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Background: There are limited studies designed by matching related factors to compare clinical outcomes and return to sport (RTS) between patients undergoing revision anterior cruciate ligament reconstruction (R-ACLR) and primary ACLR (P-ACLR). Purpose: (1) To compare the outcomes between R-ACLR and P-ACLR in a matched-pair analysis with 3- to 5-year follow-up and (2) to evaluate patient-reported factors for not returning to preinjury-level sport. Study Design: Cohort study; Level of evidence, 4. Methods: Patients who underwent R-ACLR between September 2016 and November 2018 were propensity matched by age, sex, body mass index, passive anterior tibial subluxation, and generalized hypermobility in a 1:1 ratio to patients who underwent P-ACLR during the same period. By combining in person follow-up at 2 years postoperatively and telemedicine interview at the final follow-up (January 2022), knee stability and clinical scores were compared, including International Knee Documentation Committee (IKDC), Lysholm, and Tegner. Status of RTS was requested, specifically whether the patient returned to preinjury level of sport. Patient-reported reasons for not returning were analyzed. Results: There were 63 matched pairs in the present study. Knee stability was similar in terms of KT-2000 arthrometer, Lachman test, and pivot-shift test results between the groups at 2 years of follow-up. At the final follow-up, no significant difference was found between groups for postoperative clinical scores (IKDC, Tegner, and Lysholm) ( P > .05). There was a significant difference in total RTS: 53 (84.1%) in the P-ACLR cohort and 41 (65.1%) in the R-ACLR cohort ( P = .014). No significant difference was shown in terms of RTS at the same level: 35 (55.6%) in P-ACLR and 31 (49.2%) in R-ACLR ( P = .476). Significantly more patients showed fear of reinjury: 26 of 32 (81.3%) in the R-ACLR group as compared with 15 of 28 (53.5%) in the P-ACLR group ( P < .021). Conclusion: R-ACLR resulted in similar clinical scores (IKDC, Tegner, and Lysholm) but significantly lower RTS versus P-ACLR at 3 to 5 years of follow-up. Fear of reinjury was the most common factor that caused sport changes in patients with R-ACLR.

Osteochondral injury is a common and frequent orthopedic disease that can lead to more serious degenerative joint disease. Tissue engineering is a promising modality for osteochondral repair, but the implanted scaffolds are often immunogenic and can induce unwanted foreign body reaction (FBR). Here, we prepare a polypept(o)ide-based PAA-RGD hydrogel using a novel thiol/thioester dual-functionalized hyperbranched polypeptide P(EG

Obstructive sleep apnea syndrome (OSAS) has mostly been examined using in-laboratory polysomnography (Lab-PSG), which may overestimate severity. This study compared sleep parameters in different environments and investigated the association between the plasma levels of neurochemical biomarkers and sleep parameters.Thirty Taiwanese participants underwent Lab-PSG while wearing a single-lead electrocardiogram patch. Participants' blood samples were obtained in the morning immediately after the recording. Participants wore the patch for the subsequent three nights at home. Sleep disorder indices were calculated, including the apnea-hypopnea index (AHI), chest effort index, and cyclic variation of heart rate index (CVHRI). The 23 eligible participants' derived data were divided into the normal-to-moderate (N-M) group and the severe group according to American Association of Sleep Medicine (AASM) guidelines (Lab-PSG) and the recommendations of a previous study (Rooti Rx). Spearman's correlation was used to examine the correlations between sleep parameters and neurochemical biomarker levels.The mean T-Tau protein level was positively correlated with the home-based CVHRI (r = 0.53, p 0.05), whereas no significant correlation was noted between hospital-based CVHRI and the mean T-tau protein level (r = 0.25, p = 0.25). The home-based data revealed that the mean T-Tau protein level in the severe group was significantly higher than that in the N-M group (severe group: 24.75 ± 6.16 pg/mL, N-M group: 19.65 ± 3.90 pg/mL; p 0.05). Furthermore, the mean in-hospital CVHRI was higher than the mean at-home values (12.16 ± 13.66 events/h).Severe OSAS patients classified by home-based CVHRI demonstrated the higher T-Tau protein level, and CVHRI varied in different sleep environments.

