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31094369

RESUMO

The capability of mediating ice nucleation is pertinent to a broad range of fields. Herein, inspired by metal-catechol coordination found in adhesive proteins in which catechol moieties can construct strong complexes with a diverse array of metal ions, we develop a platform for mediating ice nucleation based on metal-catechol complexes and demonstrate that ice nucleation can be successively mediated by varying the characteristics and valence of the metal in metal-catechol complexes.

4.
ACS Appl Mater Interfaces ; 10(2): 1957-1962, 2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29276886

RESUMO

We designed 12-amino acid peptides as antifreeze protein (AFP) mimetics and tuned the antifreeze activity of the peptides by their structures. Moreover, these short peptides were first immobilized to surfaces as an anti-icing coating. We discovered that the peptides with higher antifreeze activity exhibited better anti-icing performance. It is the first time that short peptides were successfully applied to fabricate anti-icing surfaces, which is certainly advantageous in comparison to the AFP anti-icing coatings previously reported.

5.
Langmuir ; 33(38): 9590-9597, 2017 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-28841793

RESUMO

We develop a simple approach for the preparation of oil/water separation material based on the reduced graphene oxide. First, the graphene oxide (GO) is coated on the commercially available wire mesh. The treatment of O2 plasma is exploited to open the pores from the back side using the wire mesh as a ready-made mask, and the GO-coated mesh is subjected to the thermal annealing at 200 °C for 2 h to form stable superhydrophobic reduced graphene oxide (RGO) coating. The as-prepared mesh has excellent stability and reusability and the separation selectivity is above 98% for a variety of mixtures of oil and water. Meanwhile, the as-prepared RGO@mesh-300 shows stable and robust superhydrophobic properties including the stability of long-term storage, the resistance to high temperatures, high humidities, and mechanical abrasion. It is expected that this method of fabricating superhydrophobic materials can find more practical applications, especially in the oil/water separation.

6.
ACS Omega ; 2(5): 2047-2054, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457559

RESUMO

A versatile, convenient, and cost-effective method that can be used for grafting anti-icing materials onto different surfaces is highly desirable. Based on mussel-inspired chemistry, the anti-icing coating with extremely low ice adhesion is enabled by constructing a self-sustainable lubricating layer, achieved via modifying solid substrates with a highly hydrophilic conjugate of poly(acrylic acid)-dopamine. Both unfreezable and freezable water remain liquidlike at subzero conditions and synergistically fulfill the role of lubrication for reducing the ice adhesion. The anti-icing coatings show excellent stability in harsh environments and durability after the cross-linking. More importantly, this coating can be applied to various substrates and is of great promise for practical applications.

7.
Cell Rep ; 17(2): 448-457, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27705793

RESUMO

Adult tissue-specific stem cells (SCs) mediate tissue homeostasis and regeneration and can give rise to all lineages in the corresponding tissue, similar to the early progenitors that generate organs in the first place. However, the developmental origins of adult SCs are largely unknown. We recently identified thymosphere-forming stem cells (TSFCs) in the adult mouse thymus, which display genuine stemness features and can generate the two major thymic epithelial cell lineages. Here, we show that embryonic TSFCs possess stemness features but differ from adult TSFCs in surface marker profile. Our findings support the model of a continuous thymic SC lineage that is maintained throughout ontogeny. TGF-ß signaling differentially affects embryonic versus adult thymosphere formation, suggesting that thymic epithelial SC potency depends on both developmental stage and environmental signals. Collectively, our findings suggest that embryonic TSFCs contribute to an adult SC pool and that TSFC plasticity is controlled by TGF-ß signaling.


Assuntos
Células-Tronco Embrionárias/citologia , Células Epiteliais/citologia , Timo/citologia , Fator de Crescimento Transformador beta/genética , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Células-Tronco Embrionárias/metabolismo , Células Epiteliais/metabolismo , Camundongos , Regeneração/genética , Transdução de Sinais , Timo/crescimento & desenvolvimento
8.
Adv Mater ; 28(25): 5008-12, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27119590

RESUMO

Supercharged unfolded polypeptides (SUPs) are exploited for controlling ice nucleation via tuning the nature of charge and charge density of SUPs. The results show that positively charged SUPs facilitate ice nucleation, while negatively charged ones suppress it. Moreover, the charge density of the SUP backbone is another parameter to control it.


