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1.
Opt Express ; 32(8): 13322-13330, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38859305

ABSTRACT

The multi-channel perfect vortex (PV) array based on metasurface has important applications in optical communication, particle manipulation, quantum optics, and other fields due to its ultra-thin structure and excellent wavefront control ability. However, it is very challenging to utilize a single metasurface to simultaneously achieve independent channel PV arrays at different wavelengths with low crosstalk and low structural complexity. Here, we propose and design a single rectangular structured metasurface based on TiO2, achieving a multi-channel PV beam array with dual-wavelength and dual-polarization multiplexing. Simulation and experimental results show that when two orthogonal linearly polarized beams with wavelengths of 532 nm and 633 nm are incident on the metasurface, clear PV arrays with corresponding topological charge arrangements can be obtained in different diffraction regions of the same observation plane. The metasurface proposed in this article can enhance the channel capacity of a PV beam array through wavelength-polarization-multiplexing, thus having important application potential in spatial information transmission, high-dimensional information storage, and secure information encryption.

2.
Acad Med ; 99(2): 164-168, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-37881940

ABSTRACT

PROBLEM: Within health science disciplines, power dynamics exist that can not only perpetuate harm but also foster feelings of powerlessness and disengagement. Although diversity, equity, and inclusion approaches have been prioritized by many institutions to improve student and staff recruitment, few effective structures exist to promote the retention, support, and inclusion of these individuals. APPROACH: Restorative justice circles facilitate a collaborative and personal exercise that welcomes the input of all members, thus acting as a catalyst toward broader and more deeply rooted culture changes and conflict resolution. Restorative justice circles can be applied to strengthen academic learning environments by building community and creating intentional dialog spaces to promote accountability and belonging. The Phoenix Gender-based Violence Lab is an interdisciplinary health research lab composed of diverse researchers who meet monthly for a restorative justice-inspired community-building circle and discussion. The lab members participated in community-building circles from August 2021 to August 2022 during which circle facilitators aimed to prioritize safety, trustworthiness, and transparency and provide collaboration opportunities. OUTCOMES: All 10 research team members consented to an anonymous evaluation survey to share their perspectives about incorporating this approach into lab time. Research team members expressed many benefits of circle discussions, including mitigated power dynamics (n = 5), increased lab cohesion (n = 9), improved research processes (n = 6), and enhanced honesty and accountability (n = 4). NEXT STEPS: Circle practice has shown promising results within the Phoenix Gender-based Violence Lab, indicating that other academic and medical settings should consider its potential to enhance group dynamics, foster accountability, and cultivate deeper collaboration and appreciation among group members. Further investigation of circle practice in diverse medical and academic settings is needed to fully comprehend the range of outcomes resulting from this intervention and whether they align with the fundamental principles of restorative justice.


Subject(s)
Academia , Humans , Research
3.
Clin Appl Thromb Hemost ; 29: 10760296231171603, 2023.
Article in English | MEDLINE | ID: mdl-37194267

ABSTRACT

This study developed and evaluated a tailored nomogram to predict the potential occurrence of early lower extremity deep vein thrombosis (LDVT) in patients receiving thrombolytic therapy. We performed several logistic analyses on the training cohort and created a corresponding nomogram to forecast early LDVT. The classification accuracy and the accuracy of predicted probabilities of the multiple logistic regression model were evaluated using area under the curve (AUC) and the calibration graph method. According to the multivariate logistic regression model homocysteine, previous history of hypertension and atrial fibrillation, indirect bilirubin, age, and sex was identified as independent determinants of early LDVT. The nomogram was constructed using these variables. The calibration plots showed a good agreement between the predicted and observed LDVT possibilities in the training and validation cohorts with AUCs being 0.833 (95% CI: 0.774-0.892) and 0.907 (95% CI: 0.801-1.000), respectively. Our nomogram offers clinicians a tool for predicting the individual risk of LDVT in the early stage of acute ischemic stroke in patients receiving thrombolytic therapy, which could lead to early intervention.