The meniscus is a fibrocartilaginous tissue of the knee joint that plays an important role in load transmission, shock absorption, joint stability maintenance, and contact stress reduction. Mild meniscal injuries can be treated with simple sutures, whereas severe injuries inevitably require meniscectomy. Meniscectomy destroys the mechanical microenvironment of the knee joint, leading to cartilage degeneration and osteoarthritis. Tissue engineering techniques, as a strategy with diverse sources and customizable and adjustable mechanical and biological properties, have emerged as promising approaches for the treatment of meniscal injuries and are represented by 3D printing. Notably, the heterogeneity of the meniscus, including its anatomical structure, cell phenotype, extracellular matrix, and biomechanical properties, is crucial for its normal function. Therefore, the construction of heterogeneous tissue-engineered menisci (TEM) has become a research hotspot in this field. In this review, we systematically summarize the heterogeneity of menisci and 3D-printed strategies for tissue-engineered anisotropic menisci. The manufacturing techniques, biomaterial combinations, surface functionalization, growth factors, and bioreactors related to 3D-printed strategies are introduced and a promising direction for the future research is proposed.

ObjectiveReliable electrophysiological indicators are urgently needed in the precise evaluation of Parkinson’s disease (PD). It is still elusive whether oculomotor performance is impaired or has clinical value in early PD. This study aims to explore oculomotor performance in newly diagnosed, drug-naïve PD and its correlation with clinical phenotype.MethodsSeventy-five patients with de novo PD, 75 patients with essential tremor (ET), and 46 gender-and age-matched healthy controls (HCs) were included in this cross-sectional study. All subjects underwent oculomotor test via videonystagmography. Visually guided saccade latency, saccadic accuracy and gain in smooth pursuit eye movement (SPEM) at three frequencies of the horizontal axis were compared among the three groups. Patients with PD also received detailed motor and non-motor evaluation by serial scales. The association between key oculomotor parameters and clinical phenotypes were explored in PD patients.ResultsBoth de novo PD and ET patients showed prolonged saccadic latency and decreased saccadic accuracy relative to HCs. SPEM gain in PD was uniformly reduced at each frequency. SPEM gain at 0.4 Hz was also decreased in ET compared with HCs. However, there was no significant difference of oculomotor parameters between de novo PD and ET patients. Furthermore, prolonged saccadic latency was correlated with long disease duration, whereas decreased SPEM gain was associated with severe motor symptoms in de novo PD patients.ConclusionOcular movements are impaired in de novo, drug naïve PD patients; these changes could be indicators for disease progression in PD.

Cartilage damage is a common injury. Currently, tissue engineering scaffolds with composite seed cells have emerged as a promising approach for cartilage repair. Polyethylene glycol (PEG) hydrogels are attractive tissue engineering scaffold materials as they have high water absorption capacity as well as nontoxic and nutrient transport properties. However, PEG is fundamentally bio-inert and lacks intrinsic cell adhesion capability, which is critical for the maintenance of cell function. Cell adhesion peptides are usually added to improve the cell adhesion capability of PEG-based hydrogels. The suitable cell adhesion peptide can not only improve cell adhesion capability, but also promote chondrogenesis and regulate the immune microenvironment. To improve the interactions between cells and PEG hydrogels, we designed cysteine-arginine-glycine-aspartic acid (CRGD), a cell adhesion peptide covalently cross-linked with PEG hydrogels by a Michael addition reaction, and explored the tissue-engineering hydrogels with immunomodulatory effects and promoted chondrogenic differentiation of mesenchymal stem cells (MSCs). The results indicated that CRGD improved the interaction between peripheral blood mesenchymal stem cells (PBMSCs) and PEG hydrogels. PEG hydrogels modified with 1 mM CRGD had the optimal capacity to promote chondrogenic differentiation, and CRGD could induce macrophage polarization towards the M2 phenotype to promote tissue regeneration and repair. PEG-CRGD hydrogels combined with PBMSCs have the potential to be suitable scaffolds for cartilage tissue engineering.

