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1.
Materials (Basel) ; 16(21)2023 Oct 31.
Article in English | MEDLINE | ID: mdl-37959585

ABSTRACT

Simulating the mechanical behavior of cellular materials stands as a pivotal step in their practical application. Nonetheless, the substantial multitude of unit cells within these materials necessitates a considerable finite element mesh, thereby leading to elevated computational expenses and requisites for formidable computer configurations. In order to surmount this predicament, a novel and straightforward equivalent calculation method is proposed for the computation of mechanical properties concerning both random and ordered hyper-elastic cellular materials. By amalgamating the classical finite element approach with the distribution attributes of cells, the proposed equivalent calculation method adeptly captures the deformation modes and force-displacement responses exhibited by cell materials under tensile and shear loads, as predicted through direct numerical simulation. This approach reflects the deformation characteristics induced by micro-unit cells, elucidates an equivalent principle bridging cellular materials and equivalent materials, and substantially curtails exhaustive computational burdens. Ultimately, this method furnishes an equivalent computational strategy tailored for the engineering applications of cellular materials.

2.
ACS Appl Mater Interfaces ; 15(42): 49583-49594, 2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37823823

ABSTRACT

The performance of contact resistive pressure sensors heavily relies on the intrinsic characteristics of the active layers, including the mechanical surface structure, conductivity, and elastic properties. However, efficiently and simply regulating the conductivity, morphology, and modulus of the active layers has remained a challenge. In this study, we introduced electro-polymerized polypyrrole (ePPy) to design flexible contact piezoresistive sensors with tailored intrinsic properties. The customizable intrinsic property of ePPy was comprehensively illustrated on the chemical and electronic structure scale, and the impact of ePPy's intrinsic properties on the sensing performance of the device was investigated by determining the correlation between resistivity, roughness, and device sensitivity. Due to the synergistic effects of roughness, conductivity, and elastic properties of the active layers, the flexible ePPy-based pressure sensor exhibited high sensitivity (3.19 kPa-1, 1-10 kPa, R2 = 0.97), fast response time, good durability, and low power consumption. These advantages allowed the sensor to offer an immediate response to human motion such as finger-bending and grasping movements, demonstrating the promising potential of tailorable ePPy-based contact piezoresistive sensors for wearable electronic applications.

3.
Platelets ; 31(1): 94-102, 2020.
Article in English | MEDLINE | ID: mdl-30810451

ABSTRACT

The aim of this study was to investigate the association between nadir platelet count and acute kidney injury (AKI) or 28-day all-cause mortality induced by hemorrhagic shock (HS), and to determine the cutoff value of nadir platelet count in HS clinical practice. This retrospective study included hospitalized patients enrolled in a tertiary-care teaching hospital from January 1, 2010 to December 31, 2015. Clinical data from HS admitted to the intensive care unit (ICU) were evaluated. Nadir platelet count was defined as the lowest values in the first 48 h. Multivariate logistic regression and Cox proportional hazards regression were used to assess the correlation between nadir platelet count and AKI or 28-day all-cause mortality induced by HS, respectively; the area under receiver operating characteristic (AU-ROC) and Youde's index were used to determine the optimal cutoff value of nadir platelet count. Kaplan-Meier's method and log-rank test were assessed for the 28-day all-cause mortality in AKI and non-AKI groups. Of 1589 patients screened, 84 patients (mean age,37.1 years; 58 males) were included in the primary analysis in which 30 patients with AKI. Multiple logistic results indicated that nadir platelet count was a risk factor of AKI (OR = 0.71,95% confidence interval [CI] 0.54-0.93, P < 0.05). Cox regression analysis revealed that nadir platelet count was independent risk factors for 28-day all-cause mortality (Hazard ratios [HR]0.89,95%CI 0.76-0.99, P < 0.05). Kaplan-Meier curve showed that 28-day all-cause mortality was significantly higher in patients with AKI than non-AKI (P < 0.001).These results suggest that nadir platelet count in the first 48 h is a new biomarker for AKI and 28-day all-cause mortality induced by HS. Moreover, the risk for AKI and 28-day all-cause mortality in HS patients decreased by 29% and 11%, respectively, for every 10 × 109/L increase in platelet count. Additional studies are needed to investigate whether elevation of nadir platelet count reduces the risk in different genders.


Subject(s)
Acute Kidney Injury/blood , Acute Kidney Injury/etiology , Biomarkers , Platelet Count , Shock, Hemorrhagic/complications , Acute Kidney Injury/diagnosis , Acute Kidney Injury/mortality , Adolescent , Adult , Aged , Aged, 80 and over , Blood Transfusion , Cause of Death , Female , Humans , Intensive Care Units , Male , Middle Aged , Prognosis , Proportional Hazards Models , ROC Curve , Retrospective Studies , Risk Factors , Shock, Hemorrhagic/etiology , Shock, Hemorrhagic/mortality , Shock, Hemorrhagic/therapy , Young Adult
4.
Med Sci Monit ; 25: 9630-9636, 2019 Dec 16.
Article in English | MEDLINE | ID: mdl-31842202

