Highly sensitive surface plasmon resonance sensor with surface modified MoSe2/ZnO composite film for non-enzymatic glucose detection.

The rapid and accurate assessment of glucose concentration has been demonstrated to play a significant role in human health, such as the diagnosis and treatment of diabetes, pharmaceutical research and quality monitoring in the food industry, necessitating further development of the performance for glucose sensor especially at low concentrations. However, glucose oxidase-based sensors suffer from crucial restriction in bioactivity because of their poor environmental tolerance. Recently, catalytic nanomaterials with enzyme-mimicking activity, known as nanozymes, have gained considerable interest to overcome the drawback. In this scenario, we report an inspiring surface plasmon resonance (SPR) sensor for non-enzymatic glucose detection employing ZnO nanoparticles and MoSe2 nanosheets composite (MoSe2/ZnO) as sensing film, featuring desirable advantages of high sensitivity and selectivity, lab-free and low cost. The ZnO was used to specifically recognize and bind glucose, and further signal amplification was realized by incorporating of MoSe2 owing to its larger specific surface area and favorable bio-compatibility, as well as high electron mobility. These unique features of MoSe2/ZnO composite film result in an obvious improvement of sensitivity for glucose detection. Experimental results show that the measurement sensitivity of the proposed sensor could reach 72.17 nm/(mg/mL) and a detection limit of 4.16 µg/mL by appropriately optimizing the componential constitutions of MoSe2/ZnO composite. In addition, the favorable selectivity, repeatability and stability are demonstrated as well. This facile and cost-effective work provides a novel strategy for constructing high-performance SPR sensor for glucose detection and a prospective application in biomedicine and human health monitoring.

Broadband coherent perfect absorption employing an inverse-designed metasurface via genetic algorithm.

Coherent perfect absorption (CPA) possesses the unique characteristics of flexibly and actively molding the flow of light. However, restricted by the low design efficiency and limited geometry variety of metamaterial structures, the common CPA metamaterial absorbers based on artificial design show poor performance in bandwidth operation. Here, we proposed a tungsten-based metamaterial absorber to achieve broadband CPA via employing genetic algorithm inverse design. Under the irradiation of two coherent beams, the high coherent absorption (>90%) can be achieved within a wide range from 1.32 to 3.28 µm. By simply adjusting the relative intensity or phase difference of the two coherent beams, the absorption intensity can be continuously modulated to realize the transition between coherent perfect absorption and coherent perfect transparency. Moreover, the coherent absorption maintains greater than 90% over a broad range of incident angles for both TM and TE polarizations. The scattering matrix theorem is applied to explain the physical mechanism of CPA, and the analytical results exhibit good consistency with the numerical calculations. Such a tungsten-based CPA metamaterial absorber with broadband tunability and exceptional angular stability is expected to be utilized in optical signal processing chips, all-optical modulators, and optical switchers.

microRNA-16-5p suppresses cell proliferation and angiogenesis in colorectal cancer by negatively regulating forkhead box K1 to block the PI3K/Akt/mTOR pathway.

MicroRNAs (miRNAs/miRs) have aroused increasing attention in colorectal cancer (CRC) therapy. This study is designed for a detailed analysis of the roles of miR-16-5p and forkhead box K1 (FOXK1) in cell angiogenesis and proliferation during CRC in addition to their underlying mechanisms. CRC tissues and colon cancer cell lines (SW620 and HCT8) were investigated. qRT-PCR and Western blot were utilized to evaluate miR-16-5p and FOXK1 expression. Following gain- and loss-of-function assays on miR-16-5p or FOXK1, the effects of miR-16-5p and FOXK1 were assessed on cell angiogenesis and proliferation in CRC cells. A dual-luciferase reporter assay was employed to evaluate the binding relationship of miR-16-5p and FOXK1. Western blot was used to determine the effects of miR-16-5p and FOXK1 on key molecules of the PI3K/Akt/mTOR pathway. Highly expressed FOXK1 and lowly expressed miR-16-5p were observed in CRC cells and tissues. miR-16-5p overexpression or FOXK1 knockdown reduced CRC cell proliferation and angiogenesis of human umbilical vein endothelial cells co-cultured with the supernatant of CRC cells, whereas miR-16-5p silencing or FOXK1 upregulation caused opposite trends. Additionally, miR-16-5p negatively modulated FOXK1 expression. The blockade of the PI3K/Akt/mTOR pathway was triggered by miR-16-5p overexpression or FOXK1 silencing. In conclusion, miR-16-5p hampers cell angiogenesis and proliferation during CRC by targeting FOXK1 to block the PI3K/Akt/mTOR pathway.