The effectiveness of existing tissue-engineering cartilage (TEC) is known to be hampered by weak integration of biocompatibility, biodegradation, mechanical strength, and microenvironment supplies. The strategy of hydrogel-based TEC holds considerable promise in circumventing these problems. Herein, a non-toxic, biodegradable, and mechanically optimized double-network (DN) hydrogel consisting of polyethylene glycol (PEG) and kartogenin (KGN)-conjugated chitosan (CHI) is constructed using a simple soaking strategy. This PEG-CHI-KGN DN hydrogel possesses favorable architectures, suitable mechanics, remarkable cellular affinity, and sustained KGN release, which can facilitate the cartilage-specific genes expression and extracellular matrix secretion of peripheral blood-derived mesenchymal stem cells (PB-MSCs). Notably, after tracing the transplanted cells by detecting the rabbit sex-determining region Y-linked gene sequence, the allogeneic PB-MSCs are found to survive for even 3 months in the regenerated cartilage. Here, the long-term release of KGN is able to efficiently and persistently activate multiple genes and signaling pathways to promote the chondrogenesis, chondrocyte differentiation, and survival of PB-MSCs. Thus, the regenerated tissues exhibit well-matched histomorphology and biomechanical performance such as native cartilage. Consequently, it is believed this innovative work can expand the choice for developing the next generation of orthopedic implants in the loadbearing region of a living body.

Reliable electrophysiological indicators are urgently needed in the precise evaluation of Parkinson's disease (PD). It is still elusive whether oculomotor performance is impaired or has clinical value in early PD. This study aims to explore oculomotor performance in newly diagnosed, drug-naïve PD and its correlation with clinical phenotype.Seventy-five patients withBothOcular movements are impaired in

In this article, a novel miniature dual-band rat-race coupler design is proposed. The proposed dual-band rat-race coupler employs differential bridged-T coils (DBTCs) as building blocks such that a very compact circuit size and a dual-band response can be achieved at the same time. Especially, through the proposed dual-band design of DBTC, arbitrary power division ratios over the two operating bands can also be realized. Explicit design equations of the proposed dual-band rat-race coupler are presented, and practical limitations on the achievable frequency ratio, power division ratio, and bandwidth are thoroughly investigated. As design examples, two 2.45-/5.5-GHz dual-band rat-race couplers with 0-/0- and 3-/0-dB power division ratios for the two bands are implemented in a silicon-based integrated passive device process. Very compact circuit sizes of less than 4.4 mm $\times \,\, 3.1$ mm as well as good measured performance are achieved. To the best of our knowledge, these are the smallest dual-band rat-race couplers ever reported.

The kinetic behavior of vapor adsorption on a solid surface in an isobaric-isothermal system is investigated by means of molecular dynamics simulations combined with theoretical studies through a statistical rate theory approach. The molecular insights into the formation and evolution of clusters in the adsorbate are presented. Results show that the argon vapor is adsorbed on the silicon surface as different types of clusters. In the initial stage of adsorption, the empty adsorption sites on the surface decrease, and the adsorbed single-molecule-cluster grows rapidly and dominates the interface. The increasing rate of the adsorbed cluster and the declining rate of the empty adsorption site are dependent on the pressure ratio. For a large pressure ratio, the single-molecule-clusters are aggregated to incubate large clusters, and the fraction of a single-molecule-cluster is decreased with time. When the adsorption isotherm is determined, the chemical potential of the adsorbed cluster is expressed from the zeta isotherm model. Then the adsorption kinetics are analyzed through the statistical rate theory. The molecular exchange rate and the instantaneous driving force are calculated. The higher pressure ratio induces the larger chemical potential difference and accelerates the net adsorption rate. The adsorption kinetics derived from MD simulations are in close agreement with the theoretical analysis of the statistical rate theory.