Subject(s)
Ischemic Stroke , Humans , Nomograms , Thrombolytic Therapy/adverse effects , Area Under Curve , Lower Extremity
4.
Chem Asian J ; 17(24): e202200929, 2022 Dec 14.
Article in English | MEDLINE | ID: mdl-36210332

ABSTRACT

Hybrid composite electrolytes incorporate polymer matrixes and garnet filler attract the focus of concern for all-solid-state batteries, which possess high ionic conductivity, superior electrochemical stability, and wide electrochemical window of ceramic electrolyte advantages, and exhibit excellent flexibility and tensile shear strength from polymer electrolyte benefits. Hence, the unique structure design of solid-state electrolytes resolves the existing defects that the use of either single garnet or polymer electrolytes implemented into battery devices. This review summarizes Li7 La3 Zr2 O12 (LLZO)/polymer solid composite electrolytes (SCEs), comprising LLZO/polymer SCEs with various structures and different ratios of LLZO fillers, LLZO/polymer with different kinds of polymers matrix and hybrid lithium-salt, and Li+ transport pathways within the LLZO/polymers SCEs interface. The purpose here is to propose the viewpoints and challenges of LLZO/polymer SCEs to promote the development of next-generation solid electrolytes.

5.
Biomed Opt Express ; 13(7): 4021-4031, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35991910

ABSTRACT

We presented a strategy for enhancing the sensitivity of terahertz glucose sensing with a hydrogel platform pre-embedded with Au nanoparticles. Physiological-level glucose solutions ranging from 0 to 0.8 mg/mL were measured and the extracted absorption coefficients can be clearly distinguished compared to traditional terahertz time domain spectroscopy performed directly on aqueous solutions. Further, Isotherm models were applied to successfully describe the relationship between the absorption coefficient and the glucose concentration (R2 = 0.9977). Finally, the origin of the sensitivity enhancement was investigated and verified to be the pH change induced by the catalysis of Au nanoparticles to glucose oxidation.

6.
Opt Express ; 30(8): 12268-12277, 2022 Apr 11.
Article in English | MEDLINE | ID: mdl-35472865

ABSTRACT

Quantitative detection of neurotransmitters in aqueous environment is crucial for the early diagnosis of many neurological disorders. Terahertz waves, as a non-contact and non-labeling tool, have demonstrated large potentials in quantitative biosensing. Although the detection of trace-amount analyte has been achieved with terahertz metamaterials in the recent decades, most studies have been focused on dried samples. Here, a hexagonal asymmetric metamaterial sensor was designed and fabricated for aqueous solution sensing with terahertz waves in the reflection geometry. An absorption enhancement of 43 was determined from the simulation. Dilute adrenaline solutions ranging from 30 µM to 0.6 mM were measured on our sensor using a commercial terahertz time-domain spectroscopy system, and the effective absorption was found to be linearly correlated with the concentration (R2 = 0.81). Furthermore, we found that as the concentration becomes higher (>0.6 mM), a non-linear relationship starts to take place, which confirmed the previous theory on the extended solvation shell that can be probed on the picosecond scale. Our sensor, without the need of high-power and stable terahertz sources, has enabled the detection of subtle absorption changes induced by the solvation dynamics.


Subject(s)
Epinephrine , Terahertz Spectroscopy , Computer Simulation , Water/chemistry
7.
Nanomaterials (Basel) ; 11(5)2021 May 01.
Article in English | MEDLINE | ID: mdl-34062796

ABSTRACT

Developing highly efficient anchoring materials to suppress sodium polysulfides (NaPSs) shuttling is vital for the practical applications of sodium sulfur (Na-S) batteries. Herein, we systematically investigated pristine graphene and metal-N4@graphene (metal = Fe, Co, and Mn) as host materials for sulfur cathode to adsorb NaPSs via first-principles theory calculations. The computing results reveal that Fe-N4@graphene is a fairly promising anchoring material, in which the formed chemical bonds of Fe-S and N-Na ensure the stable adsorption of NaPSs. Furthermore, the doped transition metal iron could not only dramatically enhance the electronic conductivity and the adsorption strength of soluble NaPSs, but also significantly lower the decomposition energies of Na2S and Na2S2 on the surface of Fe-N4@graphene, which could effectively promote the full discharge of Na-S batteries. Our research provides a deep insight into the mechanism of anchoring and electrocatalytic effect of Fe-N4@graphene in sulfur cathode, which would be beneficial for the development of high-performance Na-S batteries.