Assuntos
Peptídeos/química , Gelo , Água
9.
Oncol Rep ; 35(2): 1170-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26573761

RESUMO

MicroRNA (miR)-106b~25 cluster regulates bypass of doxorubicin and γ-radiation induced senescence by downregulation of the E-cadherin transcriptional activator EP300. We asked whether upregulation of miR-106~25 cluster generates cells with a truly multidrug resistant (MDR) phenotype and whether this is due to upregulation of the ATP-binding cassette (ABC) transporter P-glycoprotein. We used minimally transformed mammary epithelial breast cancer cells (MTMECs) in which the miR-106b~25 cluster was experimentally upregulated by lentiviral transfection or in which hairpins targeting either EP300 or E-cadherin mRNAs have been expressed with lentiviruses. We find that overexpression of miR-106b~25 cluster led to the generation of MDR MTMECs (resistant to etoposide, colchicine and paclitaxel). Paclitaxel resistance was also studied after experimental downregulation of EP300 or E-cadherin. However none of these cells overexpressed P-glycoprotein or where able to efflux a fluorescent derivative of paclitaxel, making this phenotype drug-transporter independent. Paclitaxel treatment in MTMECs led to an increase in early apoptotic cells (Annexin V-positive), activation of caspase-9 and increase in the proportion of cells at the G2/M phase of the cell cycle. However, MTMEC overexpressing miR-106b~25 cluster, or with EP300 or E-cadherin downregulated, showed less activation of apoptosis, caspase-9 and caspase-3/-7 activities. Thus, miR-106b~25 cluster controls transporter-independent MDR by apoptosis evasion via downregulation of EP300.


Assuntos
Antineoplásicos/farmacologia , Mama/citologia , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteína p300 Associada a E1A/biossíntese , Células Epiteliais/efeitos dos fármacos , MicroRNAs/genética , Proteínas de Neoplasias/genética , RNA Neoplásico/genética , Transportadores de Cassetes de Ligação de ATP , Apoptose , Caderinas/biossíntese , Caderinas/genética , Linhagem Celular Transformada , Colchicina/farmacologia , Regulação para Baixo , Doxorrubicina/farmacologia , Proteína p300 Associada a E1A/genética , Células Epiteliais/efeitos da radiação , Etoposídeo/farmacologia , Raios gama , Humanos , Família Multigênica , Proteínas de Neoplasias/fisiologia , Paclitaxel/farmacologia , Fenótipo , Transdução Genética , Ensaio Tumoral de Célula-Tronco
10.
Curr Med Res Opin ; 31(12): 2313-23, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26402735

RESUMO

OBJECTIVE: New P2Y12 inhibitors, classified as oral (prasugrel and ticagrelor) and intravenous (cangrelor and elinogrel) drugs, have shown improved antithrombotic effects compared with clopidogrel in patients with acute coronary syndrome (ACS) or patients undergoing percutaneous coronary intervention (PCI) in landmark trials. The purpose of this study was to perform a meta-analysis of randomized trials that compared new P2Y12 inhibitors with clopidogrel to determine their efficacy and safety in patients undergoing PCI. METHODS: Randomized controlled trials of at least 4 weeks, comparing new P2Y12 inhibitors with clopidogrel in PCI, were identified using the electronic databases Cochrane Central Register of Controlled Trials, Medline, PubMed, Web of Science, and Google Scholar from January 1, 1980, to July 31, 2014. MAIN OUTCOME MEASURES: The primary efficacy endpoints were all-cause death and major adverse cardiovascular events (MACEs). The primary safety endpoint was thrombolysis in myocardial infarction (TIMI) major bleeding. RESULTS: Twelve studies including 71,097 patients met the inclusion criteria. New P2Y12 inhibitors significantly reduced all-cause death (odds ratio [OR]: 0.81; 95% confidence interval [CI] 0.73-0.90, p < 0.0001), MACEs (OR 0.81; 95% CI 0.73-0.90, p < 0.0001), stent thrombosis (OR 0.58; 95% CI 0.49-0.69, p < 0.00001), myocardial infarctions (OR 0.87; 95% CI 0.76-0.99, p = 0.03) and cardiovascular death (OR 0.82; 95% CI 0.73-0.92, p = 0.001) compared with clopidogrel. There were no significant differences between stroke (OR 0.87; 95% CI 0.72-1.05, p = 0.14) and major bleeding events (OR 1.22; 95% CI 0.99-1.52, p = 0.06) between the new P2Y12 inhibitor and clopidogrel groups. CONCLUSION: New P2Y12 inhibitors decreased death in patients undergoing PCI compared with clopidogrel with a considerable safety and tolerability profile; however, the risk/benefit ratio of ischemic and bleeding events should be further investigated.