Dynamical manipulation of a dual-polarization plasmon-induced transparency employing an anisotropic graphene-black phosphorus heterostructure.

Dynamical tunable plasmon-induced transparency (PIT) possesses the unique characteristics of controlling light propagation states, which promises numerous potential applications in efficient optical signal processing chips and nonlinear optical devices. However, previously reported configurations are sensitive to polarization and can merely operate under specific single polarization. In this work we propose an anisotropic PIT metamaterial device based on a graphene-black phosphorus (G-BP) heterostructure to realize a dual-polarization tunable PIT effect. The destructive interference coupling between the bright mode and dark modes under the orthogonal polarization state pronounced anisotropic PIT phenomenon. The coupling strength of the PIT system can be modulated by dynamically manipulating the Fermi energy of the graphene via the external electric field voltage. Moreover, the three-level plasmonic system and the coupled oscillator model are employed to explain the underlying mechanism of the PIT effect, and the analytical results show good consistency with the numerical calculations. Compared to the single-polarization PIT devices, the proposed device offers additional degrees of freedom in realizing universal tunable functionalities, which could significantly promote the development of next-generation integrated optical processing chips, optical modulation and slow light devices.

Dynamically tunable coherent perfect absorption in topological insulators at oblique incidence.

The effective engineering of light absorption has been the focus of intensive research to realize the novel optoelectronic devices based on a topological insulator, a unique topologically protected surface Dirac-state quantum material with excellent prospects in electronics and photonics. Here, we theoretically proposed a versatile platform for manipulating the light-matter interaction employing the dynamically tunable coherent perfect absorption (CPA) in the topological insulator Bi1.5Sb0.5Te1.8Se1.2(BSTS). By simply varying the phase difference between two coherent counter-propagating beams, the BSTS-based CPA device can be continuously switched from the high transparency state to the strong absorption state, leading to the modulation of absorption ranging from 0.2% to 99.998%. Under the illumination of TE-polarized wave, the high absorption (>90%) can be implemented within a broad range from 0.47 to 1.51 µm through a proper incident angle alteration. In addition, the quasi-CPA wavelength can be flexibly selected by tuning the bulk thickness of BSTS film while maintaining high modulation depth of 104. Such BSTS-based CPA device with flexible tunability, wide absorption modulation range, and high modulation depth is expected to be utilized in a wide range of potential applications such as in next-generation coherent detectors, coherent modulators, all-optical switches, and signal processors.

Highly sensitive detection of Hg2+ employing SPR sensor modified with chitosan/poly (vinyl alcohol)/SnO2 film.