8.
Micromachines (Basel) ; 12(6)2021 May 30.
Article in English | MEDLINE | ID: mdl-34070887

ABSTRACT

Pathogenic fungi and oomycetes give rise to a significant number of animal and plant diseases. While the spread of these pathogenic microorganisms is increasing globally, emerging resistance to antifungal drugs is making associated diseases more difficult to treat. High-throughput screening (HTS) and new developments in lab-on-a-chip (LOC) platforms promise to aid the discovery of urgently required new control strategies and anti-fungal/oomycete drugs. In this review, we summarize existing HTS and emergent LOC approaches in the context of infection strategies and invasive growth exhibited by these microorganisms. To aid this, we introduce key biological aspects and review existing HTS platforms based on both conventional and LOC techniques. We then provide an in-depth discussion of more specialized LOC platforms for force measurements on hyphae and to study electro- and chemotaxis in spores, approaches which have the potential to aid the discovery of alternative drug targets on future HTS platforms. Finally, we conclude with a brief discussion of the technical developments required to improve the uptake of these platforms into the general laboratory environment.

9.
Nanomaterials (Basel) ; 10(11)2020 Oct 29.
Article in English | MEDLINE | ID: mdl-33137920

ABSTRACT

In this paper, the band-gap tunability of three monolayer semiconductors under hydrostatic pressure was intensively investigated based on first-principle simulations with a focus on monolayer antimony (Sb) as a semiconductor nanomaterial. As the benchmark study, monolayer black phosphorus (BP) and monolayer molybdenum disulfide (MoS2) were also investigated for comparison. Our calculations showed that the band-gap tunability of the monolayer Sb was much more sensitive to hydrostatic pressure than that of the monolayer BP and MoS2. Furthermore, the monolayer Sb was predicted to change from an indirect band-gap semiconductor to a conductor and to transform into a double-layer nanostructure above a critical pressure value ranging from 3 to 5 GPa. This finding opens an opportunity for nanoelectronic, flexible electronics and optoelectronic devices as well as sensors with the capabilities of deep band-gap tunability and semiconductor-to-metal transition by applying mechanical pressure.

10.
Lab Chip ; 20(22): 4141-4151, 2020 11 10.
Article in English | MEDLINE | ID: mdl-33057547

ABSTRACT

This paper describes the design, fabrication and characterisation of a novel monolithic lab-on-a-chip (LOC) platform combining the trapping and germination of individual zoospores of the oomycete Achlya bisexualis with elastomeric micropillar-based protrusive force sensing. The oomycetes are of significant interest due to their pathogenic capabilities, which can have profound ecological and economic impacts. Zoospore encystment and germination via a germ tube play a key role in their pathogenicity. Our platform enables the study of these processes at a single cell level through hydrodynamic trapping of zoospores and their individual compartmentalization via normally closed pneumatic membrane microvalves. Valve geometry was optimized and media exchange characterized during dynamic valve operations to enhance the capture-to-growth ratio. We demonstrate germination of A. bisexualis zoospores on the platform and report three distinct germination patterns. Once germinated, germ tubes grew down growth channels towards single elastomeric micropillars. Tracking of pillar movement allowed for the measurement of microNewton range protrusive forces imparted by the tips of the germ tubes. Results indicate that the forces generated by the germ tubes are smaller than those exerted by mature hyphae. Through the use of parallel traps, channels and pillars on the same device, the platform enables high-throughput screening (HTS) of zoospores and their generation of protrusive force, an essential component of their infective capability. Due to its versatility, it will also allow for the screening of naturally bioactive compounds and the development of new biocontrol strategies for oomycetes, and morphologically similar fungal infections, as an alternative to agrochemicals.