Assuntos
Inibidores da Agregação Plaquetária/uso terapêutico , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Ticlopidina/análogos & derivados , Síndrome Coronariana Aguda/terapia , Clopidogrel , Hemorragia/induzido quimicamente , Humanos , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea/métodos , Inibidores da Agregação Plaquetária/efeitos adversos , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Ticlopidina/efeitos adversos , Ticlopidina/uso terapêutico
11.
Int J Cardiol ; 177(3): 780-5, 2014 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-25466565

RESUMO

This meta-analysis aimed to evaluate the efficacy of trimetazidine in combination with other anti-anginal drugs versus other anti-anginal drugs in the treatment of stable angina pectoris (SAP). Randomized controlled trials (RCTs) published in English and Chinese were retrieved from computerized databases: Embase, PubMed, and CNKI. Primary outcomes consist of clinical parameters (numbers of weekly angina attacks and nitroglycerin use) and ergometric parameters (time to 1mm ST-segment depression, and total work (in Mets) and exercise duration (in seconds) at peak exercise) in stable angina pectoris treated by trimetazidine or not. The quality of studies was evaluated using Jadad score. Data analysis of 13 studies was performed using Stata 12.0 software. Results showed that treatment of trimetazidine and other anti-anginal drugs was associated with a smaller weekly mean number of angina attacks (WMD=-0.95, 95%CI: -1.30 to -0.61, Z=5.39, P<0.001), fewer weekly nitroglycerin use (WMD=-0.98, 95%CI: -1.44 to -0.52, Z=4.19, P<0.001), longer time to 1mm ST-segment depression (WMD=0.30, 95%CI: 0.17 to 0.43, Z=4.46, P<0.001), higher total work (WMD=0.82, 95%CI: 0.44 to 1.20, Z=4.22, P<0.001) and longer exercise duration at peak exercise (WMD=49.81, 95%CI: 15.04 to 84.57, Z=6.38, P<0.001) than treatment of other anti-anginal drugs for stable angina pectoris. Sensitivity analysis was performed. Sub-group analysis showed that treatment duration was not a significant moderator and patients treated within 8 weeks and above 12 weeks had no difference in the outcomes addressed in this meta-analysis. No publish bias was detected. This meta-analysis confirms the efficacy of trimetazidine in the treatment of stable angina pectoris, in comparison with conventional antianginal agents, regardless of treatment duration.


Assuntos
Angina Pectoris/diagnóstico , Angina Pectoris/tratamento farmacológico , Trimetazidina/uso terapêutico , Vasodilatadores/uso terapêutico , Angina Pectoris/epidemiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Resultado do Tratamento
12.
Langmuir ; 30(31): 9436-41, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-25066958

RESUMO

Though patterned ultrathin polymer films (<100 nm) are of great importance in the fields of sensors and nanoelectronic devices, the fabrication of patterned ultrathin polymer films remains a great challenge. Herein, patterned ultrathin polymer films are fabricated facilely on hydrophobic substrates with different hydrophilic outline patterns by the pinning of three-phase contact lines of polymer solution on the hydrophilic outlines. This method is universal for most of the water-soluble polymers, and poly(vinyl alcohol) (PVA) has been selected as a model polymer due to its biocompatibility and good film-forming property. The results indicate that the morphologies of ultrathin polymer films can be precisely adjusted by the size of the hydrophilic outline pattern. Specifically, patterned hydrophilic outlines with sizes of 100, 60, and 40 µm lead to the formation of concave-shaped ultrathin PVA films, whereas uniform ultrathin PVA films are formed on 20 and 10 µm patterned substrates. The controllabilities of morphologies can be interpreted through the influences of the slip length and coffee ring effect. Theoretical analysis shows that when the size of the hydrophilic outline patterns is smaller than a critical value, the coffee ring effect disappears and uniform patterned ultrathin polymer films can be formed for all polymer concentrations. These results provide an effective methodology for the fabrication of patterned ultrathin polymer films and enhance the understanding of the coffee ring effect.


Assuntos
Álcool de Polivinil/síntese química , Interações Hidrofóbicas e Hidrofílicas , Álcool de Polivinil/química
13.
Langmuir ; 28(29): 10749-54, 2012 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-22741592

RESUMO

Understanding the role played by solid surfaces in ice nucleation is a significant step toward designing anti-icing surfaces. However, the uncontrollable impurities in water and surface heterogeneities remain a great challenge for elucidating the effects of surfaces on ice nucleation. Via a designed process of evaporation, condensation, and subsequent ice formation in a closed cell, we investigate the ice nucleation of ensembles of condensed water microdroplets on flat, solid surfaces with completely different wettabilities. The water microdroplets formed on flat, solid surfaces by an evaporation and condensation process exclude the uncontrollable impurities in water, and the effects of surface heterogeneities can be minimized through studying the freezing of ensembles of separate and independent water microdroplets. It is found that the normalized surface ice nucleation rate on a hydrophilic surface is about 1 order of magnitude lower than that on a hydrophobic surface. This is ascribed to the difference in the viscosity of interfacial water and the surface roughness.

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