Water contamination by mercury ions (Hg2+) causes irreversible and serious effect on the ambient environment, ecological systems, and human health, necessitating further improvement of Hg2+ monitoring at low concentrations. Here, we proposed a novel surface plasmon resonance (SPR) sensor for Hg2+ detection with desirable advantages of high sensitivity, simple operation, label-free, and low cost, in which the chitosan/poly (vinyl alcohol)/SnO2 composite film was modified on sensing surface as the active layer for sensitivity enhancement. Benefiting from the relatively high refractive index of SnO2 nanoparticles, the evanescent field generated at the metal-solution interface can be significantly enhanced, which results in a 5 times improvement of sensitivity. Through appropriate optimization in the aspects of componential constitutions, the sensor exhibits excellent sensitivity of 25.713 nm/µg/L and ultra-low calculated detection limit of 6.61 ng/L(32.95 pM). Such detection limit is strikingly lower than the limitation (10 nM) in drinking water set by the US Environmental Protection Agency. In addition, the as-prepared sensor presents relatively high selectivity for Hg2+, attributing to plenty of binding sites for specific adsorption produced by functionalized chitosan/poly (vinyl alcohol) composites, which have been furtherly verified by characterization of FTIR and XPS spectra. The proposed sensor also exhibits great repeatability and good time stability for 15 days. This work provides a promising strategy for developing high-performance SPR sensor for Hg2+ detection and a prospective application in environmental monitoring.

Retrospective analysis of LNM risk factors and the effect of chemotherapy in early colorectal cancer: A Chinese multicenter study.

BACKGROUND: Estimating the risk of lymph node metastasis (LNM) is crucial for determining subsequent treatments following curative resection of early colorectal cancer (ECC). This multicenter study analyzed the risk factors of LNM and the effectiveness of postoperative chemotherapy in patients with ECC. METHODS: We retrospectively analyzed the data of 473 patients with ECC who underwent general surgery in five hospitals between January 2007 and October 2018. The correlations between LNM and sex, age, tumor size, tumor location, endoscopic morphology, pathology, depth of invasion and tumor budding (TB) were directly estimated based on postoperative pathological analysis. We also observed the overall survival (OS) and recurrence in ECC patients with and without LNM after matching according to baseline measures. RESULTS: In total, 473 ECC patients were observed, 288 patients were enrolled, and 17 patients had LNM (5.90%). The univariate analysis revealed that tumor size, pathology, and lymphovascular invasion were associated with LNM in ECC (P = 0.026, 0.000, and 0.000, respectively), and the multivariate logistic regression confirmed that tumor size, pathology, and lymphovascular invasion were risk factors for LNM (P = 0.021, 0.023, and 0.001, respectively). There were no significant differences in OS and recurrence between the ECC patients with and without LNM after matching based on baseline measures (P = 0.158 and 0.346, respectively), and no significant difference was observed between chemotherapy and no chemotherapy in ECC patients without LNM after surgery (P = 0.729 and 0.052). CONCLUSION: Tumor size, pathology, and lymphovascular invasion are risk factors for predicting LNM in ECC patients. Adjuvant chemotherapy could improve OS and recurrence in patients with LNM but not always in ECC patients without LNM.

Resolved Infrared Spectroscopy of Aqueous Molecules Employing Tunable Graphene Plasmons in an Otto Prism.

Real-time and in situ detection of aqueous solution is essential for bioanalysis and chemical reactions. However, it is extremely challenging for infrared microscopic measurement because of the large background of water absorption. Here, we proposed a wideband-tunable graphene plasmonic infrared biosensor to detect biomolecules in an aqueous environment, employing attenuated total reflection in an Otto prism configuration and tightly confined plasmons in graphene nanoribbons. Benefiting from the graphene plasmonic electric field enhancement, such a biosensor is able to identify the molecular chemical fingerprints without the interference of water absorption. As a proof of concept, the recombinant protein AG and goat anti-mouse immunoglobulin G (IgG) are used as the sensing analytes, of which the vibrational modes (1669 and 1532 cm-1) are very close to the OH-bending mode of water (1640 cm-1). Simulation results show that the fingerprints of protein molecules in the water environment can be selectively enhanced. Therefore, the water absorption is successfully suppressed so that two protein modes can be resolved by sweeping graphene Fermi energy in a wide waveband. By further optimizing the incident angle and graphene mobility to improve the mode energy of graphene plasmons, maximum enhancement factors of 112 and 130 can be achieved for amide I and II bands. Our work provides an effective approach for the highly sensitive and selective in situ identification of aqueous-phase molecular fingerprints in fields of healthcare, food safety, and biochemical sensing.