Subject(s)
Achlya , Microfluidics , Cytoskeleton , Hyphae , Lab-On-A-Chip Devices
11.
Front Chem ; 7: 591, 2019.
Article in English | MEDLINE | ID: mdl-31508412

ABSTRACT

LiNi0.5Mn1.5O4 (LNMO) is a potential cathode material for lithium-ion batteries with outstanding energy density and high voltage plateau (>4.7 V). However, the interfacial side reaction between LNMO and the liquid electrolyte seriously causes capacity fading during cycling at the high voltage. Here, p-toluenesulfonyl isocyanate (PTSI) is used as the electrolyte additive to overcome the above problem of LNMO. The results show that the specific capacity of LNMO/Li cell with 0.5 wt.% PTSI at the first cycle is effectively enhanced by 36.0 mAh/g and has better cycling performance than that without PTSI at 4.98 V. Also, a stable solid electrolyte interface (SEI) film derived from PTSI is generated on the electrode surface, which could alleviate the strike of hydrofluoric acid (HF) caused by electrolyte decomposition. These results are explained by the molecular structure of PTSI, which contains SO3. The S=O groups can delocalize the nitrogen nucleus to block the reactivity of PF5.

12.
Nanomaterials (Basel) ; 9(5)2019 May 01.
Article in English | MEDLINE | ID: mdl-31052439

ABSTRACT

Linear tunability has important applications since it can be realized by using linear control voltage and can be used conveniently without requiring nonlinear scale. In this paper, a kind of plasmonic nanostructure with a waveguide loaded with two rectangular cavities coupled by a circular cavity is proposed to produce four Fano resonance modes. The transfer matrix theory is employed to analyze the coupled-waveguide-cavity system. By analyzing the property of each single cavity, it reveals that the Fano resonances are originated from the coupling effect of the narrow modes in the metal-core circular cavity and the broad modes in the rectangular cavities. Owing to the interference of different modes, Fano peaks have different sensitivities on the cavity parameters, which can provide important guidance for designing Fano-resonance structures. Furthermore, adjusting the orientation angle of the metal core in the circular cavity can easily tune the line profile of Fano resonance modes in the structure. Especially, the figure of merit (FoM) increases linearly with the orientation angle and has a maximum of 8056. The proposed plasmonic system has the advantage of high transmission, ultracompact configuration, and easy integration, which can be applied in biochemical detecting or sensing, ultra-fast switching, slow-light technologies, and so on.

13.
Nanoscale Res Lett ; 14(1): 32, 2019 Jan 22.
Article in English | MEDLINE | ID: mdl-30671732

ABSTRACT

A graphene-loaded metamaterial absorber is investigated in the mid-infrared region. The light-graphene interaction is greatly enhanced by virtue of the coupled resonance through a cross-shaped slot. The absorption peaks show a significant blueshift with increasing Fermi level, enabling a wide range of tunability for the absorber. A simple circuit model well explains and predicts this modulation behavior. Our proposal may find applications in a variety of areas such as switching, sensing, modulating, and biochemical detecting.

14.
Front Chem ; 7: 867, 2019.
Article in English | MEDLINE | ID: mdl-32010662

ABSTRACT

In this study, silicon/carbon composite nanofibers (Si@CNFs) were prepared as electrode materials for lithium-ion batteries via a simple electrospinning method and then subjected to heat treatment. The morphology and structure of these materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results show that the structure provides good electrical conductivity and affords sufficient space to accommodate volume expansion during charging/discharging. Furtherly, electrochemical performance tests show that the optimized Si@CNFs have an initial reversible capacity of 1,820 mAh g-1 at a current density of 400 mA g-1 and capacity retention of 80.7% after 100 cycles at a current density of 800 mA g-1. Interestingly, the optimized Si@CNFs have a superior capacity of 1,000 mAh g-1 (400 mA g-1) than others, which is attributed to the carbon substrate nanofiber being able to accommodate the volume expansion of Si. The SEI resistance generated by the Si@CNFs samples is smaller than that of the Si nanoparticles, which confirms that SEI film generated from the Si@CNFs is much thinner than that from the Si nanoparticles. In addition, the connected carbon substrate nanofiber can form a fiber network to enhance the electronic conductivity.