The effect of Rayleigh number and nanoparticle concentration on the flow dynamics and natural convection in three-dimensional large- and moderate-gap annuli is analyzed in detail in this work. A nanofluid is applied as the working fluid, with typical nanoparticle concentration ranging from zero to nine percent. The results indicate that the flow strength and deformation of isotherms becomes less intensive with an increase in the nanoparticle concentration for both large- and moderate-gap annuli. There exists a core region in the large-gap annulus, where the flow is two-dimensional and the value of the local Nusselt number is almost uniform in the axial direction. The core region exists between two secondary rolls, which are adjacent to the primary end rolls. The secondary flow decreases in size and finally disappears with an increase in the nanoparticle concentration. For the moderate-gap annulus, the space between the two end walls near the top portion is filled by multiple rolls, and an increase in the nanoparticle concentration gradually reduces the number of the rolls. The locations of the descending and ascending rolls relate to the maximum peaks of the Nusselt number on the inner and outer cylinders, respectively. The heat transfer enhancement only occurs at low nanoparticle concentrations ( φ 105) for a large-gap annulus. Otherwise, in general, a deterioration in heat transfer is observed when the nanoparticle concentration increases from 1 to 9% for both large- and moderate-gap annuli.

This paper presents a series of numerical simulations on the effect of heat dissipation on the thermocapillary convection of a low Prandtl number (Pr = 0.011) fluid in an annular pool heated from its inner cylinder. The radius ratio and the aspect ratio of the annular pool set as η = 0.5 and e = 0.1, respectively. The results show that with the increase of Biot number, the isotherms of the two-dimensional basic flow are seriously compressed near the hot inner cylinder and the thermocapillary flow pattern will be impaired. With the increase of Marangoni number, the thermocapillary convection first evolves from the basic flow to a three-dimensional stationary flow with longitudinal stationary stripes on the free surface, and then to a three-dimensional oscillatory flow featured with the combination of stationary stripes and azimuthal waves, which is caused by the mutual effect of the radial convection, azimuthal local flow and heat dissipation. After the flow destabilization, the amplitude of temperature fluctuation increases and the wave number decreases with the increase of Marangoni number when the free surface is adiabatic. Furthermore, the temperature fluctuation pattern is changed due to the surface heat dissipation. In addition, with the increase of Biot number, the wave number almost keeps constant when Marangoni number is small, but it increases significantly at a large Marangoni number.

In this randomized retrospective study, 2 different endoscopic approaches were used to treat intractable plantar fasciitis with the aim to reduce complications and improve therapeutic effects. The lateral double incisions group included 23 feet in 22 patients, and the medial and lateral incisions group included 21 feet in 19 patients. Both groups were treated with endoscopy through the suprafascial approach. Patients were evaluated using the American Orthopaedic Foot and Ankle Society ankle-hindfoot scale (AOFAS-AHS) and visual analog scale (VAS) preoperatively and 3, 6, 12, and 24 months postoperatively. At the final follow-up, the Roles-Maudsley (R-M) score was used to determine patient satisfaction. The AOFAS-AHS scores of the lateral double incisions group were 54.54 ± 7.02 preoperatively and 97.71 ± 3.67 postoperatively. Similarly, AOFAS-AHS scores in the medial and lateral incisions group were 55.52 ± 6.41 preoperatively and 96.64 ± 3.18 postoperatively. There was no significant difference in AOFAS-AHS scores between groups before and after surgery. The time to full weightbearing after surgery and the time to return to full athletic activities in the 2 groups showed no significant difference. The postoperative VAS scores were significantly lower than the preoperative values for both groups. However, no differences were noted in VAS scores or R-M scores postoperatively between the 2 groups. In the medial and lateral incisions group, 3 cases of injury of the first branch of the lateral plantar nerve occurred postoperatively. In conclusion, both endoscopic approaches are effective in the treatment of intractable plantar fasciitis. The lateral double incisions approach showed a lower incidence of nerve injury.

Little has been known about the role of long non-coding RNA (lncRNA) involves in change of aged meniscus. Microarray analyses were performed to identify lncRNAs and mRNAs expression profiles of meniscus in young and aging adults and apple bioinformatics methods to analyse their potential roles. The differentially expressed (DE) lncRNAs and mRNAs were confirmed by qRT-PCR. A total of 1608 DE lncRNAs and 1809 DE mRNAs were identified. Functional and pathway enrichment analyses of all DE mRNAs showed that DE mRNAs were mainly involved in the TGF-beta, Wnt, Hippo, PI3K-Akt signaling pathway. The expressions of TNFRSF11B and BMP2 were significantly upregulated in aging group. LASSO logistic regression analysis of the DE lncRNAs revealed four lncRNAs (AC124312.5, HCG11, POC1B-AS1, and AP001011.1) that were associated with meniscus degradation. CNC analysis demonstrated that AP001011 inhibited the expression of TNFRSF11B and AC1243125 upregulated the expression of TNFRSF11B. CeRNA analysis suggested that POC1B-AS1 regulates the expression of BMP2 by sponging miR 130a-3p, miR136-5p, miR 18a-3p, and miR 608. Furthermore, subcellular localization and m6A modification sites prediction analysis of these four lncRNAs was performed. These data lay a foundation for extensive studies on the role of lncRNAs in change of aged meniscus.