ABSTRACT

BACKGROUND Preeclampsia is a severe obstetric complication affecting the health of pregnant women. The aim of this study was to determine the effect of LAMA4 gene on extravillous trophoblasts (EVTs) in the pathogenesis of preeclampsia and its possible regulatory mechanism. MATERIAL AND METHODS HTR-8/SVneo cells were transfected with small-interfering ribonucleic acid (siRNA) targeting LAMA. The LAMA4 protein level was detected via Western blotting. Moreover, the influences of LAMA4 gene on the proliferation, migration and invasion of HTR-8/SVneo cells were detected via cell counting kit-8 (CCK-8) assay and Transwell assay. We also assessed the influences of LAMA4 gene on vascular endothelial growth factor (VEGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) messenger RNA (mRNA) levels in HTR-8/SVneo cells as measured by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS The cell lines with downregulation of LAMA4 gene were successfully established by transfection. Compared with those in the normal group, the proliferation, migration, and invasion of HTR-8/SVneo cells declined, the VEGF mRNA level was reduced, and the sFlt-1 mRNA level was increased in the silencing group. CONCLUSIONS Downregulation of the LAMA4 gene inhibits the proliferation, migration, and invasion of EVT to suppress the expression of vascular factors, leading to the occurrence or development of preeclampsia. Our data provide new insights into modulation of LAMA4 expression as a potential target for therapy against preeclampsia. Further research is needed on placenta sampling from pre-eclamptic pregnancies to validate the effect of LAMA4 expression compared to control pregnancies.


Subject(s)
Laminin/genetics , Pre-Eclampsia/genetics , Pre-Eclampsia/pathology , Trophoblasts/metabolism , Cell Line , Cell Movement/genetics , Cell Proliferation/genetics , Cell Survival/genetics , Female , Gene Expression Regulation , Humans , Laminin/metabolism , Models, Biological , Pregnancy , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Small Interfering/metabolism , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor Receptor-1/genetics , Vascular Endothelial Growth Factor Receptor-1/metabolism
6.
Angew Chem Int Ed Engl ; 55(25): 7161-5, 2016 06 13.
Article in English | MEDLINE | ID: mdl-27159245

ABSTRACT

A recent technological trend in the field of electrochemical energy storage is to integrate energy storage and electrochromism functions in one smart device, which can establish efficient user-device interactions based on a friendly human-readable output. This type of newly born energy storage technology has drawn tremendous attention. However, there is still plenty of room for technological and material innovation, which would allow advancement of the research field. A prototype Al-tungsten oxide electrochromic battery with interactive color-changing behavior is reported. With the assistance of trace amount of H2 O2 , the battery exhibits a specific capacity almost seven times that for the reported electrochromic batteries, up to 429 mAh g(-1) . Fast decoloration of the reduced tungsten oxide affords a very quick charging time of only eight seconds, which possibly comes from an intricate combination of structure and valence state changes of tungsten oxide. This unique combination of features may further advance the development of smart energy storage devices with suitability for user-device interactions.

8.
Nano Lett ; 14(4): 2150-6, 2014.
Article in English | MEDLINE | ID: mdl-24593047

ABSTRACT

Supercapacitors are important energy storage technologies in fields such as fuel-efficient transport and renewable energy. State-of-the-art supercapacitors are capable of supplanting conventional batteries in real applications, and supercapacitors with novel features and functionalities have been sought for years. Herein, we report the realization of a new concept, a smart supercapacitor, which functions as a normal supercapacitor in energy storage and also communicates the level of stored energy through multiple-stage pattern indications integrated into the device. The metal-oxide W18O49 and polyaniline constitute the pattern and background, respectively. Both materials possess excellent electrochemical and electrochromic behaviors and operate in different potential windows, -0.5-0 V (W18O49) and 0-0.8 V (polyaniline). The intricate cooperation of the two materials enables the supercapacitor to work in a widened, 1.3 V window while displaying variations in color schemes depending on the level of energy storage. We believe that our success in integrating this new functionality into a supercapacitor may open the door to significant opportunities in the development of future supercapacitors with imaginative and humanization features.

9.
Sci Rep ; 3: 2263, 2013.
Article in English | MEDLINE | ID: mdl-23877331

ABSTRACT

Oxygen conversion process between O2 and H2O by means of electrochemistry or photochemistry has lately received a great deal of attention. Cobalt-phosphate (Co-Pi) catalyst is a new type of cost-effective artificial oxygen-evolving complex (OEC) with amorphous features during photosynthesis. However, can such Co-Pi OEC also act as oxygen reduction reaction (ORR) catalyst in electrochemical processes? The question remains unanswered. Here for the first time we demonstrate that Co-Pi OEC does be rather active for the ORR. Particularly, Co-Pi OEC anchoring on reduced graphite oxide (rGO) nanosheet is shown to possess dramatically improved electrocatalytic activities. Differing from the generally accepted role of rGO as an "electron reservoir", we suggest that rGO serves as "peroxide cleaner" in enhancing the electrocatalytic behaviors. The present study may bridge the gap between photochemistry and electrochemistry towards oxygen conversion.


Subject(s)
Cobalt/chemistry , Graphite/chemistry , Nanostructures/chemistry , Oxides/chemistry , Oxygen/chemistry , Phosphates/chemistry , Catalysis , Electrochemistry , Nanostructures/ultrastructure , Photochemistry , Photoelectron Spectroscopy , Water/chemistry
10.
Chem Commun (Camb) ; 49(51): 5787-9, 2013 Jun 28.
Article in English | MEDLINE | ID: mdl-23695299

ABSTRACT

Nitrogen-doped tungstic acid hydrate (N-doped H2W(1.5)O(5.5)·H2O) has been developed as a new kind of efficient "three-in-one" water treatment material. The new material shows excellent uptake capacity towards various aqueous pollutants, as well as good photocatalytic detoxification and visible-light-driven photosensitized degradation performance.

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