Elevated CA125 levels are associated with adverse clinical outcomes in acute pancreatitis: A propensity score-matched study.

OBJECTIVES: Glycosylation alterations are indicative of tissue inflammation and neoplasia. However, there are no large-sample, real-world studies assessing the levels of serum carbohydrate antigen 125 (CA125) in patients with acute pancreatitis (AP). We aimed to identify the association between elevated CA125 levels and adverse clinical outcomes in AP. METHODS: This was a retrospective cohort study with an analysis of 3939 patients with AP who were admitted to the First Affiliated Hospital of Nanchang University between January 2015 and September 2019 that used data from a prospectively maintained database. Multivariate logistic regression analysis and a propensity score-matched analysis were conducted to reveal the relationship between elevated CA125 levels and poor prognosis. RESULTS: The overall prevalence of elevated CA125 (>35 U/mL) levels was 38.51% (1517/3939) in AP patients. Elevated CA125 levels were independently associated with higher risks of mortality (adjusted odds ratio (AdjOR), 1.82; 95% confidence interval (CI), 1.30-2.54; P < 0.001), severe acute pancreatitis (SAP) (AdjOR, 2.40; 95% CI, 2.00-2.88; P < 0.001), and infected pancreatic necrosis (IPN) (AdjOR, 3.54; 95% CI, 2.65-4.71; P < 0.001). The propensity score-matched cohort analysis also demonstrated that mortality (OR, 1.57; 95% CI, 1.06-2.23; P < 0.05), SAP (OR, 2.20; 95% CI, 1.77-2.73; P < 0.001), and IPN (OR, 2.79; 95% CI, 1.98-3.92; P < 0.001) were more common in the elevated CA125 group than in the normal CA125 group. CONCLUSIONS: Elevated CA125 levels (>35 U/mL) are independently associated with adverse clinical outcomes in AP patients. These observations justify ongoing efforts to understand the role of CA125 in the pathogenesis and prognosis of AP.

Highly stable all-in-one photoelectrochemical electrodes based on carbon nanowalls.

Photoelectrochemical (PEC) cells offer a promising approach for developing low-cost solar energy conversion systems. However, the lack of stable and cost-effective electrodes remains a bottleneck that hampers their practical applications. Here, we propose a kind of integrated all-in-one three-dimensional (3D) carbon nanowall (CNW) electrode without sensitized semiconductors for stable all-carbon PEC cells. The all-in-one CNW electrodes were fabricated by directly growing CNW on both sides of the SiO2/Si/SiO2 wafer employing the radio frequency plasmon enhanced chemical vapor deposition method. Benefitting from the interconnected 3D textured structure, the CNW can effectively absorb the incident light and provide a large electrochemical reaction interface at the CNW surface that promotes the separation of photogenerated charge carriers, which makes it a superior electrode material. Experimental results show that the all-in-one CNW electrodes possess excellent PEC performance with a photocurrent density of 830 µA cm-2. Moreover, the CNW electrodes exhibit excellent photoresponses over a wide waveband and superior stability with a maintained photocurrent response, even after 60 d, which outperforms the electrodes using the other two-dimensional layered materials or semiconductor sensitized electrodes. Such an all-in-one electrode with impressive photovoltaic properties provides a promising platform for PEC applications that is eco-friendly with high efficiency, excellent stability and low cost.

New Risk Factors for Infected Pancreatic Necrosis Secondary to Severe Acute Pancreatitis: The Role of Initial Contrast-Enhanced Computed Tomography.