(a) Objective: Obstructive sleep apnea syndrome (OSAS) is typically diagnosed through polysomnography (PSG). However, PSG incurs high medical costs. This study developed new models for screening the risk of moderate-to-severe OSAS (apnea-hypopnea index, AHI ≥15) and severe OSAS (AHI ≥30) in various age groups and sexes by using anthropometric features in the Taiwan population.(b) Participants: Data were derived from 10,391 northern Taiwan patients who underwent PSG.(c) Methods: Patients' characteristics - namely age, sex, body mass index (BMI), neck circumference, and waist circumference - was obtained. To develop an age- and sex-independent model, various approaches - namely logistic regression, k-nearest neighbor, naive Bayes, random forest (RF), and support vector machine - were trained for four groups based on sex and age (men or women; aged50 or ≥50 years). Dataset was separated independently (training:70%; validation: 10%; testing: 20%) and Cross-validated grid search was applied for model optimization. Models demonstrating the highest overall accuracy in validation outcomes for the four groups were used to predict the testing dataset.(d) Results: The RF models showed the highest overall accuracy. BMI was the most influential parameter in both types of OSAS severity screening models.(e) Conclusion: The established models can be applied to screen OSAS risk in the Taiwan population and those with similar craniofacial features.

Enhancing phagocytosis can facilitate the removal of inflammatory molecules, limit the toxicity of dead cells and debris, and promote recovery after brain injury. In this study, we aimed to explore the role of bexarotene (Bex), a retinoid X receptor (RXR) agonist, in promoting astrocyte phagocytosis and neurobehavioral recovery after subarachnoid hemorrhage (SAH).Mice SAH model was induced by pre-chiasmatic injection of blood. Modified Garcia score, novel object recognition, rotarod test, and Morris water maze were performed to assess neurological function. Immunofluorescence and electron microscopy were used to evaluate astrocyte phagocytosis in vivo. In addition， ABCA1/MEGF10GULP1, the primary astrocyte phagocytosis pathway, were stimulated by Bex or suppressed by HX531 (a RXR antagonist) to evaluate their impacts on astrocyte phagocytosis and neurological recovery.Astrocytes phagocytosis of blood components were observed in mice after SAH induction, which is further increased by Bex treatment. Bex dramatically attenuated neuroinflammation, reduced brain edema, improved early neurological performance and promoted neurocognitive recovery. Meanwhile, Bex decreased neurotoxic reactive astrocytes and preserved neurogenesis after SAH. Bex increased the expression of astrocyte phagocytosis-related proteins ABCA1, MEGF10, and GULP1. Bex also increased the lysosomal processing of engulfed blood components in astrocytes. Moreover, Bex significantly promoted astrocytes to phagocytize debris in vitro by increasing the expression of ABCA1, MEGF10 and GULP1, while HX531 inhibited astrocyte phagocytosis and decreased these protein levels.Bex enhanced astrocyte phagocytosis through the ABCA1-mediated pathways, and promoted neurobehavior recovery in mice after SAH induction.

Over centuries, several advances have been made in osteochondral (OC) tissue engineering to regenerate more biomimetic tissue. As an essential component of tissue engineering, scaffolds provide structural and functional support for cell growth and differentiation. Numerous scaffold types, such as porous, hydrogel, fibrous, microsphere, metal, composite and decellularized matrix, have been reported and evaluated for OC tissue regeneration in vitro and in vivo, with respective advantages and disadvantages. Unfortunately, due to the inherent complexity of organizational structure and the objective limitations of manufacturing technologies and biomaterials, we have not yet achieved stable and satisfactory effects of OC defects repair. In this review, we summarize the complicated gradients of natural OC tissue and then discuss various osteochondral tissue engineering strategies, focusing on scaffold design with abundant cell resources, material types, fabrication techniques and functional properties.