15.
Appl Opt ; 57(12): 2962-2966, 2018 Apr 20.
Article in English | MEDLINE | ID: mdl-29714330

ABSTRACT

This work shrinks down the size of Ge-on-Si photodetectors to reduce the dark current and maintain the optical responsivity by surrounding photonic crystals. Numerical simulation shows that the employment of photonic crystal in the Si slab effectively prohibits the radiation modes from those guided outgoing waves and facilitates light cyclic absorption in the epitaxial Ge region. A photodetector with a 5 µm long Ge absorption region is demonstrated with a dark current of 150 nA (1 µA up to 70°C), a 3 dB bandwidth of 17 GHz, and a responsivity of 0.75 A/W.

16.
Sensors (Basel) ; 18(4)2018 Mar 29.
Article in English | MEDLINE | ID: mdl-29596341

ABSTRACT

In this paper, a type of tunable plasmonic refractive index nanosensor based on Fano resonance is proposed and investigated. The sensor comprises a metal-insulator-metal (MIM) nanocavity with a center-deviated metal core and two side-coupled waveguides. By carefully adjusting the deviation angle and distance of the metal core in the cavity, Fano resonances can be obtained and modulated. The Fano resonances can be considered as results induced by the symmetry-breaking or geometric effect that affects the field distribution intensity at the coupling region between the right waveguide and the cavity. Such a field-distribution pattern change can be regarded as being caused by the interference between the waveguide modes and the cavity modes. The investigations demonstrate that the spectral positions and modulation depths of Fano resonances are highly sensitive to the deviation parameters. Furthermore, the figure of merit (FOM) value is calculated for different deviation angle. The result shows that this kind of tunable sensor has compact structure, high transmission, sharp Fano lineshape, and high sensitivity to the change in background refractive index. This work provides an effective method for flexibly tuning Fano resonance, which has wide applications in designing on-chip plasmonic nanosensors or other relevant devices, such as information modulators, optical filters, and ultra-fast switches.

17.
Kaohsiung J Med Sci ; 33(11): 543-549, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29050671

ABSTRACT

Gambogic acid (GA) has been shown to inhibit cancer cell proliferation, induce apoptosis, and enhance reactive oxygen species accumulation. However, whether GA could improve multidrug resistance through modulating autophagy has never been explored. We demonstrated that the combination of GA and cisplatin (CDDP) resulted in a stronger growth inhibition effect on A549 and NCI-H460 cells using the MTT assay. Furthermore, treatment with GA significantly increased autophagy in these cells. More importantly, GA-induced cell death could be largely abolished by 3-methyladenine (3-MA) or chloroquine (CQ) treatment, suggesting that GA-induced cell death was dependent on autophagy. Western blot analysis showed that GA treatment suppressed the activation of Akt, mTOR, and S6. In addition, using a GA and rapamycin combination induced more cell death compared to either GA or rapamycin alone. In summary, GA may have utility as an adjunct therapy for non-small cell lung cancer (NSCLC) patients through autophagy-dependent cell death, even when cancer cells have developed resistance to apoptosis.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Autophagy/drug effects , Garcinia/chemistry , Gene Expression Regulation, Neoplastic , Xanthones/pharmacology , A549 Cells , Adenine/analogs & derivatives , Adenine/pharmacology , Antineoplastic Agents, Phytogenic/isolation & purification , Autophagy/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Chloroquine/pharmacology , Cisplatin/pharmacology , Drug Combinations , Drug Synergism , Humans , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Plant Extracts/chemistry , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Ribosomal Protein S6/antagonists & inhibitors , Ribosomal Protein S6/genetics , Ribosomal Protein S6/metabolism , Signal Transduction , Sirolimus/pharmacology , TOR Serine-Threonine Kinases/antagonists & inhibitors , TOR Serine-Threonine Kinases/genetics , TOR Serine-Threonine Kinases/metabolism , Xanthones/isolation & purification
18.
Lab Chip ; 17(21): 3643-3653, 2017 10 25.
Article in English | MEDLINE | ID: mdl-28959802