BACKGROUND AND AIMS: Pancreatic necrosis is a risk factor for poor prognosis of acute pancreatitis (AP). However, the associations between the findings on initial contrast-enhanced computed tomography (CT) of the pancreas and infected pancreatic necrosis (IPN) are unclear. METHODS: This was a retrospective cohort study. Patients with severe AP (SAP) from January 2014 to December 2016 at the First Affiliated Hospital of Nanchang University were enrolled and assigned to an IPN group and a non-IPN group. Univariate and multivariate logistic regression analyses were sequentially performed to assess the associations between the variables and IPN development. A receiver operating characteristic (ROC) curve was generated for the qualified independent risk factor. RESULTS: Forty-two patients with IPN were compared with 100 patients without IPN. Contrast-enhanced CT was performed 7 (range 3-10) days after AP onset. Multivariate stepwise logistic regression analyses showed that the number of acute peripancreatic fluid collections (APFCs) (OR 1.328, P = 0.006), presence of peripancreatic and pancreatic parenchymal necrosis (OR 4.001, P = 0.001), and gastrointestinal wall thickening (OR 3.353, P = 0.006) were independent risk factors for IPN secondary to SAP. The area under an ROC curve for the number of APFCs was 0.714, the sensitivity was 78.60%, and the specificity was 57.30% at a cutoff value of 4.5. CONCLUSIONS: The number of APFCs, presence of peripancreatic and pancreatic parenchymal necrosis, and gastrointestinal wall thickening were independent risk factors associated with IPN. As initial contrast-enhanced CT (about 7 days from AP onset) plays an important role in predicting IPN, it is important for clinicians to consider initial imaging of the pancreas.

Graphene-assisted multilayer structure employing hybrid surface plasmon and magnetic plasmon for surface-enhanced vibrational spectroscopy.

A graphene-assisted vertical multilayer structure is proposed for high performance surface-enhanced Raman scattering (SERS) and surface-enhanced infrared absorption (SEIRA) spectroscopies on a single substrate, employing simultaneous localized surface plasmon in the visible region and magnetic plasmon resonance in the mid-infrared region. Such multilayer structure consists of a monolayer graphene sandwiched between Ag nanoparticles (NPs) and a metal-insulator-metal (MIM) microstructure, which can be easily fabricated by a standard surface micromachining process. Benefiting from the large near field enhancement by the hybrid plasmons in both visible and mid-infrared regions, a high enhancement factor of up to 107 for SERS and 105 for SEIRA can be achieved. Additionally, the strong magnetic resonance of the MIM microstructure can be tuned in broadband to selectively enhance the desired vibration modes of molecules. The strong SERS and SEIRA enhancement together with easy fabrication provides new opportunities for developing integrated plasmonic devices for multispectral detection of molecules on the same substrate.

Strong coherent coupling between graphene surface plasmons and anisotropic black phosphorus localized surface plasmons.

The anisotropic plasmons properties of black phosphorus allow for realizing direction-dependent plasmonics devices. Here, we theoretically investigated the hybridization between graphene surface plasmons (GSP) and anisotropic black phosphorus localized surface plasmons (BPLSP) in the strong coupling regime. By dynamically adjusting the Fermi level of graphene, we show that the strong coherent GSP-BPLSP coupling can be achieved in both armchair and zigzag directions, which is attributed to the anisotropic black phosphorus with different in-plane effective electron masses along the two crystal axes. The strong coupling is quantitatively described by calculating the dispersion of the hybrid modes using a coupled oscillator model. Mode splitting energy of 26.5 meV and 19 meV are determined for the GSP-BPLSP hybridization along armchair and zigzag direction, respectively. We also find that the coupling strength can be strongly affected by the distance between graphene sheet and black phosphorus nanoribbons. Our work may provide the building blocks to construct future highly compact anisotropic plasmonics devices based on two-dimensional materials at infrared and terahertz frequencies.

Graphene-Based Long-Period Fiber Grating Surface Plasmon Resonance Sensor for High-Sensitivity Gas Sensing.