In this paper, a set of direct numerical simulations on the thermocapillary flow of 2cSt silicone oil with Prandtl number of 28.01 in annular pools heated from inner cylinder were carried out. The critical Marangoni number of flow destabilization was determined, and the flow pattern evolution with Marangoni number was revealed when the aspect ratios of the annular pools were 0.375 and 0.75. It was found that the axisymmetric steady flow will transit into different types of oscillatory flows. The critical Marangoni number of flow destabilization depends on types of flow instability. At a small aspect ratio, the flow transits to the oscillatory concentric ring pattern firstly, then into the combination of the oscillatory concentric ring pattern and azimuthal non-uniform temperature fluctuation, and eventually into rotating wave, while it transits directly into the rotating wave at a large aspect ratio. With the increase of Marangoni number, the oscillation frequency of the oscillatory flow increases, and the wave number is almost unchanged. However, when the oscillatory flow pattern transition happens, there is always an abrupt drop of the oscillation frequency.

This paper presented a set of direct numerical simulations on the thermocapillary flow instability of moderate-Prandtl number fluids in annular pools heated from inner cylinder. The emphasis is on the aspect ratio dependence of the critical Marangoni number of flow destabilization and the formation mechanism of the different flow patterns. It was found that the two-dimensional axisymmetric steady flow will bifurcate into three types of oscillatory flows, including the oscillatory concentric rings, the alternating straight spoke and the rotating wave patterns. The bifurcation process depends mainly on the aspect ratio of the annular pool when the radius ratio is fixed. With the increase of the aspect ratio, the first instability flow pattern is oscillatory concentric rings and the corresponding critical Marangoni number and the oscillatory frequency decrease first, and then increase slightly. When the flow pattern transits to the alternating straight spoke pattern at the aspect ratio of 0.415, there are an abrupt increase of the critical Marangoni number and a sudden decrease of the oscillatory frequency. Furthermore, when the rotating wave pattern appears, the critical Marangoni number decreases gradually, but the corresponding oscillatory frequency has only a slight decrease.

Osteoarthritis (OA) is a musculoskeletal disorder disease affecting about 500 million people worldwide and mesenchymal sem cells (MSCs) therapy has been demonstrated as a potential strategy to treat OA. However, the shear forces during direct injection and the harsher shear condition of OA environments would lead to significant cell damage and inhibit the therapeutic efficacy. Herein, DNA supramolecular hydrogel has been applied as delivering material for MSCs to treat severe OA model, which perform extraordinary protection in MSCs against the shear force both in vitro and in vivo. It is demonstrated that the DNA supramolecular hydrogel can promote formation of quality cartilage, reduce osteophyte, and normalize subchondral bone under the high friction condition of OA, whose molecular mechanisms underlying therapeutic effects are also investigated. It can be anticipated that DNA supramolecular hydrogel would be a promising cell delivery system for multiple potential MSCs therapy.

In this study, three-dimensional numerical simulations were established for a honeycomb ceramic conduit, and the effects of the inlet methane volume fraction, inlet velocity, and the conduit length on the gas temperature and flow resistance in the conduit were investigated. The simulation results indicate that the mean gas temperature first rises rapidly and then slowly, with an increasing inlet methane volume fraction. The mean gas temperature increases slightly with an increasing inlet velocity, and first increases and then decreases with an increasing conduit length. As the inlet methane volume fraction increases, the conduit pressure loss increases, but the increase rate gradually slows down. The conduit pressure loss increases approximately linearly with an increasing inlet velocity and conduit length. A prediction model for the pressure loss in the conduit was obtained by a theoretical analysis. The theoretical results agree well with the simulation results, and the deviations between the theoretical and simulation results were in the range of 3.7% to 12.3%. When the mean gas temperature in the conduit was less than 1000 K, the deviations were less than 6.5%.