ABSTRACT

Oomycetes and fungi are microorganisms whose pathogenic (invasive) growth can cause diseases that are responsible for significant ecological and economic losses. Such growth requires the generation of a protrusive force, the magnitude and direction of which involves a balance between turgor pressure and localised yielding of the cell wall and the cytoskeleton. To study invasive growth in individual hyphae we have developed a lab-on-a-chip platform with integrated force-sensors based on elastomeric polydimethylsiloxane (PDMS) micro-pillars. With this platform we are able to measure protrusive force (both magnitude and direction) and hyphal morphology. To show the usefulness of the platform, the oomycete Achlya bisexualis was inoculated and grown on a chip. Growth of individual hyphae into a micro-pillar revealed a maximum total force of 10 µN at the hyphal tip. The chips had no discernible effect on hyphal growth rates, but hyphae were slightly thinner in the channels on the chips compared to those on agar plates. When the hyphae contacted the pillars tip extension decreased while tip width increased. A. bisexualis hyphae were observed to reorient their growth direction if they were not able to bend and effectively grow over the pillars. Estimates of the pressure exerted on a pillar were 0.09 MPa, which given earlier measures of turgor of 0.65 MPa would indicate low compliance of the cell wall. The platform is adaptable to numerous cells and organisms that exhibit tip-growth. It provides a useful tool to begin to unravel the molecular mechanisms that underlie the generation of a protrusive force.


Subject(s)
Elastomers/chemistry , Hyphae/physiology , Lab-On-A-Chip Devices , Achlya/physiology , Biomechanical Phenomena/physiology , Cell Wall/physiology , Dimethylpolysiloxanes/chemistry , Elasticity , Equipment Design , Fungi/physiology , Pressure
19.
Nanoscale Res Lett ; 12(1): 390, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28591980

ABSTRACT

Titanium dioxide (TiO2) nanoparticles were modified onto fluorine-doped tin oxide (FTO) via dip-coating technique with different nanoparticle sizes, lifting speeds, precursor concentrations, and dipping numbers. Electrodeposition-based electrochromic device with reversible three-state optical transformation (transparent, mirror, and black) was fabricated subsequently by sandwiching a suitable amount of gel electrolyte between modified FTO electrode and flat FTO electrode. Correlation between dip-coating process engineering, morphological features of TiO2 thin films, i.e., thickness and roughness, as well as performance of electrochromic devices, i.e., optical contrast, switching time, and cycling stability, were investigated. The modified device exhibits high optical contrast of 57%, the short coloration/bleaching switching time of 6 and 20 s, and excellent cycling stability after 1500 cycles of only 27% decrement rate by adjusting dip-coating processes engineering. The results in this study will provide valuable guidance for rational design of the electrochromic device with satisfactory performance.

20.
Inorg Chem ; 56(3): 1713-1721, 2017 Feb 06.
Article in English | MEDLINE | ID: mdl-28094932

ABSTRACT

A series of five unique d-f heteronuclear luminescent metal-organic frameworks (MOFs) in an entangled polyrotaxane array and the light-harvesting block homonuclear zinc compound have been isolated successfully and characterized. The series of isostructural polymers feature 3,4-connected (4.82)(4.83.92)(6.8.9)2(6.92)(83) topology and high stability, exhibiting diverse void spaces. By taking advantage of the isostructural MOFs 2 and 3, the intensities of red and green emissions can be modulated by adjusting the ratios of EuIII and TbIII ions correspondingly, and white-light emission can be generated by a combination of different doped TbIII and EuIII concentrations. The Tb-Zn-based framework {[Tb3Zn6(bipy2)2(Hmimda)7 (H2O)3]·5H2O}n (3; H3mimda = 2-methyl-1-H-imidazole-4,5-dicarboxylic acid and bipy = 4,4'-bipyridine) can detect trace MgII ion with relatively high sensitivity and selectivity. Dehydrated MOF 3a shows a remarkable emission quenching effect through the introduction of I2 solids. Further investigation indicates that it exhibits turn on/off switchable properties for small solvent molecules or heavy-metal ions. Steady/transient-state near-IR luminescence properties for MOFs 1, 4, and 5 were investigated under visible-light excitation.

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