A graphene-based long-period fiber grating (LPFG) surface plasmon resonance (SPR) sensor is proposed. A monolayer of graphene is coated onto the Ag film surface of the LPFG SPR sensor, which increases the intensity of the evanescent field on the surface of the fiber and thereby enhances the interaction between the SPR wave and molecules. Such features significantly improve the sensitivity of the sensor. The experimental results demonstrate that the sensitivity of the graphene-based LPFG SPR sensor can reach 0.344 nm%-1 for methane, which is improved 2.96 and 1.31 times with respect to the traditional LPFG sensor and Ag-coated LPFG SPR sensor, respectively. Meanwhile, the graphene-based LPFG SPR sensor exhibits excellent response characteristics and repeatability. Such a SPR sensing scheme offers a promising platform to achieve high sensitivity for gas-sensing applications.

Social Capital and Quality of Life Among People Living With HIV/AIDS in Southeast China.

A cross-sectional study was conducted with 261 people living with HIV (PLWH) in Southeast China. A social capital questionnaire was used to measure social capital dimensions (trust, social connection, and social participation). A Chinese version of the Medical Outcomes Study HIV Health Survey (MOS-HIV) was used to assess Quality of Life (QoL); Physical Health Summary Scores (PHS) and Mental Health Summary Scores (MHS) were calculated. Multiple regression assessed whether social capital and its dimensions were associated with PHS and MHS. After controlling for sociodemographics and HIV-related factors, lower PHS scores were found among participants with low overall social capital (P < .01) and low trust (P < .001). Lower MHS scores were found among participants with low overall social capital (P < .001), low trust (P < .001) and low social connection (P < .01). Our findings identify potential intervention targets to improve QoL among PLWH in Southeast China, including the promotion of social capital.

The relationships among social support and quality of life in persons living with HIV/AIDS in Jiangxi and Zhejiang provinces, China.

Several empirical studies, particularly those conducted in developed countries, have linked social support to quality of life among persons living with HIV/AIDS (PLWA). However, few studies have been conducted in developing countries, such as China; therefore, the question of any association being present between social support and quality of life in PLWA in China remains unanswered. This retrospective cross-sectional study was conducted to examine the relationships between social support and quality of life among PLWA in the Jiangxi and Zhejiang provinces of China. A total of 377 PLWA participated in this study, and questionnaires used included demographics, the Chinese Medical Outcomes Study Short Form-36, and a Social Support Rating Scale, all of which were collected through face-to-face interviews between 1 March and 15 April 2013 in six different County Centers of Disease Control and Prevention in Jiangxi and Zhejiang provinces, and one hospital in the Jiangxi. The health-related quality of life score was 64.7±13.5 (out of a total score of 100), which was significantly lower than the national norm level of 78.2±15.9. The total score of social support was 29.4±7.8 (full score 66). The canonical correlation between social support and quality of participants' lives was shown to be statistically significant (p<0.0001). The relationship between subjective support and quality of life among PLWA was also significant (p=0.004). Subjective support and the use of social support showed a positive correlation with vitality, role-physical, and role-emotional, and a negative correlation with body pain. The current study suggests that PLWA with lower social support have diminished quality of life.

Insights from an observational assessment of park-based physical activity in Nanchang, China.

Internationally, parks have been shown to be an important community asset for physical activity (PA), but little is known about the relationship between park usage and physical activity in China. The purpose of this study was to determine the association between park user characteristics and PA in Nanchang, China. In June 2014, 75,678 people were observed in eight parks over 12 days using SOPARC, a validated systematic observation tool. A logistic regression analysis was used to determine the association between PA and park user characteristics. Most park users were older adults (53.5%) or adults (34.6%). Overall, 55% of park users engaged in moderate-to-vigorous physical activity (MVPA). Fewer women were observed in parks than men, but were 66% more likely to be engaged in MVPA than men. Park users were more likely to be observed in MVPA between 6-9 am and when the temperature was below 30 °C. Chinese park users were more active (55%) than US studies in Tampa (30%), Chicago (49%), and Los Angeles (34%). More research is necessary to identify features of parks that are associated with greater PA so that effective interventions can be developed to promote active park use in Chinese citizens.