In order to understand effect of surface evaporation on thermocapillary-buoyancy convection, a series of experiments on thermocapillary-buoyancy convection in a shallow annular pool with different surface evaporation rates have been conducted. The annular pool is subjected to a radial temperature gradient, and the inner and outer radii are respectively 20 mm and 40 mm. The 0.65 cSt silicone oil has been selected as the working fluid for its relatively strong volatility. Results show that the surface evaporation rate depends mainly on Marangoni number and the average temperature of the working fluid. At a weak evaporation, the critical Marangoni number increases with the increase of the surface evaporation rate and the liquid pool depth, i.e. the surface evaporation and buoyancy effects can suppress the flow destabilization. When the three-dimensional flow appears, the temperature fluctuation from the hydrothermal waves and the free surface fluctuation of the liquid layer are regular and coincident. However, in the case of the rapid evaporation, the vapor recoil can directly trigger the flow instability. Furthermore, the temperature fluctuation is weakened significantly, and the surface fluctuation of the liquid layer become irregular due to the vapor recoil effect.

In order to understand the effect of surface heat dissipation on thermocapillary convection of moderate Prandtl number fluid in an annular shallow pool, we performed a series of three-dimensional numerical simulations by using the finite volume method. An annular shallow pool is full of 0.65cSt silicone oil with Prandtl number of 6.7. The radius ratio and the aspect ratio of the pool are respectively fixed at 0.5 and 0.1. Surface heat dissipation Biot number is varied from 0 to 50. Results indicate that the critical Marangoni number of flow destabilization mainly depends on the coupling effect of the thermocapillary force and surface heat dissipation on the free surface, which decreases first, and then increases gradually. When Biot number is small, the steady axisymmetric flow after the flow destabilization will bifurcate to the hydrothermal wave. With the increase of Marangoni number, the flow pattern evolution at a small Biot number is similar to that of an adiabatic free surface, and the fundamental oscillatory frequency increases gradually. With the increase of Biot number, the radial roll cells near the outer cylindrical wall gradually extend to the inner wall, and eventually occupy the whole liquid pool. When Biot number is large, the flow pattern after the flow destabilization is a radial rolling cell pattern with alternating azimuthal direction. Then it gradually evolves into azimuthal waves, and the fundamental oscillatory frequency has a slight decrease.

In order to understand the effect of capillary ratio on the thermal-solutal capillary convection in an annular pool subjected to simultaneous radial thermal and solutal gradients, a series of three-dimensional direct numerical simulation have been conducted. The working fluid was the toluene/n-hexane mixture fluid with the Prandtl number of 5.54 and the Schmidt number of 142.8. The capillary ratio Rσ varied from −5 to 0. Results show that fluid flow occurs at very small thermocapillary Reynolds number except for case of Rσ = −1. There are three types of two-dimensional steady flow depending on the capillary ratio, i.e., counter-clockwise unicellular flow, clockwise unicellular flow and flow pattern with two separate cells. When the Reynolds number exceeds the first critical thermocapillary Reynolds number, three-dimensional steady flow appears, while the three-dimensional or two-dimensional oscillatory flow takes place above the second critical point. The fluctuations of temperature and concentration on the free surface indicate that three-dimensional oscillatory thermal-solutal capillary flow appears as either the coexistence of “hydro-thermal wave” (HTW) and “hydro-solutal wave” (HSW), or the “vibrating straight spokes”. Both the first and second critical thermocapillary Reynolds numbers firstly decrease, and then increase slowly when the capillary ratio varies from 0 to −1. Moreover, it is found that the critical frequency and critical wave number for the flow pattern transitions are greatly dependent on the capillary ratio.

This paper presents a series of three-dimensional numerical simulations on the effect of surface heat dissipation on thermocapillary convection of moderate Prandtl number fluid in a shallow annular pool. The annular pool with a fixed aspect ratio of 0.05 and radius ratio of 0.5 is filled with 0.65 cSt silicone oil. Its Prandtl number is 6.7. Biot number of surface heat dissipation ranges from 0 to 50. The results show that when Marangoni number is small, thermocapillary convection is the axisymmetric steady flow. When Marangoni number exceeds the critical value, the basic flow will destabilize and transit to the hydrothermal waves that propagate along the clockwise or anticlockwise direction. The critical Marangoni number of the flow destabilization increases with the increase of Biot number. Furthermore, when Biot number increases, the radial temperature gradient on the free surface decreases near the inner cylindrical wall, but increases near the outer cylindrical wall, which results in the thermocapillary convective cell moving gradually from the inner to the outer cylindrical walls. After the flow destabilizes, the temperature fluctuation on the free surface mainly appears near the outer cylinder at a large Biot number.

In order to understand the effect of Marangoni convection on the evaporation rate and the flow pattern, we performed a series of three-dimensional numerical simulations on evaporation process of sessile water droplet by introducing a kinetic model. Substrate temperature and the ratio of vapor pressure varied from 299 K to 308 K and from 0.92 to 0.99, respectively. The variation range of contact angle θ was between 9.15° and 120°. Results show that the axisymmetric ring-shape temperature distribution on droplet free surface transforms into a serrated temperature distribution because of the enhancing Marangoni convection with the increase of substrate temperature. In addition, with the decrease of vapor pressure, the total evaporation rate on free surface will be increased and the Marangoni effect will be enhanced. The flow pattern is axisymmetric at 90o ≤ θ ≤ 120o when the substrate temperature is fixed. However, it shifts to a multi-cellular pattern with the decrease of contact angle as a result of the competition between Marangoni flow and the evaporation. Additionally, the total evaporation rate increases with the increase of contact angle when contact angle is above 60o, but when the contact angle is below 60o, the trend is reverted. The temperature distribution becomes distinct at a small contact angle.

In order to understand surface heat dissipation dependence of thermocapillary convection for moderate Prandtl number fluid in a deep annular pool, a series of three-dimensional numerical simulations have been carried out by using the finite volume method. The radius ratio and the aspect ratio of an annular pool are fixed at 0.5 and 1.0, respectively. The working fluid is 0.65cSt silicone oil with Prandtl number of 6.7. Surface heat dissipation Biot (Bi) number is varied from 0 to 50. Results indicate that with the increase of Biot number, the radial temperature gradient near the inner cylindrical wall decreases, and near the outer cylindrical wall it increases, so the flow is enhanced. When 0

In order to understand the aspect ratio and capillary ratio dependence of the coupled thermal-solutal capillary-buoyancy flow in an annular pool subjected to radial temperature and solute concentration gradients, a series of three-dimensional numerical simulations are conducted by applying the finite volume method. The annular pool was filled with the silicon-germanium melt with the silicon mass fraction of 1.99% (Pr = 6.37 × 10−3 and Le = 2197.8). Results show that axisymmetric stable flow always occurs in an annular pool when the thermal capillary Reynolds number is relatively small. The evolution of the flow pattern undergoes two and three stages with the increase of the aspect ratio and the capillary ratio, respectively. Besides the special case of Rσ = −1, the critical thermal Reynolds number at which the flow bifurcates into a three-dimensional flow rises with the increase of the capillary ratio and the decrease of the aspect ratio. Various three-dimensional flow patterns, including the lotus-like pattern, spoke pattern, hydrosolutal waves, ear-like pattern, growth-ring-like pattern and petal-like pattern, appear in the annular pool. The transitions and characteristic parameters of these flow patterns are strongly related to the capillary ratio, aspect ratio and thermal capillary Reynolds number.

The precise diagnosis of cancer remains a great challenge; therefore, it is our research interest to develop safe, tumor-specific reagents. In this study, we designed nanovesicles derived from erythrocyte membranes; the nanovesicles are capable of recognizing tumor cells for both circulating tumor cell (CTC) capture and tumor imaging. The tumor-targeting molecules folic acid (FA) and fluorescein Cy5 were modified on the nanovesicle surface. The developed nanovesicles exhibit excellent tumor targeting ability both in vitro and in vivo for CTC capture and in tumor imaging. Compared with traditional immunomagnetic beads, the proposed nanovesicles are capable of avoiding non-specific adsorption as a derivative of red blood cells. Combined with a non-invasive means of micromanipulation, the nanometer-sized vesicles show a high purity of CTC capture (over 90%). In vivo, the nanovesicles can also be employed for efficient tumor imaging without obvious toxicity and side effects. In brief, the nanovesicles prepared herein show potential clinical application for integrated diagnosis in vitro and in vivo.